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通过公开选拔,4月13日,黑龙江省委常委会议决定,原大兴安岭地区行署国土资源局局长阎镇海任省有色金属地质勘查局副局长、党组成员。 相似文献
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基于多源遥感的广东镇海湾红树林演变分析 总被引:1,自引:0,他引:1
利用4 期多源遥感数据(包括1970 年的美国间谍卫星DISP KH-9 数据、1999 年的SPOT-2 全色数据、2007 年的ALOS 多光谱数据和2015 年国产的资源三号数据),结合红树林湿地资源的空间分布特征及先验知识,基于面向对象的多尺度分割提取红树林植被斑块,采用目视解译获取多时相红树林空间分布精确信息。结果表明:1970、1999、2007 和2015 年镇海湾红树林有林地面积分别为931.4、615.3、678.5 和783.7 hm2,红树林面积呈现出先减少后增加的趋势。1970―1999 年,该区域以原生红树林被破坏为主,仅有5.7%的原生林被保存下来。1999―2015 年,红树林的人为破坏与人工修复现象并存,但总体上破坏程度有所降低;其中1999―2007、2007―2015年间红树林面积分别增加了63.2 和105.2 hm2。养殖塘侵占和人工恢复种植的综合影响,以及海岸线周边人为活动变化是驱动红树林有林地时空变化的主要因子。最后,提出了一系列有针对性的红树林保护与发展的措施,为合理地开发和更好地保护红树林资源提供决策支持。 相似文献
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In order to better understand the general tidal features in the venturi-shaped area between Zhenhai and Shenjiamen in the northern coastal region of Zhejiang Province in the East China Sea, the tidal data were obtained from both the three permanent tide stations of Zhenhai, Dinghai and Shenjiamen, and four temporary tide stations of Mamu, Chuanshan, Guoju and Liuheng, along with the current speed being observed at Luotou Waterway. Results from harmonic analysis show that: (1) The area was dominated by shallow water tides with irregular semi-diurnal features, and the smallest tidal range occurred in the area near a crossing line between Zhenhai and Dinghai stations, indicating that a tidal node existed in the southern Hangzhou Bay; (2) Formulae, HS2/HM2 >0.4 and gM2-(gK1+gO1)=270° (where H and g are harmonic constants), could be used as judging criteria for high and low tidal level diurnal inequalities; (3) The duration difference between ebb and flood tides could be roughly assessed by the ratio of HM4 vs. HM2; and the larger the ratio is, the bigger the duration difference is. At the same time, the duration period could be assessed by 2gM2-gM4, the epoch difference between M2 and M4 tidal constituents. If 2gM2-gM4 <180°, then the ebb duration is longer than the flood duration; if 180°< 2gM2-gM4 <360°, the result is reversed; (4) Taking Dinghai station as a center point, the highest tidal levels and the average high tidal levels, as well as the average tidal ranges at all stations became higher and larger both southeastwards and northwestwards, while the lowest tidal levels and the average low tidal levels appeared to be lower both southeastwards and northwestwards; and (5) The tidal patterns were not all in line with the tidal current patterns. As a conclusion, the smallest tidal range occurred in the narrow part of the venturi-shaped area. Along the both sides of the area, the highest tidal level and tidal range became higher and larger, while the lowest tidal level became lower with the increase of the distance from the narrow throat area. This is somehow different from the theory that the tidal level increases gradually when it moves towards the top narrow area of a V-shaped bay or estuary. 相似文献
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针对浙江镇海潮间带沉积物样 品,采用纯培养法分离培养海洋微生物,并基于16S rRNA基因序列,开展系统发育学研究,分析沉积物细菌群落结构及多样性。分离获得细菌39株,16S rRNA基因序列分析表明,这些菌株分别属于厚壁菌门Firmicutes(51. 3%)、变形杆菌门Proteobacteria(30.8%)、拟杆菌门Bacteroidetes(15. 4%)和放线菌门Actinobacteria(2. 6%)4个类群。厚壁菌门和变形杆菌门的菌株主要归属于芽孢杆菌纲Bacilli和a-变形杆菌纲Alphaproteobacteria,它们可能在近海海洋生态系统的元素地球化学循环中发挥了重要作用。此外,部分菌株16S rRNA基因序列与已报道物种的相似性较低,可能代表了新的分类单元。研究丰富了浙江近海微生物种质资源,并拓展了对浙江近海可培养细菌多样性的认识,为今后开发利用海洋微生物资源积累了资料。 相似文献