CN115407049B - Method for measuring and calculating carbon sink potential of soil in water and soil conservation engineering measures - Google Patents

Abstract

The invention discloses a method for measuring and calculating carbon sink potential of soil in water and soil conservation engineering measures, which comprises the steps of dividing the water and soil conservation engineering measures into a point type and a surface type; for spot-type tooling Cheng Cuoshi: the sediment accumulation and carbon fixation amount of the spot type tool Cheng Cuoshi is finally calculated by measuring the maximum storage capacity, the layered sediment accumulation of the blocked sediment amount, calculating sediment accumulation potential of the part of the spot type engineering which is not full, and the like; for face-type tooling Cheng Cuoshi: the carbon fixation amount of the surface engineering measures is finally calculated by calculating parameters such as the service life of the engineering measures, the area of a control area of the surface engineering measures, the soil erosion modulus of the surface engineering measures, and the like. And finally, calculating the total carbon sequestration amount of the engineering measures in the area by combining the results of the point-type engineering measures and the surface-type engineering measures. The invention scientifically and comprehensively considers the category of water and soil conservation engineering measures and the loss of carbon in the sediment transportation process, and the measuring and calculating result is more true and accurate.

Description

A method for measuring soil carbon sink potential of soil and water conservation engineering measures

technical field

The invention belongs to the technical field of soil and water conservation carbon sinks, in particular to a method for measuring and calculating soil carbon sinks for water and soil conservation engineering measures.

Background technique

Soil and water conservation engineering measures can effectively reduce soil erosion, fix and increase soil organic carbon content, and are an important way for soil carbon sinks. Li Yong et al. (2003) selected typical hilly and gully areas of the Loess Plateau for research, and took 12 check dams in the Nianzhuanggou watershed located in the northeast of Baota District, Yan'an City, Shaanxi Province as the research object. The results showed that: 1957～2000 The 12 check dams in the watershed have stored a total of 1.73×105 t of organic carbon, and the carbon storage intensity in the watershed has increased by 0.13-5.03 t·hm ² ·a ^-1 , with an average of 1.28 t·hm ² ·a ^-1 . Fu Suhua et al. (2009) found that the multi-year average sediment reduction benefits of water and soil conservation engineering measures such as fish scale pits and horizontal strips exceeded 90%. At the same time, other studies found that the construction of sedimentation tanks and small reservoirs can strengthen sedimentation and burial, forming a mineralized environment that is difficult to mineralize. The deep soil carbon can realize carbon burial and increase soil carbon sink. The check dam is the backbone of the water and soil erosion ditch control project. The installation of the check dam can not only increase the organic carbon content of the soil, but also block the mud and silt, turning the barren ditch into a small artificial plain, increasing the area of cultivated land, and greatly improving the surface vegetation. productive forces. Yuan Limin et al. (2014) found that sand barriers can reduce wind erosion, combined with planting vegetation to increase soil organic matter content and play a role in carbon sequestration. Yue et al. (2016) calculated the carbon flux characteristics caused by soil erosion/siltation at the small watershed scale, and at the same time calculated the changes in soil organic matter and CO ² fluxes caused by erosion at the national scale.

At present, when calculating the impact of soil erosion on soil carbon, the effect of soil and water conservation engineering measures on soil carbon is not considered, and the research on engineering measures is generally based on the actual measurement of soil carbon changes and is a study of a single engineering measure, and none of the soil and water conservation engineering measures are classified. However, there is currently no calculation method for soil carbon sinks in soil and water conservation engineering measures.

Contents of the invention

In view of the existing demand for the calculation of carbon sinks of water and soil conservation engineering measures, the purpose of the present invention is to provide a universally applicable method for measuring and calculating soil carbon sink potentials for different water and soil conservation engineering measures.

