CN107860703B

CN107860703B - Soil erosion characteristic analysis method based on outdoor rainfall simulation and indoor soil testing

Info

Publication number: CN107860703B
Application number: CN201711063519.4A
Authority: CN
Inventors: 王国强; 傅致远; 阿膺兰; 彭岩波; 刘廷玺; 李小磊
Original assignee: Beijing Normal University
Current assignee: Beijing Normal University
Priority date: 2017-11-02
Filing date: 2017-11-02
Publication date: 2019-04-16
Anticipated expiration: 2037-11-02
Also published as: CN107860703A

Abstract

The present invention provides a kind of soil erosion characteristic analysis method based on outdoor rainfall simulation and indoor soil testing, the described method includes: choosing the different soil of at least two quality carries out the experiment of the rainfall simulation under constant raininess, Soil Erosion under constant raininess is obtained；The rainfall simulation experiment that the different soil of at least two quality is changed under raininess is chosen, Soil Erosion under variation raininess is obtained；The different soil of at least two quality is chosen, adds the organic fertilizer of different gradients respectively, rainfall simulation experiment is carried out, obtains the Soil Erosion of different organic matter contents；In conjunction with the Soil Erosion of Soil Erosion and different organic matter contents under Soil Erosion, variation raininess under constant raininess, analysis obtains the soil erosion characteristic.This method is applied to the soil permeation parameter that building has more Physical Mechanism by artificial rainfall test, analysis mode condition of raining.Soil erosion information can quick and precisely be analyzed.

Description

Soil erosion characteristic analysis method based on outdoor rainfall simulation and indoor soil testing

Technical field

The present invention relates to soil erosion study technical fields, particularly relate to a kind of based on outdoor rainfall simulation and indoor soil The soil erosion characteristic analysis method of test.

Background technique

In recent years, soil is important one of the environmental element of epigeosphere, it is both the output source and ring of surrounding material The received vector of border substance plays a crucial role in ground surface environment evolutionary process.The soil erosion is that moderns are worked as in limitation The global environmental hazard of the class survival and development, seriously restricts world sustained economic development.Global soil erosion area About 16.43 × 106km2, the 10.95% of the land occupation table gross area.It is estimated that China because caused by the soil erosion economic loss it is annual At 10,000,000,000 yuan or more.Therefore, the soil erosion is prevented and treated, improves the ecological environment, realize man and nature coordination and resource-environment-society Sustainable economic development, it has also become the great environmental problem of whole world common concern.

The runoff of rainfall and its generation is the major impetus for causing the soil erosion, with the progress of rainfall, surface soil Water characteristic, rainwash situation etc. all constantly change, and slope soil erosion is then correspondingly with erosion dynamic and anti-erosion The variation of property feature and respond.

Summary of the invention

The technical problem to be solved in the present invention is to provide a kind of soil based on outdoor rainfall simulation and indoor soil testing Erosion performance analysis method can fast and accurately analyze soil erosion characteristic.

In order to solve the above technical problems, the embodiment of the present invention provides one kind based on outdoor rainfall simulation and indoor soil survey The soil erosion characteristic analysis method of examination, which comprises

It chooses the rainfall simulation that the different soil of at least two quality carries out under constant raininess to test, obtain under constant raininess Soil Erosion；

The rainfall simulation experiment that the different soil of at least two quality is changed under raininess is chosen, is obtained under variation raininess Soil Erosion；

The different soil of at least two quality is chosen, adds the organic fertilizer of different gradients respectively, carries out rainfall simulation experiment, Obtain the Soil Erosion of different organic matter contents；

In conjunction with the soil of Soil Erosion and different organic matter contents under Soil Erosion, variation raininess under constant raininess Earth erosional features, analysis obtain the soil erosion characteristic.

Preferably, Soil Erosion under the constant raininess, comprising: constant raininess Caused by Sloping Surfaces runoff production change feature, perseverance Determine the variation characteristic that raininess Caused by Sloping Surfaces produces yielding flow and total amount of erosion under husky variation characteristic and constant raininess.

Preferably, the different soil of at least two quality of choosing carries out the experiment of the rainfall simulation under constant raininess, obtains Soil Erosion under to constant raininess, comprising:

First raininess, the second raininess, first gradient and second gradient are set, by the different soil of at least two quality It is respectively placed under different raininess and the gradient and carries out test analysis；

The production flow velocity rate changing condition of the different soil of at least two quality under the conditions of different gradient under two kinds of raininess is obtained, The production flow velocity rate changing condition is the constant raininess Caused by Sloping Surfaces runoff production change feature；Obtain different gradient item under two kinds of raininess The production sand rate changing condition of the different soil of at least two kinds of quality under part, the husky rate changing condition of the production is the constant rain Strong Caused by Sloping Surfaces produces husky variation characteristic；Obtain total diameter of the different soil of at least two quality under the conditions of different gradient under two kinds of raininess Flow and total amount of erosion, the yielding flow and total amount of erosion are that the variation of yielding flow and total amount of erosion under constant raininess is special Sign.

Preferably, Soil Erosion under the variation raininess, comprising: runoff with rainfall dynamic change characterization, It is lower seep with the dynamic change characterization of rainfall, the soil erosion with rainfall dynamic change characterization.

Preferably, the different soil of at least two quality of choosing is changed the experiment of the rainfall simulation under raininess, obtains Soil Erosion under to variation raininess, comprising:

It, will using lasting variation raininess and the first variation raininess, the second variation raininess, first gradient and second gradient being arranged The different soil of at least two quality is respectively placed under the different gradient and variation raininess and carries out test analysis；

Obtain the runoff production change situation of the different soil of at least two quality under the conditions of different raininess, the runoff production change shape Condition is dynamic change characterization of the runoff with rainfall；Obtain the different soil of at least two quality under the conditions of different raininess Accumulation infiltration capacity change over time situation, it is the lower infiltration with rainfall that the accumulation infiltration capacity, which changes over time situation, Dynamic change characterization；Obtain the erosion amount and erosion intensity variation shape of the different soil of at least two quality under the conditions of different raininess Condition, the erosion amount and erosion intensity changing condition are dynamic change characterization of the soil erosion with rainfall.

Preferably, the runoff changes with time deeply for slope runoff with the dynamic change characterization of rainfall and obeys power Function rule, slope runoff coefficient change in logarithmic function；

Lower seep extends with the dynamic change characterization of rainfall for the accumulation infiltration capacity under different raininess at any time And gradually increase, and at rainfall infiltration initial stage, the accumulation infiltration capacity slope of curve is larger, and infiltration capacity rises comparatively fast, thereafter due to entering Infiltration rate reduce, accumulation infiltration capacity increase trend slow down when reach stablize infiltrate the stage when, accumulation infiltration capacity increase slowly, variation speed Rate reduces to minimum；

The soil erosion is when rainfall intensity increases with the dynamic change characterization of rainfall, and erosion amount is gone through with rainfall When passage be gradually increased, and erosion intensity is then to increase in rainfall early period with the increase of rainfall intensity, after rainfall duration Phase reduces with the increase of rainfall intensity.

Preferably, the Soil Erosion of the different organic matter contents, comprising: dynamic of the content of organic matter to run-off Variation characteristic, the content of organic matter are special to the dynamic change of lower milliosmolarity to the dynamic change characterization and organic content of silt streamflow Sign.

