Social Benefit Analysis of Disaster-affected Land Reclamation from Micro-quantitative Perspective

After the implementation of the disaster-stricken land reclamation project, it will inevitably have a certain impact on society, but this impact may be positive or negative. Therefore, it is necessary to eliminate the negative impact in the process of project implementation in order to strive for the greatest social benefits. There are many indicators that can be used as social benefit evaluation. According to the characteristics of the affected land and the experience of social benefit evaluation of land reclamation projects at home and abroad, the indicators are selected. Of course, according to the analysis of specific projects, different projects, different types of damage and different degrees of damage will have different evaluation indicators, quantity and focus. See Table 9-3 for the social benefit evaluation indexes of land reclamation after the disaster selected in this paper.

Table 9-3 Social Benefit Evaluation System of Disaster-affected Land Reclamation

The relevant operation formula of each evaluation index is:

1. Reclamation rate of damaged land

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The reclamation rate of affected land is an important indicator reflecting the effectiveness of regional land reclamation, and it is also the only indicator that is not evaluated by a single project, that is, the proportion of reclaimed land area to the land area that needs reclamation.

2. New cultivated land and new cultivated land rate

After the implementation of the project, the amount of newly-increased cultivated land is generally regarded as an important indicator reflecting the feasibility and importance of the project, and it is also an indicator reflecting the impact of the project implementation on social benefits. These formulas are as follows:

New cultivated land area = cultivated land area after reclamation-cultivated land area before reclamation (9-23)

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The most important purpose of land reclamation after the disaster is to restore the arable capacity of cultivated land, improve the quality of cultivated land and increase the effective area of cultivated land. Therefore, the amount of newly-increased cultivated land after the implementation of the project is an index reflecting the social benefits and influence degree of the project. The scale of land development and consolidation projects must meet certain requirements before they can be established. Taking state-invested projects as an example, according to the Interim Measures for the Administration of State-invested Land Development and Consolidation Projects, the requirements for reporting key state-invested projects are as follows:

(1) land development. The scale of construction in hilly and mountainous areas is between 100 and 600 hectares, and the projects should be concentrated and contiguous as far as possible, with a single area of not less than 20 hectares and not more than10; The plain area is between 400 and 2000 hectares, and the projects are relatively concentrated and contiguous, with a single area of not less than 50 hectares and not more than 10.

(2) Land consolidation. The construction scale of hilly and mountainous areas is between 100 and 1000 hectares, and the projects should be concentrated and contiguous as far as possible, with a single area of not less than 40 hectares and not more than 10; The plain area is between 400 and 2000 hectares, and the projects are relatively concentrated and contiguous, with a single area of not less than 60 hectares and not more than 10.

(3) Land reclamation. The scale of construction in hilly and mountainous areas is between 60 and 400 hectares, and the projects should be concentrated and contiguous as far as possible, with a single area of not less than 20 hectares and not more than 10; The plain area is between 200 ~ 1000 hectares, and the project is relatively concentrated and contiguous, with a single area of not less than 60 hectares and not more than 10.

The requirements of new cultivated land rate are: the area of new cultivated land for land consolidation is generally not less than10% of the project construction scale area; The net increase of cultivated land area in land reclamation is generally not less than 40% of the project construction scale area; The net increase of cultivated land area in land development is generally not less than 60% of the project construction scale area.

To apply for subsidy projects in disaster areas, the construction scale requirements: the projects should be concentrated and contiguous as far as possible, with more than 0/00 hectare in hilly and mountainous areas and more than 200 hectares in plain areas.

3. Land use growth rate

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Land utilization rate refers to the ratio of the utilized land area within the reclamation scope to the total land area of the region, which is generally expressed as a percentage. The growth rate of land use is a quantitative index to reflect the degree of land use after reclamation, and its level depends on many factors such as reclaimed land area, local natural conditions, economic conditions, land use technology level, production relations, social system and so on.

