Are hybrid species more fit than ancestral parent species in the current hybrid species habitats?

Hybrid speciation is thought to be facilitated by escape of early generation hybrids into new habitats, subsequent environmental selection and adaptation. Here, we ask whether two homoploid hybrid plant species (Helianthus anomalus, H. deserticola) diverged sufficiently from their ancestral parent species (H. annuus, H. petiolaris) during hybrid speciation so that they are more fit than the parent species in hybrid species habitats. Hybrid and parental species were reciprocally transplanted into hybrid and parental habitats. Helianthus anomalus was more fit than parental species in the H. anomalus actively moving desert dune habitat. The abilities to tolerate burial and excavation and to obtain nutrients appear to be important for success in the H. anomalus habitat. In contrast, H. deserticola failed to outperform the parental species in the H. deserticola stabilized desert dune habitat, and several possible explanations are discussed. The home site advantage of H. anomalus is consistent with environmental selection having been a mechanism for adaptive divergence and hybrid speciation and supports the use of H. anomalus as a valuable system for further assessment of environmental selection and adaptive traits.     

Novel distribution pattern between coexisting sexual and obligate asexual variants of the true estuarine macroalga Ulva prolifera

Where sexual and asexual forms coexist within a species, the asexuals are often found to be prevalent in marginal habitats. This asexual distribution pattern has received evolutionary attention linked to the paradox of sex. In many marine species, there is a distributional trend of asexual modes being more common in lower salinity waters regarded as the ecogeographic marginal, being explained by negative effects of low salinities on sexual reproductive success. However, the distribution pattern of estuarine species recently adapted to low salinity waters has remained unknown. The brackish macroalga Ulva prolifera being a major benthic component of estuarine ecosystems includes a sexual variant and obligate asexual variants by means of motile spores. We examined the sexual–asexual distribution pattern of this alga along a salinity gradient in river estuaries. Surprisingly, opposite to the distributional trend of marine organisms, the results clearly showed the persistent predominance of sexuals in the lower salinity reaches than the asexuals. In addition, a frequent alternating of dioecious gametophytes and sporophytes in the sexual population was observed, suggesting the sexual reproductive process would be robustly performed in the low salinity waters. Considering U. prolifera had evolved from the ancestral marine species to become a true estuarine species of which the core habitat is the low salinity reaches, in a broad sense its sexual–asexual distribution pattern would be involved in asexual marginal occupations of the species range previously reported in other organisms. Based on the frozen niche variation model, we can give a concise explanation for the evolutionary process of this pattern; multiple asexuals with frozen genotypic variation had arisen from sexual ancestors undergoing low salinity adaptation and share the estuarine habitat with the sexuals at present.     

Relationship among settling,demography and habitat selection: an approach and a case study

Summary We explore the demographic consequences of site selection by animals on their abundance among habitats. We found that pre and post settling survivorship are important links between the behavioral decisions where to settle and the distribution of a population among habitats. This was demonstrated for 10 generations of the desert isopod, Hemilepistus reaumuri, in three habitats in the Negev Desert, Israel. The populations exhibit low survivorship before settling (12%) and high survivorship (55%) after settling. According to our model this implies high site selection. Theoretical considerations and the case study led us to suggest the following relationship among settling, demography and habitat selection: 1) Individuals search for suitable settling sites to inhabit and reproduce. 2) Their decision where and when to settle is a cost benefit decision. They weigh the benefit of searching for a high quality site against mortality due to increased searching time. 3) The individual's decision to settle determines the pre and post settling survivorship pattern. 4) Survivorship pattern dictates density pattern in time and space. 5) Density pattern in a given habitat determines its quality for the individual. 6) Settling selection among habitats and the number of safe sites controls the distribution of densities among habitats.     

Nest placement and nesting success in two finch species colonizing a recently established plantation in an arid region

This study examines variations in nest placement and its effects on nesting success in the Desert Finch (Rhodospiza obsoleta) and the Linnet (Carduelis cannabina) which coexist in a recently established plantation (novel habitat) in a desert region in Jordan. A comparison with other habitats (old plantation in the desert and native, Mediterranean-type, habitat of the Linnet) showed that each species displayed similarity in nest placement patterns across habitats. Nest concealment predicted nesting outcome in the Linnet, whereas nest height predicted nesting outcome in the Desert Finch. Daily survival rates were significantly higher in Desert Finch nests compared to the Linnet's, perhaps because Desert Finches placed nests higher in the novel habitat, which lacked aerial nest predators. In accordance with predation theories of life history evolution, we provide evidence that variation in nest placement among the two species in a novel habitat resulted from previous exposure to different predation risks.     

