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41.
不同土地利用方式下的七里海湿地临界评价研究   总被引:2,自引:0,他引:2  
在"湿地临界"概念的基础上,定性分析了湿地利用与保护的平衡状态,探讨了不同利用方式下的湿地临界的研究步骤,并从基于耕地和河蟹养殖地两种土地利用方式入手,对七里海湿地临界进行了评价。研究表明,通过建立湿地临界模型,从经济效益评价和生态效益的评估入手,对湿地资源利用与保护进行临界分析,可以较好的反映湿地利用的临界状态;采用该方法,七里海湿地耕地利用的年净收益为9 5941.42元/hm2,净损耗为18 072.75元/hm2,临界效益(△B)值为77 868.67元/hm2;养殖河蟹的年净效益为21 622.68元/hm2,净损耗为2 0274元/hm2,△B值为1 348.68元/hm2,说明在目前的社会经济发展水平下,耕地和养殖河蟹两种利用方式尚未超出开发利用的临界准则,七里海湿地仍然具有开发潜力。  相似文献   
42.
Based on the observation of a complete hydrological year from June 2014 to May 2015, the temporal and spatial variations of the main inorganic nitrogen(MIN, referring to NO_3~--N, NO_2~--N, NH_4~+-N) in surface water and groundwater of the Li River and the Yuan River wetland succession zones are analyzed. The Li River and the Yuan River are located in agricultural and non-agricultural areas, and this study focus on the influence of surface water level and groundwater depth and precipitation on nitrogen pollution. The results show that NO_3~-N in surface water accounts for 70%-90% of MIN, but it does not exceed the limit of national drinking water surface water standard. Groundwater is seriously polluted by H_4~+-N. Based on the groundwater quality standard of H_4~+-N, the groundwater quality in the Li River exceeds Class III water standard throughout the year, and the exceeding months' proportion of Yuan River reaches 58.3%. Compared with the Yuan River, MIN in groundwater of the Li River shows significant temporal and spatial variations owing to the influence of agricultural fertilization. The correlation between the concentrations of MIN and surface water level is poor, while the fitting effect of quadratic correlation between H_4~+-N concentration and groundwater depth is the best(R~2=0.9384), NO_3~-N is the next(R~2=0.5128), NO_2~--N is the worst(R~2=0.2798). The equation of meteoric water line is δD =7.83δ~(18) O+12.21, indicating that both surface water and groundwater come from atmospheric precipitation. Surface infiltration is the main cause of groundwater H_4~+-N pollution. Rainfall infiltration in non-fertilization seasons reduces groundwater nitrogen pollution, while rainfall leaching farming and fertilization aggravate groundwater nitrogen pollution.  相似文献   
43.
银川市鸣翠湖湿地旅游资源评价   总被引:2,自引:0,他引:2  
鸣翠湖湿地公园旅游资源丰富、类型多样,笔者通过实地调查研究,运用定性和定量相结合的评价方法对旅游资源进行评价,分析其结果,提出了鸣翠湖生态公园的后续发展设想,为旅游部门提供科学依据和参考。  相似文献   
44.
As one of the few ecological wetlands in North China,Baiyangdian bears multiple important ecological functions,including ①adjusting the ecological balance of North China;②safeguarding the downstream areas,especially Tianjin City,the Beijing-Shanghai Railway and Huabei Oil Field;③serving as the reservoir for the North-to-South Water Diversion Project and the emergent use of water for Beijing;④conserving biodiversity.Wetland ecotourism is a scientific and wise use pattern for wetland resources,through which,a source of financing is provided for wetland conservation,economic alternatives are generated for local people to reduce overexploitation on wetland resources and the public awareness of environmental protection is enhanced.Since wetland ecotourism can benefit the co-existence between human and nature and promote social equity between people,it enjoys broad promise for popularization and implementation.The proactive cooperation and sound interaction between main stakeholders,and the wide participation of the community residents,will guarantee the sustainable development of wetland ecotourism.Based on the analysis of current status of participation and interactive relationships of the main stakeholders in Baiyangdian tourism,this article made an attempt to apply the theory of participatory development to the ecotourism initiatives of Baiyangdian wetland,discussed and brought forward the countermeasures to improve community participation in wetland ecotourism under the guidance of this theory.  相似文献   
45.
自然保护区是我国社会经济可持续发展赖以实现的重要自然基础,林业系统占了我国自然保护区的绝大多数。本文对林业系统内湿地类型的自然保护区的类别、级别、区域和面积进行了统计和分析,并根据存在的问题提出了针对性的解决对策。  相似文献   
46.
城市湖泊湿地是城市重要的生态基础,具有许多生态功能和社会服务功能。合理开发和利用湿地资源是确保城市可持续发展的重要前提。针对武汉月湖的水体污染问题,围绕城市受污染水体的生境改善、生态系统结构优化与系统稳定等问题,开展水生植物定植、湖滨人工湿地、藻类控制、受污染底泥修复等水质改善技术的研究,并相应建设示范工程对月湖湿地进行管理和生态恢复。  相似文献   
47.
基于层次分析法的洽川湿地生态旅游质量评价研究   总被引:2,自引:0,他引:2  
基于对洽川黄河湿地考察调研资料的统计分析,建立湿地生态旅游定量评价的指标体系和评价模型,运用层次分析法确定各评价指标权重,得出定量评价结果。并在对主要指标评价结果分析的基础上,提出改进洽川湿地生态旅游质量的建议和对策。  相似文献   
48.
本文通过对呼伦贝尔湿地保护存在的主要问题的论述,列举了呼伦贝尔市湿地保护存在的主要问题,提出了保护呼伦贝尔湿地的相应对策。  相似文献   
49.
南京市主要城市湿地的公众评价   总被引:2,自引:0,他引:2  
城市湿地是城市生态系统的重要组成部分,对改善城市环境发挥着多方面的重要作用。本研究调查了城市湿地使用者,即市民,对南京城市湿地的评价与期望,并在此基础上提出湿地建设的改进建议。结果表明市民对城市湿地总体满意度较高,但在水质状况、护岸类型和基础设施等方面仍需改进。本研究探索了将市民的意愿纳入城市湿地规划的方法,对于进一步提高城市湿地规划建设具有参考价值。  相似文献   
50.
This paper presents the first attempt to use environmental magnetism to quantify sediment provenance on a managed realignment (MR) site. MR is one technique for creating/restoring intertidal habitats and improving the standard of coastal flood protection. Monitoring of MR sites is essential for determining how successful they are at achieving these aims, and normally includes measurement of sedimentation rates through the use of accretion plates and sediment erosion tables (SETs). One limitation of this technique is that the provenance of sediment accreting on realigned surfaces cannot readily be quantified. Our results demonstrate that magnetics-based fingerprinting can successfully apportion sediment source contributions to created/restored coastal saltmarshes with an efficiency similar to that of existing un-mixing models applied to other habitats (82.87%). Analysis of mineral magnetic properties (χFD, IRMsoft and SIRM) demonstrated that the majority of sediment accreting on the Freiston Shore MR Site (Lincolnshire, UK) is derived from established saltmarshes seaward of the breached embankment. This indicates that the MR site may be growing at the expense of neighbouring saltmarshes—thereby undermining the habitat-creation objectives used to justify MR. It is recommended that future MR monitoring programmes consider the provenance of post-breach deposits to help identify any adverse impacts that wetland creation/restoration may have on existing habitats. Further testing of environmental magnetism in coastal saltmarshes and MR sites is necessary to validate wider use of the technique.  相似文献   
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