Engineering test of rocky desertification geological environment control

Adhering to the principle of "people-oriented", guided by the related theory of "Geological Model for Rocky Desertification Control", we should start with improving the geological environment of rocky desertification, strive to improve the ability of geological resources to ensure economic and social development and improve the ecological environment, promote regional economic and social development, and finally realize comprehensive management of rocky desertification, providing practical basis for the establishment of geological model for rocky desertification control and providing demonstration projects for comprehensive management of rocky desertification in karst mountainous areas.

Second, the principles of governance plan formulation

The design of rocky desertification control project in Jumu underground river basin follows the following principles:

1) The principle of adapting to local conditions. Fully consider the characteristics of local resources and development and utilization conditions, so that valuable geological resources can be effectively utilized.

2) The principle of economic feasibility. Governance projects should strive to save investment, low operating costs, and be accepted by the masses.

3) The principle of combining with ecological environment protection. The development of resources will not cause damage to the environment, and efforts will be made to "promote benefits and eliminate pests".

4) The principle of combining with economic and social development. The project is based on solving the problems of rural drinking water safety and farmland irrigation and improving the local economic development level.

Third, the overall scheme of the experimental project

The overall planning of rocky desertification geological environment improvement is based on the investigation of groundwater and geological environment in advance and the basic identification of geological, environmental hydrogeological conditions, characteristics of groundwater resources, development and utilization conditions and geotechnical geochemical background.

The remediation plan mainly consists of three parts: groundwater development and utilization project, rock geochemical background development and crop mineral element compensation planting project, and flood depression treatment and development project (land consolidation combined with ecological migration). At the same time, remote sensing technology is used to monitor the development trend of rocky desertification in the experimental area before and after the implementation of the control project, which provides a basis for testing the effect of rocky desertification control and demonstrating the feasibility of geoscience model.

(a) the groundwater development and utilization project plan

According to the characteristics of the dynamic change of groundwater in the basin, but the underground space has strong water storage capacity, the annual average flow of underground river is large but the outlet elevation is low, the karst drought in the downstream of the outlet of underground river and the karst flood in the upstream, the underground river is blocked into a reservoir. The underground reservoir area is used to regulate water resources, and the potential energy of water level raised in front of the dam is used as the power to lift water. Combine water storage project, water lifting project and water delivery project to develop groundwater and supply water to Tangbian Town and Kedu Town in Pingtang County where population and cultivated land are concentrated, so as to solve the problems of drinking water for people and livestock and irrigation water for farmland respectively. Therefore, the underground river development and utilization project in the demonstration project consists of three parts: water storage project, water lifting project and water delivery project (Figure 3- 12).

1. Water storage project

Combined with the development conditions of water resources and the distribution characteristics of cultivated land, the water storage project consists of underground and surface reservoirs.

Figure 3- 12 Layout of Groundwater Development Scheme

The first-class (main) water storage project is to build an underground reservoir by damming at the outlet of the underground river. The design elevation of dam crest fully considers the fact that the relative height difference between the outlet elevation of underground river (865,438+05m) and the submerged dam depression (845m above sea level) is relatively small. In order to avoid the inundation of the dam depression caused by the high backwater level in the reservoir area after the impoundment of the underground reservoir, the impoundment elevation of the underground reservoir is limited to 828m above sea level, that is, the water level is raised to 13m.

The dam site of the secondary reservoir is built at the surface valley 1.2km downstream of the underground river outlet, which makes up for the problem that the dam of the primary reservoir cannot be designed too high due to the height limitation of the flood depression in the upstream area, resulting in the limited storage capacity and insufficient regulation of the underground reservoir.

