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1.
高寒草甸植物群落中物种丰富度与生产力的关系研究   总被引:49,自引:2,他引:49       下载免费PDF全文
 以物种组成较为复杂的青藏高原东部地区典革高寒草甸植物群落为背景,从不同的时间和空间尺度水平研究了植物群落中物种丰富度与生产力(地上部生物量)关系的基本模式。结果表明:1)总体而言,高寒草甸植物群落中物种丰富度与生产力的关系呈对数线性增加关系,这实际上是空间和时间尺度放大时在时间和空间尺度的相互作用下高寒草甸植物群落中物种丰富度与生产力关系的一种总体模式;2)随着研究的时间和空间尺度的改变,物种丰富度与生产力的关系会发生一些相应的变化,但空间尺度比时间尺度对物种丰富度与生产力的关系造成的影响更为显著,这可能  相似文献   

2.
紫金山次生林林窗植被和环境的研究   总被引:43,自引:5,他引:43  
研究了紫金山次生林林窗的形成、分布、植被及环境特征 .林窗主要由人为砍伐马尾松形成 ,呈随机分布 .林窗内共出现木本植物 53种 ,频度最高者为枫香 ,频度 1 0 0 % ,其次为刺楸、白栎、黄连木和栓皮栎 .共出现 1 2 83个体 ,其中枫香占 1 8.7% ,黄檀 1 0 .9% ,白栎 8.7% ,刺楸、栓皮栎分别为 5.5%和 5.3% .林窗的种类密度和个体密度分别为 7种和 1 90株·1 0 0m- 2 .方差分析表明 ,枫香、黄檀、白栎和栓皮栎在林窗内的密度分布与随机分布预测值有显著差异 ,反映其分布的非随机性 .林窗内 ,基周 <2cm的个体占 59.0 % ,树龄愈高 ,个体数愈少 ,基周 4cm时 ,个体数下降 70 .5% ,1 0cm时下降 96.2 % .林窗内光照强度、大气温度、大气湿度及土壤元素分布 ,在时序上有近似与旷地的规律性 ,空间上则显现更复杂的格局 .  相似文献   

3.
浙江近海春、夏季蟹类群落结构及其与环境因子的关系   总被引:1,自引:0,他引:1  
根据2015年4月和7月浙江近岸海域单船底拖网调查资料, 分析了春、夏两个季节浙江近岸海域蟹类的种类组成、优势种及资源密度分布, 采用生态多样性指数和丰度/生物量比较曲线(ABC曲线)分析了群落物种多样性及其动态变化, 同时运用典范对应分析(CCA)研究了蟹类群落变化与海洋环境因子的关系。结果表明: 浙江沿岸海域春、夏季共捕获蟹类28种, 隶属于11科19属, 调查海域蟹类主要以暖水性种类占优势; 春季优势种为双斑蟳(Charybdis bimaculata)、三疣梭子蟹(Portunus trituberculatus)和日本蟳(Charybdis japonica), 夏季优势种为三疣梭子蟹和双斑蟳; 两个季节蟹类平均资源密度分别为244.38 和585.60 kg/km2, 中北部海域资源密度高于南部海域; 种类丰富度指数(D)、物种多样性指数(H′)和种类均匀度指数(J′)三种群落多样性指数均不高, 蟹类群落多样性水平处于较低水平; 根据ABC曲线评估干扰对蟹类群落的影响可得: 春、夏季浙江近岸蟹类群落分别处于严重干扰和中等干扰状态; 典范对应分析结果表明: 在进行对应分析的9个环境因子中, 水深为影响研究海域春夏两季蟹类分布的首要环境因子; 盐度(表层和底层)为影响蟹类分布的次要环境因子, 其他环境因子也均在一定程度上影响蟹类群落分布。  相似文献   

4.
根据2015年4月浙江沿岸定点调查资料, 分析了春季调查海域螺类种类组成、优势种、资源生物量和密度、物种多样性以及群落结构与海洋环境因子的关系。结果表明: 浙江沿岸海域春季共捕获螺类27种, 隶属于2目15科21属, 优势种主要有棒锥螺(Turritella bacillum)和褐管蛾螺(Siphonalia spadicea); 螺类平均资源生物量和密度分别为246.64 kg/km2和27.75×103 ind./km2, 总体分布趋势呈现较为明显的斑块分布特征, 但浙北海域资源密度低于浙中南部海域; 种类丰富度指数(D)、物种多样性指数(H′)和种类均匀度指数(J′)的平均值分别为0.36、0.56和0.50, 3种多样性指数均不高, 螺类群落多样性水平处于较低水平, 除物种多样性指数(H′)空间分布特征较为显著以外, 其余2个指数在调查海域整体分布较为均匀; ABC曲线显示浙江沿岸水域春季螺类群落处于中等干扰(或不稳定)状态; 典范对应分析结果表明水深、底层温度和底层溶解氧3个环境因子对研究海域螺类群落的分布起较大的作用。研究旨在探明该海域螺类资源的物种多样性, 丰富我国近海软体动物地理区系的基础资料, 同时也为浙江近海海洋生态和环境保护措施的制定提供参考依据。  相似文献   

