The significance of waterfowl grazing in the primary vegetation succession on embanked sandflats

In the annual stage of a primary plant succession on desalinating sandflats of the Lauwerszeepolder, N Netherlands, grazing by waterfowl is a dominant factor, as is illustrated by exclosures. It is concluded from population dynamical data, that both the removal of biomass and the predation of seeds sustain the annual species and retard succession to wards the next stage of a perennial grassland by several years. Yearly mowing in September slightly enhances succession by selectively affecting the dominant annual Salicornia species. The recurrence of high salinities in the upper soil layer of bare, c.q. grazed surfaces is expected to limit the invasion of grass species and other perennials.Nomenclature of plant taxa follows Heukels/van der Meijden (1983), Flora van Nederland, 20th ed. Wolters-Noordhoff, Groningen.This article would not have been written without the contributions of many students and colleagues, equally aware of the rare opportunity we had to study a genuine primary succession. I wish to thank them all. The help in the moving experiment of J. Franke, S. Nijdam, the late M. Robertus, H. Vrieling and J. D. D. Hofman is gratefully acknowledged. Thanks are due to the State Authority of the IJssellake Polders, for permitting access to and use of the experimental areas.     

Establishing the South Australian Macrobenthic Traits (SAMT) database: A trait classification for functional assessments

Trait‐based approaches are increasingly used as a proxy for understanding the relationship between biodiversity and ecosystem functioning. Macrobenthic fauna are considered one of the major providers of ecosystem functions in marine soft sediments; however, several gaps persist in the knowledge of their trait classification, limiting the potential use of functional assessments. While trait databases are available for the well‐studied North Atlantic benthic fauna, no such trait classification system exists for Australia. Here, we present the South Australian Macrobenthic Traits (SAMT) database, the first comprehensive assessment of macrobenthic fauna traits in temperate Australian waters. The SAMT database includes 13 traits and 54 trait‐modalities (e.g., life history, morphology, physiology, and behavior), and is based on records of macrobenthic fauna from South Australia. We provide trait information for more than 250 macrobenthic taxa, including outcomes from a fuzzy coding procedure, as well as an R package for using and analyzing the SAMT database. The establishment of the SAMT constitutes the foundation for a comprehensive macrobenthic trait database for the wider southern Australian region that could facilitate future research on functional perspectives, such as assessments of functional diversity and changes to ecosystem functioning.     

Effects of Copper Contamination on RumexK-1 Response

The effects of Cu contamination on RumexK-1 were studied using a pot trial. The results showed that the dry weight of leaves and roots did not change significantly under Cu stress when compared with CK (0 mg kg^?1 Cu). Additionally, there was no difference in the amounts of chlorophylla, chlorophyllb, chlorophyll (a+b), and the chlorophylla/b ratio between the CK and Cu treatments. The Cu accumulated in leaves and roots, particularly in the roots, with more Cu accumulating in the plants at higher Cu concentrations in the soil. The proline and soluble protein contents in the leaves were more sensitive to Cu contamination than in the roots. Finally, Cu contamination significantly inhibited the acid phosphatase, alkaline phosphatase, and peroxidase activities in the leaves. These results indicate that RumexK-1 is a plant that can accumulate Cu, exhibits some different metabolic mechanisms under Cu stress, and may be suitable for the phytoremediation of Cu contaminated soils.     