2. Water lifting project

Due to the limited water storage elevation of the reservoir, only the drainage of the dam head channel can solve the farmland below 828 meters elevation, while the farmland, market towns and villages in the experimental area are mainly concentrated between 820 and 850 meters above sea level. Therefore, the groundwater development project must be combined with the water pumping project in order to give full play to its benefits. Considering the economic development level of the experimental area and people's affordability, in the design scheme, fully consider reducing the operating cost and avoiding using electric machinery to lift water. Instead, it uses the water energy formed by the rising water level in front of the underground reservoir dam and the large flow of underground river to lift water, and then transports the groundwater to the high-level pool through the hydraulic pump, and then transports the groundwater from the high-level pool to the water supply target through the water diversion project. This can not only solve the drinking water problem of people and animals in Tangbian, Kedu and adjacent villages, but also cover the farmland in the whole experimental area at altitude.

3. Water conveyance project

According to the topographical conditions and the purpose of water supply, it consists of water pipes, inverted rainbow pipes, aqueducts, water main canals and bucket canals. Among them, from the perspective of drinking water safety, all the drinking water transportation projects for people and animals adopt closed pipes; Farmland irrigation water is mainly delivered by open channels, and pipes, canals, caves and flood diversion pipes are combined, making full use of the "irrigation canal system of Tianshengqiao power station irrigation area" built in the experimental area to form a perfect irrigation system.

(2) Geotechnical geochemical background development and mineral element compensation planting engineering scheme.

According to the investigation results of the spatial distribution of silicate rocks and carbonate rocks in the experimental area, as well as the composition and content of geotechnical mineral elements and nutrient elements, the first is to put forward suggestions on the adjustment of agricultural planting structure layout in the experimental area, and the second is to carry out compensation planting experiments of crop mineral elements. Select a certain area of cultivated land, use the "trace element mineral fertilizer" extracted from silicate rocks to compensate crops in carbonate rock distribution areas, explore ways to improve agricultural production environment, improve land yield and crop quality in karst mountainous areas from a geoscience perspective, and demonstrate agricultural production in carbonate rock distribution areas.

(3) Flood control development project plan

The purpose of flood and waterlogging depression control is to restore and utilize the land abandoned by flood and waterlogging, and at the same time, flood and waterlogging depression is used as the base of rocky desertification ecological control and resettlement. The project includes three parts: flood control and drainage project, land consolidation project and ecological resettlement project.

1. Drainage Works in Depression

The experimental area of karst flood depression treatment engineering is located in the overflow dam near the downstream exit of Jumu underground river. Before the implementation of the project, on the basis of geological investigation and exploration of the depression and its adjacent areas, and on the basis of basically finding out the karst hydrogeological and engineering geological conditions of the depression and its surrounding areas, especially the genetic type, spatial distribution and upstream water intake and drainage capacity of the karst pipeline, a flood discharge channel connecting the skylight of the upstream underground river and the downstream undercurrent entrance will be built in the floodplain. The karst pipeline in the entrance area of the subsurface flow is dredged, and the flood discharge tunnel is excavated along the exit direction of the underground river. In rainy season, the underground water level rises and leads to the underground river upstream of the depression.

2. Land consolidation project

On the basis of drainage engineering treatment of flooded dam and waterlogged depression, land consolidation is carried out to restore cultivated land.

3. Ecological migration project

After the farming conditions are restored, the population in the rocky desertification area can be relocated and resettled by using the flooded karst depression, which can improve the production and living conditions of the population in the rocky desertification area and promote poverty alleviation. On the other hand, it ensures the effective implementation of ecological restoration projects such as closing hillsides to facilitate afforestation, planting trees and returning farmland to forests in rocky desertification areas after immigration.

Four, the implementation of the experimental project and its main achievements

According to the investment of engineering funds, the experimental project is completed in two phases. The first phase includes groundwater development project, geotechnical geochemical background development and mineral element compensation planting project. Because of the high investment, the flood control development project is implemented as the second stage.

By the end of 2006, the first phase of the project had been completed.

