Method for estimating compensation amount

The ecological compensation amount for water and soil conservation in the supervision area cannot be lower than the input cost of preventing and controlling water and soil erosion due to production and construction activities. The ecological value lost due to water and soil erosion caused by production and construction activities should be the upper limit of the compensation amount. As shown below. After determining the scope of ecological compensation for soil and water conservation, the compensation subjects and objects should negotiate and determine the compensation plan based on factors such as regional economic development level.

Figure 10-1 Value range of ecological compensation for soil and water conservation in the supervision area

1. Comprehensive prevention and control costs of soil and water loss

Comprehensive prevention and control of soil and water loss in production and construction activities Measures mainly include engineering measures and biological measures. The cost is the arithmetic sum of the costs of each individual measure. The cost of each individual measure is the value of each individual measure multiplied by the material data (or) price (labor fee) of the current period of production and construction. Namely

Research on ecological compensation for soil and water conservation

In the formula: C is the investment cost of comprehensive prevention and control of water and soil loss in the supervision area; Ki is the amount of individual project measures, and Pi is the current single project of production and construction activities Measure price; Tj is the amount of a single biological measure, and Pj is the price of a single biological measure in the current period of production and construction activities.

2. Ecological value lost by water and soil erosion

The ecological value lost by water and soil erosion mainly considers the soil loss caused by water and soil erosion in the upstream, the loss of water source conservation functions and the siltation loss of downstream rivers, lakes and reservoirs. The losses are as follows The formula is shown:

Research on ecological compensation for soil and water conservation

In the formula: L is the ecological value of water and soil loss; Ls is the value of soil loss; Lw is the value of water conservation function loss; Ln is Siltation losses in rivers, lakes and reservoirs.

(1) Value of soil loss

1. Amount of soil loss

The amount of soil loss is the basis for calculating various types of losses due to water and soil loss. The amount of soil loss can be used as follows: Calculation formula:

Research on ecological compensation for soil and water conservation

In the formula: SL is the amount of soil loss, Ai is the average annual soil erosion intensity of the unit, and Si is the area of ??the unit.

Ai can be calculated using the Universal Soil Loss Equation (USLE). This equation takes into account five major factors: rainfall, soil erodibility, crop management, slope length and soil and water conservation measures, as follows:

Research on ecological compensation for soil and water conservation

Among them, A is the annual average soil loss intensity (t/hm2), R is the rainfall and runoff erosion factor, K is the soil erodibility factor; LS is the terrain factor, where L is the slope length factor, S is the slope factor; C is the crop management factor , P is the governance measure factor.

However, it is currently difficult to obtain the massive data on national climate, topography and vegetation coverage required for the calculation of this formula, so the following approximate formula is used instead:

Research on Ecological Compensation for Soil and Water Conservation< /p>

In the formula: SL is the amount of soil loss, Ssj is the area of ??various types of water and soil loss in each unit, Sej is the intensity of various types of water and soil loss; Sejmax and Sejmin are the upper and lower limits of each erosion intensity classification standard, Ti is the allowable soil loss value for each unit.

According to the "Soil Erosion Classification and Grading Standards" (SL 190-96), the value standards for Sejmax, Sejmin and Ti are as shown in the table below.

Table 10-1: Allowable soil loss scale for each erosion type area

Table 10-2: Soil erosion classification and grading standards (SL 190-96)

2 .Economic losses from soil loss

According to the views of Mao Zhifeng and others, on the basis of measuring the amount of soil loss, the market value method, protection cost method, and restoration cost method can be used to calculate the economic losses of soil respectively. value.

(1) Market value method

The lost soil can be used as building materials, ceramics and other raw materials. Therefore, it has direct use value and can be measured using the market value method. The calculation formula is as follows:

Research on ecological compensation for soil and water conservation

In the formula: ELs is the economic loss of soil loss, and Psi is the economic loss of soil loss. The resource price of sediment in the loss area, SLi is the amount of soil loss in the loss area.

