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1.
通过15年的红壤稻田长期定位试验,研究了不同施肥模式下土壤微生物生物量磷(MB-P)对土壤有机碳和磷素变化的响应.结果表明红壤稻田有机碳源的长期投入和土壤有机碳的逐年升高使土壤微生物生物量碳(MB-C)维持在较高水平(>800 mg·kg-1),是稻田土壤MB-P(>16.0 mg·kg-1)提高的主要原因.长期不施磷肥条件下,土壤全磷含量与试验前相比显著降低(P<0.05),而土壤有机磷含量平均提高了29.3%;土壤亏损的磷形态主要是无机磷(Al-P、Fe-P、Ca-P和O-P),其中Al-P含量处于最低水平(平均0.5 mg·kg-1).另外,长期不施磷肥土壤的MB-P远高于Olsen法提取态磷(Olsen-P)(<7.0 mg·kg-1),而稻田土壤MB-P与Al-P呈显著相关(P<0.05),表明土壤微生物对稻田土壤Al-P、Fe-P、Ca-P和O-P的利用是促进其向有效磷方向转化的关键途径.磷肥配合有机养分循环利用不仅提高了土壤磷库的积累,而且通过土壤微生物的活化有效地提高了土壤磷的有效性.  相似文献   

2.
污染生态化学:现状与展望   总被引:8,自引:14,他引:8  
随着生态学和环境化学的发展和交叉,形成了一门新的学科-污染生态化学。目前,它的主要研究内容包括化学污染物的迁移转化及其微观生态化学过程、化学污染的生态效应与毒理及生态风险评价、全球变化的生态化学、生态系统中化学污染物的分析与监测和污染控制生态化学等5个方面。在知识创新的科学目标指导下,污染生态化学今后的工作必须加强从理论上进行突破,在对基础研究进行深入的同时,应该特别注意开展一些应用研究,从而实现  相似文献   

3.
以珠海竹银水库为对象,针对水库面临的入库污染问题,分析入库主要的污染物类型与污染负荷总量,全面评估水库的污染现状,并对水库水环境容量状况进行评价.研究结果表明,入库河流的主要问题是氮、磷浓度较高,但其它污染物的浓度不高.每种污染物的水环境容量值都很大,其中氯化物的容量最大,重金属的容量较小,表明水库蓄水初期水质较好,纳污能力较强.这些结果为今后竹银水库的污染控制与水质管理,为实现安全供水目标提供基础数据.  相似文献   

4.
污水处理工艺的生态安全性研究进展   总被引:1,自引:0,他引:1  
杨赛  华涛 《应用生态学报》2013,24(5):1468-1478
污水经处理后,排放和回用时常规指标通常都能达到设计标准,但出水水质并未达到无害化.从可持续发展的角度来讲,为保障生态环境及人群的安全,需要将污水的综合毒性纳入排放标准.为此,在工艺的选择及优化时应将毒性削减效果纳入其中,提高污水处理工艺的生态安全性.本文着重综述了以特定污水处理为目的、以污水回用为目的及以受纳水体安全为目的各类污水处理工艺的生态安全性研究,指出传统生物处理与高级氧化技术相结合,在去除污染物质的基础上可以强化对毒性的削减;对于以污水回用为目的处理工艺,对各种工艺进行集成可实现常规污染物去除和毒性削减的优势互补;以受纳水体生态安全为目的的污水处理工艺,应重点基于工艺运行参数和工艺单元选择进行毒性削减优化.最后对研究中存在的问题以及未来的学科发展方向提出了建议.  相似文献   

