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1.
根据利用计算机辅助制图在编制环境规划中的体会和经验,阐述它在环境规划中的应用。  相似文献   

2.
以水华蓝藻为研究对象,用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)技术对其进行测定分析并获得了蛋白质指纹图谱。对铜绿微囊藻标准株(NIES-843)样品通过3种前处理方法得到的质谱图进行对比,确定了质谱分析的样品前处理方法,建立了利用MALDI-TOF MS技术简便、快速检测水华蓝藻的方法。对在水华中出现的4种不同蓝藻进行MALDI-TOF MS分析,结果表明各种蓝藻具有其特征性波谱,可据此对水华蓝藻进行区分和鉴定。该方法快速、简便、精确、可程序化,具有广泛的应用前景。  相似文献   

3.
土地利用变化是蝴蝶多样性丧失的重要原因,为探究森林转变为茶园与菜园后蝴蝶多样性的变化特点,于2019年4—10月采用样线法在江苏宝华山逐月调查了上述3种土地利用类型下的蝴蝶多样性。调查结果显示,共监测到蝴蝶5科47属62种;森林的Shannon Wiener多样性指数、Margalef丰富度指数和Pielou均匀度指数均高于茶园和菜园,但Simpson优势度指数茶园最高;功能丰富度指数(Fric)、二次熵指数(RaoQ)都是森林显著高于其他2种土地利用类型,但菜园的Fric显著高于茶园;功能离散度指数(Fdiv)和功能均匀度指数(Feve)3种土地利用类型间无显著差异。蝴蝶群落物种和功能多样性与植被类型及其时空变化有明显的相关性,土地利用变化等人类活动对蝶类群落多样性有破坏作用。  相似文献   

4.
Benthic algal assemblages, water chemistry, and habitat were characterized at 25 stream sites in the Willamette Basin, Oregon, during low flow in 1994. Seventy-three algal samples yielded 420 taxa — mostly diatoms, blue-green algae, and green algae. Algal assemblages from depositional samples were strongly dominated by diatoms (76% mean relative abundance), whereas erosional samples were dominated by blue-green algae (68% mean relative abundance).Canonical correspondence analysis (CCA) of semiquantitative and qualitative (presence/absence) data sets identified four environmental variables (maximum specific conductance, % open canopy, pH, and drainage area) that were significant in describing patterns of algal taxa among sites. Based on CCA, four groups of sites were identified: streams in forested basins that supported oligotrophic taxa, such as Diatoma mesodon;small streams in agricultural and urban basins that contained a variety of eutrophic and nitrogen-heterotrophic algal taxa; larger rivers draining areas of mixed land use that supported planktonic, eutrophic, and nitrogen-heterotrophic algal taxa; and streams with severely degraded or absent riparian vegetation (> 75% open canopy) that were dominated by other planktonic, eutrophic, and nitrogen-heterotrophic algal taxa. Patterns in water chemistry were consistent with the algal autecological interpretations and clearly demonstrated relationships between land use, water quality, and algal distribution patterns.  相似文献   

5.
There are millions of small isolatedwetlands in the semi-arid Canadian prairies. These`sloughs' are refuges for wildlife in an area that isotherwise intensively used for agriculture. They areparticularly important as waterfowl habitat, with morethan half of all North American ducks nesting inprairie sloughs. The water levels and ecology of thewetlands are sensitive to atmospheric change and tochanges of agricultural practices in the surroundingfields. Monitoring of the hydrological conditions ofthe wetlands across the region is vital for detectinglong-term trends and for studying the processes thatcontrol the water balance of the wetlands. Suchmonitoring therefore requires extensive regional-scaledata complemented by intensive measurements at a fewlocations. At present, wetlands are being enumeratedacross the region once each year and year-roundmonitoring is being carried out at a few locations. Theregional-scale data can be statistically related toregional climate data, but such analyses cast littlelight on the hydrological processes and have limitedpredictive value when climate and land use arechanging. The intensive monitoring network has providedimportant insights but it now needs to be expanded andrevised to meet new questions concerning the effects ofclimate change and land use.  相似文献   

