89 resultados para Bai Shuihe Nature Reserve

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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对白水河自然保护区进行了生物多样性和植物区系调查,根据获得的生物多样性数据和标本的鉴定结果分析,得到结果和推论如下:1.白水河自然保护区生物多样性的垂直分布格局1.1 植物群落α 多样性随海拔梯度的变化乔木种的丰富度及多样性随海拔上升表现出明显的线性下降趋势。而灌木和草本物种丰富度及多样性随海拔上升表现出抛物线式的下降趋势。乔木种从海拔1400m 的15 种至林线时下降为2 种;灌木和草本植物分别从35 和38 种至山顶时下降为5 种和20 种。乔木物种随海拔升高出现明显的物种替代现象,表明海拔梯度包含了多种环境因子的梯度效应,影响着植物群落的分布与结构及物种多样性。1.2 植物群落β 多样性随海拔梯度的变化海拔2200 m 左右是一个明显的生境转折点。海拔2200 米以下相邻群落的相似性( CJ ) 明显大于海拔2200 m 以上的群落,说明海拔2200 m 以下的群落间共有种多,生境差异较小;而海拔2200 以上的群落则相反,相似性较低。低海拔区由于人为干扰较大,所以群落具有较高的物种丰富度,相邻群落之间的物种替换总量(Cody 指数) 较大。海拔2800 米到海拔3200 米之间因杜鹃群落的影响,物种替换总量(Cody 指数) 略有升高。研究β 多样性沿海拔梯度的变化必须考虑到物种丰富度和群落类型的影响,用不同指数从不同角度能更好地理解β 多样性沿环境梯度的变化。2.白水河自然保护区植物区系性质及起源白水河自然保护区自产种子植物计138 科421 属990 种。本文在科、属的水平上对该保护区植物区系特性进行了较深入的统计和分析。统计表明,温带和热带分布型均占有相当比重,但温带分布型稍占优势;热带、亚热带和温带的科、属多,中国特有属也有相当比例,它们是保护区具有特征意义的类群,其中许多属为古老和残遗成分。结论认为白水河保护区植物区系起源古老,较完好的保存了北极-第三纪古植物群。We have collected the specimens and gotten the biodiversity datas of BaiShuihe Nature Reserve in Peng Zhou,analysed the datas,the results as follows:1. Diversity of the plant community along altitudinal gradient1.1 α diversity of the plant communities along altitudinal gradientFrom 1400m to 3900m at Baishuihe Nature Reserve, 52 plots were investigatedwith an interval 100m in altitude; α diversity and β diversity of plant communitiesand their variety along altitudinal gradient were studied. The results showed that indifferent successional layers of trees, richness and diversity decreased linearly withthe increase of altitude. But shrub and herb layers don’t decrease linearly with theincrease of altitude. Tree species decreased from 15 species at 1400m so only 2species at timberline. Shrub and herb species decreased from 35 and 38 species at2000m to 5 and 20 species at 3800m respectively. Tree species are replacedobviously with the increase of altitude; It shows that altitude includes manyenvironmental facts, which infect the distribution, structure and diversity of plant population.1.2 The variety of βdiversity along altitudinal gradient.The entironment changed obviously near 2200m according to our research. Forsimilarity(CJ) between neighboring plots above 2200m is larger than wich below it.It shows that below 2200m,the neighboring plots has more same species,and thehabitats of neighboring plots has more similarity. Above 2200 is the other way round.The plant communites have higher species richness and species turnoverlargestly between neighboring plots because of the disturbance from humanity at lowaltitude. Between 2800m and 3200m species turnover not so obviously because ofmore Rhododendron live there.We should think over species and the types of plant communities effect thevariety of β diversity along altitude gradient. Use more biodiversity indexs and fromseveral aspects to understand the variety of β diversity along altitudinal gradient.2.Origin and characteristic features of Bai Shuihe Nature Reserve990 species of wild seed plants (belonging to 421 generas in 138 families) inthe floristic region of Bai Shuihe Nature Reserve were reported here. The statisticsand comparatively intensive analysis at generic and familiar levelss. Based on thestatistics,the results show that both temperate and tropical distribution types areacounted for considerable proportion of the total,but formal is a little moreimportant than the later. The North Temperate and E.Asia-N.America disjunctedpatterns are more concentrated in this area. These may be considered as thecharacteristic features of Bai Shuihe Nature Reserve flora, while many of them arearchaic and relic elements. According to above data,the floristic region of BaiShuihe Nature Reserve may be considered as a typical region in Chinese flora. Also,the flora of Bai Shuihe Nature Reserve are originated since ancient time as a wellconserved Arctic-Tertiar flora.

