太子河着生藻类群落结构空间分布特征

以辽宁省太子河流域为研究范例,调查了全流域内69个采样点的着生藻类群落和水环境理化特征,并且以着生藻类的群落结构为基础,对太子河流域的水生态系统类型区进行了划分. 结果表明,太子河流域着生藻类群落结构具有明显的空间异质性. CCA(典范对应分析)结果显示,驱动全流域着生藻类群落结构形成的水环境因子为电导率、ρ(TDS)(TDS为总溶解固体)和ρ(TN). 基于着生藻类的群落结构特征,将太子河流域划分为3个着生藻类类型区:第1分区为太子河上游的森林多水区,第2分区为中游低山丘陵森林区,第3分区为下游平原农业区. CCA结果还显示,显著影响第1分区、第2分区及第3分区的着生藻类群落结构的环境因子分别为ρ(NO₃--N)、ρ(TN)及ρ(总溶解固体)和硬度.      

不同植被群落表层土壤中细菌群落多样性

对3种不同植被群落(海桐、雪松、桂花)表层土壤中的pH、w(TOC)、w(TN)和w(TP)进行了测定,采用DGGE(变性梯度凝胶电泳)方法对各植被群落表层土壤细菌的16S rDNA V3~V6可变区扩增片段进行了分析,利用分析得到的图谱数据与表层土壤中的pH、w(TOC)、w(TN)和w(TP)进行了群落-理化因子相关性分析以及CCA(典范对应分析). 结果表明,不同植被群落表层土壤的pH和养分含量不同,其中w(TOC)和w(TN)的差异显著(P<0.05),而pH和w(TP)的差异不显著(P>0.05). DGGE图谱分析结果揭示,不同植被群落表层土壤的细菌群落结构明显不同. 聚类分析显示,海桐和雪松的细菌群落组成和结构最为相似(82%),而它们与桂花样地的相似性(55%)相对较低,桂花样地的Shannon-Wiener指数最高且与其他2个样地差异显著,雪松样地的均匀度指数最高. 相关性分析和CCA结果进一步表明,w(TOC)和w(TN)是表层土壤细菌群落结构和多样性的显著影响因素,并且植被群落可能通过其根系分泌物产生间接影响.      

Modification of evaluation method for auto-assessment and electronic submission by businesses

SUMMARY

This paper describes the evolution of an evaluation method developed initially to assess progress towards sustainable development for various land use activities in Costa Rica. Since that time, the method has been expanded to apply to all types of business activities in any location, and refined so that a numerical score can be provided for each attribute. These scores can then be presented graphically in four categories. The method has since been tested on a variety of businesses and is being refined for electronic submission and display of the results. The benefits of this approach, as well as its shortcomings and some of the problems resolved, are presented.     

REDD+ and forest tenure security: concerns in Nepal’s community forestry

As one of the dominant large-scale mechanisms proposed to combat climate change, biodiversity loss, and rural poverty, REDD+ (Reducing Emissions from Deforestation and Forest Degradation) has added further complexity to the challenging governance of rights and resources in global forests. As REDD+ is commodifying carbon, concerns emerge about how carbon ownership and its rights can be accommodated into the existing framework that governs local forest resource rights. The Nepalese government has formally entered into REDD+ policy preparations, but it lacks clear legal provisions regarding key forest tenure rights such as carbon ownership, benefit sharing, and the political participation of community forest user groups from national to local. As a result, Nepal’s policy process points toward performance-based carbon forestry in a way that may undermine and weaken existing community tenure rights and forest tenure security.

This paper discusses Nepal’s potential impacts of new REDD+ and carbon ownership arrangements on forest tenure security and community-based forest governance. In a threefold methodological approach, the paper presents three scenarios for a REDD+-oriented tenure reform within the existing framework and assesses their concerns through in-depth qualitative interviews with key stakeholders, representatives, and advocates of Nepal’s community forestry system, complemented by a review of government documents and academic literature of REDD+ lessons so far. The analysis identifies critical concerns for forest tenure security, state-community power relationships, and effective local institutions of the commons, and suggests that Nepal’s REDD+ process is taking place at a particularly consequential time for structural changes of the forest governance framework.     