野生动物的价值与生态服务功能

野生动物是生态系统中活跃的、引入注目的组成部分。野生动物作为生物多样性的一部分,具有内禀价值和利用价值。同时,野生动物的价值也取决于人们的视角,即人们自身的利益。野生动物服务功能的实现离不开自然生态系统。在人类文明的早期,人类利用野生动物果腹御寒。那时,人们利用的是野生动物的直接价值。现代,野生动物的直接价值下降,野生动物的间接价值,如生态价值、文化价值却在上升。野生动物能够提供巨大的生态系统服务功能。1996年,美国人与野生动物直接有关的消费达1012亿美元,相当于中国国民总产值的10％以上。在东部和南部非洲,野生动物观光也是一项重要的产业。这种生态服务功能带动了第三产业的发展,直接推动了地区性的国民经济发展。有效的野生动物资源管理离不开控制野生动物的数量。以野生动物产业的收入养野生动物是美国野生动物保护的角色。中国的野生动物正处于利用过度期。中国野生动物提供的服务功能比美国的野生动物少得多。近年来,开展了野生动物战利品狩猎。中国对野生动物战利品狩猎的种类制定了限额,实行了严格的管理措施,以保证战利品狩猎不会影响种群的增长。事实证明有限额的战利品狩猎能促进野生动物的饿保护。当前,我国的野生动物管理应将保护野生动物的栖息生境和扩增濒危野生动物的种群为主要目的,我国的多数野生动物一旦种群数量恢复,脱离濒危状态,那些野生动物的生态系统服务功能将会对我国的国民经济产生巨大的推动作用。     

土壤微食物网结构与生态功能

土壤微食物网是碎屑食物网中与土壤生态过程密切相关的一部分,通过取食资源基质直接或间接地参与养分循环过程,影响陆地生态系统功能.本文从土壤微食物网的组成、结构和生态功能等方面综述了近年来土壤微食物网的研究进展.通过对土壤微食物网的能量通道及营养级联效应的介绍,阐述了土壤微食物网在碳(C)、氮(N)转化、凋落物分解和植物生长等方面的重要作用.针对目前的研究现状,提出未来土壤生态学研究应与高通量测序及稳定同位素技术相结合;通过构建模型进一步加强对土壤食物网结构和功能的研究,从而深入揭示地下生态过程及其对地上植物生长的反馈作用机理.     

基于生态系统服务功能和生态敏感性的生态空间划定研究——以南宁市为例

生态空间管制是我国国土空间管制的重要内容。针对目前国内对生态空间认知有差异,对其划定技术方法还处于探索阶段的情况下,以生态系统服务功能和生态敏感性技术评价方法为手段,以广西壮族自治区南宁市为研究对象,开展了基于生态系统服务功能重要性和生态敏感性的生态空间划定方法的探索研究。结果表明:(1)研究区域内主导的生态系统服务功能主要为生物多样性维护功能和水土保持功能,其次为水源涵养功能。生态系统综合服务功能重要性类型以一般重要为主,约占研究区总面积的42.32%。(2)研究区生态敏感性以水土流失敏感性为主,其次为石漠化敏感类型。生态环境综合敏感类型以敏感为主,约占总面积的85.44%。(3)研究区内初步划定生态空间总面积约9325.27 km~2,占研究区总面积的42.19%,占研究区内生态用地面积的76.59%。土地利用类型以林地为主,约占生态空间面积的83.65%。划定的生态空间范围涵盖了绝大部分生态用地。本研究在一定程度上丰富了生态空间的内涵,可为进一步理解和划定生态空间提供参考与借鉴。     

生态系统多功能性的测度方法

生物多样性与生态系统多功能性(biodiversity and ecosystem multifunctionality, BEMF)之间的关系是目前生态学研究的一个热点, 其中, 生态系统多功能性(EMF)的测度方法是研究该问题的技术关键。由于缺乏统一的认识, 目前存在多个多功能性的测度方法, 这使人们对生物多样性与生态系统多功能性之间关系的理解复杂化。本文介绍了国际上常用的单功能法、功能-物种替代法、平均值法、单阈值法、多阈值法、直系同源基因法和多元模型法的原理及其特点, 并对其中较难理解的多阈值法进行了举例说明, 希望能对理解EMF的测度方法有所帮助。本文按不同的EMF测度方法对已发表的有关文章进行了归类, 以期帮助读者更好地选择EMF的测度方法。由于缺乏相对统一的、代表各个层次的生态系统功能的测度方法, 导致不同的研究结果难以相互比较, 严重限制了生物多样性与生态系统多功能性研究的发展; 所以, 研发新的、具有普遍适用性的EMF测度方法已成为当务之急。     