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Ecological survey of macrozoobenthos assemblages was carried out at 32 sites in the East Dongting Nature Reserve, located in the northern region of the East Dongting Lake in the middle basin of the Yangtze River, China. All total 51 taxa including 18 oligochaetes, 15 mollusks, 14 insects and four other animals were recorded. Mollusks composed the dominant group and accounted for more than 70% of the total abundance. Assemblages were composed mainly of scrapers (66.7%) and collector-gatherers (nearly 20%), and to a lesser extent collector-filterers (roughly 12%), predators (ca. 7%), and shredders (ca. 6%). Two-way indicator species analysis, detrended correspondence, and canonical correspondence analysis (CCA) were employed to identify the relationships between macrozoobenthos assemblages and environmental variables. Thirty-two sites were separated into four site groups based on composition and relative abundance of benthic macroinvertebrates. CCA detected that water depth, pH, conductivity, SiO2, total nitrogen, total phosphorus, alkalinity, hardness, and Ca2+, were significant environmental factors influencing the pattern of macozoobenthos. In this minimal subset, water depth, pH, alkalinity and hardness were the most influential variables.

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Several methods for estimating the potential impacts caused by multiple probabilistic risks have been suggested. These existing methods mostly rely on the weight sum algorithm to address the need for integrated risk assessment. This paper develops a nonlinear model to perform such an assessment. The joint probability algorithm has been applied to the model development. An application of the developed model in South five-island of Changdao National Nature Reserve, China, combining remote sensing data and a GIS technique, provides a reasonable risk assessment. Based on the case study, we discuss the feasibility of the model. We propose that the model has the potential for use in identifying the regional primary stressor, investigating the most vulnerable habitat, and assessing the integrated impact of multiple stressors. (C) 2006 Elsevier Ltd. All rights reserved.

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Chang-Fu Wang, Xian-Qiu Ren, and Run-Lin Xu (2010) Composition, abundance, and diversity of the Peracarida on different vegetation types in the Qi'ao-Dan'gan Island Mangrove Nature Reserve on Qi'ao Island in the Pearl River estuary, China. Zoological Studies 49(5): 608-615. Almost nothing is known about the Peracarida in the Pearl River estuary. This is the 1st report to study the composition, abundance, and diversity of the Peracarida in the Qi'ao-Dan'gan I. Mangrove Nature Reserve on Qi'ao I., in the Pearl River estuary, southern China. Bimonthly samplings were carried out in 3 representative vegetation types (mangrove arbor, emergent plants, and seaweed) for 2 yr. Using a Peterson grab, 1940 individuals (id.) were collected in total, including 11 species of 6 genera, 5 families, and 3 orders (Amphipoda, Isopoda, and Tanaidacean). Discapseudes mackiei Bamber 1997 was the dominant species with the highest density of 1,432 incl./m(2). The effect of temperature on the abundance of Peracarida was significant (p < 0.01), and the optimum temperature was 22-23 degrees C in both the mangrove arbor and seaweed. The results showed that the abundance of the Peracarida was higher in the mangrove arbor, while the diversity, especially Amphipoda diversity, was higher in the seaweed. In contrast, emergent plants provided no suitable habitats for the Peracarida. http://zoolstud.sinica.edu.tw/Journals/49.5/608.pdf