人工固沙植被恢复对地表节肢动物群落组成及多样性的影响

人工绿洲是干旱区主要的自然景观之一,为了维护绿洲稳定而营建的防护林强烈改变地表生态水文过程,进而影响着地上和地下生物多样性。然而,以往的研究对地上植被关注较多,而对土壤动物研究较少。以张掖绿洲外围人工固沙植被群落和天然固沙植被群落为研究对象,探讨人工固沙植被恢复对荒漠地表节肢动物群落组成及多样性的影响及不同动物类群对植被变化的响应模式。研究表明,天然固沙植被群落转变为人工固沙植被群落显著降低了地表节肢动物数量,但提高了地表节肢动物类群丰富度和多样性,这在5月份表现尤为明显。植被类型对地表节肢动物群落的影响不同,8月人工柽柳林群落地表节肢动物活动密度、类群丰富度和多样性均显著高于人工梭梭林群落。人工固沙植被恢复显著降低了适应荒漠环境的拟步甲科甲虫,而蚁科和部分蜘蛛的数量显著增加,它们对人工固沙植被恢复的响应模式不同决定了群落结构及多样性的变化规律。此外,研究还发现一些地表节肢动物类群对不同生境具有强烈的指示作用,如拟步甲科等可指示荒漠生境,潮虫科等可指示梭梭林生境,而蠼螋科和狼蛛科等可指示柽柳林生境。综上所述,人工栽植固沙灌木形成的固沙植被群落导致了一些适应荒漠环境的地表节肢动物类群的数量降低,但也为更多的地表节肢动物类群提供了适应栖居环境和充足的食物资源等,从而提高了地表节肢动物的多样性。     

Distributions of forest birds and butterflies in the Andaman islands, Bay of Bengal: nested patterns and processes

The distributional patterns of forest birds and butterflies in the Andaman islands, an oceanic chain located off SE Asia, were tested for nestedness. Both taxa were highly nested. Nestedness could be due to colonization or extinction processes, area or distance effects or nestedness of habitats. Nestedness in forest bird distributions were strongly influenced by area and habitat related factors. Habitats were significantly nested in all three island groups, however most strongly for the North Andamans. However forest bird distributions in the North Andamans, as indicated by row order in the packed matrix, was not correlated with habitat diversity, suggesting that habitat related factors alone cannot account for these patterns. Other causal influences could be passive sampling, where common and abundant species and habitats are more likely to have a widespread distribution than rare species and habitats. The nested subset pattern seen in two unrelated taxa suggests that the Andamans are extinction dominated and that the protection of forests on large islands is critical for the conservation of its biodiversity.     

DISTRIBUTION ECOLOGY OF HAPLOPAPPUS AND CHRYSOTHAMNUS IN THE MOJAVE DESERT. I. NICHE POSITION AND NICHE SHIFTS ON NORTH-FACING GRANITIC SLOPES

The close systematic affinities between the composite genera Haplopappus and Chrysothamnus, including different points of contact with “intergeneric” hybrids, are reviewed. The Mohave Desert has several shrubby representatives of each genus, and at census sites from the east-central New York Mountains to buttes at the extreme western end of the desert, north-facing granitic slopes at the foothills of mountain ranges support four Haplopappus species (H. cuneatus. H. laricifolius, H. linearifolias and H. cooperi) and one Chrysothamnus (C. teretifolius). These five species occupy “distributional niches” represented as ranges and areas of dominance on the habitat plane of slope angle and proportion of rocks in the substrate. Central desert sites have four species (excluding C. teretifolius); peripheral desert sites always include C. teretifolius rather than H. laricifolius and support two to four species depending on the size and isolation of the suitable habitat area. Species may occupy different positions on the habitat gradient depending on species number at the site, moisture availability, and in particular competition from other species. C. teretifolius appears to be favored when population turnover rates are high, either in disturbed sites or on natural islands of habitat.     

