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1.
In the past, insect species richness was high in Central European seminatural grasslands, which were characterized by low‐intensity land use. Currently, however, the hay in most of these grasslands is mechanically harvested, which negatively impacts insect biodiversity. One way to reduce this negative effect is to leave unmown patches as refuges. In the current research we evaluated the short‐term effects of leaving an unmown patch on the taxonomic and functional diversity of the Orthoptera assemblage in a meadow. We found that orthopteran species richness and abundance were significantly reduced by mowing, whether or not a patch was left uncut. In contrast, functional evenness, indicating distribution of species abundances in a niche space, was reduced by mowing only if the plot lacked an uncut refuge. Functional richness, indicating the amount of niche space occupied by species, was elevated if the plot had an uncut refuge. Larger species were negatively affected by mowing, while habitat specialists, mobile species and soil‐ovipositing species benefitted from it. We infer that the presence of an uncut patch increased the diversity of habitats available to orthopterans and maintained even distribution of species among niche space. In summary, leaving an unmown refuge in grasslands could increase the functional diversity of orthopterans, even if it does not preserve taxonomic diversity. 相似文献
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高寒草甸具有重要的生态服务功能,然而固有脆弱性使其极易遭受气候变化和人为干扰等多重因素的影响。作为滇西北旅游资源中重要的组分之一,高寒草甸吸引了大批游客前往开展徒步旅行活动,但伴随着的践踏干扰作用会不可避免地对高寒草甸生态系统带来负面影响。然而,目前关注践踏干扰对滇西北高寒草甸植被的影响,特别是植被功能性状和功能多样性如何发生变化方面的研究还十分欠缺。以云南省香格里拉市碧塔海自然保护区内的典型高寒草甸生态系统为研究对象,采用实验践踏的方式(一共5种不同强度的践踏处理)来模拟旅游活动对草甸植被的干扰作用,并以草甸植被的茎叶性状特征为切入点,重点探讨践踏干扰对茎叶性状的平均大小和变异程度的影响,以及物种丰富度(以物种形态分类为基础)和功能丰富度(以功能性状为基础)之间的关系。研究结果显示,随着践踏强度的增加,植株高度和叶片大小的平均值,而不是茎叶性状的变异程度,出现明显下降趋势。此外,物种丰富度和功能丰富度均随践踏强度的增强而减小,且两者之间呈现显著正相关关系。然而,较之轻度践踏实验组,重度践踏实验组中的功能均匀度和功能分离度水平均有所增加,表明践踏干扰可能会在短期内打破优势种对资源的绝对占有格局和减少物种间的生态位重叠程度。尽管高寒草甸对人类践踏活动有一定的承受能力,但气候变化和人为干扰等多重因素势必会改变和影响高寒草甸群落的结构和功能可持续性,这也对高寒草甸的保护与管理工作提出了更加紧迫的要求。 相似文献
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放牧和刈割对内蒙古典型草原大型土壤动物的影响 总被引：1，自引：0，他引：1
采用连续3年全季节放牧、3种季节性轮牧、秋季刈割和不利用对照6种处理, 研究了内蒙古典型草原大型土壤动物群落特征.调查在春、夏和秋3个季节进行,共捕获大型土壤动物597只,隶属于2门4纲11目,49个类群.结果表明: 全季节放牧导致土壤动物的个体密度、生物量和多样性降低;而刈割的影响相对较轻,土壤动物的个体密度、生物量和多样性甚至有提高趋势.3种季节性轮牧处理中,夏季和秋季放牧2次处理对土壤动物群落个体密度、生物量和多样性等指标的负面影响较轻.刈割管理对退化典型草原大型土壤动物群落的恢复较为有利;夏季和秋季放牧2次处理对大型土壤动物群落的负面影响较轻,是较理想的草地可持续管理措施. 相似文献
4.
