检索结果-南通市图书馆

Spatial distribution regularity and influence factors of population density in the LRGR

Science Bulletin 2007年第S2期 90-97页

作者： SONG GuoBao~(1,2) LI ZhengHai~(1,3+) BAO YaJing~1 L HaiYan~4 GAO JiXi~3 WANG HaiMei~5 XU Tian~6 CHENG Yan~7 1 Institute of Bio-Resources and environment,college of Life Science,Dalian Nationalities university,Dalian 116600,china 2 college of Resources Science & Technology,Beijing Normal university,Beijing 100875,china 3 Innovation Base of Regional Ecology,Chinese Research Academy of environmental Sciences,Beijing 100012,china 4 Institute of agricultural Resources and Regional Planning,Chinese Academy of agricultural Sciences,Beijing 100081,china 5 inner mongolia Municipality Observatory,huhhot 010051,china 6 college of Life Science,inner mongolia university,huhhot 010021,china 7 college of ecological environment,inner mongolia agricultural university,huhhot 010018,china

Combining GIS measures and statistic methods,this paper selects the physiographic factors and climatic factors to study the influencing strength and its functional forms of all factors on population density in the *** addition,this paper simulates the status of population density distribution in the LRGR with the factors influencing the population density *** findings indicate the following circumstances:(1)All natural factors have influence on the spatial pattern of population density in the LRGR,but the influencing extent and forms are quite *** factors and traffic network density have great influence on population density,while such factors as temperature and precipitation have little influence on population *** relationship between the popula- tion density and the altitude and traffic network density assumes the negative and positive linear cor- relation trends,while the influence of water system density and slope appears to be the exponential function and logarithmic function separately.(2)The population is scattered throughout LRGR and takes on such features as integral scattering and local concentration because of the influence of natural ***,a high population density belt has been formed in the middle of LRGR,and a high population density patch comes into being in the south of LRGR.(3)There is a good linear re- gression relationship between population density and human activity index(HAI)in the LRGR,which reflects that population density can present the artificial disturbance on natural ecosystem in the LRGR. (4)The increase of population density leads to the decrease of NDVI index.

关键词： population density artificial disturbance vegetation coverage physiographic factor LRGR

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Analysis of land use change and its driving force in the Longitudinal Range-Gorge Region

引用

Science Bulletin 2007年第S2期 10-20页

作者： LI ZhengHai~(1,4+) SONG GuoBao~(1,2) L HaiYan~3 BAO YaJing~1 GAO JiXi~4 WANG HaiMei~5 XU Tian~6 CHENG Yan~7 1 Institute of Bio-Resources and environment,college of Life Science,Dalian Nationalities university,Dalian 116600,china 2 college of Resources Science & Technology,Baijing Normal university,Baijing 100875,china 3 Institute of agricultural Resources and Regional Planning,Chinese Academy of agricultural Sciences,Baijing 100081,china 4 Innovation Base of Regional Ecology,Chinese Research Academy of environmental Sciences,Beijing 100012,china s inner mongolia Municipality Observatory,huhhot 010051,china 6 college of Life Sciences,inner mongolia university,huhhot 010021,china 7 college of ecological environment,inner mongolia agricultural university,huhhot 010018,china

The research on land use degree,land use change rate as well as regional difference of various land use types in the southwest Longitudinal Range-Gorge Region(LRGR)has been carried out on the re- gional and county *** the view of social economy,we have also analyzed the driving mecha- nism of land use change and the corresponding spatial scopes of various driving forces in the research *** research result indlcetse that,on the regional scale,farmland,forest and grassland compose the main body of land use in the LRGR,and the structural change of land use shows that grassland declines sharply,farmland increases and forest keeps *** the county scale,the land use is characterized by that land use level is relatively low,and the land use degree,the comprehensive variation rate and the relative variation rate among different land use types still *** analysis,the land use changes in the LRGR are mainly driven by investment Intensity of manpower and physical resources,the social economic output level,the intensity of natural disasters disturbance and educa- tional level of ***,the regionalism exists in the influence scope of different driving force types.