(1) groundwater development project

The groundwater development project is based on the completion of hydrogeological and engineering geological survey, topographic survey, underground river tracing test, geophysical exploration, engineering geological drilling, water pressure test and rock physical and mechanical analysis in the underground river basin, and the submission of the Engineering Geological Exploration Report of Jumu Underground River in Pingtang County, Guizhou Province and the Feasibility Study Report of Jumu Underground River Karst Groundwater Resources Development Project in Pingtang County, Guizhou Province.

1. Underground Reservoir Project

(1) Construction conditions of underground reservoir project

The Exploration and Feasibility Report analyzes and expounds the engineering geological conditions of underground reservoir construction as follows:

1). (1) regional stability. The basic earthquake intensity in the experimental area is less than ⅵ, and the regional crust is stable. According to the engineering exploration in the hub area, there is no fault structure in the dam site area, the right abutment is mountainous with thick bedrock, the left abutment is hilly, and the bedrock is thick layered limestone of Permian Maokou Formation (P2m). In the exploration, in the 1 borehole, only one dissolution fracture was found at a depth of more than 20 meters, and the clay was completely filled. The rock mass of dam foundation is integral and of good quality. ② Stability of dam area. There is no fault structure in the dam site area. The dam foundation and abutment are thick layered limestone of Permian Maokou Formation, which belongs to hard rock. Rock mass of dam foundation is generally intact, with rock quality designation (RQD) value exceeding 70% and excellent rock quality. There are no geological disasters such as landslides and mudslides in the dam area, but the outlet of the underground river is located under the steep cliff, and ancient collapse accumulation bodies are distributed at the foot of the steep cliff. There is no big unloading crack in the steep cliff area, and the slope is generally stable at present. ③ Stability of reservoir area. There is no steep slope on the surface of the proposed underground reservoir area, and the underground karst space is fully used for reservoir water storage, so there is no stability problem in the reservoir area.

2) Analysis of underground reservoir leakage. In order to find out the engineering geological conditions of the dam site area, special engineering geological exploration and test work were carried out in the dam site area. See Figure 3- 13 for the drilling layout of the exploration project. ① Analysis of dam foundation leakage. The riverbed in the design dam base area is all the bedrock of Permian Maokou Formation (P2m), and only the surface on both banks of the riverbed is covered by Quaternary (Q). The engineering geological rock group of Quaternary loose rocks is composed of brownish yellow residual silty sand and clayey silty sand, containing gravels or alluvial gravels, with loose structure and discontinuous distribution, thickness of 0.0 ~ 12. 1 m, and bearing capacity characteristic value of 220.22kpa.. The Permian Maokou Formation (P2m) belongs to hard rock engineering geological strata, with limestone lithology and uniaxial saturated compressive strength of 55.740 ~ 86.007 MPa. The individual forms of rock karst revealed by drilling are small dissolved cracks and dissolved holes. The fracture is completely filled with clay, the fracture surface is impregnated with iron, and calcite crystals can be seen in the dissolved pores, indicating that the groundwater activity is weak. The water pressure test of dam foundation rocks (Figure 3- 14) shows that the permeability of Permian Maokou Formation (P2m) limestone at different depths is generally poor, and its unit water absorption is shown in Table 3-4. Due to the loose rockfall accumulation on the dam site surface, it is required that the dam foundation must be placed on the fresh and flat bedrock surface of the river bed, and the foundation cleaning must be in place to prevent the dam foundation from leaking. ② Analysis of dam abutment leakage. The contact zone of the right abutment of the proposed dam is Permian Maokou Formation (P2m) limestone. There are two groups of fractures in the northeast and northwest of the shallow surface, with the development density of 0.6 ~ 1.2/m, which are basically unfilled, with strong openness and connectivity and poor rock integrity. Therefore, the abutment of the proposed dam must be embedded in fresh bedrock. The left abutment ZK8 hole is exposed to the karst cave, and a large amount of drilling flushing fluid leaks, and the leaked flushing fluid overflows to the adjacent river valley, indicating that there is the possibility of karst leakage in the left abutment, which must be effectively treated before dam construction to prevent the abutment from leaking. ③ Analysis of leakage around the dam. According to the investigation, both sides of Jumu underground river system are underground basins, and the water outlet area extends to both sides along the dam axis. The farther away from the river bed, the higher the groundwater level. According to the design backwater elevation of 828 meters in the reservoir area, the leakage around the dam can be basically eliminated after the dam is completed. ④ Analysis of adjacent valley leakage. The surface watershed elevation between Jumu underground river and the west mixed underground river adjacent to the east is1097 ~1165m, and the designed backwater elevation of underground reservoir is 828m, which is lower than the watershed elevation between the two underground rivers. According to the hydrochemical test results of the underground river tracing test, the concentration of Cl- in the water samples at various observation points of Jumu underground river is less than 0.05538 mg/L, and the concentration of Cl- in the observation point of Xixi underground river is 0.02769 mg/L, which shows that under natural conditions, the two underground rivers are independent systems and have no hydraulic connection. Therefore, in the range of design backwater elevation, the possibility of leakage in the adjacent valley of underground reservoir is small. The watershed elevation between Jumu underground river and Buwai underground river on the west side is 850 meters above sea level, which is also higher than the designed reservoir storage elevation, and the possibility of underground reservoir leakage to the adjacent Buwai underground river valley is also small.