5.
区域生态风险评价的关键问题与展望   总被引:10,自引:0,他引:10  
区域生态风险评价具有多风险因子、多风险受体、多评价终点、强调不确定性因素以及空间异质性的特点,它与传统的生态风险评价在风险源、胁迫因子和评价尺度上具有明显区别。尝试建立了一个基于陆地生态系统的区域生态风险评价框架,同时针对目前区域生态风险评价的研究现状,指出不确定性分析、尺度外推难、评价指标不统一、评价标准不统一、风险因子筛选及优先排序、区域内污染物复合、水生过渡到陆生生态系统风险评价、特殊的人为因素等是目前区域生态风险评价存在的关键问题及难点所在,并提出解决这些问题可能所需的工具、手段和理论方法突破。最后指出区域生态风险观测与数据采集加工、区域生态风险指标体系的统一与整合、区域生态风险评价方法论、区域生态风险的空间分布特征与表达以及区域生态风险评价反馈与管理机制5个方面是区域生态风险评价未来的研究重点。  相似文献   

6.
医用微生态调节剂现状与展望   总被引:1,自引:0,他引:1  
陈延祚教授于 2 0 0 0年 10月在《中国微生态学杂志》发表文章题为 :我国人用微生态制剂出路何在 ?文章中体现忧患意识 :a.在大量保健品中 ,民众认可只有酸奶一种 ,虽酸奶市场一片繁荣 ,但厂商为弱势企业。b.药用中仅有益生菌制成的粉剂和胶囊片剂。 c.医务界认为这种制剂见效慢 ,疗效不肯定 ,不如抗生素应手。他建议 :a.生产工艺要先进 ,操作要严守规则 ,保证产品质量稳定。 b.基础理论研究要提出适应症 ,有坚实的试验数据。 c.临床验证要严格对照 ,结果要可信、可靠。d.不要追求不切实际的做法 ,任意夸大功效 ,扩大适应症。 e.不要抄袭外…  相似文献   

7.
污染生态学研究的回顾与展望   总被引:29,自引:5,他引:29  
自20世纪70年代开始,伴随着我国环境科学的兴起和应用生态学的发展,污染生态学经历发生、成长、发展和壮大等几个历史阶段。已经形成了具有自己学科特色的理论体系和研究方法论,如今,污染生态学已成为研究生物系统与被污染环境之间相互作用规律及采用生态学原理对污染环境进行控制与修复的一门独立科学,是应用生态学的重要组成部分,是生态学与环境科学相互融合,相互交叉的产物,在新世纪的头20年中,污染生态学面临着新的机遇和挑战,它将在复合污染生态学,污染生态过程研究、污染生态毒理学和污染生态修复等分支领域和科学前沿取得重要进展和突破。  相似文献   

8.
水环境生态安全与一个区域生态系统的良性循环息息相关。为了对陕西省水环境生态安全水平进行合理评价,结合陕西省水生态现状,基于DPSBR概念模型构建水生态安全水平评价体系,采用SPA-MC(集对分析—马尔科夫链)耦合模型对陕西省2000—2017年水环境安全状况进行了动态评价,并提出适应性建议。结果表明:陕西省2000—2017年水环境生态安全水平整体上呈现先升高后降低的趋势,2001—2010年明显升高,2011—2017年降低;2010—2012年安全水平最高,为“较安全”水平, 2001、2002年安全水平最低,为“较不安全”水平;层级水平上,“生态压力”和“生态基础”对陕西省水环境生态安全水平的影响最大,指标水平上“水资源开发利用率”与“水土保持面积”的影响最大;预测陕西省2018—2025年水环境生态安全水平将长期处于“临界安全”状态,且逐步向“较安全”水平转变。重视水土保持工作和水污染防治工作,是持续改善陕西省水环境生态安全状况的重要举措。研究成果对陕西省水环境的有效保护以及生态建设政策的制定具有指导意义。  相似文献   

9.
乐安江沉积物中金属污染的潜在生态风险评价   总被引:114,自引:3,他引:114  
选择污染严重的乐安江河流沉积物为对象,利用风险因子E和风险指数RI等定量诊断工具开展沉积物中重金属污染的潜在生态风险评价。根据风险指标体系和空间分异规律,将流域划分居不同特征的4种生态风险功能区。对比评价效果。潜在生态风险评价与地积累 情况大同小异,可以相互补充和借鉴。  相似文献   

