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1.
近40年东北地区陆栖脊椎动物种群数量及其生境变化评估   总被引:1,自引:0,他引:1  
生物多样性是生态平衡维持和生态过程与功能实现的基础,东北地区是我国乃至全球生物多样性最为丰富的地区之一。为研究和探讨东北地区陆栖脊椎动物种群数量与生境变化之间的关系,利用物种调查数据和生境遥感观测数据,以地球生命力指数、生态系统面积和破碎度等指示性指标,综合评估了近40年东北地区陆栖脊椎动物种群数量及其生境变化。结果表明:1970—2010年,东北地区陆栖脊椎动物种群数量下降了近70.1%,森林脊椎动物种群数量减少了近80.9%,草原和荒漠生态系统脊椎动物种群数量增加了近180.9%。1980—2010年,湿地物种种群数量减少了近75.7%。1980—2015年期间,农业和城镇建设用地增幅分别达到25.2%和32.3%,不断挤占和蚕食着自然生态空间,致使自然生境面积不断减少,减幅约为8.0%。自然生境景观破碎化程度总体呈现加重趋势,尤其是森林生境,破碎化指数增加约42.7%。但是,2005年之后,自然生境景观破碎化程度加重趋势趋缓,与2005年之后脊椎动物种群数量减少幅度减缓趋势一致。森林砍伐、人口增长、城镇化、交通建设等造成的自然生态系统破碎度增加和栖息地质量下降对大型兽类影响比较显著。  相似文献   

2.
向海自然保护区丹顶鹤生境结构空间特征   总被引:9,自引:1,他引:8  
张艳红  邓伟  张树文 《生态学报》2006,26(11):3725-3731
丹顶鹤为国家一级保护珍稀禽类,是向海自然保护区重点保护对象。在我国乃至世界范围的丹顶鹤保护中占有重要的地位。近年来,由于自然条件和人类活动的干扰,丹顶鹤的天然家园.沼泽湿地发生退化,其生存受到威胁,丹顶鹤的数量波动变化较大。为了有效地保护丹顶鹤有必要详细了解和掌握其生境结构的空间特征和变化特点,以了解丹顶鹤的生境动态。在RS、GIS技术和统计分析方法的支持下,运用景观生态学方法对向海自然保护区丹顶鹤生境空间结构特征从景观特征、生境斑块空间关系和生境破碎化3个方面进行分析。选择景观斑块面积、周长、斑块大小以及斑块密度等描述保护区景观格局基本特征。利用斑块的邻接边界长度和斑块间隙指数分析丹顶鹤生境——沼泽斑块的空间邻接关系和聚集程度,数据表明沼泽斑块与人类活动频繁的耕地邻接较为紧密,而自身的间隙指数自20世纪70年代以来有明显增大趋势。分析了由于自然原因和人为活动影响所造成的丹顶鹤生境斑块的空间破碎化程度。计算结果表明,由于沼泽生境自身条件的限制,研究区内物理性破碎化减少的生境面积为2039.6hm^2,人为破碎化(居民地和道路)减少的生境面积为3845.1hm^2,这样研究区内丹顶鹤适宜生境面积为13680.1hm^2,可见人类活动对丹顶鹤生境影响很大。研究为保护区内丹顶鹤物种的保护和生境管理提供重要的科学依据。  相似文献   