人工柠条-荒漠草地交错带拟步甲昆虫群落多样性

选取宁夏东部盐池县人工柠条灌丛-荒漠草地交错带为研究样地,以距离梯度形式,利用巴氏诱罐法对拟步甲科昆虫群落多样性进行了调查,研究了边缘效应对拟步甲昆虫群落多样性的影响。共采集拟步甲昆虫1405只,分属8属13种。结果表明,克小鳖甲和弯齿琵甲个体数量分别占总个体数的32.74%和43.27%,为该地区的优势种类。拟步甲昆虫在人工柠条灌丛-荒漠草地交错带的分布可分为3种类型,优势种克小鳖甲和弯齿琵甲属于栖息地广布型,但二者并没有表现出十分均匀的适应性,而且他们在各样带的分布呈显著负相关,克小鳖甲的分布趋向于沙生荒漠环境,弯齿琵甲的分布趋向于柠条灌丛;常见种蒙古漠王、小皮鳖甲的分布偏向于喜好荒漠草地;异距琵甲、奥氏真土甲、网目土甲和淡红毛隐甲的分布则偏向于喜好柠条灌丛。拟步甲昆虫丰富度与Shannon-Wiener多样性沿边缘分别向柠条灌丛和荒漠草地内部降低,个体数量总体上沿柠条灌丛、交错带向荒漠草地内部降低,但各样带差异不显著。从季节动态看,荒漠草地和柠条灌丛物种多样性季节变化相似,3种生境拟步甲活动密度季节变化相似。边缘效应强度分析呈现边缘正效应。CCA排序图显示分类地位相近的物种在生态适应上具有趋同性。多元回归分析表明,植被密度影响拟步甲昆虫群落的优势种和个体数量,植被盖度和高度分别影响拟步甲群落的均匀度和丰富度。主坐标分析(PCo A)排序表明人工柠条灌丛-荒漠草地交错带的拟步甲昆虫群落组成与柠条灌丛内部没有明显分化,但趋于向柠条灌丛生境演替。     

Interspecific differences in population trends of Spanish birds are related to habitat and climatic preferences

Aim Animal monitoring programmes have allowed analyses of population trends, most of which now comment on the possible effect of global climate change. However, the relationship between the interspecific variation in population trends and species traits, such as habitat preferences, niche breadth or distribution patterns, has received little attention, in spite of its usefulness in the construction of ecological generalizations. The objectives of this study were: (1) to determine whether there are characteristics shared among species with upwards or downwards trends, and (2) to assess whether population changes agree with what could be expected under global warming (a decrease in species typical of cooler environments). Location The Spanish part of the Iberian Peninsula (c. 500,000 km²) in the south‐western part of the Mediterranean Basin. Methods We modelled recent breeding population changes (1996–2004), in areas without apparent land use changes, for 57 common passerine birds with species‐specific ecological and distributional patterns as explanatory variables. Results One‐half of these species have shown a generalized pattern towards the increase of their populations, while only one‐tenth showed a significant decrease. One half (54%) of the interspecific variability in yearly population trends is explained considering species‐specific traits. Species showing more marked increases preferred wooded habitats, were habitat generalists and occupied warmer and wetter areas, while moderate decreases were found for open country habitats in drier areas. Main conclusions The coherent pattern in population trends we found disagrees with the proposed detrimental effect of global warming on bird populations of western Europe, which is expected to be more intense in bird species inhabiting cooler areas and habitats. Such a pattern suggests that factors other than the increase in temperature may be brought to discussions on global change as relevant components to explain recent changes in biodiversity.     

Control of arthropod abundance, richness, and composition in a heterogeneous desert city

There is a demand for mechanistic studies to explore underlying drivers behind observed patterns of biodiversity in urban areas. We describe a two-year field experiment in which we manipulated bottom-up (resource availability) and top-down (bird predation) forces on arthropod communities associated with a native plant, Encelia farinosa, across three land-use types—urban, desert remnant, and outlying natural desert—in the Phoenix metropolitan area, Arizona, USA. We monitored the trophic structure, richness, and similarity of the arthropod communities on these manipulated plants over a two-year period. We predicted that (1) increased water resources increase plant productivity, (2) increased productivity increases arthropod abundances, and (3) in the urban habitat, top-down forces are greater than in other habitats and limit arthropod abundances. We also predicted that urban remnant habitats are more similar to urban habitats in terms of arthropod richness and composition. Strong interannual differences due to an unusual cold and dry winter in the first year suppressed plant growth in all but urban habitats, and arthropod abundances in all habitats were severely reduced. In the following year, arthropod abundances in desert and remnant habitats were higher than in urban habitats. Water had positive effects on plant growth and arthropod abundance, but these water effects emerged through complex interactions with habitat type and the presence/absence of cages used to reduce bird predation. Plants grew larger in urban habitats, and phenology also differed between urban and desert habitats. The results from caging suggest that bird predation may not be as important in cities as previously thought, and that arthropods may retard plant growth. As expected, desert communities are strongly bottom-up regulated, but contrary to predictions, we did not find evidence for strong top-down control in the city. Remnant habitats were intermediate between desert and urban habitats in terms of diversity, richness, evenness, arthropod composition and phenology, with urban habitats generally lowest in terms of diversity, richness, and evenness. Our study shows that control of biodiversity is strongly altered in urban areas, influenced by subtle shifts in top-down and bottom-up controls that are often superseded by climatic variations and habitat type.     

