基于无人机遥感的天然次生林林窗格局与林下生物多样性关系

林窗作为一种中小尺度干扰在森林群落中广泛存在。林窗可以改善林下光照和水热条件,进而对林下生物多样性产生影响。为进一步研究林窗与林下生物多样性的关系,本研究选取深圳大鹏半岛鹅公村附近面积为1 hm2的阔叶混交次生林为研究对象,将植被调查数据与无人机遥感正射影像相结合,从不同尺度分析了研究地林窗格局与林下生物多样性间的关系。结果表明：1)研究地属典型次生林,群落正处于演替的初、中级阶段,林下层主要由灌木和小乔木组成;2)基于无人机正射影像提取的林窗呈数量多、面积小的空间分布格局,面积在2～15 m²的林窗面积占比达到93.6%,最大林窗面积为20.75m²,平均林窗面积为3.99 m²;3)10 m×10 m和20 m×20 m尺度下,林窗与林下生物多样性间无显著相关关系,5 m×5 m尺度下,最大斑块比例与林下生物多样性指数间产生相关性。综上,在研究区内,随着研究尺度的变小,林窗为林下群落提供异质性生境的能力提高,而在10 m×10 m和20 m×20 m尺度下,林窗难以对林下生物多样性产生影响。     

生物多样性的形成、维持机制及其宏观研究方法

关于生物多样性的形成与维持机制 ,虽有众多假说 ,但均未形成完善的理论体系。不同的学者从不同的角度出发 ,研究了诸多生态因子与生物多样性的关系 ,得出了许多结论、导出了不少争议。本文主要简述了生物因子 (如生产力、生物量、种间关系、土壤微生物 )和非生物因子 (干扰与空间异质性、气候、土壤因子等 )与生物多样性之间的相互作用机理、人类活动对生物多样性的影响 ,以及在生物多样性影响机制研究中所用的 3S技术与数学方法。总之 ,我们应坚持综合作用的观念 ,从不同的时间和空间尺度、在不同的对象层次上 ,全面、深入地研究各类生物和非生物因子与生物多样性之间的相互作用机理 ,才能得出关于生物多样性的形成与维持机制的全面、完善的理论     

野三关红椿天然群落物种多度分布分析

植物多度分布是群落生态学和生物多样性研究的基础。应用生态位优先模型,对数级数模型和对数正态分布模型,对巴东县野三关红椿天然群落乔灌草层的多度分布进行拟合,研究红椿群落的物种多度分布和结构规律,并进行卡方(χ~2)检验,结果表明:3种模型均不能描述草本层物种多度分布,但均可以较好地拟合灌木层和乔木层的物种多度格局;对数正态分布模型既能反映物种的分布宽度,同时其检验对比值表明其拟合效果最佳,可以更加真实可靠地反映野三关红椿群落内在特征及群落结构特点。     

不同尺度生物多样性监测研究进展

生物多样性是人类赖以生存和发展的物质基础和环境保障, 构建合理有效的生物多样性监测指标体系是实现科学保护生物多样性的基础。文中从全球、地区/国家、生态系统3个尺度对国际上生物多样性监测指标体系研究的最新进展进行了回顾, 评述各尺度生物多样性保护监测指标体系的优缺点, 提出了在生态系统尺度上建立森林生物多样性保护监测指标体系的必要性。     

针阔混交林生物量稳定性驱动因子

【目的】阐明生物多样性、胸径结构和地形因子对针阔混交林生物量稳定性的相对影响,明确不同空间尺度下生物量稳定性的主要驱动因素。【方法】在吉林蛟河两个大型固定样地的基础上,通过随机抽取20 m×20 m、40 m×40 m和60 m×60 m样方的方式,定量分析不同空间尺度的影响。利用广义可加模型构建了三类嵌套模型：稳定性～生物多样性+胸径结构(模型1)、稳定性～生物多样性+地形因子(模型2)、稳定性～生物多样性+胸径结构+地形因子(模型3),并与稳定性～生物多样性(模型0)进行比较,通过赤池信息量准则变化量(ΔAIC)、贝叶斯信息量准则变化量(ΔBIC)、调整后的决定系数变化量(ΔR_adj²)和偏差解释率变化量(ΔDE)评价不同解释因子的相对贡献大小。【结果】广义可加模型分析显示,在20 m×20 m、40 m×40 m、60 m×60 m三个尺度上,生物多样性对生物量稳定性的相对贡献率分别为15.18%、12.66%和47.64%,胸径结构的相对贡献率分别为11.30%、72.38%和23.48%,地形因子的相对贡献率分别为73.52%、14...     

