CN104764687A - Portable water and soil conservation benefit evaluation device and evaluation method - Google Patents

Abstract

The invention provides a portable water and soil conservation benefit evaluation device based on a water and soil loss calculation equation. The device comprises a shell, a control unit in the shell and a remote data server, wherein the control unit uploads obtained data to the remote data server through a wireless network and comprises a data processing unit, a storage unit with a database, a wireless communication unit and a GPS navigation unit, wherein the storage unit, the wireless communication unit and the GPS navigation unit are respectively in communication connection with the data processing unit. According to the invention, the water and soil loss calculation equation is combined with the water and soil conservation benefit evaluation, the water and soil loss evaluation value of a piece of land is obtained by calculating the water and soil loss quantity of the land under different water and soil conservation measures, and the water and soil loss situation can be quantitatively evaluated in a scientific and normative manner; moreover, the water and soil conservation measures for the land can be evaluated under three conditions.

Description

A kind of portable water and soil conservation benefit evaluation device and evaluation method

Technical field

The present invention relates to soil erosion assessment monitoring field, be specifically related to a kind of portable water and soil conservation benefit evaluation device and evaluation method.

Background technology

Water and soil conservation is a fundamental state policy of China, is related to the sustainable development of national food security and economic society.The policy that since reform and opening-up, China adheres to for a long time " taking small watershed as unit, comprehensive planning, the comprehensive regulation " carries out water-and-soil conservation measures deployment, in water and soil conservation, achieve great achievement.

The concept of water-and-soil conservation measures is prevention soil and water loss, protection, improvement and Appropriate application water and soil resources, the general name of the improve the ecological environment technical measures such as taked engineering, plant and farming and control measures.Water-and-soil conservation measures is soil and water conservation benefit for the contribution weakened and prevent soil erosion, protection and improvement water and soil resources, the benign cycle of the promotion ecosystem and social economic system to develop in a healthy way.

In order to analyze water-and-soil conservation measures to the impact implementing region, find out its Problems existing in implementation process, and provide reference frame for next step water and soil conservation, need to carry out scientific and reasonable evaluation to water-and-soil conservation measures benefit, be referred to as soil and water conservation benefit evaluation.Soil and water conservation benefit evaluation is the computation and analysis to water-and-soil conservation measures contribution.

Problems existing in water-and-soil conservation measures implementation process can be found out by benefit evaluation, the cognition and comprehension water-and-soil conservation measures is to the Influencing Mechanism of soil erosion and region suitability thereof, repair the further control and plan scheme of volume for formulation and provide foundation, thus soil and water conservation benefit evaluation has great theory and practice meaning.

Nineteen ninety-five, Ministry of Water Resources has issued " Comprehensive Control of Soil Conservation Benefit Calculation " national standard, soil and water conservation benefit is divided into the large class of basic benefit, economic benefit, social benefit and ecological benefits 4, the specification computing method of soil and water conservation benefit.

Along with the raising of living standards of the people, eco-environmental evolvement strengthens gradually, Ministry of Water Resources revised in 2008 this edition GB, specify that basic benefit is water transfer efficiency of soil conservation, and added " improving slope drainage " and " adjustment small watershed runoff " two benefit contents; Highlight the importance of water resource and land resource.Although Kunming Market describes the computing method of all kinds of benefits of water-and-soil conservation measures in detail, before and after implementing concrete measure, the accurate computing method of the difference (soil conservation amount) of soil loss amount and front and back soil loss amount were not but introduced.

The computing method of water transfer soil conservation amount comparatively common in soil and water conservation benefit evaluation are at present water and soil conservation analytic approach and hydrological analysis method.Water and soil conservation analytic approach is called for short water and protects method, other water transfer soil conservation effect is divided by each water-and-soil conservation measures of actual observation, observe the Sediment soil erosion amount that mankind's activity is newly-increased during the Scour and Accretion collected in process and improvement simultaneously, thus calculate the water conservation soil conservation amount of water-and-soil conservation measures, and rough estimate water and soil conservation is to the sedimentation reduction effect in downstream.It intuitively can distinguish the effect of measures to change in water and sand, prediction water-sediment variation.But, not yet consider the impact of the measures such as crop material covering.Hydrological analysis method is called for short hydrology method, namely by run-off, the sedimentary loading observational data at statistical study hydrometric station, sets up hydrological statistics model, a kind of method of analyzed area water transfer soil conservation amount.Its principle is a basin, if underlying surface is constant, under certain condition of raining, will produce certain water yield and husky amount.Specifically there are computing method such as experience equation, different time series pairing comparision, double mass curve correlation method etc.The outstanding problem of hydrology method only reflects the effect of comprehensive water transfer soil conservation, and what be difficult to differentiation water-and-soil conservation measures retains benefit with other human activities to the impact of water sand.In addition, when basin in the given period exist simultaneously administer and destroy time, this method likely makes actual benefit of retaining less than normal.

In addition, after obtaining soil loss amount, need to evaluate the water-and-soil conservation measures in plot, to judge whether to proceed this kind of water-and-soil conservation measures, in addition, before building operation or planting are carried out to plot, also need to evaluate the soil and water conservation benefit in later stage, and existing evaluation method is all the mode taking directly to evaluate, evaluation method is not comprehensive and inaccurate, for the carrying out of soil and water conservation benefit evaluation causes difficulty.