5.
科尔沁沙地植物物种丰富度格局及其与环境的关系   总被引:1,自引:0,他引:1  
能量、水分和生境异质性是物种丰富度分布格局的重要因素。本文以特殊环境科尔沁沙地为对象,通过植物区域物种丰富度数据和对应气候数据统计,结合生境异质性分析,对科尔沁沙地物种丰富度格局及其主导因素进行研究。结果显示:(1)科尔沁沙地植物共计有115科1030种,呈现显著的空间异质分布,随着经度的增加物种丰富度呈先下降后上升的趋势,而受纬度影响较小。(2)水热动态假说最适合用于解释科尔沁沙地植物物种丰富度格局。说明水资源可利用性是科尔沁沙地植物物种丰富度的主要影响因素。  相似文献   

6.
通过在高寒矮嵩草(Kobresia humilis)草甸为期4年的刈割(留茬1 cm、3 cm及不刈割)、施肥(尿素7.5 g·m-2·a-1+磷酸二铵1.8 g·m-2·a-1、不施肥)和浇水(20.1 kg·m-2·a-1、不浇水)控制实验, 对该生态系统中功能多样性与物种多样性的变化及其与初级生产力关系进行了研究。结果表明: 刈割和施肥显著影响植物性状和生产力, 而浇水作用微弱。刈割对物种多样性无影响, 但对不同功能多样性指数的影响不同; 施肥降低了物种多样性和以所有性状(除植株高度外)量化的功能多样性; 浇水仅对物种丰富度有微弱影响。各功能多样性的平均值能更好地反映群落物种间的功能差异。功能多样性和物种多样性呈正相关或不相关, 且二者与初级生产力的关系可表现为正相关、负相关和不相关, 说明三者间的关系是性状依赖的, 并受生境资源状况和刈割扰动的影响。植物功能性状对群落初级生产力有更加直接的影响。在考虑生物多样性对生态系统功能的影响时, 应更加注重对植物功能属性变化的研究。  相似文献   

7.
太白红杉群落物种多样性与环境因子的关系   总被引:7,自引:1,他引:7       下载免费PDF全文
定量研究了太白红杉群落物种多样性与环境因子的关系,结果表明:(1)海拔与物种丰富度和种间相遇机率呈极显著的负相关;与Shannon指数、Simpson指数和Pielou指数表现为\"中间高度膨胀\"的规律,即中等海拔高度上多样性高而低海拔和高海拔多样性较低。(2)岩石裸露度与物种丰富度呈显著的负相关。(3)土壤含水量与物种丰富度呈极显著的正相关;与种间相遇机率呈先降后升的趋势。(4)环境因子与物种多样性逐步回归结果是:海拔和岩石裸露度与物种丰富度关系密切,其回归方程为:S=90.62-0.02E-14.14B(r=0.769,P<0.05)。  相似文献   

8.
物种丰富度的大尺度地理格局及其成因是宏观生态学和生物地理学的中心议题之一。本文利用中国陆栖哺乳动物分布数据, 结合高分辨率的气候、地形、植被等环境信息, 探讨了中国陆栖哺乳动物及主要类群的物种丰富度格局及其影响因素。结果显示, 中国陆栖哺乳动物物种丰富度具有显著的纬度梯度格局, 总体上呈现出由低纬度向高纬度逐渐减少的趋势, 并与宏观地形具有良好的对应关系; 其中, 亚热带、热带西部山区的物种丰富度最高, 而东部平原地区、西北干旱区和青藏高原腹地则是丰富度的低值区。各主要类群的物种丰富度格局既有相似性, 又存在差异。最优线性模型的分析结果显示, 由归一化植被指数(NDVI)、生态系统类型数和气温年较差构成的回归模型对哺乳动物物种丰富度格局的解释率最高, 其中NDVI对模型解释率的贡献最大, 这表明中国陆栖哺乳动物物种丰富度的地理分异受多种环境因素的共同影响, 其中植被生产力起主导作用。各主要类群的最优线性模型显示, 影响物种丰富度格局的主要环境因子因类群而异, 这可能反映了各类群进化历史及生理适应的差异。  相似文献   