Figure 3- 13 Layout of Dam Site Exploration Project

Figure 3- 14 Layout of Hydrostatic Test Project in Dam Area

Table 3-4 Statistical unit of borehole water absorption: L/(min m-2)

3) Analysis of regulation capacity of underground reservoir.

① Estimation of storage capacity. The spatial structure of underground karst water system is usually complex and changeable. Trying to master and understand the internal structure of underground river system in detail requires a lot of exploration, experiments and research work, which is difficult and the effect is not necessarily satisfactory. At present, the construction of underground reservoirs at home and abroad mostly obtains accurate storage capacity data through actual water discharge test after the completion of underground reservoirs, but this may bring great blindness to the feasibility evaluation and engineering design of underground reservoir construction, and have a great impact on the technical and economic rationality of engineering layout, design and construction. Dams are built in underground rivers to stop water and build reservoirs, and the underground water storage space is mainly caves, dissolved holes and cracks associated with them in underground rivers and water-bearing rocks. Therefore, the water storage capacity of underground reservoirs is estimated by the geometric shape generalization method of underground river storage space, and the calculation formula is as follows

Study on Geo-model of Karst Rocky Desertification Control

Where: V is the designed storage capacity of underground reservoir (m3); V 1 is the volume of underground river pipeline submerged by backwater (m3); V2 is the pore volume (m3) of the rock mass submerged by backwater.

These include:

Where: h is the head in front of the designed underground reservoir dam (m); Average width of underground river water storage pipeline (m); L is the length of backwater area (m).

From the submerged dam in the lower reaches of Jumu Underground River to the exit area, the tributaries of the underground river have basically merged into the main runoff pipeline, so it can be approximately considered that the underground river pipeline in this area is single-branch. After the completion of the underground reservoir, the rock mass in the whole reservoir area can be regarded as a water-bearing body filled with water, and the water-filling range formed by the backwater length of the underground river can be approximately regarded as a triangular cone. Therefore, V2 is calculated by the following formula:

Study on Geo-model of Karst Rocky Desertification Control

Where: I is the longitudinal hydraulic gradient of underground river; J is the hydraulic gradient of groundwater discharged from the aquifer of vertical underground river pipeline to underground river; μ is the unit output; H is the head in front of the designed underground reservoir dam.