In addition, do not distinguish forest land, meadow and shrub at traditional vegetal cover factor C and only calculate according to area coverage, this method truly can not reflect forest land, meadow and the shrub actual influence to water and soil conservation.Such as, in the situation of forest land, when forest exceedes certain altitude, but when earth's surface covers without grassland shrub, forest can not stop rainwater to the impact on earth's surface, soil and water conservation effect is far away from the situation of meadow and shrub under equal area coverage, but the C factor in the forest land situation obtained with traditional plant blanketing fctor acquisition methods but can be identical with the C factor in shrub situation with meadow under same homalographic.

Summary of the invention

The present invention is in order to solve the above-mentioned existing soil and water conservation benefit evaluation method Consideration mentioned comprehensively and the inaccurate shortcoming of result, in conjunction with Model of Soil Erosion, a kind of portable water and soil conservation benefit evaluation device based on soil erosion accounting equation is provided, the concrete quantity of real-time acquisition soil losses, and carry out soil and water conservation benefit evaluation.Model of Soil Erosion is applied to soil and water conservation benefit evaluation, not only there is unification, specification, quantitative and easy-operating feature, and also have good theory directive significance to real work.

Particularly, a kind of portable water and soil conservation benefit evaluation device, it comprises housing, is arranged on the control module of enclosure interior and remote data server, and control module carries out exchanges data by wireless network and remote data server;

The outside surface of described housing is provided with touch-screen, LCDs, FPDP and camera head, and described touch-screen, LCDs, FPDP, camera head are connected with control module communication respectively;

Described control module comprises data processing unit, storage unit, radio communication unit and the GPS navigation unit for navigating, and storage unit, radio communication unit and GPS navigation unit and described data processing unit respectively communication are connected;

Described storage unit is for storing the storehouse of rainfall product data for many years in rainfall region belonging to the topomap in plot and remote sensing images, plot, engineering measure factor data storehouse and tillage control measure factor data storehouse;

Described data processing unit comprises rainfall erosivity factor acquirement unit, soil erodibility factor acquiring unit, terrain factor acquiring unit, canopy density/cover degree acquiring unit, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit, tillage control measure factor acquirement unit and soil erosion assessment value computing unit;

Described rainfall erosivity factor acquirement unit is used for the storehouse of rainfall product data for many years according to rainfall region multiple in the plot of cell stores, calculates the rainfall erosivity factor R obtaining plot;

Soil erodibility factor acquiring unit, for gathering the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculates the extractable-P in soil obtaining plot;

Terrain factor acquiring unit calculates for the length of grade and the gradient gathering plot the slope length factor L and slope factor S that obtain each plot;

Described canopy density/cover degree acquiring unit obtains cover degree and canopy density according to cover degree photo and canopy density photo, and wherein said cover degree photo and canopy density photo can be obtained by described camera head;

Described vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit are respectively used to the vegetative coverage and biological control measure factor B, engineering measure factor E and the tillage control measure factor T that obtain plot;

Soil erosion assessment value computing unit is for calculating the soil loss amount A without the plot under water-and-soil conservation measures state or current virtual condition ₀and compare the soil loss amount A in plot under state ₁, and calculate the soil erosion benefit evaluation value P in plot, wherein

A ₀＝R*K*L*S*B ₀*E ₀*T ₀

A ₁＝R*K*L*S*B ₁*E ₁*T ₁

P＝(A ₁-A ₀)*100％/A ₀

Described touch-screen is for obtaining the touch operation of user;

Described LCDs is used for the soil erosion benefit evaluation value in display instrument duty and plot, the procedure for displaying of LCDs is achieved by the display unit communicated to connect with control module, owing to being well-known technology, the application repeats no more.

Preferably, without the value of vegetative coverage and biological control measure factor B under water-and-soil conservation measures state be 1, the value of engineering measure factor E is 1, the value of tillage control measure factor T is 1; Under current virtual condition or the vegetative coverage compared under state and biological control measure factor B undertaken by vegetative coverage and biological control measure factor acquirement unit that calculating obtains, engineering measure factor E is obtained from engineering measure factor data storehouse by engineering measure factor acquirement unit, tillage control measure factor T is obtained from tillage control measure factor data storehouse by tillage control measure factor acquirement unit.

Preferably, described LCDs is for showing multiple soil erosion benefit evaluation values in plot.

Preferably, vegetative coverage and biological control measure factor acquirement unit as described below for calculating the mode obtaining vegetative coverage and the biological control measure factor:

A1) if water-and-soil conservation measures be arable land, residential area, industrial and mineral land used, communications and transportation land used or waters land used time, then the value of vegetative coverage and biological control measure factor B is 1;

A2) if water-and-soil conservation measures belongs to field, forest land or meadow, and when the vegetation in vegetation plot to be restored only has vegetation cover degree, then the value of vegetative coverage and biological control measure factor B is calculated by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B i value of 24 periods, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\Σ}}}{B}_i\×R_i}{\underset{i=1}{\overset{24}{\mathrm{\Σ}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for annual rainfall erosivity;

A3) if water-and-soil conservation measures belongs to field, forest land or meadow, and vegetation has plant cover degree and canopy density simultaneously, then calculated the value of vegetative coverage and biological control measure factor B by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, and make vegetation overlay degree value by worthwhile for vegetation cover degree, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\Σ}}}{B}_i\×R_i}{\underset{i=1}{\overset{24}{\mathrm{\Σ}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for the annual agent of erosion.

