三江自然保护区丹顶鹤春季觅食生境初步研究

采用样方因子测定法对三江国家级自然保护区丹顶鹤春季觅食生境进行调查研究的结果表明:丹顶鹤春季主要在以苔草、小叶章为主的沼泽湿地中觅食;觅食地植被高度小于40 cm,植被密度低于400株/m2,植被盖度为0～25%,觅食地水深多为5～15 cm,人类干扰距离大于1 500m;人为活动严重影响着丹顶鹤的觅食;春季丹项鹤有在...     

钳嘴鹳迁徙途经西双版纳期间觅食生境选择初探

钳嘴鹤迁徙期觅食生境选择研究在国内还未见报道，2012年5月31日至9月13日多次对迁徙途径西双版纳的钳嘴鹳觅食生境选择情况进行调查。结果发现，钳嘴鹳觅食生境选择的主因子是人为干扰、水、食物、隐蔽物，最适觅食生境是无人类干扰的、植被覆盖率较低的、有相对稳定食物的浅水湿地。     

重庆金佛山黑叶猴的春季生境选择

2007年3—5月,在金佛山自然保护区调查黑叶猴对生境的选择和利用情况,采用资源选择函数和资源选择指数进行分析,结果表明:影响黑叶猴生境选择的关键因子是上层乔木郁闭度、灌木胸径、人为干扰、洞穴距离。黑叶猴喜欢在郁闭度大于0.5、乔木和灌木密度大于21棵.(400 m2)-1、灌木胸径大于8 cm、人为干扰大于1 000 m、洞穴距离小于500 m、水源距离小于250 m、南坡的乔木-灌木混交林活动。黑叶猴的生境资源选择函数为:logit(P)=-21.964+2.126×DBH+2.108×CA+2.081×HD-1.829×DC(DBH为灌木胸径,CA为上层乔木郁闭度,HD为人为干扰距离,DC为洞穴距离)。黑叶猴对生境的选择概率为:P=elogit(P)/(1+elogit(P))。     

辽宁朝阳越冬大天鹅种群与栖息地调查

朝阳是大天鹅迁徙路线上的重要停歇地,每年途经朝阳停歇的大天鹅超万只。近些年监测到一些大天鹅种群选择在朝阳越冬,不再向南迁徙。针对这一现象,于2017-2019年连续3 a 1月份采取直接计数法实地调查大天鹅越冬地的大天鹅数量和自然环境,并从气候、环境、食物、人为干扰因素、保护力度等方面分析大天鹅改变原有迁徙习性的原因。     

青海湖非越冬水鸟多样性分析

于2006年4-9月,在不同的迁徙阶段首次在青海湖15个重要的繁殖地和迁徙停歇地,对水鸟的资源状况进行调查.共记录到水鸟72种,隶属于7目14科.此外发现16种新记录.青海湖水鸟春季迁徙高峰期在4月下旬.不同生境水鸟的多样性也不同,砂石海滩如鸬鹚岛和二郎剑的水鸟多样性在各季节都较低,可能是由于砂石生境中食物较少的缘故.     

浅析旅游活动对野生动物的影响——以西藏雅鲁藏布江中游河谷黑颈鹤国家级自然保护区为例

利用警戒距离等指标来反映黑颈鹤对旅游干扰的耐受性,分析不同人类活动的强度和离水体的距离对黑颈鹤行为的影响,以及旅游活动对水鸟数量、种类的影响,旨在为其它同类型的自然保护地旅游建设提供参考。通过2017年1月至2019年12月的连续观测,记录鸟类种类、数量并进行对比分析;对旅游干扰源进行分类,探讨旅游开发建设活动对其它野生动物生境的影响。研究表明：(1)黑颈鹤的警戒距离与人类干扰的强度、离水体的距离呈显著负相关;(2)水鸟数量和种类明显受旅游活动强度的影响,旅游活动强度为轻的区域水鸟种类和数量较多;(3)旅游开发建设对其它野生动物的生境会造成一定程度的不利影响。同时针对正确处理旅游与环境、保护与发展之间的关系提出建议。     

