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881.
Relationship between economic growth and water environmental quality of Anshan city in Northeast China 总被引:1,自引:0,他引:1
Based on the decomposition model of environmental quality and univariate regression model, the relationships of industrial wastewater drainage with economic scale, economic structure, and technological level in Anshan, a mining city in Northeast China, were studied. The results showed that, due to scale effect, the drainage of three important industrial wastewater pollutants (COD, NH3-N and petroleum) increased 8505t, 671t and 384t, respectively, and due to structure effect, those pollutants drainage increased 3996t, 174t and 120t from 2001 to 2006. While due to technological effect, the drainage of COD, NH3-N and petroleum reduced 4452t, 458t and 331t, and due to cross effect, those pollutants drainage reduced 7270t, 575t and 476t simultaneously. Meantime, the relationships between household consumption structure and domestic sewage discharge were analyzed, and domestic sewage discharges in different income levels were also compared. The results showed that, the domestic sewage discharges would increase 376t with 1000 yuan (RMB) increased in the traffic and communication consumption, and they would be 344t, 219t, 428t, 1873t, respectively, in housing consumption, food consumption, medical consumption, miscellaneous commodity consumption. The proportion of domestic sewage discharge increased for high income residents significantly, but reduced for lower income residents. The industrial wastewater pollutants drainage tends to be reduced by technical progress, while domestic sewage discharge will be a more important factor for urban water environment quality. 相似文献
882.
A one-year field study was conducted to determine the conversion ratio of phytoplankton biomass carbon (Phyto-C) to chlorophyll-a (Chl-a) in Jiaozhou Bay, China. We measured suspended particulate organic carbon (POC) and phytoplankton Chl-a samples collected in surface water monthly from March 2005 to February 2006. The temporal and spatial variations of Chl-a and POC concentrations were observed in the bay. Based on the field measurements, a linear regression model II was used to
generate the conversion ratio of Phyto-C to Chl-a. In most cases, a good linear correlation was found between the observed POC and Chl-a concentrations, and the calculated conversion ratios ranged from 26 to 250 with a mean value of 56 μg μg−1. The conversion ratio in the fall was higher than that in the winter and spring months, and had the lowest values in the
summer. The ratios also exhibited spatial variations, generally with low values in the near shore regions and relatively high
values in offshore waters. Our study suggests that temperature was likely to be the main factor influencing the observed seasonal
variations of conversion ratios while nutrient supply and light penetration played important roles in controlling the spatial
variations. 相似文献
883.
884.
885.
GPS网中已知点间兼容性检验的探讨 总被引:1,自引:0,他引:1
为各项测绘工程建立的GPS控制网都应以一定的已知点作为约束数据进行约束平差,求得网中各点在国家坐标系统或地方独立坐标系统中的坐标成果并得以应用,所以已知点间的兼容性对于保证GPS控制网的整体精度和点位坐标值的正确性非常重要。本文就相关规范的规定提出坐标及边长回归分析法进行已知点间兼容性检验,并使用几种常用的GPS平差软件结合实例进行计算和分析,成功地选定相兼容的已知点;并就实际生产中对已知点的联测和使用提出了建议。 相似文献
886.
土壤有机质光谱特征研究(英文) 总被引:1,自引:0,他引:1
The study on soil spectral reflectance features is the physical basis for soil remote sensing. Soil organic matter content
influences the soil spectral reflectance dramatically. This paper studied the spectral curves between 400 nm∼2500 nm of 174
soil samples which were collected in Hengshan county and Yixing county. Fourteen types of transformations were applied to
the soil reflectance R to remove the noise and to linearize the correlation between reflectance (independent variable) and soil organic matter (SOM)
content (dependent variable). Then, the methods such as derivative spectrum technology and stepwise regression analysis, were
applied to study the relationship between these soil spectral features and soil organic matter content. It shows that order
1 derivative of the logarithm of reflectance (O1DLA) is the most sensitive to SOM among the various transform types of reflectance
in consideration. The regression model whose coefficient of determination reaches 0.885 is built. It predicted the soil organic
matter content with higher effect.
Supported by the National Natural Science Foundation of China (No. 40271007). 相似文献
887.
分析了近10年来随着旅游经济的增长各类土地利用类型的变化情况,探索在当前经济发展形势下,各类用地类型的变化与旅游经济增长之间的内在联系.在得出的数学模型基础上,预测部分地类用地的数量及旅游经济的发展规模,为土地利用规划和旅游规划提供帮助. 相似文献
888.
M.A.K. El-ghali S. Morad H. Mansurbeg Miguel A. Caja M. Sirat N. Ogle 《Marine and Petroleum Geology》2009
The distribution of diagenetic alterations in Triassic fluvio-deltaic, quartzarenitic to sublitharenitic, lowstand systems tract (LST) sandstones of the Grès á Voltzia Formation, anastomosing fluvial, quartzarenitic transgressive systems tract (TST) sandstones of the Grès á Roseaux Formation, and shallow marine, quartzarenitic to sublitharenitic, TST sandstones of the Grès Coquiller Formation, the Paris Basin (France), can be linked to transgression and regression events, and thus to the sequence stratigraphic context. Near-surface eogenetic alterations, which display a fairly systematic link to the depositional facies and sequence stratigraphic framework, include: (i) cementation by meteoric water calcite (δ18O=−8.9‰ and δ13C=−9.1‰) in the fluvio-deltaic, LST sandstones, (ii) cementation by mixed marine–meteoric calcite (δ18O=−5.3‰ to −2.6‰ and δ13C=−3.9‰ to −1.3‰) and dolomite (δ18O=−4.6‰ to −2.6‰ and δ13C=−2.9‰ to −2.3‰) in the foreshore, TST sandstones and below parasequence boundaries (PB), and transgressive surface (TS), and in the shoreface, TST sandstones below maximum flooding surfaces (MFS), being facilitated by the presence of carbonate bioclasts, (iii) dissolution of detrital silicates and precipitation of K-feldspar overgrowths and kaolinite, particularly in the fluvio-deltaic, LST sandstones owing to effective meteoric water circulation, and (vi) formation of autochthonous glauconite, which is increases in abundance towards the top of the fluvio-deltaic, LST sandstones, and along TS, and in the shoreface, TST sandstones, by alteration of micas owing to the flux of seawaters into the sandstones during transgression, whereas parautochthonous glauconite is restricted to the TS sandstones owing to marine reworking. Mesogenetic alterations, which include cementation by quartz overgrowths and illite, display fairly systematic link to fluvio-deltaic, LST sandstones. This study has revealed that linking of diagenesis to transgression and regression events enables a better understanding of the parameters that control the spatial and temporal distribution of diagenetic alterations in sandstones and of their impact on reservoir quality evolution. 相似文献
889.
890.
针对采用定值相对极限位移判定隧道围岩稳定性时存在的问题,提出了采用模糊概率理论判定隧道围岩稳定的计算方法.结合厦门翔安海底隧道工程实际,利用曲线回归和模糊概率方法对海底隧道围岩稳定性概率进行了计算分析.参考现行规范并根据海底隧道各个开挖步的变形量综合确定极限相对位移上下限,采用指数函数对海底隧道CRD1部和CRD3部的拱顶下沉收敛曲线进行了回归分析.根据回归参数及实测结果,应用模糊概率公式对隧道围岩的稳定性概率进行了计算,从而为根据某个时刻的相对位移来判断海底隧道稳定性提供了参考. 相似文献