Discussion on characteristics, existing problems and prevention countermeasures of geological disasters in Guizhou Province

(Guizhou Geological Environment Monitoring Station, Guiyang, 550000)

This paper analyzes the characteristics of the occurrence and development of geological disasters in Guizhou Province, summarizes the demonstration and control effects of seven typical geological disasters in Guizhou Province, puts forward the main problems in the prevention and control of geological disasters in view of the current reality of geological disasters in Guizhou Province, and finally discusses the countermeasures and suggestions for further prevention and control of geological disasters in Guizhou Province according to the principles and policies of the Ministry of Land and Resources and Guizhou Province.

Keywords: development characteristics of geological disasters, prevention and control countermeasures, Guizhou

All living things on the earth depend on the geological environment and are the most basic habitat for human beings. "Protecting the earth means protecting our living space" has become people's understanding and call. With the intensification of human activities and the development of economy and society, geological disasters such as landslides, collapses and mudslides have become the main problems that seriously threaten people's lives and property. According to the principles of "people-oriented", "prevention first, combining prevention with control, overall planning and comprehensive management", Guizhou has made important progress in the field of geological disaster prevention and control, especially the land and resources department has actively performed its duties and selected several typical geological disasters for demonstration and management, which has played an important role in functional departments and produced good social and economic effects. However, due to the special natural geographical and geological conditions and relatively backward economic situation in Guizhou Province, heavy rainfall and various engineering activities in flood season are still the main factors leading to frequent geological disasters, and the situation of decentralized passive emergency response has not been fundamentally changed. It has become an important subject for geological environmental protection workers to analyze the existing problems and explore the prevention countermeasures.

Characteristics of Geological Disasters in Guizhou 1

1. 1 Special natural geographical and geological conditions and human activities make geological disasters frequent and complete.

Guizhou province is located in the center of the largest contiguous karst mountain area in southwest China and abroad, mostly in valleys, with the characteristics of high mountains, steep slopes and deep valleys. Due to soil erosion, the rocky desertification area has reached 32,500 km2, accounting for 18.45% of the province's land area. Abundant rainfall, sparse vegetation, soft and hard strata exposed, and few people and land make the geological ecological environment in this province very fragile, and various geological disasters occur frequently, and 6 kinds of common geological disasters have been found. According to the results of geological disaster investigation and zoning in 27 counties and cities completed by 2002, the province has mastered more than 6.5438+0.2 million hidden danger points of geological disasters, delineated more than 4,400 important hidden danger points, and preliminarily counted more than 380,000 threatened people. According to incomplete statistics, since 1998, there have been more than 50 geological disasters 1 150 in the whole province (including 65,438 major disasters with more than 65,438 deaths or direct economic losses of more than 5 million yuan), resulting in 29 deaths1person.

The deep slope topography of 1.2 valley determines that landslides, collapses and mudslides are the main geological disasters.

Because the territory is located in the slope zone of the transition from Yunnan-Guizhou Plateau to Guangxi hilly plain, the main geological disasters are landslides, collapses and mudslides. Through the statistical analysis of 345 geological disasters since 1993, it is found that landslides, collapses and mudslides account for 70%, 1 1% and 10% respectively. In recent years, the proportion of landslides and mudslides has been rising. Through the statistical analysis of more than 40 major geological disasters in recent five years13, landslides still dominate, accounting for about 60%, while landslides account for 20% and mudslides account for 13%. These three disasters often occur together, expanding the scope of harm and influence, and causing great losses to people's lives, property and economic construction. For example, the landslides in Dafang County in the upper reaches of Wujiang River, Sinan County and Yanhe County in the middle reaches, Shiqian County landslide and debris flow, Yankou County landslide, Shanshan Primary School landslide, the second landslide in the county, and Datong City landslide in Chishui City are all very serious and the losses are particularly huge.

1.3 The climate features of distinct seasons and concentrated rainfall make the heavy rainfall in the main flood season the main inducing factor of geological disasters.

