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通过对水库中12个围隔两次取样的叶绿素a浓度(单位:μg/L)、化学耗氧量(单位:mg·O_2/L)和塞克透明度(单位:m)的实验数据分析,求得如下回归方程: (1)[Chla]=17.60·[SD]~(-1·86) r=-0.87 (2)[Chla]=-28.85+7.32·[COD] r=0.89 (3)[COD]=6.88·[SD]~(-0·68) r=0.91本文还对这些结果进行了讨论。 相似文献
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Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these studies have been barely carried in the Bohai Sea. The sea-ice microwave scattering mechanism was first developed for the thin sea ice with slight roughness in the Bohai Sea in the winter of 2012, and included the backscattering coefficients which were measured on the different conditions of three bands(L, C and X), two polarizations(HH and VV), and incident angles of 20° to 60°, using a ground-based scatterometer and the synchronous physical parameters of the sea-ice temperature, density, thickness, salinity, and so on. The theoretical model of the sea-ice electromagnetic scattering is obtained based on these physical parameters. The research regarding the sea-ice microwave scattering mechanism is carried out through two means, which includes the comparison between the field microwave scattering data and the simulation results of the theoretical model, as well as the feature analysis of the four components of the sea-ice electromagnetic scattering. It is revealed that the sea-ice microwave scattering data and the theoretical simulation results vary in the same trend with the incident angles. Also, there is a visible variant in the sensitivity of every component to the different bands.For example, the C and X bands are sensitive to the top surface, the X band is sensitive to the scatterers, and the L and C bands are sensitive to the bottom surface, and so on. It is suggested that the features of the sea-ice surfaces and scatterers can be retrieved by the further research in the future. This experiment can provide an experimental and theoretical foundation for research regarding the sea-ice microwave scattering characteristics in the Bohai Sea. 相似文献
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踩踏对砂质滩小型底栖动物的影响——现场扰动实验初步结果 总被引:1,自引:0,他引:1
在青岛太平湾砂质滩进行人为踩踏扰动现场实验,初步了解踩踏对砂质滩小型底栖动物的影响。现场扰动实验结果显示,受踩踏影响小型底栖动物垂直分布在12 h内发生了显著的变化。小型底栖动物对人为踩踏扰动的响应模式为向深处迁移致使丰度降低,并非平行向周围迁移。同时,本研究比较分析了旅游旺季(7月)和淡季(10月)小型底栖动物的丰度和分布,结果显示,旅游旺季小型底栖动物丰度及其优势类群海洋线虫丰度明显低于淡季,并在中潮带表现突出。季节影响之外,旅游活动,包括沙滩上的散步、奔跑、嬉戏及浅海区的游泳活动引起的沉积物改变可能是导致小型底栖动物的丰度、组成及分布变化的重要原因之一。有关小型底栖动物群落对旅游扰动的响应机理还需要在更广的范围开展更深入的研究。 相似文献
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《测绘科学技术学报》2013,(4)
结合传统的实验思想与方法以及最新的虚拟地理技术,阐述并发展"虚拟地理实验"思想、概念、特征与方法。从虚拟地理环境、三条黄河、仿真虚拟科学等阐述了虚拟地理实验思想的最初形成与发展;从实践哲学角度,探讨了虚拟实践的特征、以及与现实实践的相互关系,并认为复杂性地理科学的研究需要集成现场实验、实验室实验以及计算虚拟实验等的多样化实践形式。探讨虚拟地理实验的特征、类型,尝试建立虚拟地理实验核心理论的虚实相似原理和虚实协同原理;最后,以洪水动力过程与人群活动过程为例,开展了虚拟自然地理实验与虚拟人文地理实验的初步应用原型试验。 相似文献