中国生态区划研究进展:从格局、功能到服务

在总结国内外生态区域研究的基础上,系统梳理了中国现有的生态区划方案,总结出生态特征和类型区划、生态地理和格局区划、生态功能和服务区划三大类,分别对每个区划的指标、技术、方案、特点进行了归纳,并提出了各自存在的问题。现有研究缺少面向服务供需的生态系统区划,生态制图和更新的标准化技术也存在不足。为此,提出明确不同生态区划的科学或管理目标、强调人类需求对于生态系统服务的影响、重视全球气候变化对生态系统的现实作用和未来影响、加强现代制图技术在生态区划的作用、整合现有多原则和多目标的生态分区方案等五个方面的建议。     

污水污泥土地投放重金属的环境效应研究进展

本文综述了污水污泥土地投放中重金属的环境效应研究方面的进展,重点就污水污泥土地投放中对植物生长的影响、对土壤微生物、土壤酶及昆虫生长的影响、重金属向地下水中的迁移情况、重金属在土壤中的生物活性变化及其影响因素、污水污泥土地投放后重金属的长期变化及土壤修复剂对重金属毒性的控制等方面的研究进展进行综述。     

黄土高原区域生态综合研究:机理深化与方法拓展

黄土高原是我国生态环境最为脆弱的地区之一,同时也是我国大规模生态恢复的重点区域。经过数十年的治理,黄土高原生态环境得到显著改善,但一系列新的环境问题也随之出现,使得该区域大规模生态修复与治理的可持续发展成为当前的研究热点。为了对黄土高原生态系统演变规律和维持机制进行综合分析与探索,根据"十三五"国家重点研发计划《典型脆弱生态修复与保护研究专项指南》的要求,中国科学院生态环境研究中心牵头共10家单位联合申报了"黄土高原区域生态系统演变规律和维持机制研究"项目,通过了专业机构组织的评审,获准立项。对该项目的立项背景、总体目标、主要内容、研究方案等进行介绍。该项目的开展将对黄土高原生态修复的适宜性和可持续发展提供重要政策与决策支持。     

大型真菌对重金属的生物富集作用及生态修复

大型真菌是一类重要的环境生物资源,对人类的生存具有重要作用.与绿色植物相比,大型真菌能够积累高浓度的Pb、Cd和Hg等重金属.本文论述了大型真菌对重金属的生物富集作用以及利用大型真菌进行重金属生态修复的优势,指出大型真菌种类、生态类型、富集重金属的生物学特性及其遗传潜能、大型真菌菌丝体和子实体的形态、部位、寿命以及结实间隔和环境因子等是影响大型真菌吸收和积累重金属的主要因素.筛选富集重金属功能强大、易于人工栽培、环境适应性强、便于后处理的大型真菌是今后研究的重要方向.     

Influence of macrofaunal assemblages and environmental heterogeneity on microphytobenthic production in experimental systems

Despite the complexity of natural systems, heterogeneity caused by the fragmentation of habitats has seldom been considered when investigating ecosystem processes. Empirical approaches that have included the influence of heterogeneity tend to be biased towards terrestrial habitats; yet marine systems offer opportunities by virtue of their relative ease of manipulation, rapid response times and the well-understood effects of macrofauna on sediment processes. Here, the influence of heterogeneity on microphytobenthic production in synthetic estuarine assemblages is examined. Heterogeneity was created by enriching patches of sediment with detrital algae (Enteromorpha intestinalis) to provide a source of allochthonous organic matter. A gradient of species density for four numerically dominant intertidal macrofauna (Hediste diversicolor, Hydrobia ulvae, Corophium volutator, Macoma balthica) was constructed, and microphytobenthic biomass at the sediment surface was measured. Statistical analysis using generalized least squares regression indicated that heterogeneity within our system was a significant driving factor that interacted with macrofaunal density and species identity. Microphytobenthic biomass was highest in enriched patches, suggesting that nutrients were obtained locally from the sediment-water interface and not from the water column. Our findings demonstrate that organic enrichment can cause the development of heterogeneity which influences infaunal bioturbation and consequent nutrient generation, a driver of microphytobenthic production.     