阔叶红松林是东北森林的典型代表,由于受到历史采伐干扰的影响,导致生态系统功能严重退化,威胁东北地区生态安全。生物多样性是生态系统功能形成和维持的重要基础,阐明采伐前后生物多样性的变化对于评估采伐干扰的影响、理解森林恢复过程具有重要意义,能够为森林生态修复与重建提供理论支持。谱系多样性和功能多样性是生物多样性的两个重要维度,然而传统的研究仍停留在物种数量层面,难以全面反映采伐干扰的影响。以吉林蛟河阔叶红松林采伐样地为对象,依托连续四次的样地清查数据,同时结合植物的系统发育和功能性状信息,探讨了不同强度采伐干扰对谱系多样性和功能多样性的影响,具体采伐设置包括：未采伐（对照）,采伐15%胸高断面积（轻度采伐）,采伐30%胸高断面积（中度采伐）以及采伐50%胸高断面积（重度采伐）。结果显示：（1）中、高强度的采伐干扰显著降低了森林谱系多样性和功能多样性,并且高强度干扰条件下森林多样性的恢复要更加困难;（2）采伐还影响着群落功能性状组成,随着采伐强度的增加,群落木质密度加权平均值上升而最大树高下降;（3）相较于采伐强度和采伐木断面积,保留木断面积与生物多样性的联系更加紧密,表明采伐后森林所达到的密度状态是影响生物多样性恢复的关键,当保留木断面积在18m2/hm2附近时,其与谱系多样性的关系出现显著拐点,应在阔叶红松林经营管理过程中受到更多重视。综上所述,谱系多样性和功能多样性为评价采伐的影响提供了新的视角,有助于更加全面地反映采伐干扰对生物多样性的影响,为阔叶红松林生态修复与多样性保护提供科学参照。 相似文献
5.
James R. Lawson Kirstie A. Fryirs Tanja Lenz Michelle R. Leishman 《Freshwater Biology》2015,60(11):2208-2225
- Riparian ecosystems are biophysically complex and highly diverse taxonomically, structurally and functionally. While many environmental factors determine the structure and function of riparian vegetation communities, hydrology is thought to be the ‘master variable’. Flooding and variability in water availability are known to be key drivers of taxonomic diversity, but their influence on the functional trait diversity of riparian vegetation communities remains largely unexplored.
- We collected data on species abundance, quantitative plant functional traits and hydrology from 15 sites distributed across south‐eastern Australia to address the following questions: (a) Is functional trait diversity related to the frequency and magnitude of flooding disturbance? (b) Is functional trait diversity related to variability in seasonal water availability within the riparian zone?
- We confirm that metrics describing both flooding disturbance and patterns of water availability exhibit strong relationships with functional trait diversity in riparian vegetation communities of south‐eastern Australia. Our key finding is that functional trait diversity in these systems tends to be positively associated with variability in hydrological conditions and the intensity of rare, high‐magnitude flooding events, rather than average patterns of flow.
- Our study highlights the importance of extreme flooding events and temporal patterns of water availability as determinants of diversity in riparian vegetation communities. These relationships may have significant consequences for plant communities experiencing alterations to hydrology caused by anthropogenic flow modification and the changing climate.
6.