The purpose of the present invention is achieved by the following technical solutions:

A method for calculating soil carbon sink potential of soil and water conservation engineering measures, comprising the following steps:

Step 1, classifying the adopted soil and water conservation engineering measures: divided into surface measures and point measures; the surface measures are engineering measures for controlling soil erosion on the surface scale; Measures for the interception and storage of sand;

Step 2, determine the _maximum storage capacity Q of the point-type engineering measures and the layered deposition amount of the deposited sediment amount, the sum of the layered deposition amount is the point-type engineering measure and the accumulated sediment amount _Q ;

Step 3: Calculating the sediment storage potential of the unsilted part of the point-type project: using the maximum storage capacity of the point-type project measures minus the amount of sediment stored by the point-type project measures, that is: Q _max - Q _already ;

Step 4, calculate the coefficient α of other corrosion reduction effects that can be exerted after the point-type project reaches the maximum storage capacity;

Step 5, measuring the organic carbon content of the silt layer in the point-type engineering sedimentation layer and the soil organic carbon content in the erosion area;

Step 6: Calculating the amount of sediment and carbon fixation in point-type engineering measures: use formulas (1) to (5) to calculate:

C _point = C _{point already} + C _{point not} (1)

_Point C = Q _Potential G _Erosion /1000 (4)

Q _Potential = ( _QMax - _QHave ) + _QMax α (5)

In the formula: _point C is the amount of sediment carbon sequestered by point-type engineering measures, and the unit is t; _point C is the amount of deposited sediment carbon-fixed carbon by point-type engineering measures, and the unit is t; _point C is the future of point-type engineering measures Carbon sequestration potential, unit is t; Q _i is deposition amount of sediment layer i, unit is t; G _i is organic carbon content of sediment layer i, unit is kg/t; Q _is point engineering measure The amount of sediment that _has been stored is in t; the Q _potential is the total potential of sediment storage in point- _type projects, and the unit is t; The maximum storage capacity of type engineering measures, the unit is t; α is the coefficient of other corrosion reduction effects that point type projects can play after reaching the maximum storage capacity, the value range is 0~1, no unit;

Step 7, calculating the use year Y of engineering measures (for example, the construction time of engineering measures is 1990, and the calculation year is 2022, then Y is equal to 2022-1990=32 years);

Step 8, measuring the surface soil organic carbon content G _in the internal area of the surface engineering measures;

Step 9, measure the _area A of the control area of the surface-type engineering measures (obtained by measuring on the spot or on the topographic map);

Step 10: Establish the runoff plots of the non-surface engineering measures and the surface engineering measures respectively and measure the total annual sediment production of the plots; divide the annual total sediment production of the runoff plots of the non-surface engineering measures by the area of the plot to obtain the non-surface engineering measures The soil erosion modulus X ₀ of the surface engineering measures; the annual total sediment production of runoff plots with surface engineering measures divided by the area of the plot, to obtain the soil erosion modulus X of surface engineering measures;

Step 11, measure the amount of sediment transported, and calculate the sediment transport ratio SDR;

Step 12: Calculating the amount of sediment carbon fixation retained by surface-type engineering measures, using formulas (6)-(8) for calculation:

C _plane = Q _plane G _plane Y/1000 (6)

Q _surface = A _surface (X ₀ -X) (7)

X=X ₀ E (8)

In the formula: _surface C is the amount of carbon sequestration and carbon sequestration of surface engineering measures, in t; _surface Q is the annual soil erosion and sand reduction/sedimentation amount in the area of surface engineering measures, and the unit is t/a; _surface G is surface The organic carbon content of the surface soil in the internal area of the engineering measure is in kg/t; Y is the service year of the engineering measure in a; the _surface A is the control area of the surface engineering measure in km ² ; X ₀ is the non-face type Soil erosion modulus of engineering measures, unit is t/(km ² ·a); X is soil erosion modulus of surface engineering measures, unit is t/(km ² ·a); E is engineering measure factor (take Value refer to "China Soil Erosion Equation (CSLE)");

Step 13, measuring the soil organic carbon content G in the _erosion area and the sediment organic carbon content G _deposition in the deposition area in the surface engineering measure control area;

Step 14, calculate the total carbon sequestration of engineering measures in the area:

When the sediment transport ratio is not considered, formula (9) is used for calculation:

C=C _surface +C _point (9)

When considering the sediment transport ratio, formulas (10) to (11) are used for calculation:

C＝C _plane SDR+C _point +C _plane (1-SDR)b (10)

b=1-G _deposition /G _{control invasion} (11)

In the formula: C is the amount of carbon sequestration in the region, and the unit is t; SDR is the sediment transport ratio in the control area of engineering measures; G _{control encroachment} is the soil organic carbon content in the eroded area of the control area of surface engineering measures, the unit is kg/t; G _{sedimentation} is the sediment organic carbon content in the deposition area, the unit is kg/t.