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Elevational and latitudinal patterns of species richness for birds and mammals were compared with human population density in relation to nature reserve designation in two areas of Yunnan Province, China. Results suggest that species richness is not the same for the two areas. In Gaoligongshan Region, species richness is inversely correlated with elevation and altitude, while reserve designation is positively correlated with elevation and latitude. In Jingdong County, reserve designations are positively correlated with elevation, but species richness shows no clear trends. In general, the present situation is strongly influenced by human activities. It appears that reserve designation is mismatched with species richness in Gaoligongshan Region, while there is a better fit between the two in Jingdong County. In both areas, however, it appeared that reserves were located primarily in order to reduce conflict with humans rather than to maximize conservation of biodiversity, probably because humans were responsible for forest-especially primary forest-destruction and degradation in the low-lying areas.

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Ministry of Science and Technology of China [2008BAK47B02, 2008BAC44B04, 2008BAK50B06, 2008BAC43B01, 2006BAC08B06]

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保护区是否真的能起保护作用?保护区究竟如何布局?这是自然保护区的建设一直争论不休的课题。就大熊猫保护而言,目前面临的最紧迫问题可能不是保护区数量多少的问题,而是这些多个保护区组成的保护区群的配置或格局是否合理。因此,本研究以岷山大熊猫保护区群为研究对象,分析现有大熊猫及栖息地及其保护现状,指出目前保护区存在的问题,并对岷山大熊猫自然保护区群合理布局提出建议性设计,以期为大熊猫保护及自然保护区建设的理论提供借鉴。 到目前,为了保护大熊猫,在岷山地区已经建立了1 7个自然保护区,这些保护区的建立对大熊猫的保护起到了非常重要的重要。但是,大熊猫栖息地仍然持续下降。就其原因有两方面,即岷山地区人为活动的干扰,如旅游业的盲目发展。但,同时大熊猫自然保护区本身的布局存在一定的不合理性。最后,从景观尺度上提出岷山大熊猫保护区群合理建设的布局,即在分析现有保护布局基础上,找到优先保护的敏感地带建立廊道,将所有保护区连成布局合理的保护区群。 大熊猫受威胁的关键因子并不是竹子,而是森林.竹子复合系统的破碎化或质量的退化,故保护大熊猫应从保护森林、恢复森林.竹子复合生态系统的质量入手。但是,具体实践中究竞采取什么模式来恢复退化的大熊猫栖息地?选取不同模式的科学依据是什么?如何评判不同恢复模式的成本和效益?这些方面的工作到目前缺少系统研究。本研究在分析了岷山地区自然、社会与经济条件的基础上,从荒山荒地造林、天然林保护与低效林地改造主要植被恢复措施着手,全面分析各类植被恢复措施所形成植被的生态效益(保持水土、涵养水源、保持肥力等)、经济收益(木材、果品和林副特产品)、社会效益(种植结构、劳动力再分配等),总结出植被恢复成本和效益的构成要素,计算主要植被恢复模式的成本和效益,为选择适宜的植被恢复措施、典型植被恢复模式和合理确定植被恢复技术提供科学依据,从而推动岷山植被快速健康地恢复,为大熊猫提供适宜的生存空间。 三峡大坝的建设使其固有水域的人为改造导致水位上升,使原本连续的山地生态系统被分割成大小不等的岛屿。水位变化导致的这种生境岛屿化为栖息地破碎化和岛屿生物地理学提供了十分难得的实证研究的机会。然而,同时,这种栖息地的片段化无疑对三峡库区生物多样性保护和生态系统的完整性造成威胁。到目前,为了监测库区建设对生态环境的影响,已经建立了22个定位观测站,但没有一个是生境破碎化方面的,为此建议尽快建立生境破碎化方面的定位研究站。三峡库区生物多样性丰富,但保护区面积仅仅占库区面积的6.9%,而同期我国已经建立了1 999个自然保护区,占国土面积的15%,因此,非常迫切建立更多的保护区(至少达到全国平均水平)。为了从宏观尺度上加强对库区的综合保护,建议从景观生态学的角度出发,将库区作为一个自然、社会和经济复合生态系绕对待。