9.
王思齐  朱章明 《生态学报》2022,42(1):209-219
物种丰富度的大尺度地理格局及其成因是宏观生态学及生物地理学的中心议题之一。蔷薇属(Rosa L.)植物具有很高的经济价值和生态价值,探讨中国蔷薇属植物的丰富度分布格局及其影响因素可为该属植物资源的保护和合理开发利用乃至其系统进化研究提供重要依据。基于蔷薇属植物在中国的15451条分布数据和11种地理、气候等环境因子进行了物种丰富度分析和相关性分析,研究结果显示:(1)蔷薇属植物在中国分布不均匀。在水平方向上,蔷薇属植物于26.19°—34.29°N带内有较高的物种丰富度,之后随着纬度的增加而降低,且随着经度的增加表现为先增加后减少,于99.10°—108.47°E间存在明显的峰值;在垂直方向上,蔷薇属植物的物种丰富度随海拔的增加表现为先增加后减少,956.46—3518.60m范围内的丰富度最高。西南横断山区为蔷薇属物种分布的中心地区,新疆北部及东北长白山周边地区为局部聚集区。(2)蔷薇属物种丰富度与各能量、水分和生境异质性因子均呈正相关关系,与气候稳定性因子呈负相关关系。表明中国蔷薇属植物在水分和热量条件好、气候季节性变化小且生境异质性程度高的地方,有着更高的物种丰富度。(3)蔷薇属...  相似文献   

10.
为探明浙江中南部近岸海域游泳动物的群落结构和多样性, 作者于2016年春季进行了2个航次的底拖网调查, 应用生物多样性指数、冗余分析对游泳动物功能群组成进行了研究。结果表明, 该海域166种游泳动物依据摄食习性可分为6个功能群, 平均丰度百分比最高的为浮游动物/游泳动物食性功能群, 最低的为底栖动物食性功能群; 平均生物量百分比最高的为浮游动物食性功能群, 最低的为碎屑食性功能群。相似性分析结果显示, 该海域游泳动物的功能群结构在不同月份之间差异极显著。4月和5月的功能群多样性均值分别为1.30和1.23, 功能群多样性指数与大个体种类(体质量 > 50 g)的总生物量呈极显著正相关, 功能群多样性与物种多样性呈正相关关系。冗余分析显示该海域游泳动物食性功能群受温度变化影响较大; 底栖动物食性功能群受水深变化影响较大。上述结果表明, 浙江中南部海域游泳动物群落结构相对较稳定。  相似文献   

11.
李珊  刘晓娟  马克平 《广西植物》2023,43(8):1524-1536
生物多样性与生态系统功能的关系(BEF)及其内在机制是当前生物多样性研究领域的热点问题。长期以来,以草地生态系统为主的BEF研究积累了大量研究成果,而基于森林生态系统的相关研究则相对较少。亚热带森林生物多样性与生态系统功能实验研究基地(BEF-China)是目前包含树种最多、涉及多样性水平最高的大型森林控制实验样地。该文总结了基于BEF-China平台的研究进展,特别是生物多样性对生态系统生产力、养分循环以及多营养级相互作用关系等方面的影响,并提出了未来BEF-China的研究应注重高通量测序和遥感等新兴技术的应用,在生物多样性的多维度、生态系统的多种组分与多种功能以及BEF研究的多种尺度等交叉方向上持续开展深入研究。针对BEF-China研究成果的梳理有助于理解驱动亚热带森林生物多样性与生态系统功能关系的内在机理,为生物多样性保护和生态修复提供科学依据。  相似文献   

12.
    
