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11.
参考地表水环境质量标准和湖库营养状态评价标准,采用基于遗传算法的投影寻踪模型,计算反映湿地水体质量状况和湿地营养状态的一维投影值,直观地反映湿地水环境质量。将此方法在河北衡水湖湿地进行了实例应用,结果表明,衡水湖湿地2010年水质属于Ⅱ类,处于中度富营养状态。 相似文献
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This paper presents a theoretical analysis of a pulsed bicomponent contaminant emission into a free-surface wetland flow.The basic equations are for the bicomponent contaminant transport in the wetland flow under the combined action of advection,mass dispersion,and ecological reaction at the phase averaged scale.The effect of the ecological reaction is separated from the hydro-dynamic effect via a set of widely used transforms.The analytical solution for the evolution of the depth-averaged concentration is rigorously derived,with a limiting case covering the known solution for the single component contaminant transport.It is found that the depth-averaged species concentration of the bicomponent contaminant can approach an equilibrium state determined by the distri-bution coefficient. 相似文献
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生态需水量的核算是湿地水文生态恢复的关键步骤。通过分析计算,评估天津滨海新区湿地生态系统各类生态需水的3个特征值:最低生态需水量(即湿地生态系统丧失生态功能的临界需水量)、最适生态需水量(即维持湿地生态功能最佳状态的需水量)、最高生态需水量(即湿地生态系统所能承受的最大水量),得出如下结论:天津滨海地区湿地的生态需水主要包括蒸发蒸散需水量、湿地土壤需水量、补给地下水、湿地生物栖息地需水量4个部分;湿地的最低生态需水量为177.68×106~276.85×106 m3,最适生态需水量539.23×106~807.81×106 m3,最高生态需水量1 206.55×106~1 409.02×106 m3。 相似文献
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North America has few cultural agricultural landscapes, and often commensurately poor governance arrangements for managing change in such settings. This research uses the Acadian dykelands of Nova Scotia, Canada, as an opportunity to explore the social and governance limits to coastal climate adaptation in ‘new world’ cultural agricultural landscapes, as well as inform local decision-making. Approximately half of Nova Scotia’s coastal wetlands were converted to dykeland in the 1600s, lowering local resilience to the increased frequency and storm severity anticipated with climate change. Today, dykelands protect a diversity of public and private interests, meanings and values, yet are controlled by the agricultural sector, which can no longer afford to maintain them all to 2050 climate projections. We report here on a representative online Q-methodology survey of 183 adult Nova Scotians in the spring of 2015. Respondents sorted 34 statements along a normal distribution about whether they prefer dykeland maintenance or wetland restoration, and under what governance arrangements. Four factors were derived: the dominant discourse was local, female and strongly pro-dykeland, indicating the likelihood for local resistance to dykeland removal on for cultural, recreational and farming reasons. The second factor was supportive of wetland restoration for reasons of efficiency, not wetland affinity, but characterized by those in positions of management power. The two minority viewpoints were less informed about dykelands, characteristic of outsiders, and concerned more with governance. More education is needed about the challenges facing dykelands, the benefits of coastal wetlands, and the management options, but this research shows proposals to change landscape should emphasize flood mitigation over cost-saving. Cultural values and status quo bias are clearly barriers to adaptation planning, even when discussing the removal of man-made structures. The factors were surprisingly polarized, suggesting the forced-normal distribution affects the space available to convey nuanced perspectives. Large p-set Q-method of this kind is likely most useful for characterizing the emergent discourses demographically, and understanding their prevalence; the same discourses had emerged within a much smaller pilot study. 相似文献
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从湿地类型、面积及其比例构成等方面介绍了吉林省柳河县湿地资源现状与基本特征;分析了湿地面积的动态变化及其原因;探讨了涅地资源变化特点及其未来发展趋势.认为湿地资源的利用率和生产力较低、湿地自然保护区建设缓慢以及泥炭地开发利用过度等方面,是目前柳河县湿地利用与保护中所存在的主要问题;在此基础上,提出实施柳河县湿地生态保护... 相似文献
17.
采用实地调查和实验分析,结合遥感和地理信息系统技术,研究南四湖湿地在1983-2006年浮游植物和水生维管束植物的种类、分布和生物量变化.结果表明,1983-2006年,南四湖湿地植被生物量整体呈下降趋势,反映了人类的围垦、养殖等活动造成湿地初级生产力的降低,并且这种影响由湖泊外围向湖心弱化,对外围湿地的影响最大. 相似文献
18.
长沙市湿地资源类型及其特征研究 总被引:2,自引:0,他引:2
长沙市湿地包括永久性河流,淡水湖泊,草本沼泽等自然湿地类型;水库、拦河坝、水电坝,淡水养殖池塘,农用池塘、小型水池,废水处理场所,城市景观水面和娱乐水面,灌溉用沟、渠等人工湿地类型.长沙市湿地生态系统不仅为长沙地区提供了大量的生产生活用水和动植物产品等多种资源,同时还是诸多野生动植物的重要栖息地,湿地对于珍稀濒危物种的... 相似文献
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Understanding spatial patterns of visitation and benefits accrued to different types of natural and cultural heritage tourists may have important implications for the sustainable management of their destinations. We investigate cultural services accrued to local, domestic and international visitors to the Usumacinta floodplain, a coastal region with one of the highest biological and cultural diversities in Mexico. We combine analysis of social media photographs and high-resolution land cover mapping to identify different cultural services and their association with specific ecosystem and land cover types. Hotspots for international tourists are spatially restricted to well-known and accessible sites. Locals are 2.2–2.5 times more likely than international visitors to be associated with aesthetic appreciation and birdwatching. Locals upload more photographs of coastal lagoons, mangroves, beach and sea. Results are analyzed in light of land cover changes in the region and provide valuable information to decision makers for improved tourism management and conservation strategies. 相似文献