检索结果-南通市图书馆

The seasonal dynamics of geochemical characteristics of sediments in the impact zone of the fish farm(Lake Ladoga,Russia)

引用

Aquaculture and Fisheries 2023年第6期8卷 654-660页

作者： Artem Lapenkov Alina Guzeva Ksenia Zaripova Zakhar Slukovskii St.Petersburg Federal Research Center of the Russian Academy of Sciences(SPC RAS) Institute of Limnology of the Russian Academy of SciencesLaboratory of Geography and Hydrology9Sevastyanova St.St.Petersburg196105Russia Institute of the North Industrial ecology Problems of Kola Science Center of RAS Academgorodok Str.141Apatity184209Russia

This study focuses on the analysis of seasonal dynamics of physicochemical parameters(pH and Eh)and organic matter content in the sediments accumulated within the impact zone of the cage trout farm(Lake Ladoga,Russia).The Ladoga is the largest lake in Europe and there are more than 20 fish farms located in the northern part of the *** geochemical research is necessary for predicting the negative impact of the polluted sediments on both the cage fish and the aquatic *** sampling was conducted during various seasons of the year(February,June,August,October)which were characterized by the different fish feeding *** sediment cores were collected at 7 points,including the cage and reference sites(150 m and 600 m far from the farm).The results showed that the accumulation of organic material released from the studied fish farms was local and the wastes did not enter the sediments at the control ***,the accumulated organic layer can be compacted and partially mineralized during winter ***,strongly reducing conditions in sediments occur due to the accumulation of organic material and low rate of water exchange within the studied ***,there is a potential risk of formation of toxic gases and release of accumulated nutrients and metals from sediments to *** can have a negative impact on benthic and nekton organisms,in particular cage fish.

关键词： Sediments Organic matter Physicochemical parameters Fish farming Aquaculture Lake ladoga

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Precipitation Type Estimation and Validation in China

引用

Journal of Mountain Science 2014年第4期11卷 917-925页

作者： CHEN Ren-sheng LIU Jun-feng SONG Yao-xuan Qilian Alpine ecology & hydrology Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Inland River Ecohydrology Chinese Academy of Sciences

The results from three methods aimed at improving precipitation type(e.g., rain, sleet, and snow) estimation are presented and compared in this paper. The methods include the threshold air temperature(AT), threshold wet bulb temperature(WBT) and Koistinen and Saltikoff(KSS) *** graphs are plotted to acquire the threshold air temperature or the threshold wet bulb temperature using daily averaged air temperature, wet bulb temperature and precipitation data at 643 stations from 1961 to 1979(precipitation types are not labeled in the database from 1980 to present) in China. The results indicate that the threshold AT or WBT methods are not able to differentiate rain, sleet and snow in the most regions in China; sleet is difficult to differentiate from other precipitation types based on the two threshold methods. Therefore, one threshold AT and WBT method was used in this study to differentiate rain and snow. Based on GaussianKriging interpolation of threshold air temperature(T0and wet bulb temperature(Tw), the T0 and Tw contour lines and contour surfaces are calculated for ***, a comparison between the KSS, AT and WBT methods are provided in which the KSS method is calculated based on air temperature and relative humidity. The results suggest that the KSS method is more appropriate for water phase estimation than are the other methods; the maximum precision for rain and snow is 99% and 94%, respectively. The AT method performs better than the WBT method when the critical air temperature is 2°C.

关键词：降水类型中国估计空气温度湿球温度验证轮廓表面日平均气温

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

Comparative productivity of Prosopis cineraria and Tecomella undulata based agroforestry systems in degraded lands of Indian Desert

引用

Journal of Forestry Research 2009年第2期20卷 144-150页

作者： G. Singh division of Forest ecology Arid Forest Research Institute

Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria *** Tecomella undulata *** yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian *** competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental *** plots size were 16 m × 18 m(D1), 20 m × 18 m(D2) and 32 m × 18 m(D3) with tree densities of 208, 138 and 104 trees·ha-1 after June 2002, *** showed that tree height increased by 3% to 7% during June 2002 to June *** diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in *** and *** in two years *** increase in crown diameter was 9% to 18% in *** and 11% to 16% in *** growth was relatively greater in 2002 than in *** of *** increased linearly from D1 to D3 *** soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting *** of soil organic matters and NH4-N were the highest(p<0.05) in 0-25 cm soil *** was more beneficial than *** in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural *** yield of agricultural crop increased when density of tree species was appropriate(i.e., optimum tree density), though it varied with tree size and depended upon resource *** result indicated bio-economic benefits of optimum density of *** and *** over traditional practices of maintaining random trees in farming system in arid zones.

