排序方式: 共有58条查询结果,搜索用时 15 毫秒
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依据2010年度胶州湾围填海面积数据,通过构建胶州湾生态服务功能,对胶州湾围填海造地造成的海洋生态服务功能价值损失进行定量评估.结果表明,胶州湾填海造地造成的海洋生态系统服务功能价值损失总值为33 186.34万元/a.其中,供给功能价值损失最大(22 732.75万元/a),占总价值损失的68.50%;调节功能的价值损失次之,占总价值损失的18.89%;支持功能和文化功能价值损失所占比例最小. 相似文献
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沉积物中重金属区域环境背景的构建——以广西潮间带为例 总被引:2,自引:0,他引:2
基于2007年采自广西潮间带的?6?根短柱样,在沉积物粒度、有机碳、常量元素(Al、Fe和Ti)、重金属元素(Hg、Cu、Pb、Zn、Cd、Cr和As)以及?210Pb?分析的基础上,利用深层“清洁”沉积物中重金属与归一化元素间的线性回归构建了广西潮间带区域环境背景线。本文选用?Al?元素作为广西潮间带沉积物中的归一化元素。并借助于富集系数清晰展现了近期人类活动对广西潮间带沉积物的影响程度,这对研究广西乃至全国临海陆域人类活动的排污史有着重要借鉴意义。 相似文献
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为深入了解海岸带湿地景观演变过程和演变原因,对其进行有效保护和合理开发利用,以3个时期多光谱遥感影像和1个时期江苏省盐城市植被分布图为数据基础,结合现场调查数据,进行了研究区海岸带湿地景观演变分析并探讨了其变化的原因。研究结果表明:盐城海岸带湿地在近30a(1980-2008年)间,自然湿地(河口水域、盐蒿滩、芦苇沼泽、互花米草滩)的面积呈不断减小趋势,人工湿地(养殖水域、盐田)、建设用地和耕地面积则呈不断增长趋势,湿地景观演替方向总体上表现为自然湿地向人工湿地转移占主导,自然湿地之间的相互演替速度较缓慢,大面积自然湿地已消失且单个湿地景观斑块面积变小、形状趋于简单化,景观破碎化逐年加剧。造成这一结果的原因是人类活动与自然因素的综合作用,尤其是人口增长、经济利益驱使等,使人类对湿地的干扰力度不断增强,湿地围垦成为盐城海岸带湿地演变的主要原因。 相似文献
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近140年来广西红树林演变及其对人类活动的响应:有机碳和孢粉联合示踪 总被引:2,自引:1,他引:1
Mangrove degradation must reduce carbon sequestration in recent years, thereby aggravating global warming.Thus, short-term impacts of human activity on mangrove ecosystems are cause for concern from local governments and scientists. Mangroves sediments can provide detailed records of mangrove species variation in the last one hundred years, based on detailed 210 Pb data. The study traced the history of mangrove development and its response to environmental change over the last 140 years in two mangrove swamps of Guangxi, Southwest China. Average sedimentation rates were calculated to be 0.48 cm/a and 0.56 cm/a in the Yingluo Bay and the Maowei Sea, respectively. Chemical indicators(δ13Corg and C:N) were utilized to trace the contribution of mangrove-derived organic matter(MOM) using a ternary mixing model. Simultaneous use of mangrove pollen can help to supplement some of these limitations in diagenetic/overlap of isotopic signatures. We found that vertical distribution of MOM was consistent with mangrove pollen, which could provide similar information for tracing mangrove ecosystems. Therefore, mangrove development was reconstructed and divided into three stages: flourishing, degradation and re-flourishing/re-degradation period. The significant degradation, found in the period of 1968–1998 and 1907–2007 in the Yingluo Bay and the Maowei Sea, respectively, corresponding to a rapid increase of reclamation area and seawall length, rather than climate change as recorded in the region. 相似文献
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