The climate in Guizhou Province is mild and rainy. In the rainy season, people often say that it will clear up in three days. Generally, April-August is the rainy season, but the main flood season is June-July, and the geological disasters caused by heavy rain account for about 70% of the total. Major and extraordinarily serious geological disasters are often concentrated in this period. 1From June 27th to 30th, 999, there were heavy rainstorms in northern, central and eastern Guizhou, and 22 geological disasters occurred in 1 1 counties and cities. On June 6-8, 2000, there were heavy rains in northern and southern Guizhou, and 8 counties and cities induced geological disasters 10, accounting for 40% of the total disasters in the same period for two consecutive years. On June 25th, 2003, there was a four-hour rainstorm in Xishui County, northern Guizhou Province, which affected the county seat and 24 townships, triggered flash floods and mudslides, and washed away power plants, highways, dams and houses, resulting in five deaths and 20 missing.

1.4 The population is large and the land is small, the economy is backward, and the engineering activities are intensified, which has gradually become the man-made inducement of geological disasters.

The level of urbanization and rural urbanization in Guizhou Province is relatively low, with a large population and insufficient cultivated land per capita 1 mu. Deforestation, quarrying, sand mining, coal mining and other activities that destroy the natural ecological environment are another important factor that causes the vicious circle of economy and frequent geological disasters. According to incomplete statistics, geological disasters caused by unreasonable human engineering activities accounted for 15% ~ 35% of the total geological disasters in that year, but this proportion is still increasing year by year. 200 1 year is a dry year in the whole province. There were still casualties in geological disasters 19, with 63 deaths, including 5 related to human engineering activities and 39 deaths, accounting for 62%. Although 1 1 people died of natural factors, only 165438 people died. It can be seen that geological disasters induced by human activities can not be ignored. We have noticed that many geological disasters in reality can more or less see the shadow of human activities. 1September, 1996 18, Yankou landslide occurred in Yinjiang county, which was induced by high and steep free surface formed by quarrying all the year round. Because it is located in the upper reaches of the Yinjiang River, 1800 m3 of rock and soil slipped into the Yinjiang River to form a dammed lake, which flooded 4 villages 1 town 1830 households and 3,000 mu of farmland. If the dammed lake breaks, it will threaten the life safety of 54,000 people in the county and downstream of the river, and it is estimated that the possible economic loss will be about 2.4 billion yuan.

2. Typical geological disaster demonstration control effect

2. 1 landslide control in Yan Baihu, Sinan County

Landslide is located in the slope area along the Wujiang River. Due to the frequent change of water level in Wujiang River and the influence of heavy rainfall, it began to creep and deform in June 1996, and it was a medium accumulation landslide. The longitudinal length of landslide is 104m, the front width is 172m, the average thickness is 10m, and the sliding body is about 200,000m3. The sliding horizon is mudstone of Xiushan Formation of Middle Silurian. Adopting the scheme of anti-slide pile+slope protection+drainage interception, the state and local governments invested 4 17000 yuan (including 654380+05000 yuan for investigation), which was treated in two phases in 2000 and 2002, making the waterworks and more than 20 million yuan 10 enterprises and institutions safe. The first phase of the project was rated as excellent by China Geological Survey.

2.2 Yankou landslide residue and dangerous rock mass treatment in Yinjiang County

The landslide is located at 46.5438+0 km upstream of Yinjiang River. Due to years of quarrying and continuous heavy rain, 2.222 million cubic meters of bedrock cutting landslide has been formed. Among them,1.8000 m3 of rock and soil slipped into the river to form a rockfill dam, with a height of 5 1.4m, a longitudinal length of 420m, backwater 10km, a water depth of 10m, and a storage capacity of the rock plug reservoir of 62.5 million m3. On the sliding bed with a longitudinal length of 434 meters and a height difference of 1.55 meters, 422,000 cubic meters of residue was accumulated. There are 24,654,38+0,000m3 dangerous rocks left on the steep cliff on the right side wall of the sliding bed, which is 80 ~ 1.40m higher than the sliding bed. The sliding body is composed of limestone of Yulongshan Formation of Lower Triassic, the sliding layer is limestone of Changxing Formation of Upper Permian, and the sliding zone is shale of Yelang Formation of Lower Triassic, with a thickness of 8 ~ 10m. The water conservancy and flood control department adopts permanent diversion tunnels on both sides of the dam to reinforce the dam, and the land department adopts blasting to remove dangerous rock mass+residual anti-slide piles and drainage control measures, which cooperate with each other and achieve extremely obvious results. Not only did it avoid a catastrophe, but the management of the ruins also became a tourist attraction for the people of Yinjiang. A total of 3.4 million yuan was spent on the blasting of dangerous rock mass on the slope and the secondary support and drainage project of residual body, which was invested by the state and local governments.