Preferably, B _ivalue calculates in the following manner, and in formula, x represents plant cover degree value, and y represents B _ivalue:

A when soil-and-water conservation effect measure is meadow, as cover degree <40%, y=0.498e ^-0.03x; As cover degree >=40%, y=1.780e ^-0.03x;

B when soil-and-water conservation effect measure is shrub, as cover degree <40%, y=0.516e ^-0.04x; As cover degree >=40%, y=1.543e ^-0.06x;

C, when soil-and-water conservation effect measure is forest, calculates three B respectively according to cover degree and following formula c1, c2, c3 _ivalue, and to canopy density and B _ithe relation of value carries out linear fit, thus calculates the B under certain closing angle value _ivalue,

C1 when soil-and-water conservation effect measure is forest and the canopy density of forest are 25%, as cover degree <40%, y=0.424e ^-0.03x; As cover degree >=40%, y=1.511e ^-0.06x;

C2 when soil-and-water conservation effect measure is forest and the canopy density of forest are 50%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.395e ^-0.06x;

C3 when soil-and-water conservation effect measure is forest and the canopy density of forest are 75%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.283e ^-0.05x.

Preferably, a kind of soil erosion assessment method based on described soil erosion benefit evaluation device, it comprises the following steps:

S1, selected plan carry out the plot of soil erosion assessment;

S2, rainfall erosivity factor acquirement unit are according to the storehouse of rainfall product data for many years in rainfall region multiple in the plot of cell stores, calculate the rainfall erosivity factor R obtaining plot, soil erodibility factor acquiring unit gathers the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculate the extractable-P in soil obtaining plot, terrain factor acquiring unit gathers the length of grade in plot and the slope length factor L in each plot of gradient calculating acquisition and slope factor S;

S3, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit obtain vegetative coverage without plot under water-and-soil conservation measures state or under current virtual condition and biological control measure factor B respectively ₀, engineering measure factor E ₀and tillage control measure factor T ₀;

S4, soil erosion assessment value computing unit calculate the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀, wherein A ₀=R*K*L*S*B ₀* E ₀* T ₀;

S5, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit, according to vegetative coverage and biological control measure, engineering measure and the arable land measure of comparing plot under state, obtain the vegetative coverage and biological control measure factor B that compare plot under state respectively ₁, engineering measure factor E ₁and tillage control measure factor T ₁, the wherein said state that compares implements or eliminate the state of certain or some water-and-soil conservation measures;

S6, soil erosion assessment value computing unit calculate the soil loss amount A comparing plot under state ₁, wherein A ₁=R*K*L*S*B ₁* E ₁* T ₁;

S7, soil erosion assessment value computing unit are according to the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀with the soil loss amount A comparing plot under state ₁calculate the soil erosion benefit evaluation value P in plot, wherein P=(A ₁-A ₀) * 100%/A ₀.

Preferably, wherein without the value of vegetative coverage and biological control measure factor B under water-and-soil conservation measures state be 1, the value of engineering measure factor E is 1, the value of tillage control measure factor T is 1; Under current virtual condition or the vegetative coverage compared under state and biological control measure factor B undertaken by vegetative coverage and biological control measure factor acquirement unit that calculating obtains, engineering measure factor E is obtained from engineering measure factor data storehouse by engineering measure factor acquirement unit, tillage control measure factor T is obtained from tillage control measure factor data storehouse by tillage control measure factor acquirement unit.

Preferably, further comprising the steps of:

S8, compare state according to multiple, soil erosion assessment value computing unit calculates corresponding multiple soil erosion benefit evaluation value P in plot, in order to determine the water-and-soil conservation measures scheme that plot is suitable.

Preferably, to calculate the method obtaining vegetative coverage and the biological control measure factor as described below for vegetative coverage and biological control measure factor acquirement unit:

A1) if water-and-soil conservation measures be arable land, residential area, industrial and mineral land used, communications and transportation land used or waters land used time, then the value of vegetative coverage and biological control measure factor B is 1;

A2) if water-and-soil conservation measures belongs to field, forest land or meadow, and when the vegetation in vegetation plot to be restored only has vegetation cover degree, then the value of vegetative coverage and biological control measure factor B is calculated by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B i value of 24 periods, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for annual rainfall erosivity;

A3) if water-and-soil conservation measures belongs to field, forest land or meadow, and vegetation has plant cover degree and canopy density simultaneously, then calculated the value of vegetative coverage and biological control measure factor B by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, and make vegetation overlay degree value by worthwhile for vegetation cover degree, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for the annual agent of erosion.

Preferably, B _ivalue calculates in the following manner, and in formula, x represents plant cover degree value, and y represents B _ivalue:

A when soil-and-water conservation effect measure is meadow, as cover degree <40%, y=0.498e ^-0.03x; As cover degree >=40%, y=1.780e ^-0.03x;

B when soil-and-water conservation effect measure is shrub, as cover degree <40%, y=0.516e ^-0.04x; As cover degree >=40%, y=1.543e ^-0.06x;

C, when soil-and-water conservation effect measure is forest, calculates three B respectively according to cover degree and following formula c1, c2, c3 _ivalue, and to canopy density and B _ithe relation of value carries out linear fit, thus calculates the B under certain closing angle value _ivalue,

C1 when soil-and-water conservation effect measure is forest and the canopy density of forest are 25%, as cover degree <40%, y=0.424e ^-0.03x; As cover degree >=40%, y=1.511e ^-0.06x;

C2 when soil-and-water conservation effect measure is forest and the canopy density of forest are 50%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.395e ^-0.06x;

C3 when soil-and-water conservation effect measure is forest and the canopy density of forest are 75%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.283e ^-0.05x.

