(1. Shandong Institute of Geology and Mineral Resources, Jinan 250014; 2. Jinan University, Jinan 250002)
About the author: Shi Baoyu, 1982, graduated from the Hydraulic Department of Changchun Institute of Geology. He presided over the compilation of environmental hydrogeology map of Shandong province, investigation and evaluation of geological disasters in Shandong province and many other water conservancy environmental geology investigations and studies.
Building an ecological province is an important strategic measure for Shandong Province to implement the strategy of sustainable development. Based on the environmental geological problems in the process of economic construction and social development in Shandong Province, this paper discusses the occurrence, development and evolution of geological environmental problems and their relationship with the construction of ecological province. It is of practical significance for the construction of ecological province and the sustainable development of economy to put forward measures and suggestions for the improvement and restoration of geological environment from a macro perspective.
Keywords: environmental geology; Ecological province; Renovation and restoration of geological environment; Shandong (province)
Shandong Province is located in the eastern coast of China and is rich in natural resources. With the rapid development of economy and society, while human beings are pursuing the maximization of resource potential economic benefits, the geological environment problems brought by it are becoming more and more serious, which directly restricts the sustainable development of Shandong economy. Therefore, building an ecological province is an important strategic measure to implement the strategy of sustainable development and realize the construction of a "big and strong, rich and beautiful" socialist new Shandong. "Eco-province" requires the coordinated development of economy, society and ecological environment, and requires us to use Scientific Outlook on Development to achieve the goal of sustainable development in all fields. The management and protection of geological environment is an important link in the construction of ecological province.
The geological environment in Shandong Province is fragile. With the rapid development of economy, the impact and destruction of human activities on the geological environment is becoming more and more serious, which leads to the decline of the quality and capacity of the geological environment and directly threatens the sustainable development of the economy.
1 Geological background and development law of geological environment problems
The mountainous terrain in the middle of Shandong Province is prominent, the eastern part is gentle and hilly, and the northern and western parts are flat, which constitutes the terrain with low mountains and hills as the skeleton and plain basins criss-crossing. Shandong's landforms can be divided into hills in eastern Shandong, hills in central Shandong, hills in southern Shandong and plains in northwest Shandong. From the perspective of stratigraphic development, Yishu fault, Qihe-Guangrao fault and Liaocheng-Lankao fault can be divided into three geological structural units: eastern Shandong, central and southern Shandong and northwestern Shandong. Guyu, Archaean, Mesozoic and Cenozoic developed in eastern Shandong, and a set of metamorphic rock series dominated. The surface of northwest Shandong plain is Quaternary, mainly alluvial loose deposits, and the underlying strata are Paleozoic, Mesozoic and Cenozoic. South-central Shandong Province is the most complete area of stratigraphic development in Shandong Province, with a typical North China-type stratigraphic system.
The unique geological conditions lead to complex geological background, rich mineral resources, many types, large reserves and wide distribution in Shandong Province. There are still many geological and environmental problems in Shandong Province. From the cause of formation, the geological environmental problems in Shandong Province can be roughly divided into three categories: ① A series of environmental geological problems caused by mining, such as ground collapse, mountain cracking, collapse, landslide, debris flow, mine water inrush, gas explosion, soil erosion, soil and water pollution, slag tailings accumulation and land occupation and regional water balance destruction; (2) Problems such as seawater intrusion, land subsidence, karst collapse, continuous decline of groundwater level and groundwater pollution caused by unreasonable development and utilization of groundwater resources; ③ Collapse, landslide, debris flow and soil erosion caused by engineering activities.
The development and distribution of geological environment problems in Shandong Province have its regularity: ① The hilly areas in central and southern Shandong Province are relatively steep, with large topographic differences and rich mineral resources. The main geological environment problems are mine environment problems, karst collapse, soil erosion and collapse, landslides and debris flows; (2) Eastern Shandong is surrounded by the sea on three sides, with low hills and rich gold deposits, and its geological environment problems are mainly seawater intrusion, gold mine environment problems and soil erosion; (3) Northwest Shandong is mostly alluvial plain of the Yellow River with flat terrain, and its geological environment problems are mainly land subsidence, unbalanced over-exploitation of deep groundwater and the formation of permanent groundwater funnel.
