Linking human-biophysical interactions with the trophic status of Dal Lake,Kashmir Himalaya,India     

《Limnologica》2017

The study analyses the long-term biophysical and demographic changes in Dal lake, located in the heart of Srinagar city, Kashmir India, using a repository of historical, remote sensing, socio-economic and water quality data supported by the extensive field observations. The lake faces multiple pressures from the unplanned urbanization, high population growth, nutrient load from intensive agriculture and tourism. The data showed that the lake has shrunk from 31 km² in 1859–24 km² in 2013. Significant changes were observed in the land use and land cover (LULC) within the lake (1859–2013) and in the vicinity of the lake (1962–2013). Analysis of the demographic data indicates that the human population within the lake has shown more than double the national growth rate. Additionally, 7 important water quality parameters from 82 well distributed sites across the lake were analyzed and compared with the past data to determine the historical changes in the water quality from 1971 to 2014. The changes in the LULC and demography have adversely affected the pollution status of this pristine lake. Ortho-phosphate phosphorous concentration has increased from 16.75 μg L⁻¹ in 1977–45.78 μg L⁻¹ in 2014 and that of the nitrate-nitrogen from 365 μg L⁻¹ to 557 μg L⁻¹, indicating nutrient enrichment of the lake over the years. Built-up area within the lake has increased 40 times since 1859, which, together with the changes in the population and settlements, have led to the high discharge of untreated nutrient-rich sewage into the lake. Similarly the expansion of floating gardens within the lake and agriculture lands in the catchment has contributed to the increased nutrient load into the lake due to the increasing use of fertilizers. The information about the existing land cover, demography and water quality was integrated and analyzed in GIS environment to identify the trophic status of the lake. The analysis indicated that 32% of the lake falls under sever degradation, 48% under medium degradation while as 20% of the lake waters are relatively clean. It is believed that the results provide improved knowledge and insights about the lake health and causal factors of its degradation necessary for effectively restoring its ecological and hydrological functionality.  相似文献   

Observational information on a temperate reef community helps understanding the marine climate and ecosystem shift of the 1980–90s     

Giulia Gatti  Carlo Nike Bianchi  Monica Montefalcone  Sara Venturini  Giovanni Diviacco  Carla Morri 《Marine pollution bulletin》2017,114(1):528-538

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Excess seawater nutrients,enlarged algal symbiont densities and bleaching sensitive reef locations: 2. A regional-scale predictive model for the Great Barrier Reef,Australia     

Scott A. Wooldridge  Scott F. Heron  Jon E. Brodie  Terence J. Done  Itsara Masiri  Saskia Hinrichs 《Marine pollution bulletin》2017,114(1):343-354

A spatial risk assessment model is developed for the Great Barrier Reef (GBR, Australia) that helps identify reef locations at higher or lower risk of coral bleaching in summer heat-wave conditions. The model confirms the considerable benefit of discriminating nutrient-enriched areas that contain corals with enlarged (suboptimal) symbiont densities for the purpose of identifying bleaching-sensitive reef locations. The benefit of the new system-level understanding is showcased in terms of: (i) improving early-warning forecasts of summer bleaching risk, (ii) explaining historical bleaching patterns, (iii) testing the bleaching-resistant quality of the current marine protected area (MPA) network (iv) identifying routinely monitored coral health attributes, such as the tissue energy reserves and skeletal growth characteristics (viz. density and extension rates) that correlate with bleaching resistant reef locations, and (v) targeting region-specific water quality improvement strategies that may increase reef-scale coral health and bleaching resistance.  相似文献   

岩溶地区生态系统养分平衡研究   总被引：7，自引：2，他引：5  

姚长宏  杨桂芳  蒋忠诚  袁道先 《中国岩溶》2001,20(1):41-46

以岩溶地区生态系统中养分储存和运移为中心,综合研究了矿物分化、大气降水而引起的养分输入,淋溶流失、水土流失造成的养分输出,以及与生物导致的养分内部循环之间的相互作用和相互联系;讨论了岩溶生态系统养分的流入、保持和流失之间的平衡,并以桂林丫吉村岩溶试验场为例建立系统内各养分体系之间的反馈网络模型。   相似文献   

