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中美国家重点风景名胜资源管理体制若干问题探讨 总被引:5,自引:1,他引:5
费宝仓 《地理与地理信息科学》2003,19(6):89-92
近来,有许多关于国家重点风景名胜区主要景点的经营权转让问题的讨论,主要围绕保护资金和私人企业对国家重要风景名胜资源保护与管理的可行性,笔者认为深层次的问题在于管理体制。研究美国国家公园体系管理体制,分别从组织管理、法治和资金来源角度与我国国家重点风景名胜区管理体制进行比较,并提出改进建议。 相似文献
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对我国湿地保护问题的思考 总被引:15,自引:8,他引:15
我国湿地正面临着来自人类的巨大威胁,生存型扩张的压力依然没有减轻,发展型扩张又严重威胁着湿地,导致自然湿地数量继续减少、湿地生态功能退化乃至丧失,已难以满足保障国家生态安全的需求。根据经济发展和人口、资源现状,我国的湿地战略应当是有限目标的国家战略。在湿地保护与合理利用总目标下,近期国家湿地战略以湿地保护为重点,即以保护自然(原生)湿地为主,对退化湿地进行生态恢复、重建和合理利用的示范为辅。 相似文献
505.
R Kerry Turner Stavros Georgiou Roy Brouwer Ian J Bateman I J Langford 《The Geographical journal》2003,169(2):99-116
This paper develops a decision support system for evaluation of wetland ecosystem management strategy and examines its, so far partial, application in a case study of an important complex coastal wetland known as the Norfolk and Suffolk Broads, in the east of England, UK. Most managed ecosystems are complex and often poorly understood hierarchically organized systems. Capturing the range of relevant impacts on natural and human systems under different management options will be a formidable challenge. Biodiversity has a hierarchical structure which ranges from the ecosystem and landscape level, through the community level and down to the population and genetic level. There is a need to develop methodologies for the practicable detection of ecosystem change, as well as the evaluation of different ecological functions. What is also required is a set of indicators (environmental, social and economic) which facilitate the detection of change in ecosystems suffering stress and shock and highlight possible drivers of the change process. A hierarchical classification of ecological indicators of sustainability would need to take into account existing interactions between different organization levels, from species to ecosystems. Effects of environmental stress are expressed in different ways at different levels of biological organization and effects at one level can be expected to impact other levels, often in unpredictable ways. The management strategy, evaluation methodologies and indicators adopted should also assess on sustainability grounds whether any given management option is supporting, or reducing, the diversity of functions which are providing stakeholders with the welfare benefits they require. 相似文献
506.
虎林市境内湿地与干地气候因子相关分析 总被引:4,自引:0,他引:4
以20多年观测数据为基本资料,对虎林市境内干地与湿地气候因子进行相关分析,说明大量的湿地开发对区域小气候影响明显。 相似文献
507.
Wetland parks play various ecological roles, including maintaining regional ecological balance, and connoting and compensating water sources. Taking Harbin Qunli National Urban Wetland Park as the research object, the diversity of plant resources in wetland parks is investigated and analyzed with the goal of providing a scientific basis for ecological restoration and the conservation and utilization of urban wetlands. Field survey, sampling and data collection methods were used to study the wetland plant resources and their life types (e.g., vines or shrubs), ecological types and distribution types. The study found 60 families, 129 genera and 160 species of wetland plants in Qunli National Urban Wetland Park, including 56 families, 123 genera and 151 species of angiosperms, which include 48 families, 101 genera and 127 species of dicotyledons and 8 families, 22 genera and 24 species of monocotyledons; 2 families, 2 genera and 3 species of ferns; and 2 families, 4 genera and 6 species of gymnosperms. The family composition is dominated by those families that included 10 or more species, and the dominant families are Compositae and Rosaceae. The genus composition is dominated by genera with four or more species present, and the dominant genera are Acer, Malus and Artemisia. Among the six life types, herbaceous plants are dominant, with a proportion of 62.50% of the species. The ecological types are divided into three categories: wet, mesophytic and aquatic plants, with wet plants accounting for the largest proportion, i.e., 56.25% of the total number of plant species. There are five distribution types of plant families and 10 types of the genera, with both families and genera dominated by the Northern Temperate types, so the flora has obvious temperate characteristics. 相似文献
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利用涡度相关法研究青海湖高寒湿地生态系统2015-2016年生长季CH4通量。结果显示:生长季CH4通量表现为白天排放、夜间微弱吸收或排放的日变化特征,其中2015年CH4通量日平均值为56.67 mg·m-2,2016年CH4通量日平均值为35.92 mg·m-2。7月和8月排放量最大,生长季前期和后期排放较弱,2015年最大排放量出现在7月,为3.76 g·m-2,2016最大排放量出现在8月,为1.67 g·m-2。温度、电导率、土壤体积含水量与CH4通量显著相关,气温和CH4通量线性正相关。生态系统总初级生产力和呼吸及水热通量与CH4通量也存在显著的相关关系,其中生态系统总初级生产力和呼吸是影响甲烷动态变化的主要因子。 相似文献
510.
为深入认识鄱阳湖湿地区域水循环过程,于2019年1—12月在鄱阳湖国家级自然保护区对降水、河流水、主要碟形湖水进行系统采集,综合分析碟形湖-河流水稳定同位素的动态变化特征及其指示意义。结果表明,鄱阳湖湿地修河和赣江的同位素组成具有明显的季节性变化规律,4月河水同位素最为富集,5—7月逐渐贫化,之后呈现出不断富集的变化趋势,整体上与降水同位素的时间变化特性相似。在空间分布上,各段河水的同位素组成均具有相对稳定的沿程分布特征,赣江在修河汇入点上、下游的同位素特性在大多数月份没有呈现出明显变化。碟形湖水同位素的年内变化范围比河水大,并且相对富集。主要碟形湖水的δ2H-δ18O关系接近当地大气降水线,具有更小的蒸发线斜率以及系统性偏离的特征,反映碟形湖主要受到当地降水补给,经历了一定程度的蒸发作用。基于指数模型方法估算修河和赣江水体的平均滞留时间(mean residence time,MRT)分别为1.54和0.81年,赣江较短的MRT表明鄱阳湖流域具有不同水体组分相互快速转化的水力条件,修河上游柘林水库的调蓄作用导致其MRT明显大于赣江。通过假定... 相似文献