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21.
南海北部海区水团的判别分析 总被引:1,自引:0,他引:1
将判别分析应用于南海北部海区的水团分析。划分为八个水团:沿岸冲淡水团(F),近岸混合水团(M),暖表层水团(WS),表层水团(S),表—次层混合水团(SU),次层水团(U),次—中层混合水团(UI)和中层水团(I)。给出了各水团在四季代表月的Bayes多组判别的系数和参数。用资料检验判别的成效.冬季和春季可达95.90%以上,夏季为94.80%,秋季是全年最低值,为92.72%。讨论了造成错判的原因,并与Fisher判别作了比较。当测值维数较低时,建议选用Bayes判别。对八个水团以及各水团两两之间差异的显著性进行了检验,证实在每个季节中各水团之间的差异,都在高度置信水平(α=0.01)上具有显著性。因而,划分为八个水团是有实际意义的,其判别式的系数和参数,可用于实际的判别和预报。 相似文献
22.
粘质沙雷氏菌(Serratia marcescens)发酵培养基优化的研究 总被引:6,自引:0,他引:6
采用单因素试验和正交试验,对从山东东营海岸湿地盐碱滩地土壤中筛选出的一株海洋菌种———粘质沙雷氏菌(Serratia marcescens)的发酵培养基进行优化,并进行100 L发酵罐中试放大试验的研究。确定粘质沙雷氏菌的最佳培养基配方为葡萄糖10 g/L,硫酸铵5 g/L,麸皮50 g/L,柠檬酸三钠1.0 g/L,K2HPO4.3H2O 0.3 g/L,FeSO4.7H2O 0.05 g/L,MgSO4.7H2O 0.5 g/L,pH 7.2~7.7。发酵最适温度为30℃。通过测定粘质沙雷氏菌在发酵罐中培养的生长曲线,确定发酵时间以28~30 h为宜,发酵结束后发酵液中的活菌数约为50×108个/mL。将所筛选到的粘质沙雷氏菌应用于农作物的病害防治,效果非常显著,表明是一株高活性的生物防治拮抗菌。此研究结果为高效率、低成本和工业化生产具有生物防治作用的海洋菌种制剂提供了科学依据,也为海岸湿地盐碱土的可持续开发利用提供了技术支撑。 相似文献
23.
东北三省城市扩展及植被覆盖状况 总被引:1,自引:0,他引:1
基于三期遥感影像数据( MSS、ETM、CBERS) 对城市建成区的面积进行了调查,研究30 多年来东北三省城市的扩展情况,并且结合NDVI 数据,对研究区范围内的植被覆盖情况进行了研究。结果表明: 1976-2000 年、2000-2007 年两个阶段,城市建成区的面积持续增加,年均扩展率由 5. 10%增加至6. 32%,扩展强度比较显著的区域主要分布在哈大交通经济带上; 研究区范围内东部的植被覆盖情况明显好于西部,NDVI 均值随与城市距离的增加而提高。 相似文献
24.
基于2006~2007年福建沿岸海域4个航次的底拖网调查,分析了福建沿岸海域石首鱼科鱼类的资源现状.结果表明:4个航次共捕获石首鱼类16种,其中春季捕获石首鱼类10种,夏季和冬季均捕获14种,秋季捕获12种.不同航次捕获的石首鱼类占所有鱼类总渔获量的比例为10.43%~23.23%,平均15.71%.平均资源密度和平均个体密度分别为81.49 kg/km2和3 663.06 ind./km2.平均资源密度和平均个体密度均以秋季最高,分别为130.02 kg/km2和5 702.64 ind./km2.闽东沿岸海域、闽江口及其附近海域、闽中沿岸海域和厦门沿岸海域石首鱼类的全年平均资源密度分别为70.75、96.23、22.54和84.57 kg/km2.在各种石首鱼类中,叫姑鱼(Johnius belengerii)的资源密度和个体密度最大,其次是丁氏(Wak tingi).叫姑鱼的相对重要性指数最高,为871.01,仅叫姑鱼为优势种.与近20 a前的调查资料相比较,石首鱼类的渔获量占鱼类总渔获量的比例升高,但资源密度显著下降,必须采取措施,避免开发强度的继续增加,以利于其资源的可持续利用. 相似文献
25.
Coastline configuration and geomorphologic development mode of arc-shaped coast in South China 总被引:1,自引:0,他引:1
1IntroductionArc-shaped bays are quite common on exposed sediment coast in South China, where the crenulate-bay beaches occur with the presence of two consecutive headlands and a predominant wave approach oblique to the alignment of the upcoast and downcoast headlands (Yasso, 1965). Oblique persistent swell striking a shoreline transports sediment alongshore and sculptures a coast into arc-shaped beaches. The shoreline of beach appearance mainly consists of straight segment and shadow segment… 相似文献
26.
东海东北部春季若干重要水文结构的分析 总被引:7,自引:2,他引:7
本文主要基于韩国海洋研究所在东海沿岸海洋过程试验中收集的CTD资料,分析了1995年春季出现在东海东北部的一些重要水文结构。结果表明,一种锋涡状结构出现在黑潮向东转折点附近。它不仅使邻近海域的水文结构变得更复杂,而且诱发黑潮水与陆架水间活跃的交换。在陆架坡折处观测到若干孤立的陆架水块,可能是锋涡的卷挟作用所致;该海域存在4个水团,即黑潮水、对马暖流水、陆架水和混合水。对马暖流水分为上下两层:上层水为变性黑潮水,盐度比黑潮水约低0.1,底层对马暖流水仅位于冲绳海槽区,并有着与黑潮中层水相同的温、盐特性;一种双锋结构出现在邻近黑潮的陆架边缘附近。在内陆架形成的陆架锋,由北向南伸展时,愈来愈偏向陆架边缘。而黑潮锋沿九州以西深槽的陆架边缘向北伸展。在黑潮转折点附近,两锋几乎合并为一条锋。狭窄的锋带由黑潮水及其变性水和陆架水的混合水所占据。 相似文献
27.
