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1.
Ayako Shimono Huakun Zhou Haihua Shen Mitsuru Hirota Toshiyuki Ohtsuka Yanhong Tang 《Journal of Plant Ecology》2010,3(1):1
Aims To describe the biodiversity patterns of plants along an altitudinal gradient on the Qinghai-Tibetan Plateau and to clarify the bias in plant specimen records at high altitude.Methods We conducted a large-scale investigation of vegetation at a wide range of altitudes, focusing on a high-altitudinal range (3?200–5?200 m) at different locations on the Qinghai-Tibetan Plateau. We then compared the altitudinal distribution of plant species obtained from our field investigation with that in plant specimen records from published sources and an online database.Important findings Our data provide evidence that altitude plays a large role in regulating species composition on the Qinghai-Tibetan Plateau. We could not, however, detect a clear relationship between altitude and species richness, although a weak monotonically increasing trend of richness was detected with increasing altitude. According to specimen records, most species have been sampled at a wide range of altitudes, and the average range of 145 species is>2?000 m. Despite this wide range, more than half of the species we observed were at higher altitudes than the specimen records indicate. High-altitude areas have probably been so poorly sampled that only a small fraction of the resident species has been recorded. This study clearly shows the regional bias of specimen records in the Qinghai-Tibetan Plateau. 相似文献
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高黎贡山种子植物物种丰富度沿海拔梯度的变化 总被引：23，自引：4，他引：23
物种丰富度沿海拔梯度的分布格局成为生物多样性研究的热点。为探讨中尺度区域物种丰富度沿海拔梯度的分布,本文以高黎贡山为研究对象,利用该地区的地方植物志资料,结合通过GIS生成的区域数字高程模型(DEM)数据,分析了该区域全部种子植物和乔木、灌木、草本三种生活型种子植物物种丰富度的垂直分布格局以及物种密度沿海拔梯度的变化特征。结果表明：(1)全部种子植物和不同生活型植物物种丰富度随着海拔的升高呈现先增加后减小的趋势,最大值出现在海拔1500—2000m的范围;(2)物种密度与海拔也呈现单峰曲线关系;(3)物种丰富度和物种密度分布格局的形成主要受海拔所反映的水、热状况组合以及物种分布的边界影响。 相似文献
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基于等面积高度带划分的贺兰山维管植物物种丰富度的海拔分布格局 总被引：6，自引：0，他引：6
山地植物物种丰富度海拔分布格局是生物多样性研究的热点之一。以往研究中一般将山体划分为等海拔间距的高度带, 以分析物种丰富度的垂直格局, 其缺陷在于因各高度带面积不相等而可比性下降。为消除面积不相等的影响, 作者利用数字高程数据(DEM, Digital Elevation Model)在地理信息系统(GIS)工具支持下, 尝试将贺兰山(海拔范围1,300–3,500 m)划分为等面积的数个高度带, 从而分析其物种丰富度的海拔格局。结果表明: (1) 贺兰山物种丰富度呈现为单峰式海拔格局, 峰值出现在海拔2,000 m附近。(2) 逐步回归分析显示, 坡度异质性是解释物种丰富度海拔分布格局的最优因子。高度带的坡度异质性越大, 意味着地形的起伏变化越大, 反映出生境类型越趋多样化, 从而可维持多个物种的共存。(3) 贺兰山植物物种丰富度在海拔2,000 m 附近达到峰值, 可能与植被演变历史、气候条件、地形复杂度、生态过渡带和中间膨胀效应的共同影响有关。(4) 对山体进行等面积划带, 可直接消除面积不相等带来的影响, 与等间距划带的方法相比, 尤其在物种海拔分布信息准确度较高时更具优势。 相似文献
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Aim To study the altitudinal variation of ground spiders (Araneae, Gnaphosidae) of Crete, Greece, as far as species composition, species richness, activity and range of distribution are concerned. Location Altitudinal zones (0–2400 m) along the three main mountain massifs of the island of Crete. Methods Thirty‐three sampling sites were located from 0 to 2400 m a.s.l. on Crete, and sampled using pitfall traps. Material from the high‐activity period of Gnaphosidae (mid‐spring to mid‐autumn) was analysed. Sampling sites were divided into five altitudinal zones of 500 m each. Statistical analysis involved univariate statistics (anova ) and multivariate statistics, such as multidimensional scaling (MDS) and cluster analysis (UPGMA) using binomial data of species presence or absence. Results Species richness declines with altitude and follows a hump‐shaped pattern. The activity pattern of the family, as a whole, is not correlated with altitude and is highly species‐specific. In the highest zone, both species richness and activity decline dramatically. The altitudinal range of species distribution increases with altitude. On the Cretan summits live highly tolerant lowland species and isolated residents of the high mountains of Crete. Two different patterns of community structure are recorded. Main conclusions Communities of Gnaphosidae