物种多样性与生产力研究进展

物种多样性作为生物多样性重要组成之一,与生产力密切相关。文中围绕目前物种多样性与森林生产力存在的4种相关关系展开论述。在大量草地生态系统中物种均匀度和丰富度的增加更有利于促进生产力,而在群落结构和组成起决定作用的自然群落中,生产力不受物种多样性的影响,在人工草地群落中物种多样性甚至会降低生产力,随着森林演替过程物种多样性和生产力呈现非线性关系。样地丰富度、林分结构、环境异质性及尺度被认为是造成不同生态系统物种多样性和生产力相关关系差异的主要因素。然而,目前相关研究主要集中于小尺度、均质生境,忽略了尺度、空间异质性以及优势树种对物种多样性和生产力关系的影响,因此亟待加强大尺度、复杂条件自然群落中物种多样性和生产力之间相关关系的研究。     

圭龙山50年生杉木人工林和天然杉木林群落特征的比较

应用线性模型和Shannon-Wienner多样性指数对圭龙山天然林和50年生的圭龙山人工林两种不同起源的杉木林群落进行比较研究.结果表明,人工林和天然林两个林分均有较高的生物多样性;其人工林林内种——面积关系达到了天然林水平;天然林与人工林在植物种方面存在着较大差异;天然林乔木Ⅰ层和灌木Ⅱ层的多样性指数和均匀度指数高于人工林起源,而草本层和藤本层的多样性指数和均匀度指数则小于人工林起源。     

三峡库区森林生态系统物种多样性定量分析

对三峡库区生物多样性进行定量描述既是现状评价的基础,也是影响预测的基础,更是当前森林经营者将生物多样性纳入规划和决策过程中急需解决的问题。本文根据三峡库区监测样地生物多样性物种调查数据,结合资源调查小班因子与地形环境等因子,分别构建基于区域尺度的三峡库区物种丰度指数、物种多样性指数以及均匀度指数等物种多样性定量指标体系及评价模型,直观地反映三峡库区宏观尺度上的物种的丰度、变化程度或均匀度,揭示森林生态系统的组成与结构的基本差异,较为客观地反映了群落的真实情况,从而为森林生态系统的健康管理提供了量化依据。     

香樟群落生物多样性研究

从保护生物多样性的原则出发,采用生物多样性指数、均匀度、丰富度、优势度等指标,对香樟群落的生物多样性进行测定,分析结果表明：与草本层的多样性指数、均匀度、丰富度、优势度相比较,乔灌层生物多样性指数、均匀度、丰富度均较高,但是优势度低;对香樟群落植物各层的重要值进行计算,结果表明：乔灌层香樟的重要值为59．73357,草本层重要值最高的是铁芒萁,为20．61828。对不同面积的植物多样性指数进行计算,以分析多样性指数对样地面积大小的敏感程度,结果表明：在考虑样地面积对多样性指数影响和精确反映群落物种的多样性方面。Shannon—wiener指数优于NcIntoeh指数。     

不同土地利用方式对蒲江县生物多样性的影响

为进一步掌握四川省蒲江县生物多样性状况，于2020—2021年，对县域内的维管植物、脊椎动物、植被及生态系统开展本底调查与研究，通过自然保护地、重要生态功能区和MaxEnt预测分析识别土地利用格局变化对栖息地质量、生物多样性的影响。结果表明：研究区内生物多样性的显著特点是：物种多样性较差，重点保护野生物种较匮乏，入侵物种占比较高，生态系统组成较简单，多以人工植被为主。蒲江县土地利用格局以耕地、林地和人造地表占绝对优势，维管植物物种数与林地、人造地表呈正相关，与耕地、水域负相关。生物多样性水平受土地利用格局变化影响较大，总体来看，研究区生物多样性极重要区、高度重要区面积分别为4029.72、8973.52 hm²,分别占研究区总面积的6.95%、15.74%。研究结果可为蒲江县快速城镇化的土地利用规划和生物多样性保护管理以及成都市生物多样性保护网络构建、生物多样性调查及监测和生物多样性保护及国家生态园林城市创建和生态文明建设提供参考。     