Further, in step 1, the surface measures include: terraced fields, horizontal steps, horizontal ditches, bamboo ditch, fish scale pits, large fruit tree pits, sand barriers for sand fixation, engineering road protection, and the point measures include: slope surface Small-scale storage and drainage projects, ditch head protection, Gufang, Yudiba.

Further, in step 2, for the layered deposition volume of the deposited sediment volume, 20 cm is selected as a layer, and the deposition volume of the i-th layer of sedimentation sediment is expressed as Q _i ,

Q _i ＝A _i ·h _i ·BD _i /1000

Among them: Q _i is the silting volume of the i-th layer of silt, in t; A _i is the bottom area of the i-th layer of silt, in square meters; h _i is the thickness of the i-th layer of silt, in t m; BD _i is the sediment bulk density of the i-th layer of sediment, in kg/m ³ .

Further, in step 4, α=1-(S _{is full} /S _{is not} ), wherein: S _{is full} is the point-type engineering measure outlet sediment yield _after the point-type engineering measure is silted up, and the unit is t/yr; Export sediment yield when building point-type engineering measures, the unit is t/yr; yr means year.

Further, in step 5, the specific operation is: collect the sediment samples of the entire alluvial layer in a point-type project, use an organic carbon analyzer to measure the organic carbon content G _i of the i-th layer of the alluvial sediment, and take 20cm as a layer; The soil organic carbon content in the area is based on the 5cm soil samples collected from the soil surface of the erosion area, and is measured by an organic carbon analyzer. The soil organic carbon content in the erosion area of point-type engineering measures is expressed as G _{control erosion} .

Further, in Step 8, the specific operation is: collect a 5 cm soil sample in the surface layer of the internal area of the surface-shaped engineering measures, and use an organic carbon analyzer to measure the soil organic carbon content G _{inside the surface} .

Further, in step 10, the specific operation of establishing runoff plots with surfaceless engineering measures and surfaced engineering measures and measuring the total annual sediment production in the plots is: removing engineering measures for runoff plots with surfaceless engineering measures and surfaced engineering measures The other parameters are the same, and the sediment storage equipment is placed under the community to collect the sediment in the runoff. After each rainfall, the sediment is collected and weighed to obtain the amount of each sediment production, and the annual sediment production amount The sum is the total annual sediment production.

Further, in step eleven, the specific operation of measuring the amount of sediment transport and calculating the sediment transport ratio SDR is as follows: set up checkpoint stations at the exit of the area, place sediment storage equipment, collect sediment in the runoff, and Afterwards, the sediment is collected and weighed to obtain the amount of sediment transported each time. The sum of each sediment transport amount in a year is the total annual sediment transport amount, and the ratio of the total sediment transport volume to the total sediment production is the sediment transport volume. than SDR.

Further, in step thirteen, the specific operation is: collect 5 cm soil samples in the soil surface layer of the erosion area in the erosion area of the surface engineering measure control area, and collect the sediment samples of the entire alluvial layer in the deposition area, and use organic carbon analysis respectively. Determination of the soil organic carbon content G in the erosion area _{to control erosion} and the sediment organic carbon content G _deposition in the sedimentation area.

The advantages and beneficial effects of the present invention are: the present invention proposes for the first time the project measures for surface and point water and soil conservation, and in consideration of the change of soil organic carbon in the process of soil erosion-transportation-siltation, according to different data situations, generally Applicable methods for calculating carbon sequestration of water and soil conservation engineering measures. The present invention provides a soil carbon sink potential calculation method for different soil and water conservation engineering measures, which is more scientific and comprehensive than other calculation methods in the prior art, considering the types of soil and water conservation engineering measures and the carbon loss of sediment during transport, and the result more acurrate.

Description of drawings

The present invention will be further described below in conjunction with drawings and embodiments.

Fig. 1 is a schematic flow chart of the method of the embodiment of the present invention;

Fig. 2 is a location diagram of 2 terraced fields and bayonet stations in Embodiment 1 of the present invention.

Detailed ways

Example 1

As shown in Figure 1, a method for measuring soil carbon sink potential of soil and water conservation engineering measures includes the following steps:

The first step is to classify the engineering measures of water and soil conservation. The engineering measures for surface-scale soil erosion control are divided into surface-type measures, and the measures for intercepting and storing eroded sediment are divided into point-type measures.

