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21.
When individual cells of a multiple-cell treatment wetland are hydraulically connected, the wetland has a cell-network structure. The hydraulic performance of treatment wetlands is often characterized using tracer residence time distributions (RTDs) measured between the wetland inlet and outlet, such that the wetland is considered as a single hydraulic unit, regardless of the extent of networking between individual internal cells. This work extends the single hydraulic unit approach to enable the specification of moments and RTD parameters for individual cells, or clusters of cells, within the cell-network based on inert tracer tests with injection only at the network inlet. Hydraulic performance is quantified in terms of hydraulic efficiency and travel time dimensionless variance using both the method of moments and RTD modeling. Cell-network analysis was applied to a case study from the Orlando Easterly Wetland (OEW), demonstrating the improvement in hydraulic performance of individual wetland cells following wetland restoration activities. Furthermore, cell-network analysis indicated that the location of water quality sampling station locations within the cell network can significantly affect the accuracy of pollutant removal effectiveness estimation when the individual sample station RTD does not represent the hydraulic unit RTD. At the OEW, it was determined that historical nutrient removal effectiveness estimation may be underestimated for one area and overestimated for another, and recommendations were provided for sample station locations to minimize future performance estimation errors. 相似文献
22.
Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface water. Moreover, a higher rate of decomposition than primary production (photosynthesis) may lead to a shift of their function from being a sink of carbon to a source. This review paper assesses the potential response of natural wetlands (peatlands) and constructed wetlands to climate change in terms of gas emission and nutrients release. In addition, the impact of key climatic factors such as temperature and water availability on wetlands has been reviewed. The authors identified the methodological gaps and weaknesses in the literature and then introduced a new framework for conducting a comprehensive mesocosm experiment to address the existing gaps in literature to support future climate change research on wetland ecosystems. In the future, higher temperatures resulting in drought might shift the role of both constructed wetland and peatland from a sink to a source of carbon. However, higher temperatures accompanied by more precipitation can promote photosynthesis to a degree that might exceed the respiration and maintain the carbon sink role of the wetland. There might be a critical water level at which the wetland can preserve most of its services. In order to find that level, a study of the key factors of climate change and their interactions using an appropriate experimental method is necessary. Some contradictory results of past experiments can be associated with different methodologies, designs, time periods, climates, and natural variability. Hence a long-term simulation of climate change for wetlands according to the proposed framework is recommended. This framework provides relatively more accurate and realistic simulations, valid comparative results, comprehensive understanding and supports coordination between researchers. This can help to find a sustainable management strategy for wetlands to be resilient to climate change. 相似文献
23.
基于我国对湿地的认知变化及保护历程,结合第二次全国湿地普查结果,分析当前我国湿地保护中存在的主要问题,并提出针对性建议,主要包括:落实保护红线、创新保护格局;完善法律法规、推进湿地保护绩效考核;实施生态补偿机制、提升湿地造血功能;加强科技支撑及人才建设、建立智能管理体系;宣扬湿地文化,推进社会主流生态价值观形成等。 相似文献
24.
近5年来,在林业部门的大力支持下,对玫瑰湖湿地进行重新规划,并在合理利用区实施了一系列的开发建设和保护保育管理工程,使水系得到疏通,水质逐步得到净化,生态环境及动植物栖息地得到很好的恢复与保护,同时也为人们提供了一处休憩游玩的好地方,探索出一条"建管结合"的湿地生态管理模式。 相似文献
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Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface water. Moreover, a higher rate of decomposition than primary production (photosynthesis) may lead to a shift of their function from being a sink of carbon to a source. This review paper assesses the potential response of natural wetlands (peatlands) and constructed wetlands to climate change in terms of gas emission and nutrients release. In addition, the impact of key climatic factors such as temperature and water availability on wetlands has been reviewed. The authors identified the methodological gaps and weaknesses in the literature and then introduced a new framework for conducting a comprehensive mesocosm experiment to address the existing gaps in literature to support future climate change research on wetland ecosystems. In the future, higher temperatures resulting in drought might shift the role of both constructed wetland and peatland from a sink to a source of carbon. However, higher temperatures accompanied by more precipitation can promote photosynthesis to a degree that might exceed the respiration and maintain the carbon sink role of the wetland. There might be a critical water level at which the wetland can preserve most of its services. In order to find that level, a study of the key factors of climate change and their interactions using an appropriate experimental method is necessary. Some contradictory results of past experiments can be associated with different methodologies, designs, time periods, climates, and natural variability. Hence a long-term simulation of climate change for wetlands according to the proposed framework is recommended. This framework provides relatively more accurate and realistic simulations, valid comparative results, comprehensive understanding and supports coordination between researchers. This can help to find a sustainable management strategy for wetlands to be resilient to climate change. 相似文献
30.
以西昌邛海国家湿地公园为例,采用半结构访谈与参与式制图相结合的方法对当地居民进行调查。通过质性+空间的混合分析方法探讨了居民感知冲突的类型、空间响应分布及其形成机制,旨在为自然保护地的冲突管理提供参考,实现人地关系协调发展。结果显示：① 社区居民感知有7种冲突类型,分别为生计保障不足、活动空间压缩、政策措施缺位、情感支持弱化、日常生活不便、环境质量降低和生产经营矛盾,前5种冲突总占比达76.4%,构成了当地的主要冲突;② 冲突的空间响应是居民对冲突关注度和不满意程度的共同反映,总体上呈现出高值区相对独立、低值区连片分布的空间格局,响应水平较高的区域,具有较高的冲突显示度和管理优先等级;③ 冲突的空间响应是多因素共同作用的复杂现象,其中旅游开发程度和生计策略的影响较大,交通出行管理、居住区类型、土地利用类型和房屋修建管理的影响也不容忽视,总体反映了邛海生态建设、旅游开发、政策与制度安排、社会经济等基本情况,分别为冲突响应提供了原始动力、外部推动力、结构性动力和社会性动力。 相似文献