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Land use/cover in Northeast China went through extensive changes during the 1990s. This report explores the interaction between
these changes and the environment, and the implication of these changes for rational allocation of water resources. Two maps
of land use/cover produced from 1990 and 2000 Landsat TM satellite images were overlaid in ArcInfo to reveal changes in land
cover. Results indicate that farmland and grassland decreased by 386,195 and 140,075 ha, respectively, while water, built-up
areas, and woodland increased by 238,596, 194,231, and 192,682 ha, respectively. These changes bore a mutual relationship
with the environmental change. On the one hand, climate warming made some of these changes (e.g., conversion of woodland and
grassland to farmland) possible. On the other hand, the changed surface cover modified the local climate. These changes, in
turn, caused severe environmental degradation and increased flooding. The change between dry field and rice paddy, in particular,
raised severe implications for the proper allocation of limited water resources in the Northeast. Efforts are needed to coordinate
their rational allocation to reap maximum and sustainable return over the entire area, not just in some localities. Results
obtained in this study should be of interest to the international audience of Environmental Management in that they highlight the interactive nature of human activities and the environment and the off-site impact of these activities
on the environment. 相似文献
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DUAN Guang-ming ZHAO Jing-zhu LIU Guo-hu KE Bing XIAO Han WU Gang DENG Hong-bing 《环境科学学报(英文版)》2004,16(2):308-315
This paper assess the eco-environmental benefits that may come from the middle route project of China‘s South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT‘s middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13.07 billion RMB Yuan in 2010 and 19.79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors. 相似文献
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以125W高压汞灯为光源,研究了水中雌酮(E1)在铁(Ⅲ)-草酸盐体系中的光降解;考察了初始pH值、铁(Ⅲ)/草酸盐配比、E1初始浓度对E1光降解的影响。结果表明,铁(Ⅲ)/草酸盐体系能引发E1的光降解。在pH=3.5,Fe(Ⅲ)/Ox配比为10/120/zmol/L时,2mg/LE1光照160min可以降解59%。在pH3-6范围内,pH为3~4时E1降解效率最高;在2-10mg/L范围内,光降解效率随水溶液中E1初始浓度的增加而降低。 相似文献
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采用序批式反应器(SBR)处理模拟精对苯二甲酸(PTA)废水,考察了曝气量、沉降时间、进水方式等对对苯二甲酸(TA)生物降解效果的影响。实验结果表明,对于TA质量浓度小于1500mg/L的废水,采用完全曝气SBR运行4h,TA和COD的去除率均能达到95%以上,TA平均去除速率随TA浓度的增加而增大。TA质量浓度为1500mg/L时,曝气量、沉降时间和进水方式是影响其降解效果的主要因素。采用SBR处理高浓度PTA废水可克服污泥膨胀和抗冲击负荷能力弱的问题,且系统的稳定性和PTA废水的处理效果较好。 相似文献
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Du Yongsheng Guo Yuhang Wang Guangyu Zhang Hongxia Deng Leibo Chen Hua Zhao Ming 《Journal of Material Cycles and Waste Management》2023,25(5):3081-3092
Journal of Material Cycles and Waste Management - High-performance slag glass–ceramics were prepared by melting method using rare earth-containing blast furnace slag as the main raw material... 相似文献