关键词： arid region crop yield land productivity soil water and nutrients tree growth

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

Distribution and Estimation of Aboveground Biomass of Alpine Shrubs along an Altitudinal Gradient in a Small watershed of the Qilian Mountains, China

引用

Journal of Mountain Science 2015年第4期12卷 961-971页

作者： LIU Zhang-wen CHEN Ren-sheng SONG Yao-xuan HAN Chun-tan Qilian Alpine ecology & hydrology Research Station Key Laboratory of Ecohydrology of Inland Basin Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

Shrublands serve as an important component of terrestrial ecosystems, and play an important role in structure and functions of alpine *** estimation of biomass is critical to examination of the productivity of alpine ecosystems, due to shrubification under climate change in past *** this study, 14 experimental plots and 42 quadrates of the shrubs Potentilla fruticosa and Caragana jubata were selected along altitudes gradients from 3220 to 3650 m a.s.l.(above sea level) on semi-sunny and semi-shady slope in Hulu watershed of Qilian Mountains, *** foliage, woody component and total aboveground biomass per quadrate were examined using a selective destructive method, then the biomass were estimated via allometric equations based on measured parameters for two shrub *** results showed that *** accounted for 1–3 times more biomass(480.98 g/m2) than ***(191.21 g/m2).The aboveground biomass of both the shrubs varied significantly with altitudinal gradient(P<0.05).Woody component accounted for the larger proportion than foliage component in the total aboveground *** biomass on semi-sunnyslopes(200.27 g/m2 and 509.07 g/m2) was greater than on semi-shady slopes(182.14 g/m2 and 452.89g/m2) at the same altitude band for *** and *** contrast, the foliage biomass on semi-shady slopes(30.50 g/m2) was greater than on semi-sunny slopes(27.51 g/m2) for two *** deceased with increasing altitude for ***, whereas *** showed a hump-shaped pattern with *** equations were obtained from the easily descriptive parameters of height(H), basal diameter(D) and crown area(C) for biomass of *** and *** the equations type and variables comprising of the best model varied among the species, all equations related to biomass were significant(P < 0.005), with determination coefficients(R2) ranging from 0.81 to *** allometric equations satisfied the requirements of t

关键词：地上生物量高山生态系统海拔梯度祁连山小流域中国陆地生态系统估算

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

Global variations in critical drought thresholds that impact vegetation

引用

National Science Review 2023年第5期10卷 180-193页

作者： Xiangyi Li Shilong Piao Chris Huntingford Josep Pe?uelas Hui Yang Hao Xu Anping Chen Pierre Friedlingstein Trevor F.Keenan Stephen Sitch Xuhui Wang Jakob Zscheischler Miguel D.Mahecha Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking University Key Laboratory of Alpine ecology and Biodiversity Institute of Tibetan Plateau ResearchCenter for Excellence in Tibetan Earth ScienceChinese Academy of Sciences UK Centre for ecology and hydrology CSIC Global Ecology Unit CREAF-CSIC-UAB CREAF Cerdanyola de Vallès Department of Biogeochemical Integration Max Planck Institute for Biogeochemistry Department of Biology Colorado State University Graduate Degree Program in ecology Colorado State University Department of Mathematics College of Engineering Mathematics and Physical SciencesUniversity of Exeter Laboratoire de Météorologie Dynamique Institut Pierre-Simon LaplaceCNRS-ENS-UPMC-XDépartement de GeósciencesEcole Normale Superieure Earth and Environmental Sciences Area Lawrence Berkeley National Laboratory Department of Environmental Science Policy&ManagementUniversity of California Berkeley Department of Geography College of Life and Environmental SciencesUniversity of Exeter Department of Computational Hydrosystems Helmholtz Centre for Environmental Research—Ufz Remote Sensing Centre for Earth System Research Leipzig University