  1. Studies on the effects of human‐driven forest disturbance usually focus on either biodiversity or carbon dynamics but much less is known about ecosystem processes that span different trophic levels. Herbivory is a fundamental ecological process for ecosystem functioning, but it remains poorly quantified in human‐modified tropical rainforests.
  2. Here, we present the results of the largest study to date on the impacts of human disturbances on herbivory. We quantified the incidence (percentage of leaves affected) and severity (the percentage of leaf area lost) of canopy insect herbivory caused by chewers, miners, and gall makers in leaves from 1,076 trees distributed across 20 undisturbed and human‐modified forest plots in the Amazon.
  3. We found that chewers dominated herbivory incidence, yet were not a good predictor of the other forms of herbivory at either the stem or plot level. Chewing severity was higher in both logged and logged‐and‐burned primary forests when compared to undisturbed forests. We found no difference in herbivory severity between undisturbed primary forests and secondary forests. Despite evidence at the stem level, neither plot‐level incidence nor severity of the three forms of herbivory responded to disturbance.
  4. Synthesis. Our large‐scale study of canopy herbivory confirms that chewers dominate the herbivory signal in tropical forests, but that their influence on leaf area lost cannot predict the incidence or severity of other forms. We found only limited evidence suggesting that human disturbance affects the severity of leaf herbivory, with higher values in logged and logged‐and‐burned forests than undisturbed and secondary forests. Additionally, we found no effect of human disturbance on the incidence of leaf herbivory.
  相似文献   

13.
14.
    
Biodiversity, both aboveground and belowground, is negatively affected by global changes such as drought or warming. This loss of biodiversity impacts Earth's ecosystems, as there is a positive relationship between biodiversity and ecosystem functioning (BEF). Even though soils host a large fraction of biodiversity that underlies major ecosystem functions, studies exploring the relationship between soil biodiversity and ecosystem functioning (sBEF) as influenced by global change drivers (GCDs) remain scarce. Here we highlight the need to decipher sBEF relationships under the effect of interactive GCDs that are intimately connected in a changing world. We first state that sBEF relationships depend on the type of function (e.g., C cycling or decomposition) and biodiversity facet (e.g., abundance, species richness, or biomass) considered. Then, we shed light on the impact of single and interactive GCDs on soil biodiversity and sBEF and show that results from scarce studies studying interactive effects range from antagonistic to additive to synergistic when two individual GCDs cooccur. This indicates the need for studies quantitatively accounting for the impacts of interactive GCDs on sBEF relationships. Finally, we provide guidelines for optimized methodological and experimental approaches to study sBEF in a changing world that will provide more valuable information on the real impact of (interactive) GCDs on sBEF. Together, we highlight the need to decipher the sBEF relationship in soils to better understand soil functioning under ongoing global changes, as changes in sBEF are of immediate importance for ecosystem functioning.  相似文献   

15.
    
The capacity of forests to sequester carbon in both above- and belowground compartments is a crucial tool to mitigate rising atmospheric carbon concentrations. Belowground carbon storage in forests is strongly linked to soil microbial communities that are the key drivers of soil heterotrophic respiration, organic matter decomposition and thus nutrient cycling. However, the relationships between tree diversity and soil microbial properties such as biomass and respiration remain unclear with inconsistent findings among studies. It is unknown so far how the spatial configuration and soil depth affect the relationship between tree richness and microbial properties. Here, we studied the spatial distribution of soil microbial properties in the context of a tree diversity experiment by measuring soil microbial biomass and respiration in subtropical forests (BEF-China experiment). We sampled soil cores at two depths at five locations along a spatial transect between the trees in mono- and hetero-specific tree pairs of the native deciduous species Liquidambar formosana and Sapindus saponaria. Our analyses showed decreasing soil microbial biomass and respiration with increasing soil depth and distance from the tree in mono-specific tree pairs. We calculated belowground overyielding of soil microbial biomass and respiration – which is higher microbial biomass or respiration than expected from the monocultures – and analysed the distribution patterns along the transect. We found no general overyielding across all sampling positions and depths. Yet, we encountered a spatial pattern of microbial overyielding with a significant microbial overyielding close to L. formosana trees and microbial underyielding close to S. saponaria trees. We found similar spatial patterns across microbial properties and depths that only differed in the strength of their effects. Our results highlight the importance of small-scale variations of tree–tree interaction effects on soil microbial communities and functions and are calling for better integration of within-plot variability to understand biodiversity–ecosystem functioning relationships.  相似文献   

16.
生物多样性和生态系统功能研究综述   总被引:23,自引:8,他引:23  
李慧蓉 《生态学杂志》2004,23(3):109-114
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。  相似文献   

17.
    

Aim

Theoretical, experimental and observational studies have shown that biodiversity–ecosystem functioning (BEF) relationships are influenced by functional community structure through two mutually non-exclusive mechanisms: (1) the dominance effect (which relates to the traits of the dominant species); and (2) the niche partitioning effect [which relates to functional diversity (FD)]. Although both mechanisms have been studied in plant communities and experiments at small spatial extents, it remains unclear whether evidence from small-extent case studies translates into a generalizable macroecological pattern. Here, we evaluate dominance and niche partitioning effects simultaneously in grassland systems world-wide.

