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This study measures the impact of fanya juu terraces on the net value of crop income in a high‐rainfall area in the Ethiopian highlands using cross‐sectional multiple plot observations. Using propensity score matching methods we find that the net value of crop income for plots with fanya juu terraces is lower than for plots without fanya juu terraces. This finding makes it difficult to avoid concluding that while the technologies might reduce soil erosion and associated off‐site effects, they do so at the expense of poor farmers in the Ethiopian highlands. Therefore, fanya juu terraces cannot be characterized as a “win‐win” measure to reduce soil erosion. New agricultural technologies need to be profitable to the farmer if they are to be adopted and sustained.  相似文献   

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Evidence from cross-sectional growth regressions suggests that economies dependent on natural resource exports have had slower growth than resource scarce economies. Explanations for this “curse of resources” focus on institutional and market failures caused by resource abundance. With a simple two sector model exhaustible resource model, we demonstrate that the correlation between growth and natural resource abundance can be negative in the absence of market and institutional failures. Since there is no way to distinguish between efficient and inefficient equilibria on the basis of the negative correlation between growth and resource abundance, finding that correlation is not sufficient to conclude resources are a curse, nor is it necessary to find a positive correlation between growth and resources to overturn the resource curse interpretation. We show whether resources are a curse or a blessing for an economy can only be determined by an investigation of the correlation between resource abundance and income levels. Using panel data for U.S. states for the period 1970-2001, we show that resource abundance is negatively correlated with growth rates but positively correlated with income levels.  相似文献   

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This paper provides examples from the last fifty years of scientific and technological innovations that provide relatively easy, quick and affordable means of addressing key water management issues. Scientific knowledge and technological innovation can help open up previously closed decision‐making systems. Four of these tools are discussed in this paper: a) the opportunities afforded by virtual water trade; b) the silent revolution for beneficial use of groundwater; c) salt water desalination; and finally, d) the use of remote sensing and geographic information systems (GIS). Together these advances are changing the options available to address water and food security that have been predominant for centuries in the minds of most water decision‐makers.  相似文献   

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This study aims to investigate the impact of eco-friendly technology on environmental degradation indicated using the load capacity factor (LCF) with the framework of the Load Capacity Curve (LCC) hypothesis. In this regard, an environmental degradation function is formed and analyzed using the Augmented Autoregressive Distributed Lag (AARDL) approach during the period spanning from 1975 to 2021 for India. The outcome indicates that eco-friendly technology reduces the LCF, thereby fostering environmental degradation in the long run, but the relationship is not significant in the short run. Further, an N-shaped LCC hypothesis has been observed in both long and short runs. Besides, energy consumption exhibits a LCF reducing or environmental degradation boosting role in the short run and long run. These findings are consistent with other models that are used to check the robustness of AARDL-based results. Thus, the study recommends policies for promoting eco-friendly technology, judicious economic growth, and cautious energy consumption to attain sustainable development by increasing the LCF in India.  相似文献   

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Understanding the ecological trends of the relict habitats in the Luoshan Nature Reserve (LNR) has an important role in the persistence of endangered species and the socio‐economic sustainability in the Ningxia section of the arid desertification belt in North China. Based on data from the Landsat Multispectral Scanner (MSS)/Thematic Mapper (TM)/Enhanced Thematic Mapper Plus (ETM+)/Operational Land Imager (OLI) sensors (from 1977 to 2017), the MODIS normalized difference vegetation index (NDVI) and net primary productivity (NPP) (from 2000 to 2017), the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM), annual average air temperature and precipitation (from 1977 to 2017), typical anthropogenic factors (population size, cultivated land and residential area) and natural ecological elements (MSS/TM/ETM+/OLI/MODIS NDVI and NPP) were quantitatively contrasted and analyzed for potential correlations. Some indicators of human activities, ecological processes and landscape geography have changed in the LNR. The proportion of residential area increased 3.09‐fold from 1977 to 2017. The population increased 34.30‐fold due to ecological immigration policy implementation in the Hongsipu immigration district. Before immigration, cultivated land increased, but after immigration, this land decreased quickly. Most of the dry‐cultivated land was converted through afforestation and a small part of the land was converted to irrigate cultivation land. We conclude that natural evolution led to the ecological relics, the isolated management to the LNR has objectively created an ecological island that will accelerate inbreeding depression and reduce biodiversity.  相似文献   

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In developed countries, ecological restoration is a widely accepted practice to restore the productivity of degraded coal mine spoils and prevent mine‐degraded sites from acting as sources of pollution. During the past decade, ecologists realized the global need for ecological restoration, and the benefit of restoration is now assessed on the basis of ecosystem services that the restored lands can provide. In this article, the knowledge gap between crude reclamation and ecological restoration is examined, the steps crucial to ecological restoration in tropical conditions are identified, and simple guidelines are given for easy understanding. Restoration issues, such as modification of the forestry restoration approach, reestablishment of biodiversity, removal and reuse of topsoil during progressive and final stages of ecological restoration, drainage, promotion of a plant‐succession‐based approach, use of a grass–legume mixture as an initial colonizer, stabilization of steep slopes, and soil blanketing, are discussed. Those attributes of a degraded ecosystem that are responsible for the success of any restoration project are critically examined, and the opportunities provided by ecological restoration are explored.  相似文献   

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