Xiao‐Bo Wang Chih‐Ming Hsu Jos C. B. Dubeux Cheryl Mackowiak Ann Blount Xing‐Guo Han Hui‐Ling Liao 《Ecology and evolution》2019,9(22):12676-12687
There is a growing awareness of the importance of soil microorganisms in agricultural management practices. Currently, much less is known about whether different crop cultivar has an effect on the taxonomic structure and diversity, and specific functions of soil bacterial communities. Here, we examined the changes of the diversity and composition and enzyme‐encoding nitrogenase genes in a long‐term field experiment with seven different rhizoma peanut cultivars in southeastern USA, coupling high‐throughput 16S rRNA gene sequencing and the sequence‐based function prediction with Tax4Fun. Of the 32 phyla detected (Proteobacteria class), 13 were dominant: Acidobacteria, Alphaproteobacteria, Actinobacteria, Betaproteobacteria, Bacteroidetes, Verrucomicrobia, Gammaproteobacteria, Deltaproteobacteria, Gemmatimonadetes, Firmicutes, Nitrospirae, Chloroflexi, and Planctomycetes (relative abundance >1%). We found no evidence that the diversity and composition of bacterial communities were significantly different among different cultivars, but the abundance of some dominant bacterial groups that have N‐fixation potentials (at broad or fine taxonomic level) and predicted abundances of some enzyme‐encoding nitrogenase genes showed significant across‐cultivar differences. The nitrogenase genes were notably abundant in Florigraze and Latitude soils while remarkably lower in Arbook and UF_TITO soils when compared with other cultivars, indicating different nitrogen fixation potentials among different cultivars. The findings also suggest that the abundance of certain bacterial taxa and the specific function bacteria perform in ecosystems can have an inherent association. Our study is helpful to understand how microbiological responses and feedback to different plant genotypes through the variation in structure and function of their communities in the rhizosphere. 相似文献
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F. Baptist H. Secher‐Fromell F. Viard‐Cretat I. Aranjuelo J.‐C. Clement A. Creme M. Desclos P. Laine S. Nogues S. Lavorel 《Plant biology (Stuttgart, Germany)》2013,15(2):395-404
Cessation of traditional management threatens semi‐natural grassland diversity through the colonisation or increase of competitive species adapted to nutrient‐poor conditions. Regular mowing is one practice that controls their abundance. This study evaluated the ecophysiological mechanisms limiting short‐ and long‐term recovery after mowing for Festuca paniculata, a competitive grass that takes over subalpine grasslands in the Alps following cessation of mowing. We quantified temporal variations in carbon (C) and nitrogen (N) content, starch, fructan and total soluble sugars in leaves, stem bases and roots of F. paniculata during one growth cycle in mown and unmown fields and related them to the dynamics of soil mineral N concentration and soil moisture. Short‐term results suggest that the regrowth of F. paniculata following mowing might be N‐limited, first because of N dilution by C increments in the plant tissue, and second, due to low soil mineral N and soil moisture at this time of year. However, despite short‐term effects of mowing on plant growth, C and N content and concentration at the beginning of the following growing season were not affected. Nevertheless, total biomass accumulation at peak standing biomass was largely reduced compared to unmown fields. Moreover, lower C storage capacity at the end of the growing season impacted C allocation to vegetative reproduction during winter, thereby dramatically limiting the horizontal growth of F. paniculata tussocks in the long term. We conclude that mowing reduces the growth of F. paniculata tussocks through both C and N limitation. Such results will help understanding how plant responses to defoliation regulate competitive interactions within plant communities. 相似文献
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Ling&#x;Ying Shuai Shu&#x;Ping Xiao Yan&#x;Ping Xie Xing&#x;Min Chen Xiang&#x;Rong Song Tian&#x;Qiao Fan Yun&#x;Hua Xie Wei Liu 《Ecology and evolution》2022,12(8)
Understanding the roles of ecological drivers in shaping biodiversity is fundamental for conservation practice. In this study, we explored the effects of elevation, conservation status, primary productivity, habitat diversity and anthropogenic disturbance (represented by human population density and birding history) on taxonomic, phylogenetic and functional avian diversity in a subtropical landscape in southeastern China. We conducted bird surveys using 1‐km transects across a total of 30 sites, of which 10 sites were located within a natural reserve. Metrics of functional diversity were calculated based on six functional traits (body mass, clutch size, dispersal ratio, sociality, diet and foraging stratum). We built simultaneous autoregression models to assess the association between the ecological factors and diversity of the local avian communities. Local avian diversity generally increased with increasing habitat diversity, human population density and primary productivity. We also detected phylogenetic and functional clustering in these communities, suggesting that the avian assemblages were structured mainly by environmental filtering, rather than interspecific competition. Compared with sites outside the natural reserve, sites within the natural reserve had relatively lower avian diversity but a higher level of phylogenetic heterogeneity. 相似文献
11.