Man-made geological processes have destroyed the balance of nature, resulting in many adverse environmental geological problems and geological disasters. The occurrence and development of these problems have seriously restricted the grand goal of building an ecological province (see figure 1).
Figure 1 Relationship between Main Geological Environment Problems and Eco-province Construction in Shandong Province
2. The main geological and environmental problems that threaten the construction of ecological province
2. 1 Mining destroys the geological environment system of the mining area, and the mine environment problem is serious.
Shandong Province is a province with relatively complete mineral species in China. By the end of 2006, there were 0/50 kinds of minerals 1 1 species in the whole province, including 45 kinds of metal minerals, 90 kinds of non-metal minerals and 4 kinds of water and gas minerals. Mining activities such as underground mining, slope excavation, waste residue and tailings discharge induce a series of environmental geological problems, such as ground collapse, karst collapse, mountain cracking, collapse, landslide, debris flow, tunnel water inrush, gas explosion, soil erosion, water and soil pollution, tailings dam breach and regional water balance destruction, which pose a threat to mine development and construction. With the large-scale development and utilization of mineral resources, the material circulation and energy flow mode of mine ecosystem have changed greatly, causing serious ecological damage and environmental pollution.
According to the survey, by the end of 200 1, the land occupied by various mining enterprises in Shandong province was * * * * 8228.16km2, accounting for 5.3% of the total land area of the province. The total annual output of mine tailings and solid waste is 52,708,200 tons, and its area is increasing at an annual rate of about 4km2. The total annual output of mine water and mineral processing wastewater is 936 million cubic meters, and the annual discharge reaches 507 million cubic meters. Due to mine geological disasters such as mine water inrush and goaf collapse, 98 people were killed or injured, and the economic loss of property was11990,000 yuan.
In the development of mineral resources, coal mines, iron mines, gypsum mines and gold mines are the main causes of ground subsidence, especially coal mines. The area of coal mining subsidence area in Shandong Province is 332.23km2, of which the area of coal mining subsidence area is 327.76km2, accounting for more than 98% of the total subsidence area. The perennial water accumulation area of the subsidence area is 48.2km2, and the depth of ground subsidence is generally 2.5~7.5m, and the deepest part can reach 9.2m Due to the subsidence of mined-out area, the surface vegetation, soil and stratum structure are destroyed, and the natural ecological environment is seriously deteriorated. The area of unproductive cultivated land abandoned due to excessive topographic relief and perennial water accumulation on the surface exceeds 36 square kilometers. Mining subsidence has also caused the destruction of public facilities and surface water resources.
The exploitation of building materials and other minerals has destroyed the natural environment and geological landscape to varying degrees, and also aggravated soil erosion. Most of these mines are open-pit mining. Long-term open-pit quarrying, sand mining and earth borrowing have formed many quarrying (sand and soil) pits, excavation faces, waste slag and rolling stone belts, which have seriously damaged the geological landscape, especially along the traffic lines and coastal areas, and the surface damage caused by open-pit mining is more prominent. In addition, there are more or less hidden dangers of rock mass instability in its slopes, especially in flood season or under the influence of vibration, which are prone to geological disasters such as collapse, landslide and debris flow, and casualties caused by such disasters occur from time to time in Shandong Province. In addition, in the process of exploiting oil, brine and other metallic and nonmetallic minerals, the surrounding environment has also been affected to varying degrees.
2.2 Sea (salty) water intrusion harms the ecological environment, groundwater resources and agricultural ecology in coastal areas.
Sea (salty) water intrusion in Shandong Province began in the mid-1970s. In recent 30 years, with the increase of groundwater exploitation, the scale of sea (salty) water intrusion has been expanding. At present, from Guangrao to Longkou, there are different degrees of sea (salty) water intrusion throughout the south bank of Laizhou Bay. In the estuaries of Qingdao, Weihai, Yantai and other places, there have also been seawater intrusions of different scales.
