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衡水湖湿地生态系统调节功能的价值估算 总被引：1，自引：1，他引：0
根据千年生态系统评估（MA）对生态系统服务功能的分类,运用生态经济学中的市场价值法、影子工程法、碳税法等方法,对衡水湖湿地生态系统的调节功能的价值进行评估．调节功能的总价值为41．58亿元．由于基础资料获得的局限性,该研究的结果比实际要偏低,但这个数据依然清楚地说明了衡水湖湿地在区域可持续发展中的巨大作用． 相似文献
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衡水湖湿地是国家级自然保护区,位于华北平原中南部的衡水市境内,面积268.34 km2.根据衡水湖的国民经济统计资料、总体规划、生态环境监测资料等,运用市场价值法、费用支出法、影子工程法、碳税法、机会成本法、成果参照法等生态经济学方法,初步估算出衡水湖生态系统的综合价值为45.25亿元,其中供给功能为0.53亿元,调节功能为41.58亿元,文化功能为1.96亿元,支持功能为1.18亿元.并且对各项指标进行了分析比较.由于基础资料获得的局限性,该研究的结果比实际要偏低,但这个数据依然清楚地说明了衡水湖湿地在区域可持续发展中的巨大作用. 相似文献
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衡水湖湿地是华北地区重要的自然资源,生物多样性丰富.通过对衡水湖湿地的植物、鸟类资源、人类活动等进行调查,运用指标法对衡水湖的生物多样性现状进行了评价分析.结果表明：衡水湖湿地的生物多样性较好;而评价指标中＂人类威胁＂指标分值偏低,意味着在高强度人类活动的作用下,水体富营养化程度加深,整体生态系统正在退化.在此基础之上,提出了衡水湿地生物多样性的保护对策. 相似文献
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大庆湿地具有重要的生态系统服务功能,大庆湿地在大庆城市发展和生态环境保护中起着重要作用。进行湿地生态系统服务功能评估,以货币价值的形式表达湿地生态系统服务能力,有助于湿地资源的保护和提高公众对湿地生态系统服务的认知,保护湿地生态环境。经对大庆湿地造地价值、物质生产价值、供给水源功能价值、重要物种栖息地功能价值、净化功能价值、教育科研旅游价值等生态系统服务功能进行分析,得出湿地生态系统服务功能价值总量为108创．53亿元。加强湿地资源的可持续发展研究,将对大庆城市转型发展发挥极为重要的作用。 相似文献
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根据环境经济学和生态经济学的估算方法,将大庆湿地主导生态系统服务功能的价值进行量化,对研究区湿地生态系统服务功能价值总量进行分析,得出研究区湿地生态系统服务功能价值总和为63.14亿元。其中,物质生产功能价值为0.81亿元,大气组分调节功能价值、供给水源功能价值、蓄水调洪功能价值和美学旅游功能价值分别为9.20、2.92、24.45和7.48亿元,其他功能价值为18.28亿元。自然湿地的生态系统服务功能主要体现在蓄水调洪功能和净化水质功能上,而人工湿地的生态服务功能主要体现在蓄水调洪和供给水源上,水库沟渠为其主要的贡献者。自然湿地的生态系统服务价值远远大于人工湿地,自然湿地对经济发展起着极为重要的作用。 相似文献
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衡水湖湿地植物群落初探 总被引：7，自引：0，他引：7
衡水湖湿地植物群落包括：水生植物群落、湿地滩涂植物群落及陆生植物群落。这些不同的植物群落都有它们常见的代表植物。这些不同类型的植物群落，反映了衡水湖对维护华北平原内陆湿地生态系统的典型性、稀有性及重要性功能，具有非常重要的意义。 相似文献
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湿地修复具有保护生物多样性、净化水体、调节小气候等多重作用,但近年来由于大气污染、水源污染等影响使得衡水湖湿地生态系统受到严重威胁。对衡水湖滨水带进行实地调研发现,湿地公园和荷花园的规划建设迫切需要对湿地滨水景观进行生态修复,植物景观仍然存在道路与服务设施系统不够完善、驳岸形式过于单一等问题。衡水湖湿地公园景观设计应基于生态修复理念,遵循保护优先、分区保护原则,以生境保护为核心,通过构建生态廊道、丰富植物景观、改善生态布局、建立监测系统等措施优化衡水湖滨水景观。 相似文献
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衡水湖污染现状及防治对策 总被引：1，自引：0，他引：1
衡水湖是华北平原上惟一保持沼泽、水域、滩涂、草甸和森林等完整湿地生态系统的自然保护区,近年来随着周边工业企业及生活污水排入湖内,造成水质富营养化,污染严重．为保护湖区,应采取措施加大污染综合治理力度,改善衡水湖水质,使衡水湖自然生态环境得到有效保护． 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献