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陈国强  陈鹏 《海洋学报》2004,26(4):89-95
以厦门马銮湾为研究区域,在分析景观异质性的基础上,采用地质统计学的理论和方法并结合GIS强大的空间分析和显示功能,通过一定的数学模型和生态效应分布图的表示方法,对快速城市化过程中区域景观异质性变化和由此导致的景观生态效应程度进行了定性和定量相结合的综合评估,结果表明,城市景观的同化过程是区域景观结构和景观异质性变化的主要表现,景观生态效应空间分布图也表明城市化对应的生态学过程的规模效应在整个规划区内有扩大的趋势。  相似文献
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江苏条子泥岸滩剖面形态的时空异质性   总被引:2,自引:2,他引:0       下载免费PDF全文
在江苏条子泥岸滩选择3个典型剖面,对其进行了3a定期的观测,将所得剖面数据绘制成剖面形态曲线。通过对岸滩剖面形态的分析,发现3a来岸滩冲淤变化明显,岸滩剖面形态内部及其相互间都有变化,呈现不同的类型。探讨了其变化的机制,包括自然因素和人为因素。主要的研究结果将丰富人们对江苏条子泥近期岸滩及辐射沙洲演变的认识,为条子泥促淤并陆和海岸防护等工程提供科学依据。  相似文献
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在水文状况、水质状况、生态类型均显著不同的三个太湖典型湖区, 利用^210Pb定年测定了近百年来沉积物及磷的沉积通量.结果发现, 三个湖区磷的沉积通量及其变化规律相差很大.发生蓝藻水华暴发的梅梁湾近百年来沉积物和磷的沉积通量都比较小, 只是在近十几年来才有明显增加的趋势; 太湖上游的夹浦沉积物沉积速率近百年来持续增加, 只有表层有所下降, 但表层12cm沉积物中磷的沉积通量却显著下降; 处于太湖下游草型化的胥口湾湖区, 在20世纪60年代以前沉积物沉积通量呈增加趋势, 之后呈下降趋势, 磷的沉积通量则呈振荡下降趋势.研究表明, 太湖沉积物中磷的累积通量具有明显的空间异质性.  相似文献
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Seasonal variations in zooplankton abundance,biomass,species diversity and community structure were investigated in the Sanmen Bay,China.Samples were collected from 15 stations,on the seasonal basis,in April(spring),July(summer) and October 2005(autumn) and January 2006(winter),respectively.The results show that zooplankton species number,abundance and biomass varied widely and had distinct spatial heterogeneity in the Sanmen Bay.A total of 72 species of zooplankton belonging to 56 genera and 17 groups of pelagic larvae were identified.The zooplankton species richness was strongly related to salinity.Based on hierarchical cluster analysis,zooplankton in this study area were classified into three groups:coastal,neritic and pelagic groups,which corresponded to the upper,middle and lower portion of the Sanmen Bay,respectively.The coastal low-saline species were dominant in the study area.The zooplankton abundance and biomass reached a peak in summer,moderate in spring and autumn,and the lowest in winter.Zooplankton abundance decreased from the upper to lower portion of the bay in April,when the highest biomass occurred in the middle portion of the bay.There were the same spatial distribution patterns for the biomass and abundance in July,with the maximum in the middle of the bay.However,zooplankton abundance was the highest in the middle of the bay in October,when maximum biomass occurred near the lower of the bay.Zooplankton abundance and biomass were evenly distributed in the Sanmen Bay in January.Spatial and temporal variations in zooplankton and their relationship with environmental factors were also analyzed.The BIOENV results indicate that the combination of chlorophyll a(Chl-a),salinity,dissolved inorganic nitrogen(DIN),dissolved oxygen(DO) and silicate(SiO3) was responsible for the variations in zooplankton community structure in the Sanmen Bay.The environmental changes played an important role in changes in the zooplankton community structure in the Sanmen Bay.  相似文献
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文章基于青岛市321个海洋渔户样本的调查数据,运用Logistic模型对异质性渔户海洋渔业技术需求的影响因素进行分析。研究表明,全体渔户的家庭年均收入、家庭成员从事技术推广工作情况和生产方式3个因素具有显著正向影响,学历和享有补贴情况2个因素具有显著负向影响;捕捞渔户的生产方式因素具有显著正向影响,享有补贴情况因素具有显著负向影响;养殖渔户的家庭年均收入和生产方式具有显著正向影响,从事渔业生产的时间具有显著负向影响。基于研究结论提出对策建议,即加强对渔户的文化教育,提升渔户整体素质;加强海洋渔业技术推广体系建设,满足异质性渔户海洋渔业技术需求;建立捕捞渔户渔业生产补贴的监管机制;结合养殖渔户海洋渔业技术需求开展普及性和针对性培训。  相似文献
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