2.2. 1 salt water intrusion
Salt water intrusion occurred in Guangrao-Shouguang-Hanting-Changyi-Pingdu coastal low plain. The terrain of this section is flat, and the beach width is 10 ~ 18 km, and the elevation is below 5m, which is mostly beach saline-alkali land. Groundwater runoff is slow, mostly salt water or brine. South of salt water is the piedmont alluvial plain, with gentle groundwater runoff and strong water alternation, and the water quality is low mineralized fresh water. Under natural conditions, groundwater flows from south to north, and part of it discharges supplementary salt water. In recent 20 years, due to the exploitation of underground fresh water in this area, the water level in the fresh water area has dropped obviously, and the water level near the interface between salt and fresh water is lower than that of salt water, resulting in reverse recharge and salt water intrusion. At present, the salt water intrusion area in Shandong Province has reached1869.6km2.
saline water intrusion
Seawater intrusion mainly occurs in the accumulation plain on the south bank of Laizhou Bay in Laizhou-Zhaoyuan-Longkou area. The area is narrow and banded, with a width of 3 ~ 5 km. Under natural conditions, groundwater is discharged in the direction of seawater. Over-exploitation of groundwater leads to groundwater level lower than seawater level, and seawater supplies inland, leading to seawater intrusion. The estuaries of Yantai, Weihai, Qingdao and other cities are the main local water supply sources. Due to over-exploitation of groundwater, the groundwater level along the banks of the river has dropped significantly, and seawater intrusion has also formed. At present, the seawater intrusion area in Shandong Province has reached 587.64km2.
The intrusion of seawater (salty water) makes the groundwater salinized, the soil salinized, and the vegetation on the surface is sparse. Only a few salt-tolerant plants can grow in serious areas, which destroys the original good agricultural ecology. After the salinization of groundwater, the original water supply source of the enterprise was destroyed and forced to close down and move, resulting in serious losses; Jiaodong area is one of the most water-deficient areas in Shandong Province, and seawater intrusion destroys scarce groundwater resources, which greatly restricts regional economic development.
2.3 Soil erosion leads to poor land and fragile mountain ecosystem.
Shandong province, which straddles the Yellow River, Huaihe River and the sea, has a fragile ecological environment and is one of the provinces with serious soil erosion in China. The results of the second national remote sensing survey show that the area of soil erosion in Shandong Province is 6.35× 104km2, accounting for 40.5% of the total land area of the province. Among them, the area of soil erosion in hilly area is 5.2× 104km2, and that in plain sand-blown area is1.15×104km2. Among them, the soil erosion area is light 1.98× 104km2, moderate 2.37× 104km2, strength 1.38× 104km2, and extreme strength is 0.65×1km2. Soil erosion not only destroys farmland, reduces land fertility and crop yield, but also silts up water conservancy facilities such as reservoirs, bridges and culverts. According to relevant data, due to soil erosion, the province washes away 2.8× 108t of soil every year, with an erosion modulus of1787t/(km2 a), an average annual erosion depth of 1mm, and nutrient loss is equivalent to 4 19t standard chemical fertilizer. Considering the self-fertilization ability of soil and the uncultivated mountainous area with bare bedrock, the annual economic loss caused by soil erosion is equivalent to. Due to soil erosion, the average annual sedimentation of major rivers is1.19×104m3/km2, and that of reservoirs, lakes and ponds is 6.9× 107m3.
Soil erosion not only loses soil fertility, silts up rivers, lakes, ponds and dams, but also makes the vegetation in mountainous areas lose the soil on which to live and worsen the ecological environment. Serious soil erosion has become an important factor restricting the sustainable development of Shandong economy and society.
2.4 Land subsidence damages the urban water supply and drainage system and endangers the sustained, stable and healthy development of the national economy.
Land subsidence mainly occurs in the northwest plain of Shandong Province, mainly due to man-made over-exploitation of groundwater, resulting in water loss and compaction of aquifers and adjacent weak aquifers. The cities with obvious land subsidence in Shandong Province are Dezhou, Jining and Heze (table 1). Land subsidence will lead to a series of hazards, such as the destruction of buildings, the reduction of port and wharf functions, the reduction of net capacity of bridges and culverts, the impact on water conservancy traffic, and poor urban drainage.