Community sustainability: a holistic approach to measuring the sustainability of rural communities in Scotland

ABSTRACT

Although sustainable development was defined in the Brundtland Report almost 30 years ago, the current usage of the concepts of sustainability and sustainable development remain highly equivocal. In the context of rural communities, multiple interpretations and weak definitions lead to confusion in understanding what comprises a sustainable rural community. Building on existing definitions (e.g. Baker’s, 2006, ‘Ladder of Sustainable Development’), models (principally, The Egan Review’s, 2004, ‘Components of Sustainable Communities’) and findings of this study, a sustainable community is defined and a holistic model of a sustainable place-based rural community is presented. This model, the sustainable community design (SCD) is used as the basis for analysing community sustainability, which is measured using mixed methods and scorecard assessment. Sensitivity of the method is demonstrated with inter- and intra-community variations in sustainability across three diverse Scottish rural communities. Intra-community variations illustrate heterogeneity in community sustainability, explain ambiguity in characterisations of an individual community’s sustainability, and highlight the importance of an interdisciplinary and holistic approach to community development. The SCD framework is presented as a useful tool for meso-level sustainability assessment and to facilitate the sustainable development of rural communities.     

上海海湾国家森林公园1 hm2样地群落结构特征及其动态监测意义

运用生态系统定位监测方法,于2011年在上海市奉贤区海湾国家森林公园内设置面积为100 m×100 m的样地,记录样地内的所有植物种类,定位调查高于1.3m的木本植物,分析其种类组成、区系成分、垂直结构和水平结构.结果表明,1 hm2样地内共记录有维管束植物31科68属73种,其中温带区系成分占总属数的51.8％,热带区系成分占46.4％.高于1.3m的木本植株3 094株,其中常绿树种6种,共1 670株,重要值占48.0％;落叶树种7种,共1 424株,重要值占52.0％.女贞(Ligustrum lucidum)、喜树(Camptotheca acuminata)、椤木石楠(Photinia davidsoniae)、乌桕(Sapium sebiferum)、黄山栾树(Koelreuteria integrifoliola)和香樟(Cinnamomum camphora)的重要值位居前6位,在垂直空间上呈分层结构.在0～50 m尺度范围内,女贞种群均呈集群分布,喜树种群呈均匀-随机-集群分布,椤木石楠和乌桕种群表现为集群-随机-均匀分布,黄山栾树和香樟种群表现为随机-集群-随机分布.从群落结构特征看,样地为以北温带成分、泛热带成分为主的常绿落叶阔叶混交林,表征了该地区自然植被的结构特征.建立长期固定样地可为长三角城市化地区平原地貌上城市森林的发生、发展和演替规律提供长期的数据基础.     

冀东铁矿2种恢复模式植被演替过程中群落结构及生物多样性比较研究

油松（Pinus tabulaeformis）耐低温、干旱和贫瘠,是我国北方温性针叶林中分布最广的森林群落,也是我国北方广大地区最主要的本土造林树种之一,火炬（Rhus typhina Linn.）根萌蘖力强,耐寒、耐旱、耐盐碱,是一种适应周围环境能力极强的外来引入种树种。采用空间代替时间的方法,以冀东铁矿不同年份种植的人工火炬林和人工油松林群落为研究对象,采用样方法进行调查取样,分析了2种恢复模式不同演替阶段群落结构的变化,群落动态,同时采用Pielou均匀度指数、Margalef丰富度指数、Shannon-Wiener多样性指数分析了物种多样性在群落演替过程中的动态变化,在此基础上,对比分析了2种恢复模式在生态效益方面的优劣。主要结果如下：1）短期来看,火炬可以迅速提高植被盖度,增加生物量,但是,长期来看,随着火炬的快速萌集繁殖和林分的郁闭,林下草本急剧减少,形成火炬单优群落,而不能形成稳定的顶级群落。2）短期来看,油松生长缓慢,其生态效益远小于火炬群落,但是油松群落经过11年的演替形成了乔-灌-草3层结构,群落结构逐渐完善。3）演替初期火炬群落优势种以猪毛蒿（Artemisia scoparia）、狗尾草（Setaria viridis）等耐干旱的植物为主,演替后期林下物种迅速减少以至大量消失;油松群落经过11年的恢复,群落草本层植物种数逐渐增大,从一年生先锋植物占优势过渡到以白羊草（Bothriochloa ischaemun）和硬质早熟禾（Poa sphondylodes）为建群种,并出现了黄刺玫（Rosa xanthina）和胡枝子（Lespedeza bicolor）等多年生灌木。4）演替初期Margalef丰富度指数、Pielou均匀度指数和Shannon-Wiener指数表现为：火炬群落﹥油松群落,演替后期则相反,这主要是由群落内种间竞争关系和水热环境的差异造成。4）综合植物群落盖度、物种多样性和群落未来的演替趋势,火炬长期的生态效益远不及油松树种。     