Table 1 Classification of water and soil conservation engineering measures

Engineering measures applicable to this patent Classification terraced fields face shape horizontal step face shape horizontal groove face shape Zhujiegou face shape fish scale pit face shape large fruit tree pit face shape Sand barrier face shape Engineering road protection face shape Small slope storage and drainage project point type ditch head protection point type Gufang point type check dam point type

Step 2, determine the _maximum storage capacity Q of the point-type engineering measures and the layered deposition amount of the deposited sediment amount, the sum of the layered deposition amount is the point-type engineering measure and the accumulated sediment amount _Q ;

For the layered deposition amount of the deposited sediment amount, 20cm is selected as a layer, and the deposition amount of the i layer of the deposited sediment is expressed as Q _i ,

Q _i ＝A _i ·h _i ·BD _i /1000

Among them: Q _i is the silting volume of the i-th layer of silt, in t; A _i is the bottom area of the i-th layer of silt, in square meters; h _i is the thickness of the i-th layer of silt, in t m; BD _i is the sediment bulk density of the i-th layer of sediment, in kg/m ³ .

Step 3: Calculating the sediment storage potential of the unsilted part of the point-type project: using the maximum storage capacity of the point-type project measures minus the amount of sediment stored by the point-type project measures, that _is : _Qmax - Qha.

Step 4: Calculate the coefficient α of other corrosion reduction effects that can be exerted by point-type engineering measures after reaching the maximum storage capacity, which is 1 minus the amount of sediment produced at the outlet of point-type engineering measures after the point-type engineering measures are silted and the outlet when no point-type engineering measures are built The ratio of sediment yield;

α=1-(S _full /S _unfinished ), where: S _full is the sediment yield at the outlet of the point-type engineering measures after the point-type engineering measures are silted, and the unit is t/yr; S _{is not} the outlet when no point-type engineering measures are built Sediment production, unit is t/yr.

Step 5: Determining the organic carbon content of sediment layers in point-type projects and soil organic carbon content in erosion areas: collect sediment samples from the entire sediment layer in point-type projects, and use an organic carbon analyzer to measure the organic carbon content of the i-th layer of sediment layers. For the carbon content G _i , 20 cm is taken as a layer; the soil organic carbon content in the erosion area is based on the 5 cm soil samples collected from the soil surface in the erosion area, and the organic carbon analyzer is used to measure the soil organic carbon content G _erosion in the erosion area of point-type engineering measures.

Step 6, according to the formula (1)-(5), calculate the amount of sediment and carbon fixation in point-type engineering measures;

C _point = C _{point already} + C _{point not} (1)

_Point C = Q _Potential G _Erosion /1000 (4)

Q _Potential = ( _QMax - _QHave ) + _QMax α (5)

In the formula: _point C is the amount of sediment carbon sequestered by point-type engineering measures, and the unit is t; _point C is the amount of deposited sediment carbon-fixed carbon by point-type engineering measures, and the unit is t; _point C is the future of point-type engineering measures Carbon sequestration potential, unit is t; Q _i is deposition amount of sediment layer i, unit is t; G _i is organic carbon content of sediment layer i, unit is kg/t; Q _is point engineering measure The amount of sediment that has been stored is in t; the Q _potential is the total sediment storage potential of the point-type project, and the unit is t; G _erosion is the soil organic carbon content in the eroded area of the point-type project measure, and the unit is kg/t; _{the maximum} Q is The maximum storage capacity of point-type engineering measures, the unit is t; α is the coefficient of other corrosion reduction effects that point-type projects can play after reaching the maximum storage capacity, and the value ranges from 0 to 1, with no unit.

Step 7, calculate the use year Y of the engineering measures, for example, the construction time of the engineering measures is 1990, and the calculation year is 2022, then Y is equal to 2022-1990=32 years;

Step 8, measure the surface soil organic carbon content G _in the inner area of the surface-shaped engineering measures; the specific operation is: collect 5 cm soil samples in the surface layer of the inner area of the surface-shaped engineering measures, and use an organic carbon analyzer to measure the soil organic carbon content G _{in the surface} .