Heavy Metal Contamination in the Brownfield Soils of Cleveland

The results esults of a survey of heavy metal contamination at Cleveland area brownfields and public spaces are presented. Soils were analyzed using a 24?h, 1N HCl extraction procedure. The study was conducted to seek brownfield soils that manifest properties of “old” sequestered contamination and to develop a better understanding of the nature and extent of heavy metal burdens at brownfield sites in the Greater Cleveland area. The results indicated that Cleveland brownfields commonly yield soil burdens well above remediation triggers for residential soils and often yield values above industrial remediation triggers. It was also discovered that public areas in the vicinity of brownfields commonly have heavy metal contamination significantly above background levels and occasionally above residential remediation triggers. These results indicate that brownfields redevelopment initiatives should proceed with caution. The appropriate remediation goals or restrictions must be imposed to control urban exposure to heavy metal contamination.     

重金属污染土壤植物修复中的微生物功能研究进展

综述了国内外在重金属污染土壤植物-微生物联合修复领域的研究报道,总结了近5年的研究实例。植物-微生物联合修复体系具有生物固定与生物去除土壤重金属的两种功能,根际微生物可以菌根、内生菌等方式与根系形成联合体,通过增强植物抗性和优化根际环境,促进根系发展,增强植物吸收和向上转运重金属的能力。建立植物-微生物联合修复体系,可充分发挥植物与微生物作用功能的优势,提高污染土壤的修复效率。增强植物修复体系中微生物功能的重点是深入研究根际微生物、根系和介质载体三者之间复合功能,结合污染土壤类型与植物群落配置的特点筛选扩繁高效菌种与菌群。     

Sources of organic carbon in mangrove sediments: variability and possible ecological implications

Mangrove sediments from three different mangrove ecosystems (Coringa Wildlife Sanctuary in the Godavari Delta, Andhra Pradesh, India, and Galle and Pambala, south-west Sri Lanka) were analysed for their organic carbon content, elemental ratios (C:N) and carbon stable isotope composition. Organic carbon content (0.6 – 31.7% dry weight), C/N ratios (7.0 – 27.3) and ¹³C (between –29.4 and –20.6) showed a wide range of values. Lower stocks of organic carbon coincided with low C/N (atom) ratios and less negative ¹³C values, indicating import of marine or estuarine particulate suspended matter. High organic carbon stocks coincided with high C/N ratios and ¹³C values close, but not equal, to those of the mangrove vegetation. The variations observed in this study and published literature data could be adequately described by a simple two-end mixing model, whereby marine/estuarine suspended matter and mangrove litter were taken as end members. Thus, while in some mangrove ecosystems or vegetation zones, organic carbon stocks can be very high and are almost entirely of mangrove origin, there also appear to be cases in which deposited estuarine or marine suspended matter is the dominant source of organic carbon and nitrogen in mangrove sediments. This situation is remarkably similar to that observed in temperate salt marsh ecosystems where the importance of local vascular plant production to the sediment organic carbon pool is equally variable. The observed high variability in organic matter origin is thought to have a major impact on the overall carbon dynamics in intertidal mangrove ecosystems.     

生物多样性和生态系统功能研究综述

生物多样性和生态系统功能之间关系 ,是生态学和环境科学的热门话题。围绕这一主题 ,文章系统回顾了近 2 0年来的研究历史及学术界的不同观点 ,全面展示了目前在理论和实验领域的主要工作结果和研究进展 ,并对今后的发展趋势和面临的挑战作了展望。理论和实验研究都表明 ,生物多样性趋于与生态系统功能 (稳定性 )呈正相关性 ,但是多样性并非是这种关系的直接驱动力。生态系统功能 (稳定性 )潜在地依赖于物种之间相互作用的强度 ,物种的功能反应特性以及生态系统的类型和尺度等。在生物多样性和生态系统功能的研究中 ,重要的不只是结论 ,还应包括其中所隐含的机制。     

