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941.
中国热带气旋灾害及全球变暖背景下的可能趋势分析 总被引:9,自引:3,他引:9
在分析中国热带气旋灾害影响及时空分布的基础上,计算得出近40年西北太平洋年平均热带气旋发生总数和其中台风发生数与海表温度,以及与年平均登陆中国热带气旋总数和其中台风登陆数长趋势变化之间的相互关系,并据此估算了全球变暖后中国热带气旋灾害的可能变化趋势。结果表明,若至2050年前后全球变暖引起西北太平洋海表温度升高1℃,则在中国登陆热带气旋总数年平均将比现状增加65%,其中年平均登陆台风数将可能增加58%左右。 相似文献
942.
本文从资源环境超载、生态环境本底脆弱、水资源指标性短缺等方面对黄河流域煤化工产业发展的长期形势作出判断研究,系统梳理了煤化工产业发展的环境保护经验与教训,对煤化工产业发展中规模增长过快、布局不合理以及突出环保问题等经验和教训进行分析和评述。在此基础上,本文就黄河中上游煤化工产业高质量发展提出了若干建议,包括以生态环境安全格局稳定为原则,推动国家级煤化工相关专项规划编制及规划环评工作;转变传统发展模式,跨区域共建黄河中上游地区现代煤化工绿色技术创新平台;围绕再生水资源利用,推进煤化工“近零排放”和水权交易;按工业绿色发展理念和生态工业模式,促进煤化工产业优化升级等。 相似文献
943.
包怡斐 《中国人口.资源与环境》1997,7(2):57-60
本文用可持续发展观对引黄济青工程再评估后认为:水利建设和环境措施同步进行是引黄济青工程取得成功的关键。 相似文献
944.
可持续发展下的黄河水资源管理 总被引:1,自引:0,他引:1
唐伟群 《中国人口.资源与环境》2005,15(2):89-93
用可持续发展理论为指导。综合运用经济、环境、哲学、生态、水文等多学科知识。全面分析建国后黄河水资源管理中的制度缺陷。进而提出在可持续发展下的黄河水资源管理制度的新思路。文中在分析黄河水权、水价、水权交易的基础上。认为黄河漉域管理应是一个综合性、多中心、全面的管理模式.强调了漉域管理是一种集体行动。其中制度的作用尤为重要。 相似文献
945.
论我国水系网络化建设——兼论新世纪人民治黄的创新思路 总被引:1,自引:0,他引:1
李殿魁 《中国人口.资源与环境》2001,11(4):28-32
本文指出,发挥自然地理优势,实现大江大河的网络化,是我国水利建设的总目标,而实现这个目标,科学治理黄河,积极推进水系网络化进程,决策南水北调,成为当务之急。 相似文献
946.
Mamdouh Fahmy 《Chemistry and Ecology》2003,19(1):67-77
In order to provide a background picture of the water quality of the Egyptian Red Sea a number of hydrological and chemical parameters have been measured bimonthly in 2000. Few data are available on this area, which is apparently subjected to an increasing human impact due to recreational (swimming and diving), industrial (mainly phosphate shipping and industry) and fishing/harbor activities. The results of the present study indicate that changes in the salinity and pH were not significant with highly oxygenated seawaters. The levels of suspended solids (as total suspended matter, TSM) and chlorophyll-a (Chl-a) were generally low and showed an homogeneous distribution in the study region. The ratio of chlorophyll-a to total suspended matter concentrations increased between November and March and decreased from May to September. Chlorophyll-a was significantly correlated with transparency and total suspended matter concentrations in July, September and November. Nitrogen, phosphorus and reactive silicate concentrations were generally low, and allowed classifying the Egyptian Red Sea coastal water as oligotrophic to mesotrophic. The middle region of the study area, which was located between Safaga and Qusair displayed relatively high phosphate contents when compared with other coastal areas. The high values of N:P ratios indicate that PO 4 -P is the limiting factor for phytoplankton growth in the Red Sea coastal waters, with the possible exception of the middle region. Significant relationships were found between chlorophyll-a concentrations and nutrient levels in different sampling periods. Spatial distribution patterns of the studied variables revealed that productivity of the Red Sea coastal waters is mostly controlled by phosphate concentrations, salinity, temperature and dissolved oxygen. 相似文献
947.
Recent studies have identified the need to adapt to climate change by allowing landforms and habitats to migrate landward, although implementation of actual adaptation responses is limited. Removing the barriers that shore protection structures create between coastal and upland habitats can reestablish exchanges of sediment and the ecological functions of the natural ecotone. The potential for removing these structures was evaluated in 12 national parks managed by the U.S. National Park Service. Criteria for removal included condition of structures, influence of natural processes, environmental benefits, public safety, and visitor access and use.We found that 145 structures out of a total of 407 could be removed or allowed to deteriorate. We highlight three adaptation projects that are currently being conducted, two of which involve removing structures. Reasons for not taking a more pro-active approach to removing protection structures include (1) conflicting policy directives; (2) presence of key access roads and critical archaeological and historic sites; (3) lack of data; (4) lack of funds and human resources; (5) reluctance to replace known problems with an unknown set of problems; (6) consideration of visitor desires; and (7) reluctance to allow erosion to occur. Demonstration projects are needed to provide information about adaptation strategies that promote enhancement of ecosystem functions. Projects to remove protection structures are likely to be viewed as successful only if results are specified as a positive product, and the distinction between the concept of loss (erosion of existing landforms and habitats) and the concept of gain (evolution of new landforms and habitats) is made clear. 相似文献
948.