Preferably, described to choose the different soil of at least two quality, the organic fertilizer of different gradients is added respectively, is dropped Rain simulated experiment obtains the Soil Erosion of different organic matter contents, comprising:

The different soil of at least two quality includes low organic matter contents soils and high organic content soil；

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils produce rheology Change situation and high organic content soil runoff production change situation；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils streamflow change Situation and high organic content soil streamflow change situation；

It is the low organic matter contents soils runoff production change situation, high organic content soil runoff production change situation, low organic Matter content soil streamflow change situation and high organic content soil streamflow change situation are that the content of organic matter moves run-off State variation characteristic；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils runoff Changing condition and high organic content soil streamflow change situation, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as L-L, L-M, L-H, obtains the soil streamflow change situation of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as H-L, H-M, H-H, obtains the soil streamflow change situation of H-L, H-M, H-H respectively.

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils silt flow Vector changing condition and high organic content soil sediment loss amount changing condition；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils silt loss Measure changing condition and high organic content soil sediment loss amount changing condition；

The low organic matter contents soils sediment loss amount changing condition, the variation of high organic content soil sediment loss amount Situation, low organic matter contents soils sediment loss amount changing condition and high organic content soil sediment loss amount changing condition are Dynamic change characterization of the content of organic matter to silt streamflow；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils silt Number of dropouts changing condition and high organic content soil sediment loss amount changing condition, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as L-L, L-M, L-H, obtains the soil sediment loss amount changing condition of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as H-L, H-M, H-H, obtains the soil sediment loss amount changing condition of H-L, H-M, H-H respectively.

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, milliosmolarity under low organic matter contents soils Changing condition and high organic content soil bacterial diversity amount changing condition；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, the low content of organic matter handles lower milliosmolarity and becomes Change situation and high organic content handle lower milliosmolarity changing condition；

It is milliosmolarity changing condition under the low organic matter contents soils, high organic content soil bacterial diversity amount changing condition, low It is organic content to lower infiltration that the lower milliosmolarity changing condition of content of organic matter processing and high organic content, which handle lower milliosmolarity changing condition, The dynamic change characterization of amount；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, the processing of the low content of organic matter is lower to seep It measures changing condition and high organic content handles lower milliosmolarity changing condition, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as L-L, L-M, L-H, obtains milliosmolarity changing condition under the processing of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, It is expressed as H-L, H-M, H-H, obtains milliosmolarity changing condition under the processing of H-L, H-M, H-H respectively.

The advantageous effects of the above technical solutions of the present invention are as follows:

In above scheme, this method passes through artificial rainfall test, soil erosion process dynamic under analysis mode condition of raining Variation characteristic, the results showed that, slope runoff changes with time deeply obeys Bending influence, and slope runoff coefficient is in logarithmic function Variation, soil infiltration rate analysis results are applied to the soil permeation parameter that building has more Physical Mechanism.The result shows that In numerous soil properties for influencing soil erodibility factor, the soil texture and the pairs of soil erodibility of particle group are had a major impact.

Detailed description of the invention

Fig. 1 is the method flow diagram of the embodiment of the present invention；

Fig. 2 is the production flow velocity rate schematic diagram of the lower 2 kinds of soil of 60mm of embodiment of the present invention h-1 raininess；

Fig. 3 is the production flow velocity rate schematic diagram of the lower 2 kinds of soil of 120mm of embodiment of the present invention h-1 raininess；

Fig. 4 a is the production sand rate schematic diagram of the lower 2 kinds of soil of 60mm of embodiment of the present invention h-1 raininess；

Fig. 4 b is the production sand rate schematic diagram of the lower 2 kinds of soil of 120mm of embodiment of the present invention h-1 raininess；

Fig. 5 a, 5b are the yielding flow schematic diagram of the lower 2 kinds of soil of simulated rainfall of the embodiment of the present invention；

Fig. 6 a, 6b are the total amount of erosion schematic diagram of the lower 2 kinds of soil of simulated rainfall of the embodiment of the present invention；

Fig. 7 a to 7c is the comparison diagram of depth of runoff and lower milliosmolarity under difference of embodiment of the present invention raininess；

Fig. 8 changes over time diagram for run-off under the conditions of different gradient of the embodiment of the present invention and raininess and is intended to；

Fig. 9 changes over time diagram for run-off under the conditions of different gradient of the embodiment of the present invention and raininess and is intended to；

Figure 10 changes over time figure for accumulation infiltration capacity under the conditions of different gradient of the embodiment of the present invention and raininess

Figure 11 changes over time schematic diagram for infiltration rate under the conditions of different gradient of the embodiment of the present invention and raininess；

Figure 12 changes over time schematic diagram to corrode under the conditions of different gradient of the embodiment of the present invention and raininess；

Figure 13 changes over time schematic diagram for erosion intensity under the conditions of different gradient of the embodiment of the present invention and raininess；

Figure 14 is the dynamic change schematic diagram of L-CK of embodiment of the present invention raininess gradually major diameter flow rate；

Figure 15 is the dynamic change schematic diagram of L-CK of embodiment of the present invention raininess gradually path flow rate；

Figure 16 is the dynamic change schematic diagram of H-CK of embodiment of the present invention raininess gradually major diameter flow rate；

Figure 17 is the dynamic change schematic diagram of H-CK of embodiment of the present invention raininess gradually path flow rate；

Figure 18 is the dynamic change schematic diagram of L-L of embodiment of the present invention diameter flow rate；

Figure 19 is the dynamic change schematic diagram of L-H of embodiment of the present invention diameter flow rate；

Figure 20 is the dynamic change schematic diagram of H-L of embodiment of the present invention diameter flow rate；

Figure 21 is the dynamic change schematic diagram of H-M of embodiment of the present invention diameter flow rate；

Figure 22 is the dynamic change schematic diagram of H-H of embodiment of the present invention diameter flow rate；

Figure 23 is the dynamic change schematic diagram of sediment loss amount when raininess of the embodiment of the present invention is gradually big；

Figure 24 is the dynamic change schematic diagram of raininess of the embodiment of the present invention gradually hour sediment loss amount；

Figure 25 is the dynamic change schematic diagram of sediment loss amount when raininess of the embodiment of the present invention is gradually big；

Figure 26 is the dynamic schematic diagram of raininess of the embodiment of the present invention gradually hour sediment loss amount；

Figure 27 is the dynamic change schematic diagram of L-L of embodiment of the present invention sediment loss amount；

Figure 28 is the dynamic change schematic diagram of L-H of embodiment of the present invention sediment loss amount；

Figure 29 is the dynamic change schematic diagram of H-L of embodiment of the present invention sediment loss amount；

Figure 30 is the dynamic change schematic diagram of H-M of embodiment of the present invention sediment loss amount；

Figure 31 is the dynamic change schematic diagram of H-H of embodiment of the present invention sediment loss amount；

Figure 32 is the dynamic change schematic diagram of L-CK of embodiment of the present invention raininess gradually big milliosmolarity at present；

Figure 33 is the dynamic change schematic diagram of L-CK of embodiment of the present invention raininess gradually small milliosmolarity at present；

Figure 34 is the dynamic change schematic diagram of H-CK of embodiment of the present invention raininess gradually big milliosmolarity at present；

Specific embodiment

To keep the technical problem to be solved in the present invention, technical solution and advantage clearer, below in conjunction with attached drawing and tool Body embodiment is described in detail.