Identifying the thresholds of drought that,if crossed,suppress vegetation functioning is vital for accurate quantification of how land ecosystems respond to climate variability and *** present a globally applicable framework to identify drought thresholds for vegetation responses to different levels of known soil-moisture deficits using four remotely sensed vegetation proxies spanning *** thresholds identified represent critical inflection points for changing vegetation responses from highly resistant to highly vulnerable in response to drought stress,and as a warning signal for substantial vegetation *** thresholds varied geographically,with much lower percentiles of soil-moisture anomalies in vegetated areas covered by more forests,corresponding to a comparably stronger capacity to mitigate soil water deficit stress in forested ***,those lower thresholds are detected in more humid ***-of-the-art land models,however,overestimated thresholds of soil moisture(*** drought impacts),especially in more humid areas with higher forest covers and arid areas with few forest *** on climate model projections,we predict that the risk of vegetation damage will increase by the end of the twenty-first century in some hotspots like East Asia,Europe,Amazon,southern Australia and eastern and southern *** data-based results will inform projections on future drought impacts on terrestrial ecosystems and provide an effective tool for drought management.

关键词： drought threshold inflection points vegetation response soil moisture drought impacts

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

Diversity of non-timber forest products in Cachar District, Assam, India

引用

Journal of Forestry Research 2014年第2期25卷 463-470页

作者： Shovan Dattagupta Abhik Gupta Manoranjan Ghose Department of ecology and Environmental Science Assam University Biological Sciences division Indian Statistical Institute

We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered （plant species Dipterocarpus turbinatus）, Vulnerable （plant species Aquillaria malaccensis）, Endangered （animal species Hoolock hoolock, Indotestudo elongata and Manis pentadactyla）, and Vulnerable （animal species Nilssonia hurum and Rusa unicolor）. The whole plant or animal and/or their various parts were used as food or medicine, in house construction, magico-religious activities and others. While some NTFPs were harvested throughout the year, others were harvested seasonally. A comprehensive NTFP policy, along with scientific measures for regen- eration, restoration and augmentation of NTFP-yielding plants and animals, would help in addressing the conflicting demands of conservation and livelihood in the forests of this area.

关键词： Non-timber forest product (NTFP) lndo-Burma biodiversity hotspot Assam IUCN red list diversity threatened taxa

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

A semi-physical sediment yield model for estimation of suspended sediment in loess region

引用

International Journal of Sediment Research 2017年第1期32卷 12-19页

作者： Wei Si Weimin Bao Peng Jiang Liping Zhao Simin Qu Business School of Hohai University College of hydrology and Water Resources Hohai University division of Hydrologic Sciences Desert Research Institute

Sediment yield is a complex function of many environmental factors including climate,hydrology,vegetation,basin topography,soil types,and land *** present a new semi-physical watershed sediment yield model for the estimation of suspended sediment in loess *** model is composed by three modules in slope,gully,and stream *** slope sediment yield,a balance equation is established based on the concept of hydraulic erosion capacity and soil erosion resistance *** to the statistical analysis of watershed characteristics,we use an exponential curve to approximately describe the spatial variability of watershed soil erosion resistance *** gully phase,the relationship between gully sediment concentration and flow velocity is established based on the Bagnold’ stream power *** the stream phase,we assume a linear dependence of the sediment volume in the reach on the weighted sediment input and *** proposed sediment yield model is operated in conjunction with a conceptual hydrologic model,and is tested over 16 regions including testing grounds,and small,medium and large watersheds in the loess plateau region in the mid-reach of Yellow *** results indicate that the model is reasonable in structure and is able to provide a good simulation of sediment generation and transportation processes at both flood event scale and inter-annual time *** proposed model is generally applicable to the watersheds with soil texture similar to that of the loess plateau region in the Yellow River basin in China.

