Reclamation Modes Research Articles

Spatial-temporal characteristics and transfer modes of rural homestead in China

Spatial-temporal characteristics and transfer modes of rural homestead in China

Characteristics of the Thermal Environment and its Guidance to Ecological Restoration in a Resource-Based Area in the Loess Area.

The thermal environment is a crucial part of ecological environments. It is vital to study the distribution and generation of thermal environments for regional sustainable development. Mining area, agricultural area and urban area were taken as the research object, and remote sensing data were used to study the spatiotemporal distribution characteristics of the thermal environment. The relationship between the thermal environment and land use types was analyzed, and the effect of mining and reclamation on the thermal environment was emphasized. The main findings were: (1) the thermal effect zone in the study area was dispersed. The area ratio of the thermal effect zone accounted for 69.70%, 68.52%, 65.85%, 74.20% and 74.66% in the year 2000, 2003, 2009, 2013 and 2018, respectively. The contribution to the overall thermal effect was in the order of agricultural area > mining area > urban area. (2) The proportion of forest and the average grid temperature always showed a significant negative correlation in different scales and had the highest correlation and the greatest influence. (3) The land surface temperature (LST) of opencast areas was higher than the surrounding temperature, and the temperature difference was 3-5 °C. The LST of reclaimed sites was lower than the surrounding temperature, and the temperature difference was -7 to 0 °C. The quantitative study found that reclamation mode, shape and spatial location could affect the cooling effect of the reclaimed site. This study can provide a reference for the mitigation of thermal effects and the identification of influences of mining and reclamation on the thermal environment in the coordinated development of similar regions.

Analysis of the reclamation measures efficiency within watershed and their impact on the water bodies

The results of the detailed analysis of reclamation measures to improve the quality of water and land resources in the territory of the Sheshma River basin in Tatarstan are given in the paper. The classification of factors affecting the pollution of diffusive runoff coming from agricultural land, as well as measures to reduce water pollution and classification of methods to prevent water pollution of runoff coming from the reclaimed land and rural areas are developed. All methods on water and land quality improvement in the catchment area of the river are divided into 5 groups according to main issues and localization. The efficiency of the above groups of reclamation measures are determined on the base of water management balances including maximum pollution coefficients estimation. The analysis was carried out and the factors influencing the efficiency of the recommended measures on water and land detoxification were recommended. The factors that have the greatest impact on the efficiency of the recommended measures are: the degree of erosion of land resources in the catchment area, reclamation modes, the availability of drainage, the quality of irrigation and drainage waters. Some recommended ranges the recommended measures application are given takin into account hydrogen indicator, texture on soil, drainage flow salinity, contamination of surface runoff from agricultural lands with heavy metals, pesticides, etc..

Ecosystem service valuation of bays in East China Sea and its response to sea reclamation activities

Ecosystem service values (ESVs) of bays and their response to sea reclamation are of great practical importance for forming bay eco-compensation policy and extension of blue economic space. Based on land use information of bays collected during the period of 1990–2015, the spatiotemporal evolution of ESVs of 12 main bays in East China Sea and their response to sea reclamation activities over the past 25 years were quantitatively analyzed. The analysis results indicate that ESVs of bays in East China Sea showed a continuous downward trend and the whole ecosystem was continuously degraded, in which the degradation degree of ESV in the southern bays was higher than that in the northern bays. Spatial zoning of ESVs of bays in East China Sea was remarkable, showing a continuous downward trend from low-value to high-value zone. Spatial variation of ESVs of each bay was also significant, expanding from a city and from inland to the coast, which suggests that human activities, mainly reclamation, have become main agents for ESV evolution of bays in East China Sea. ESVs of bays have a significant response to sea reclamation, manifested as a significant negative correlation between ESV and reclamation intensity. The correlation in the southern bays was stronger than that in the northern bays, which was caused by different effects of sea reclamation modes on ESV evolution of muddy and bedrock bays. A negative effect of sea reclamation activities on bay ecosystem was hysteretic. Therefore, an attention should be paid to dynamic monitoring and early warning of development status in offshore areas, ecosystem-level reclamation control policy, and coastal wetland reserves planning. Moreover, the spatial coupling mechanism study between bay ecosystem service demand and its service supply capacity should be strengthened to realize systematic regulation of bay ecological security pattern.

Coupled variations of soil temperature and moisture in reclaimed fields filled with coal gangue of different grain size distributions

This study was aimed at investigating the effects of different reclamation modes on coupled variations of soil temperature and moisture. An experimental field was established, which consists of three plots (plots I, II, and III) filled with coal gangue of different grain size distributions (coarse grain, middle-coarse grain, and fine grain) and covered with the same thickness (50 cm) of soil. Temperature and moisture at four depths (10, 25, 50, and 65 cm) in three plots were monitored and analyzed. The study reveals that both in winter and summer soil temperature at each depth was highest in plot III and lowest in plot I. Although plot III performed better in heat preservation in winter, soil temperature of which was too high in summer for crop growth. The results also indicate that annual average of soil moisture at the depth of 10 cm and 25 cm was highest in plot II, namely plot II performed best in water holding in the tillage layer for the whole year. Soil temperature and moisture in plot II were more conducive to crop growth on the whole, and it is recommended to adopt the reclamation mode of plot II for land reclamation in coal mining subsidence areas with high ground water table.