As shown in Figure 1, a kind of soil erosion based on outdoor rainfall simulation and indoor soil testing of the embodiment of the present invention Characteristic analysis method, which comprises

Step 101: choosing the different soil of at least two quality and carry out the experiment of the rainfall simulation under constant raininess, obtain perseverance Determine Soil Erosion under raininess；

Step 102: choosing the different soil of at least two quality and be changed the experiment of the rainfall simulation under raininess, become Change Soil Erosion under raininess；

Step 103: choosing the different soil of at least two quality, add the organic fertilizer of different gradients respectively, carry out rainfall Simulated experiment obtains the Soil Erosion of different organic matter contents；

Step 104: in conjunction with Soil Erosion and different organic matters under Soil Erosion, variation raininess under constant raininess The Soil Erosion of content, analysis obtain the soil erosion characteristic.

The soil erosion characteristic analysis method based on outdoor rainfall simulation and indoor soil testing of the embodiment of the present invention, leads to Artificial rainfall test is crossed, soil erosion process dynamic variation characteristic under analysis mode condition of raining, the results showed that, slope runoff is deep It changes with time and obeys Bending influence, slope runoff coefficient changes in logarithmic function, and soil infiltration rate analysis results are It is applied to the soil permeation parameter that building has more Physical Mechanism.On the basis of soil erosion test, calculates and obtain different soil The extractable-P in soil e of earth type, the results showed that, in numerous soil properties for influencing soil erodibility factor, soil matter Ground and the pairs of soil erodibility of particle group have a major impact.

Specifically, the soil that the present invention is different using 2 kinds of quality, respectively sandy soil and loam, are derived from Shandong Province Qingdao i.e. Black area sloping upland.

Rainfall simulation tests the experimental site progress in Qingdao Agricultural University.Experiment uses wooden artificial runoff plots, Length 2m, width 0.75m, height 0.5m, soil thickness about 40cm.Rain controller is artificial using TSJY-081 type Full-automatic portable Rainfall simulator, setting raininess are 60mm/h and 120mm/h, and the gradient is 10 degree, 20 degree.Rainfall erosion experiment starts preceding use The raininess of 20mm/h carries out 2h and moistens, and soil moisture content is made to reach field capacity level, guarantees one rainfall event close consistent Under the conditions of carry out.Soil is loaded according to field bulk density, and rainfall erosion experiment with the raininess of 20mm/h carries out 2-3h before starting It is wet, so that soil moisture content is reached field capacity level, guarantees that one rainfall event is being carried out close under uniform condition.Experimentation In, runoff is collected every 5min after Surface Runoff, after collection, water sample is numbered and is mixed, rainfall duration 40min.Rainfall After beginning, every 5 minutes collection water samples and silt sample.

The surface layer 0-20cm soil sample is collected from slope surface different location respectively according to upper, middle and lower slope after rainfall, measures soil Bulk density and water content.Take mixed pedotheque measurement pH, organic matter, cation exchange capacity (CEC) (CEC), total nitrogen, available nitrogen, speed Imitate the content of phosphorus and available potassium.The muddy water mixing sample of collection measures sediment content after taking 105 DEG C of a portion drying, Middle a part carries out mud, water separation, measures the total nitrogen, total phosphorus content and the calculating amount of outflowing with water of flush water；Full nitrogen in silt, The content of rapid available phosphorus and available potassium and calculate with silt number of dropouts.

The soil weight is measured using core cutter method, and soil particle diameter analysis uses pipette method, and the content of organic matter uses potassium bichromate Oxidizing process measurement, using glass electrode method (water: soil=2.5:1) is used, CEC is divided using ammonium ion displacement method for pH measurement Analysis.Total nitrogen in soil and silt sample is measured using Kjeldahl method, and available phosphorus uses vanadium molybdenum Huang determined by ultraviolet spectrophotometry.

Constant raininess Caused by Sloping Surfaces runoff production change feature

As Fig. 2, Fig. 3 give the production flow velocity rate variation of two kinds of soil under the conditions of different gradient under two kinds of raininess.No matter Under 60mmh-1 or 120mmh-1 raininess, with the increase of rain time, produces flow velocity rate and show as the trend gradually increased. Two kinds of soil are compared, and the production miscarriage of loam will be significantly higher than the stream of sandy soil.And raininess increases, gradient increase effectively increases slope surface Runoff yield.In 60mm h-1 raininess, sandy soil are lower in 10 degree of other processing of slopes production stream speed ratio, and in 120mm h-1 rain Under strong, this species diversity reduces, but loam produces stream on 20 degree of slopes and is then much higher than other processing.

The formation of slope runoff is rainfall and the interaction of underlying surface natural cause as a result, its forming process can be divided into drop Water process stores infiltration process and overland flow process three phases.From the point of view of entire rainfall, loam produces flow velocity rate and is starting rank Duan Tigao is very fast, and then (20 or 30min) is then gradually gentle, and then linearly increasing trend is all presented in the entire rainfall stage in sandy soil. This is closely related with soil permeability, and compared with loam, sandy soil quality is thicker, and seepage of water is good, lower in entire rainfall to seep More, therefore, the overland flow of generation is small, causes production stream to be lower than loam, may and be not up to infiltration saturation in the process in 40min Time is later, therefore producing stream is in be continuously increased trend.And loam bad hydraulic permeability, it is more to generate runoff, but since it is easy shorter Reach lower infiltration saturation in time, therefore can reach production stream stable state shape body.And due to sandy soil good penetrability, it produces and flows small and slow, Ke Neng Stablize in experimental period and not up to and produces the stream stage.

Constant raininess Caused by Sloping Surfaces produces husky variation characteristic

Fig. 4 a and Fig. 4 b are set forth and produce husky rate variation under 60mm h-1 raininess and 120mm h-1 raininess, and two kinds Soil shows respective feature.The Soil Erosion Rate of loam increases trend as straight line first occurs in incubation time increase, Then reaching a relatively steady state under 60mm h-1 raininess, stable state time of occurrence is 25min at 10 degree of slopes, 20 degree At 35 minutes when slope.In 120mm h-1 raininess, the time advance of stable state appearance.Compared with loam, the erosional features of sandy soil are then It varies considerably.Since sandy soil particle is coarse, it is not easy to migrate with water, and loam quality is soft, particle is small, Yi Yidong, causes to produce husky Rate is significantly less than loam, and changes within entire rainfall duration smaller.Compared with producing stream, although raininess increases, soil is invaded Erosion amount increases, but this diversity ratio production flow velocity rate is much smaller.

The variation characteristic of yielding flow and total amount of erosion under constant raininess

The variation of run-off is a complicated process, under conditions of rainfall intensity is certain, the size of flow path surface Mainly determined by Soil Slope infiltration character with rainfall is held.From the point of view of total runoff yield, the gradient and raininess increase, and runoff yield is aobvious It writes and improves.Two kinds of soil are compared, and the quality of loam is thinner, infiltrate poor, therefore are easy to cause rainwash, therefore it is significantly high to produce stream In sandy soil.

Such as Fig. 5 a, 5b, Fig. 6 a, 6b, total amount of erosion is dramatically increased with gradient increase, under two kinds of rainfall intensities, is all showed 20 degree of slopes are significantly higher than 10 degree of slopes out, and the gradient, which increases, generates the increase of water flow flow rate, and kinetic energy increases, and soil adhesion subtracts It is small, thus cause fiuvial denudation is vertical to increase.Loam is easily washed since quality is thin and soft, causes the erosion amount of loam remote Higher than sandy soil, and this species diversity shows more significant in 60mm h-1 raininess ratio 120mm h-1 raininess, this is because dropping in height Under raininess degree, current scour dramatically increases degrading for sandy soil.But under two kinds of rainfall intensities, potamic transport ability is to loam Influence difference is little, this is equally also closely related with loam property, and under 60mm h-1 raininess, potamic transport ability is had reached Higher degree causes the potentiality further increased to reduce.