10.
复合污染生态毒理效应的定量关系分析   总被引:38,自引:0,他引:38  
采用全生育期土培毒性试验、全生育期水培毒性试验、陆生生态毒性试验、水生生态毒性试验和DGGE(denaturing gradient gel electrophoresis)指纹图谱分析等方法, 以乙草胺-Cu和Cd-Zn两组污染物为代表, 分别对小麦(Triticum aestivum)、水稻(Oryza sativa)、赤子爱胜蚓(Eisenia foetida)、对虾(Penaeus japonicus)及土壤微生物等以水、土壤为环境介质进行复合污染暴露, 并结合污染现场进行较为系统的定量分析. 结果发现: 污染物本身的化学性质对复合污染生态效应所起的作用, 要比其浓度组合关系的影响小得多; 污染物暴露的浓度组合关系更为直接, 在一定条件下甚至起决定作用; 复合污染生态效应还与生物种类, 特别是生态系统类型有关, 也与这些污染物作用的生物部位有关.  相似文献   

11.
The extensive input of chemical insecticides for pest control is considered as a serious risk to the environment, and the ecological disturbance of chemical insecticides has both positive and negative effects on complex agro-ecosystems. This paper proposed an indicator based on ecological two-sidedness theory and Shannon entropy, which is intended for analyzing informational complexity in a decision network of the chemical insecticide pollution management. The results indicated that the order of the value of RCC/CP index (where the RCC/CP index matrix WCC/CP is defined as the index optimization matrix of comprehensive cost divided by the index optimization matrix of comprehensive profit) for three insect pest-controlling strategies in scallion fields was “applying frequency vibration lamps and environment-friendly insecticides 8 times” (0.8714) < “applying trap devices and environment-friendly insecticides 9 times” (0.8858) < “applying common insecticides 15 times” (0.9077). The treatment “applying frequency vibration lamps and environment-friendly insecticides 8 times” was recognized as the optimal strategy for chemical insecticide pollution management in scallion fields in Shanghai, China. The results demonstrate that our proposed ecological indicator might arouse the interest of policy makers and eco-environmentalists who seek to minimize the use of chemicals, and the farmers who hope to optimize pest-controlling strategies in practice.  相似文献   

12.
铝的生态与健康风险研究进展   总被引:10,自引:0,他引:10  
张凯松  周启星 《生态科学》2003,22(4):351-355
人为原因加快了铝进入环境的速度,也加剧了铝对生命组分的毒害作用与危害。本文从毒理生态学、分子生态学等不同角度分析了铝对环境的生态风险和对人类的健康风险,概述了有关铝生态风险与健康风险两个方面的最新研究进展,对控制、消除环境中铝毒的发生提出了展望。  相似文献   

13.
阿特拉津生态风险及其检测和修复技术研究进展   总被引:54,自引:2,他引:54  
随着农药等化学品在农业生产上的广泛应用,它们所带来的生态与环境问题日益严重。在世界许多国家和地区的地表水和地下水中以及大气沉降物中检测出了阿特拉津的残留物,它对生态环境的影响具有全球性。阿特拉津在土壤中的持留期较长并具有生物蓄积性,对粮食和食品安全构成潜在威胁。动物试验结果表明,阿特拉津具有生物活性,因此深入研究阿特拉津的生态风险问题是当务之急。文中提出了有关阿拉津生态风险研究的一些观点。随着各种检测分析手段的发展,阿特拉津的检测技术日臻成熟,为研究阿特拉津生态风险创造了有利条件。阿特拉津的生物修复技术已被高度重视。  相似文献   