on Crete present two distinct structures following the altitudinal gradient, these being separated by a transitional zone between 1600 and 2000 m. This study supports previous results which show a hump‐shaped decline in species richness of Gnaphosidae along altitudinal gradients, leading to a peak at 400–700 m, where an optimum of environmental factors exists. This makes this zone the meeting point of the often opportunistic lowland species with the older and most permanent residents of the island. Rapoport's rule on the positive correlation of the altitudinal range of species distributions with altitude is also supported. The high activity recorded for the species that persist on the high mountains of Crete is indicative of a tolerant arachnofauna, and is considered to result from relaxation of competitive interactions with other species. This is related to a reduction in species numbers, shortening of the activity period on high mountains and the unique presence of high mountain species that thrive only there. As shown in our study, strategies to cope with altitude are species‐specific. Therefore, there cannot exist one single model to describe how animals react to the change in altitude, even under the same environmental conditions. 相似文献
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滇西北地区是我国三大特有物种分化中心之一。作者利用地方植物志资料,结合数值高程模型(DEM)数据,研究了云南丽江地区种子植物物种丰富度的垂直分布格局,并分析了面积和中间膨胀效应(mid-domaineffect)对该格局的影响。研究结果表明:随着海拔的升高,各海拔段面积呈先增加后下降的分布格局;物种丰富度、物种密度和中间膨胀效应的物种丰富度预测值在海拔梯度上均呈单峰型变化格局。面积和中间膨胀效应对丽江地区物种丰富度的垂直分布格局有着显著的影响。其中,面积起主要作用,对物种丰富度的变异解释百分率达80.2%,而中间膨胀效应的影响作用相对较小,仅占11.3%。 相似文献
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基于丛枝菌根(Arbuscular mycorrhizal,AM)真菌孢子形态学的鉴定,对沿不同海拔(4584、4628、4744、4880、4956 m)梯度采集的高寒草原建群植物根际土壤样品进行了分析。结果表明,高寒草原AM真菌属、种构成均较简单,Acaulospora、Claroideoglomus、Funneliformis、Glomus属见于各海拔梯度,海拔4744 m地带未见Pacispora属,海拔4744、4956 m地带无Scutellospora属分布,Rhizophagus属仅见于海拔4584 m地带。随海拔上升,AM真菌种数、物种丰度均呈显著下降;海拔4584—4880 m范围Shannon-Weiner指数(H)无显著差异,但在最高海拔时显著下降;优势种种数及所占比例与海拔梯度则呈显著正相关(Funneliformis geosporum、Claroideoglomus claroideum为不同海拔梯度优势种);沿海拔梯度,孢子密度基本呈单峰分布格局,峰值出现在海拔4744 m地带;海拔梯度对菌根侵染效应影响显著,菌根侵染率、侵染强度和丛枝丰度随海拔上升均呈显著下降趋势;不同海拔梯度高寒草原AM真菌群落相似度(Sorensen相似性系数0.821—0.969)较高,并在总体上表现出随海拔梯度增大而降低的趋势。土壤pH值、有效磷、有机碳、海拔对AM真菌的群落分布均产生显著影响,尤以海拔的影响最为显著。研究结果对预测高寒草原微生物的作用与影响,以及高寒草原环境对全球变化的响应等提供了理论依据。 相似文献
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Johannes Måsviken;Love Dalén;Karin Norén;Fredrik Dalerum; 《Journal of Biogeography》2024,51(11):2184-2197
Mountains are often used to study how environmental factors influence biodiversity. However, we have limited understanding of the processes causing biodiversity variation in mountains and whether such processes vary across trophic levels and spatial scales. The aim of this study was to evaluate (i) whether community assembly processes varied along elevational gradients, (ii) whether there were differences in such variation between primary producers (vascular plants) and secondary consumers (spiders) and (iii) whether there were scale dependencies in any elevational variation in community assembly. 相似文献
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物种丰富度和种域的海拔梯度格局及其形成机制一直是生物地理学和生物多样性研究的重点.海拔Rapoport法则认为,物种丰富度随海拔升高而逐渐降低,种域逐渐变宽.本文分析了秦岭小陇山国家级自然保护区维管植物物种丰富度及其种域宽度的海拔梯度格局;采用4种常用方法,验证不同类群、不同生长型和不同阶元的物种丰富度与其分布中点间的关系,并检验其是否支持海拔Rapoport法则.结果表明: 除窄域种外,秦岭小陇山维管植物物种丰富度随海拔升高呈先升后降的单峰分布格局;狭域种主要分布在低海拔和高海拔段,低海拔段的丰富度高于高海拔段;物种海拔分布宽度与海拔关系因不同类群和验证方法而异,随分类阶元的增大更容易支持Rapoport法则,这可能与不同分类阶元所占据的生态位不同有关;被子植物的平均种域呈单峰分布格局,蕨类植物和裸子植物的种域海拔梯度格局无明显规律;藤本植物平均种域随海拔升高而变宽,灌木能适应不同的环境条件,因此,灌木分布对海拔梯度的变化不敏感.Pagel验证方法最容易支持Rapoport法则,Stevens方法次之,中点法受中域效应的影响物种平均种域分布呈单峰分布格局而不支持Rapoport法则,逐种法受散点图分布格局的影响线性模型拟合结果解释力很低. 相似文献
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福建黄岗山东南坡和西北坡乔木物种多样性及群落特征的垂直变化 总被引：23，自引：0，他引：23
