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1.
《植物生态学报》2016,40(9):861
Aims Spatial distribution patterns and formation mechanisms of species diversity are fundamental issues in community ecology. The objectives of this study are to assess the species diversity patterns at the different spatial scales in Jianfengling, Hainan Island, China.
Methods Based on the dataset from the 60 hm2 plot in the tropical montane rain forest in Jianfengling, Hainan Island, the spatial distribution patterns of species richness, species abundance, Shannon-Wiener, Simpson and Pielou’s evenness indices were analyzed at six spatial scales, including 5 m × 5 m, 10 m × 10 m, 20 m × 20 m, 40 m × 40 m, 100 m × 100 m, and 200 m × 200 m, respectively.Important findings
Results showed that spatial distribution patterns of species richness, species abundance and Shannon-Wiener index were much more obviously changed with the spatial scales than Simpson and Pielou’s evenness indices. Change of variance of the species richness with the increase of spatial scales was unimodal, which had the maximum value at the 20 m × 20 m scale. Variance of the species abundance showed a linear relationship with the increase of spatial scales. The positive relationship between species richness and abundance gradually decreased and even disappeared with the increase of sampling scales, which may be correlated with the increase of habitat heterogeneity. The effects of spatial scales on Shannon-Wiener, Simpson, and Pielou’s evenness indices may be also correlated with the composition of rare species in the plot.  相似文献   

2.
物种多样性的空间分布格局和维持机制是群落生态学的基本问题。为了探讨海南尖峰岭地区物种多样性空间分布格局的尺度效应, 以海南尖峰岭热带山地雨林60 hm2样地为研究对象, 分析了物种丰富度、物种多度、Shannon-Wiener指数、Simpson指数以及Pielou均匀度指数随6个空间取样尺度(5 m × 5 m、10 m × 10 m、20 m × 20 m、40 m × 40 m、100 m ×100 m、200 m × 200 m)的变化。结果表明: 相比Simpson指数和Pielou均匀度指数, 物种丰富度、多度以及Shannon-Wiener指数具有更为明显的空间尺度效应; 物种丰富度的方差随取样尺度增加呈现单峰分布特征, 并且在20 m × 20 m尺度上达到最大值, 而物种多度的方差随取样尺度的增加而增大; 物种丰富度和多度的正相关性随着取样尺度的增加逐渐减小甚至消失, 这可能与随取样尺度增加生境异质性增加有关; 取样尺度对3个物种多样性指数空间分布的影响可能与研究区域内稀有种的组成有关。  相似文献   

3.
This paper examines the question of whether hunter-gatherers could live in the tropical rain forest of Peninsular Malaysia without access to cultivated foods. It considers the wild food sources used by the Batek De', a contemporary foraging-trading group of Kelantan state, historical and ethnohistorical evidence concerning the Batek economy in the past, and archeological evidence for independent foraging in the Pleistocene and early Holocene. The conclusion reached is that small nomadic groups of foragers can live off wild resources alone in that environment and have done so in the past, although trade for agricultural produce makes life much easier. This suggests that nonseasonal tropical rain forests vary in their potential for supporting human foraging, depending upon the particular species of plants and animals present.  相似文献   

