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151.
GPS????????????????????????????????????????????????????????????????????????ó??淽?????????????????????????????EM?????????????????????????????????????????????????????Ч????????????μ?GPS?????????? 相似文献
152.
Wenjie Wang Hua Zheng Chao Xu Weiguo Jiang Yunhui Du Wei Wang Zhe Zhang Xiaofu Liu 《中国地理科学(英文版)》2014,24(1):71-82
Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China.In order to clarify the interrelation among key ecological zone plans,this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas(key ecological function areas,key regions of ecological service function,national nature reserves) and the research on ecological conditions,based on multi-scale ecological spatial theme information,which incorporates elements like ecologi-cal quality and type,and by the aid of spatial information analysis and GIS modeling.The results showed a contrastively fine spatial consistency with 68.8% of priority areas of biodiversity conservation overlapping with three key ecological areas.Although the envi-ronment in priority areas of biodiversity conservation were in good conditions,protection pressure is also increasing,powerful supervi-sion and protection should not be ignored.The environmental conditions in the overlapping areas,as a whole,were superior to those in the non-overlapping areas.Since two areas have different characteristics,targeted protection measures should be formulated based on this difference,which will be very important for biodiversity conservation in priority areas of biodiversity conservation. 相似文献
153.
In situ Microphytobenthic community dynamics were combined with laboratory measurement of predominant species by fluorescence methods to estimate the areal primary production. Field investigation of community dynamics of microphytobenthos (MPB) was conducted from August 2006 to August 2007 in intertidal flats of the Nakdong River estuary, Korea. MPB Biomass varied between 0.47 and 16.58 μg cm?3 in the surface 1 cm sediment, with two dominant diatom species, Amphora coffeaeformis and Navicula sp., occupying average 77.2 ± 14.9% of total number of MPB cells. The biomass was higher in the slightly muddy sand sites than that in the sand site, and showed different pattern of seasonal variation. The profile of vertical distribution of biomass was an exponential decrease trend with depth in sediments. The biomass proportions in the uppermost 3 mm were 57.6% and 37.8% with and without the presence of biofilm, respectively. The two dominant species were cultured in laboratory, and their photosynthetic parameters, rETRmax (relative maximum electron transport rate), α (light utilization coefficient) and E k (light saturation parameter) were derived from rETR (relative ETR)-irradiance curves by Imaging- PAM (pulse amplitude modulated) fluorometry. The rETR-irradiance curves showed no significant difference of photosynthetic activities between the two species. The areal potential production ranged from 0.74 to 2.22 g C m?2 d?1. 相似文献
154.
The microscopic organisms from sediments are classified into microbenthos and meiobenthos. The former groups are usually referred to protozoa, microalgae and bacteria, whereas the latter comprise micrometazoa defined by mesh-size. Micro- and meiobenthos have been suggested as being one complex and are characterized by their small size, relative short life spans, high turnover rate, and complicated trophic structure. The quantification of the exchange rate of carbon seems a prerequisite for understanding the processes regulating the trophic structure in this complex, where the basic interactions of micro- and meiobenthos include nutrition, competition, synergy and inhibition, etc. The ecological processes mediating the interactions between these groups are poorly understood and invite our attention to more detailed studies. In this paper, we summarize literature data to outline the interactions of the two major assemblages and discuss the main progress in benthic microbial food web. 相似文献
155.
Special primers were designed based on the sequence information of superoxide dismutase genes reported in the Iiterature and were used for RT-PCR and rapid amplification of cDNA ends(RACE) to clone Tegillarca granosaMn-superoxide dismutase gene successfully.The length cDNA of Tegillarca granosaMn-superoxide dismutase gene was of 635bp by including a 3'untranslated region(UTR)of 230bp and an open reading frame(ORF) of 4.5bp encoding a polypeptide of 135 amino acids. TheTegillarca granosaMn-superoxide dismutase gene shares 66%~73% homology with Mizuhopecteb yessoensis's,Danio rerio's,Xenopus Laevis's,Human's,Callinectes sapidus'sSOD CDS, while the corresponding amino acids shares 68%-78% homology and 80%~89% comparability. These indicate the SOD gene is high evolutional conservation in animals. 相似文献
156.
三维城市模型的研究与实践(英文) 总被引:3,自引:0,他引:3
The way we interact with spatial data has been changed from 2D map to 3D Virtual Geographic Environment (VGE). Three-dimensional
representations of geographic information on a computer are known as VGE, and in particular 3D city models provide an efficient
way to integrate massive, heterogenous geospatial information and georeferenced information in urban areas. 3D city modeling
(3DCM) is an active research and practice topic in distinct application areas. This paper introduces different modeling paradigms
employed in 3D GIS, virtual environment, and AEC/FM. Up-to-date 3DCM technologies are evolving into a data integration and
collaborative approach to represent the full spatial coverage of a city, to model both aboveground and underground, outdoor
and indoor environments including man-made objects and natural features with 3D geometry, appearance, topology and semantics.
Supported by the National Natural Science Foundation of China ( No. 40871212, No. 40671158), the Leading Academic Discipline
Project of Shanghai Educational Committee( No.J50104). 相似文献
157.
158.
陕西黄土高原人工林土壤干层及形成原因 总被引:1,自引:0,他引:1
1 Introduction Abroad, a lot of research on soil water removal, seeping and evaporation has been done (Ole, 1998; Rapp, 2000). A seeping model of soil water was suggested (Yuin, 1998) and it was known that water removal is very slow in the unsaturated zon… 相似文献
159.
长江三角洲城市带扩展对区域温度变化的影响 总被引:7,自引:0,他引:7
Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional cli- matic trend of temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing–Zhenjiang–Yangzhou, Suzhou–Wuxi–Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28–0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer>autumn>spring>winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal. 相似文献
160.
鲁北新生代隐伏火山岩及其石油地质意义 总被引:1,自引:0,他引:1
鲁北新生代隐伏火山岩可划分为3个喷发期6个亚期,9种火山岩岩石类型和同期侵入的辉绿岩。它们形成在近大陆边缘的板内裂谷型盆地,对于富有机质生油岩的沉积、各种储集体的形成、多种含油圈闭类型的形成以及有机质成熟向烃类转化都是非常有利的。作为储集岩主要有玄武安山岩、辉绿岩和湖底玄武质凝灰岩。储油空间主要为次生孔隙和裂缝。火山岩及其有关岩石在本区不仅形成了特殊的油气藏,而且还可作为盖层、封堵层、披复构造的基岩,因此对石油地质勘探有重要意义。 相似文献