Conservation and management-oriented ecological research in the coastal zone of Baja California, Mexico

This paper presents the main results of two studies of contrasting natural and man-induced conditions along the Pacific coast of Baja California (Mexico), based on the assumption that ecological insight can be obtained from man-induced modifications insofar as relevant activities are explicitly addressed as parts of the systems under study. The study is concerned with a fragmented coastal succulent-sage scrub and showed that several patches of different size and age may harbor as many species as non-fragmented areas, and that 83% of the original species assemblage persisted in the fragments, in which the invasion by opportunistic exotic species may not progress beyond certain limits. The study of dune-backed and urban-backed beaches showed a significantly greater abundance of the Snowy Plover (Charadrius alexandrinus) at the dune-backed beach, where a much more active back-shore feeding of adult birds and the only evidences of breeding occurred. Both studies refer to landscape features of regional concern and its results may be used in conservation management. The results on fragmented coastal succulentsage scrub may encourage alternative urban designs that keep patches of the original landscape, thus meeting existing requirements of low density urban development for most of the coastal succulent-sage scrub area. The evidence presented on the negative effects of dune destruction on the abundance, feeding and reproductive performance of a threatened bird species has a bearing on the topic of biodiversity management. It may also contribute to the conservation of the coastal dunes system.     

垃圾填埋场渗沥水污染及控制研究

通过现场调查和模拟试验的方法,对武汉市郭茨口垃圾填埋场氧化塘和垃圾填埋渗沥水的特性进行了调研,查明了渗沥水的污染特性、降解规律,及氧化塘的运行状况和塘内渗沥水的污染负荷、分布特点.并对武汉市土壤和民用煤灰对渗沥水的吸附和防渗能力进行了初步研究。     

Soil lead (Pb) in residential transects through Lubbock,Texas: a preliminary assessment

Residential lead (Pb) contamination, resulting from decades-long use of leaded gasoline and lead-based paint, is likely to be present in soils in most urban areas. A screening level sampling effort demonstrated that Lubbock, Texas, USA, like other cities of its age and size, has areas of elevated soil Pb. This effort was based on soil sampling performed on residential, commercial and thoroughfare properties. The focus of this study was to investigate that component of soil contamination due to combustion of leaded gasoline. Soils were collected from the 1–2 cm surface layer from street-side property borders, well away from buildings that might lead to soil contamination from leaded paint chips. All samples were analyzed for Pb after a 1 M HNO₃ mild extraction to determine the amount of bioavailable Pb. Two of three transects through the city demonstrated significant trends of decreasing Pb concentrations with distance from the city center, paralleling a decrease in developed property age. Peak soil Pb concentrations outside city development was 4.9 ± 0.6 mg/kg while the median concentration for the city was 35.4 mg/kg. Peak soil Pb concentrations in the city center ranged from 90.0 to 174.0 mg/kg and decreased exponentially to 6.0–9.0 mg/kg at the furthest terminus of the residential transects.     

北九州产业废物的处理

在日本,基于“有关废物处理和清理的法律”制定了废物分类、处理责任和处理基准等。北九州市是以重化学工业为中业发展起来的城市,由于其工业活动产生了大量的各种工业废物。因此北九州市制定了“工业废物处理计划”,有计划地综合性地对工业废物实施处理、资源化、减量化。为了今后全球范围的环境保护,工业废物的再利用、再资源化有待于进一步提高。现在,北九州市正围绕着这个课题进行着研究。      

有机垃圾处理机发酵工艺研究

叙述了新型有机垃圾处理机的结构特点,分析了有机垃圾处理的生物发酵过程,通过不同温度、搅拌频率和通风时间的发酵实验,根据发酵效果的不同确定最佳关键工艺参数,为有机垃圾处理机的进一步发展提供依据。     