14.
农业生态安全及其生态管理对策探讨   总被引:20,自引:5,他引:20  
对生态安全和农业生态安全的基本内涵进行了探讨。认为生态安全是指不同尺度的生态系统及其生物要素、环境要素、资源要素等在数量、质量及其相互作用关系上的一种和谐、健康、稳定的状态和水平。农业生态安全包括农业环境安全、农业资源安全、农业生物安全和农业产品安全等几个方面的内容。提出了一系列农业生态安全管理对策 ,包括 :①加强农业生态安全管理 ,发展生态产业 ;②加强对现有资源与生态系统的保护、培育与可持续利用 ;③保护农业生物多样性 ,保障生物安全 ;④加强农业综合抗灾能力建设 ;⑤加强农业生态安全监测与法律法规体系建设 ;⑥建立良好的、和谐的社会、经济和政治关系。  相似文献   

15.
不同生态环境中中国猪种的遗传多样性研究   总被引:3,自引:1,他引:2  
采用最小二乘法研究了中国部分地方猪种血液蛋白质Tf、Am、Pa和Cp位点基因频率与生态环境之间的关系及其变化规律。结果表明,Tf、Am和Cp位点分别被检测出存在3个等位基因,而Pa位点存在2个等位基因。4个位点的各种基因频率在不同猪种类型和生态区域之间均表现出显着差异(P<0.05),显示出地理区域和生态类型对4个位点的基因频率和杂合度有明显的影响。洞庭-洪湖区-新安江-鄱阳湖区-太湖流域是各位点基因频率高低变化的起点.  相似文献   

16.
对淤泥湖水生植被的天然恢复过程、群落组成、结构、功能与动态等进行了定位研究(1992~1995).该湖水生植物共有20科29属41种.4种生活型的植物种类在该湖均有分布,以沉水草本(15种)和挺水草本(13种)为多.8个分布区类型中世界广布成分16种和东亚成分10种.群落结构包括层次结构和层片结构.该彻共有8个群落类型;群落现存量3208.8g·m-2,全湖植被资源贮量为16365.2t.  相似文献   

17.
运用生态学和经济学理论,对大山村经果林的主要经营模式进行调查研究.结果表明,柑桔(9年生)-茶叶,柿(5年生)-马铃薯-西瓜,梨(7年生)-马铃薯-大豆,梨(7年生)-桔梗,具有明显的生态、经济和社会效益.纯收益分别达8 700.00、12 351.00、12 337.50和22 500.00元·hm-2,均高于仅种农作物.林内郁闭度0.3~0.4,光能利用率比纯林提高了20%~30%.  相似文献   

18.
Currently, heavy metal (HM) contamination in greenhouse soils is a significant concern due to the rapid expansion of greenhouse agriculture. However, it is difficult to accurately assess HM pollution in greenhouse soils in China due to the lack of local geochemical baseline concentrations (GBCs) or corresponding background values. In the present study, the GBCs of HMs in Dongtai, a representative greenhouse area of China, were established from subsoils using cumulative frequency distribution (CFD) curves. The pollution levels of HMs and potential ecological risks were investigated using different quantitative indices, such as geo-accumulation index (Igeo), pollution index (PI), pollution load index (PLI) and ecological risk index (RI), based on these regional GBCs. The total concentrations of six metals (Cd, Cr, Cu, Ni, Pb and Zn) in surface soils were determined and shown to be lower than the concentrations reported in other greenhouse regions of China. The GBCs of Cd, Cr, Cu, Ni, Pb and Zn were 0.059–0.092, 39.20–54.50, 12.52–15.57, 20.63–23.26, 13.43–16.62 and 43.02–52.65 mg kg−1, respectively. Based on this baseline criterion, Cd, Pb and Zn accumulated in the surface soils because they were present at concentrations higher than their baseline values. The soils were moderately polluted by Cd according to the Igeo values, and the PI results indicated that moderate Cd contamination was present in this area. The large variation of Igeo value of Cd revealed that Cd in this area was likely influenced by agricultural activities. The PLI showed that most of the study area was moderately polluted. However, an analysis of the RI showed that the investigated HMs had low ecological risks. Correlation analysis and principle component analysis suggested that the Cd, Pb and Zn in the greenhouse soils mainly originated from anthropogenic sources (agricultural activities, atmospheric deposition etc.), while Cr, Cu, and Ni originated from natural sources. The findings of this study illustrated the necessity of GBC establishment at the local scale to facilitate more accurate HM evaluation of greenhouse soils. It is advisable to pay more attention to Cd, which could cause environmental problems in the greenhouse system.  相似文献   

