Search

Ecosystem services are closely related to human well-being, and the study of the trade-offs and synergies between ecosystem services is currently a pressing research topic. By analyzing its conceptual connotation and research characteristics, we can better understand the relationship between the regional ecosystem services, adapt to the need of the parties to maximize the overall benefits, and provide a basis for decision-making for regional development. This study focused on the literature quantitative characteristics of domestic and foreign research on ecosystem services trade-offs and synergies from 1996 to 2020 by literature analysis and comparative analysis. Domestic and foreign research themes from different periods, from the beginning of development to the present, were analyzed. The conceptual connotation and research characteristics of the trade-offs and synergies of ecosystem services were summarized. Finally, shortcomings existing in current research and future research directions were identified. The specific conclusions are as follows: the number of domestic and foreign studies is increasing, with the foreign growth rate faster than domestic; Ecosystem service trade-offs and synergies are strongly dependent on time and space scales, the difference of spatio-temporal scale jointly drives the dynamic change of the relationship between trade-offs and synergies, but there is still a lot of research space in this field. In the future, it is necessary to strengthen the research on the framework model, quantitative analysis, driving mechanism, internal mechanism, threshold effect, supply and demand of temporal and spatial changes to better understand the mechanism of temporal and spatial changes in ecosystem service trade-offs and synergies, and achieve a mutually beneficial situation for regional ecological environment and socioeconomic development.

Soil construction and revegetation are essential for ecological restoration in mining areas. The influence of vegetation on the horizontal and vertical distribution patterns of soil properties should be fully understood. However, most studies on reconstructed soils in mining areas only concentrate on the surface soil, without exploring the vertical variations in soil properties. Overall, this study aims to explore the potential mechanisms by which surface vegetation exerts some influence on the spatial distribution of soil physicochemical properties, and to provide some insight into revegetation and soil reclamation in mining areas. Descriptive statistics and one-way analysis of variance (one-way ANOVA) were employed to evaluate the differences in the soil physicochemical properties in horizontal and vertical directions under different land-use types in the south dump of Antaibao opencast mine in Pingshuo, Shanxi Province, China. The main results of this study are as follows: (1) In the horizontal direction, except for the strong variation (variation coefficient ≥ 100%) in soil organic matter (SOM) content at some depths, the degree of variation in other soil physicochemical properties at various depths was moderate or weak (variation coefficient < 100%). The soil physicochemical properties gradually remained constant after years of reclamation. In the vertical direction, the soil bulk density (SBD), soil porosity, SOM content, soil C/N ratio, soil total nitrogen (STN) content, soil available phosphorus (SAP) content, and soil available potassium (SAK) content showed significant variations (p < 0.05) between soil depths. In contrast, no significant difference was found for other physicochemical properties. (2) The SBD, STN, SAK, soil porosity, and soil clay content were significantly different (p < 0.05) under different vegetation cover types, but the influence of vegetation on other soil physicochemical properties seemed to be limited. The results reveal that trees have a stronger ability to reduce soil grain sizes and enhance SAP contents than shrubs or herbs; however, the beneficial effects of herbs on the physicochemical properties of shallow soil are more obvious than those of trees and shrubs. (3) This study indicates that more shrubs and trees should be planted in the areas with low vegetation coverage, and more measures should be taken to improve soil physicochemical properties in order to prevent the occurrence of large-scale degradation. The reconstruction of soil structure should be preferentially considered in the process of soil reconstruction and revegetation in areas under similar conditions. Herbs should first be planted in the early reclamation stage. At the same time, shrubs or trees can be adopted in the middle and late stages of vegetation reconstruction in order to achieve comprehensive revegetation.

A novel fusion method based on the hyperspherical color transformation (HCT) and joint sparsity model is proposed for decreasing the spectral distortion of fused image further. In the method, an intensity component and angles of each band of the multispectral image is obtained by HCT firstly, and then the intensity component is fused with the panchromatic image through wavelet transform and joint sparsity model. In the joint sparsity model, the redundant and complement information of the different images can be efficiently extracted and employed to yield the high quality results. Finally, the fused multi spectral image is obtained by inverse transforms of wavelet and HCT on the new lower frequency image and the angle components, respectively. Experimental results on Pleiades-1 and WorldView-2 satellites indicate that the proposed method achieves remarkable results.