城市河道水环境生态治理措施研究

近年来,城市化进程不断加剧,而生态环境也遭到了严重的破坏,特别是城市河道水环境的破坏,这也是当前急需解决的一项难题。在人们的日常生活和工作当中,水起着十分重要的作用,一旦城市河道出现问题,将会严重影响人们的正常生活,水资源的破坏是政府部门面临的主要困扰之一,也是阻碍城市经济发展的重要问题,为此,水利以及环保部门一定要采取措施进行解决,进而保证生态环境的发展。本文就城市河道水环境生态治理措施进行了深入分析和研究,以期为相关工作提供借鉴。     

原生态环境景观设计在城市公园的应用

人类文明的发展,不断地在改变地球的生态环境,我们赖以生存的环境正在逐渐恶化,在城市中生活的人们远离了自然,生活环境已经不再健康,雾霾、水污染以及绿化的减少,都严重影响着人类自身的发展。在意识到环境对人类社会发展的重要性之后,人们开始重视城市环境的改造,引入原生态环境景观,希望获得人类与自然的和谐与平衡,在这样的背景下城市公园的概念受到了广泛的关注,城市公园的景观设计开始追求原生态,综合考虑了对原生态环境的保护和利用,不断完善城市公园的设计,发挥原有自然环境的作用,让人工设计与自然天成融为一体,打造城市中心的绿肺,改善城市生态环境,维护人类社会生产生活与自然环境的平衡,为人类建设更为宜居的生活环境。     

新时代城市土壤环境监测点位布设应用的研究分析

新时期城市构造呈现多样性,加上城市化、工业化发展迅猛,城市的演变日新月异,如何对城市土壤环境监测点位布设的方法进行取舍是十分关键的,本文详细介绍了城市土壤环境监测点位布设的方法以及其应用的研究分析,希望能为我国城市土壤环境监测的相关研究提供参考。     

城市河道生态治理与环境修复

城市在不断发展的过程中会面临越来越多的外来人口,虽然可以促进城市经济迅速发展,但同时也对城市的生态环境造成严重的破坏。城市河道是生态环境的重要组成部分,城市河道可以有效防止城市发生内涝,为城市的发展保驾护航。近几年来,城市河道遭到的污染日益严重,其生态系统面临许多问题,为了完善城市河道的功能,就要对其生态系统进行修复,使其更好地发挥出作用。     

Different response of bacterial community to the changes of nutrients and pollutants in sediments from an urban river network

• Bacterial community varied spatially in sediments from the urban river network. • Key environmental factors shaping bacterial community were detected by RDA. • Bacterial co-occurrence networks changed at different levels of nutrient and metal. • Potential indicator species were selected to predict pollution risk in sediment. Microbial communities in sediment are an important indicator linking to environmental pollution in urban river systems. However, how the diversity and structure of bacterial communities in sediments from an urban river network respond to different environmental factors has not been well studied. The goal of this study was to understand the patterns of bacterial communities in sediments from a highly dense urbanized river network in the lower Yangtze River Delta by Illumina MiSeq sequencing. The correlations between bacterial communities, the environmental gradient and geographical distance were analyzed by redundancy analysis (RDA) and network methods. The diversity and richness of bacterial community in sediments increased from upstream to downstream consistently with the accumulation of nutrient in the urban river network. Bacterial community composition and structure showed obvious spatial changes, leading to two distinct groups, which were significantly related to the characteristics of nutrient and heavy metal in sediments. Humic substance, available nitrogen, available phosphorus, Zn, Cu, Hg and As were selected as the key environmental factors shaping the bacterial community in sediments based on RDA. The co-occurrence patterns of bacterial networks showed that positive interaction between bacterial communities increased but the connectivity among bacterial genera and stability of sediment ecosystem reduced under a higher content of nutrient and heavy metal in average. The sensitive and ubiquitous taxa with an overproportional response to key environmental factors were detected as indicator species, which provided a novel method for the prediction of the pollution risk of sediment in an urban river network.