3.
景观破碎化对东北虎主要猎物种群动态影响的模拟   总被引:2,自引:0,他引:2  
以完达山东部地区的现实景观为背景,采用空间直观种群模型LAPS和情景模拟相结合的"虚拟实验"途径,模拟了在10个不同破碎化程度的景观情景中东北虎的主要猎物于1992-2011年间的种群动态,评价了完达山东部地区当前的景观破碎化程度对东北虎主要猎物种群动态的影响。结果表明:LAPS模型准确刻画了研究区东北虎主要猎物种群数量急剧下降的趋势,2002年模拟的东北虎主要猎物的种群数量和实测值之间没有显著差异,马鹿、野猪和狍子的P值分别为0.8651、0.9534和0.2836;不同生境类型的种群密度数据与实测值之间均没有显著差异,其中阔叶林生境中的马鹿、野猪和狍子的P值分别为0.8521、0.9447和0.3152;在灌丛生境中的马鹿、野猪和狍子的P值分别为0.8846、0.9576和0.2415。斑块类型和景观水平上的格局指标变化趋势表明由于农田扩张导致10个景观情景的破碎化程度逐渐增加,景观水平的破碎化程度低于斑块类型水平。方差分析显示10个景观情景中的种群数量没有显著差异,马鹿、野猪和狍子的P值分别为0.8516、0.2624和0.7636,说明研究区当前的景观破碎化程度对种群动态影响并不显著。完达山东部地区存在盗猎等人为干扰,导致了东北虎主要猎物的数量远低于环境容纳量,景观破碎化虽然在局部地区较为严重,但完达山东部地区整体上景观破碎化并不强烈,该地区景观破碎化的效应尚未显现。认为控制盗猎等人为干扰是增加该地区东北虎主要猎物的数量、实现东北虎种群恢复所应优先采取的措施。  相似文献   

4.
区域农田景观格局对麦蚜种群数量的影响   总被引:2,自引:0,他引:2  
张永生  欧阳芳  门兴元  戈峰  袁哲明 《生态学报》2018,38(23):8652-8659
明确农田景观格局对麦田蚜虫种群的影响,是开展区域性害虫生态调控的重要理论依据之一。以区域性小麦种植区为研究对象,基于遥感影像与土地覆盖分类数据以及田间调查的蚜虫种群数据,计算景观格局指数,使用负二项分布的广义线性模型从农田景观、非作物生境景观和区域景观3个方面分析了区域农田景观格局对麦田蚜虫种群的影响。结果表明,蚜虫种群的数量与草地的平均斑块面积和最大斑块指数显著正相关,与县域的平均几何最邻近距离和面积加权平均斑块面积显著负相关,与耕地的面积加权平均斑块面积显著负相关,与耕地的斑块密度显著正相关。草地斑块面积的增大、区域景观与耕地的破碎化、区域景观的聚集会促进蚜虫种群数量的增加。使用草地的斑块面积和最大斑块指数、区域景观的平均几何最邻近距离可以预测蚜虫种群的发生量。非作物生境草地的斑块面积、耕地的破碎化、区域景观的空间分布及破碎化是影响麦田蚜虫种群发生的重要景观因素。  相似文献   

5.
重庆市武隆县和彭水县交界处白颊黑叶猴种群初步调查   总被引:6,自引:0,他引:6  
1998年4月至2001年12月,对重庆市武隆县和彭水县交界处的白颊黑叶猴种群进行了4次调查。结果表明,该交界处有4个黑叶猴家族群栖息,其中数量最多的1群曾达到17-18只个体,最少的1群为5只左右,目前调查统计到的个体总数量约40-45只。以常绿阔叶树为主的“斑块状”天然阔叶林地是黑叶猴栖息地生境的主要特征。影响武隆县和彭水县黑叶猴种群数量和分布区缩减的主要原因是:人类频繁活动、栖息地破碎化和生境条件的变化,很大可能还有生殖隔离的影响。  相似文献   

6.
黑叶猴是栖息于喀斯特石山地区的珍稀濒危灵长类动物,由于非法捕杀和栖息地丧失,种群数量急剧减少。2017年10-12月,我们采用样方法调查恩城国家级自然保护区及其周边地区黑叶猴的种群分布、数量及保护现状,分析其致危因素,为制定有效管理行动计划提供理论依据。本次调查共记录到黑叶猴夜宿地89处,其中有43处夜宿地下方有新鲜排泄物。结合本次调查和访问,确定黑叶猴的种群数量为18群100~105只,包括1只全白化黑叶猴成年雌性个体;其中11群分布在保护区内,7群分布在保护区外。猴群由3~12只个体组成。栖息地破碎化和退化是威胁恩城保护区黑叶猴种群生存的主要因素。  相似文献   