The water surface elevation of the outlet canal of Jumu Underground River is 8 15m, the elevation of the proposed dam crest is 828m, and the highest water head in front of the dam is 13m. The calculation of V 1 is carried out by combining measured data with speculation. According to the measurement of skylight, shaft and some pipelines along Jumu underground river, the width is between 2.0 ~ 13.5 meters, so it is inferred that the average width of Jumu underground river pipeline from flooded dam to outlet is 6.4 meters. According to backwater elevation and hydraulic gradient of underground river, the backwater length of the reservoir is estimated, which is about 2 kilometers from the exit of Jumu underground river to the submerged dam site. The values of I and J are obtained according to the water level elevation of skylight, exploration borehole and outlet of underground river along the track of underground river and the distance from the measuring point. The longitudinal hydraulic gradient (I) of underground river pipeline is 7.4 ‰, and the hydraulic gradient (J) of aquifer of vertical underground river pipeline is 10. 1 ‰. According to the statistics of karst rate of drilling cores in the exploration of dam foundation at the exit of Jumu underground river and in the exploration of karst depression over dam, the karst rate is 0.0785, which approximately represents the water supply of water-bearing rock group μ. Substituting the above parameters into Formula (3-2) and Formula (3-3), V 1=8.32× 104 m3, and V2=230.75× 104 m3. From this, the storage capacity of underground reservoir is estimated: V=239.07× 104 cubic meter.

② Analysis of regulation capacity of underground river system. The construction of the underground river reservoir not only needs a certain water storage space, but also needs sufficient water supply capacity. According to the dynamic long-term monitoring sequence data of local underground river flow in a hydrological year from September 2003 to August 2004, the flow attenuation equation of local underground river is established as follows.

Study on Geo-model of Karst Rocky Desertification Control

Among them: Qt is the underground river flow at time t in decay period; Q0 is the initial flow of the underground river during the attenuation period; It is time.

During the monitoring period, the flood season of Jumu underground river ended in the middle and late September, and it began to enter the period of flow attenuation until the rainy season came in the late April of the following year, with the attenuation period of about 200 days. Use formula (3-4) to integrate the groundwater flow during the consumption period of the whole underground river system, and get the annual adjustable groundwater resources of the underground river basin system (V):

Study on Geo-model of Karst Rocky Desertification Control

Where Q0 takes the flow of 478. 19 L/s at the beginning of the decay period on September 30th, and finally gets V = 379.4× 104 m3/ year. The analysis results of the storage capacity of the proposed underground river and the groundwater regulation capacity of the underground river system show that the groundwater recharge capacity of the underground river system is much greater than the designed storage capacity, which shows that the underground reservoir is a fully regulated reservoir with strong regulation capacity.

(2) Achievements of underground reservoir construction

From 2003 to 2004, the exploration of Jumu underground river system and the water storage test of outlet dam were completed. After one hydrological year, the test of dam construction was successful, and the benefits were brought into play that year. From 2005 to 2006, on the basis of successful dam blocking test, the underground reservoir construction project was formally implemented and completed. At the exit of Jumu underground river, a slurry block stone gravity dam 1 block was built, with a dam height of13m (excluding the dam foundation) and a dam axis length of 77m, thus completing the construction of underground reservoir.

2. Surface reservoir project

At the same time as the underground reservoir was built, a slurry block stone gravity dam with overflow at the top of the dam was built on the downstream 1.2 km of the Jumu underground river outlet. The elevation of the dam crest is 815.5m above sea level, the dam axis is 40.0m long, the dam height is 3.5m, and the overflow section is15.0m. At the same time, a reinforced concrete flat bridge with a deck width of 3.0m and a design load of 5t is built based on the dam crest.

3. Advanced swimming pool project

65,438+0,300 cubic meters of high-level pools will be built at the hillside elevation of 965,438+00 meters behind the exit of Jumu Underground River, and 65,438+0 high-level pools with capacities of 65,438+000 cubic meters and 200 cubic meters will be built at the left bank of the reservoir head of 845.0 meters and the right bank of 895.0 meters respectively.

