分散型生活污水水质研究

分散型生活污水水质是制定分散型污水处理装置设计规范、产品标准的基础.本文研究了分散型生活污水的水质特征、季节变化特性、与生活方式之间的关系等.在分散型污水处理装置的设计中应根据不同分散型污染源的水质特征选取设计参数,不应简单套用点源生活污水的水质指标.     

高校思想政治工作新探

在新形势下，高校思想政治工作面临着新情况、新问题，如：大学生的思想观念和价值取向发生了新的变化；大学生生活方式发生了新变化；大学生接受信息的渠道发生了新的变化等。高校思想政治工作者要不断提高思想工作的创新性和实效性，研究工作对策和方法，开拓高校思想政治工作的新局面。     

城市雕塑与城市环境

近年来，随着城市化进程加快，城市环境也在发生着日新月异的变化。转眼之间，城市雕塑遍布城市的各种广场、生活小区、园林公园、大小校园等公共场所，受到越来越多人的关注和喜爱。城市雕塑得到了迅速发展。     

西宁市生活垃圾现状及处理措施

西宁市生活垃圾污染已成为社会的一大公害,也是当前突出的环境问题之一.为了摸清西宁市生活垃圾的本底、日产量及成份构成等情况,为今后生活垃圾的消纳、处理提供科学依据,1989年西宁市将生活固体废物调查及处理对策研究列入2000年环境保护发展战略研究课题.本文就西宁市生活垃圾的排放历史、现状、对策等方面进行了分析、探讨.历史与现状解放初期和50年代,西宁市的生活垃圾(混杂部分工业废弃物)多数被就近填坑垫基,这一部分垃圾基本上已被覆盖在城市建筑物之下.还有一部分就近倾倒在湟水干流两侧.60年代,生活垃圾作为农肥运到近郊农村.最初农民欢迎,并主动到城内拉运,但随着生活垃圾成份的变化,污染物质越来越多,使土壤结构遭到破坏,土质下降,保肥、保水能力差,影响作物生长发育,并使作物病虫害增多,农作物产量和质     

浅析生活垃圾焚烧飞灰的环境管理

介绍了目前我国生活垃圾焚烧飞灰的产生情况及其环境影响;由于经济、技术等方面的原因,导致部分地区的生活垃圾焚烧飞灰在管理、利用及处理处置等方面存在着各种问题,从而造成二次污染;强调指出应该加强生活垃圾的源头管理,增加飞灰利用、处理处置能力,提高其利用、处理处置水平,改善飞灰管理不规范、利用技术水平有限和处理处置混乱的局面,避免造成二次污染,促进人类社会可持续发展.     

居民低碳消费行为及碳排放驱动因素的实证分析——基于杭州地区的调查

人为碳排放在碳减排中发挥着独特的作用,而实现低碳消费方式是促进碳减排的重要途径.基于杭州地区常住居民的调查数据,对样本居民的交通消费、生活能源消费和消费习惯等三个方面进行了行为比较,测算了居民的生活性能源碳排放量,并通过构建计量模型分析了居民碳排放的影响因素.其中,居民收入水平、最近一周是否使用过一次性产品、地域因素等对居民碳排放有着显著影响.以此为基础,提出了引导居民转变传统消费模式,提升低碳消费意识等政策依据.     

北部太湖DO、pH时空变化及其与叶绿素a的相关性分析

基于北部太湖贡湖、梅梁湾、竺山湖2013～2018年湖泛期逐日巡查数据和2013～2018年各月监测数据,采用频率曲线等方法分析了三湖湾溶解氧(DO)和pH的时空变化特征,利用相关分析法探讨了水体富营养化对DO和pH的可能影响.研究结果表明:(1)湖泛期多年平均DO竺山湖(7.41mg/L)＜梅梁湾(8.62mg/L)...     

饮用水源水库铁锰垂直分布规律及原因

经对水温分层型季节性缺氧水库铁、锰污染的研究表明,Fe、Mn分布随着季节变化、水库水温分层而变化,呈现明显的垂直分布规律:高浓度Fe、Mn主要出现在水温分层期水库中、下层,与库底缺氧、pH值下降、基岩溶蚀、沉积物高浓度Fe、Mn释放造成的二次污染等密切相关,从而为自来水厂实施优化分层取水和污染控制提供了依据.     

成都市大气颗粒物中多环芳烃分布规律的研究

前言随着现代生产的发展,人类的生活环境发生了很大的变化,进入环境的化学物质日益增多。目前已发现环境中存在着许多致癌物,其中最主要的一类化学物质是多环芳烃简称PAH,PAH化合物一般具有致癌性和致突变性.或具有诱发癌症的作用,PAH     

西北地区居民生活用电的影响因素分析

通过对西北地区的实地调查,运用多元线性回归模型分析了居民生活用电的影响因素。结果表明:人均收入和家庭人口是影响西北地区居民生活用电的主要因素;家庭对大功率电器的拥有情况在较高的程度上影响着其生活用电的水平;从农村到小城市、中等城市和大城市,居民生活用电量存在明显的阶梯变化特征,其结论为研究中国居民生活用电特征及电力的开发利用水平提供了依据。     