Specifically, the present invention is different with organic matter height, using the different soil of 2 kinds of quality, No.1 soil is derived from Shandong Qingdao Agricultural University, province campus, No. two soil are derived from Jimo area sloping upland.

Raininess design is 5 years and 10 according to return period T according to Qingdao City's rainfall intensity formula using variation raininess is lasted Two rainfall scenes that year is calculated, last and are set as 40min, sample every 8 minutes, and Characteristics of Precipitation is as shown in Table 1:

Table 1

Wherein, the return period refers to that the rainfall observational data through a fixed length statisticallys analyze, equal to or more than certain storm intensity There is primary Mean Time Between Replacement in rainfall, and unit is usually indicated with year.

Rainfall simulation tests the experimental site progress in Qingdao Agricultural University.Experiment uses wooden artificial runoff plots, Length 2m, width 0.75m, height 0.5m, soil thickness about 40cm.Rain controller is artificial using TSJY-081 type Full-automatic portable Rainfall simulator, soil are loaded according to field bulk density, and rainfall erosion experiment with the raininess of 20mm/h carries out 2-3h before starting It is wet, so that soil moisture content is reached field capacity level, guarantees that one rainfall event is being carried out close under uniform condition.Rainfall starts Afterwards, every 8 minutes collection water samples and silt sample, and surface layer 0- is collected from slope surface different location respectively according to upward slope, descending Water sample after sampling, is numbered and is stood by 20cm soil sample, and soil sample number sealing saves, and measures the soil weight and aqueous later Amount.Take the content of mixed pedotheque total nitrogen, total phosphorus, organic matter.The muddy water mixing sample of collection, takes a portion Sediment content is measured after 105 DEG C of drying, a portion carries out mud, water separation, and the total nitrogen, total phosphorus, TOC for measuring flush water are (total Organic carbon) content and calculate the amount of outflowing with water.

Runoff with rainfall Dynamic variation

As Fig. 7 a to 7c gives the runoff production change feature of two kinds of soil under the conditions of different raininess.Slope runoff is deep at any time Variation obey Bending influence, slope runoff coefficient in logarithmic function variation.Two kinds of raininess are compared, under T=10 raininess The stream that miscarriage is higher than under T=5 raininess is produced, with the increase of rain time, depth of runoff shows as the trend gradually increased.? Rainfall initial stage, the slope runoff coefficient under the conditions of two kinds of raininess later, reach metastable state all by small increase.Runoff system Number is apparently higher than T=5 raininess condition under the conditions of T=10 raininess, the variation of runoff coefficient under T=10 raininess in 0.08~ Runoff coefficient under 0.62, T=5 raininess changes in 0.06~0.38.When runoff coefficient reaches stable under the conditions of different raininess Between have different, with the increase of raininess, stablize the moment shifts to an earlier date therewith, compared with T=5 raininess Caused by Sloping Surfaces runoff under T=10 raininess The relatively stable time of coefficient generally lags about 6-8min.

Relationship between characteristics of rainfall and depth of runoff is extremely complex.According to water balance formula: (in formula: SWt is most Whole soil moisture content (mm), SW0 are initial soil moisture content (mm), and t is the time, and Rday is precipitation (mm), and Qsurf is earth's surface Run-off (mm), Ea are evapotranspiration (mm), and wseep is the water (mm) for entering aeration zone by soil profile, and Qgw is to return stream It measures (mm)).In this trial, rainfall duration 40min, evapotranspiration is negligible, and enters aeration zone by soil profile Water and return flow and be also suitable for the water balanced calculation of large watershed long-time rainfall, therefore this test runoff is mainly accepted a surrender The influence of rain feature and soil penetrability, as shown in figure 4, the comparative analysis of depth of runoff and infiltration capacity is shown under different raininess, Under the conditions of same raininess, if the penetrating power of soil is strong, depth of runoff is with regard to small, conversely, depth of runoff becomes larger.

The variation that depth of runoff is influenced by the gradient is a complicated process, in the certain condition of rainfall intensity and soil types Under, the size of rainwash depth is mainly determined by Soil Slope infiltration character.It can be seen from Fig. 8 that influence ratio of the gradient to runoff More regular: depth of runoff is essentially identical with the general trend of slope change, i.e., increases with rainfall duration.Under the conditions of two kinds of gradients Depth of runoff is in rainfall early period and no significant difference, and with the passage of rainfall duration, the depth of runoff under 10 ° of gradients is gradually higher than 5 ° of slopes Depth of runoff under degree, and gap is increasing.Influence this is mainly due to the gradient to depth of runoff mainly passes through influence slope surface It is realized by raininess degree with infiltrating.In the case where projected area (S1) is certain, with the increase of the gradient (θ), slope surface is by rain Area (S2=S1/cos θ) becomes larger so that slope surface raindrop are thinning, while slope growth is also beneficial to moisture and permeates downwards.Slope After degree increases, component of the runoff gravity on the direction of slope increases to accelerate through flow velocity, makes to hit that splash raindrop downward along slope surface Come to it is farther, be all conducive to increase runoff.

Similar rule such as Fig. 9, i.e. rainfall no significant difference early period is also presented in runoff coefficient, with pushing away for rainfall duration It moving, the runoff coefficient under 10 ° of gradients is gradually higher than the runoff coefficient under 5 ° of gradients, and gap is increasing, in the rainfall later period, 5 ° Runoff coefficient under the gradient gradually tends towards stability, and the runoff coefficient under 10 ° of gradients is still increasing, but amplification reduces.

The lower dynamic change seeped with rainfall

Figure 10 is that the accumulation infiltration capacity under a kind of 2 kinds of rainfall intensities of soil and 2 kinds of gradients changes over time process.Different rain Accumulation infiltration capacity under by force extends at any time and gradually increases, and at rainfall infiltration initial stage, accumulate the infiltration capacity slope of curve compared with Greatly, infiltration capacity rises very fast, and thereafter since infiltration rate reduces, accumulation infiltration capacity, which increases trend and slows down, infiltrates the stage when reaching stabilization When, accumulation infiltration capacity increases slowly, and rate of change reduces to minimum.It is also more significant that infiltration capacity difference is accumulated under different raininess, ponding Before generation, accumulation infiltration capacity is equal to the rainfall in a period of time, therefore, accumulates infiltration capacity more in the bigger same time of raininess Greatly.After runoff generates, since rainfall is identical, with the increase of rainfall intensity, runoff yield be increased, and accumulation is infiltrated total amount and subtracted It is few.In Figure 10, the accumulation infiltration capacity under 2 kinds of rainfall intensities compares, when rainfall intensity is T=10, under 5 ° and 10 ° of gradients Accumulation infiltration capacity is respectively 65.54mm and 44.17mm, accounts for the 60.23% and 48.15% of rainfall respectively, and rainfall intensity is T When=5, the accumulation infiltration capacity under 5 ° and 10 ° of gradients is respectively 88.93mm and 56.25mm, accounts for the 81.72% of precipitation respectively With 61.31%.Main cause may be that rainfall intensity increases, and raindrop landing kinetic energy increases, so that surface crust situation is serious, water Body Vertical Infiltration is reduced, and precipitation is quickly converted to rainwash mostly, and soil infiltration amount is reduced.