4. Water lifting project

Two hydraulic pumps with lift 105 m and rated flow of 90 m3/h are installed at the head of the underground reservoir, and two hydraulic pumps with lift 100 m and rated flow of 30 m3/h are installed. In addition,100qj10x100 deep well submersible pump is installed to ensure normal water supply in extreme drought season.

1 hydraulic pumps are installed on the left and right banks of the surface reservoir respectively, with a lift of 50m and a rated flow of 50m3/h.

5. Water conveyance project

Including drinking water transportation project and farmland irrigation transportation project.

Drinking water transportation project: laying a high-level pool with diameter from Xiangtangbian town and supporting underground reservoir? 150 mm, with a total length exceeding 10 km, is the main tap water supply pipeline for domestic drinking water.

Irrigation and water conveyance project for farmland: the sewer pipe is laid northward from the high-level pool supporting the underground reservoir, and meets the south main canal of Tianshengqiao diversion project at 6+600 through inverted siphon and diversion tunnel. The north main canal is 8 kilometers long, including a diameter of? 300 mm inverted rainbow tube, 740 meters long; Diversion tunnel 1 seat, length160m. Laying from the left and right banks of the surface reservoir? 150 mm cast iron pipe diversion pipe with total length of 4 150 m, and what is the diameter of the right bank? 2 100 mm inverted rainbow tubes with a total length of 900 meters.

(2) Experimental project of geotechnical geochemical background development and mineral element compensation planting.

Uplift hills are formed in the clastic rock distribution area of Permian Wujiaping Formation in the experimental area, and karst valleys and depressions are mostly formed in the carbonate rock distribution area of Permian and Triassic, which is the main area where farmland is concentrated. The farmland distribution area is flat with a relative height difference of 40-70 meters. Villages are concentrated and cultivated land is contiguous. Crops are mainly rice and wheat, and cash crops are mainly rape.

1. Geochemical background development zoning

The total amount of trace elements in the parent rock of Wujiaping Formation is high, and the average contents of beneficial components N, P, K, trace elements Se and La and ce which can promote crop growth are also high. Geological background is conducive to the growth of high-quality tea. Considering the geotechnical geochemical characteristics and topographical conditions comprehensively, suggestions on agricultural planting zoning are put forward (Figure 3- 15):

1) along the stratum distribution zone of Wujiaping Formation, tea is mainly planted. In fact, the tea planting history of this stratum distribution zone in the experimental area has been many years, and a bright tea farm has been established. The tea produced has good quality and high yield, and has become a high-quality brand in Guizhou Province.

2) Flat karst canyons and depressions are mostly formed on the surface of carbonate rock distribution zone, which is the area where farmland is concentrated at present and planned as the base for developing grain and oil production.

Figure 3- 15 Agricultural Planting Zoning Map

2. Mineral element compensation planting experiment

This experiment is mainly aimed at the carbonate rock distribution zone, and carries out the experiment of agricultural products mainly based on grain.

The experimental project of crop mineral element compensation planting was selected in Wangzhai, Qingshui Village, downstream of the outlet of underground river. Geologically, it is located in the contact zone between sandstone and mudstone of Upper Permian Wujiaping Formation (P3w) and limestone of middle Maokou Formation (P2m), and the underlying bedrock for planting experimental farmland is limestone of Maokou Formation (P2m). The available water resources in this area are giant underground rivers. After the implementation of the Jumu underground river export development demonstration project, it can provide sufficient irrigation water for the cultivated land in the demonstration area.

3. Experimental process and effect

From June 5438+ 10 to June 5438+ 10 in 2005, three main crops, rape, rice and corn, were selected for mineral element compensation planting experiments in the experimental area.