Jian Chen Guijian Liu Mengmeng JiangChen-Lin Chou Hui LiBin Wu Liugen ZhengDongdong Jiang 《International Journal of Coal Geology》2011,88(1):41-54
To study the geochemical characteristics of 11 environmentally sensitive trace elements in the coals of the Permian Period from the Huainan coalfield, Anhui province, China, borehole samples of 336 coals, two partings, and four roof and floor mudstones were collected from mineable coal seams. Major elements and selected trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and hydride generation atomic absorption spectrometry (HAAS). The depositional environment, abundances, distribution, and modes of occurrence of trace elements were investigated. Results show that clay and carbonate minerals are the principal inorganic constituents in the coals. A lower deltaic plain, where fluvial channel systems developed successively, was the likely depositional environment of the Permian coals in the Huainan coalfield. All major elements have wider variation ranges than those of Chinese coals except for Mg and Fe. The contents of Cr, Co, Ni, and Se are higher than their averages for Chinese coals and world coals. Vertical variations of trace elements in different formations are not significant except for B and Ba. Certain roof and partings are distinctly higher in trace elements than underlying coal bench samples. The modes of occurrence of trace elements vary in different coal seams as a result of different coal-forming environments. Vanadium, Cr, and Th are associated with aluminosilicate minerals, Ba with carbonate minerals, and Cu, Zn, As, Se, and Pb mainly with sulfide minerals. 相似文献
28.
Quantitative assessment of vulnerability is a core aspect of wetland vulnerability research. Taking Baiyangdian (BYD) wetlands in the North China Plain as a study area and using the ‘cause-result’ model, 23 representative indicators from natural, social, sci-tech and economic elements were selected to construct an indicator system. A weight matrix was obtained by using the entropy weight method to calculate the weight value for each indicator. Based on the membership function in the fuzzy evaluation model, the membership degrees were determined to form a fuzzy relation matrix. Finally, the ecological vulnerability was quantitatively assessed based on the comprehensive evaluation index calculated by using a composite operator to combine the entropy weight matrix with the fuzzy relation matrix. The results showed that the ecological vulnerability levels of the BYD wetlands were comprehensively evaluated as Grade II, Grade Ⅲ, Grade IV, and Grade Ⅲ in 2010, 2011-2013, 2014, and 2015-2017, respectively. The ecological vulnerability of the BYD wetlands increased from low fragility in 2010 to general fragility in 2011-2013, and to high fragility in 2014, reflecting the fact that the wetland ecological condition was degenerating from 2010 to 2014. The ecological vulnerability status then turned back into general fragility during 2015-2017, indicating that the ecological situation of the BYD wetlands was starting to improve. However, the ecological status of the BYD wetlands on the whole is relatively less optimistic. The major factors affecting the ecological vulnerability of the BYD wetlands were found to be industrial smoke and dust emission, wetland water area, ammonia nitrogen, total phosphorus, rate of industrial solid wastes disposed, GDP per capita, etc. This illustrates that it is a systematic project to regulate wetland vulnerability and to protect regional ecological security, which may offer researchers and policy-makers specific clues for concrete interventions. 相似文献
29.
南海西部表层沉积物钙质浮游生物分布与碳酸盐溶解 总被引:1,自引:0,他引:1
对南海西部300多个表层沉积样品中的浮游有孔虫和钙质超微化石定量分析表明,几乎所有样品均含浮游有孔虫、钙质超微化石,但丰度相差十分悬殊,浮游有孔虫丰度介于0.5~36673个/g之间,钙质超微化石丰度为0~1725个/10个视域,两者的分布规律相似。在陆坡区钙质浮游生物最富集,尤其在西沙群岛西南、南沙西部礁滩附近海区丰度最高;向深海盆区和陆架浅水区,钙质浮游生物丰度均下降。但从两者的丰度分布来看,其溶解程度不同,浮游有孔虫更容易溶解,在200~2000m水深区,丰度最高,2000m以下丰度锐减;而钙质超微化石的最富集区在500~3000m,且3000m以下仍较丰富。从碳酸盐的分布来看,本区碳酸盐的临界补偿深度(CCrD)为3500m,而CCD大于4300m,碳酸盐的溶解主要由有孔虫和钙质超微化石构成。 相似文献
30.
Chinese overseas industrial parks in Southeast Asia: An examination of policy mobility from the perspective of embeddedness 总被引:2,自引:2,他引:2
The development of overseas industrial parks is a key component of the Belt and Road Initiative and an expected experimental way of promoting inclusive globalization by inventing new forms of cooperation between China and local host countries. Policy mobility, a classic theory within international political geography addressing the connection between local and global policies, has implications for overseas industrial parks development. In this paper, we argue that policies are not easily moved directly from one place to another; instead, policies are embedded due to the role of local actors in policy mobility. This article first provides an overview of seven China-Southeast Asia economic and trade cooperation zones identified by the Ministry of Commerce, and analyzes their key participants. It then discusses policy mobility by looking into the roles of revenue, land, and talent in developing these industrial parks. The paper finds that these parks face challenges, such as the complicated geographical environments of host countries, huge pressure from enterprise investment capital, the lack of overseas service platforms, and underdeveloped agglomeration economies. In the light of the current situation, policy suggestions for the future sustainable development of overseas industrial parks are put forward. 相似文献