Two kinds of gradients compare, and it is almost the same that soil accumulates infiltration capacity curve.It is T=5 in rainfall intensity when the gradient is 5 ° Under T=10, Soil accumulation infiltration capacity is respectively 88.93mm and 65.54mm, when the gradient is 10 °, rainfall intensity be T=5 and Under T=10, Soil accumulation infiltration capacity is respectively 56.25mm and 44.18mm.Under rainfall intensity same case, soil infiltration amount It is reduced with the increase of the gradient.This may be because moisture infiltrating in the soil is related with the pressure in slope surface, and in slope surface Pressure mainly be made of the gravity and atmospheric pressure of water, with the increase of the gradient, the pressure in slope surface is along vertical slope surface side To component be gradually reduced, and the component along line of slope is gradually increased, simultaneously because water body is moved along slope surface, enters moisture The chance of soil is reduced, and infiltration rate is caused to reduce, and producing stream lasts in advance.Secondly, into the moisture in soil aperture in gravity It is moved under the force action of capillary attaction.But equally there are two component, one vertical with soil surface, transports moisture downwards Dynamic, one parallel with soil surface, makes moisture transverse movement, and a part is saturated upper soll layer, blocks rain infiltration, some is then Go out to leak earth's surface along hole, form runoff, this is also a reason for causing vegetation restoration rate to reduce.

Figure 11 is that the infiltration rate under a kind of 2 kinds of rainfall intensities of soil and 2 kinds of gradients changes over time process.As seen from the figure, Under different raininess, in rainfall early period, soil infiltration rate is mainly related with rainfall intensity, due to soil initial infiltration capacity compared with By force, rainfall intensity is less than the practical infiltration capacity of soil at this time, and precipitation is substantially all to be infiltrated, and soil infiltration rate is approximately equal to rainfall Intensity.Show as that rainfall intensity is bigger, the initial stage infiltration rate of soil is higher, and the infiltration rate respectively handled compares, and the gradient is 5 °, drop In the case of raininess degree is T=5, soil initial stage infiltration rate highest, the gradient is 10 °, and rainfall intensity is to infiltrate at the rainfall initial stage of T=10 Rate is minimum；Soil infiltration rate extends with rain time and is gradually reduced, and is especially producing stream initial stage, and infiltration rate reduces quickly, but This trend continues at any time gradually to slow down, and finally tends towards stability in rainfall later period infiltration rate.And in the larger situation of rainfall intensity, soil Earth stable infiltration rate numerical value shows as the lesser processing of slightly less than raininess.The analysis of causes is as follows, and raindrop kinetic energy is with rainfall intensity Increase and increase, the formation of surface soil skinning is mainly influenced by raindrop kinetic energy, with rainfall intensity increase surface crust Development enhancing, causes soil infiltration rate to decline to a great extent, rainfall majority is converted into runoff；Furthermore as rainfall carries out, soil water-containing Rate increases as amount of infiltrating water increases, and soil moisture content increase will affect soil infiltration rate, studies have shown that infiltration rate can be with Soil moisture content increase and reduce, thus soil infiltration rate shows as the lasting progress with rainfall and gradually decreases trend.

Influence about the gradient to water infiltration ability, although being studied there are many scholar, due to Method used and experimental condition difference, it was therefore concluded that be also not quite similar.Most researchers think due to as the gradient increases, water Layer increases along the impulse force of line of slope, and vertical slope surface pressure reduces, so infiltration rate increases with the gradient and reduced；Also part grinds Study carefully and shows the gradient and infiltrate not related.For this purpose, influence of this research with regard to the gradient to water infiltration ability is inquired into. As seen from the figure, soil moisture infiltration rate plots changes.

The soil erosion with rainfall dynamic change

As seen from Figure 12, under certain slope and soil types, different rainfall intensities, there is one for the soil erosion Fixed difference.When rainfall intensity increases, erosion amount is gradually increased with the passage of rainfall duration, and erosion intensity is then in rainfall Early period increases with the increase of rainfall intensity, reduces in later period rainfall duration with the increase of rainfall intensity.Main cause is to work as When raininess constantly increases, rainfall rate is accelerated, and rainfall increases in identical rain time, gradually actually infiltrating more than soil Ability causes soil permeability ability to decline, and soil moisture content is gradually saturated, and more rainfalls become rainwash, so that runoff Erosion becomes larger；Rainfall intensity is bigger simultaneously, and raindrop kinetic energy and terminal velocity are bigger, bigger to the destruction of upper soll layer stability, It is exactly that the rainfall erosion as caused by raindrop is bigger, therefore soil erosion amount increases with the increase of raininess.

The gradient is to influence an important terrain factor of the erosion caused by sloping surfaces, and under the conditions of identical other, the gradient invades slope surface The size variation of erosion intensity also has great influence effect.It can be obtained by Fig. 1-13, under the conditions of different raininess, soil erosion intensity Increase with the increase of the gradient.First increase tendency is presented with the increase of the gradient in Slope Soil Erosion Intensity under the conditions of rainfall erosion Basic reason is, with the increase of the gradient, the runoff that rainfall generates residence time in slope surface shortens, and water flow loss becomes It is small.The chance for infiltrating soil also becomes smaller, and runoff flow velocity increases, erosiveness enhancing.Simultaneously with the increase of the gradient, soil Stability reduce, corrosion resistance weaken, the two combine, result in the gradient increase soil erosion intensity also increase accordingly, Therefore, erosion intensity shows as increase tendency with the increase of the gradient.

Specifically, the soil that the present invention is different using 2 kinds of quality, No.1 soil are derived from Qingdao Agricultural University, Shandong Province school Garden, No. two soil are derived from Jimo area sloping upland.Content of organic matter difference is larger, and content is small for L soil, is H mostly content Soil.

The gradient is set as 10 degree.

Organic matter: applying organic fertilizer makes two kinds of soil organism grade classifications: low < 2%；In=2%；High > 2%, two kinds Soil sample does the above same treatment respectively.

Raininess: according to rainfall scene, being divided into ten rainfalls, and one rainfall event, which is divided into three and lasts, is set as 40min, every 8 Minute samples, and is spaced 1 hour between every rainfall.Blank group undergoes the ascending and descending two kinds of rainfalls of raininess, other The raininess of soil experience is ascending.It is the setting of rainfall scene with table 2:

The setting of 2 rainfall scene of table

Rainfall simulation tests the experimental site progress in Qingdao Agricultural University.Experiment uses wooden artificial runoff plots, Length 2m, width 0.75m, height 0.5m, soil thickness about 25cm.Rain controller is artificial using TSJY-081 type Full-automatic portable Rainfall simulator after rainfall starts, every 8 minutes collection water samples and silt sample, and measures volume of water sample.After sampling, Water sample is numbered and stood, soil sample number sealing saves.Mixed pedotheque is taken to measure its total nitrogen, total phosphorus, organic matter Content.Total nitrogen, total phosphorus, TOC and the sediment content of water sample are measured after water sample is filtered.