盐城沿海珍稀动物保护与经济发展的关系

江苏盐城沿海有我国至今仍保存较为完好的滩涂原生生态系统，栖息着３３０余种鸟兽资源，其中被列为我国重点保护的种类达５７种之多；然而，如何保护、发展和合理利用野生动物资源，力争做到既能维持生态平衡，又能促进经济发展，是我们今天所面临的新课题。本文对盐城沿海珍稀动物保护与经济发展的关系进行了探讨。     

伊宁市大气污染特征及变化浅析

通过对伊宁市2005年1月起空气自动监测系统正式运行以来的监测数据分析,归纳、总结伊宁市大气污染物随季节变化规律,每日、小时变化规律及市区不同地区大气污染物分布特征,并对这种特征及变化规律进行分析.     

Plant Diversity in Live Fences and Pastures,Two Examples from the Mexican Humid Tropics

This study analyzes the potential uses of live fences and pastures as reservoirs of plant diversity for two regions with different management histories, Los Tuxtlas (LT) and Uxpanapa (UX), Veracruz, México. We studied two habitats, live fences and pastures, analyzed their species richness, diversity, structure and plant composition and classified species according to plant regeneration modes (light-demanding and shade tolerant), seed dispersal syndrome and their local uses. We recorded 62 species of trees at LT and 48 at UX. Live fences were more diverse than pastures in both regions. The LT site showed to analyze the relationship a higher diversity of plants in regeneration stages than the one at UX. However, UX had higher diversity of adult plants in the pastures than LT. Composition and structure of live fences were different between regions, as well as within live fences and pastures, 53 % of species were light-demanding and 40 % were shade tolerant; 70 % of the species were dispersed by birds. Differences between sites are associated with the modifications in live fences structure, which changed according to managerial practices and the use of local species; this may influence plant regeneration modes as well as the visits of avian dispersal agents. In LT, all species found in live fences were useful to humans, whereas in UX, less than half were used by the local population. Our results underline the importance of live fences and isolated trees in pasture habitats as potential sites to host native and useful species from tropical rain forests in livestock landscapes.     

Phreatophytic Vegetation and Groundwater Fluctuations: A Review of Current Research and Application of Ecosystem Response Modeling with an Emphasis on Great Basin Vegetation

Although changes in depth to groundwater occur naturally, anthropogenic alterations may exacerbate these fluctuations and, thus, affect vegetation reliant on groundwater. These effects include changes in physiology, structure, and community dynamics, particularly in arid regions where groundwater can be an important water source for many plants. To properly manage ecosystems subject to changes in depth to groundwater, plant responses to both rising and falling groundwater tables must be understood. However, most research has focused exclusively on riparian ecosystems, ignoring regions where groundwater is available to a wider range of species. Here, we review responses of riparian and other species to changes in groundwater levels in arid environments. Although decreasing water tables often result in plant water stress and reduced live biomass, the converse is not necessarily true for rising water tables. Initially, rising water tables kill flooded roots because most species cannot tolerate the associated low oxygen levels. Thus, flooded plants can also experience water stress. Ultimately, individual species responses to either scenario depend on drought and flooding tolerance and the change in root system size and water uptake capacity. However, additional environmental and biological factors can play important roles in the severity of vegetation response to altered groundwater tables. Using the reviewed information, we created two conceptual models to highlight vegetation dynamics in areas with groundwater fluctuations. These models use flow charts to identify key vegetation and ecosystem properties and their responses to changes in groundwater tables to predict community responses. We then incorporated key concepts from these models into EDYS, a comprehensive ecosystem model, to highlight the potential complexity of predicting community change under different fluctuating groundwater scenarios. Such models provide a valuable tool for managing vegetation and groundwater use in areas where groundwater is important to both plants and humans, particularly in the context of climate change.     

Does Riparian Forest Restoration Thinning Enhance Biodiversity? The Ecological Importance of Large Wood

Intact riparian ecosystems are rich in biological diversity, but throughout the world, many have been degraded. Biodiversity declines, particularly of vertebrates, have led to experimental efforts to restore riparian forests by thinning young stands to accelerate creation of large diameter live trees. However, many vertebrates depend on large diameter deadwood that is standing as snags or fallen to the forest floor or fallen into streams. Therefore, we reviewed the sizes of deadwood and live trees used by different vertebrate species to understand which species are likely to benefit from different thinning treatments. We then examined how riparian thinning affects the long‐term development of both large diameter live trees and deadwood. To this end, we used a forest growth model to examine how different forest thinning intensities might affect the long‐term production and abundance of live trees and deadwood. Our results suggest that there are long‐term habitat tradeoffs associated with different thinning intensities. Species that utilize large diameter live trees will benefit most from heavy thinning, whereas species that utilize large diameter deadwood will benefit most from light or no thinning. Because far more vertebrate species utilize large deadwood rather than large live trees, allowing riparian forests to naturally develop may result in the most rapid and sustained development of structural features important to most terrestrial and aquatic vertebrates.     