(1) yield comparison experiment

1) rape planting experiment. According to the farmers' voluntary principle, two of them (1.24 mu) were selected as the experimental group, and the adjacent 0.34 mu was used as the control group. They were planted according to the conventional planting method without spraying compensation mineral fertilizer. The experiment began at the beginning of February 2005, when the rape was branched, and ended at the time of rape harvest. Observation and comparison were made during rape growth and after harvest. March 10, the experimental group and the control group were compared. The results showed that the fertilization group had many branches, most of which had blossomed and grew well, while the control group had few branches and only a few flowers, and its growth was relatively poor (plates 4-5, 4-6, 5- 1, 5-2). After the rape was harvested in May 13, the 1000-grain weight of rape in the fertilization group and the control group was weighed, and the oil yield was compared: the 1000-grain weight of rape in the fertilization group was 2.6880g, and that in the non-fertilization group was 2.0759g, with a difference of 0.6 12 1 g; The oil yield of rape was 33.6% in the fertilization group and 25.2% in the control group (Table 3-5).

Table 3-5 Experimental Results of Rape Demonstration Planting in Demonstration Area

2) Rice planting experiment. In 2005, compensation planting experiments of spraying mineral fertilizers on 35 households with 60 mu of rice were carried out in Qingshui village, the experimental area. At the beginning of June, the experimental group sprayed mineral fertilizer within 6 days after transplanting the seedlings, and observed and compared them during the rice growth period and after harvest. By August 4th, two paddy fields were randomly selected in the experimental group and two paddy fields were randomly selected in the control group for comparative observation of rice tillering. The observation results showed that the average tillering rate of rice in the experimental group was 18.0 ~ 19.2 plants, and the tillering rate was 24. 13% ~ 58.67%, while that in the control group was 12.67. On September 22, 2005, presided over by Pingtang County Agriculture Bureau, the seed company of Pingtang County Agriculture Bureau, Tangbian Town Agricultural Development Office, village committee, villagers' group and other related units formed an acceptance team to measure the field yield of this rice planting experiment. The results showed that in 2004, the total output of rice in this 60 mu paddy field without inorganic fertilizer was 36,776 kg, and the average yield per mu in 2004 was 665,438 02.9 kg.

Table 3-6 Comparison of Tillers in Rice Demonstration Planting Experiment in Qingshui Village

In addition, in the planting experiment, corn planted in some dry land in the experimental area and tea in Guangming tea farm were sprayed, and good results were achieved.

(2) Quality contrast experiment

The crops compensated by mineral fertilizer and the crops not compensated by mineral fertilizer were sampled and tested respectively. According to the test results, the quality of the former is obviously better than that of the latter (Table 3-7).

Table 3-7 Overall Analysis Results of Agricultural Products Quality Unit:%

Benefit analysis of verb (verb abbreviation) experimental project

By 2006, the first phase of the project has been basically completed. Affected by supporting project funds, the second phase of the project failed to be implemented as scheduled.

(A) the first phase of the project benefit evaluation

1. Social welfare

1) solved the drinking water problem of more than 5000 people and 1000 large livestock in Tangbian Town, Pingtang County, ended the long-term history of water shortage and impurity of local people, and achieved the national drinking water safety goal.

2) It has alleviated the problem of drought and water shortage in more than 6,000 mu of farmland, and provided conditions for increasing grain production and promoting local poverty alleviation.

3) It has improved the enthusiasm of local farmers for scientific farming. The planting experiment of rock mineral fertilizer has improved the yield and quality of its agricultural products to varying degrees, stimulated the enthusiasm of local people for scientific farming, and achieved the expected results welcomed by the government and satisfied by farmers. We have successfully explored a road for agricultural geological science to serve agricultural production and promote agricultural economic development.

4) Improvement of local production and living conditions. The demonstration project closely combines the urgent production and living needs of the masses and the karst water resources development project, and uses the surface reservoir dam to build a traffic bridge, which improves the traffic, living and production conditions of the people on both sides of the Jumu River and provides convenience for the people on both sides.