Advantage of the present invention is as described below:

One, soil erosion amount accounting equation combines with soil and water conservation benefit evaluation by the present invention, obtained the soil erosion assessment value in plot by the soil erosion amount under the different water and soil measures in calculating plot, quantitative evaluation can be carried out to soil erosion situation scientific and normally;

Two, benefit evaluation can be evaluated the water-and-soil conservation measures in plot under three circumstances according to actual conditions, and three kinds of situations comprise: the soil losses evaluation of existing water-and-soil conservation measures evaluation, water-and-soil conservation measures program evaluation and development construction item.(1) existing water-and-soil conservation measures evaluation refers to the benefit evaluation produced current existing water-and-soil conservation measures, this plot is original in water-and-soil conservation measures, intend implementing water-and-soil conservation measures to it, can suppose that implementing various these apparatus and method of water-and-soil conservation measures calculates soil erosion assessment value, according to the soil erosion assessment value calculated under different water-and-soil conservation measures state, obtain for the suitable water-and-soil conservation measures scheme in this plot; (2) water-and-soil conservation measures program evaluation refers to that carrying out water-and-soil conservation measures construction plan to the region of certain limit evaluates, implementer is helped to select optimum measure, originally there is water-and-soil conservation measures in this plot, intend transforming this plot, by these apparatus and method calculate remove existing water-and-soil conservation measures or change water-and-soil conservation measures after the soil erosion assessment value in plot, thus obtain for the suitable water-and-soil conservation measures modification scheme in this plot; (3) the soil losses evaluation of development construction item refers to and carries out comparative evaluation to two kinds of soil erosion situations under latter two situation before the exploitation disturbance of earth's surface, before intending constructing to this plot, constantly can carry out water and soil conservation value to it, electronics management can be served as;

Three, have employed unique vegetal cover and the preparation method of biological control measure factor B in the water and soil conservation loss evaluation method that the present invention proposes, the vegetal cover type of forest land, meadow and shrub can be distinguished, more truly reflect forest land, meadow and the shrub actual influence to water and soil conservation.

Four, the present invention is easy to carry, evaluates fast accurately, can serve as the role of electronics management, replace artificial management, reduce the subjectivity evaluated, the cost reducing engineering construction preparation in engineering.

Accompanying drawing explanation

Fig. 1 is the structural representation of water-and-soil conservation measures evaluating apparatus body of the present invention;

Fig. 2 is structural schematic block diagram of the present invention; And

Fig. 3 is the structural representation of data processing unit of the present invention.

Embodiment

Below in conjunction with specific embodiment and accompanying drawing, structure and working principle of the present invention is further explained:

First a basic inquiry unit can be selected when carrying out soil erosion survey, and Parcel division is carried out in basic inquiry unit, the continuous space scope with identical land use pattern, water-and-soil conservation measures type and canopy density/cover degree is divided into a plot.In the present invention, namely plot refers to the plot marked off in basic inquiry unit.

Rainfall region in the present invention refers to the continuum that rainfall amount that weather bureau announces is identical, and generally, the region in plot is less than the size in rainfall region.

As shown in Figures 1 and 2, the invention provides a kind of portable water and soil conservation benefit evaluation device, it comprises housing 1, is arranged on control module 2 and the remote data server 3 of housing 1 inside, control module 2 by wireless network by obtain data upload to remote data server 3 (not shown in figure 1).

Housing 1 comprises the camera head 100 being arranged on housing 1 outside and the FPDP being arranged on housing 1 outside, FPDP comprises the RJ45 network port 13, CAN data-interface 14, RS485 FPDP 15 and usb data port one 6, housing 1 is also provided with power light (not shown), touch-screen 11 and LCDs 12.

Touch-screen 11 can utilize touch operate, thus perform user instruction; The data communication with remaining soil and water conservation benefit evaluating apparatus or host computer can be realized by FPDP.

Control module 2 comprises data processing unit 21, storage unit 22, radio communication unit 23 and the GPS navigation unit 24 for navigating, and storage unit 22, radio communication unit 23 and GPS navigation unit 24 and data processing unit 21 respectively communication are connected.

Storage unit 22 is for storing the storehouse of rainfall product data for many years in rainfall region belonging to the topomap in plot and remote sensing images, plot, engineering measure factor data storehouse and tillage control measure factor data storehouse.

As shown in Figure 3, data processing unit 21 comprises rainfall erosivity factor acquirement unit 211, soil erodibility factor acquiring unit 212, terrain factor acquiring unit 213, canopy density/cover degree acquiring unit 214, vegetative coverage and biological control measure factor acquirement unit 215, engineering measure factor acquirement unit 216, tillage control measure factor acquirement unit 217 and soil erosion assessment value computing unit 218.

Rainfall erosivity factor acquirement unit 211, for the storehouse of rainfall product data for many years in multiple rainfall region in the plot that stores according to storage unit 22, calculates the rainfall erosivity factor R obtaining plot.

Soil erodibility factor acquiring unit 212, for gathering the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculates the extractable-P in soil obtaining plot.

Terrain factor acquiring unit 213 calculates for the length of grade and the gradient gathering plot the slope length factor L and slope factor S that obtain each plot.

Canopy density/cover degree acquiring unit 214 obtains cover degree and canopy density according to cover degree photo and canopy density photo, and wherein cover degree photo and canopy density photo can be obtained by camera head 100.

Vegetative coverage and biological control measure factor acquirement unit 215, engineering measure factor acquirement unit 216 and tillage control measure factor acquirement unit 217 are respectively used to the vegetative coverage and biological control measure factor B, engineering measure factor E and the tillage control measure factor T that obtain plot.