地学信息图谱的研究及其模型应用探讨   总被引：8，自引：2，他引：6  

田永中  岳天祥 《地球信息科学学报》2003,5(3):103-106

地学信息图谱系以遥感与地理信息系统等新技术 ,充分发挥人脑的形象思维能力来解决资源环境问题。它是地学思维在新时代下的新发展 ,在地学研究中有重要的理论和实践意义。文章着重分析了地学信息图谱研究近况 ,并结合生态系统综合评估 ,论述了地学信息图谱在该领域的应用。  相似文献   

灵芝中外源性污染物分析及风险评估          下载免费PDF全文

陆才洋  匡创富  梁雪娟 《应用海洋学学报》2023,39(10):187

目的：研究湖南省不同地区灵芝中外源性污染物含量,并对其重金属及有害元素进行健康风险评估,以期为灵芝的质量检测提供依据。方法：按照2020年版《中华人民共和国药典》（简称《中国药典》）对灵芝中重金属及有害元素、农药及二氧化硫等外源性污染物含量进行测定,通过计算每日最大可耐受量（EDI）和靶标危害系数（THQ）对其中重金属及有害元素含量进行健康风险评估。结果：各批次灵芝中砷、镉、汞、铅的含量均符合《中国药典》的限量标准。仅1批灵芝中砷含量和3批灵芝中镉含量不符合相关食品标准。EDI结果未发现明显健康风险;THQ结果显示,1批灵芝存在潜在健康风险。农药及二氧化硫残留检测结果显示,6批灵芝中农药残留量不符合限量标准,1批灵芝二氧化硫残留量不符合食品限量标准。结论：灵芝作为食药物质,需要有效控制外源性污染物含量,并及时完善相关质量标准。  相似文献   

盐田生态系统的生物调控   总被引：2，自引：0，他引：2  

李岿然  白洁  李永祺  李淑霞 《海洋科学》1998,22(6):38-40

借助盐田生态系统结构分析的结果,提出了盐田生态系统生物调控的基本模式,给出了控制变量的控制水平。  相似文献   

贝类养殖对海湾生态系统的影响   总被引：1，自引：0，他引：1  

季如宝  毛兴华  朱明远 《海洋科学进展》1998,(1)

本文描述了海水养殖贝类生态的主要特点,重点讨论了高密度贝类生物沉降过程以及对浮游植物的摄食控制等过程的生态效应。通过文献综述和个例分析,论述了贝类养殖对海湾生态系统的影响。本研究对贝类养殖业持续发展及沿海环境的保护均具有重要意义,文中还就今后的研究及方法学提出了建议。  相似文献   

太湖鱼类产量、组成的变动规律及与环境的关系   总被引：30，自引：3，他引：27  

刘恩生  刘正文  陈伟民  陈开宁 《湖泊科学》2005,17(3):251-255

湖泊生态系统健康包含两个方面的内涵:满足人类社会合理要求的能力和湖泊生态系统自我维持与更新的能力.获知湖泊生态系统健康状况及其区域分异特征,对于湖泊管理具有重要意义.本文基于对太湖的野外调查,计算了表征湖泊生态系统健康的系统能、系统能结构、生态缓冲容量和湖泊营养状态指数.聚类分析结果表明,太湖不同湖区生态系统健康状况存在一定差异,东部湖区较好,西部湖区较差,呈现由东南部湖区向西北部湖区递减的趋势.该结果对进一步研究湖泊生态系统健康评价指标阈值具有重要的参考意义.  相似文献   

基于生态系统的海洋综合管理研究 ——以美国大沼泽湿地项目为例          下载免费PDF全文

褚晓琳  许春凤 《海洋开发与管理》2021,38(3):25-32

基于生态系统的海洋综合管理是海洋管理的新理念和新模式,其倡导从海洋生态系统角度开展环境资源保护,并以促进海洋生态系统与人类开发活动的协调可持续发展为终极目标。美国大沼泽湿地项目是基于生态系统的海洋综合管理的经典范例。基于生态系统的海洋综合管理的核心理念是将整个生态系统纳入海洋综合管理范畴,颠覆传统的单一对象保护理念,实现海洋生态保护与人类生存发展协调可持续。美国大沼泽湿地项目采用了基于生态系统的海洋综合管理理念,将整个大沼泽湿地视为一个整体生态系统,实现联邦政府、州政府和社会组织协作,合力促进大沼泽湿地的绿色生态可持续发展。美国大沼泽湿地项目全面贯彻基于生态系统的海洋综合管理理念,采用联合管理模式,重视水资源环境治理取得一定成效,但也暴露出管理模式有待改进、公众宣传参与不到位、区域间联系不紧密等问题。  相似文献