Step 9: Measure the _area A of the control area of the surface-type engineering measures (obtained by on-site or topographical map measurement).

Step 10: Establish the runoff plots of the non-surface engineering measures and the surface engineering measures respectively and measure the total annual sediment production of the plots; divide the annual total sediment production of the runoff plots of the non-surface engineering measures by the area of the plot to obtain the non-surface engineering measures The soil erosion modulus X ₀ of the surface engineering measure; the annual total sediment production of the runoff area of the surface engineering measure is divided by the area of the plot, and the soil erosion modulus X of the surface engineering measure is obtained; the establishment of the non-surface engineering measure and the surface engineering measure The specific operation of the runoff plot and the determination of the total annual sediment production in the plot is as follows: the runoff plots with no surface engineering measures and the runoff plots with surface engineering measures have the same parameters except engineering measures, and sediment collection equipment is placed under the plots to collect the sediment in the runoff. For sediment, the sediment is collected and weighed after each rainfall to obtain the amount of each sediment production, and the sum of each sediment production in a year is the total annual sediment production.

Step 11: Measure the amount of sediment transported and calculate the sediment transport ratio SDR. The specific operations are as follows: set up a bayonet station at the exit of the area, place sediment storage equipment, collect the sediment in the runoff, and remove the sediment after each rainfall. Collecting and weighing are carried out to obtain the amount of sediment transported each time. The sum of each sediment transport amount in a year is the total annual sediment transport amount, and the ratio of the total sediment transport amount to the total sediment production is the sediment transport ratio SDR.

Step 12: Calculating the amount of sediment carbon fixation retained by surface-type engineering measures, using formulas (6)-(8) for calculation:

C _plane = Q _plane G _plane Y/1000 (6)

Q _surface = A _surface (X ₀ -X) (7)

X=X ₀ E (8)

In the formula: _surface C is the amount of carbon sequestration and carbon sequestration of surface engineering measures, in t; _surface Q is the annual soil erosion and sand reduction/sedimentation amount in the area of surface engineering measures, and the unit is t/a; _surface G is surface The organic carbon content of the surface soil in the internal area of the engineering measure is in kg/t; Y is the service year of the engineering measure in a; the _surface A is the control area of the surface engineering measure in km ² ; X ₀ is the non-face type Soil erosion modulus of engineering measures, unit is t/(km ² ·a); X is soil erosion modulus of surface engineering measures, unit is t/(km ² ·a); E is engineering measure factor (take The values refer to "China Soil Erosion Equation (CSLE)").

Step thirteen, measure the soil organic carbon content G in the erosion zone in the surface engineering measure control area, _{control erosion} and sediment organic carbon content G _deposition in the sedimentation area; the specific operation is: the erosion collected in the erosion area of the surface engineering measure control area The 5cm soil samples from the surface layer of the soil in the siltation area were collected, and the sediment samples of the entire silt layer were collected in the siltation area, and the organic carbon analyzer was used to measure the soil organic carbon content G _{in the erosion} area and the sediment organic carbon content in the siltation area G _deposition .

Step 14, calculate the total carbon sequestration of engineering measures in the area:

When the sediment transport ratio is not considered, formula (9) is used for calculation:

C=C _surface +C _point (9)

When considering the sediment transport ratio, formulas (10) to (11) are used for calculation:

C＝C _plane SDR+C _point +C _plane (1-SDR)b (10)

b=1-G _deposition /G _{control invasion} (11)

In the formula: C is the amount of carbon sequestration in the region, and the unit is t; SDR is the sediment transport ratio in the control area of engineering measures; G _{control encroachment} is the soil organic carbon content in the eroded area of the control area of surface engineering measures, the unit is kg/t; G _{sedimentation} is the sediment organic carbon content in the deposition area, the unit is kg/t.

In this example:

The calculation data of point-type engineering measures are as follows:

The point engineering measure is to select the check dam, the _maximum storage capacity Q of the check dam is 500t, the measured soil organic carbon content in the erosion area is G _erosion 2.3kg/t, and the measured outlet sediment production S is 400t after the check dam is _full . /a, when the check dam is not built, the measured outlet sediment yield S _is 500t/a, according to the measured layered sedimentation and organic carbon content (Table 1) and formulas (1)-(5), it can be obtained: Sediment Q _{has been} 420t, the amount of carbon sequestration in the silted part C _has been 0.825t, α is 1-400t/a÷500t/a=0.2, the future silting potential Q _{is the largest} - Q is 80t, the total potential Q _potential = ( _Qmax - _Qha )+ _Qmaxα , the calculated Q _potential is 180t, the future carbon sequestration potential of point-type engineering measures _{is not calculated at point} C, which is 0.414, and the carbon sequestration amount of the check dam is C _point = C _{point has been} +C _{point is not} 1.239t.