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本文从种群、群落、景观等水平研究了浑善达克沙地退化状况,发现浑善达克沙地生态系统退化严重。运用“以地养地”模式,建立自然保护地,能恢复浑善达克退化生态系统,同时能实现社区的经济发展。通过对自然保护区恢复潜力和可行性的分析,发现将“以地养地”模式推广到全旗,可实现全旗的可持续发展。运用自然保护区设计理论,对拟建自然保护区进行了设计,并对自然保护区-社区的区域可持续发展能力进行了分析,提出了可持续发展战略。有以下主要内容: 1)浑善达克沙地榆树疏林种群在人为干扰下处于衰退期。本研究表明,浑善达克沙地中部榆树疏林种群是一个数量处于下降的种群。中老龄龄级榆树较多,而年幼龄级榆树较少。种群静态生命表表明,幼苗库严重不足,种群进入中老龄期后,外界干扰(例如直接砍伐等)导致了个体较高的死亡量。按照一次平均推移法预测各龄级在未来20年、40年、60年及100年后的株数,老龄龄级株数将有所增加,而中幼年株数则下降。目前蓝旗榆种群中老年个体仍保持着比较旺盛生殖能力,应该充分利用这一特征,采取适度放牧、严禁超载过牧、严禁滥砍滥伐等措施,促进天然更新。 2)浑善达克沙地沙丘植物群落退化严重。浑善达克沙地中部典型固定沙丘调查表明,阴坡植物群落种类复杂,主要为耐阴乔木半乔木+灌木+柳灌丛类,群落较为稳定。阳坡主要以褐沙蒿、雾冰藜和虫实为主,种类组成较为简单,沙脊为沙蒿+半旱生杂草类,腰地形成木岩黄芪+半灌木半旱生杂草类。落沙地形成虫实+狗尾草优势群落,风蚀坑形成狗尾草+虫实+褐沙蒿优势群落。顶部则形成虫实单优势群落。固定沙丘退化严重,有活化的可能,需要加强保护,控制放牧强度。 3)浑善达克沙地榆树疏林在景观水平上破碎化严重。研究发现榆树疏林斑块在全旗分布不均匀,斑块集中分布于北部苏木。其中有20个嘎查所含疏林斑块面积较多,占该旗疏林斑块总面积的86%,是主要分布区。榆树疏林斑块密度较低,斑块边界割裂严重,斑块之间分离度高,大斑块较少,小斑块数量多。 4)建立保护区可恢复浑善达克退化生态系统。运用以地养地模式,将大部分退化沙地围封保护,进行自然恢复;在小面积土地上建立了高产高效饲料基地,以向上一营养级提供足够的能量。结果表明,牲畜的压力逐步向小范围的土地集中,而大面积的退化草地借助自然力逐步恢复。群落生物量、平均高度和总盖度2年后均显著增加。植被组成方面,优质牧草比例提高。生态恢复不仅使自然生态系统得以恢复,而且带动了社会经济的发展,项目中的正蓝旗巴音胡舒嘎查牧民,在实验示范以后,年人均收入提高了32%。在全旗自然保护区建成后,大量居民将从保护区内迁移到城镇中去,有利于提高城市化水平,有利于调整产业结构,对于当前逐渐发展的二、三产业有促进作用;同时,自然保护区面积扩大有利于城市人口增长,能为城市发展提供消费食物来源、水源保障、环境保障。 5)拟建自然保护区设计。按照景观规划理论、Diamond自然保护区设计原则,选择榆树疏林斑块集中分布区,作为潜在核心区,运用ArcGIS的缓冲区分析功能,设计不同的宽度。同时调查斑块外不同距离样方与疏林斑块的群落相似度。由此而初步确定的核心区分布在正蓝旗23个嘎查,面积1 531 km2,约占全旗总面积的15%。根据核心区边界的生态、经济社会发展等因素,以及保护核心区所需要的最小宽度、当地土地利用所能规划的最大宽度,确定了不同区域的缓冲区宽度。由此而确定的缓冲区面积为1140km2,占保护区总面积的11.2%。其他地区均设置为过渡区,面积为7514km2,占保护区总面积的73.8%。 6)浑善达克自然保护区-社区的可持续发展。按照区域可持续发展理论,对浑善达克自然保护区-社区的各个苏木、镇、牧场、示范区,按照环境、经济、社会三个子系统进行了综合评价。发现可以按照区域可持续发展原则将正蓝旗划分为四个区域、两条畜产品产业带,简称“四区两带”战略:北部景观保护区、西部生态功能恢复区,以自然保护和生态恢复为主;中部社会经济服务区,以经济社会发展为主,集中建设好三个小城镇,发展集约化畜牧业、生态旅游产业;南部低山丘陵农业区,以及沿国道、省道的畜产品产业带。