5) Enhance people's trust in the Party and the government and enhance cohesion. The demonstration project has brought tangible benefits to the local people, played a role in developing and stabilizing the party, enhanced the people's trust in the party and the government, enhanced cohesion, and strengthened the relationship between local cadres and the masses.

6) The feasibility of geological restoration model of karst rocky desertification in rocky mountain areas is confirmed, which provides a model for geological restoration model of karst basin in karst peak cluster depression.

2. Economic benefits

1) According to the information provided by Pingtang County Water Conservancy Bureau, irrigation of 6,000 mu of farmland below the outlet of underground river can increase grain production by 900,000 kg/year (average yield increase 150 kg/year). According to the local market price of rice 1.9 yuan/kg, only one agricultural production can realize economic income 10.

2) The results of mineral fertilizer planting test in the demonstration area show that the yield of rice is increased by 50.6 kg/mu, and the yield of rape is increased by 14.7 kg/mu. According to the local rice price 1.90 yuan/kg and rapeseed 5.20 yuan/kg in 2005, the annual income per mu of cultivated land can be increased by 172.58 yuan. Therefore, it is predicted that planting mineral fertilizers on 6,000 mu of cultivated land in Kedu and Tangbian towns in the demonstration area will increase the economic benefit by 6,543.8+0.355 million yuan per year.

3. Benefit Evaluation of Phase I Project

The first phase of the project not only achieved good social benefits, but also achieved good economic benefits. The actual total investment of the first-phase demonstration project of underground river development is 2.37 million yuan (including 6.5438+700 million yuan for geological survey and 670,000 yuan for Pingtang County). According to the analysis of geoscience model test results, the first phase of the project can increase the annual income of the irrigation area by 2,802,900 yuan, and the economic analysis shows that the project has good benefits.

(II) Benefit Forecast of Phase II Project

1. Prediction and analysis of social benefits

1) Solve the drinking water problem of more than 6000 people and 10000 large livestock in Tangbian Town and Kedu Town of Pingtang County, and realize the national drinking water safety goal.

2) Solve the problem of irrigation water for 12000 mu of farmland in the river basin and downstream drought and water shortage areas.

3) Eliminate the karst floods in the west, such as overflow dam and mixed valley, and make the low-lying land combine with cultivated land to be cultivated again through land consolidation, so as to make full use of the precious land resources in karst areas.

4) Harnessing the karst flood of the dam and mixed valley, combining land resources development with poverty alleviation and rocky desertification control, can realize the ecological resettlement of more than10.5 million people (the current average population density is 78 people /km2) in the rocky desertification area in the river basin and downstream, and create basic conditions for the survival and poverty alleviation of immigrants.

5) In the rocky desertification area of19.28km2 after emigration, closing hillsides to facilitate afforestation, planting trees and returning farmland to forests can be implemented to restore the rocky desertification ecological environment.

2. Economic benefit analysis

According to the actual test results, the grain yield can be increased by 607,000 kg/year (calculated as an increase of 50.6 kg/(mu/year)) after the irrigation is guaranteed and the mineral fertilizer compensation is implemented in the farmland below the underground river outlet. The yield of rapeseed can be increased by 176000 kg (according to the experimental results, the yield can be increased by 14.7 kg/(mu). The total grain output of the whole region has increased by 654.38+507 kg/year, and that of rapeseed has increased by 365.438+0.1100,000 kg. According to the current local market price of grain and oil (rice 1.9 yuan/kg, rapeseed 5.2 yuan/kg), the economic income of agricultural production alone is 4,480,500 yuan/year, not including other benefits brought about by industrial restructuring driven by underground river development.

The pilot project of rocky desertification control in Jumu underground river basin has obvious comprehensive benefits, which is of great significance to local social and economic development, improvement of ecological environment and promotion of local people to get rid of poverty and become rich. An ecological environment control approach based on geoscience theory is explored to prevent the occurrence and development of rocky desertification in karst peak-cluster depression with serious soil erosion.