The Impact of Different Grazing Periods in Dry Grasslands on the Expansive Grass <Emphasis Type="Italic">Arrhenatherum elatius</Emphasis> L. and on Woody Species

Dry grasslands are one of the most species rich and endangered types of vegetation in Europe. In the Czech Republic, dry grasslands are mainly of anthropogenic origin and were formed as a result of grazing after the clear-cutting of thermophilous oak woods. Gradual changes in the farming landscape throughout the 20th century, particularly in the 1960s, resulted in the abandonment of the relatively infertile habitats of dry grasslands. After abandonment, dry grasslands decline and degrade due to the gradual overgrowth of woody species and expansion of perennial tall grasses. In the year 2000, a grazing management program was introduced in the protected areas within the territory of Prague City to maintain the species diversity of dry grasslands. The responses of the expansive grass species, Arrhenatherum elatius L. and multiple woody species (especially, Prunus spinosa L.) to differences in grazing periods were monitored for over a decade. Grazing in spring through the end of June had the greatest impact on the reduction of A. elatius and woody species. Grazing in the height of summer through autumn did not reduce the cover of these plants, and may support the prosperity of both A. elatius and the woody species due to higher levels of nutrients.     

重庆华蓥山山脉药用植物资源调查研究

通过野外考察、标本采集、资料查阅整理及标本鉴定,对重庆华蓥山山山脉药用植物资源进行了调查.结果表明,重庆华蓥山共有药用植物240科1017属2251种(含变种和亚种),其中地衣植物5科8属11种、苔藓植物23科30属36种、蕨类植物40科82属190种、裸子植物9科17属25种、被子植物163科880属1989种.对其种类组成、分布、药用部位、疗效等进行了统计分析,对民间习用药物做了简要介绍,并对其开发利用提出了建议.     

Impact of crude oil pollution on species number and live standing herbaceous crop biomass

Summary The impact of crude oil spill on the number of plant species and the above-ground live standing crop biomass (AGLSCB) of a herbaceous plant community was assessed. The spillage had a devastating effect on the herbaceous community and especially on the component herbaceous annuals. At least 80–90% of the species were absent in the affected areas in comparison to nearby unaffected areas, most of these being annuals. Perennial species were generally less affected. The total herbaceous production for a period of 12 months in the polluted areas was 885.1 gm^–2 compared with 4860.7 gm^–2 for the unaffected areas. The average monthly production in the polluted areas was 73.8 gm^–2 compared with 405.0 gm^–2 for the unaffected areas.Dr Debojit Baruah is the senior author of this paper and he is a research scholar at Dibrugarh University. Dr Sarada K. Sarma is a Pofessor in the Botany Department of Guwahati University in Assam.     

2020年第一季度枣庄市PM2.5源解析的分析研究

为了评估分析枣庄市不同来源污染物排放强度削减与大气环境质量变化之间的关系,使用统计方法和正定矩阵因子分解法对枣庄市2020年第一季度大气污染变化特征和污染来源进行了解析,探究了枣庄市大气固体悬浮微粒浓度变化影响机制。结果表明:2020年第一季度PM2.5、PM10、NO2、SO2浓度较2019年同期显著下降,但枣庄市采暖季内社会活动造成的正常排放仍高于大气环境容量;受新冠疫情影响,2020年较2019年PM2.5源因子浓度削减最大的为机动车源(46.5%)和工业源(17.9%),应长期采取机动车减排、产业结构调整等措施,科学规划“十四五”大气污染防治。     

Effects of dredging on benthic diatom assemblages in a lowland stream

The objective of this study was to assess the effects of dredging on the structure and composition of diatom assemblages from a lowland stream and to investigate whether the response of diatom assemblages to the dredging is also influenced by different water quality. Three sampling sites were established in Rodríguez Stream (Argentina); physico-chemical variables and benthic diatom assemblages were sampled weekly in spring 2001. Species composition, cell density, diversity and evenness were estimated. Diatom tolerance to organic pollution and eutrophication were also analyzed. Differences in physico-chemical variables and changes in benthic diatom assemblages were compared between the pre- and post-dredging periods using a t-test. Data were analyzed using Principal Components Analysis (PCA), non-metric multidimensional scaling (MDS) ordination and cluster analysis. The effects of dredging in the stream involve two types of disturbances: (i) in the stream bed, by the removal and destabilization of the substrate and (ii) in the water column, by generating chemical changes and an alteration of the light environment of the stream. Suspended solids, soluble reactive phosphorus and dissolved inorganic nitrogen were significantly higher in post-dredging periods. Physical and chemical modifications in the habitat of benthic diatoms produced changes in the assemblage; diversity and species numbers showed an immediate increase after dredging, decreasing at the end of the study period. Changes in the tolerance of the diatom assemblage to organic pollution and eutrophication were also observed as a consequence of dredging; in the post-dredging period sensitive species were replaced by either tolerant or most tolerant species. These changes were particularly noticeable in site 1 (characterized by its lower amount of nutrients and organic matter previous to dredging), which showed an increase in the amount of nutrients and oxygen demand as a consequence of sediment removal. However, these changes were not so conspicuous in sites 2 and 3, which already presented a marked water quality deterioration before the execution of the dredging works.