As shown in Figure 14, Figure 15, give under the conditions of different raininess plus when organic fertilizer, the low soil of the content of organic matter Runoff production change feature.When raininess is gradually big, first stage raininess is 60mm/h, this stage flows without production.This is because rainfall initial stage is native Saturation has not yet been reached in earth moisture, and raininess is small so that earth's surface rainfall is initially used for soil infiltration, therefore Surface Runoff is smaller even It is flowed without producing；Second stage rainfall is carried out after stopping rainfall 1h, second stage raininess is adjusted to 90mm/h, before having figure can be seen that 16min starts to produce stream in 16min30s still in soil moisture unsaturated period, and the runoff rate in this stage is constantly incremented by, Finally reach 0.43mm/min.This is because moisture of soil profile content progressivelyes reach saturation as the time increases, exceed soil Ability is holded just to start to generate runoff.Phase III raininess is 120mm/h, is advanced by the time of generating runoff than on last stage 14min.Since the raininess in this stage is larger, so that the runoff rate in this stage is all larger than second stage at each sampling moment, 0.59mm/min is incremented to by incipient 0.08mm/min.Gradually hour, first stage raininess are 120mm/ to same soil raininess H, to raininess it is gradually big when situation it is similar, in preceding 30min without runoff generate, but runoff generate time it is gradually bigger than raininess when mention Before, this is because raininess is larger, the rate of lower infiltration is small, so that surface soil moisture reaches saturation and generates runoff.Second-order Duan Yuqiang is 90mm/h, is to stop the rain 1h stage, and slowly lower seep starts unexpected moisture close to after saturation to the moisture of upper soll layer It carries out, so runoff is just generated in rainfall 3min.The runoff rate of preceding 32min is increased continuously, and the runoff of 32-40min Rate maintains an equal level, this illustrates that soil moisture is fully saturated and infiltration rate also repays stable rate.Due to being spaced 1h, third rank It is seeped under soil moisture so that soil moisture is not exclusively saturated when section starts, so runoff is generated in 1min19s, preceding 16min's Runoff rate is continuously increased, but out of 16-40min this period of time, and runoff rate is maintained at 0.6mm/min or so, and variation is not Greatly.

The dynamic change of the soil runoff of high organic content

As shown in Figure 16, Figure 17, give under the conditions of different raininess plus when organic fertilizer, the high soil of the content of organic matter Runoff production change feature.For raininess gradually in big situation, first stage raininess does not produce stream when being 60mm/h, similar to the first soil.The Two-stage produces flow velocity rate and is continuously increased, and reaches 0.32mm/min when to 32min and tends towards stability.Phase III produce produce flow velocity rate compared with Greatly, the flow velocity rate at initial stage has reached 0.22mm/min, and 0.43mm/min is reached after 40min and is tended towards stability.

Raininess gradually under small rain fall, does not occur runoff under the raininess of 60,90mm/h, the of the phase III 11min just occurs.It is all ever-increasing in preceding 32min internal diameter flow velocity rate, but when to 40min, runoff rate is gradually small, by 0.44mm/min is reduced to 0.28mm/min.

Soil dynamics of runoff variation after adding organic fertilizer, the dynamic change of L-L, L-M, L-H soil runoff.

Into the content of organic matter lower soil, addition organic fertilizer is divided into soil organic matter content three basic, normal, high Grade is indicated with L-L, L-M, L-H respectively.Figure 16, Figure 17 are respectively the variation of L-L, L-H processing diameter flow rate, in this test Middle L-M group does not occur runoff in three phases.

As shown in figure 18, L-L processing does not occur runoff, the diameter flow rate of last 8min in the preceding 32min that raininess is 60mm/h For 0.13mm/min.When raininess is 90mm/h, runoff generation time is 3min22s, and runoff rate is constantly incremented by, and arrives Reach 0.49mm/min when 32min, the runoff rate of the last one 8min is slightly decreased, and reduces 0.03mm/min.Work as raininess When for 120mm/h, the 28s after rainfall starts just generates runoff, and in addition to the runoff rate and 90mm/h in last 8min It handles outside identical, the rainfall rate in other periods is all larger than the phase same time of other processing.

Figure 19 is the dynamic changing process that L-H handles runoff rate under different raininess.Compared with L-L, contributing time shifts to an earlier date Runoff rate when 6min52s, 32min just reaches 0.15mm/min, and the runoff rate of final stage is 0.38mm/min, is 3 times of the same period of L-L phase.When raininess is 90mm/h, contributing time 1min40s, runoff rate shows as first increasing and put down afterwards Steady and stable trend, finally reaches 0.54mm/min.When raininess increase is 120mm/h, runoff time of occurrence further shifts to an earlier date, Stream is produced in 59s.In this stage of 8-16min, runoff rate is significantly increased to 0.62mm/min, but since 16-32min, The trend that slowly reducing but occurs in runoff rate is reduced to 0.57mm/min, but final stage is significantly increased to 0.75mm/ again min。

The dynamic change of H-L, H-M, H-H soil runoff

Into the content of organic matter higher soil, addition organic fertilizer is divided into soil organic matter content three basic, normal, high Grade is indicated with H-L, H-M, H-H respectively.Figure 20 and Figure 21 is respectively the dynamic change of H-L, H-M, H-H processing diameter flow rate.

Figure 22 is the dynamic change of the diameter flow rate of H-L processing, and when raininess is 60mm/h, runoff is not generated.When raininess becomes When for 90mm/h, runoff is generated in 32min15s, the runoff rate of this period of 32-40min is 0.07mm/min.When raininess is When 120mm/h, runoff generation time is 3min22s, and the trend constantly increased is presented in runoff rate, finally increases to 0.33mm/min.Figure 21 is the dynamic change of the diameter flow rate of H-M processing, does not occur runoff under 60mm/h and 90mm/h raininess, In 120mm/h raininess, until runoff just occurs in 32min.32-40min stage internal diameter flow velocity rate is 0.31mm/min.Figure 22 is The dynamic change of the diameter flow rate of H-H processing, in 60mm/h processing, to generate runoff.It is produced in the 10min of 90mm/h processing Stream, and produce flow velocity rate and incremental trend is presented tends to be steady to runoff rate at the end of rainfall.When raininess is 120mm/h, When runoff rate is always more than 90mm/h raininess, and be also that incremental trend is presented, the rate in the 32-40min stage increases Add maximum, finally increases to 0.45mm/min.

The dynamic change of the soil sediment loss amount of the low content of organic matter

Figure 23, Figure 24 are respectively the lower initial soil of the content of organic matter in raininess gradually big and raininess gradually silt in small situation The dynamic change of number of dropouts.The loss of soil occurred in the 16-24min stage in 90mm/h raininess as seen from Figure 11, The sediment loss amount in this stage is 0.90gm-2min-1.Sediment loss amount highest when to 32min, reaches 1.50gm- 2·min-1.But it is remarkably decreased in the number of dropouts of the last stage to 0.81gm-2min-1.When raininess is 120mm/ When h, whole process has the loss of silt, and the number of dropouts in first three period all maintains the left side 0.65gm-2min-1 The right side is increased to 1.20gm-2min-1 in the number of dropouts in the 4th period, and is terminated with this level maintenance to rainfall.

Compared with raininess gradually big processing, gradually small processing sediment loss amount is reduced raininess, but the time that silt loss generates In advance.In 120mm/h raininess, the sediment loss amount in most latter two stage is smaller, in 0.1gm-2min-1 or so.Work as rain When strong spoiled 90mm/h, sediment loss amount is gradually increased, and the 0.19gm-2min-1 by increases to 1.06gm-2 min-1.When raininess is that 60mm/h is handled, the amplitude of variation of sediment loss amount is larger, present reduce again after existing increase it is increased become Gesture.Larger, respectively 0.43,0.70gm-2min-1 in third and the 5th stage number of dropouts.

The dynamic change of the soil sediment loss amount of high organic content

As shown in figure 25, when raininess gradually big processing, the loss of silt is not generated under the raininess of 60mm/h.When raininess becomes When for 90mm/h, produced in third period husky, sediment loss amount is more steady, all in 0.3gm-2min-1 or less.Work as raininess When increasing to 120mm/h, the trend being slowly increased is presented in sediment loss amount is increased to by the 0.27gm-2min-1 originated The sediment loss amount of the 0.5gm-2min-1 of fourth stage, last stage and fourth stage is essentially identical.