7.
福建旅游型海岛景观格局变化——以妈祖圣地湄洲岛为例   总被引:2,自引:1,他引:1  
在RS和GIS技术支持下,利用1993和2005年遥感资料,选取景观斑块数、多样性指数、均匀度、优势度、分维数、破碎度等反映景观空间格局的指数,对福建省旅游型海岛典型代表湄洲岛的景观格局变化进行了分析。结果表明:1993—2005年,湄洲岛总的景观斑块数明显增加;景观多样性指数虽略有减少,但整体较高;景观破碎化指数呈明显增加趋势;在各景观类型中,建设用地、林地、沙滩及裸岩3种与旅游业紧密相关的景观类型面积增加,破碎化程度提高,受人类干预的强度在加大;耕地、荒草地、坑塘水体、海滩景观斑块类型的面积减少、破碎化程度降低,受人类干预的强度在缩小。  相似文献   

8.
研究同一个物种在不同生境觅食对策的差异不仅有助于了解其行为和生态的可塑性,还有助于评价其对自然或人为干扰导致的生境质量的改变的适应能力,从而为物种的有效保护和管理提供科学依据。本文以广西弄岗国家级自然保护区和扶绥保护区的黑叶猴为研究对象,采用瞬时扫描取样法收集相关的食性数据,并结合贵州麻阳河国家级自然保护区黑叶猴的食性研究结果,比较分析黑叶猴食物组成的区域性差异以探讨黑叶猴对不同喀斯特石山生境的行为适应对策。结果表明:黑叶猴3个地理种群共采食77科、182属、259种植物,木本植物(包括乔木和灌木)是其最重要的食物来源。3个地理种群均表现出较高程度的叶食性,树叶分别占其食物组成的52.7%、63.9%和79.7%。然而,3个地理种群的食物组成却存在显著差异,种群间总的食物重叠指数仅为1.33%-7.43%,主要食物的重叠指数仅为0-13.51%。这些差异可能与栖息地中植被组成的差异有关。与弄岗和麻阳河黑叶猴相比,扶绥黑叶猴采食更多的嫩叶和灌木。人为干扰对栖息地植被结构的影响可能是导致上述差异的主要原因。我们认为黑叶猴不同地理种群食物组成的显著差异反映其觅食的灵活性以应对不同喀斯特石山生境。  相似文献   

9.
吉林省镇赉县近10年景观格局变化   总被引:4,自引:1,他引:3  
以吉林省镇赉县2000年、2005年、2009年三期TM遥感影像为信息源,在小尺度下通过RS解译,对GIS建立的空间数据模型叠加分析和景观特征指数计算,结合自然与人文要素,具体分析镇赉县土地利用景观格局的变化情况。分析结果表明:近10a间研究区景观斑块面积和斑块的数量发生明显变化,水体景观类型斑块数量呈现大幅度增加,研究区各景观面积动态度变化显著,耕地面积大幅度增加,而草地和未利用土地面积大幅度减少。研究区景观破碎化程度较低、景观分维数较小且变化不大、景观异质性低,景观较为完整,该地区生态表现出明显的脆弱性和易恢复性。自然环境的制约、人为活动的干扰、政策的导向等因素决定和影响了该地区景观格局的变化趋势。  相似文献   

10.
豹曾广泛分布于甘肃省的陇中、陇东和陇南各地,但历史上大部分有豹分布地区的生境现已明显地不再适宜豹的生存。依据访问调查得到的信息并结合实地考察生境进行综合判断,目前豹存在可能性较大的地区有平凉地区的关山林业总场、张家川县马鹿林场、小陇山林业局张家林场和白水江国家级自然保护区。甘肃省豹濒危的主要原因是栖息地面积退缩,栖息地环境质量恶化,生境破碎化和人为猎捕。鉴于现阶段尚未查清豹的野生种群数量,应对豹及其猎物资源进行野外监测,采取积极有效的措施加强豹栖息地的保护与恢复。  相似文献   