Table 2 Carbon sequestration amount of deposited sediment

Depth (cm) <![CDATA[Layered deposition volume Q_i(t)]]> <![CDATA[Organic carbon content G_i(kg/t)]]> <![CDATA[Q_i*G_iCarbon Sequestration(t)]]> 0-20 50 2.1 0.105 20-40 70 2.2 0.154 0-60 80 1.5 0.12 60-80 100 1.7 0.17 80-100 120 2.3 0.276

Surface engineering calculation data are as follows:

Terraces are selected for surface engineering measures in this embodiment, and the range of terraces is determined according to remote sensing images (Figure 2). The measured terrace _area A is 0.1km ² . For 24 years (2022-1998), according to the soil samples, the multi-year average organic carbon content of the terraced fields _{in the G plane} is 3.4kg/t. A bayonet station will be built at the regional exit to measure the regional sand production. The sand production without terrace measures It is 20t/a. According to CSLE, the soil erosion modulus X ₀ is calculated as 500t/(km ² ·a) when there are no terraces, and the engineering factor E of stone ridge level terraces is 0.124. According to the formulas (6)-(8), the calculation results are as follows: sediment transport The specific SDR is 0.4, the soil erosion modulus X is 62t/(km ² ·a) after the engineering measures are established, the annual soil erosion and sediment reduction amount Q _of terraced fields is 43.8t/a, and the amount of carbon sequestration by terraced _fields is 3.57 t.

Total carbon sequestration of engineering measures: without considering the sediment transport ratio, the regional carbon sequestration amount C is 1.239t+3.57t=4.809t; in the case of considering the sediment transport ratio, the collection of erosion areas and deposition areas The measured soil organic carbon content is 2.3t/a for G _{control invasion} and 1.5t/a for G _deposition respectively. According to the formula (9)-(11), b is calculated as 0.35, and the carbon fixation amount C in the area is 3.4167t.

Finally, it should be noted that the above is only used to illustrate the technical solution of the present invention and not to limit it. Although the present invention has been described in detail with reference to the preferred arrangement, those skilled in the art should understand that the technical solution of the present invention can be modified Or an equivalent replacement without departing from the spirit and scope of the technical solution of the present invention.

Claims (9)

1. The method for measuring and calculating the carbon sink potential of the soil by the water and soil conservation engineering measure is characterized by comprising the following steps of:

step one, classifying adopted water and soil conservation engineering measures: the method is divided into a surface type measure and a point type measure; the surface type measure is an engineering measure for controlling the soil erosion of the surface scale; the point-type measure is a measure for intercepting and storing corroded sediment;

step two, determining the maximum storage capacity Q of the point engineering measure _{Maximum value} And a stratified sedimentation amount of the blocked sediment amount, the sum of the stratified sedimentation amounts being the blocked sediment amount Q of the dot type Cheng Cuoshi _{Has already been provided with} ；

Calculating sediment storage potential of the part of the point type engineering which is not full of sediment: the sediment blocking amount of the point type tool Cheng Cuoshi is subtracted from the maximum reservoir capacity of the point type tool, namely: q (Q) _{Maximum value} －Q _{Has already been provided with} ；

Calculating the coefficient alpha of other corrosion reducing effects which can be exerted after the spot-type engineering reaches the maximum reservoir capacity:

measuring the layered organic carbon content of sediment in the fixed-point engineering siltation layer and the organic carbon content of soil in an erosion area;

step six, calculating sediment blocking and carbon fixation amount of the spot type tool Cheng Cuoshi: the calculation is performed by using formulas (1) to (5):

C _point(s) ＝C _{The dot has been} +C _{Dot is not} (1)

C _{Dot is not} ＝Q _Potential G _{Erosion of} /1000 (4)

Q _Potential ＝(Q _{Maximum value} -Q _{Has already been provided with} )+Q _{Maximum value} α (5)