Nazim Hassan Zhiwei Zhong Deli Wang Yu Zhu Iqra Naeem Abel Bui Ahungu Ho Yi Wan Xiaofei Li 《应用植被学》2023,26(3):e12743
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Invasion of native habitats by alien or generalist species is recognized worldwide as one of the major causes behind species
decline and extinction. One mechanism determining community invasibility, i.e. the susceptibility of a community to invasion,
which has been supported by recent experimental studies, is species richness and functional diversity acting as barriers to
invasion. We used Scandinavian semi-natural grasslands, exceptionally species-rich at small spatial scales, to examine this
mechanism, using three grassland generalists and one alien species as experimental invaders. Removal of two putative functional
groups, legumes and dominant non-legume forbs, had no effect on invasibility except a marginally insignificant effect of non-legume
forb removal. The amount of removed biomass and original plot species richness had no effect on invasibility. Actually, invasibility
was high already in the unmanipulated community, leading us to further examine the relationship between invasion and propagule
pressure, i.e. the inflow of seeds into the community. Results from an additional experiment suggested that these species-rich
grasslands are effectively open to invasion and that diversity may be immigration driven. Thus, species richness is no barrier
to invasion. The high species diversity is probably in itself a result of the community being highly invasible, and species
have accumulated at small scales during centuries of grassland management. 相似文献
14.
In this study, we examined floristic and functional composition of Nardus grassland of the highlands of NE Slovenia. The data-set included 55 relevés, 59 plant species, and 17 plant functional traits (PFT). The TWINSPAN classification resulted in two plant communities; calcifuge species (G1_oligotr) and another group of species characteristic of mesotrophic meadow (G2_mesotr). On the basis of selected PFT 11 out of 17 differ significantly between the groups. Group G1_oligotr had higher community-weighted mean trait values for chamaephytes (G1 = 0.09; G2 = 0.02), geophytes (G1 = 0.03; G2= 0.01), competitors (G1 = 0.43; G2 = 0.41) and plants that start flowering later (G1 = 142.84; G2 = 136.69). On the other side was G2_mesotr represented with more plants that are therophytes (G1 = 0.04; G2 = 0.09), creeping (G1 = 0.01; G2 = 0.12) and short-lived (G1 = 0.04; G2 = 0.11) and have longer flowering period (G1 = 3.24; G2 = 3.60). Differences may reflect the stronger effect of disturbance and eutrophication in G2_mesotr, probably due to intensification of grassland management (grazing) in the region. Our findings are significant in understanding the relative influence of environmental stress and disturbance within Nardus grasslands, and this may have important implications for their conservation management. 相似文献
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Xiaoxia Huang Zhilu Sheng Kejian He Yong Zhang Bin Kang Jiao Ding Dongmei Liu 《Journal of Plant Ecology》2021,14(5):870
人为干扰下的亚高山草甸功能多样性和功能冗余人为干扰程度的加剧会引起植物群落物种多样性和功能多样性的改变,并降低生态系统的稳定性。较高水平的功能冗余对于物种损失引起的生态系统功能和稳定性的改变起到了重要的缓冲作用。然而,关于亚高山草甸植物群落功能冗余对干扰的响应的研究相对较少。本研究的目的是,确定人为干扰下不同退化程度的亚高山草甸,其植物群落功能多样性和功能冗余对干扰的响应特征,及不同物种对功能冗余的贡献程度及其在干扰梯度上的变化规律。研究区位于青藏高原东南缘玉龙雪山上的亚高山草甸。本研究识别出4类干扰强度(无干扰、弱干扰、中度干扰和重度干扰),测定了干扰梯度上的植物物种组成、土壤性质和5个关键的植物功能性状等指标,进一步计算了Simpson多样性指数、功能多样性指数(RaoQ)、功能冗余度、群落的植物功能性状加权平均值(CWM)以及物种水平的功能冗余等指数。研究结果表明,功能多样性和功能冗余在干扰梯度上呈现单峰变化规律,即二者分别在中度干扰、弱干扰下达到最大值。物种多样性在干扰梯度上整体呈下降趋势。随着干扰程度的增加,采取保守生长策略并具有相关性状特征(如较低比叶面积和较高的干物质含量)的物种的丰富度降低,采取资源获取策略并具有相关性状(如低矮植株、较高的比叶面积和较低的干物质含量)的物种增加。不同物种的功能冗余程度存在差异。值得注意的是,一些物种在群落中扮演着独特的功能角色,如无干扰梯度下的网脉橐吾(Ligularia dictyoneura)以及中度和重度干扰梯度下的滇西委陵菜(Potentilla delavayi)。 相似文献
16.