11.
李友邦  陆施毅  苏丽 《生态学报》2015,35(7):2360-2365
动物使用生境中食物种类的方式对其适应性有重要的影响。为了研究黑叶猴在破碎化栖息地中利用食物的方式,2006年1—12月,采用焦点动物取样法和连续记录技术于每月初连续观察8 d,记录破碎化栖息地中黑叶猴取食的种类和时间,分析其食物多样性和月份间种类的重叠度。结果表明,黑叶猴年均食物多样性指数为3.03(范围1.93—2.62),且多样性指数在各月间没有显著的差异(One-sample K-S Test,P=0.99),说明黑叶猴在各月份中取食的食物种数相似,不同季节利用食物种数的变异程度不大。在所有的食物种类中,仅两种食物青檀Pteroceltis tatarinowii和潺槁树Litsea glutinosa在12个月份都被取食,其他种类则表现了月份间明显的季节性替代。各月份间食物种类的相似性在0.42(3—4月)和0.75(9—10月)之间变化。黑叶猴对破碎化生境中食物种类的利用方式是:首先利用常年均有的食物种类以保证食物来源稳定,同时选择性地利用新出现的种类,使食物种类多样化,满足不同的营养需求。  相似文献   

12.
We investigated the diet of a group of François' langur inhabiting a forest fragment between August 2002 and July 2003 to add to our knowledge of behavior and ecology of this langur. Our objective was to study whether the François' langur would adopt a feeding strategy similar to the white‐headed langur in the same nature reserve. Data indicated that a total of 37 plant species were eaten by François' langur; however, only ten species accounted for 90% of the total feeding time. Four species belong to the ten most dominant tree species within the vegetation quadrats. Ninety‐four percent of feeding time of François' langur was spent on leaves, whereas the remaining 6% of time was spent on fruits, flowers and twigs. Results also demonstrated that François' langur are similar to white‐headed langur in being predominantly folivorous and that Francois' langur adopted a similar strategy to white‐headed langur in diet, dietary variation and time spent on feeding. François' langur exhibited a habitat use preference for the middle zone of the forest, whereas the white‐headed langur utilized the bottom zone of the forest. Further analysis indicates that human interference and habitat fragmentation caused by agriculture also impact habitat use. Am. J. Primatol. 70:320–326, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

13.
Previous studies of Trachypithecus species indicated that they were selective feeders that concentrated on relatively few food species/items. From January to December 2005, I quantified potential food availability and the food species/items eaten by five groups of François' langur (Trachypithecus francoisi) in the Mayanghe Nature Reserve (MNR), People's Republic of China. These langurs fed on 164 species, of which the top ten accounted for 51% of all feeding records. Langurs consumed more species (91) in the spring than in other seasons (73 summer, 75 autumn, and 67 winter), and only 38 species were consumed in all seasons. Nontree food species, such as bushes and lianas, accounted for 47% of the total feeding records and for a majority (68%) of the feeding records in winter. The annual diet consisted of leaves (64% of feeding records), fruit and seed (32%), and other nonfoliage items (4%); the langurs switched from being more folivorous in spring (93%) and summer (79%) to being more frugivorous in autumn (53%) and winter (56%). There was no correlation between the proportion of feeding records and the food availability in the most frequently consumed species, indicating that these langurs were selective feeders; there were significant correlations between consumption and abundance in both the entire set of 112 food species and the set of 86 infrequently consumed species, indicating that foods that are more available are eaten more frequently. It appeared that in the seasonal and disturbed habitat, feeding decisions and diet composition of the langur may be driven more by food availability, and less by animal's selectivity, than at other sites. The results indicate that François' langur copes with habitat alterations by broaden its dietary breadth; this has implications for the adaptive significance of dietary breadth, and has implications for future conservation strategies for species which exist in degraded habitats. Am. J. Primatol. 73:1176–1187, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