关键词： land use land use degree land use change rate driving force Longitudinal Range-Gorge Region(LRGR)

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

引用

Science china(Life Sciences) 2007年第6期50卷 766-772页

作者： GAO Feng1, HOU XianZhi1 & LIU YingChun2 1 college of Animal Science and Animal Medicine, inner mongolia agricultural university, huhhot 010018, china 2 college of Biotechnology and Bioengineering, inner mongolia agricultural university, huhhot 010018, china college of Animal Science and Animal Medicine Inner Mongolia Agricultural University Huhhot China college of Biotechnology and Bioengineering Inner Mongolia Agricultural University Huhhot China

This study investigated the effects of hormonal status and metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth and development. One hundred mongolian ewes, synchro- nized for oestrus and mated, were divided into three groups and offered 0.175 MJME·kgw-0.75·d-1 (Re- stricted Group 1, RG1), 0.33 MJME·kgw-0.75·d-1 (Restricted Group 2, RG2) and ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the sup- ply of exogenous energy decreasing during late pregnancy, maternal body weight and net body weight loss in RG2 and RG1 were lower than those of CG (P0.05), but the GH concentrations in RG2 and RG1 were enhanced and there was significant difference between RG1 and CG on d 120 of gesta- tion (P0.05). However, the NEFA and FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 140 of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological and biochemical maternal reactions to restriction became worse, which sig- nificantly reduced the average lamb birth weight and daily growth rate of fetus in RG2 (P<0.05) and RG1 (P<0.01).

关键词： late pregnancy, restricted ewes, fetus, growth and development

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

引用

Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 Center for Agriculture Water Research, china agricultural university, Beijing 100083, china 2 Chinese-Israeli International Center for Research and Training in Agriculture, china agricultural university, Beijing 100083, china 3 Water Conservancy and Civil Engineering college, inner mongolia agricultural university, Hohhot 010018, china Center for Agriculture Water Research China Agricultural University Beijing China Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing China Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Landscape Change and its effect on the environment of Daqing City

引用

Progress in Natural Science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and environment Science, Harbin Normal university, Harbin 150080, china college of Resources environment & Tourism, Capital Normal university, Beijing 100037, china college of Economics and Management, Northeast agricultural university, Harbin 150030, china) college of Life and environment Science Harbin Normal University Harbin 150080 China college of Resources environment and Tourism Capital Normal University Beijing 100037 China college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Study on the spatial differences and its time lag effect on climatic factors of the vegetation in the Longitudinal Range-Gorge Region

引用

Science Bulletin 2007年第S2期 42-49页

作者： BAO YaJing~1 SONG GuoBao~(1,2) LI ZhengHai~(1,3) GAO JiXi~3 L HaiYan~4 WANG HaiMei~5 CHENG Yan~6 XU Tian~7 1 Institute of Bio-Resources and environment,college of Life Science,Dalian Nationalities university,Dalian 116600,china 2 college of Resources Science and Technology,Beijing Normal university,Beijing 100875,china 3 Innovation Base of Regional Ecology,Chinese Research Academy of environmental Sciences,Beijing 100012,china 4 Institute of agricultural Resources and Regional Planning,Chinese Academy of agricultural Sciences,Beijing 100081,china 5 inner mongolia Municipality Observatory,huhhot 010051,china 6 college of ecological environment,inner mongolia agricultural university,huhhot 010018,china 7 college of Life Science,inner mongolia university,huhhot 010021,china

This article analyzes the correlation of NDVI and two meteorological data including temperature and precipitation,and probes the spetial pattern of responding sensitivity of the vegetation to temperature and precipitation *** constructing the NDVIrindex,the relation between vegetation cover and land use in the Longitudinal Range-Gorge Region（LRGR）is *** conclusion is as follows:（1） The time lag effect that vegetation responds to temperature and precipitation change is ***- ferent regions have different delay time corresponding to maximum correlation *** to response time of precipitation and temperature combination,three kinds of temperature-precipi- tation forms are defined,namely,precipitation and temperature in the same time,precipitation prior to temperature and temperature prior to precipitation.（2）The spatial distribution of sensitivity,of which vegetation responses to temperature,is characterized by several high and low scattered correlation *** from temperature,two insensitive regions and two sensitive belts are formed to pre- sent the response of vegetation to precipitation.（3）The NDVIris constructed,which can perfectly re- flect the corresponding relationship between meteorological factors and land use condition in the LRGR.