Table 1 Basic information of main land subsidence areas in Shandong Province
2.5 Karst collapse threatens the safety of residents' lives and property, and affects transportation and industrial and agricultural production.
Karst collapse is caused by changes in the dynamic conditions of groundwater and the mechanical relationship between soil and groundwater during human engineering activities, especially when extracting karst groundwater. The ground collapse caused by the exploitation of karst water mainly occurs in Tai 'an, Zaozhuang, Laiwu, Linyi and other places.
Karst collapse will lead to many problems such as residents' damage, casualties, road damage, mine shutdown, water pollution and so on.
2.6 Unreasonable exploitation of groundwater resources caused a significant drop in groundwater level, forming a permanent over-exploitation funnel.
There are many over-exploitation funnels for groundwater in Shandong Province (see Table 2). The formation and development of groundwater over-exploitation funnel is mainly due to long-term unreasonable exploitation of groundwater, which destroys the dynamic balance between groundwater exploitation and recharge in mining areas, leads to the continuous decline of groundwater level and the discharge of aquifer storage, thus forming an over-exploitation drainage funnel. Land subsidence is mostly caused by over-exploitation of deep groundwater.
Table 2 Statistics on the basic situation of main groundwater over-exploitation funnels in Shandong Province
Other geological and environmental problems are also prominent, such as soil salinization, earthquake and sand liquefaction, siltation and tailing of the Yellow River, the harm of expansive soil and collapsible loess, endemic diseases and so on. If we don't understand these problems clearly and can't take effective measures to contain them, it will directly threaten the grand cause of building an ecological province in Shandong Province.
3. Renovation and restoration of geological environment
The use of geological environment by human beings should be limited, everything must conform to objective laws, and activities must be carried out within the limits allowed by the capacity of geological environment. Due to the improper protection and utilization of geological environment in economic construction, a large number of geological environment problems have arisen, which have caused huge economic losses and social impacts and restricted the healthy development of the economy. It is very important and urgent to strengthen the research, management and protection of geological environment.
3. 1 Establish and improve relevant laws and regulations, formulate policies and strengthen management.
The establishment of relevant laws and regulations and the implementation of management policies conducive to the geological environment are the guarantee for the management and protection of the geological environment. After years of efforts, Shandong Province has established a set of laws and regulations on geological environment management, but it is still not perfect. The next step should be to increase the intensity of construction and gradually improve it. On this basis, we should strengthen propaganda and management, and constantly improve the geological environment awareness of government leaders at all levels and the masses, so as to raise it to the height of the legal system and get attention. Further improve the internal supervision system of governments at all levels, strengthen the supervision of leading cadres at all levels on the implementation of laws, regulations and government rules on environmental resources, implement the accountability system, and ensure the implementation of laws, regulations and plans.
3. 1. 1 Strengthen leadership, improve institutions and strengthen management.
Protecting and improving the geological environment is a social welfare undertaking and one of the main responsibilities of governments at all levels and relevant departments. It is necessary to clarify responsibilities, conscientiously implement the central government's basic principles and policies on environmental protection, fully perform responsibilities, and earnestly do a good job in management and protection.
3. 1.2 Strengthen the construction of the legal system and adhere to administration according to law.
Because geological environmental protection involves a wide range, the situation is complex, the task is arduous and the responsibility is great, we must act in strict accordance with relevant laws and regulations, adhere to administration according to law, and conscientiously implement the Regulations on Geological Environmental Protection in Shandong Province. According to the reality of Shandong Province, improve the detailed rules for the implementation of various laws and regulations, and promote the construction of local laws and regulations.
3. 1.3 Incorporate geological environment protection and improvement planning into national economic and social development planning.
Governments at all levels should incorporate geological environment protection and improvement plans when formulating economic and social development plans or plans.
3. 1.4 Increase funding.