4.
Methane fluxes were measured, using static chambers, across a disturbance gradient in a West African semi-deciduous humid forest. Soil-feeding termite biomass was simultaneously determined, in an attempt to examine its influence on the net soil-atmosphere exchange of CH4. CH4 emission rates from individual termite species were determined under laboratory conditions, permitting the gross production of CH4 to be compared with net fluxes to the atmosphere. Both net CH4 oxidation(-) and emission were observed, and CH4 fluxes ranged from – 24.6 to 40.7 ng m–2 s–1. A statistically significant relationship between termite biomass and CH4 flux was observed across the forested sites such that: CH4 flux (ng m–2 s–1) = 4.95 × termite biomass (gm–2)–10.9 (P < 0.001). Rates of CH4 oxidation were on average 60% smaller at the clearfelled and Terminalia plantation sites than at the near-primary forest site. Two of the disturbed sites were net CH4 sources during one of the sampling periods. Disturbance of tropical forests, resulting in a decrease in the CH4 sink capacity of the soil, may therefore increase the contribution of termite-derived CH4 to the atmosphere. Measurements from the mounds of the soil-feeding termites Thoracotermes macrothorax and Cubitermes fungifaber from the old plantation site gave a CH4 emission of 636 and 53.4 ng s–1 mound–1, respectively. The forest floor surrounding the mounds was sampled in three concentric bands. Around the mound of T. macrothorax the soil was a net source of CH4 estimated to contribute a further 148 ng s–1. Soil surrounding the mound of C. fungifaber was mostly a net sink. The mounds of soil-feeding termites are point sources of CH4, which at the landscape scale may exceed the general sink capacity of the soil, to an extent dependent on seasonal variations in soil moisture and level of disturbance.  相似文献   

5.
海南岛霸王岭热带低地雨林树木的空间格局   总被引:1,自引:1,他引:1       下载免费PDF全文
树木空间格局及其形成过程是物种共存及生物多样性维持机制研究的一个重要方面。该文以海南岛两个1 hm 2的典型热带低地雨林老龄林森林动态样地为基础, 通过4个点格局模型(均质Poisson过程、异质Poisson过程、均质Thomas过程和异质Thomas过程)模拟扩散限制和生境异质性作用对树木空间分布格局的影响, 并分析不同空间尺度下(< 2 m, 2-5 m, 5-10 m, 10-15 m, 15-20 m和20-25 m)不同作用的相对重要性。结果表明: 热带低地雨林的所有树木总体上呈现聚集分布的空间格局, 随着尺度的增大, 聚集强度逐渐减小。树种在模拟空间分布格局最优模型中的比例由高到低分别是: 均质Thomas过程, 均质Poisson过程、异质Thomas过程和异质Poisson过程。扩散限制作用是形成热带低地雨林树木空间分布格局最重要的生态过程, 其次是完全随机作用以及生境异质性和扩散限制的联合作用, 而生境异质性的作用最小。不同空间尺度上模拟各树种空间分布格局的最优模型比例差异显著, 扩散限制作用能够在多数空间尺度上模拟多个树种的空间分布格局, 其次为随机作用; 生境异质性和扩散限制的联合作用主要在小尺度(0-5 m)影响树种分布, 而生境异质性在较大尺度(15-25 m)上影响树种的空间分布格局。  相似文献   

6.
Abstract In October 1999, patches of dead and dying trees were identified in rainforest vegetation throughout the Tully Falls area in north Queensland, Australia. Previous incidents of patch death in the region had been attributed to Phytophthora cinnamomi. The distribution of P. cinnamomi was assessed by testing for its presence in seven sites displaying signs of dieback and seven sites that appeared healthy. Each site was a circular quadrat, 20‐m radius (total area = 1256.6 m2). Within each quadrat, two perpendicular line transects were constructed. A single soil sample (250 g) was taken at the centre point and at 1‐m intervals along each transect. All soil samples were tested for the presence of P. cinnamomi using a combination of lupin baiting, subsequent culturing and microscopic identification. Of the 1134 samples, 783 recorded positive responses. The mean number of positive responses was not significantly greater in patch death sites than in control sites, suggesting that at this scale of resolution the distribution of P. cinnamomi was uniform. However, at spatial scales of 1‐m intervals across transects the distribution of P. cinnamomi was random.  相似文献   