Soil erosion assessment value computing unit 218 is for calculating the soil loss amount A without the plot under water-and-soil conservation measures state or current virtual condition ₀and compare the soil loss amount A in plot under state ₁, and calculate the soil erosion benefit evaluation value P in plot, wherein

A ₀＝R*K*L*S*B ₀*E ₀*T ₀

A ₁＝R*K*L*S*B ₁*E ₁*T ₁

P＝(A ₁-A ₀)*100％/A ₀。

Below in conjunction with embodiment, the course of work of the present invention and principle are further explained:

Soil erodibility factor acquiring unit 212 obtains the extractable-P in soil in plot according to following formula:

$K=\{0.2+0.3\exp [-0.0256S_a(1-\frac{S_i}{100})\left]\right\}{\left(\frac{S_i}{C_l+S_i}\right)}^{0.3}[1-\frac{0.25C}{C+\exp (3.72-2.95C)}][1-\frac{0.7S_n}{S_n+\exp (-5.51+22.9S_n}]$

In formula: Sn=1-Sa/100; Sa is sand grain content % (2-0.05mm); Si is flour sand content % (0.05-0.002mm); Cl is clay content % (<0.002mm); C is organic carbon content (%).

Obtain the extractable-P in soil in plot and be stored in storage unit 22 inside.

Rainfall erosivity refers to that rainfall causes the potential ability of the soil erosion, reflects kinetic energy that raindrop have to the strike separating power of soil particle, and forms runoff to the transporting capacity of separated soil particle.

Particularly, rainfall erosivity factor acquirement unit 211 calculates first quarter moon rainfall erosivity long-time average annual value formula and is:

Rainfall erosivity refers to that rainfall causes the potential ability of the soil erosion, reflects kinetic energy that raindrop have to the strike separating power of soil particle, and forms runoff to the transporting capacity of separated soil particle.Rainfall erosivity R is the quantitative target representing rainfall erosivity, and concrete employing year rainfall erosivity long-time average annual value is demarcated.The computing formula of year rainfall erosivity long-time average annual value is:

In formula, for mean annual rainfall erosivity (MJmm/hm ²ha); K=1,2 ..., 24 is 1 year 24 first quarter moon.

k＝1，2，......，24

Wherein, for first quarter moon rainfall erosivity long-time average annual value, represent the rainfall erosivity (MJ (mm/hm of an annual control k first quarter moon ²(h), this value is by the formulae discovery of below:

α＝21.239β ^-7.3967

$\mathrm{\&beta;}=0.6243+\frac{27.346}{{\stackrel{\&OverBar;}{P}}_{d12}}$

${\stackrel{\&OverBar;}{P}}_{d12}=\frac{1}{n}\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{P}_{\mathrm{di}}$

In formula,

P _dijfor in statistical time range, 1 year kth first quarter moon jth day was more than or equal to the daily rainfall of 12mm; J=1,2 ..., m is the number of days that 1 year kth first quarter moon daily rainfall is more than or equal to 12mm; I=1,2 ..., N is the year number of statistical time range;

P _dito represent in statistical time range that I daily rainfall is more than or equal to the actual daily rainfall on the date of 12mm; L=1,2 ..., n is the number of days that in statistical time range, all daily rainfalls are more than or equal to 12mm;

represent that in statistical time range, daily rainfall is more than or equal to the daily rainfall mean value (mm) on the date of 12mm.

P in the above-mentioned formula of the acquisition of information of daily rainfall for many years in region, rainfall erosivity factor acquirement unit plot _dij,p _di, m, N and n value, thus calculate rainfall erosivity factor R.

Terrain factor acquiring unit 213 calculates slope length factor L and the slope factor S in each plot, and circular is as described below:

1, according to the different gradients, be several slope sections by each Parcel division, and measure length of grade and the gradient of each slope section;

2, according to segmentation slope formulae discovery slope length factor:

$L_i=\frac{{\mathrm{\&lambda;}}_i^{m+1}-{\mathrm{\&lambda;}}_{i-1}^{m+1}}{({\mathrm{\&lambda;}}_i-{\mathrm{\&lambda;}}_{i-1})*{\left(22.13\right)}^m}$

In formula: λ _iand λ _i-1be respectively the length of grade (m) of i-th and the i-th-1 slope section, m is length of grade index, becomes with gradient θ, notes working as λ _i=λ _i-1time, force slope length factor L _i=0;

3, slope factor is calculated according to gradient computing formula:

When land use pattern be woods, filling or careless type time, adopt the slope factor formulae discovery on gentle slope:

S＝10.8sinθ+0.03

When land use pattern is other type beyond woods, filling or grass, adopt the slope factor formulae discovery on segmentation slope:

In formula, S is slope factor, and θ is the gradient;

It is as described below that vegetative coverage and biological control measure factor acquirement unit calculate the method obtaining vegetative coverage and the biological control measure factor:

A1) if water-and-soil conservation measures be arable land, residential area, industrial and mineral land used, communications and transportation land used or waters land used time, then the value of vegetative coverage and biological control measure factor B is 1;

A2) if water-and-soil conservation measures belongs to field, forest land or meadow, and when the vegetation in vegetation plot to be restored only has vegetation cover degree, then the value of vegetative coverage and biological control measure factor B is calculated by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B i value of 24 periods, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for annual rainfall erosivity;

A3) if water-and-soil conservation measures belongs to field, forest land or meadow, and vegetation has plant cover degree and canopy density simultaneously, then calculated the value of vegetative coverage and biological control measure factor B by following method:

1. canopy density/cover degree database that storage unit 22 stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, and make vegetation overlay degree value by worthwhile for vegetation cover degree, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value in the rainfall product data storehouse stored in storage unit 22:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for the annual agent of erosion.