According to the principle of "who develops, who protects", the major national projects are mainly invested by the central government, and the key geological environment protection and remediation funds in the province are mainly invested by the provincial finance, supplemented by the municipal finance; The funds for the protection and renovation of construction areas under the jurisdiction of various industries and enterprises shall be borne by all departments, and enterprises and individuals shall be encouraged to invest through multiple channels to do a good job in the protection and renovation of geological environment with economic leverage.
3.2 Strengthen scientific research to provide decision-making basis for comprehensive management and restoration of eco-geological environment.
Various geological processes and processes do not exist in isolation, they are closely related. Man-made geological processes have destroyed the balance of nature, resulting in many adverse environmental geological problems and geological disasters.
Geological environment should mainly study its quality, capacity and economic carrying capacity. Geological environmental capacity refers to the maximum potential that can withstand the development of human society, economy and engineering in a specific geological space. It can be measured by the amount of geological resources and the ability to accept human waste. The capacity of geological environment is limited.
3.2. 1 Investigation and study is the premise of environmental remediation.
The prevention and control of geological environmental problems is based on the analysis of genetic mechanism, which is based on geological exploration to avoid the mistakes of prevention and control projects. A correct understanding of geological environmental problems and their occurrence mechanism is the most important prerequisite for geological environmental governance.
3.2.2 Pay attention to the application of new technologies.
At present, CAD, GIS and three-dimensional animation technology have been introduced into the field of geological investigation and research, with the goal of establishing an intelligent aided design system based on geological genetic mechanism for early warning and prediction, which has been a successful precedent at home and abroad.
3.3 Strengthen investigation and study, restrain human activities, harness the whole landscape and protect the geological environment.
3.3. 1 Strengthen scientific research, scientific management and improve mine environment.
The geological environment problems in Shandong mines are serious, mainly because there are too many problems left over from history and new problems appear constantly. At present, enterprises simply cannot undertake the heavy task of ecological environment management, resulting in a vicious circle of resources and environment, which seriously restricts the economic development of mines, and some mines have irreversible consequences.
Accelerate the comprehensive improvement and reclamation of ground subsidence in old mining areas and gradually solve the problem of ground subsidence in old mining areas. According to the principle of "whoever mines and reclaims", the ground subsidence in the new mining area should be rectified and reclaimed in time. Strengthen the restoration and management of open pit on both sides of famous scenic spots and main traffic trunk lines. Restore the destroyed mountain ecological environment around cities, railways, highways, national highways and provincial highways.
3.3.2 Further investigation and evaluation of groundwater resources, rational development and utilization of groundwater.
Groundwater environment is an important part of geological environment, including groundwater itself and its medium environment. Generally speaking, Shandong Province is seriously short of water resources. There are the following outstanding problems in groundwater resources: ① the degree of investigation and research is not enough. The comprehensive investigation and evaluation of groundwater was completed in the 1980s, and it has been more than 20 years. Many environmental conditions have changed, especially surface water and meteorological conditions, so a new round of investigation and evaluation of groundwater resources potential is needed. ② Insufficient research on groundwater environmental protection. Most areas of Shandong province have not been divided into groundwater protection areas. According to the sensitivity of geological environment conditions and the water supply function of groundwater resources, the first and second protected areas and quasi-protected areas are divided as required, and protection measures are implemented as soon as possible. ③ The layout of development and utilization is not reasonable enough. Unreasonable urban layout is the main factor of unreasonable water use layout. Jiaodong area has developed economy, many cities and large water consumption, but Jiaodong is a relatively water-deficient area in Shandong Province. The water quality and abundance of shallow groundwater in plain area are poor, and the recharge source of deep groundwater is insufficient, which limits the large-scale development and utilization. Cities in piedmont plain are concentrated, most of the groundwater resources are over-exploited, and groundwater pollution is serious. ④ The investigation and test of artificial storage of groundwater are insufficient. Hydrogeological conditions, aquifer water storage capacity, types and locations of water storage projects, reasonable buried depth of groundwater and its impact on ecological environment have not been thoroughly studied. ⑤ Most areas have certain development and utilization potential. Groundwater resources are renewable, and groundwater in most mountainous areas circulates rapidly and alternately, so it is also a waste not to develop and utilize the potential.