Wherein: c (C) _Point(s) The unit is t for blocking sediment and carbon fixation of the spot type Cheng Cuoshi; c (C) _{The dot has been} The carbon fixation amount of the deposited sediment is t for the point-type engineering measure; c (C) _{Dot is not} The future carbon fixation potential is measured by point-type engineering measures, and the unit is t; q (Q) _i The unit of the i layer deposition amount of the deposited sediment is t; g _i The unit of the organic carbon content of the ith layer of sediment is kg/t; q (Q) _{Has already been provided with} The sediment quantity is blocked for point-type engineering measures, and the unit is t; q (Q) _Potential The total potential is blocked by a dotted type Cheng Nisha, and the unit is t; g _{Erosion of} The organic carbon content of soil in the erosion area is kg/t for the point-type engineering measure; q (Q) _{Maximum value} The maximum storage capacity of the spot-type engineering measure is represented by t; alpha is the coefficient of other corrosion reducing effects which can be exerted after the point type engineering reaches the maximum reservoir capacity, the value range is 0-1, and no unit exists; n is the total number of layers of deposited sediment, and no unit exists;

step seven, calculating the service year Y of engineering measures;

step eight, determining the organic carbon content G of the surface soil in the inner area of the surface type engineering measure _In-plane ；

Step nine, measuring the area A of a control area of the surface engineering measure _{Flour with a plurality of grooves} ；

Step ten, respectively establishing a non-surface engineering measure and a surface engineering Cheng Cuoshi runoff district, and measuring the annual total sand production of the district; no-surface type Cheng Cuoshi diameterDividing the annual total sand production of the flowing cell by the cell area to obtain the soil erosion modulus X of the non-surface engineering measure ₀ The method comprises the steps of carrying out a first treatment on the surface of the Dividing the annual total sand production of the area-shaped Cheng Cuoshi runoff district by the area of the district to obtain a soil erosion modulus X of the area-shaped shaping measure;

step eleven, measuring the sand conveying amount and calculating the sediment conveying ratio SDR;

step twelve, calculating the sediment storage and carbon fixation amount of the surface-shaped tool Cheng Cuoshi, and calculating by adopting formulas (6) - (8):

C _{flour with a plurality of grooves} ＝Q _{Flour with a plurality of grooves} G _In-plane Y/1000 (6)

Q _{Flour with a plurality of grooves} ＝A _{Flour with a plurality of grooves} (X ₀ -X) (7)

X＝X ₀ E (8)

Wherein: c (C) _{Flour with a plurality of grooves} The unit of the sediment accumulation carbon fixation quantity is t for the surface type Cheng Cuoshi; q (Q) _{Flour with a plurality of grooves} The unit of the soil erosion sand reduction/fixation amount is t/a; g _In-plane The organic carbon content of the soil on the surface layer of the inner area of the surface type engineering measure is kg/t; y is the service year of engineering measures, and the unit is a; a is that _{Flour with a plurality of grooves} The area of the control area is km for the surface engineering measure ² ；X ₀ The soil erosion modulus is the unit of t/(km) for the non-planar engineering measure ² A); x is the soil erosion modulus of the surface engineering measure, and the unit is t/(km) ² A); e is an engineering measure factor;

thirteenth step, determining soil organic carbon content G in erosion zone in face type engineering measure control zone _{Intrusion control} And sediment organic carbon content G in the sedimentation zone _{Fouling of} ；

Fourteen, calculating the total carbon fixation amount of engineering measures in the area:

and when the sediment transport ratio is not considered, adopting a formula (9) for calculation:

C＝C _{flour with a plurality of grooves} +C _Point(s) (9) When the sediment transport ratio is considered, the calculation is carried out by adopting formulas (10) to (11):

C＝C _{flour with a plurality of grooves} SDR+C _Point(s) +C _{Flour with a plurality of grooves} (1-SDR)b (10)

b＝1-G _{Fouling of} /G _{Intrusion control} (11)

Wherein: c is the carbon fixation amount in the region, and the unit is t; SDR is sediment transport ratio of engineering measure management and control area; b is the carbon ratio lost in the carrying-sedimentation process after the soil is eroded, and is between 0 and 1; g _{Intrusion control} The soil organic carbon content of the eroded area in the area is controlled by the surface engineering measure, and the unit is kg/t; g _{Fouling of} The sediment organic carbon content of the silt area in the area is controlled by the surface engineering measures, and the unit is kg/t.