湘南某矿区蔬菜中Pb、Cd污染状况及健康风险评估

通过采集湘南某矿区周边农田中种植的蔬菜和对应耕作层土壤样品,探究了农田蔬菜Pb、Cd的污染状况,蔬菜和土壤重金属含量之间的相关性,蔬菜中重金属对人体的健康风险。结果表明:(1)污染区土壤重金属污染非常严重,叶菜类蔬菜重金属超出了食品卫生标准限值,但是果菜类蔬菜中重金属没有超出食品卫生标准限值。(2)不同蔬菜不同器官所含Pb、Cd有明显差异;不同种类蔬菜Pb、Cd含量不同,一般是叶菜类果菜类;同种蔬菜不同部位重金属含量的顺序也不同,一般为根茎叶果,或根叶茎果。(3)二类蔬菜中重金属Pb、Cd的富集系数顺序为叶菜类果菜类。(4)蔬菜中Pb、Cd含量与土壤中相对应元素含量均无显著相关性。(5)就农产品安全性而言,果菜类蔬菜比叶菜类蔬菜更适合在此矿区栽培。     

基于生态系统演变机理的生态系统脆弱性、适应性与突变理论

随着气候变化影响广度与深度的增加,生态系统脆弱性、适应性与突变理论逐渐被广泛应用到生态学研究领域中,探讨和评估各类生态系统对气候变化的敏感性、脆弱性和适应性,可谋求更好的方式来应对气候变化对区域生态系统带来的深远影响,服务于国家生态系统可持续管理及生态安全建设.虽然相关研究已获取许多进展,区分了气候敏感区和某些生态系统...     

成都平原北部水稻土重金属含量状况及其潜在生态风险评价

为了解成都平原水稻土重金属含量状况和潜在的生态风险,选取成都平原北部水稻土典型区域为研究对象,采集了158个表层土壤样品,分析了土壤中pH值和Cd、Cu、As、Hg、Pb、Cr、Ni 7种重金属元素含量,以20世纪80年代测定的成都平原土壤重金属元素背景值为评价标准,采用Hakanson潜在生态危害指数法对研究区域的重金属潜在生态风险进行了评价。结果表明:研究区域水稻土Cd、Hg、Ni、Cu、Pb、Cr和As平均含量分别为0.709、0.187、32.08、34.12、31.52、82.13 mg/kg和7.25 mg/kg;Cd、Ni、Cu和Hg 4种重金属超过《土壤环境质量标准》(GB15618-1995) Ⅱ级标准值样本比例分别为87.34%、8.23%、3.80%和3.80%,Cd含量超标严重。7种重金属元素变异系数幅度为18.35%-49.03%,由大到小依次为Cd、Hg、Cu、As、Ni、Cr、Pb。75.32%的样本达到中度或较强重金属潜在生态风险,区域整体表现为中度潜在生态风险(RI平均值为198.65),Cd和Hg为高生态风险元素,对潜在生态风险贡献率分别为62.27%和20.78%,As、Pb、Cu、Ni、Cr为低生态风险元素;风险概率图显示城区周边和绵远河沿线的潜在生态风险等级较高。因此,成都平原水稻土农业生产中应采取一定的措施防控农产品Cd和Hg污染。     

汕头湾表层沉积物重金属污染与潜在生态风险评价

汕头湾作为华南地区重要的出海门户,汕头市主要的旅游区和水产养殖基地,其环境污染问题已成为制约当地经济发展的重要因素,为此2002年在此开展了重大科技术兴海项目,以海洋沉积物质量标准、单因子污染指数和潜在生态风险评价体系对汕头湾表层沉积物重金属污染现状和潜在生态风险进行了评价。结果表明:汕头湾表层沉积物中Cd,Cu,Pb,Zn的平均含量超过海沉积物质量标准(Ⅰ类);以单因子污染指数评价,Cd达到很强污染等级,Zn为强污染,Cu,Ni,Pb为中等污染;以单元素生态系数(E_rⁱ)评价,只有Cd的潜在生态风险达到很强等级,其它元素则只属于轻微潜在风险范畴;以多元素潜在生态风险指数(RI)评价,汕头湾的潜在生态风险水平处于中等强度;重金属含量分布特征与重金属污染及潜在生态风险的空间差异性一致,表现为由上游至下游呈波状递减趋势,其中以牛田洋和汕头港上游最为严重;这一污染特征主要是由集水区域内的产业结构特点、河流入海口及排污口的分布以及汕头湾的地理和水文特性所决定的。