14.
We carried out a study of Hanuman langurs in Sariska Tiger Reserve, Rajasthan, India during three months in 1990. The area surveyed included habitat disturbed by human activity, with both the grazing of livestock and firewood collecting resulting in degraded forest. Langur population density was estimated to be between 19 and 36 animals/km2. The density of langurs in disturbed areas was significantly lower than in undisturbed areas. Both tree cover, total tree, and shrub cover were positively correlated with langur density, suggesting that a lack of trees in disturbed areas may have caused the lower langur densities. Although bisexual groups were significantly more common in undisturbed areas the distribution of all male groups did not appear to be affected by human disturbance, suggesting that male bands are likely to inhabit more disturbed habitats than bisexual groups. We suggest that either a lack of food trees or the high density of predators in Sariska may prevent bisexual groups from inhabiting areas where tree cover is low, although the more mobile male groups can survive in these areas. Although Hanuman langurs are a relatively common species in India, these results suggest that they are not, as is commonly assumed, immune to the effects of human disturbance. In areas where langurs appear to survive in disturbed habitats the different response of bisexual and all male groups to disturbance may still result in serious disruption to the population structure.  相似文献   

15.
Comparative studies of the diet of the same species in different habitats, and over the long term, are essential to understanding a species’ behavioral and ecological plasticity. Moreover, such studies can help researchers and managers evaluate a species’ capacity to cope with changes in habitat quality resulting from natural processes or human disturbance, which is important for developing conservation strategies. We compared dietary data for François’ langur (Trachypithecus francoisi) collected at Nonggang and Fusui Nature Reserves, Guangxi Province, China, over 2 separate study periods to evaluate interannual and intersite variation in diet. Young leaves were the preferred staple foods for langurs, whereas mature leaves and seeds served as fallback foods in response to seasonal shortage in the abundance of young leaves. Species composition of the diets and the percentage of feeding records for plant species varied between the 2 study periods. The langurs at both study sites fed selectively, and they did not base their diet simply on the abundance of plant species in the habitat. However, the plant species eaten by langur groups inhabiting the 2 different reserves were markedly different, and the top 10 food species eaten by the Fusui group showed no overlap with those eaten by the Nonggang group. The variation may be related to differences in forest composition resulting from different level of human disturbance. In summary, our results indicate that François’ langurs exhibit a comparable dietary pattern both temporally and geographically, but there is marked interannual and intersite difference in species composition of the langur diet.  相似文献   

16.
喀斯特石山是一类特殊环境,生存在喀斯特石山的动物形成特殊的行为机制以适应这一特殊的环境.石山叶猴是仅分布于喀斯特石山地区的珍稀濒危灵长类动物,属疣猴亚科乌叶猴属的一个种组,包括黑叶猴(Trachypithecus francoisi)、白头叶猴(T.leucocephalus)、德氏叶猴(T.delacouri)、金头...  相似文献   

17.
We studied the socioecology of white-headed langurs (Trachypithecus leucocephalus) from September 1997 to September 1998 in Fusui Precious Animal Reserve, SW Guangxi, China. We collected data on climate, phenology of food plant species, and foods consumed by langurs living in habitats with different levels of human disturbance. Feeding records showed that the most food is from less common plant species. Young leaves were the staple food item in all langur groups, and consumption correlates with availability. Consumption of mature leaves is not significantly correlated with their availability, but the langurs fed on them, and other food items such as fruits and seeds, when the availability of young leaves was low. Langurs in different areas had broadly similar diets, but they varied most in the proportion of supplementary items such as fruit. Groups in more disturbed habitat did not increase the overall proportion of mature leaves in their diet, but instead maintained their intake of young leaves from a greater diversity of species, and incorporated more immature fruit. Conservationists should direct efforts toward protection of rare plant species providing preferred food items, particularly supplementary foods at times when, and in areas where, preferred food items are less available.  相似文献   