When raininess is gradually small, do not occur the loss of silt under the conditions of 120mm/h and 90mm/h raininess.Such as Figure 26 institute Show, second stage after raininess is reduced to 60mm/h starts the loss for silt occur, occurs by a relatively large margin in the 4th period Increase, but last stage sediment loss amount drops to 0.29gm-2min-1 by 0.42gm-2min-1.

Add the dynamic change of organic soil sediment loss amount.

The dynamic change of L-L, L-M, L-H soil silt loss.

Due to there is not runoff in L-M is handled, so being also the loss for silt occur.Figure 27,28 respectively represent L- L, L-H processing in sediment loss amount dynamic change.Silt loss in L-L processing under 60mm/h raininess appears in the last one In the stage, measuring smaller is 0.15gm-2min-1.90mm/h processing is the most processing of sediment loss amount.Reach in 16min Maximum value 1.60gm-2min-1, other several periods are all within the scope of 0.42-0.67gm-2min-1.120mm/h The maximum value of processing appears in 24min, is up to 0.60mm/h, the first two period number of dropouts is well few, respectively 0.8,1.0g m-2·min-1。

When raininess is 60mm/h, preceding three phases are husky without producing, but the sediment loss amount of the last stage is rapid for L-H processing Increase, increases to 1.01gm-2min-1 from the sediment loss amount 0.20gm-2min-1 of beginning.With 60mm/h raininess phase Seemingly, when raininess is 90mm/h, the sediment loss amount of first four period is all in 0.3gm-2min-1 or so, but last single order Section has reached 1.44gm-2min-1.It compares for the first two raininess, the sediment loss amount variation under 120mm/h raininess is not Significantly, more steadily.The dynamic change of dynamic change Figure 28 L-H sediment loss amount of Figure 27 L-L sediment loss amount

The dynamic change of H-L, H-M, H-H soil silt loss

As seen from Figure 29, the silt loss of H-L processing mainly appears under 120mm/h raininess, and presentation first increases to be subtracted afterwards Trend, maximum value 0.60gm-2min-1, the sediment loss amount in other periods is in 0.08-0.29gm-2min-1 In range.Compared with other processing, H-M handles sediment loss amount minimum, does not go out under the raininess of 60mm/h and 90mm/h Existing silt loss.Only just reach 0.11gm-2min-1 in the final stage of 120mm/h raininess.When H-H processing, raininess Not occur silt loss in the case of 60mm/h.It when raininess is 90mm/h, exactly two is continuously increased, increases in the 8-24min stage It is begun to decline again when to 0.79gm-2min-1.In the case of raininess is 120mm/h, 8-16min is to be in increased trend, But back three phases slowly decline.

The dynamic change of milliosmolarity under low organic soil

As shown in figure 32, it when L-CK raininess is gradually big, is seeped under not occurring under 60mm/h raininess.When that raininess is 90mm/h Two stages start to seep under occurring, and milliosmolarity difference is little under two, three stages, all in 0.02mm/min or so.Latter two rank The lower milliosmolarity of section increases, respectively 0.06,0.09mm/min.Raininess is that milliosmolarity is most at present by 120mm/h, and when 8min just reaches 0.07mm/min is continuously increased 0.24mm/min later.L-CK raininess does not also generate in the case of the 120mm/h raininess of hour gradually Lower infiltration, when raininess is 90mm/h, the lower milliosmolarity of preceding three phases be it is ever-increasing, there be by a small margin gradually small in latter two stage, Lower milliosmolarity when in addition to 8min, other periods are above the lower milliosmolarity that raininess is 60mm/h processing.When raininess is 60mm/h Lower milliosmolarity is basicly stable, is maintained within the scope of 0.06-0.09mm/min.

The dynamic change of milliosmolarity under high organic-matter soil

Figure 34 is milliosmolarity variation diagram under H-CK raininess gradually big processing, is seen by figure to find out under the 60mm/h raininess of starting not There is lower seep.When raininess becomes 90mm/h, start to seep under occurring.What lower milliosmolarity presentation was first dramatically increased and was slowly increased becomes Gesture.It is identical when the variation tendency of the lower milliosmolarity of 120mm/h raininess is with 90mm/h, but the rainy milliosmolarity in each stage compares 90mm.h Nearly 1 times of Qiang Shi great.H-CK raininess gradually in small processing, seeps under not occurring under the first two raininess, and when last time rainfall starts The lower lower milliosmolarity seeped in the 8-32min stage increases very fast, and when 32min reaches 0.42mm/min, at the end of 60mm/h raininess rainfall 0.29mm/min is dropped to again.

Add the dynamic change of the lower milliosmolarity of organic fertilizer soil

The dynamic change of the lower milliosmolarity of L-L, L-M, L-H processing

L-L processing is seeped under not occurring under 60mm/h raininess.L-L is handled under 90mm/h raininess, starts in fourth stage It now seeps, up to 0.02mm/min, is reduced to 0.01mm/min at the end of rainfall.When 120mm/h raininess, lower infiltration time of occurrence In advance, and maximum in 16-24min, maximum value gradually decreases after being 0.05mm/min, but all at present than 90mm/h raininess Milliosmolarity is more.

L-M processing is seeped in the case where the last stage of 60mm/h raininess occurs, and lower milliosmolarity is 0.07mm/min.90mm/h rain Qiang Shi, infiltration rate progressively increase to 0.25mm/min, finally tend to be steady.When 120mm/h raininess, the lower infiltration in first four stage Rate is all ever-increasing, but last stage is reduced to 0.12mm/min.

L-H processing is seeped under not occurring under 60mm/h raininess.Start under appearance in the four-stage that raininess is 90mm/h It seeps, infiltration rate now increases to after 0.031mm/min and starts to be decreased to 0.027mm/min.When 120mm/h raininess, lower infiltration rate Rate is obviously accelerated, and increased maximum in the 8-16min stage starts to tend to be steady, be maintained at after increasing to 0.035mm/min 0.04mm/min or so.

The dynamic change of the lower milliosmolarity of H-L, H-M, H-H processing

H-L processing is seeped under not generating under 60mm/h raininess, is seeped in the case where the fourth stage of 90mm/h starts to generate, but lower infiltration Rate is small, within the scope of 0.02-0.04.After raininess becomes 120mm/h, infiltration rate is dramatically increased, and preceding four stage increases width Higher, maximum value 0.207mm/min is spent, although there is small size decline in last stage, but infiltration rate is still higher than two, three ranks Section.

H-M processing is seeped under not generating under 60mm/h raininess.It is seeped in the case where the second stage of 90mm/h raininess occurs, 8- The 24min stage is in increased trend, increases to 0.21mm/min always, and infiltration rate held stationary is until rainfall knot later Beam.When raininess is 120mm/h, infiltration rate is continuous steady growth, and the infiltration rate at the end of rainfall is 0.21mm/min.

H-H processing is seeped under also not occurring when raininess is 60mm/h.It is seeped in the case where the phase III of 90mm/h raininess generates, and And phase III rate is up to 0.09mm/min.When raininess is 120mm/h, infiltration rate is always maintained at becoming of steadily increasing Gesture, the infiltration rate at the end of rainfall reach 0.13mm/min.

It is the preferred embodiment of the present invention in summary, it is noted that for those skilled in the art For, without departing from the principles of the present invention, several improvements and modifications can also be made, these improvements and modifications It should be regarded as protection scope of the present invention.