4. Growth rate of grain output

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The food problem is undoubtedly one of the basic national conditions and a top priority related to people's livelihood. According to the article Trend Analysis and Data Reconstruction of Cultivated Land Resources in China, from 20 10, the decrease of cultivated land resources in China will gradually decrease. With the development of land improvement project and the completion of ecological conversion of farmland, the amount of cultivated land will be in a good state, and with the development of agricultural technology, the grain output will inevitably increase.

5. The number of newly-increased cultivated land can be supported.

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Judging from the current situation in China, the most basic social security for farmers is cultivated land. On the one hand, the implementation of reclamation project has increased the per capita cultivated land area and improved the basic social living standards of farmers; On the other hand, the quality of cultivated land resources in the project area has been improved to some extent. In real life, the calculation of new cultivated land can reflect the social benefits brought by the implementation of the project. The more people can support, the higher the improvement degree of farmers' basic social life security in the project area, and the greater the social benefits brought by the project. The more the number of landless farmers in the disaster area, the more obvious the social benefits brought by the new cultivated land after the implementation of the project.

6. Improve the road access rate

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Road accessibility is to evaluate the accessibility of a regional traffic network. Roads can further improve the production and living conditions of residents in the project area, make full use of the original road subgrade, avoid occupying agricultural cultivated land and forest land, focus on improving the smoothness of the road surface and the disaster-resistant drainage capacity of the road surface, improve the road construction standards for areas with good road conditions, harden the road surface, build drainage ditches and improve the road drainage conditions. This index is realized through field road engineering and is an important index reflecting the improvement of production and living conditions in the project area.

7. Improve the utilization rate of water conservancy facilities.

Improvement rate of water conservancy facilities utilization rate = utilization rate of water conservancy facilities after reclamation-utilization rate of water conservancy facilities before reclamation (9-29)

Although the total amount of water resources in China is relatively large, the per capita water resources are only 2 100 cubic meters, and the per mu water resources are only 1400 cubic meters, accounting for 28% and 50% of the world average respectively. It is characterized by uneven distribution of water resources in time and space, small population and land, low utilization rate of fresh water resources, serious soil erosion, fragile water ecological environment and frequent natural disasters. 60% ~ 80% of precipitation and river runoff in most areas are concentrated in flood season, and there are often rainy years or dry years for several years. The distribution of water resources in China is extremely uneven between the north and the south. The land area in the north accounts for 64% of the country, of which cultivated land accounts for 60%, population accounts for 46% and regional GDP accounts for 45%. However, water resources only account for 19% of the whole country. After reclamation, the utilization rate of water conservancy facilities is improved through irrigation and drainage projects, which can not only ensure the sustainable development of agricultural production water sources in the project area and prevent flooding, but also improve the water utilization coefficient of canal system and improve the ecological environment of the project area.

8. Multiple cropping index increased

Multiple cropping index increase = multiple cropping index after reclamation in the project area-multiple cropping index before reclamation in the project area (9-30)

Multiple cropping index refers to the average number of crops planted on the same plot in a certain period of time (generally 1 year), that is, the average number of crops planted on cultivated land in a year or the proportion of total sown area of crops to cultivated land in a year. Multiple cropping index reflects the level of multiple cropping and is used to compare the utilization of cultivated land in different years, regions and production units. The multiple cropping index of cultivated land is affected by local labor force, heat, scientific and technological level, soil, water and fertilizer. Good heat condition, high total accumulated temperature, long frost-free period and sufficient water are the basis to improve the multiple cropping index of cultivated land. The high level of agricultural science and technology and developed economy have created conditions for the improvement of multiple cropping index of cultivated land. Generally speaking, the water and heat conditions in southern China are good and the utilization rate of cultivated land is high. In most areas of Hubei, Hunan, Jiangxi, Zhejiang, Fujian, Guangdong and other provinces, the multiple cropping index of cultivated land is above 200%. Improving the multiple cropping index of cultivated land plays an important role in the development and increase of agricultural production. At present, the area of multiple cropping cultivated land in China accounts for about 1/2 of the total cultivated land in China, and the area of multiple cropping sowing accounts for about 1/2 of the total sown area. The main types of multiple cropping are: rice and wheat (rape), wheat and corn, wheat and cotton, and wheat and sweet potato. In recent years, Sichuan, Guizhou, Yunnan, Hubei, Hunan, Fujian and other provinces have developed the wheat-rice-ratooning rice planting model, making full use of natural resources such as water, gas, light and heat. Multiple cropping index of cultivated land can comprehensively reflect the implementation of land leveling project, irrigation and drainage project and field road project in reclamation projects, and it is also an important index to fully tap the potential of cultivated land, improve the quality of cultivated land and enhance land use efficiency.