关键词： Hydraulic erosion capacity Erosion resistance capacity Sediment yield Suspended sediment Loess region

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

Interspecific competition, hybridization, and reproductive isolation in secondary contact： missing perspectives on males and females

引用

Current Zoology 2018年第1期64卷 75-88页

作者： Sara E. LIPSHUTZ Department of ecology and Evolutionary Biology Division of Biology University of Tennessee KnoxvilleTennessee 37996 USA

Research on sexual selection and hybridization has focused on female mate choice and male-male competition. While the evolutionary outcomes of interspecific female preference have been well explored, we are now gaining a better understanding of the processes by which male-male competition between species in secondary contact promotes reproductive isolation versus hybridization. What is relatively unexplored is the interaction between female choice and male competition, as they can oppose one another or align with similar outcomes for reproductive isolation. The role of female-female competition in hybridization is also not well understood, but could operate similarly to male-male competition in polyandrous and other systems where costs to heterospecific mating are low for females. Reproductive competition between either sex of sympatric species can cause the divergence and/or convergence of sexual signals and recognition, which in turn influences the likelihood for interspecific mating. Future work on species interactions in secondary contact should test the relative influences of both mate choice and competition for mates on hybridization outcomes, and should not ignore the possibilities that females can compete over mating resources, and males can exercise mate choice.

关键词：竞争男性杂交女性繁殖种间配偶选择失踪

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stable Isotopes in Precipitation in Xilin River Basin,Northern China and Their Implications

引用

Chinese Geographical Science 2012年第5期22卷 531-540页

作者： WU Jinkui DING Yongjian YE Baisheng YANG Qiyue HOU Dianjiong XUE Liyang Laboratory of watershed hydrology and ecology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Qilian Shah Station of Glaciology and Ecologic Environment State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Institute for Landscape ecology and Resources Management Justus-Liebig-University Giessen Giessen 35392 Germany Gansu Province Exploration Institute of Coal Geology Lanzhou 730000 China College of Earth and Environmental Science Lanzhou University Lanzhou 730000 China

Under the increasing pressure of water shortage and steppe degradation,information on the hydrological cycle in steppe region in Inner Mongolia,China is urgently *** intensive investigation of the temporal variations ofδD andδ1 8O in precipitation was conducted in 2007-2008 in the Xilin River Basin,Inner Mongolia in the northern ***δD andδ1 8O values for 54 precipitation samples range from+1.1‰to-34.7‰and-3.0‰to -269‰,*** wide range indicates that stable isotopes in precipitation are primarily controlled by different condensation mechanisms as a function of air temperature and varying sources of *** relationship between δD andδ1 8 O defined a well constrained line given by δD =7.89 δ18O+9.5,which is nearly identical to the Meteoric Water Line in the northern *** temperature effect is clearly displayed in this *** results of backward tra- jectory of each precipitation day show that the vapor of the precipitation in cold season(October to March)mainly originates from the west while the moisture source is more complicated in warm season(April to September).A light precipitation amount effect existes at the precipitation event scale in this *** vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation with lower d-excesses from a monsoon source from the southeastern China.

关键词：中国北方地区降水事件锡林河流域稳定同位素水汽来源空气温度水资源短缺降水量效应

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

A framework for quantifying properties of 3-dimensional movement-based signals

引用

Current Zoology 2010年第3期56卷 327-336页

作者： Shaun TD NEW Richard A PETERS ARC Centre of Excellence in Vision Science Division of EvolutionEcology & GeneticsResearch School of BiologyThe Australian National University

Understanding how signal properties are optimized for the reliable transmission of information requires accurate descriptionof the signal in time and space. For movement-based signals where movement is restricted to a single plane, measurementsfrom a single viewpoint can be used to consider a range of viewing positions based on simple geometric ***, considerations of signal properties from a range of viewing positions for movements extending into three-dimensions(3D) are more problematic. We present here a new framework that overcomes this limitation, and enables us to quantify the extentto which movement-based signals are view-specific. To illustrate its application, a Jacky lizard tail flick signal was filmed withsynchronized cameras and the position of the tail tip digitized for both recordings. Camera alignment enabled the construction ofa 3D display action pattern profile. We analyzed the profile directly and used it to create a detailed 3D animation. In the virtualenvironment, we were able to film the same signal from multiple viewing positions and using a computational motion analysisalgorithm (gradient detector model) to measure local image velocity in order to predict view dependent differences in signalproperties. This approach will enable consideration of a range of questions concerning movement-based signal design and evolutionthat were previously out of reach [Current Zoology 56 (3): 327-336, 2010].

关键词：信号特性三维运动框架量化几何计算属性依赖信息传输变动范围

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：