惠州西湖浮游植物磷脂脂肪酸特征研究

对富营养化水体常见浮游植物进行了分离和培养,测定了其磷脂脂肪酸（PLFA）。同时,检测了惠州西湖浮游植物的磷脂脂肪酸;结合惠州西湖浮游植物群落组成数据,分析了浮游植物磷脂脂肪酸特征及其与浮游植物群落结构的关系。结果表明：结合PLFA与细胞丰度和生物量的分析,α-亚麻酸（18：3ω3）的质量浓度与蓝藻（除湖丝藻外）呈正相关;二十碳四烯酸ARA（20：4ω6）和二十二碳六烯酸DHA（22：6ω3）的质量浓度与硅藻呈正相关;二十碳五烯酸EPA（20：5ω3）和16：3ω3的质量浓度与绿藻呈正相关等,其中16：3ω3为绿藻门独有的脂肪酸。这些均与室内实验得到的结果相符合。本研究表明,磷脂脂肪酸可以作为生物标志物来分析浮游植物组成,它将是一种可行的研究浮游植物群落结构的新方法。     

7种阔叶植物群落降噪的临界达标宽度

选取南京市部分主干路道路绿地的7种阔叶植物群落,通过沿道路纵向每间隔5m以及不定距移动测量,结果表明:测量时间段内路缘处噪声的等效连续A声级平均值都超出GB3096-2008中相应规定的限制,其中最高的超出6dB,最低的超出1.3dB;同一阔叶植物群落,随着离开路缘的距离增加,降噪效果更加明显;不同的阔叶植物群落在同一距离处的降噪效果不同,这与植物群落的组成和内部结构特征有密切关系;植物群落的降噪效果与林带宽度并非都呈线性关系;7种阔叶植物群落达到声环境功能区环境噪声限值的临界宽度值集中在5～15m范围内;达到一定宽度的阔叶植物群落可以基本满足城市主干路的降噪要求,在道路绿化中可以广泛应用。     

水稻土甲烷氧化菌对镉胁迫的响应

重金属污染影响土壤微生物群落结构与活性,间接影响土壤碳（如CO2、CH4）的生物地球化学循环和全球气候变化。甲烷氧化菌氧化消耗CH4,降低大气中CH4含量,在缓解由温室气体导致的全球温暖化方面起着重要作用。本研究通过短期土壤培养实验,比较研究了不同强度重金属镉（Cd）胁迫下,水稻土中甲烷氧化菌的多度、群落组成及其氧化CH4潜势的差异。结果表明,添加Cd含量越大,水稻土氧化CH4潜势越弱,甲烷氧化菌pmoA基因拷贝数显著减少;甲烷氧化菌多度与水稻土氧化CH4潜势之间存在显著正相关关系（P〈0.001）。群落组成分析发现,在相对低含量Cd（1 mg.kg-1）条件下,有新的甲烷氧化菌菌属出现,而添加较高含量Cd（10 mg.kg-1）时甲烷氧化菌种类减少。总之,Cd胁迫降低水稻土中甲烷氧化菌多样性及其氧化CH4潜势,可能导致原位CH4消耗减少,从而增加稻田CH4排放。