3.3.3 Scientifically standardize engineering activities to prevent collapse, landslide and debris flow disasters.
Man-made geological processes are directly involved in the transformation of lithosphere and the destruction and reconstruction of landforms, such as blasting, slope cutting, excavation, slag abandonment and filling in engineering construction. These activities may lead to slope deformation, rock loosening and collapse, landslides and debris flows.
Earthquake, rainstorm and human activities are three important factors that induce collapse, landslide and debris flow disasters. At present, human beings cannot control the first two, but they can regulate and restrain their own economic activities. Therefore, in engineering activities, we must fully understand and respect the laws of nature with a scientific attitude, so as to realize the harmonious coexistence of human beings and social and natural. Therefore, before carrying out various engineering activities, we must seriously investigate and study the geological environment conditions and evaluate the adaptability of related engineering construction. We must strictly standardize the process of survey, design and construction, so as to standardize and rationalize the engineering construction design.
3.3.4 Strengthen the comprehensive management of small watersheds to prevent and control soil erosion.
Soil erosion was originally a natural geological process, and its disasters were mainly caused by man-made destruction of vegetation and indiscriminate reclamation and deforestation, which aggravated this process. Therefore, it is necessary to strengthen the comprehensive management of small watersheds, plant trees, conserve water sources and improve the ecological environment in mountainous areas; Man-made soil erosion has been effectively controlled, and a soil erosion prevention and control supervision system and a soil erosion monitoring network have been gradually established; Realize the coordinated development of soil and water conservation and development and construction, prevent new man-made soil erosion, and ensure the obvious improvement of ecological environment quality.
3.3.5 According to local conditions, the geological environment problems shall be divided into districts and focused on remediation.
According to the existing environmental geological problems in Shandong Province, it is necessary to highlight the key points and carry out targeted remediation: ① The Yellow River Delta, focusing on remediation of land subsidence caused by groundwater exploitation and oil exploitation. ② The prevention and control of land subsidence, salt water intrusion and goaf collapse are the key points in Lubei Plain; Dezhou focuses on preventing and controlling land subsidence: Ningjin, Boxing, Guangrao, Shouguang and Changyi mainly focus on land subsidence and salt water intrusion. Dong 'e, Yanggu, Qihe, chiping, Jiyang and other places contain coal resources that have not been developed on a large scale, so pay attention to prevent potential goaf collapse and ground collapse. (3) In Heze, Jining, Yanzhou, Wenshang and other places in the southwest of Shandong Province, goaf collapse and land subsidence are the main reasons. (4) The prevention and control of landslides and landslides should be focused on the middle and low mountains and hills in central and southern Shandong, and the goaf collapse and karst collapse caused by the exploitation of mineral resources and over-exploitation of karst water should be focused on Jinan, Zibo, Weifang, Tai 'an, Jining, Zaozhuang and Linyi. ⑤ There are many problems of goaf collapse, collapse, debris flow and seawater intrusion in the low mountains and hills in eastern Shandong, especially in coastal areas. Laizhou, Zhaoyuan, Longkou, Qixia and Laoshan, the prevention and control focus is on goaf collapse, collapse, debris flow and seawater intrusion, and the prevention and control focus is on the coastal areas of Weihai, Rizhao, Yantai and Qingdao; Linshu, Zhucheng and Jiaolai basins focus on the prevention and control of ground fissures.
4 conclusion
Geological environment protection is an important link in the construction of ecological province. Leaders at all levels should clearly understand the constraints of the deterioration of geological environment on the social economy of Shandong Province. Adhere to the principle of "protection in development and development in protection", and strengthen investigation and research, unified planning and scientific management in view of the different geological environment problems existing in various parts of Shandong Province. Protecting the geological environment, the merit lies in the present and the benefit lies in the future!
refer to
Jiang Jianjun. 2004. Geological environment and urban sustainable development. Journal of China Institute of Environmental Management, 04.29.
Xu, Shi Baoyu, Cheng. 2002. Discussion on main eco-environmental geological problems and investigation and evaluation methods in Shandong Province. Geology of Shandong, 12.