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长白山自然保护区始建于1960年,位于北坡的红松针阔叶混交林森林生态系统是我国东北地区典型温带地带性森林植被之一,面临着全球气候变化和人类干扰的双重影响。 本研究以间隔43年的野外调查数据为基础,对1963年和2006年的长白山自然保护区北坡海拔800~1700m的森林植物群落进行对比分析,得到该区域的森林结构、植物多样性与碳储量的变化特点,讨论森林动态变化与人类活动、气候变化的关系,评价长白山自然保护区的保护效果: 对长白山北坡森林沿海拔梯度的森林结构和植物多样性的分析表明:群落的整体空间格局保存完好,植物种类变化不大,乔木层的建群种的种类基本不变,植物多样性与海拔高度呈负相关关系;林下层植物多样性受小环境影响,与海拔高度无明显相关。 以红松(Pinus koraiensis)针阔混交林、红松针叶混交林和云冷杉暗针叶林三种类型为单元分别研究各森林类型的多样性变化:α多样测度选择物种丰富度、Shannon-Wiener和Pielou均匀度指数,较好体现了样地内发生的多样性变化,灌木层和草本层多样性明显下降,一些稀有种和药用物种消失,红松等原优势物种有衰退趋势,阔叶树比例增大;β多样性测度选取Cody指数,体现出海拔梯度上的植被空间格局细节变化,演替层特别是阔叶树的物种更替变化有向高海拔移动的趋势。 对森林生态系统各层次碳储量进行估算:乔木层和灌木层采用维量法,对灌木层自建生长回归方程;草本层、枯枝落叶层采取收获法;植物细根采取根钻法;土壤采取土壤深度加权法。碳密度估算结果都与前人研究结果相似。各类型植被碳库总碳密度都达到170 t/hm2,远远高于国内平均森林植被碳库密度值44.9 t/hm2。 乔木层43年来的碳储量变化都无显著性差异,但仍表现出:阔叶树种碳储量上升,特别在高海拔类型这种变化更加明显;针叶树种碳储量在暗针叶林内大幅下降;树干的碳库分配比例都有所减少,表明植被碳库正存在向不稳定性方向发展的趋势。针阔混交林和暗针叶林的土壤碳储量,与植被碳库出现相反的变化趋势,整体碳库保持在一个相对平衡的状态。 推测造成这种变化的原因是:禁止砍伐等保护措施的实施,基本保存了乔木层垂直分布格局,而气候变暖使阔叶树种比例大幅增加,采集松籽等人类生产及旅游活动对林下层植被影响破坏较大。提议加强保护区内管理力度和规划,以减缓长白山北坡森林群落的不稳定变化趋势。