19.
Aquatic oligochaetes are abundant in polluted areas and are, therefore, commonly used as bioindicators to study organic pollution in rivers and streams. In order to develop a species-level oligochaete biotic index to reflect the River Pollution Index (RPI) in the Taichung Water Basin in Taiwan, we conducted a systematic sampling scheme to collect aquatic oligochaetes from the sediment samples of watercourses in the Taichung Water Basin, Taiwan. We evaluated the relationships between aquatic oligochaetes and the sewage pollution using statistical methods. The distribution of aquatic oligochaetes in relation to environmental variables, such as water quality and sediment characteristics of the regional urban contaminated streams was expressed by Canonical Correspondence Analysis (CCA). We identified 17 species of aquatic oligochaetes (Annelida, Clitellata) including 3 species of Tubificidae, 13 species of Naididae, and 1 species of Enchytraeidae from the watercourses of an urban region in the Taichung Water Basin in Taiwan, during the summer and winter of 2005 and 2006. A positive correlation was found between the total abundance of aquatic oligochaetes and the RPI (r = 0.58, P < 0.05). However, only population density of the most abundant tubificid, Limnodrilus hoffmeisteri, increased with increasing RPI values and a significantly negative correlation was found between the population density of the naidid, Nais communis, and RPI values. The results of CCA indicated that certain naidids, such as Aulophorus furcatus and Allonais gwaliorensis also tolerated extremely polluted environments in upper stream or stony habitats, implying that tubificids should not be the sole representation of simple biotic indices but should also include pollution-tolerant naidids. We found that the community structure of aquatic oligochaetes was influenced by short-term variations in microhabitat rather than according to seasonal factors in our study region. The results proved that aquatic oligochaetes were sensitive enough to provide a supplement for the regional urban pollution assessment applications for biotic indicators at the species-level.  相似文献   

20.
Ecological risk assessment is increasingly being used to make decisions on the acceptability of industrial processes, as well as on the appropriate approach to take with remediation of contaminated sites. In this approach, the risks and costs must first be determined before decisions can be made. In principle, the procedure for undertaking an ecological risk assessment for a site with existing contamination is fairly straight forward. Probability distributions are obtained for the concentration of the contaminant of concern and for the biological and/or structural impacts likely to occur in the affected habitat. The degree of overlap between these distributions determines the risk from the contaminant to the habitat. With water-borne contamination, the level of assessment can vary from a simple comparison with water quality criteria, through site specific literature surveys, to laboratory and field studies depending on the importance of the environment, the concentration and perceived nature of the contaminant,the resources available, and the likely benefit from the process to be developed. However, a number of uncertainties make this process more difficult. These include the lack of a standard methodology, availability of appropriate data and agreed definitions of acceptable risk. Thus several arbitrary or considered decisions need to be made before and during such an assessment. This paper discusses the application of an ecological risk assessment of copper pollution in Macquarie Harbour, Tasmania, using data from long-term monitoring of waters and literature searches on lethal and sub-lethal effects of copper in marine and estuarine environments. This study is part of a much larger program established to determine best methods for the remediation of the Mt. Lyell copper mine site as well as the freshwater and marine habitats downstream. The results of the assessment indicated that there was at present a probability greater than0.9 of the occurrence of anodic stripping voltametry-labile copper water concentrations harmful to 5% of all species. For total dissolved copper the probability was higher than 0.98. The upper value of total dissolved copper in Macquarie Harbour that encompassed 90% of the probable concentrations would need to be reduced by a factor of approximately 30,without the inclusion of any additional application factors, to achieve (sub-lethal) protection for 95%of species. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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