Further, B _ivalue calculates in the following manner, and in formula, x represents plant cover degree value, and y represents B _ivalue:

A when soil-and-water conservation effect measure is meadow, as cover degree <40%, y=0.498e ^-0.03x; As cover degree >=40%, y=1.780e ^-0.03x;

B when soil-and-water conservation effect measure is shrub, as cover degree <40%, y=0.516e ^-0.04x; As cover degree >=40%, y=1.543e ^-0.06x;

C, when soil-and-water conservation effect measure is forest, calculates three B respectively according to cover degree and following formula c1, c2, c3 _ivalue, and to canopy density and B _ithe relation of value carries out linear fit, thus calculates the B under certain closing angle value _ivalue:

C1 when soil-and-water conservation effect measure is forest and the canopy density of forest are 25%, as cover degree <40%, y=0.424e ^-0.03x; As cover degree >=40%, y=1.511e ^-0.06x;

C2 when soil-and-water conservation effect measure is forest and the canopy density of forest are 50%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.395e ^-0.06x;

C3 when soil-and-water conservation effect measure is forest and the canopy density of forest are 75%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.283e ^-0.05x.

The method that canopy density/cover degree acquiring unit 214 obtains closing angle value and cover degree value is as described below: camera head 100 is taken each plot, obtain canopy density photo and the cover degree photo in plot, canopy density/cover degree acquiring unit 214 obtains closing angle value and the cover degree value in each plot according to canopy density photo and cover degree photo.

Introducing below utilizes this soil erosion assessment device plot to be carried out to the method for soil erosion assessment, and it comprises the following steps:

S1, selected plan carry out the plot of soil erosion assessment;

S2, rainfall erosivity factor acquirement unit 211 are according to the storehouse of rainfall product data for many years in rainfall region multiple in the plot of cell stores, calculate the rainfall erosivity factor R obtaining plot, soil erodibility factor acquiring unit 212 gathers the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculate the extractable-P in soil obtaining plot, terrain factor acquiring unit 213 gathers the length of grade in plot and the slope length factor L in each plot of gradient calculating acquisition and slope factor S, and computing method are as described above.

S3, vegetative coverage and biological control measure factor acquirement unit 215, engineering measure factor acquirement unit 216 and tillage control measure factor acquirement unit 217 obtain vegetative coverage without plot under water-and-soil conservation measures state or under current virtual condition and biological control measure factor B respectively ₀, engineering measure factor E ₀and tillage control measure factor T ₀;

S4, soil erosion assessment value computing unit 218 calculate the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀, wherein A ₀=R*K*L*S*B ₀* E ₀* T ₀;

S5, vegetative coverage and biological control measure factor acquirement unit 215, engineering measure factor acquirement unit 216 and tillage control measure factor acquirement unit 217, according to vegetative coverage and biological control measure, engineering measure and the arable land measure of comparing plot under state, obtain the vegetative coverage and biological control measure factor B that compare plot under state respectively ₁, engineering measure factor E ₁and tillage control measure factor T ₁, the wherein said state that compares implements or eliminate the state of certain or some water-and-soil conservation measures;

S6, soil erosion assessment value computing unit 218 calculate the soil loss amount A comparing plot under state ₁, wherein A ₁=R*K*L*S*B ₁* E ₁* T ₁;

S7, soil erosion assessment value computing unit 218 are according to the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀with the soil loss amount A comparing plot under state ₁calculate the soil erosion benefit evaluation value P in plot, wherein P=(A ₁-A ₀) * 100%/A ₀.

Wherein without the value of vegetative coverage and biological control measure factor B under water-and-soil conservation measures state be 1, the value of engineering measure factor E is 1, the value of tillage control measure factor T is 1; Under current virtual condition or the vegetative coverage compared under state and biological control measure factor B carry out calculating by vegetative coverage and biological control measure factor acquirement unit and obtain, engineering measure factor E is obtained from engineering measure factor data storehouse by engineering measure factor acquirement unit, engineering measure database as shown in appendix 1, tillage control measure factor T is obtained from tillage control measure factor data storehouse by tillage control measure factor acquirement unit, and tillage control measure factor data storehouse is as shown in subordinate list 2.

S8, compare state according to multiple, soil erosion assessment value computing unit 218 calculates corresponding multiple soil erosion benefit evaluation value P in plot, in order to determine the water-and-soil conservation measures scheme that plot is suitable.

Last it is noted that above-described each embodiment is only for illustration of technical scheme of the present invention, be not intended to limit; Although with reference to previous embodiment to invention has been detailed description, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in previous embodiment, or to wherein partly or entirely technical characteristic carry out equivalent replacement; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.