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The Hainan gibbon (Nomascus hainanus) is one of the most endangered primates in the world, confined to mature natural forest in Hainan Island, China. We assessed changes in habitat condition on the island between 1991 and 2008, using vegetation maps generated by remote-sensing images. We defined forest suitable for gibbons based on composition, tree size and canopy cover. During the 17-year period, the area of suitable gibbon forest decreased by 540 km(2) (35%) across the whole island, and by 6.3 km(2) (7%) in the locality of the sole remaining gibbon population at Bawangling National Nature Reserve. The forest patches large enough (>1 km(2)) to support a gibbon group decreased from 754 km(2) to 316 km(2) in total area, and from 92 to 64 in number. Suitable natural forest was mainly replaced by plantations below 760 m, or degraded by logging, grazing and planting of pines above 760 m. Meanwhile, forests in former confirmed gibbon areas became more fragmented: mean area of patches decreased by 53%. We mapped the patches of natural forest in good condition which could potentially support gibbons. We recommend a freeze on further expansion of plantations between core patches at Bawangling, Jiaxi-Houmiling and Yinggeling Nature Reserves in accordance with forest protection regulations; establishment of nature reserves in currently unprotected natural forest patches elsewhere in line with the local government's nature reserve expansion policy; and active natural-forest restoration between remaining fragments at Bawangling. (C) 2010 Elsevier Ltd. All rights reserved.

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Specific interactions among biomolecules drive virtually all cellular functions and underlie phenotypic complexity and diversity. Biomolecules are not isolated particles, but are elements of integrated interaction networks, and play their roles through specific interactions. Simultaneous emergence or loss of multiple interacting partners is unlikely. If one of the interacting partners is lost, then what are the evolutionary consequences for the retained partner? Taking advantages of the availability of the large number of mammalian genome sequences and knowledge of phylogenetic relationships of the species, we examined the evolutionary fate of the motilin (MLN) hormone gene, after the pseudogenization of its specific receptor, MLN receptor (MLNR), on the rodent lineage. We speculate that the MLNR gene became a pseudogene before the divergence of the squirrel and other rodents about 75 mya. The evolutionary consequences for the MLN gene were diverse. While an intact open reading frame for the MLN gene, which appears functional, was preserved in the kangaroo rat, the MLN gene became inactivated independently on the lineages leading to the guinea pig and the common ancestor of the mouse and rat. Gain and loss of specific interactions among biomolecules through the birth and death of genes for biomolecules point to a general evolutionary dynamic: gene birth and death are widespread phenomena in genome evolution, at the genetic level; thus, once mutations arise, a stepwise process of elaboration and optimization ensues, which gradually integrates and orders mutations into a coherent pattern.

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下载PDF阅读器2004年10月-2005年5月,在云南纳帕海自然保护区采用定点扫描法对越冬黑颈鹤(Grus nigricollis)的集群类犁和集群大小进行了观察.结果表明黑颈鹤夜间集群夜栖,形成较大的夜栖群,平均群体大小为67.9只(16-157,n=17):按照有无灰鹤加入,又将其分为同种集群和混种集群两种类型,其中同种集群的黑颈鹤数量占整个越冬种群的65.3%.在白昼,黑颈鹤以家庭鹤、集群鹤及特殊群体3种类型活动,家庭鹤和集群鹤的平均大小分别为2.7只(2-4,n=145)和16.1只(3-65,n=1017).黑颈鹤的集群大小并不稳定,在日内和月份间均有明显变化(P=0.000<0.05).存越冬期,最大集群形成于12月,其次为11月和1月;在日内,早上8时集群最大,随后减小并保持相对稳定,18时黑颈鹤开始向夜栖地靠拢,使得集群再次开始增大.随后观察中还发现,黑颈鹤的家庭解体过程开始于3月底,当幼鹤被成鹤驱逐离群后,逐渐加入集群鹤活动,从而使得家庭鹤和集群鹤的大小和组成发生改变.黑颈鹤的集群大小和组成受自身状况、种内关系、天气、食物等多种因素的共同影响,随时间和季节变动而发生变化,是对自身、种群和环境条件变化的综合反映.