Impact of Different Reclamation Modes of Fly Ash Deposits on Species Richness of Spontaneous Flora

The model reclamation process of the studied fly ash deposits has been started in 2003 by formation of five different experimental surface layers containing fly ash and organic matter in various combinations. Then, grass mixture was sown on these surface layers. In 2015, selected properties of plant communities growing on different variants of surface layers applied in the reclamation process were assessed. It was assumed that the type of mineral and organic substrates used in the process and their quality were the main factors affecting the long term plant diversity present on different variants of restored surfaces. The aim of this analysis was the assessment of the effectiveness of ash waste reclamation (carried out on five different types of the surface layer) after 12 years since its initiation. The long term results of the reclamation process showed that the applied surface layers allowed for an effective reclamation of ashes since all variants of experimental surfaces were totally covered by dense vegetation. The predominance of plant species from ruderal and segetal habitats indicated that the soil of the experimental habitats was fertile with neutral and slightly alkaline pH, and texture of sandy loams. The experimental surface layers with a texture of sand of favourable C:N ratio, neutral or slightly alkaline did not limit the plant development. The use of organic waste markedly contributed to the floristic diversity of the spontaneously developed vegetation. Coniferous bark used in some experimental variants had a marked effect on their floristic distinctiveness due to the presence of species preferring habitats of lower pH values.

Концептуальные подходы и тенденции развития систем прецизионного управления мелиоративным режимом агроэкосистемы

Formation of conceptual approaches, development and implementation of the systems of precision control of reclamation mode in the practice of agricultural production within the agroecosystems – the key issue of the evolution of the process of automation in the field of land reclamation that meet theoretical and practice requirements of innovative technologies of agriculture in the Russian Federation nowadays. According to the results of the study as well as theoretical and practice generalization of informational digital control system application in the reclamation activities recognized the need for digitalization and automation of technological processes of agricultural production in reclaimed lands was recognized. At the same time, productivity growth in agro-phyto-cenoses guarantees to exceed the effects of mechanization, fertilizers application, the use of the tractors, herbicides, genetically modified seeds, etc. It is shown that the development of high-precision control of the process of the reclamation mode formation is based on the wide use of computers, digital systems, indicators of remote active and passive sensing, robotics, specialized means of mechanization. The basic principles and requirements of the formation of the automated control systems of technological processes to regulate reclamation mode in the agroecosystem, which save the best achievements of the theory in the field of effective and sustainable agricultural production in reclaimed lands are tested in practice. The features of automation at management, operational, tactical and strategic levels of decision – making for micro-, meso- and macrolevels of the hierarchy of the managed area are characterized. The priority directions to improve high-precision management of meliorative mode in agroecosystems regarding to spatial and temporal variability of soil fertility and other conditions within agro-phyto-cenosis differ in the methods of monitoring and specific indicators’ evaluation; determination of the agro-ecologically similar contours of the field/crop rotation; creation of the targeted, object – oriented recommendations, differentiated to each economy, site, culture and biodiversity.

Теоретические подходы к обоснованию систем комплексных мелиораций

On the basis of thermodynamic approach the requirement for the development of the integrated land reclamation projects in all natural zones of the European part of Russia is proved. It is shown, that measures on land reclamation increase the energy fluxes in the agro-ecosystem from 4 to 8 % depending on the climatic zone, reduce the magnitude of the turbulent energy efficiency and the internal energy of the soil system by 20–40 kJ/ha, which give an opportunity to increase crop productivity by 3–5 times in the reclaimed lands as compared to the non-reclaimed ones. In the practice high-tech irrigation and drainage systems with elements of artificial intelligence, gives an opportunity to control the reclamation mode based on the digital technologies of collecting, analyzing, processing information on environmental parameters and automated systems to make operational decisions.

Impacts of Coastal Reclamation on Natural Wetlands in Large River Deltas in China

Little information is available on the impacts of coastal reclamation on wetland loss in large-river deltas at a regional scale. Using remote sensing data of coastal wetland and reclamation in four deltas in China from 1978 to 2014, we tracked their continuous area changes in four periods: 1978–1990, 1990–2000, 2000–2008, and 2008–2014. The areal relation between wetland loss and reclamation was quantified and used to identify coastal reclamation mode intensity coupled with another three indicators: reclamation rate, accretion rate and land-use intensity of coastal reclamation. The results showed that coastal reclamation driven by economic development reduced, or even reverse the original growth of delta which was determined by the offset between wetland acceleration rate and wetland loss rate. Generally, the area of reclamation showed a positive linear correlation with the area of wetland loss. The findings imply that human activities should control reclamation rate and intensity to alleviate total wetland loss and maintain wetland ‘net gain’. Inappropriate coastal reclamation modes can magnify total wetland loss; therefore, coastal reclamation with a slow increment rate and low impervious surface percent is of great importance for sustainable development in future coastal management.