Anthropogenic disturbances have serious impacts on ecosystems across the world. Understanding the effects of disturbance on woodlands, especially in regions where local people depend on these natural resources, is essential for sustainable natural resource management and biodiversity conservation. In this study, we evaluated the effects of anthropogenic disturbance, specifically selective logging of Brachystegia floribunda, on woodlands by comparing species composition, species diversity and functional diversity of woody plants between disturbed and undisturbed woodlands. We combined species data and functional trait data for leaves, fruits and other traits related to resource and disturbance responses to calculate functional indices (functional richness, evenness and divergence) and community‐weighted means of each trait. Shifts in taxonomic species composition were analysed using nonmetric multi‐dimensional scaling. Species composition differed significantly between disturbed and undisturbed woodlands. Tree density was greater in disturbed woodlands, whereas evenness, functional evenness and functional divergence were greater in undisturbed woodlands. In terms of forest cover, selective logging of B. floribunda appeared to have little impact on Miombo woodlands, but some shifts in functional traits, such as the shift from a deciduous to evergreen phenology, may increase the vulnerability of these ecosystems to environmental change, especially drought. 相似文献
17.
Anıl Bahar;Çağatay Tavşanoğlu; 《Ecology and evolution》2024,14(11):e70499
Grazing is a major ecological driver that influences vegetation dynamics globally. We investigated the long-term effects of different grazing regimes on the vegetation structure of the Central Anatolian steppes, a region characterized by its unique convergence of biogeographical influences and historical land use. We employed the spatially explicit FATELAND model to simulate vegetation dynamics over a 50-year period under three distinct grazing scenarios: no grazing, moderate grazing, and overgrazing. Our simulations incorporated a range of plant functional traits to predict changes across five different vegetation types in Central Anatolia, including woodland steppes and treeless steppes. The simulations revealed that moderate grazing supports the diversity and abundance of various plant functional groups, excluding resprouter trees, which flourish under no grazing conditions. In contrast, overgrazing leads to significant reductions in the abundance of perennial forbs and both spiny and non-spiny subshrubs, often resulting in a shift toward grassland dominated by resprouter gramineae or an annual herb-dominated grassland, depending on the initial abundance of gramineae. Our findings highlight the critical role of grazing management in maintaining biodiversity and ecological stability in steppe ecosystems. While moderate grazing can enhance plant functional group diversity, overgrazing significantly threatens the ecological integrity of the Central Anatolian steppes. In conclusion, our modeling approach reveals that the grazing regime is a major driver in shaping the vegetation structure of Central Anatolian steppes. Grazing management strategies that are adjusted to the ecological characteristics and historical context of specific regions are required to prevent degradation and promote sustainable grassland vegetation. 相似文献
18.
