The United States and Germany were the first countries to start reclamation. Land reclamation in the United States is mainly developed from the reclamation of open-pit coal mines. 19 18 conducted a plant replanting experiment in the gangue hill of Indiana coal mine. American scholars mainly study the reclamation of open-pit mines (especially coal mines) and mining wasteland, and pay attention to the research of soil reconstruction and improvement methods, vegetation regeneration technology, agricultural and forestry production technology and erosion control technology. In recent years, the research in the United States has paid special attention to the long-term and sustainability of reclamation, and bioremediation and the ecological environment around reclamation areas have become its research focus.
Germany has higher requirements for reclamation. German scholars comprehensively consider ecological benefits and environmental benefits, and take the changes of the whole ecosystem and people's requirements for the environment as the starting point, and the concept of "people-oriented" is more obvious. Germany's reclamation model basically continues the traditional reclamation technology of topsoil stripping-excavation, backfilling and filling-topsoil covering-fertilization, but its specific methods and technologies are advanced, and it pursues the maximization of social, economic and ecological benefits while maintaining the ecological environment balance in the reclamation area. At present, Germany has developed from reclamation for agriculture and forestry to a comprehensive land for species protection, soil biological reconstruction and ecological leisure tourism, which is a mixed land reclamation model.
Canada has studied land reclamation in many fields, paying special attention to the reclamation of land polluted by oil, oil shale and various toxic and harmful substances. Canadian scholars believe that land reclamation does not require restoring the original appearance, but requires local conditions, but it cannot be lower than the original ecological level. Canada not only organizes the annual international land reclamation conference and edits and publishes the magazine International Open-pit Mining, Reclamation and Environment, but also the government provides financial support for land reclamation research.
Australia's land reclamation and development management is considered to be the most advanced country to successfully deal with damaged land. The Australian government has formulated a series of strict legislative frameworks, and all indicators related to reclamation are clearly defined. Most land reclamation in Australia adopts the mode of "mining while reclamation", and pays attention to the research and application of reclamation technology. At present, many technologies are at the leading level in the world. Under the supervision of law, government and the public, land reclamation has become the conscious behavior of the state reclamation obligor.
Britain also adopts the model of "reclamation while mining", which greatly reduces the area of land loss. The British government also decided to allocate land reclamation funds to local governments according to the economic level of the damaged land. The reclaimed land belongs to the local government, which manages it by itself to make up for the shortage of reclamation expenses. Due to the implementation of policies and funds, land reclamation in Britain has achieved remarkable results.
In addition, Yuri Gorokhovich and others used GIS technology to study the reclamation of abandoned land in mining areas. Sahadeb De et al. used bioengineering reclamation measures to study the abandoned land in Rani Gan Jie coalfield in eastern India, and screened out plants suitable for local reclamation; Demetris Damigos, etc. Various evaluation models are used to evaluate the environmental impact of coal mine reclaimed land in Greece, and the reclamation countermeasures are put forward. Duglas Baker studied the application of synthetic materials in pure biological reclamation technology and soil-free anti-erosion technology. Robert B.Atkinson believes that the wetlands in Virginia should also be included in the ecological environment restoration process of coal mine wasteland; Richand J.Hobbs put forward that "retaining large patches and facilitating traffic are the key to land reclamation, and then vegetation restoration" through the experimental study of ecological environment reconstruction. Dimitris Kaliampakos, Dimitris Damigos and others analyzed the evaluation methods of environmental benefits and economic benefits of land reclamation in mining areas, which played a positive role in the planning and construction management of land reclamation in mining areas.
Foreign research on land reclamation has the following characteristics:
(1) The laws and regulations are sound. The leading countries in land reclamation research abroad have formulated strict and perfect laws and regulations, and have special management institutions to ensure the implementation of reclamation and achieve a high reclamation rate.
(2) Multi-disciplinary and multi-field. Land reclamation attracts experts and scholars in the fields of mining, agriculture, forestry, soil, ecology, chemistry, geology, biology and management, which greatly promotes the research and development of land reclamation.
(3) the change of direction. The research of land reclamation has expanded from the initial coal mine reclamation to other types of damaged land reclamation such as mining, pollution, natural disasters, hydropower construction and man-made destruction. Reclamation measures have also changed from engineering reclamation to ecological reclamation, and more ideas and principles of sustainable development have been used.
(4) internationalization and industrialization. The trend of internationalization is increasingly obvious, and the exchanges and cooperation between countries are closer; The development of reclamation industrialization is more obvious.