Evaluation of climate changes and their accounting for developing the reclamation measures in western Ukraine

In modern conditions, there are cardinal climate changes on the Earth as at the planetary scale, as at the regional level. According to numerous hydrometeorological characteristics and indicators, climatologists specialists concluded that Ukraine also take place significant climatic changes in the last 10–25 years. In complicated natural-technical systems, which include irrigation and drainage systems (IDS) on drained lands, the selection of regime-technological and technical solutions on different levels of the decision including the time, should be based on the appropriate meteorological information for selecting climatologically optimal management strategies for such systems in the long-term and annual periods. The decisive influence on the formation of water and the overall natural reclamation modes of reclaimed land and harvest crops in many cases depends exactly from climate or weather conditions. Thus, it is necessary to have available data about their implementation to the relevant object as for number of previous years retrospective observations and the forecast period of functioning of the object. Therefore, forecasting of weather and climate conditions become an indispensable condition for implementation of assessing the overall effectiveness of IDS operation. To solve this problem we performed large-scale computer experiment for multi-year retrospective and current data observations in the area of Zhytomyr Polissya. Were planned and implemented the following variants of studies – «Base», «Transitional», «Recent», «CCCM», «UKMO». The forecast was done for five years of typical groups of vegetation periods regarding conditions of heat and moisture provision (very wet – 10%, wet – 30%, average – 50%, dry – 70%, very dry – 90%) on such basic meteorological characteristics: air temperature; precipitation; relative air humidity; defi cit of air humidity; photosynthetically active radiation (PAR); coeffi cient of moisture provision (the ratio of precipitation to evapotranspiration). Obtained results of comparative assess-ment of climatic conditions in Zhytomyr Polissya zone, suggests that for most of the basic meteorological parameters, already there are changes that in the short term may exceed 10% of the critical ecological threshold, which will lead to relevant irreversible changes in the state of the environment in the region.

Assessment of Reclamation Treatments of Abandoned Farmland in an Arid Region of China

Reclamation of abandoned farmland is crucial to a sustainable agriculture in arid regions. This study aims to evaluate the impact of different reclamation treatments on abandoned salinized farmland. We investigated four artificial reclamation treatments, continuous cotton (CC), continuous alfalfa (CA), tree-wheat intercropping (TW) and trees (TS), which were conducted in 2011–2012 in the Manasi River Basin of Xinjiang Province, China. Soil nutrient, microorganism and enzyme activity were examined in comparison with natural succession (CK) in an integrated analysis on soil fertility improvement and soil salinization control with these reclamations. Results indicate that the four artificial reclamation treatments are more effective approaches than natural restoration to reclaim abandoned farmland. TW and CA significantly increased soil nutrient content compared to CK. CC reduced soil salinity to the lowest level among all treatments. TW significantly enhanced soil enzyme activity. All four artificial reclamations increased soil microbial populations and soil microbial biomass carbon. TW and CA had the greatest overall optimal effects among the four treatments in terms of the ecological outcomes. If both economic benefits and ecological effects are considered, TW would be the best reclamation mode. The findings from this study will assist in selecting a feasible method for reclamation of abandoned farmland for sustainable agriculture in arid regions.

The Topsoil Quality Variation Under Different Reclamation Modes in Pasture Opencast Coal Mine of China

As the lack of topsoil resources, and the shortage of water resources, the ecological environment is extremely fragile in the pasture opencast coal mine area of China. Therefore, that the way to achieve the most efficient use of the limited topsoil resources in pasture area, plays a crucial role in land reclamation and ecological restoration. East II opencast coal mine in Datang, Inner Mongolia was taken as an example to analyze topsoil quality variation under different dump platform and slope reclamation modes in the pasture opencast coal mine area. The field investigation method was used in this paper. The study found that the mode "covering topsoil, overlying grass, grass grid, N fertilization, planting vanguard vegetation" in dump platform and "covering topsoil, overlying grass, grass grid, planting vanguard vegetation " in dump slope can lead to the best topsoil quality, though it still less than the original landscape topsoil quality level. The research can provide technical support and scientific basis for the pasture reclamation and ecological restoration.

Re-use strategy of subsided land based on urban space ecological compensation: case study for Xuzhou mining area for example

Abstract In this paper, based on a new definition we propose for “urban space ecological compensation” from view of ecology, we summarize the space-time development law of subsided land in Xuzhou mining area, and describe the ecological degradation characters of subsided land and the present status of land-use, obtaining a conclusion that the present reclamation mode can not meet the existing conditions of subsided land, such as large subsided area and dynamic change, large volume of accumulated water, and complex landform. In addition, the standard of reclamation was changed in new reclamation regulation. Therefore, we analyze the internal relation between subsided land and urban space structure with the idea of urban space ecological compensation and try to discover the great value of ecosystem service function of subsided land, which can help to realize ecological balance of urban space. At last, we put forward a strategy for re-use of subsided land based on the principle of ecological compensation, that is, “the minimal manual intervention” and “the largest ecological efficiency”, in which subsided land is regarded as a new resource that can promote urban-rural harmonious development and sustainable development in mining area.