6.
This article investigates the relationship of local air pollution pattern with urban land use and with urban thermal landscape using a GIS approach. Ambient air quality measurements for sulfur dioxide, nitrogen oxide, carbon monoxide, total suspended particles, and dust level were obtained for Guangzhou City in South China between 1981 and 2000. Landsat TM images and aerial photo derived maps were used to examine city's land use and land cover at different times and changes. Landsat thermal infrared data were employed to compute land surface temperatures and to assess urban thermal patterns. Relationships among the spatial patterns of air pollution, land use, and thermal landscape were sought through GIS and correlation analyses. Results show that the spatial patterns of air pollutants probed were positively correlated with urban built-up density, and with satellite derived land surface temperature values, particularly with measurements taken during the summer. It is suggested that further studies investigate the mechanisms of this linkage, and that remote sensing of air pollution delves into how the energy interacts with the atmosphere and the environment and how sensors see pollutants. Thermal infrared imagery could play a unique role in monitoring and modeling atmospheric pollution.  相似文献   

7.
The condition of 25 stream sites in the Yakima River Basin, Washington, were assessed by the U.S. Geological Survey's National Water-Quality Assessment Program. Multimetric condition indices were developed and used to rank sites on the basis of physical, chemical, and biological characteristics. These indices showed that sites in the Cascades and Eastern Cascades ecoregions were largely unimpaired. In contrast, all but two sites in the Columbia Basin ecoregion were impaired, some severely. Agriculture (nutrients and pesticides) was the primary factor associated with impairment and all impaired sites were characterized by multiple indicators of impairment. All indices of biological condition (fish, invertebrates, and algae) declined as agricultural intensity increased. The response exhibited by invertebrates and algae suggested a threshold response with conditions declining precipitously at relatively low levels of agricultural intensity and little response at moderate to high levels of agricultural intensity. This pattern of response suggests that the success of mitigation will vary depending upon where on the response curve the mitigation is undertaken. Because the form of the community condition response is critical to effective water-quality management, the National Water-Quality Assessment Program is conducting studies to examine the response of biota to gradients of land-use intensity and the relevance of these responses to water-quality management. These land-use gradient pilot studies will be conducted in several urban areas starting in 1999.  相似文献   

8.
Due to human impact under climatic variations, western part of Northeast China has suffered substantial land degradation during past decades. This paper presents an integrated study of expansion process of salinized wasteland in Da’an County, a typical salt-affected area in Northeast China, by using Geographic Information Systems (GIS) and remote sensing. The study explores the temporal and spatial characteristics of salinized wasteland expansion from 1954 to 2004, and land use/cover changes during this period. During the past 50 years, the salinized wasteland in study area have increased by 135,995 ha, and in 2004 covers 32.31% of the total area, in the meantime grassland has decreased by 104,697 ha and in 2004 covers only 13.15% of the study area. Grasslands, croplands and swamplands were found the three main land use types converted into salinized wasteland. Land use/cover changes shows that between 1954 and 2004, 48.6% of grasslands, 42.5% of swamplands, and 14.1% of croplands were transformed into salinized wasteland, respectively. Lastly, the major factors influencing salinized wasteland expansion and land use/cover changes were also explored. In general, climatic factors supplied a potential environment for soil salinization. Human-related factors, such as policy, population, overgrazing, and intensified and unreasonable utilization of land and water resources are the main causes of salinized wasteland expansion.  相似文献   

9.
This paper examines the attitudes and perceptions of local people about ecological resources, environmental hazards, and future land use of the Idaho National Engineering and Environmental Laboratory (INEEL). Such monitoring of attitudes is an important aspect of environmental assessment. We interviewed 262 people who attended the 42nd Annual Free Fishermen's Breakfast at St. Anthony, Idaho, on 23 March 1997. We tested the null hypotheses that there were no differences in perceptions about ecological resources, hazards and future land use of INEEL as a function of gender, age, education, and place of residence. Dumping trash in the ocean and cutting rainforests rated as the environmental problems of highest concern, and ozone, radon and high voltage lines rated the lowest; cleaning up Department of Energy sites rated intermediate. Respondents were most willing to expend government funds to make drinking water clean. Three significant differences were found: 1) women rated environmental problems as more severe than did men, and women were more willing to expend federal funds to solve these problems, 2) respondents under 30 years of age rated environmental problems as more severe than older people, and they were more willing to spend money to solve them, and, 3) respondents who had not finished high school were more concerned with environmental problems and were more willing to spend money to solve them than respondents with a high school education. Maintaining INEEL as a National Environmental Research Park (NERP) rated as the most preferred future land use, followed by continued reprocessing of nuclear materials and hunting. Using INEEL for housing and additional nuclear waste storage rated the lowest. Men rated grazing livestock and additional nuclear waste storage higher than did women. In general, respondents from 30 – 49 rated several economic uses (hunting, grazing livestock, growing crops) higher than did people in other age groups. Respondents with some college rated these economic uses higher than did respondents who had not graduated from high school. These results indicate that respondents living around INEEL believe that INEEL should continue with a reprocessing and NERP mission, but that other peripheral uses, such as hunting, hiking and grazing, should be allowed on some of the land. These views should aid in environmental assessment of the site, and in developing further management plans for INEEL.  相似文献   

