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The status of the ecological environment and a proposed protection strategy in Sanya Bay,Hainan Island,China 总被引:8,自引:0,他引:8
Huang L Tan Y Song X Huang X Wang H Zhang S Dong J Chen R 《Marine pollution bulletin》2003,47(1-6):180-186
Sanya Bay encompasses a high diversity of natural habitats, ranging from coral reefs, rocky and sandy shores and mudflats to mangroves. Seasonal physicochemical and biological investigations were conducted from 1998 to 1999 and again in April 2000. Water-related environmental quality in Sanya Bay is in good condition. The levels of dissolved oxygen, nitrogen, phosphorus and heavy metals are within the first class of National Seawater Quality Standards for China. Annual mean values of chlorophyll a of 0.93 mg m(-3) and phytoplankton primary productivity of 440.8 mgC m(-2)d(-1), respectively, were found in the waters, both of which show a significant correlation with inorganic nitrogen. A mean new productivity of 144.6 mgC m(-2) d(-1) was recorded in summer. Sanya Bay is rich in natural resources and biodiversity with 235 species of phytoplankton and 129 species of zooplankton identified in the survey. The annual mean abundance of phytoplankton and zooplankton were 1564 x 10 cells m(-3) and 121 individuals m(-3), respectively, with an annual mean zooplankton biomass of 129 mg m(-3). A total of 243 species of fish were sampled in the survey including many of high economic value. Three hundred and eighty-four species of benthos in 121 families were found by mud sampling and trawling. The average biomass of benthic organisms was 11.55 gm(-2), with a density of 31 individuals m(-2). Molluscs were the dominant group, followed by crustaceans; coelenterates exhibited the lowest biomass. One hundred and twenty-six species from 48 families of intertidal organisms were collected by frame sampling, with a mean annual biomass of 644.7 gm(-2) and average density of 816 individuals m(-2). The highest biomass of 1673.5 gm(-2) was collected in a coral reef region, while the highest density of 1219 individuals m(-2) occurred in a mangrove region. The coastline is characterized by coral reefs that accounts for 30% of the total coastline length in the bay, so coral reefs are a key ecosystem that are important for maintaining the regional marine resources and biodiversity. We need to pay much more attention to such diverse marine resources to maintain the integrity and function of these coastal ecosystems. 相似文献
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断陷湖盆隐蔽油藏预测及勘探的关键技术--高精度地震探测基础上的层序地层学研究 总被引:82,自引:6,他引:76
近十余年世界的我国隐蔽油藏勘探取得了巨大进展,其关键技术是高精度的三维地震及在此基础上的层序地层学研究,二者的结合已被油气产业部门当作勘探中的“权威性技术”。断陷湖盆在我国东部含油气资源的重要性居首位,控制层序形成演化的诸因素中,构造,古气候和在区域古地理格局中的位置对湖盆的类型和演化起着决定作用,需要按照断陷湖盆的沉积构造演化特征建立有预测功能的层序构成模式,在成熟的勘探区,重新建立等时层序地层格架,进行体系域精度的工业制图,阐明沉积体系的分布规律,使用高精度地球物理技术对圈闭定位,并对构造坡折带和低位域扇体给予重点注意,用这种技术方法指导隐蔽油气藏的勘探,已经并必将有许多重要发现。 相似文献
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Sung-Soo Cha Kang-Kun Lee Gwang-Ok Bae Dae-Hyuck Lee Nicolas Gatelier 《Engineering Geology》2007,93(3-4):117-129
Hydrogeological monitoring was conducted around a pilot cavern for underground cryogenic LNG (Liquefied Natural Gas) storage. The monitoring was mainly focused on the operation of a drainage and recharge system. After the operation of the drainage system commenced, the drainage rate decreased rapidly in the initial stages and then decreased gradually. Hydrogeological monitoring revealed that the rock drainage system operated effectively. During drainage, the water table was maintained below the cavern roof. The recharge for ice-ring formation was performed in two phases. The first phase involved the cessation of pumping in downward-drainage holes and the second involved the closure of upward boreholes. Since the water table was maintained below the cavern roof, artificial recharge was planned at first. However, it was not implemented due to heavy rainfall in the recharge stage. On the basis of hydrogeological monitoring and hydraulic tests, it was found that the fractures above the roof and on the right wall of the pilot cavern mainly affected seepage into the cavern and thermal variation due to the storage of liquid nitrogen. Thermal variation was examined by the thermometers installed around the pilot cavern. The cooling and thawing processes reveal the characteristics of thermal distribution in the rock and the 0 °C isotherm. The cooling phase lasted for six months, and the 0 °C isotherm progressed in time after the injection of liquid nitrogen into the cavern. The isotherm propagated up to about 4 m from the floor and the sidewall of the cavern and about 3 m from the cavern roof. The cooling rate of the rock mass above the cavern roof was lower than that of the other cavern sides due to the gaseous space in the upper part of the containment. The fractures were analyzed and considered for thermal modeling. A two-dimensional finite element analysis was performed to compare the field monitoring at the pilot cavern. The numerical modeling shows the distance between the ice ring and heat transfer pattern of the fractures around the pilot cavern. The propagation of the measured and calculated 0 °C isotherm reveals that the water-conveying joint on the right wall might affect thermal propagation through a thermal pipe. 相似文献
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规范、完善的土地交易市场,不仅是地方经济社会发展与成熟的重要标志,也是保证土地资源参与宏观调控的有利手段。近年来,淄博市国土资源局淄川区分局为进一步加强土地管理,积极发挥有形土地市场的作用,满足地方经济发展用地需求,逐步探索出了土地交易市场建设“一二三四五”的工作思路,不仅扭转了土地需求决定土地供给的局面,而且创造了良好的用地环境,为淄川区的经济发展注入了强大活力。 相似文献
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通过T639模式预报产品在内蒙古地区降水量、2 m温度、相对湿度和10 m风向、风速及降水过程预报效果的适用性研究,得出以下结论,温度和相对湿度预报的准确率较风向、风速明显偏高,温度和相对湿度预报的误差系统偏小,风速预报误差偏大的概率较大;降水量的预报准确率随降水等级增加而递减,对小雨而言,模式漏报率小于空报率,多报降水的偏差和少报降水的偏差相近。在预报要素空间分布上,风向预报的偏差顺时针偏转,其夹角小于45°,温度预报偏差总体偏小,相对湿度预报偏差由西向东表现为“+、-、+、-”的分布特征;小雨和中雨落区预报偏大,暴雨落区预报偏小;贝加尔湖冷涡强度的预报偏强,西太平洋副热带高压的强度预报偏弱,影响范围偏西偏北。 相似文献