探讨土地利用变化所引发的水质净化演变,对于保护和改善水质,实现可持续发展具有重要意义。以“两湖一库”流域为例,运用PLUS(patch-level land use simulation)模型和InVEST(integrated valuation of ecosystem services and tradeoffs...探讨土地利用变化所引发的水质净化演变,对于保护和改善水质,实现可持续发展具有重要意义。以“两湖一库”流域为例,运用PLUS(patch-level land use simulation)模型和InVEST(integrated valuation of ecosystem services and tradeoffs)模型生态系统服务水质净化模块,基于2000年、2010年和2020年土地利用数据,模拟流域在未来自然发展情景和生态保护情景下的用地类型时空格局变化以及水质净化特征。定量揭示土地利用变化与水质净化功能的响应关系。结果表明:“两湖一库”流域土地类型以耕地为主,2030年在自然发展情景下耕地、林地、草地面积呈下降趋势,建设用地呈上升趋势,生态保护情景可有效保护流域耕地、林地等空间分布和面积;“两湖一库”流域TN、TP输出量以低强度输出为主,2000—2020年TN输出量先增加后减少,TP输出量逐年增加,水质净化能力呈稳中变好的趋势;2030年自然发展情境下TN输出量持续减少,TP输出量呈向上浮动,生态保护情景下TN、TP输出量较自然发展情景下减少,生态保护情景可以增加水质净化能力。生态用地类型可以有效截留N、P进入水体,生态保护情景下有效降低生态用地类型的变化速度,减少TN、TP的输出量,“两湖一库”流域未来规划中应增加生态用地的占比,增加土地类型对TN、TP的截留能力。展开更多
The Nile Delta is considered to be one of the most vulnerable river deltas to Sea Level Rise (SLR) in the world. SLR is expected to affect large agricultural areas of the Nile Delta, either through inundation or highe...The Nile Delta is considered to be one of the most vulnerable river deltas to Sea Level Rise (SLR) in the world. SLR is expected to affect large agricultural areas of the Nile Delta, either through inundation or higher levels and salinity of groundwater. It could be argued that such impacts would augment the problems experienced already in the area in terms of high groundwater table and salinity levels. In order to guide policy and decision making, especially in terms of assessing the economics of various adaptation options, there is a need to provide estimates of potential economic damage that could result from such changes. The paper in hand aims to estimate the economic value of potential primary impacts of higher levels of groundwater table due to expected SLR on agriculture productivity in Damietta Governorate as one of the Nile Delta coastal governorates. To conduct such an assessment, relationship between groundwater table level and agricultural productivity was first investigated in relevant literature. This was followed by reviewing prevailing conditions in the agricultural sector in the study area. Thereafter, a regression analysis for the main crops in the study area, between crop yield and groundwater table levels, was conducted. Based on the developed regression, a GIS (Geographic Information System)-based hydrological model, and a production economic model, were employed to assess economic value of higher levels of groundwater table impacts on agriculture productivity. It was found that future accumulative crop yield loss was estimated, using segmented linear regression, up to the year 2100 to be as much as L.E. 6.43 billion. It is worth mentioning that these estimates do not include indirect impacts of higher levels of groundwater table, which may include loss of jobs and/or earnings, impacts on food supply and food security in the area. A potential adaptation option, namely redesigning and upgrading existing drainage infrastructure, was found to cost a total of L.E. 190.8 million, representing abo展开更多
文摘探讨土地利用变化所引发的水质净化演变,对于保护和改善水质,实现可持续发展具有重要意义。以“两湖一库”流域为例,运用PLUS(patch-level land use simulation)模型和InVEST(integrated valuation of ecosystem services and tradeoffs)模型生态系统服务水质净化模块,基于2000年、2010年和2020年土地利用数据,模拟流域在未来自然发展情景和生态保护情景下的用地类型时空格局变化以及水质净化特征。定量揭示土地利用变化与水质净化功能的响应关系。结果表明:“两湖一库”流域土地类型以耕地为主,2030年在自然发展情景下耕地、林地、草地面积呈下降趋势,建设用地呈上升趋势,生态保护情景可有效保护流域耕地、林地等空间分布和面积;“两湖一库”流域TN、TP输出量以低强度输出为主,2000—2020年TN输出量先增加后减少,TP输出量逐年增加,水质净化能力呈稳中变好的趋势;2030年自然发展情境下TN输出量持续减少,TP输出量呈向上浮动,生态保护情景下TN、TP输出量较自然发展情景下减少,生态保护情景可以增加水质净化能力。生态用地类型可以有效截留N、P进入水体,生态保护情景下有效降低生态用地类型的变化速度,减少TN、TP的输出量,“两湖一库”流域未来规划中应增加生态用地的占比,增加土地类型对TN、TP的截留能力。
文摘The Nile Delta is considered to be one of the most vulnerable river deltas to Sea Level Rise (SLR) in the world. SLR is expected to affect large agricultural areas of the Nile Delta, either through inundation or higher levels and salinity of groundwater. It could be argued that such impacts would augment the problems experienced already in the area in terms of high groundwater table and salinity levels. In order to guide policy and decision making, especially in terms of assessing the economics of various adaptation options, there is a need to provide estimates of potential economic damage that could result from such changes. The paper in hand aims to estimate the economic value of potential primary impacts of higher levels of groundwater table due to expected SLR on agriculture productivity in Damietta Governorate as one of the Nile Delta coastal governorates. To conduct such an assessment, relationship between groundwater table level and agricultural productivity was first investigated in relevant literature. This was followed by reviewing prevailing conditions in the agricultural sector in the study area. Thereafter, a regression analysis for the main crops in the study area, between crop yield and groundwater table levels, was conducted. Based on the developed regression, a GIS (Geographic Information System)-based hydrological model, and a production economic model, were employed to assess economic value of higher levels of groundwater table impacts on agriculture productivity. It was found that future accumulative crop yield loss was estimated, using segmented linear regression, up to the year 2100 to be as much as L.E. 6.43 billion. It is worth mentioning that these estimates do not include indirect impacts of higher levels of groundwater table, which may include loss of jobs and/or earnings, impacts on food supply and food security in the area. A potential adaptation option, namely redesigning and upgrading existing drainage infrastructure, was found to cost a total of L.E. 190.8 million, representing abo