2.3 Datong Landslide Treatment in Chishui City

Datong Town, Chishui City, located on the bank slope of Datong River, a tributary of Chishui River, is one of the famous ancient towns in Guizhou Province. 1998 due to the landslide caused by the heavy rainfall on June 24th, the provincial highway from Chishui to Xuyong in Sichuan Province was blocked, 62 houses were destroyed, 484 people were homeless in 2 1 household, 1 water plant and beverage factory were destroyed, and lifeline projects such as water, electricity and communication were destroyed, resulting in direct economic losses of more than 4 million yuan. The landslide is divided into three layers: shallow, medium and deep, with a total volume of 6.5438+0.38 million m3, and the basement is middle and lower Jurassic sandstone. From 1998 to 10 ~ 12, the local self-raised fund is 200,000 yuan to carry out retaining wall treatment project for shallow landslide, and from May to 1999, the anti-slide pile+retaining wall+drainage+biological treatment project is carried out for middle landslide, with local investment and state subsidy, with an investment of 3.74 million yuan. The treatment of deep landslide has restrained the further expansion of the disaster, exempted the safety hazards of large national enterprises such as Chishui City, Chitianhua Factory and Huayi Paper Mill, which are 8 kilometers downstream, and avoided economic losses of more than 654.38+04 billion yuan.

2.4 Shiqian County Urban Landslide Control

It consists of two parts: Dongmenpo landslide group and Chengnan hot spring landslide. Dongmenpo, facing the urban area, consists of five sliding bodies, with a width of 540m, a length of 250m, a thickness of 4.8 ~ 10.5 m and a total volume of1.2000 m3. The sliding layer is mudstone of Silurian Xiushan Formation. Chengnan Hot Spring is a provincial-level scenic spot. The landslide is 280 meters wide, 170 meters long and 6 ~ 12 meters thick, with a scale of over 320,000 cubic meters. Dangers began to appear in the early 1990s, destroying the county people's hospital, county party school, cigarette factory, tea factory and other buildings. The disaster situation further expanded in July, 1996, which directly threatened the property safety of the county party committee, county government, ethnic middle schools and other 6 1 enterprises and institutions 6 16 1 households 5,276 people. The Ministry invested 700,000 yuan for investigation, and adopted the scheme of anti-slide pile+retaining wall+water interception and drainage for comprehensive treatment by stages, with a total cost of 9.97 million yuan. From April 2000 to June 2006, 5438+0, the provincial, municipal and county governments invested 1.34 million yuan to implement the first-phase project management, which effectively suppressed the landslide deformation in the back mountain of the county Committee.

2.5 Chaoyang Collapse and Ground Fissure Treatment in Song He Township, Panxian County

Due to long-term coal mining, the mudstone of Feixianguan Formation of Lower Triassic in 1995 overlying strata began to appear mountain cracks, and the ground cracks increased in the rainy season in 2000, and obviously increased and widened in May of 200 1 year, with large-scale collapse in three places, and the residual dangerous rock mass reached 70,000 ~10m3, making 32 households/kloc-0. Once the dangerous rock mass collapses, it may form a landslide, which will turn into a mudslide, threatening the lives and property of more than 300 people in 80 households downstream. In 2002, the Ministry invested 300,000 yuan to demolish dangerous rocks by blasting. However, comprehensive management is still needed to eliminate all hidden dangers.

2.6 landslide control of Shanshan Primary School in Yinjiang County

In May of 200 1 year, affected by rainfall, two adjacent landslides occurred in this primary school, with a length of 42 ~ 50m, a width of 38 ~ 85m, a thickness of 2.23m and a volume of 3,500 ~1000 m3, which are shallow loose accumulation landslides and the strata are Silurian Xiushan Formation mudstone. It directly threatens the life and property safety of 699 people in the school and border residents. After taking anti-slide pile+retaining wall+drainage control measures, from 200/kloc-0 to 2002, the Ministry invested 600,000 yuan to eradicate hidden dangers.