南峪口铁矿生态影响评价中的植物物种多样性分析

在植被现状调查的基础上,采用物种多样性指数法,对南峪口铁矿生态影响评价的植物物种多样性进行了比较,结果表明：该矿的植被可划分为8个群落类型,反映了矿区不同功能区的植物群落主要类型。根据物种多样性指数的计算结果,不同功能区的植物物种多样性表现出明显差异,按照物种多样性指数大小排序：矿界外评价区＞矿区非开采区＞拟选废石场＞相邻矿区＞工业场地＞炸药库＞铁矿开采区,反映了铁矿开采活动对周边环境干扰程度的差异性。     

Species composition and minimum sampling area of a riparian mixed broadleaved-Korean pine forest in Changbai Mountain Nature Reserve

Riparian areas are unique although often small component of the overall watershed landscape. The structure of riparian forests along Erdaobai River on the north slope of Changbai Mountain were investigated by using field data collected from eight sampling transects perpendicular to the Erdaobai River channel. Two kinds of species-area saturation curves were used to examine the relationship between species number and minimum sampling area. The results showed that riparian gymnosperms accounted for a high proportion of all gymnosperms in the Changbai Mountain Nature Reserve while riparian ferns and angiosperms accounted for a relatively low proportion. The average minimum sampling areas of riparian forest that included 60%, 80%, and 90% of the community species pool were about 85, 185, and 328 m 2 , respectively; while those for nonriparian forest were about 275, 390, and 514 m 2 , correspondingly.     

广东省竹类植物多样性的特点及其应用与保护策略的初步探讨

对广东省竹类植物多样性的四个特征,即珍稀种质资源多样性、竹林类型多样性、生态功能多样性、民族竹文化多样性的特点进行了系统研究,提出了加强广东省竹类植物多样性保护和利用的相关措施。建议将开发利用价值较高的世界性珍稀濒危竹种列入我国保护植物名录,由国家自然科学基金立项资助进行专题研究,给予专项资金在我省建成三大竹类种质资源引种保存和试验研究基地。     

Plant biological diversity in natural secondary forests on Mao’es Mountains

The forest plant biological diversity investigations were conducted in Laoyeling Forest Ecological Experimental Station on Mao’er Mountains in eastern Heilongjiang Province. Sample plots were six different forest communities. Field works were divided into three seasons: spring, summer and autumn in one year. The results showed that forest plant biological diversity varied with seasons as well as growth forms. Herb species diversity values were the highest in the community growth forms. Diversity indices No,H′ andE ₁ were selected out as the best richness, diversity and evenness indices to indicate the biological diversity in forest community. Responsible editor: Chair Ruibai     

Plant biological diversity in natural secondary forests on Mao'er Mountains

IntroductionBioIogicaIdiversityorbiodiversityisthecharacter-isticsofdiverseandlivingentitygrouporcIass.Therearemanydifferenttypesfromgene,cell,individuaI,species,communitytoecosystem.It'sthebasiccharacteristicofIivingsystem(Solbrig1991).Biodi-versityincIudesalIthespeciesandecosystemsofplants,animalsandmicrobes,asweIlastheecologi-calprocessoftheecosystem(McNeelyetal199O).Thisscientifictermconsistsofquantityandfre-quency.Generally,biodiversityisdividedintogeneticbiodi-versity,speciesbiodiv…     

云南绿春县天然次生林和4种人工林树冠层蚂蚁群落多样性

[目的]探讨天然次生林和人工林及人工林树种选择对树冠层蚂蚁群落多样性的影响。[方法]运用树栖蚂蚁陷阱法调查云南省绿春县天然次生林和4种人工林的树冠层蚂蚁群落、植物多样性及植物垂直密度变化。[结果](1)共采集蚂蚁标本17 998头,隶属于6亚科29属68种。(2)树冠层蚂蚁多度:紫胶林-玉米混农林紫胶林桉树林橡胶林天然次生林。(3)树冠层蚂蚁丰富度:紫胶林-玉米混农林紫胶林天然次生林橡胶林桉树林。(4)树冠层蚂蚁ACE估计值:紫胶林-玉米混农林紫胶林天然次生林桉树林橡胶林。(5)树冠层蚂蚁多度和丰富度与枯落物盖度、300 cm处垂直密度和乔木郁闭度呈显著或极显著负相关,而与植物盖度显著正相关;ACE估计值与枯落物盖度、草本植物盖度和乔木郁闭度显著负相关,与175 199.9 cm区段内垂直密度显著正相关。[结论]人工林对蚂蚁多样性保护有一定积极作用,尤其选择乡土树种保护效果更显著,对人工林进行合理的管理有利于保护生物多样性。     

黎蒴栲林等3个乡土阔叶树种群落的多样性及稳定性

在汕头市中小水库库区范围内的水源涵养林中,选择黎蒴栲林、鸭脚木林、山杜英林3个乡土阔叶树种群落,对群落物种多样性、自然更新情况、群落稳定性进行测定分析,结果表明:3个群落的乔木树种多样性表现为山杜英林＞鸭脚木林＞黎蒴栲林,而黎蒴栲林和山杜英林的相对稳定性较高,其物种多样性和稳定性没有出现明显的正相关.3个群落的多样性、稳定性受制于各自建群种的生物学特性及特定的生境条件,并与人为的干扰强度有关.     