利用福建黄岗山东南坡30个样方和西北坡13个样方的资料,研究该地区乔木物种丰富度的垂直变化;东南坡共记录到乔木物种151种,隶属于42科73属;西北坡102种,隶属于32科54属。两坡面的乔木树种组成相差不大。物种丰富度随海拔的变化趋势是：随海拔升高,科、属、种的数量呈下降的趋势;东南坡科、属、种的数量在海拔800—1000m达到最大值,西北坡在海拔1500—1600m达到最大值。东南坡乔木物种Shannon—Wiener指数(H’)与海拔呈负相关;西北坡在海拔1200—1800m范围内H’高于东南坡;Screnson指数(IAc)在不同植被类型交替时出现上下波动,从常绿阔叶林向针阔混交林转化时,物种更替强烈,Screnson指数明显下降。乔木物种生长特征的分析表明,最大树高(Hmax)和最大胸径(DBHmax)出现在中海拔,在相同海拔范围内西北坡的Hmax和DBHmax高于东南坡;东南坡Hmax和DBHmax的峰值出现在海拔800—900m,西北坡出现在海拔1800m。东南坡立木密度在海拔1500m处达最高值,而西北坡立木密度变化不明显,仅在海拔1900m以上明显下降。将全部乔木种划分为常绿阔叶、针叶和落叶阔叶等三种生活型,分析不同生活型的生长特征发现,常绿阔叶种类的胸高断面积和(total basal area,TBA)在低海拔占比例大;针叶种类沿海拔出现两个峰值,与分布两种不同针叶林种类有关;落叶阔叶林的TBA在各海拔段均占一定比例,但在西北坡的比例要高于东南坡。两坡三种生活型的TBA沿海拔梯度变化特征基本上相似。 相似文献
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Bryan L. Foster 《Ecology letters》2001,4(6):530-535
An important goal in ecology is to discern under what habitat conditions community structure is primarily regulated by local ecological interactions and under what conditions community structure is more regulated by the pool of available colonists. I conducted a seed addition experiment in successional grassland to evaluate the relative significance of neighbourhood biotic interactions and propagule availability in regulating plant colonization and species richness along a natural gradient of grassland productivity. In undisturbed field plots, seed additions of 34 species led to an increase in species richness in locations of low productivity, an effect that declined in magnitude as productivity increased. In disturbed plots, seed additions led to a relatively constant increase in species richness at all levels of productivity. The results support the hypothesis that the role of propagule availability in regulating colonization dynamics and species richness declines in significance relative to local-scale competitive interactions as habitat productivity increases. 相似文献
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利用 5月份温带草原鸟类繁殖期 ,在荒漠草原、草原、湿地、沙地和山地等植被 ,选取 1 1个面积 1 0 0 hm2 ( 50 0 m×2 0 0 0 m)同样大小的样区 ,由 3人各隔 1 50 m作平行的穿越线调查 ,并记录所见鸟类的种类与数量。同时 ,也在每一样区任取面积 1 m2 之植被样方 ,记载样方内植物的种类、垂直高度、覆盖度和植物鲜重。调查结果显示草原繁殖鸟类的种类不多 ,在无树的荒漠草原植被是 4～ 6种 ,草原植被在 5～ 8种之间 ,湿地植被 1 5种 ;在有树的沙地植被是 9～ 1 2种 ,山地植被 6种。鸟种多样性和丰富度指数不大 ,由大而小依序是沙地植被、湿地植被、山地植被、草原植被、荒漠草原植被 ;密度也不高 ,由大而小依序是无树草原的湿地植被、草原植被、荒漠草原植被 ,而后是有树草原的沙地植被、山地植被。鸟类食性分布方面 ,荒漠草原和草原植被以食杂性鸟类为优势 ;湿地植被以食虫性鸟类为多 ;沙地植被以食杂与食肉性鸟类为胜 ;山地植被以食虫和食杂性鸟类较多 ,并增加一些食肉性鸟类。 相似文献
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The Brazilian high altitude grasslands are important biodiversity centers that contribute to human well‐being far outside their boundaries. They host many vulnerable species that may go locally extinct as a result of small changes in the environment. Performing studies on local species distribution is important to guide biodiversity conservation in these areas. This study aimed to characterize a high altitude grassland plant community along an elevation gradient in southeastern Brazil. Simple logistic regression, chi‐squared tests and indicator species analysis were performed to investigate respectively whether: 1) the occurrence of botanical families was related to the altitude; 2) the richness and abundance of life forms varied along the gradient and 3) there were populations associated with specific altitudinal belts. Rubiaceae and Polygalaceae had higher occurrence probability at higher altitudes. Hemicryptophytes and chamaephytes seem to be the most favored life forms under local extreme conditions such as low temperatures and drought. The vegetation spectra varied significantly along the gradient, highlighting the major role of the turnover of habitats on a local scale for the underlying patterns of species distribution. Upper elevations encompassed a high number of indicator species, and further analyses of indicator species of high altitude grasslands will provide clues about adaptability of local species, important to consider in ecosystem management and conservation. 相似文献
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Nihaib Flores&#x;Galicia Irma Trejo Neptalí Ramírez&#x;Marcial 《Ecology and evolution》2021,11(10):5690