10.
We present evidence from studies oflakes in Killarney Park, Ontario, Canada that waterclarity is a key variable for monitoring theeffects of climate change, high UV exposure andacidification. In small oligotrophic lakes, thesestressors affect water clarity primarily byaltering the concentration of DOC in lake water. Clear lakes (<2 mg L-1 DOC) proved to be highlysensitive indicators of stressors, exhibiting largethermal and optical responses to small changes inDOC. Extremely clear (<0.5 mg L-1 DOC) acidic lakesshowed the effects of climate change and solarbleaching in recent decades. These lakes becamemuch clearer even though they were slowlyrecovering from acidification.  相似文献   

11.
Recent biological inventory data shows severe declines in freshwater mussel abundance and biodiversity in the Conasauga River Basin in Northwest Georgia, USA. Based on assessments of habitat conditions, mussel populations should be sustainable. We conducted a study of sediment and water quality to evaluate the impact of anthropogenic contamination on mussel populations. Permeable membrane devices (PMD), polar organic chemical integrative samplers (POCIS™), conventional water and sediment quality analyses, and stable nitrogen isotope ratio analyses (δ15N) of snails and sediments were used to assess sediment and water quality at target sites throughout the basin. Ambient concentrations of organic contaminants in water were well below any aquatic life criteria; concentrations of some nutrients were detected above aquatic life criteria levels. Most mussel species in the river are endangered or threatened; therefore, snails were collected for δ15N analyses. Mean δ15N values for snails collected at forested upper watershed sites (national forest areas) were significantly lower than δ15N values from snails in agricultural areas. δ15N values for raw cow manure and manure-treated soil were similar to δ15N values for snails collected in agricultural areas. Dissolved nitrate from water samples had elevated δ15N values similar to the upper range of δ15N values for snails in agricultural areas. Data, particularly stable nitrogen isotope data, indicates that a land use change from national forest land to agriculture alters nitrogen sources to the basin and snails. Implications of nutrient release on freshwater molluscan reproduction, growth, and survival are discussed.  相似文献   

12.
Modelled and measured indicator species ratios of O3/NOz, O3/NOy, H2O2/HNO3, HCNO/NOy for the Lower Fraser Valley were compared with VOC-NOx-O3 sensitivity threshold values reported in previous studies. Modelled region - specific indicator ratio thresholds derived from 50% NOx and 50% VOC reduction scenarios are provided. They show strongest agreement with the H2O2/HNO3 ratio values found elsewhere. A clear transition region for the LFV from VOC to NOx sensitivity could not be identified, but there is evidence that O3 concentrations in the western valley, dominated by metropolitan Vancouver, are VOC sensitive, and the more rural eastern valley O3 concentrations exhibit greater NOx sensitivity. The UAM-V Process Analysis utility was used to identify physical and chemical mechanisms which contributed to O3 formation and destruction and indicate the key importance of entrainment from elevated layers generated by the highly complex meteorological conditions in determining near surface O3 concentrations.  相似文献   

13.
The Screening Level Concentration (SLC) approach was used to derive Lowest Effect Level (LEL) and Severe Effect Level (SEL) concentrations for nine metals (As, Cr, Cu, Pb, Mo, Ni, Se, U and V) and three radionuclides (226Ra, 210Pb, and 210Po) released to the aquatic environment during the mining and milling of uranium ore. This method was chosen because it allowed for the best use of the considerable historical and current data collected for diverse purposes in the uranium mining and milling regions of Canada (20,606 data points used in the analysis). Except for Cr, all the LELs derived in this study using the weighted method and published sediment quality guidelines (SQGs) were highly reliable (> 85%) in predicting sites unimpacted by uranium mining/milling defined as sites where reductions in the abundance and species richness of benthic invertebrate communities were < 20%. The derived SEL values and corresponding published SQGs (with the exception of Ni) were not reliable predictors (≤60%) of severe impacts on benthic invertebrate communities when severe impacts are defined as a reduction in abundance and species richness ≥40%. Most of the severely impacted sites had sediment contaminant concentrations well below the SEL values. It is concluded that LELs derived using the weighted method can reliably be used in ecological risk assessments as concentrations below which adverse effects on benthic invertebrate communities are not expected. In contrast, it is recommended that SELs not be used in assessments of uranium mining/milling activities as concentrations above which adverse effects are anticipated.  相似文献   

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