This work focuses on four marine sites of the Mediterranean Sea, north of the Nile Delta, Egypt. Surface-water samples were collected seasonally during 2003. The aim of this study is to assess the levels of some dissolved trace metals (Fe, Mn, Zn, Cu, and Pb) in two environmental conditions. The metal concentrations in the coastal zone were in the following ranges: 11.92-30.45 μg l-1 for Fe, 5.79-17.36 μg l-1 for Mn, 0.87-7.80 μg l-1 for Zn, 0.40-1.87 μg l-1 for Cu, and 1.53-10.31 μg l-1 for Pb. In the sites with continental water input (mixing zone), the metals were scattered in the following ranges: Fe (19.72-60.33 μg l-1), Mn (12.63-35.60 μg l-1), Zn (2.67-22.00), Cu (0.83-8.10 μg l-1), and Pb (1.72-29.7 μg l-1). The results for the metal concentrations showed a remarkable decrease in the levels of the different metals going from the estuaries and outlets into the coastal sea water. Generally, the levels of the metals in the two zones are higher than the background levels of the unpolluted area. A comparison of the trace-metal levels in the coastal zone of the Mediterranean Sea north of Nile Delta with the minimal risk concentration (reported by water-quality criteria, WQC) showed a significantly lower content at the coastal area of the Mediterranean sea of Egypt. The study also indicated that the impact of anthropogenic inputs was limited in the distribution of the metals, except that the Pb content was slightly higher in the area of the mixing zone than that reported for WQC. The relationships between the different trace-metal concentrations and the other parameters (salinity, chlorophyll a and suspended particulate matter) were discussed, and the simple regressions between them were evaluated. 相似文献
949.
To examine whether U.S. public opinion may become as sharply polarized on adaptation responses as it has been on mitigation policies, we surveyed a sample of urban coastal residents in Maryland (n = 378). We then tested the impact of a community deliberative event (n = 40) with small-group sea level rise discussions as a depolarization strategy. Cultural worldviews which contribute to politically polarized beliefs about climate were predictive of perceptions of sea level rise risk. Living close to flooding hazards also significantly predicted respondents’ perceptions of household or neighborhood risks, but not of risks to the entire county. The event significantly increased topic knowledge among all participants and, among those with a worldview predisposing them to lower risk perceptions, significantly increased problem identification and concern about impacts. These results suggest small-group deliberation focused on local problem-solving may be an effective tool for reducing the polarizing effects of cultural worldviews on decision-making. 相似文献
950.
黄河小浪底水库水沙调控对DOC输送的影响 总被引:1,自引:1,他引:0
于2011年11月至2012年10月在黄河中游的三门峡、小浪底和花园口3个水文站进行每月1次的周期性采样观测以及在调水调沙期间进行连续采样观测,分析了小浪底水库水沙调控对溶解有机碳(DOC)输送的影响.结果表明,在小浪底水库和三门峡水库正常调度期间,三门峡站、小浪底站和花园口站的DOC含量分别为1.97~2.71 mg·L-1、1.87~2.76 mg·L-1和2.07~2.93 mg·L-1,并且均有明显的季节变化;在调水调沙期间,三门峡站、小浪底站和花园口站的DOC含量分别为2.14~3.32 mg·L-1、2.21~2.84 mg·L-1和2.11~2.84 mg·L-1,并且水库排沙阶段的DOC含量明显高于水库泄水阶段的DOC含量.无论是在水库正常调度期间还是在调水调沙期间,DOC含量与TSS含量及流量均没有表现出显著的相关性,而在水库正常调度期间DOC含量与水温呈现显著的正相关关系.11月~次年3月三门峡站和小浪底站的DOC输送量比较接近,4~7月三门峡的DOC输送量明显低于小浪底站,而8~10月三门峡站的DOC输送量又明显高于小浪底站,表明小浪底水库在8~10月大量拦蓄DOC,而在4~7月又将拦蓄下来的DOC排出水库.三门峡站、小浪底站和花园口站DOC年输送量分别为8.6×1010、9.0×1010和9.7×1010g,其中三门峡站9月DOC输送量最多,约占全年DOC输送量的22.0%,小浪底站6月DOC输送量最多,约占全年DOC输送量的17.6%,花园口站7月DOC输送量最多,约占全年DOC输送量的16.7%.在2012年调水调沙期间小浪底站和花园口站的DOC输送量占全年DOC输送量的比例分别为14.7%和13.8%,而三门峡站DOC输送量仅占全年DOC输送量的3.6%. 相似文献