呼伦贝尔草原黄羊春季采食生境的选择

本文采用数量化分析方法 ,对呼伦贝尔草原黄羊春季采食生境选择进行了研究。研究发现 ,影响呼伦贝尔草原黄羊春季采食生境选择的主要因子是放牧家畜干扰、水源、人为干扰 ,其次是坡度、坡位、坡向、植被类型、食物丰盛度 ,风向也有一定影响。其采食生境选择的倾向性依次为 :放牧家畜干扰距离 >2 0 0 0m ,水源距离≤ 10 0 0m ,坡度 5～ 2 5° ,人为干扰距离 >10 0 0m ,坡位在中坡 ,植被类型是针茅或针茅 羊草群落 ,食物丰盛度中等以上 ,阳坡或半阴半阳坡     

广西元宝山自然保护区黑熊春季栖息地选择

2009年2～4月,对元宝山自然保护区黑熊春季栖息地选择进行调查分析,Vanderloeg选择系数Wi和Scavia选择指数Ei表明：黑熊喜欢郁闭度〉50%、水源距离〈30 m、坡度小于20°～40°、避风性良好、坡向为南坡、坡位中坡位或上坡位、树径〉0.4 m,人为干扰距离〉100 m、海拔1 600～2 000 m...     

人为干扰对森林群落及生物多样性的影响

研究了人为干扰对森林群落及生物多样性的影响,结果表明,人为干扰对多样性影响存在差异,干扰强度在3级以上的群落,生物多样性指数下降,且强度越大,多样性指数越低。2级左右的中度干扰,多样性指数增高,符合生态学“中度干扰假说”理论,但完全未受人为干扰的多优种阔叶林多样性指数也高。人为干扰对群落的数量和类型影响明显,在人口聚居区,群落类型少,人为干扰的垂直空间范围在低地河谷为向上200 m的空间范围,在高地缓坡为聚居带向上和向下各100m的空间范围。     

黄河三角洲水鸟年度动态变化及其规律分析

黄河三角洲是东北亚内陆和环西太平洋地区鸟类迁徙路线上重要的停歇地、越冬地和繁殖地,有水库、近海滩涂、芦苇沼泽、河流、盐池、渔塘等多种湿地生态类型,水鸟资源丰富。作者在2009年,以每月一次的调查频度,对黄河三角洲地区水鸟资源进行调查,共调查水鸟种类计数97种,数量总计数334046,其中湿地依赖鸟种种类计数6种,湿地依赖鸟种数量计数44种,受胁水鸟种类计数10种,受胁水鸟数量计数21432只。在调查数据的基础上,作者对水鸟年度动态变化作了分析,研究水鸟的动态变化规律。     

3种小跌水景观空气负离子浓度分布特征

本研究以阳江银滩滨海旅游区3种景观小跌水为研究对象，进行微尺度下空气负离子浓度的分布观测。研究周期约为一年，按季度随机选择检测时间，2012年12月至2013年10月期间共检测12次，结果表明：在风速范围为1.1～2.3 m·s-1的情况下，滨海景观小跌水环境空气负离子浓度明显高于旅游区无水体的内路段，且高浓度尺度为以水体为中心半径0～1.5 m 处，1.5 m 之外随距离增加而浓度急剧下降，渐趋底线后缓和持平；小跌水负离子浓度与距离和湿度呈正相关关系，与温度相关性不大。小跌水是园林景观水体中最常用的形式，建议设计应缩短活动场地与水体间距离，增大两者接触面；适当种植遮阴乔木，通过合理的空间流向设计形成有利的风导向，从而最大程度地实现空气负离子对人体的保健效用。     

旅游干扰对鸟类多样性及取食距离的影响评价——以普达措国家公园为例

依据普达措国家公园内旅游活动形式的不同分别在公园的步道、观光公路以及不受旅游干扰的村庄进行调查研究。通过在不同的时段内记录鸟的种类、数量、取食距离及对应的客流量和车流量,分析旅游干扰与鸟类多样性及鸟类取食距离之间的关系。研究结果显示:干扰程度不同的3种生境下鸟类多样性也不同,最高为村庄,观光公路次之,旅游步道的鸟类多样性最低;客流量对鸟类多样性的影响很大,而车流量对鸟类多样性的影响较微弱;客流量与鸟类取食距离之间的关系因鸟种的不同而异,对鹬类及白鹡鸰(Motacilla alba)的取食距离的影响大于鸦科鸟类和游禽类。通过不同旅游干扰对鸟类多样性及取食距离的研究,为普达措国家公园的经营和管理提供参考。     