Zhiying Liu Taogetao Baoyin Juan Sun Hugjiltu Minggagud Xiliang Li 《Ecology and evolution》2018,8(6):3109-3118
While mowing‐induced changes in plant traits and their effects on ecosystem functioning in semi‐arid grassland are well studied, the relations between plant size and nutrient strategies are largely unknown. Mowing may drive the shifts of plant nutrient limitation and allocation. Here, we evaluated the changes in nutrient stoichiometry and allocation with variations in sizes of Leymus chinensis, the dominant plant species in Inner Mongolia grassland, to various mowing frequencies in a 17‐yr controlled experiment. Affected by mowing, the concentrations of nitrogen (N), phosphorus (P), and carbon (C) in leaves and stems were significantly increased, negatively correlating with plant sizes. Moreover, we found significant trade‐offs between the concentrations and accumulation of N, P, and C in plant tissues. The N:P ratios of L. chinensis aboveground biomass, linearly correlating with plant size, significantly decreased with increased mowing frequencies. The ratios of C:N and C:P of L. chinensis individuals were positively correlated with plant size, showing an exponential pattern. With increased mowing frequencies, L. chinensis size was correlated with the allocation ratios of leaves to stems of N, P, and C by the tendencies of negative parabola, positive, and negative linear. The results of structure equation modeling showed that the N, P, and C allocations were co‐regulated by biomass allocation and nutrient concentration ratios of leaves to stems. In summary, we found a significant decoupling effect between plant traits and nutrient strategies along mowing frequencies. Our results reveal a mechanism for how long‐term mowing‐induced changes in concentrations, accumulations, ecological stoichiometry, and allocations of key elements are mediated by the variations in plant sizes of perennial rhizome grass. 相似文献
19.
Philippe Choler Pierre Denelle François Munoz Jens Kattge Sandra Lavorel Jessy Loranger Bernard Amiaud Michael Bahn Peter M. van Bodegom Henry Brisse Guilhem Debarros Sylvain Diquelou Sophie Gachet Claudy Jolivet Servane Lemauviel‐Lavenant Alexis Mikolajczak Jean Olivier Jenny Ordoñez Patrice de Ruffray Nicolas Viovy Eric Garnier 《Global Ecology and Biogeography》2017,26(10):1138-1152
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降水和生物多样性是维持干旱区荒漠草原生态系统平衡和稳定的关键因素, 研究降水变化背景下荒漠草原植物多样性、微生物多样性以及二者相互关系具有重要的理论和实践意义。本文以宁夏盐池荒漠草原为研究对象, 采用遮雨棚和滴灌技术模拟了5个降水梯度, 分别为正常降雨量的33%、66%、100% (CK)、133%和166% (记为R33, R66, RCK, R133, R166), 全面分析了降水变化对荒漠草原植物多样性和微生物多样性的影响。结果表明: (1)降水减少(R66)会显著降低植物群落的多样性和均匀度, 降水增加(R133)会使植物群落丰富度显著增加(P < 0.05); (2)细菌群落的Shannon-Wiener指数、Simpson指数、Ace指数以及真菌群落的Ace指数随降雨量的增加显著增加, 降水变化对真菌群落的Shannon-Wiener指数和Simpson指数影响显著(P < 0.05); (3)增水处理对土壤微生物群落β多样性有显著影响; (4)细菌与土壤碳氮比、碳磷比之间存在显著正相关关系(P < 0.05), 真菌与土壤碳氮比、碳磷比及氮磷比之间均存在极显著正相关关系(P < 0.01); (5)植物群落多样性与细菌Shannon-Wiener指数显著正相关, 与细菌Simpson指数、Ace指数及真菌Ace指数显著负相关(P < 0.05)。因此, 降水变化对荒漠草原植物多样性和微生物多样性产生了显著影响, 且二者之间存在紧密关联, 这不仅为模拟和预测荒漠草原生态系统对气候变化的响应和反馈提供借鉴, 也为该地区的生态保护和恢复提供了科学依据。 相似文献