Subordinate list 1 engineering measure factor graph layer data storehouse

Subordinate list 2 tillage control measure factor graph layer data storehouse

Continuous subordinate list 2

Continuous subordinate list 2

Continuous subordinate list 2

Continuous subordinate list 2

Continuous subordinate list 2

Continuous subordinate list 2

Claims (10)

1. a portable water and soil conservation benefit evaluation device, it comprises housing, is arranged on the control module of enclosure interior and remote data server, and control module carries out exchanges data by wireless network and remote data server;

The outside surface of described housing is provided with touch-screen, LCDs, FPDP and camera head, and described touch-screen, LCDs, FPDP, camera head are connected with control module communication respectively;

It is characterized in that:

Described control module comprises data processing unit, storage unit, radio communication unit and the GPS navigation unit for navigating, and storage unit, radio communication unit and GPS navigation unit and described data processing unit respectively communication are connected;

Described storage unit is for storing the storehouse of rainfall product data for many years in rainfall region belonging to the topomap in plot and remote sensing images, plot, engineering measure factor data storehouse and tillage control measure factor data storehouse; Described data processing unit comprises rainfall erosivity factor acquirement unit, soil erodibility factor acquiring unit, terrain factor acquiring unit, canopy density/cover degree acquiring unit, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit, tillage control measure factor acquirement unit and soil erosion assessment value computing unit;

Described rainfall erosivity factor acquirement unit is used for the storehouse of rainfall product data for many years according to rainfall region multiple in the plot of cell stores, calculates the rainfall erosivity factor R obtaining plot;

Soil erodibility factor acquiring unit, for gathering the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculates the extractable-P in soil obtaining plot;

Terrain factor acquiring unit calculates for the length of grade and the gradient gathering plot the slope length factor L and slope factor S that obtain each plot;

Described canopy density/cover degree acquiring unit obtains cover degree and canopy density according to cover degree photo and canopy density photo, and wherein said cover degree photo and canopy density photo can be obtained by described camera head;

Described vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit are respectively used to the vegetative coverage and biological control measure factor B, engineering measure factor E and the tillage control measure factor T that obtain plot;

Soil erosion assessment value computing unit is for calculating the soil loss amount A without the plot under water-and-soil conservation measures state or current virtual condition ₀and compare the soil loss amount A in plot under state ₁, and calculate the soil erosion benefit evaluation value P in plot, wherein

A ₀＝R*K*L*S*B ₀*E ₀*T ₀

A ₁＝R*K*L*S*B ₁*E ₁*T ₁

P＝(A ₁-A ₀)*100％/A ₀

Described touch-screen is for obtaining the touch operation of user;

Described LCDs is used for the soil erosion benefit evaluation value in display instrument duty and plot.

2. portable water and soil conservation benefit evaluation device according to claim 1, is characterized in that: without the value of vegetative coverage and biological control measure factor B under water-and-soil conservation measures state be 1, the value of engineering measure factor E is 1, the value of tillage control measure factor T is 1; Under current virtual condition or the vegetative coverage compared under state and biological control measure factor B undertaken by vegetative coverage and biological control measure factor acquirement unit that calculating obtains, engineering measure factor E is obtained from engineering measure factor data storehouse by engineering measure factor acquirement unit, tillage control measure factor T is obtained from tillage control measure factor data storehouse by tillage control measure factor acquirement unit.

3. portable water and soil conservation benefit evaluation device according to claim 1, is characterized in that: described LCDs is for showing multiple soil erosion benefit evaluation values in plot.

4. portable water and soil conservation benefit evaluation device according to claim 2, is characterized in that: vegetative coverage and biological control measure factor acquirement unit as described below for calculating the mode obtaining vegetative coverage and the biological control measure factor:

A1) if water-and-soil conservation measures be arable land, residential area, industrial and mineral land used, communications and transportation land used or waters land used time, then the value of vegetative coverage and biological control measure factor B is 1;

A2) if water-and-soil conservation measures belongs to field, forest land or meadow, and when the vegetation in vegetation plot to be restored only has vegetation cover degree, then the value of vegetative coverage and biological control measure factor B is calculated by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B i value of 24 periods, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for annual rainfall erosivity;

A3) if water-and-soil conservation measures belongs to field, forest land or meadow, and vegetation has plant cover degree and canopy density simultaneously, then calculated the value of vegetative coverage and biological control measure factor B by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, and make vegetation overlay degree value by worthwhile for vegetation cover degree, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 first quarter moon rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for the annual agent of erosion.

5. portable water and soil conservation benefit evaluation device according to claim 4, is characterized in that: B _ivalue calculates in the following manner, and in formula, x represents plant cover degree value, and y represents B _ivalue:

A when soil-and-water conservation effect measure is meadow, as cover degree <40%, y=0.498e ^-0.03x; As cover degree >=40%, y=1.780e ^-0.03x;

B when soil-and-water conservation effect measure is shrub, as cover degree <40%, y=0.516e ^-0.04x; As cover degree >=40%, y=1.543e ^-0.06x;

C, when soil-and-water conservation effect measure is forest, calculates three B respectively according to cover degree and following formula c1, c2, c3 _ivalue, and to canopy density and B _ithe relation of value carries out linear fit, thus calculates the B under certain closing angle value _ivalue:

C1 when soil-and-water conservation effect measure is forest and the canopy density of forest are 25%, as cover degree <40%, y=0.424e ^-0.03x; As cover degree >=40%, y=1.511e ^-0.06x;

C2 when soil-and-water conservation effect measure is forest and the canopy density of forest are 50%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.395e ^-0.06x;

C3 when soil-and-water conservation effect measure is forest and the canopy density of forest are 75%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.283e ^-0.05x.