Claims

1. a kind of soil erosion characteristic analysis method based on outdoor rainfall simulation and indoor soil testing, which is characterized in that institute The method of stating includes:

It chooses the rainfall simulation that the different soil of at least two quality carries out under constant raininess to test, obtains soil under constant raininess Erosional features；

The rainfall simulation experiment that the different soil of at least two quality is changed under raininess is chosen, soil under variation raininess is obtained Erosional features；

The different soil of at least two quality is chosen, adds the organic fertilizer of different gradients respectively, rainfall simulation experiment is carried out, obtains The Soil Erosion of different organic matter contents；

It is invaded in conjunction with the soil of Soil Erosion and different organic matter contents under Soil Erosion, variation raininess under constant raininess Feature is lost, analysis obtains the soil erosion characteristic；

Wherein:

Soil Erosion under the constant raininess, comprising: constant raininess Caused by Sloping Surfaces runoff production change feature, constant raininess Caused by Sloping Surfaces Produce the variation characteristic of yielding flow and total amount of erosion under husky variation characteristic and constant raininess；

The different soil of at least two quality of choosing carries out the experiment of the rainfall simulation under constant raininess, obtains under constant raininess Soil Erosion, comprising:

First raininess, the second raininess, first gradient and second gradient are set, the different soil of at least two quality is distinguished It is placed under different raininess and the gradient and carries out test analysis；

The production flow velocity rate changing condition of the different soil of at least two quality under the conditions of different gradient under two kinds of raininess is obtained, it is described Production flow velocity rate changing condition is the constant raininess Caused by Sloping Surfaces runoff production change feature；It obtains under two kinds of raininess under the conditions of different gradient The production sand rate changing condition of the different soil of at least two quality, the husky rate changing condition of the production is under the constant raininess Sediment yield on slope variation characteristic；Obtain the yielding flow of the different soil of at least two quality under the conditions of different gradient under two kinds of raininess And total amount of erosion, the yielding flow and total amount of erosion are the variation characteristic of yielding flow and total amount of erosion under constant raininess；

Soil Erosion under the variation raininess, comprising: runoff with rainfall dynamic change characterization, it is lower infiltration with rainfall The dynamic change characterization of journey, the soil erosion with rainfall dynamic change characterization；

The different soil of at least two quality of choosing is changed the experiment of the rainfall simulation under raininess, obtains under variation raininess Soil Erosion, comprising:

It, will be described using lasting variation raininess and the first variation raininess, the second variation raininess, first gradient and second gradient being arranged The different soil of at least two quality is respectively placed under the different gradient and variation raininess and carries out test analysis；

The runoff production change situation of the different soil of at least two quality under the conditions of different raininess is obtained, the runoff production change situation is The runoff with rainfall dynamic change characterization；Obtain the tired of the different soil of at least two quality under the conditions of different raininess Product infiltration capacity changes over time situation, and it is the lower dynamic seeped with rainfall that the accumulation infiltration capacity, which changes over time situation, Variation characteristic；The erosion amount and erosion intensity changing condition of the different soil of at least two quality under the conditions of different raininess are obtained, The erosion amount and erosion intensity changing condition are dynamic change characterization of the soil erosion with rainfall；

The Soil Erosion of the different organic matter contents, comprising: the content of organic matter to the dynamic change characterization of run-off, have Machine matter content is to the dynamic change characterization of silt streamflow and organic content to the dynamic change characterization of lower milliosmolarity；

It is described to choose the different soil of at least two quality, the organic fertilizer of different gradients is added respectively, carries out rainfall simulation experiment, Obtain the Soil Erosion of different organic matter contents, comprising:

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils runoff production change shape Condition and high organic content soil runoff production change situation；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils streamflow change situation With high organic content soil streamflow change situation；

The low organic matter contents soils runoff production change situation, high organic content soil runoff production change situation, low organic matter contain It measures soil streamflow change situation and high organic content soil streamflow change situation is that the content of organic matter becomes the dynamic of run-off Change feature；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils streamflow change Situation and high organic content soil streamflow change situation, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as L-L, L-M, L-H, obtains the soil streamflow change situation of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as H-L, H-M, H-H, obtains the soil streamflow change situation of H-L, H-M, H-H respectively.

2. the soil erosion specificity analysis side according to claim 1 based on outdoor rainfall simulation and indoor soil testing Method, which is characterized in that the runoff changes with time deeply for slope runoff with the dynamic change characterization of rainfall and obeys power Function rule, slope runoff coefficient change in logarithmic function；

It is described it is lower seep with rainfall dynamic change characterization be different raininess under accumulation infiltration capacity extend at any time and by It is cumulative to add, and at rainfall infiltration initial stage, the accumulation infiltration capacity slope of curve is larger, and infiltration capacity rises comparatively fast, thereafter due to infiltration rate Reduce, accumulation infiltration capacity increase trend slow down when reach stablize infiltrate the stage when, accumulation infiltration capacity increase slowly, rate of change subtracts To minimum；

The soil erosion is when rainfall intensity increases with the dynamic change characterization of rainfall, and erosion amount is with rainfall duration Passage is gradually increased, and erosion intensity is then to increase in rainfall early period with the increase of rainfall intensity, later period rainfall duration with The increase of rainfall intensity and reduce.

3. the soil erosion specificity analysis side according to claim 1 based on outdoor rainfall simulation and indoor soil testing Method, which is characterized in that it is described to choose the different soil of at least two quality, the organic fertilizer of different gradients is added respectively, is dropped Rain simulated experiment obtains the Soil Erosion of different organic matter contents, comprising:

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils sediment loss amount Changing condition and high organic content soil sediment loss amount changing condition；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils silt loss quantitative change Change situation and high organic content soil sediment loss amount changing condition；

The low organic matter contents soils sediment loss amount changing condition, high organic content soil sediment loss amount change shape Condition, low organic matter contents soils sediment loss amount changing condition and high organic content soil sediment loss amount changing condition are to have Dynamic change characterization of the machine matter content to silt streamflow；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, low organic matter contents soils silt loss Measure changing condition and high organic content soil sediment loss amount changing condition, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as L-L, L-M, L-H, obtains the soil sediment loss amount changing condition of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as H-L, H-M, H-H, obtains the soil sediment loss amount changing condition of H-L, H-M, H-H respectively.

4. the soil erosion specificity analysis side according to claim 1 based on outdoor rainfall simulation and indoor soil testing Method, which is characterized in that it is described to choose the different soil of at least two quality, the organic fertilizer of different gradients is added respectively, is dropped Rain simulated experiment obtains the Soil Erosion of different organic matter contents, comprising:

In the case where being not added with organic fertilizer state, under the conditions of obtaining and analyzing different raininess, milliosmolarity changes under low organic matter contents soils Situation and high organic content soil bacterial diversity amount changing condition；

In the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, the low content of organic matter handles lower milliosmolarity and changes shape Condition and high organic content handle lower milliosmolarity changing condition；

It is milliosmolarity changing condition under the low organic matter contents soils, high organic content soil bacterial diversity amount changing condition, low organic It is organic content to lower milliosmolarity that the lower milliosmolarity changing condition of matter content processing and high organic content, which handle lower milliosmolarity changing condition, Dynamic change characterization；

It is described in the case where adding organic fertilizer state, under the conditions of obtaining and analyzing different raininess, the low content of organic matter handles lower milliosmolarity and becomes Change situation and high organic content handle lower milliosmolarity changing condition, comprising:

Organic fertilizer is added into low organic matter contents soils makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as L-L, L-M, L-H, obtains milliosmolarity changing condition under the processing of L-L, L-M, L-H respectively；

Organic fertilizer is added into high organic content soil makes soil organic matter content be divided into basic, normal, high three grades, respectively It is expressed as H-L, H-M, H-H, obtains milliosmolarity changing condition under the processing of H-L, H-M, H-H respectively.