Location

Two thousand nine hundred and forty-one grassland plots globally.

Time period

2000–2014.

Major taxa studied

Vascular plants.

Methods

We obtained plot-based data on functional community structure from the global vegetation plot database “sPlot”, which combines species composition with plant trait data from the “TRY” database. We used data on the community-weighted mean (CWM) and FD for 18 ecologically relevant plant traits. As an indicator of primary productivity, we extracted the satellite-derived normalized difference vegetation index (NDVI) from MODIS. Using generalized additive models and deviation partitioning, we estimated the contributions of trait CWM and FD to the variation in annual maximum NDVI, while controlling for climatic variables and spatial structure.

Results

Grassland communities dominated by relatively tall species with acquisitive traits had higher NDVI values, suggesting the prevalence of dominance effects for BEF relationships. We found no support for niche partitioning for the functional traits analysed, because NDVI remained unaffected by FD. Most of the predictive power of traits was shared by climatic predictors and spatial coordinates. This highlights the importance of community assembly processes for BEF relationships in natural communities.

Main conclusions

Our analysis provides empirical evidence that plant functional community structure and global patterns in primary productivity are linked through the resource economics and size traits of the dominant species. This is an important test of the hypotheses underlying BEF relationships at the global scale.  相似文献   

18.
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。  相似文献   

19.
    
Biodiversity–ecosystem functioning (BEF) studies typically show that species richness enhances community biomass, but the underlying mechanisms remain debated. Here, we combine metrics from BEF research that distinguish the contribution of dominant species (selection effects, SE) from those due to positive interactions such as resource partitioning (complementarity effects, CE) with a functional trait approach in an attempt to reveal the functional characteristics of species that drive community biomass in species mixtures. In a biodiversity experiment with 16 plant species in monocultures, 4‐species and 16‐species mixtures, we used aboveground biomass to determine the relative contributions of CE and SE to biomass production in mixtures in the second, dry year of the experiment. We also measured root traits (specific root length, root length density, root tissue density and the deep root fraction) of each species in monocultures and linked the calculated community weighted mean (CWM) trait values and trait diversity of mixtures to CE and SE. In the second year of the experiment, community biomass, CE and SE increased compared to the first year. The contribution of SE to this positive effect was greater than that of CE. The increased contribution of SE was associated with root traits: SE increased most in communities with high abundance of species with deep, thick and dense roots. In contrast, changes in CE were not related to trait diversity or CWM trait values. Together, these results suggest that increased positive effects of species richness on community biomass in a dry year were mainly driven by increased dominance of deep‐rooting species, supporting the insurance hypothesis of biodiversity. Positive CE indicates that other positive interactions did occur, but we could not find evidence that belowground resource partitioning or facilitation via root trait diversity was important for community productivity in our biodiversity experiment.  相似文献   

20.
1. Many studies indicate that biodiversity in ecosystems affects stability, either by promoting temporal stability of ecosystem attributes or by enhancing ecosystem resistance and resilience to perturbation. The effects on temporal stability are reasonably well understood and documented but effects on resistance and resilience are not. 2. Here, we report results from an aquatic mesocosm experiment in which we manipulated the species richness and composition of aquatic food webs (macrophytes, macro‐herbivores and invertebrate predators), imposed a pulse disturbance (acidification), and monitored the resistance (initial response) and resilience (recovery) of ecosystem productivity and respiration. 3. We found that species‐rich macroinvertebrate communities had higher resilience of whole‐ecosystem respiration, but were not more resistant to perturbations. We also found that resilience and resistance were unaffected by species composition, despite the strong role composition is known to play in determining mean levels of function in these communities. 4. Biodiversity’s effects on resilience were probably mediated through complex pathways affecting phytoplankton and microbial communities (e.g. via changes in nutrient regeneration, grazing or compositional changes) rather than through simpler effects (e.g. insurance effects, enhanced facilitation) although these simpler mechanisms probably played minor roles in enhancing respiration resilience. 5. Current mechanisms for understanding biodiversity’s effects on ecosystem stability have been developed primarily in the context of single‐trophic level communities. These mechanisms may be overly simplistic for understanding the consequences of species richness on ecosystem stability in complex, multi‐trophic food webs where additional factors such as indirect effects and highly variable life‐history traits of species may also be important.  相似文献   

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