The study of changes in species richness and composition along rivers has focused on large spatial scales. It has been ignored that in different sections of the river (high mountain area, middle zone, and mouth of the river) the specific environmental conditions can generate different longitudinal patterns of the species richness and composition. In this study, we determine whether species richness and composition of the riparian plant communities change along a mountain river and whether these changes are related to environmental variables. We expect an increase in species richness and turnover along the river, that the upstream communities would be a subset of the downstream communities, and that such would be related to edaphic and hydrologic conditions. To test this, we sampled three strata of the riparian vegetation (upper: individuals with <1 cm of ND, middle: individuals with >1 cm of ND, low: individuals with >1 m tall) in a set of 15 sites that we place along a mountain river. Additionally, we recorded topographic, hydrological, morphological, and soil variables. We performed correlation analyzes to determine whether changes in species richness and turnover were related to increased distance to the origin of the river. Also, we obtained the nestedness and evaluated the importance of environmental variables with GLM, LASSO regression, and CCA. With the increase in distance, the species richness decreases in the upper stratum, but not in the middle and the low stratum (although the highest values were observed near the origin of the river), the turnover increase in all strata and the upstream communities were not a subset of the downstream communities. The changes in species richness and composition were related to topographic (altitude), hydrological (flow), and edaphic (conductivity and pH) variables. Our results indicate that at small spatial scales the patterns of richness and composition differ from what has been found at larger spatial scales and that these patterns are associated with environmental changes in the strong altitude gradients of mountain rivers. 相似文献
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Yuguang Ke Qiang Yu Hongqiang Wang Yi Zhao Xiaotong Jia Yadong Yang Yunlong Zhang Wei Zhou Honghui Wu Chong Xu Tao Sun Yingzhi Gao Anke Jentsch Nianpeng He Guirui Yu 《Global Change Biology》2023,29(4):1054-1061
Atmospheric nitrogen (N) deposition is composed of both inorganic nitrogen (IN) and organic nitrogen (ON), and these sources of N may exhibit different impacts on ecosystems. However, our understanding of the impacts of N deposition is largely based on experimental gradients of INs or more rarely ONs. Thus, the effects of N deposition on ecosystem productivity and biodiversity may be biased. We explored the differential impacts of N addition with different IN:ON ratios (0:10, 3:7, 5:5, 7:3, and 10:0) on aboveground net primary productivity (ANPP) of plant community and plant diversity in a typical temperate grassland with a long-term N addition experiment. Soil pH, litter biomass, soil IN concentration, and light penetration were measured to examine the potential mechanisms underlying species loss with N addition. Our results showed that N addition significantly increased plant community ANPP by 68.33%–105.50% and reduced species richness by 16.20%–37.99%. The IN:ON ratios showed no significant effects on plant community ANPP. However, IN-induced species richness loss was about 2.34 times of ON-induced richness loss. Soil pH was positively related to species richness, and they exhibited very similar response patterns to IN:ON ratios. It implies that soil acidification accounts for the different magnitudes of species loss with IN and ON additions. Overall, our study suggests that it might be reasonable to evaluate the effects of N deposition on plant community ANPP with either IN or ON addition. However, the evaluation of N deposition on biodiversity might be overestimated if only IN is added or underestimated if only ON is added. 相似文献