小陇山不同灌木林地改造模式林分树种多样性研究

生物多样性研究已经成为生态学研究的热点,而维持物种多样性是目前森林经营研究的一个主要内容。本文运用点抽样方法研究了甘肃小陇山5种不同的灌木林地改造模式的树种多样性。结果表明:带状割灌改造模式林分的树种较全面清理割灌模式丰富,Shannon-Wiener指数与Margalef指数较高,林分的树种多样性较高,林分内各树种分配较为均匀,带状割灌改造更有利于提高林分的树种多样性;在3种全面清理割灌改造模式中,改造日本落叶松模式虽然树种数与其它2种相同,但林分内树种分配均匀性差,集中性高。不同的改造模式对林分树种多样性的影响不同,这对提高和保持改造林分的物种多样性具有一定借鉴意义。     

Managing disturbance regimes to maintain biological diversity in forested ecosystems of the Pacific Northwest

Managing for biodiversity in Pacific Northwest forest ecosystems requires a means to predict the interactive effects of natural, introduced, and altered disturbance regimes. Although disturbances are known to be a determinant of patterns of biological diversity, disturbance and diversity principles have not been consistently applied in management of forest ecosystems in the Pacific Northwest. Here we review disturbance and diversity theory and develop a synthetic conceptual model for use in predicting the effects of disturbances of any origin on biodiversity, focusing on the Pacific Northwest. Disturbance principles have traditionally been applied to understanding patterns of species diversity, but they can also be applied to understanding the broader concept of biodiversity. Our conceptual model integrates these principles, illustrating relationships among mechanisms that limit species diversity and those that enhance it. Diversity-limiting factors are: environmental stress due to high levels of disturbance relative to productivity, and competitive exclusion that can arise where disturbance has been suppressed or managed to favor a particular species’ dominance. Conversely, biological diversity will be enhanced by disturbances that are not too frequent to be stressful, and that create functional heterogeneity (spatial and temporal variation in habitat structure and biological legacies that are vital for post-disturbance reproduction and growth). The three disturbance-related mechanisms that determine diversity operate over local to landscape spatial scales and ecological time scales and thus can be readily influenced by management. By comprehensively evaluating existing disturbance regimes and how they are influencing these factors, managers can help maintain or restore the ecological foundation for biodiversity. We describe management approaches to improve this foundation focusing on forests managed for multiple goals in the Pacific Northwest, where there is considerable potential for and interest in maintaining and enhancing biodiversity.     

The effect of landscape context on the biological control of <Emphasis Type="Italic">Sitobion avenae</Emphasis>: temporal partitioning response of natural enemy guilds

Landscape contexts with high complexity may promote diversity of natural enemies, although the effect on biocontrol remains under discussion. Although biocontrol of Sitobion avenae is a well-studied system, little is known about the temporal effect of landscape context on the natural enemy assemblages. In a previous study, we showed a positive effect of predators in the decline of aphids; however, this effect had a temporal pattern responding to different landscape contexts. We study here two contrasting agricultural contexts, high landscape complexity with low intensification and low complexity with high intensification. Abundance and diversity of parasitoids was examined via a molecular approach, using a combination of diagnostic multiplex and singleplex PCR assays to test field-collected samples of S. avenae with genus- and species-specific parasitoid primer pairs. Temporal population dynamics were analyzed and differences related to these two contexts were observed. Parasitism rates were greater in the mid-sampling dates in high intensification simple landscapes, which were not observed for the low intensification complex landscapes. According to our results, we suggest that the greater landscape complexity in combination with a low agricultural intensification increase negative interactions for parasitoid population built-up; however, early predation by coccinellids was able to control the aphid populations. In contrast, under a simple landscape context with a high agricultural intensification, our results suggest an important role of parasitism with a complementary effect of late predation. We highlight the importance of different natural enemy guilds and their temporal dynamics under contrasting agricultural settings to further understand the relationship between functional diversity and biological control.