7.
Rain forests on Borneo support exceptional concentrations of endemic insect biodiversity, but many of these forest-dependent species are threatened by land-use change. Totally protected areas (TPAs) of forest are key for conserving biodiversity, and we examined the effectiveness of the current TPA network for conserving range-restricted butterflies in Sabah (Malaysian Borneo). We found that mean diurnal temperature range and precipitation of the wettest quarter of the year were the most important predictors of butterfly distributions (= 77 range-restricted species), and that species richness increased with elevation and aboveground forest carbon. On average across all species, TPAs were effective at conserving ~43% of species’ ranges, but encompassed only ~40% of areas with high species richness (i.e., containing at least 50% of our study species). The TPA network also included only 33%–40% of areas identified as high priority for conserving range-restricted species, as determined by a systematic conservation prioritization analysis. Hence, the current TPA network is reasonably effective at conserving range-restricted butterflies, although considerable areas of high species richness (6,565 km2) and high conservation priority (11,152–12,531 km2) are not currently protected. Sabah's remaining forests, and the range-restricted species they support, are under continued threat from agricultural expansion and urban development, and our study highlights important areas of rain forest that require enhanced protection.  相似文献   

8.
西双版纳热带山地雨林生物量研究   总被引:3,自引:0,他引:3  
观测了西双版纳山地气候,建立了山地雨林生物量回归方程,调查了海拔1 100~1 820 m范围5块样地(面积0.16~0.25 hm2)的热带山地雨林生物量。结果表明,海拔1 105和1 610 m的年平均温度分别为20.1和16.6℃,年降雨量分别为1 659和2 011 mm,旱季(11~4月)降雨量分别为295和283mm,年平均相对湿度分别为81%和84%;5块样地生物量变化为256.4~368.6 t.hm-2,平均为312.6t.hm-2,其中乔木占97.1%、木质藤本占1.2%、幼树和灌木占1.3%、草本和幼苗占0.4%;采用热带季节雨林生物量回归方程估计山地雨林生物量,会使得总生物量以及树干和树根生物量高估38.3%~61.5%,树枝生物量低估7.6%~30.8%。可见,西双版纳山地海拔增加导致雨季降雨量增加,山地雨林生物量较热带季节雨林降低32.6%,季节雨林生物量方程不适用于山地雨林。  相似文献   

9.
林隙是森林中一种普遍存在的小尺度森林干扰形式,对促进森林更新和循环演替具有重要作用。对热带喀斯特森林的林隙干扰目前还了解不多。该文采用Worldview-3高空间分辨率遥感影像结合地面调查,对弄岗喀斯特季节性雨林15 hm~2样地林隙干扰特征及其空间分布规律进行了研究。结果表明:样地内共解译到305个林隙,林隙的密度约为每公顷20个,林隙大小的变化范围为10~371 m~2,平均大小为52.3m~2,林隙面积占森林面积的10.6%;林隙在0~50 m尺度整体表现出聚集分布格局;林隙空间分布与大树(DBH≥10 cm)存在显著空间关联,与小树(DBH10 cm)和枯立木无显著空间关联;不同生态因子对林隙的数量分布和基本结构影响不同,对林隙数量分布影响最显著的包括凹凸度、干旱度指数、丰富度,而坡向、海拔、丰富度对林隙大小有显著影响,海拔、岩石裸露度、地形湿润度指数、干旱度指数、多度等5个生态因子对林隙周长有显著影响。研究结果表明林隙在喀斯特季节性雨林普遍存在,林隙的空间分布与特征存在着地形分异特征,是喀斯特独特的地质地貌和生境条件与喀斯特森林自身生物学特性综合作用的结果。  相似文献   

10.
关帝山林区景观要素空间分布及其动态研究   总被引:37,自引:5,他引:37  
在ARC/INFO支持下,应用GIS技术结合景观生态学原理,从一个侧面对关帝册林森林景观空间分布格局进行了分析研究,提出了一套适用于森林景观空间格局分析方法和指标,揭示了研究地区森林景观空间分布动态的一些基本规律,研究结果表明,在GIS支持下,通过网格样方全景观取样,采用基准面积样方取值法确定样方观测值,分别景观要素计算Morisita指数或E-指标,可以对研究对象的空间分布特征做出客观的分析,并  相似文献   