关键词： land cover meteorological factors effect of time lag spatial correlation population density Longitudinal Range-Gorge Region(LRGR)

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Distribution　and　Transformation　of　Native　and　Added　Ni　Fractions　in　Purple　Soils　from　Sichuan　Province

引用

Pedosphere 1996年第2期6卷 183-192页

作者： TU CONG(college of Resources and environment,Southwest agricultural university,Chonyqiny 630716 china) college of Resources and environment Southwest Agricultural University Chongqing 630716 China

ＤｉｓｔｒｉｂｕｔｉｏｎａｎｄＴｒａｎｓｆｏｒｍａｔｉｏｎｏｆＮａｔｉｖｅａｎｄＡｄｄｅｄＮｉＦｒａｃｔｉｏｎｓｉｎＰｕｒｐｌｅＳｏｉｌｓｆｒｏｍ　ＳｉｃｈｕａｎＰｒｏｖｉｎｃｅＴＵＣＯＮＧ（ＣｏｌｌｅｇｅｏｆＲｅｓ... 详细信息

ＤｉｓｔｒｉｂｕｔｉｏｎａｎｄＴｒａｎｓｆｏｒｍａｔｉｏｎｏｆＮａｔｉｖｅａｎｄＡｄｄｅｄＮｉＦｒａｃｔｉｏｎｓｉｎＰｕｒｐｌｅＳｏｉｌｓｆｒｏｍ　ＳｉｃｈｕａｎＰｒｏｖｉｎｃｅＴＵＣＯＮＧ（ＣｏｌｌｅｇｅｏｆＲｅｓｏｕｒｃｅｓａｎｄＥｎｖｉｒｏｎｍ...

关键词：四川紫色土土壤原有镍添加镍重金属分布转移

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of genetic diversity and relationships within and between two breeds of duck based on microsatellite markers

引用

Progress in Natural Science:Materials International 2009年第11期19卷 1581-1586页

作者： Fei Wu~a,Yinghua Huang~a,Ying Ma~b,Shengqiang Hu~c,Jinping Hao~c,Ning Li~a a State Key Laboratory for Agrobiotechnology,china agricultural university,Beijing 100193,china b college of Animal Science and Veterinary Science,inner mongolia agricultural university,Hohhot 010018,china c Gold Star Duck Production Ltd.,Beijing 100076,china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China college of Animal Science and Veterinary Science Inner Mongolia Agricultural University Hohhot 010018 China Gold Star Duck Production Ltd. Beijing 100076 China

The genetic diversity of two natural populations(M,N) of Beijing duck(Anas platyrhynchos) and 11 artificially selected lines of Beijing duck(A,B,E-L,O) from china Gold Star Duck Production Ltd.,along with two Cherry Valley duck lines(C and D) from the British Cherry Valley Livestock Division,was evaluated using 18 microsatellite markers covering 16 linkage groups.A phylogenetic tree of the 15 populations of duck,formed of four main branches,was constructed from Nei’s DAgenetic *** mean genetic differentiation index(FST) in all loci,Nei’s standard genetic distance(Ds),and the genetic distance DAbetween the Beijing duck and the Cherry Valley duck were 0.075,0.143 and 0.142,*** results demonstrated a high degree of genetic similarity between the two breeds and supported the hypothesis that the Cherry Valley duck was derived from the Beijing *** FSTmatrix of seven clusters of Beijing duck suggested that the efficiency of selection was not significant to some extent and should be supplemented by marker -assisted selection.

关键词： Duck Microsatellite marker Genetic diversity Genetic distance

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effects of Different Rotational Grazing Time on the Plant Population of Desert Steppe

Effects of Different Rotational Grazing Time on the Plant Po...

引用

The 3rd Korea-china-Japan Joint Symposium on Grassland Agriculture and Livestock Production

作者： Yang Jing and Liu Hongmei college of Ecology and environment Science inner mongolia agricultural university Hohhot 010018 china

＜正＞The effects of different rotational grazing time on the main plant population characteristics of desert steppe were investigated in this *** main results were shown as follows:the height of Stipa breviflora in late grazing plot was more superior than that in early plot,and the coverage and density of Alliumpoly rrhizum presented an obvious advantage.

关键词： Rotational grazing time Biomass Desert Steppe

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

引用

Science china(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of Animal Science and Technology, china agricultural university, Beijing 100094, china 2 Vocational and Technologic college, inner mongolia Agriculture university, Baotou 014109, china 3 college of Veterinary Medicine, china agricultural university, Beijing 100094, china college of Animal Science and Technology China Agricultural University Beijing China Vocational and Technologic college Inner Mongolia Agriculture University Baotou China college of Veterinary Medicine China Agricultural University Beijing China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P782) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：