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221.
核电站温排水卫星遥感监测应用研究 总被引:1,自引:0,他引:1
选取我国 HJ-1 B卫星红外相机为遥感数据源,在介绍了温排水卫星遥感监测的技术流程和基本原理之后,重点论述了海表温度反演的算法和基准温度提取的基本原则。以2013年1月17日大亚湾核电站和2013年5月22日田湾核电站2景 HJ-1 B红外相机数据为应用实例,说明了卫星遥感监测可作为开展核电站温排水影响监测与热污染评价的首选技术方向和主要监测手段,阐述了其在核电站温排水影响后评估中的作用和意义。 相似文献
222.
223.
Alexei V. Uvarov 《Environmental monitoring and assessment》2000,60(3):337-357
Long-term charcoal production in small private charcoal kilns (CK) in Eastern Bieszczady Mts. (SE Poland) can cause local smoke contamination of the ambient forest environment. Responses of model soil systems, contaminated or not contaminated by CK smoke, to contrasting combinations of hydrothermic regimes were compared in laboratory microcosms (respiration of soil community, decomposition rate of soil organic matter and cotton stripes, herb seeds germination were studied). The majority of the obtained data show a markedly higher level of soil biological activity in the CK versus the control series. In some cases CK and control soil systems show different patterns of reactions to the tested combinations of microclimate regime. These phenomena should at least partly be attributed to the effects of CK pollution. 相似文献
224.
通过对乌鲁木齐市水磨沟区植被的现状调查和对存在问题的分析,结合生态示范区建设指标体系,提出提高该区植被覆盖率及改善生态环境的设想。 相似文献
225.
火力发电行业主要气态污染物排放量计算方法研究 总被引:1,自引:0,他引:1
针对目前我国火力发电行业气态污染物排放量计算方法使用混乱的情况,根据欧盟《空气污染物排放清单指南》和美国《空气污染物排放因子汇编》,介绍了火电行业主要气态污染物排放量的实际测量及理论计算方法。提出我国火电行业应根据实际情况,选择实际测量、排放因子或经验公式等方法计算污染物排放量;使用排放因子方法计算SO2排放量时,应开展S元素转化率的研究;火电厂应增加燃料中N元素的分析,以利于NOx排放量的准确估算。 相似文献
226.
火电厂自行监测关键问题研究 总被引:2,自引:0,他引:2
分析了我国火电厂自行监测的现状及存在的问题,包括监测指标不全、监测频次不足、监测点位代表性不够、信息公开不规范等。从监测方案和信息记录2个方面,针对废气、废水、厂界噪声、周边环境质量等的监测点位、监测指标和监测频次,以及监测信息、生产和污染治理设施运行状况、工业固体废物的记录要求,提出了相应的技术建议。 相似文献
227.
Using Multi-Scale Sampling and Spatial Cross-Correlation to Investigate Patterns of Plant Species Richness 总被引:8,自引:0,他引:8
Land managers need better techniques to assess exoticplant invasions. We used the cross-correlationstatistic, I
YZ, to test for the presence ofspatial cross-correlation between pair-wisecombinations of soil characteristics, topographicvariables, plant species richness, and cover ofvascular plants in a 754 ha study site in RockyMountain National Park, Colorado, U.S.A. Using 25 largeplots (1000 m2) in five vegetation types, 8 of 12variables showed significant spatial cross-correlationwith at least one other variable, while 6 of 12variables showed significant spatial auto-correlation. Elevation and slope showed significant spatialcross-correlation with all variables except percentcover of native and exotic species. Percent cover ofnative species had significant spatialcross-correlations with soil variables, but not withexotic species. This was probably because of thepatchy distributions of vegetation types in the studyarea. At a finer resolution, using data from ten1 m2 subplots within each of the 1000 m2 plots, allvariables showed significant spatial auto- andcross-correlation. Large-plot sampling was moreaffected by topographic factors than speciesdistribution patterns, while with finer resolutionsampling, the opposite was true. However, thestatistically and biologically significant spatialcorrelation of native and exotic species could only bedetected with finer resolution sampling. We foundexotic plant species invading areas with high nativeplant richness and cover, and in fertile soils high innitrogen, silt, and clay. Spatial auto- andcross-correlation statistics, along with theintegration of remotely sensed data and geographicinformation systems, are powerful new tools forevaluating the patterns and distribution of native andexotic plant species in relation to landscape structure. 相似文献
228.
Nabil Semmar Maurice Jay Muhammad Farman Maurice Roux 《Environmental Modeling and Assessment》2008,13(1):17-33
The quantitative assessment of plant diversity and its monitoring with time represent a key environmental issue for management
and conservation of natural resources. Assessment of plant diversity could be based on chemical analyses of secondary metabolites
(e.g. flavonoids, terpenoids), because of the substantial quantitative and qualitative between-individual variability in such
compounds. At a geographical scale, the plant populations become widely dispersed, and their monitoring from numerous routine
individual analyses could become restricting. To overcome such constraint, this study develops a multivariate calibration
model giving the relative frequency of a particular taxon from a simple high-performance liquid chromatography (HPLC) analysis
of a plant mixture. The model was built from a complete set of mixtures combining different taxons, according to an experimental
design (Scheffé’s matrix). For each mixture, a reference HPLC pattern was simulated by averaging the individual HPLC profiles
of the constitutive taxons. The calibration models, based on Bayesian discriminant analysis (BDA), gave statistical relationships
between the contributions of each taxon in mixtures and reference HPLC patterns of these mixtures. Finally, these models were
validated on new mixtures by using outside plants. This new biodiversity survey approach is illustrated on four chemical taxons
(four chemotypes) of Astragalus caprinus (Fabaceae). The more differentiated the taxon, the better predicted its contributions (in mixtures) were by BDA calibration
model. This new approach could be very useful for a global routine survey of plant diversity. 相似文献
229.
230.
Amy Hinsley Tamsin E. Lee Joseph R. Harrison David L. Roberts 《Conservation biology》2016,30(5):1038-1047
The wildlife trade is a lucrative industry involving thousands of animal and plant species. The increasing use of the internet for both legal and illegal wildlife trade is well documented, but there is evidence that trade may be emerging on new online technologies such as social media. Using the orchid trade as a case study, we conducted the first systematic survey of wildlife trade on an international social‐media website. We focused on themed forums (groups), where people with similar interests can interact by uploading images or text (posts) that are visible to other group members. We used social‐network analysis to examine the ties between 150 of these orchid‐themed groups to determine the structure of the network. We found 4 communities of closely linked groups based around shared language. Most trade occurred in a community that consisted of English‐speaking and Southeast Asian groups. In addition to the network analysis, we randomly sampled 30 groups from the whole network to assess the prevalence of trade in cultivated and wild plants. Of 55,805 posts recorded over 12 weeks, 8.9% contained plants for sale, and 22–46% of these posts pertained to wild‐collected orchids. Although total numbers of posts about trade were relatively small, the large proportion of posts advertising wild orchids for sale supports calls for better monitoring of social media for trade in wild‐collected plants. 相似文献