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应用序列指示条件模拟算法模拟森林类型空间分布   总被引:4,自引:2,他引:4  
森林类型的空间分布是进行森林景观格局研究的基础和先决条件。当前林业实际生产过程中 ,森林分布图的获得要么具有很强的主观性 ,要么受环境因素的制约。空间统计学可以描述事物在空间上的分布特征 ,条件模拟算法是空间统计学中进行空间插值的一种有效手段。森林类型是一个区域化的分类变量 ,在研究区内可能存在森林类型破碎化严重情况 ,为此本文选用分类变量的序列指示条件模拟算法来模拟森林类型的空间分布。文中介绍了序列指示条件模拟算法的原理、计算步骤、优点及适用性 ,以东北汪清林业局局级样地为材料 ,应用序列指示条件模拟算法对汪清林业局森林类型空间分布进行模拟 ,模拟结果与森林经理调查得到的森林分布图相比较 ,模拟精度达到 73.80 %。精度分析结果表明 ,以样地为材料 ,应用序列指示条件模拟算法 ,可以作为获得森林类型分布图的一个有效途径  相似文献   

13.
The geographical characteristics of a total of 1839 forest fragments surrounded by sugar cane fields were studied in the Brazilian Atlantic rain forest region of the northeastern state of Pernambuco. The size and shape of the fragments as well as inter-fragment distances and the effects of varying edge width were examined using a geographical information system. The analyses show that the fragments are relatively small and close to each other. Approximately 48% of the rain forest fragments are <10 hectares, while only about 7% are >100 hectares. Forest fragments are close to each other, as fragments located 50m or less apart formed groups that included ca. 50% of the total forest area. At 350m inter-fragment distance, 98% of the rain forest area was included in groups of fragments. Due to the small size and irregular shape of the fragments, the total area of edge zone exceeds that of the interior habitat when the edge width is ca. 60m. At an edge width of 300m ca. 94% of the total fragment area is edge zone. For conservation purposes, ways of establishing networks of forest fragments connected by corridors and stepping stone fragments are demonstrated using GIS. Simulations using these techniques show that reforestation of sugar cane fields between the forest fragments would considerably increase the area of interior forest habitat and connectivity between fragments.  相似文献   

14.
陕西不同林区栓皮栎种群空间分布格局及动态的比较研究   总被引:32,自引:1,他引:32  
在陕西黄龙山区、秦岭北坡和巴山北坡设置 1 0× 1 0 m2 样方 98个 ,应用相邻格子法进行每木调查获得野外资料 ,采用离散分布理论拟合检验、t检验和聚集强度测定的方法 ,对栓皮栎种群空间分布格局及动态进行了对比研究。结果表明 :1栓皮栎种群在黄龙山区为奈曼 A型分布 ,秦岭北坡和巴山北坡为负二项分布 ;聚集强度 ,秦岭北坡 >黄龙山区 >巴山北坡。 2在秦岭和巴山北坡中低海拔地区 ,种群为负二项分布 ,随海拔升高 ,秦岭北坡趋向随机分布 ,巴山北坡趋向均匀分布 ;两地种群聚集强度随海拔升高呈“低 -高 -低”的变化格局。3秦岭北坡 1~ 1 0年生种群的聚集度最大 ,随着年龄增加 ,聚集强度逐渐下降 ;而黄龙山区和巴山北坡种群的聚集强度随年龄增加而增强。栓皮栎种群生物学和生态学特性与环境因素共同作用是种群分布格局形成的主要因素 ,人为干扰对分布格局具有重要影响。根据环境条件和种群动态规律实行不同的经营方式是实现栓皮栎林持续利用的根本性措施  相似文献   