2.7 Treatment of No.2 Landslide of Lipo Landslide Group in Communications Village, Longxing Town, Xishui County

1July, 1999, due to heavy rainfall, a landslide group consisting of four individual landslides occurred in Jiaocun, of which the largest landslide was No.2, with a width of 700m, a longitudinal length of 600m and a volume of about 165438+ 1 100 million m3. Sliding bed strata are sandstone and shale of Middle and Lower Jurassic. This landslide directly threatens the life and property safety of 49 households with 2 1 1 people and 90 households with 352 people around, which will have a certain impact on the shipping of Chishui River. In 200 1 year, the Ministry invested 300,000 yuan for investigation, and in 2002, the provincial government invested 300,000 yuan for emergency treatment of No.2 landslide, which initially curbed the expansion of the landslide.

The above seven projects were investigated, demonstrated and managed, and the investment was * * *14.75 million yuan, of which the Ministry invested 7 million yuan and the province raised 7.45 million yuan.

3 geological disaster management problems

As mentioned earlier, there are many geological disasters in Guizhou Province, which are prone to occur and do great harm. In addition to taking necessary evasive measures and monitoring, early warning and forecasting, many of them are manageable but uncontrollable. Judging from the effects of several typical geological disasters in Guizhou Province, the demonstration-driven effect is very remarkable, but it is generally the result of joint investment by the state and local governments. Through governance practice, it is considered that there are mainly the following problems:

(1) It is difficult to predict the possible location and time of geological disasters due to insufficient understanding of geological environment and inaccurate understanding of geological disaster base. Although1∶ 500,000 environmental geological survey was conducted, the scale was too small. It is a good thing to carry out the investigation and division of geological disasters in counties (cities) now, but the progress is slow. In addition, the functions of provincial geological environment monitoring stations and sub-stations at the prefecture (city) level are difficult to be put in place, information cannot be concentrated, and comprehensive analysis and research are not enough, which is also an important reason for the passive work.

(2) The knowledge and principles of geological disaster prevention and control are not widely publicized, and grass-roots workers lack the ability to judge geological disasters and are not sure about the prevention and control work. Whether it is a geological disaster or not, the phenomenon of random exaggeration and blind upward has occurred from time to time.

(3) The management of geological disasters lacks unified planning, the professional team is not well integrated with government departments, and technology is out of touch with economy. Even if the plan was made, it was not approved by the higher government, which made the plan impossible to implement and difficult to implement. In practical work, it is often in a "passive emergency" situation.

(4) There is no stable funding channel for the control of geological disasters, and it is difficult to implement the control funds. Although governments at all levels are required to include the funds for prevention and control of geological disasters in the fiscal budget, it is difficult to put them in place in practice because of the lack of rigid regulations. Generally speaking, the first thing that comes to mind is to apply for subsidies upwards. It is absolutely impossible to squeeze out some funds at the right time and take emergency measures of "treating the headache and treating the foot pain". The localities lack the initiative and enthusiasm they deserve.

(5) The project management system is not smooth, and the project legal person responsibility system is not strictly implemented. Due to the influence of power factors in real work, even after the project is issued, it is often the case that the project legal person can only be passively managed or even unable to manage, such as "matching with others" and redistributing projects. Who will the project be awarded again, how much, how much progress and how much quality? It is difficult for the project legal person to know. This has also produced a series of problems such as financial final accounts and data collection. This is inconsistent with the current financial budget management method and the legal responsibility that the project legal person should bear.

(6) The relevant laws and regulations on geological disaster control are not matched, and there is no strict technical, operational and economic basis. As a special discipline, geological disasters are related to the national economy and people's livelihood, and the present situation is extremely disproportionate to its status. In practical work, we can only refer to the standards and quotas of construction, highway, railway, water conservancy and other industries and departments. It should be said that there is still a certain gap in operation.