18.
This paper discusses the taxonomy and distribution ofPresbytis francoisi. We are especially concerned with the classification of the white-headed langur.T'an (1957) suggested that the white-headed langur be classified as a separate species,Presbytis leucocephalus. We suggest that the white-headed langur is a subspecies ofPresbytis francoisi and should be referred to asP. francoisi leucocephalus. The distribution of the six subspecies of the françois' langur,P. f. delacouri, P. f. francoisi, P. f. hatinhensis, P. f. laotum, P. f. leucocephalus, andP. f. poliocephalus, is limited to southeastern Asia.  相似文献   

19.
开展近缘物种觅食行为比较对理解动物的行为可塑性及适应性具有重要意义。白头叶猴(Trachypithecus leucocephalus)和黑叶猴(T.francoisi)是近缘物种,体形大小相近,社会结构和栖息环境相似,是广西崇左白头叶猴国家级自然保护区喀斯特季节性雨林中邻域分布的灵长类。为了探索两个物种在喀斯特生境中是否有相似的觅食策略,我们于2012年1-12月采用瞬时扫描取样法对两种叶猴的觅食行为进行研究。结果表明,白头叶猴与黑叶猴在不同时段均为叶食性,树叶是两种叶猴各个时段主要食物,其中白头叶猴日均取食树叶77.0%±4.4%,黑叶猴日均取食68.9%±8.3%,两者对树叶的采食比例均没有显著的日时段差异(白头叶猴:χ2=6.602,df=11,P=0.830;黑叶猴:χ2=11.393,df=11,P=0.411)。两种叶猴的觅食行为都在猴群清晨离开夜宿石洞后和进入过夜山洞前的时段中频繁发生。白头叶猴在09:00-10:59和16:00-17:59出现觅食高峰,时间占比分别为41.7%和46.3%;黑叶猴同样在09:00-10:59和16:00-17:59的时间段内发生高频率的觅食行为,时间占比分别为31.3%和38.0%。此外,两种叶猴的觅食时间在大部分时段中的差异并不明显。白头叶猴和黑叶猴在石灰岩生境中具有相似的觅食策略,这意味着两种叶猴在取食生态学上可能采取相似的保护措施。  相似文献   

20.
The six limestone langur taxa of Southeast Asia inhabit the rugged limestone karst mountains, although the reason for their current restriction to this habitat is unclear. From August 2007 to July 2008, I collected data on the diet and feeding behavior of the critically endangered Delacour's langur (Trachypithecus delacouri) in Van Long Nature Reserve, Vietnam. I used these data to evaluate the hypothesis that limestone langurs are found on karst habitat because they depend on endemic limestone plants. Feeding accounted for 29% of the langurs' activity budget. Young leaves dominated the diet monthly, seasonally, and annually. The annual diet consists of nearly 79% foliage with almost 60% young leaves. Despite a distinct wet and dry season, over the study period, seasonal variation in plant part consumption was slight. Fruit and seeds were a small contribution to the diet. Delacour's langurs ate 42 of 145 available species, and they concentrated on a subset of this number. Five plant species comprised more than 60% of the diet and 16 species comprised more than 93%. More than half of the diet came from climbers. Delacour's langurs are among the most highly folivorous of studied colobines and, along with the closely related T. leucocephalus of southern China, the most folivorous of the Asian langurs. Whether high folivory is owing to a lack of available fruits and seeds in limestone habitats is unknown. What is certain, however, is that the plant species most important in the Delacour's langurs' diet at VLNR, throughout the study, were not plants endemic to limestone. Feeding dependence alone, therefore, cannot explain the current distribution of limestone langurs on karst habitat. Am. J. Primatol. 72:317–324, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

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