15.
浙江省森林信息提取及其变化的空间分布   总被引:4,自引:0,他引:4  
姜洋  李艳 《生态学报》2014,34(24):7261-7270
如何利用遥感技术提取森林信息是遥感应用的重要领域之一。以不同时相的Landsat TM/ETM+为数据源,采用面向对象和基于多级决策树的分类方法得到浙江省2000年、2005年以及2010年的森林植被覆被图。经实地采样点验证,2010年分类精度达到92.76%,精度满足要求。介绍了浙江森林信息的快速提取方法,即统计不同森林类型的Landsat TM影像原始波段和LBV变换值以及各种植被指数在各时相上的差异,经过C5决策树训练,选取合适的规则和阈值实现森林信息的提取。结果表明,面向对象分割与决策树算法结合可以作为森林信息提取的有效方法。最后,通过对3期森林专题图进行空间叠加分析,得到了森林资源动态变化的空间分布,并以此为基础对林地变化的类型及原因进行分析,结果显示浙江省森林资源变化主要分布在浙西北山区、浙中南山区以及沿海地带,这一结果可以为有关部门的决策提供依据。  相似文献   

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林木分布格局类型的角尺度均值分析方法   总被引:32,自引:0,他引:32  
空间结构是森林的重要特征 ,它反映了森林群落内物种的空间关系即林木的分布格局及其属性在空间上的排列方式。林木分布格局是种群生物学特性、种内与种间关系以及环境条件综合作用的结果 ,是种群空间属性的重要方面 ,也是种群的基本数量特征之一。角尺度是一个刻画森林空间结构的新参数 ,通过描述相邻木围绕参照树的均匀性来进行林木分布格局的判定。与其他的描述分布格局的指数相比 ,角尺度具有调查费用低、结果的体现既可用均值也可用频率分布的形式 ,对复杂结构具有很强的解析能力 ,在结构复杂天然林的可持续经营中将发挥十分重要作用。为在实践中快速准确地应用这一新的空间结构参数 ,研究分析了 2 0 0 0个模拟林分的角尺度均值 ,并用 3倍标准差原理提出了林木分布格局类型的角尺度均值评判标准 ,指出随机分布时角尺度均值范围为 [0 .4 75 ,0 .5 17],大于 0 .5 17时为团状分布 ,而小于 0 .4 75时为均匀分布。这一标准的提出进一步完善了角尺度理论  相似文献   

17.
In pursuance of economic growth and development, logging has exhausted the natural timber resource in the tropical rainforest of Sabah, Malaysia. Realizing the forest depletion, the Sabah Forestry Department, with technical support from the German Agency for Technical Cooperation, begun developing a management system with the intent of managing all commercial forest reserves in a way that mimics natural processes for sustainable production of low volume, high quality, and high priced timber products in 1989. As dictated by a forest management plan based on forest zoning, about 51,000 ha of the entire area is set aside for log production and 4,000 ha for conservation in Deramakot Forest Reserve, Sabah, Malaysia. This Forest Management Plan has served as the blueprint for operational work and biodiversity conservation in Deramakot to the present. A strict protection area is set aside for biodiversity conservation within the reserve. A reduced-impact logging system is being employed for harvesting with minimal impacts on the physical environment. Deramakot Forest Reserve was certified as “well managed” by an international certification body, the Forest Stewardship Council, in 1997 and is the first natural forest reserve in Southeast Asia managed in accordance with sustainable forestry principles. In addition to providing a "green premium," certification provides easier market access, evidence of legality, multi-stakeholder participation, conservation of biodiversity and best forest management practices, particularly reduced-impact logging techniques. Deramakot Forest Reserve is the flagship of the Sabah Forestry Department and serves as a symbol of what can be achieved with political support and institutional commitment.  相似文献   

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海南五指山热带山地雨林植物物种多样性研究   总被引:35,自引:4,他引:35  
王指山热带山地雨林的物种种类十分丰富,在1hm^2样地中共出现54个科,100个属的乔木树种177种,1337个个体。区系地理分析表明属的分布区类型以热带分布型成分占优,为89.0%,充分体现了五指山山地雨林的热带性质。多样性指数分析结果为:样地1Margalef指数17.822,Shannon-Wiener指数5.621,均匀度0.823,Simpson指数0.050,均匀度6.775,表明五指  相似文献   

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