9. Increase in per capita net income

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In the evaluation of social benefits, it is very necessary to analyze the changes of farmers' income after the implementation of the project. Because, the benefits of reclamation project should not only be reflected in the index of increasing cultivated land area and improving cultivated land quality, but also in the final result of increasing local farmers' production and income, which can directly reflect the degree of farmers' income in the project area, thus helping to improve production and living conditions and fully mobilizing and improving farmers' enthusiasm for participating in engineering construction and agricultural activities. Determining farmers' income after the implementation of the project can be realized by calculating the increase of per capita annual net income.

10. Production efficiency

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An important reason for the large income gap between urban and rural areas in China is the low agricultural labor productivity, which is particularly obvious in disaster areas. After the implementation of the disaster-stricken land reclamation project, on the one hand, it will accelerate the development of agricultural mechanization in the disaster area, improve the output per unit area of agriculture in the disaster area and the productivity effect of the project area; On the other hand, it will greatly promote the transfer of agricultural labor productivity in reclamation areas to secondary and tertiary industries. The degree of productivity improvement can be measured by calculating the improvement of agricultural labor productivity after the implementation of the project. The index value is directly proportional to the social benefits of project implementation. The greater the index value, the better the benefit. If the index value is equal to or less than 0, the project is not feasible.

1 1. Poverty alleviation effect

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Although China has announced the goal of basically eliminating poverty by the end of 2000, the poverty situation in some parts of the country is still very serious, especially after the disaster. Through various forms, the state and relevant units give support to these areas in terms of production conditions, infrastructure and employment opportunities, so that they can rely on their own production development and finally get rid of backwardness and poverty. Calculate the regional poverty alleviation rate after the implementation of the project according to the corresponding poverty alleviation living standards formulated by various places. Poverty alleviation rate is directly proportional to social benefits. The greater the poverty alleviation rate, the better the poverty alleviation effect after the implementation of the project and the greater the social benefits.

The initial social benefits of the affected land reclamation project are first reflected in reducing natural disasters, for example, protecting new land from gully erosion, desertification and petrochemical damage; Reduce the flood disaster, soil erosion and sediment hazard in the downstream of the reclamation area; Reduce the risk of landslides and mudslides; Reduce the harm of wind-blown sand and wind erosion in reclamation areas. At present, the conditions for generating social benefits and promoting social progress are not available. In the middle and later period of reclamation, the reclaimed area has already possessed the production function, and its social benefits are not only reflected in reducing natural disasters, but also in promoting social progress, increasing cultivated land area, alleviating the contradiction between people and land, making unemployed and landless farmers and their surplus labor useful, improving labor utilization, improving agricultural infrastructure, improving land productivity, improving environmental capacity, adjusting land use structure and agricultural industrial structure, adapting to market economy, and promoting farmers to get rid of poverty and become rich and run towards a well-off society. At the same time, after transforming land, rebuilding soil and restoring vegetation, it not only ensures the "dynamic balance of total agricultural land", but also rebuilds an ecosystem equivalent to or even better than the original ecosystem, which promotes social harmony and stability.