广西宜州龙江河畔赤腹松鼠春季栖息地选择

2008和2009年3—5月,采用直接观察法对广西宜州龙江河畔赤腹松鼠春季栖息地的选择进行调查和分析,结果表明：赤腹松鼠喜欢郁闭度好、水源距离10-50m、坡度20—40°、避风性良好、坡向东坡和南坡、坡位中坡位或上坡住、食物因子良好,人为干扰距离10-20m,海拔50—150m,乔木密度〈50株,灌木密度50～200株,乔木距离1～4m,灌木距离〈2m的栖息地;水源距离、坡度、海拔、灌木距离、人为干扰距离和灌木密度无显著差异（P〉0．05）,郁闭度、避风性、坡向、坡位、食物因子、乔木密度和乔木距离存在显著差异（P〈0．05）。     

杂谷脑河干旱河谷区灌丛植被种-面积与坡向及海拔梯度的相关性研究

在对杂谷脑河流域的干旱河谷植被进行全面踏查的基础上,综合选择具有典型性、代表性,且人畜干扰少的阴、阳两坡面,在两坡面各设3个海拔梯度,每个海拔梯度间隔约300 m,采用植物群落学的最小面积法对杂谷脑河干旱河谷区灌丛植被种-面积进行调查研究。结果表明:该区的维管植物及其灌木和草本不论在阳坡还是阴坡,随着海拔梯度的上升,它们的最小面积都在逐渐增大,而最小面积所含的种数也随之增大;在相近海拔梯度上,阴坡的最小面积都比阳坡大,且最小面积所含种数也发生规律性变化。     

微山湖喜鹊和池鹭巢址选择的研究

2011年3～5月使用直接观察法对微山湖新薛河湿地内的鸟类巢穴进行调查,共发现鸟类巢穴90个,其中喜鹊Pi-ca pica巢36个,池鹭Ardeola bacchus巢54个,其他鸟类的巢穴2个。对影响鸟类巢址选择的因素进行了分析,结果显示距水源的距离、营巢树高和营巢树是影响喜鹊巢址选择的主导因子,次要因子是巢距地面高度、距公路的距离和人为干扰状况,再次是巢分支数;距公路的距离、巢距地面的高度、营巢树胸径和营巢树高是影响池鹭巢址选择的主导因子,次要因子是距水源的距离、人为干扰状况和巢分支数。     

Herpetofaunal species richness responses to forest landscape structure in Arkansas

Species accumulation curves were used to study relationships between herpetofaunal richness and habitat characteristics on four watersheds in Arkansas that differed markedly with respect to management intensity. Selected habitat characteristics were estimated for stands containing the sample points and within buffers with radii of 250, 500 m, and 1 km surrounding the sample points. Richness of all three herpetofaunal groups (amphibians, reptiles, and all herpetofauna) was greater in hardwood forests than in pine or mixed pine–hardwood. For all three groups, the youngest forest age class had the most species. For amphibians and total herpetofauna, richness declined as stand ages increased. Reptiles had the highest richness at sample points with the lowest class of stand basal area (BA), whereas amphibians were richest at points having the highest BA. In contrast to expectations, there was no effect of distance from water on richness of any taxa; however, we may have had incomplete data on the spatial distribution of small ponds outside the sample plots because they were not recorded in the GIS data. Results for distance to roads were ambiguous, but with more separation of compared curves as more plots were sampled, a positive influence of road proximity was suggested. There was a positive effect of buffer age diversity at the 250 m scale for all three herpetofaunal groups, but less so at scales >250 m except for amphibians, which also showed a positive effect at the 1 km scale. The two most intensively managed watersheds had higher species richness than the two less intensively managed watersheds for reptiles, amphibians, and both groups combined. In this study landscape, where urban and agricultural influences were minimal, we did not observe negative impacts of forest management and associated activities, and local habitat heterogeneity created by silviculture often had a positive effect on herpetofaunal species richness.     

