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41.
This study showed how the daytime length in Jiaozhou Bay affected the water temperature, which in turn affected the phytoplankton growth when solar radiation was sufficient for phytoplankton photosynthesis. Jiaozhou Bay observation data collected from May 1991 to February 1994 were used to analyze the daytime length vs water temperature relationship. Our study showed that daytime length and the variation controlled the cycle of water temperature flunctuation. Should the cyclic variation curve of the daytime length be moved back for two months it would be superimposed with temperature change. The values of daytime length and temperature that calculated in the dynamical model of daytime length lag vs water temperature were consistent with observed values. The light radiation and daytime length in this model determined the photochemistry process and the enzymic catalysis process of phytoplankton photosynthesis. In addition, by considering the effect of the daytime length on water temperature and photosynthesis, we could comprehend the joint effect of daytime length, water temperature, and nutrients, on the spatiotemperal variation of primary production in Jiaozhou Bay.  相似文献   
42.
Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheric carbon in the Northern Pacific Ocean (NPO), as well as the variation in space-time distribution of phytoplankton primary production and atmospheric carbon in the study regions. The study indicates that the human beings have imposed an important impact on the changing trends of the atmospheric carbon. Primary production in the Jiaozhou Bay presents a good example in this regard. In this paper, dynamic models of the atmospheric carbon in the NPO, the cyclic variations in the atmospheric carbon, and primary production in the Jiaozhou Bay are studied with simulation curves presented. A set of equations were established that able to calculate the rate and acceleration of increasing carbon discharged anthropologically into the atmosphere and the conversion rate of phytoplankton to atmospheric carbon. Our calculation shows that the amount of atmospheric carbon absorbed by one unit of primary production in the Jiaozhou Bay is (3.21−9.74)×10−9/(mgC·m−2d−1), and the amount of primary production consumed by a unit of atmospheric carbon is 102.66–311.52 (mgC·m−2d−1/10−6). Therefore, we consider that the variation of atmospheric carbon is a dynamic process controlled by the increase of carbon compound and its cyclic variation, and those from anthropologic discharge, and phytoplankton growth.  相似文献   
43.
GIS支持下人类活动对地下水动态影响的定量分析   总被引:2,自引:0,他引:2       下载免费PDF全文
应用地球动力学原理分析和研究了人类活动对水资源变化的影响,提出可将人为作用影响作为一个综合性的抽象指数,通过求取其它因素的变化利用余差法反求得到的计算思路.借助于GIS技术,建立了度量人为作用对地下水动态影响的通用数学模型,并用实例进行了验证,计算结果与实际情况相符,表明所提的方法是可行的.  相似文献   
44.
贵州晴隆大厂锑矿床成因探讨   总被引:19,自引:0,他引:19  
晴隆大厂锑矿田是我国锑矿重要产地之一。我们在长期野外地质工作的基础上,结合近年来系统采集的岩矿、光谱、化学、包体、硫同位素及氢同位素等测试资料的综合研究,对大厂锑矿床的成因有一个初步认识,现撰写成此文。限于作者水平有限,谬误之处难免,敬请批评指正。本文所用的测试资料,承蒙中国科学院地球化学研究所、贵州省地质局实验室、冶金工业部地质研究所协助分析,此外还引用了中国科学院地球化学研究所、贵州省地质局原112地质队有关本区的硫同位素测试资料,在此一并致谢。  相似文献   
45.
胶州湾水温和营养盐硅限制初级生产力的时空变化   总被引:8,自引:2,他引:6  
根据作者近年来对胶州湾水域的主要研究结果,分析和探讨了营养盐硅和水温对浮游植物生长的变化和其集群结构的改变影响,研究了胶州湾初级生产力的年变化过程是如何受到营养盐硅和水温的限制和提高,其时间阶段和空间区域又如何划分,营养盐硅和水温如何控制不同阶段和不同区域的初级生产力。同时,揭示了营养盐硅或水温在时间和空间的尺度上如何控制浮游植物生长的变化过程,而且在时空的变化中,2种因子营养盐硅和水温在时间和空间的尺度上又如何有顺序的控制,产生出各种类型的生产力。研究结果展示了在初级生产力的时间和空间的变化过程中,营养盐硅和水温控制初级生产力的不同时间阶段,尤其用增殖能力展示了水温对浮游植物生长的控制时间阶段;营养盐硅控制初级生产力的不同空间区域。从而阐明了营养盐硅和水温控制初级生产力的变化过程。从陆地到海洋界面的硅输送量决定了初级生产力的时间变化过程;硅的生物地球化学过程决定了初级生产力的空间变化过程。因而,营养盐硅和水温是浮游植物生长的“发动机”,营养盐硅是主要的,而水温是次要的。  相似文献   
46.
1985年8月至1986年8月在长江口及其附近海域的50个大面观测站进行了磷酸盐和初级生产力逐月调查。通过分析磷酸盐的水平分布特征,发现长江口海域的磷酸盐浓度没有明显的季节变化,几乎不受长江流量变化的影响,因此认为,长江输送磷酸盐浓度不能由丰水期与枯水期决定;磷酸盐浓度与初级生产力的断面分布和时间变化的分析表明,磷酸盐浓度并不一定离岸越远越低,也没有周期性的季节变化;初级生产力的值几乎不受磷酸盐浓度变化的影响。根据营养盐限制的判断方法和法则,在长江口及其附近海域,磷并不是浮游植物生长的限制因子,仅靠氮磷比值来得到磷限制或氮限制的结论是不完善的。  相似文献   
47.
地球生态系统的营养盐硅补充机制   总被引:7,自引:0,他引:7  
通过海洋生态系统的结构和功能以及海洋生态系统对大气生态系统和陆地生态系统的影响,根据营养盐硅对浮游植物生长的影响过程和浮游植物的生理特征以及其集群结构的改变特点的研究结果,综合分析了硅的生物地球化学过程,探讨了人类对生态环境的影响和生态环境变化对地球生态系统的影响。提出了地球生态系统的营养盐硅的补充机制:近岸的洪水、大气的沙尘暴和海底的沉积物向缺硅的水体输入大量的硅,即由陆地、大气、海底3种途径将硅输入海水水体中,满足浮游植物的生长的需要,保持海洋中浮游植物生长的动态平衡,促进海洋生态系统的可持续发展。  相似文献   
48.
文章在分析国际深海资源发展趋势的基础上,综述了近年来国内外在深海技术方面的研究发展现状;进一步阐述了发展深海技术、开发深海资源对于可持续发展战略的重要意义;最后对我国深海技术的发展提出了几点建议。  相似文献   
49.
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO3^--N, NO2^--N, NH4^ -N, SIO3^2--Si, PO4^3--P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq. ( 1 ) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature‘s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant-nutrient concentTations but low phytoplankton biomass in some waters is reasonably explained in this paper.  相似文献   
50.
根据1979年的胶州湾水域调查资料,分析了重金属铬在胶州湾水域的分布、迁移和季节变化。研究结果表明;春季,胶州湾水城铬污染较轻,大部分海域水质状况较好,而到夏季没有受到污染。在时空分布上,春季,铬污染形成了明显的梯度,由东北向西南方向递减,从112.3μg/L降低到0.2μg/L。夏季,铬的水平分布比较均匀,表层水体铬的含量较低,范围在0.10~1.40μg/L之间波动。因此认为,1979年整个胶州湾水域的重金属铬属于面污染源。而且,当铬进入胶州湾海域后,很快吸附在水体中的悬浮颗粒上,并被水流较快地带离胶州湾水城,几乎没有在胶州湾水域表、底层留下污染痕迹。  相似文献   
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