6., based on a soil erosion assessment method for soil erosion benefit evaluation device according to claim 1, it is characterized in that: it comprises the following steps:

S1, selected plan carry out the plot of soil erosion assessment;

S2, rainfall erosivity factor acquirement unit are according to the storehouse of rainfall product data for many years in rainfall region multiple in the plot of cell stores, calculate the rainfall erosivity factor R obtaining plot, soil erodibility factor acquiring unit gathers the grains of sand content of plot soil, flour sand content, clay content and organic carbon content, calculate the extractable-P in soil obtaining plot, terrain factor acquiring unit gathers the length of grade in plot and the slope length factor L in each plot of gradient calculating acquisition and slope factor S;

S3, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit obtain vegetative coverage without plot under water-and-soil conservation measures state or under current virtual condition and biological control measure factor B respectively ₀, engineering measure factor E ₀and tillage control measure factor T ₀;

S4, soil erosion assessment value computing unit calculate the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀, wherein A ₀=R*K*L*S*B ₀* E ₀* T ₀;

S5, vegetative coverage and biological control measure factor acquirement unit, engineering measure factor acquirement unit and tillage control measure factor acquirement unit, according to vegetative coverage and biological control measure, engineering measure and the arable land measure of comparing plot under state, obtain the vegetative coverage and biological control measure factor B that compare plot under state respectively ₁, engineering measure factor E ₁and tillage control measure factor T ₁, the wherein said state that compares implements or eliminate the state of certain or some water-and-soil conservation measures;

S6, soil erosion assessment value computing unit calculate the soil loss amount A comparing plot under state ₁, wherein A ₁=R*K*L*S*B ₁* E ₁* T ₁;

S7, soil erosion assessment value computing unit are according to the soil loss amount A without plot under water-and-soil conservation measures state or current virtual condition ₀with the soil loss amount A comparing plot under state ₁calculate the soil erosion benefit evaluation value P in plot, wherein P=(A ₁-A ₀) * 100%/A ₀.

7. soil erosion assessment method according to claim 6, wherein without the value of vegetative coverage and biological control measure factor B under water-and-soil conservation measures state be 1, the value of engineering measure factor E is 1, the value of tillage control measure factor T is 1; Under current virtual condition or the vegetative coverage compared under state and biological control measure factor B undertaken by vegetative coverage and biological control measure factor acquirement unit that calculating obtains, engineering measure factor E is obtained from engineering measure factor data storehouse by engineering measure factor acquirement unit, tillage control measure factor T is obtained from tillage control measure factor data storehouse by tillage control measure factor acquirement unit.

8. soil erosion assessment method according to claim 6, further comprising the steps of:

S8, compare state according to multiple, soil erosion assessment value computing unit calculates corresponding multiple soil erosion benefit evaluation value P in plot, in order to determine the water-and-soil conservation measures scheme that plot is suitable.

9. the soil erosion assessment method according to any one of claim 7, is characterized in that: it is as described below that vegetative coverage and biological control measure factor acquirement unit calculate the method obtaining vegetative coverage and the biological control measure factor:

A1) if water-and-soil conservation measures be arable land, residential area, industrial and mineral land used, communications and transportation land used or waters land used time, then the value of vegetative coverage and biological control measure factor B is 1;

A2) if water-and-soil conservation measures belongs to field, forest land or meadow, and when the vegetation in vegetation plot to be restored only has vegetation cover degree, then the value of vegetative coverage and biological control measure factor B is calculated by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. in the rainfall product data storehouse of memory cell storage, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for annual rainfall erosivity;

A3) if water-and-soil conservation measures belongs to field, forest land or meadow, and vegetation has plant cover degree and canopy density simultaneously, then calculated the value of vegetative coverage and biological control measure factor B by following method:

1. canopy density/cover degree database that storage unit stores is called, the value of 24 vegetation cover degrees in vegetation plot to be restored is obtained from the vegetation overlay degree/cover degree database of 24 first quarter moons in vegetation plot to be restored, and make vegetation overlay degree value by worthwhile for vegetation cover degree, in conjunction with water-and-soil conservation measures, obtain vegetative coverage and the biological control measure factor B of 24 periods _ivalue, i=1,2 ... or 24;

2. in storage unit, 24 rainfall erosivity values and annual rainfall erosion force value in vegetation plot to be restored is obtained, the vegetative coverage final according to formulae discovery vegetation to be restored plot below and biological control measure factor B value:

$B=\frac{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{B}_i\&times;R_i}{\underset{i=1}{\overset{24}{\mathrm{\&Sigma;}}}{R}_i}$

In formula, B _ibe the biological control measure factor values of i-th first quarter moon, R _iit is the ratio that the rainfall erosivity of i-th first quarter moon accounts for the annual agent of erosion.

10. soil erosion assessment method according to claim 9, is characterized in that, B _ivalue calculates in the following manner, and in formula, x represents plant cover degree value, and y represents B _ivalue:

A when soil-and-water conservation effect measure is meadow, as cover degree <40%, y=0.498e ^-0.03x; As cover degree >=40%, y=1.780e ^-0.03x;

B when soil-and-water conservation effect measure is shrub, as cover degree <40%, y=0.516e ^-0.04x; As cover degree >=40%, y=1.543e ^-0.06x;

C, when soil-and-water conservation effect measure is forest, calculates three B respectively according to cover degree and following formula c1, c2, c3 _ivalue, and to canopy density and B _ithe relation of value carries out linear fit, thus calculates the B under certain closing angle value _ivalue,

C1 when soil-and-water conservation effect measure is forest and the canopy density of forest are 25%, as cover degree <40%, y=0.424e ^-0.03x; As cover degree >=40%, y=1.511e ^-0.06x;

C2 when soil-and-water conservation effect measure is forest and the canopy density of forest are 50%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.395e ^-0.06x;

C3 when soil-and-water conservation effect measure is forest and the canopy density of forest are 75%, as cover degree <40%, y=0.392e ^-0.03x; As cover degree >=40%, y=1.283e ^-0.05x.