Impacts of resource extraction on forest structure and diversity in Bardia National Park,Nepal

Repeated biomass harvesting for human livelihood needs can cause significant changes in forest structure, composition and diversity. Such impacts have often been associated with the distance to villages and their size, but the effects of individual villages in relation to their characteristics have been little studied. Focussing on the issues around communities’ impacts on the forest, this research aimed to understand how resource extraction by two Buffer Zone villages in Nepal's Bardia National Park affects forest structure and diversity. Tree density, basal area, diameter at breast height (DBH), species richness, two diversity indices and disturbance indices were recorded in 108 plots in 12 transects, from March till May 2005, within the park along the village boundaries, where resource extraction occurs, and in the core park area which is isolated from human disturbance. Forest subject to resource extraction had a lower density of trees, smaller DBH and lower species richness and diversity. Forest disturbance declined with distance from the villages but the two villages differed widely in their impact on the forest. Resource use was more intensive in Shivapur village and percentage of trees lopped, average lopping intensity and numbers of dung piles were statistically significant. This was mainly due to the lack of access to Buffer Zone community Forest for Shivapur households. Interviews with villagers suggested that there have been changes in species availability compared to 5 years ago. Households also underestimated the impact of their resource extraction, which may prevent them from changing their behaviour to benefit conservation. It is clear that understanding rural communities’ needs, their framing of resource extraction and utilisation, and dependence on forest resources will be very helpful for long term conservation measures.     

The importance of seedling competition in the segregation of spruce and fir in the southern Appalachians

Fraser fir (Abies fraseri [Pursh] Poir.) and red spruce (Picea rubens Sarg.) are codominants of southern Appalachian spruce-fir forests. Fraser fir generally dominates above 1740 m, while red spruce usually dominates below this elevation. This study was designed to determine whether the present segregation of the two species along elevational gradients is associated with seedling competition or contrasting physiological responses to environmental factors. Seedlings were grown for two years in a replacement series experiment along two elevational transects extending from 1300 m to 1900 m, and harvested for growth analysis.Competition increased with decreasing elevation and Fraser fir was apparently the stronger competitor. Mortality was inversely correlated with elevation and was most evident in red spruce in May, and in fir in late summer. Fir growth increased with elevation and red spruce grew most at the middle elevation (1600 m). Neither competitive interactions nor growth responses completely explained the elevational segregation of red spruce and Fraser fir. We hypothesize that the early-successional Fraser fir quickly dominates at higher elevations following disturbance and that continued disturbance will favor its dominance at higher elevations. However, the late-successional noncompetitive red spruce slowly establishes itself and, while consistently present, may only dominate in the absence of disturbance and where other species are at the margins of their distribution.     

Patterns in spatial extent of gap influence on understory plant communities

Gap formation in forests can have impacts on forest ecosystems beyond the physical boundary of the canopy opening. The extent of gap influence may affect responses of many components of forest ecosystems to gap formation on stand and landscape scales. In this study, spatial extent of gap influence on understory plant communities was investigated in and around 0.1 and 0.4 ha harvested canopy gaps in four young Douglas-fir (Psuedotsuga menziesii) dominated stands in western Oregon. In larger gaps, the influence of gap creation on understory plant communities in surrounding forests was minimal. The area showing evidence of gap influence extended a maximum of 2 m beyond the edge of the canopy opening, suggesting that the area affected by gap creation did not differ greatly from the area of physical canopy removal. In smaller gaps, influence of the gap did not extend to the edge of the canopy opening. In fact, the area in which understory vegetation was influenced by gap creation was smaller than the physical canopy opening. Gap influence appears to be limited to areas where ruderal or competitor species are able to replace stress-tolerator species, likely due to elimination or reduction of these species by physical disturbance or competition. The limited gap influence extent exhibited here indicates that gap creation may not have a significant effect on understory plant communities beyond the physical canopy opening. This suggests a limited effectiveness of gaps, especially smaller gaps, as a tool for management of understory plant diversity, and perhaps biodiversity in general, on a larger scale.