Planting Green Seeds in Cold Open-pit Coal Mines

Liqiu, overlooking Huolingole City, located at the southern foot of the Great Hinggan Mountains, has green hills and green grass. This grassland coal city built by coal and built by coal is bringing vitality to life. Here, the total capacity of five open-pit coal mines affiliated to the State Electricity Investment Inner Mongolia Company has reached 81 million tons per year, accounting for 12.5% of the total capacity of open-pit coal mines in China. How to build the Grassland Coal City into a green mine benchmark is a question that the State Electricity Investment Inner Mongolia Company has been thinking about. Last June, the Second Environmental Protection Supervision Group of the Central Committee went to Huolin Henan Open-pit Coal Mine and North Open-pit Coal Mine to inspect. It pointed out that the enterprise had insufficient investment in reclamation funds and little efforts in ecological restoration and management. Liu Jianping, general manager of Inner Mongolia Electric Power Investment Corporation of China, said that the company had established the working goal of "one year of great change, three years of thorough rectification and building a benchmark for green mines in alpine regions of China", and invited the Chinese Academy of Environmental Sciences to prepare a special plan for ecological restoration and increase investment in reclamation funds.

"In a ton of coal sold, the investment in reclamation increased to 5 yuan." Zhao Yu, chief expert of coal mining in Inner Mongolia State Power Investment Corporation, said, "Over the past year, the total investment of 246 million yuan has been made in the South and North open pits, and the reclamation of 2,074 mu of mines has been completed, thus realizing the goal of reclamation investment to"make up the old accounts and not owe the new ones". 

The Chinese Academy of Environmental Sciences put forward the design concept of "open channel and dark cellar, sponge dump, drainage and storage, and ecological open pit mine" in the special plan of ecological restoration. Biological measures should be taken to restore the vegetation system, and engineering measures should be taken to consolidate and create the site conditions of organisms.

"We strive to build a self-sustaining and maintenance-free natural ecosystem, which will have functions of soil and water conservation, wind and sand control, biodiversity and so on." Sude, chief expert of the Chinese Academy of Environmental Sciences, said. Yuan Guangzhong, chief engineer of Inner Mongolia Television Investment Corporation of China, said that in order to achieve this goal, they had conducted a variety of plant planting experiments. Sixteen drought-tolerant, cold-tolerant, well-developed roots, strong soil-fixing ability and suitable plants for the local growth environment were selected. Taking pioneer species as the guide, taking into account perennial plant species, three-dimensional plant planting of trees, shrubs and grasses was carried out to form a natural succession community structure. Water shortage is a big problem. The annual average precipitation of Hollingol is 358 mm, and most of the precipitation is concentrated in summer. Rain is less and concentrated, seeds are not easy to germinate, seedlings are not easy to take root, even if they survive, the dry and rainless climate will make plants fall leaves ahead of time. The solution is to build micro-sprinkler irrigation, drip irrigation and other projects in the dump of the mining area. Most of the rainwater is stored in the reservoir, and the problem of water shortage is alleviated. Feng Wanguo, head of North Open-pit Coal Mine, said, "In order to make drainage ditches and vegetation melt together, we mix cooked soil with chicken manure and plant seeds into environmental protection bags. When the plants grow out, the environmental bags will melt into the soil and the drainage ditches will be hidden in the vegetation.

In addition, two open-pit mines in South and North Open-pit Coal Mines are located in high and cold areas. The frost-free period of the whole year is only 3 months. The annual average temperature is below 0.5 degrees Celsius, and the extreme temperature is below 37.2 degrees Celsius. The soil is relatively barren. This is also a major obstacle to reclamation.

"To smash down the real gold and silver fields, we have increased investment and planted a variety of annual and perennial plants." Zhao Yu said.

At the South and North Open-pit Coal Mines, reporters saw that the original BLACK-GREY slag had been re-covered with soil, and gradually upward planted with seabuckthorn, Astragalus adsurgens, Sedum notoginseng, alfalfa, Caragana microphylla and other large areas of vegetation. From a distance, you can see patches of rapeseed flowers. The grass came out, the bushes grew up, the rabbits came, and the pheasants came. There is still a long way to go for ecological restoration. Now, after one year's ecological restoration and management of mines, 2074 mu of open pit mines have been reclaimed in the South and the north. Among them, more than 700,000 trees and shrubs were planted, 10 pumping stations, 8 water storage pools, nearly 30,000 meters of water supply pipelines, 15,000 meters of drainage ditches and 6,000 meters of ecological retaining walls were built.

"Mine reclamation should highlight the characteristics of green, safe, efficient, intelligent and harmonious, fully understand the adaptability of vegetation to the local environment, and build stable communities." Wu Gang, Ph.D., Center for Ecological Environment Research, Chinese Academy of Sciences. At present, the company has invested more than 71,000 people in the ecological restoration project of open-pit mines, 14,000 sets of loaders, seeders and other mechanical equipment, with a capital investment of over 600 million yuan. Over the past year, the State Power Investment Inner Mongolia Corporation has also completed the ecological management of other mines. The completion rate of new dump shaping has increased from 50.8% to more than 82%, the slope angle of dump steps has decreased from more than 35 degrees to less than 30 degrees, the reclamation and greening rate should be increased from less than 92% to 97%, and the vegetation coverage should be increased from less than 35% to 51.5%.

If we said that in the past we had to rely on the development of war, now we have to rely on the "great protection" of the traced iron and the imprinted stone, and take "green" as the lifeline of sustainable development.

"This is just the beginning. Restoration of ecological management takes time. Now we are mainly planting annual and perennial crops to improve vegetation coverage. Wang Jingwei, head and chief engineer of South Open-pit Coal Mine, said.

"The mines of Inner Mongolia Company are located in the alpine region, where there is little rain and drought.