(2) Protection cost method

The loss of sediment loss can be measured by the construction cost of the protection project. Calculations based on different protective measures yield different losses. Sediment loss can be controlled through measures such as building terraces and protective forests. If measured based on terraces, the protection cost is the investment cost of building terraces, that is, the economic loss of sediment loss in a certain area is the amount of soil loss in the area (m3/a) and the investment cost of the project to intercept each m3 of sediment. The product of (yuan/m3):

Research on ecological compensation for soil and water conservation

In the formula: Ppi is the cost of the terrace project per unit in each loss area; SLi is the amount of soil loss in each loss area .

(3) Restoration cost method

Sediment loss causes losses to the loss area, and the loss can be compensated for by restoring the loss area in a certain way. Accordingly, the cost of restoration measures can be used to measure the loss of sediment loss. The same quality of sediment is transported (purchased) from elsewhere, and then the sediment is distributed and fixed through artificial measures. Through this measure, the amount of sediment in the lost area can be restored.

Therefore, the calculation formula of the restoration cost method is as follows:

Research on ecological compensation for soil and water conservation

In the formula: Psi is the market price of sediment in each loss area, Li is the restoration of each loss area The labor required per unit of soil, Pi is the labor price, and SLi is the amount of soil loss in the loss area.

(2) Calculation of water conservation loss

1. Calculation of water conservation loss

The water conservation amount of soil is determined by soil structure, soil layer thickness, and ground slope. Determined by factors such as rainfall amount and frequency. Precipitation below moderate rain generally does not form obvious surface runoff, but in heavy rain and above, the water content of the soil reaches a saturated state, and the soil's function of conserving water sources can be maximized. Based on this, the calculation formula for soil water conservation loss can be written in the following form:

Research on Ecological Compensation for Soil and Water Conservation

In the formula: WL is the soil water conservation loss, Si is unit i The soil erosion area, ΔHi is the average soil erosion thickness, Ci and ci are the soil saturated water content and general water content respectively, fi is the frequency of precipitation above heavy rain.

2. Calculation of economic losses of water source conservation

(1) Shadow engineering method

The loss of water source conservation function can be made up by building reservoirs. Accordingly, the water source The conservation loss can be calculated by the following formula:

Research on Ecological Compensation for Soil and Water Conservation

In the formula: ELw is the economic loss of water source conservation, Ppi is the cost of the unit reservoir project in each loss area, and WLi is the cost of each reservoir project in each loss area. The amount of water conservation loss in the loss area.

(2) Protection cost method

In order to prevent the decline of soil conservation water source function, the construction of shelterbelts can play a protective role, and the loss of soil conservation water sources can be covered by the cost of building corresponding shelterbelts To measure:

Research on ecological compensation for soil and water conservation

In the formula: Ppi is the cost of the protective forest project per unit in each loss area, and WLi is the water conservation loss in each loss area.

(3) Calculation of siltation loss in rivers, lakes and reservoirs

Sediment is transported from the upstream loss area to rivers, lakes and reservoirs for redistribution, causing siltation. Certain engineering measures or biological measures can be used Prevent sediment from entering rivers, lakes and reservoirs. For example, water retention sand dams can be built to block upstream sediment, terraces can be built in the upstream loss areas or vegetation can be added to reduce sediment loss. Rivers can also be cut and straightened to reduce sedimentation. The method of building sediment dams is used to calculate, and the formula is:

Research on ecological compensation for soil and water conservation

Where: ELm is the economic loss caused by sedimentation in rivers, lakes and reservoirs, Ppi, is the cost of unit sediment retention projects in each loss area; SLi is the amount of soil sedimentation in rivers, lakes and reservoirs.

The sedimentation of reservoirs has led to the reduction of reservoir storage capacity and the weakening of its water supply, irrigation, flood control, power generation and other utilization functions. In theory, if a reservoir becomes obsolete due to siltation, a new reservoir can be built to replace the various functions of the original reservoir. Therefore, the shadow engineering method can be used to evaluate the sedimentation loss of the reservoir, that is, the economic loss caused by the sedimentation of the reservoir is measured by the investment required to build a new reservoir with the same storage capacity.

Research on ecological compensation for soil and water conservation

In the formula: Ppi is the cost of the reservoir project per unit in each loss area, and CLi is the storage capacity loss caused by siltation.