4. Implement the countermeasures and measures of geological disaster control.

In 2003, the Ministry of Land and Resources clearly pointed out at the national conference on geological environment management that the prevention and control of geological disasters is the top priority of geological environment protection, and efforts should be made to realize the change from the scattered and passive emergency situation in the past to the organized, professional and active situation. In order to solve a series of problems of sustainable development, we must correctly handle the relationship between economic development and geological environment protection, thoroughly implement the principles and policies of geological disaster prevention and control, solve the problems from the mechanism, system and legal system, and standardize the governance work with the system. On the one hand, geological disasters are inevitable objectively, but we can try to reduce and contain them; On the other hand, people can understand and study the formation, development and evolution of geological disasters, and take preventive measures in line with objective natural laws to minimize the losses caused by geological disasters to human beings. According to the characteristics of geological disasters in Guizhou Province, the following countermeasures are put forward for reference.

(1) Strengthen the professional and technical role of the provincial geological environment monitoring station in geological environment protection and geological disaster prevention, carry out in-depth investigation and research on geological environment and geological disasters in the whole province, fully grasp the basic data and information of the whole province, actively join hands with meteorological departments on the basis of strengthening the construction of "three nets", and explore new ways of meteorological early warning in flood season suitable for provincial conditions, so as to truly make the station a high-tech and authoritative geological disaster prevention and research center covering the whole province in the new period. In view of the different ownership, system, basic conditions and work levels of provincial terminals, it is suggested that the Environmental Department of the Ministry, China Geological Survey and China Geological Environment Monitoring Institute strengthen the leadership and work deployment of the terminals, and further clarify the problems existing in the terminals after investigation and study, so as not to neglect management and go their own way because of the localization of the team. Only in this way can the main station become the business and technical support of China Geological Environment Monitoring Institute and the land and resources departments at all levels in the province.

(2) Strengthen the popularization of knowledge and professional training for the masses and grass-roots staff in geological disaster-prone areas, so that they can understand geological disasters and the general preventive measures, governance rules and procedures of geological disasters. Practice has proved that there is a great difference between propaganda and training in dealing with disasters.

(3) To do a good job in the planning of geological disasters, we should not only have the active participation of professional teams, but also have the close cooperation of government departments. Only in this way can we work out a comprehensive plan with strong operability according to local conditions, which will be promulgated and implemented after being demonstrated by experts and approved by the government. According to the prevention and control principles formulated by the state and the governance plan compiled by the superior, the key points are highlighted in space, time, measures and management, and adjustments are allowed according to changes in the situation, but the tasks must be clear, the measures and responsibilities must be clear, and it is easy to operate and implement.

(D) dredge and establish a stable fund channel for the control of geological disasters, gradually realize the diversification of control funds, and conscientiously implement the geological disasters caused by natural factors as stipulated in the Regulations on the Prevention and Control of Geological Disasters, and the geological disasters caused by human activities such as engineering construction shall be borne by the responsible units. From the central government to the local government, a certain amount of funds or special management funds should be established to ensure the emergency management of major geological disasters and complete the management tasks of planning and deployment. At the same time, according to "who induces, who governs; Take the principle of "whoever governs will benefit" and adopt a combination of coercion and encouragement to obtain more funds. We should also open up other channels, such as mineral resources compensation fees, mine environmental restoration fees, land consolidation fees, etc., and strive to use some of them, including social sponsorship, to help raise funds in various ways. At present, in the case of poor capital channels, we should continue to carry out demonstration management of typical geological disasters, give full play to the enthusiasm of the state and local governments, and use the encouragement policy to invest in governance projects to publicize and commend the project achievements and investors who have achieved good social and economic benefits, so that this policy is deeply rooted in the hearts of the people.

(5) Resolutely implement the project legal person responsibility system. The project legal person has the right to comprehensively manage the project according to law, and at the same time has the obligation to complete the task according to quality and quantity and bear corresponding legal responsibilities. In principle, public welfare work should be entrusted to local public welfare organizations, and those with insufficient strength can be completed through cooperation with relevant qualified units. Government departments' inspection and acceptance of project implementation procedures and achievements is liberated from tedious project management and performs its macro-control and management functions. In this way, the centralized management of geological disasters in the whole province provides first-hand information for compiling the regulations and norms of this industry, which is of great benefit to improving the research level and quality of geological disasters in this department, and government management and career support complement each other.