2. The method for measuring and calculating the carbon sequestration potential of soil by soil and water conservation engineering measures according to claim 1, wherein in the first step, the surface type measure comprises: terrace, horizontal step, horizontal ditch, bamboo joint ditch, fish scale hole, large-scale fruit tree hole, sand barrier sand fixation, engineering protection road, the punctiform measure includes: slope small-sized storage and discharge engineering, ditch head protection, check dam and silt dam.

3. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in the second step, the stratified sediment amount of the blocked sediment amount is selected to be 20cm as one layer, and the ith sediment amount of the sediments is represented as Q _i ，

Q _i ＝A _i ·h _i ·BD _i /1000

Wherein: q (Q) _i The unit of the i layer deposition amount of the deposited sediment is t; a is that _i The bottom area of the ith layer is the unit of square meter for sediment deposition; h is a _i The thickness of the ith layer of sediment is m; BD (BD) _i The unit of the volume weight of the sediment is kg/m for the ith layer of the sediment ³ 。

4. The method for measuring and calculating the carbon sequestration potential of soil and water conservation engineering measures according to claim 1, wherein in the fourth step, α=1- (S) _{Full of} /S _{Not yet} ) Wherein: s is S _{Full of} The sand production amount is exported for the point-type engineering measure after the point-type engineering measure is full; s is S _{Not yet} And outputting the sand production amount when the point-type engineering measures are not built.

5. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in the fifth step, the specific operation of measuring the layered organic carbon content of the silt in the site-specific engineering siltation layer and the organic carbon content of the soil in the erosion area is as follows: the point-type engineering sample of the sediment of the whole siltation layer is collected, and the organic carbon content G of the ith layer of the siltation sediment is measured by using an organic carbon analyzer in a layered manner _i Taking 20cm as a layer; the organic carbon content of the soil in the erosion zone is determined by using an organic carbon analyzer according to a collected 5cm soil sample on the soil surface layer of the erosion zone, and the organic carbon content of the soil in the erosion zone is expressed as G by using point-type engineering measures _{Erosion of} 。

6. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in the eighth step, the organic carbon content G of the surface soil in the inner area of the surface engineering measures is measured _In-plane The specific operation is as follows: collecting a soil sample with the surface layer of 5cm in the inner area of the surface engineering measure, and measuring the organic carbon content G of the soil by using an organic carbon analyzer _In-plane 。

7. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in the step ten, the specific operations of establishing a non-planar engineering measure and a planar engineering Cheng Cuoshi runoff plot and measuring the annual total sand production of the plot are as follows: the non-surface engineering measures are the same as those of the surface engineering Cheng Cuoshi runoff plot except the engineering measures, sediment collecting and accumulating equipment is placed below the plot, sediment in the runoff is collected, the sediment is collected and weighed after each rainfall, each sediment production amount is obtained, and the sum of each sediment production amount in one year is the total sediment production amount in one year.

8. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in the eleventh step, the concrete operation of measuring the sediment transport ratio SDR is as follows: and a bayonet station is arranged at an outlet of the area, sediment collection and storage equipment is arranged, sediment in runoff is collected, the sediment is collected and weighed after each rainfall, each time of sediment transport is obtained, the sum of each time of sediment transport in one year is the total sediment transport in one year, and the ratio of the total sediment transport to the total sediment production is the sediment transport ratio SDR.

9. The method for measuring and calculating the carbon sequestration potential of soil in soil and water conservation engineering measures according to claim 1, wherein in step thirteen, the soil organic carbon content G of the eroded area is measured in the area of control of engineering measures of surface type _{Corrosion control} And sediment organic carbon content G in the sedimentation zone _{Fouling of} The specific operation is as follows: soil samples of 5cm of the soil surface layer of the erosion zone are collected in the erosion zone of the surface engineering measure control zone, sediment samples of the whole sedimentation layer are collected in the sedimentation zone, and the organic carbon content G of the soil of the erosion zone is measured by an organic carbon analyzer respectively _{Corrosion control} And sediment organic carbon content G in the sedimentation zone _{Fouling of} 。

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