Distribution,habitat and conservation status of desert pupfish (Cyprinodon macularius) in the Lower Colorado River Basin,Mexico

In order to better determine the currentstatus of desert pupfish populations (Cyprinodon macularius macularius) in the LowerColorado River Basin of Mexico, bimonthly fishsampling and habitat evaluations were carriedout from September 1996 to August 1997 in sixlocalities of Baja California and Sonora.Desert pupfish were collected using minnowseines and traps. Four sampling sites are inSonora, in shallow marginal habitats of theCiénega Santa Clara (Hunters' Camp, Outletof the Welton-Mohawk channel, El Doctor andFlor del Desierto) and two are in BajaCalifornia (Cerro Prieto and streams south ofCerro Prieto). The most abundant fish speciessampled was native desert pupfish (C.macularius, 59%) followed by sailfin molly(Poecilia latipinna, 19%), redbellytilapia (Tilapia cf. zilli, 10%) and western mosquito fish (Gambusiaaffinis, 7%). Significant temporalfluctuations in distribution and abundance ofdesert pupfish populations, as previouslyreported for these populations, was againdocumented. The main anthropogenic factorsaffecting distribution and abundance of desertpupfish populations in the Mexican portion ofthe Lower Colorado River Basin are progressivealteration of aquatic and riparian habitats, aswell as presence of exotic fishes that havecaused the displacement or elimination ofnative fish populations. Both habitat andpresence of the desert pupfish populations inthe study area are controlled by theperiodicity, quality and volume of dischargesinto the Mexican portion of the basin from theUnited States.     

Assessment of habitat quality for four small mammal species of the Monte Desert, Argentina

In the temperate desert of Argentina, the combined action of climatic and anthropogenic factors has contributed to the formation of a highly heterogeneous landscape. In the central region of the Monte desert, four small mammal species (Eligmodontia typus, Calomys musculinus, Akodon molinae and Graomys griseoflavus) coexist and show different habitat uses in response to spatial variability. Three main habitat types are present in the region: mesquite forest, the creosotebush community and sand dunes. These habitat types are present also in the surrounding grazing area.The objective of this study was to determine habitat quality for these species in a protected area (Reserve MaB Ñacuñán) and in the adjacent grazed area. For each species we estimated demographic parameters that are highly correlated to fitness in each habitat, and for both treatments (protected and grazed).We found that the protected area offered a higher quality habitat than the grazed area for all species, but principally A. molinae and G. griseoflavus. At a local scale, we found that A. molinae and C. musculinus clearly showed higher fitness in the more complex habitats as the creosotebush community and the mesquite forest. In contrast, for E. typus, open and simplest patches, such as sand dunes, were optimal for its survival and reproduction.     

Remote sensing variables as predictors of habitat suitability of the viscacha rat (<Emphasis Type="Italic">Octomys mimax</Emphasis>), a rock-dwelling mammal living in a desert environment

Identifying high-quality habitats across large areas is a central goal in biodiversity conservation. Remotely sensed data provide the opportunity to study different habitat characteristics (e.g., landscape topography, soil, vegetation cover, climatic factors) that are difficult to identify at high spatial and temporal resolution on the basis of field studies. Our goal was to evaluate the applicability of remotely sensed information as a potential tool for modeling habitat suitability of the viscacha rat (Octomys mimax), a rock-dwelling species that lives in a desert ecosystem. We fitted models considering raw indices (i.e., green indices, Brightness Index (BI) and temperature) and their derived texture measures on locations used by and available for the viscacha rat. The habitat preferences identified in our models are consistent with results of field studies of landscape use by the viscacha rat. Rocky habitats were well differentiated by the second-order contrast of BI, instead of BI only, making an important contribution to the global model by capturing the heterogeneity of the substratum. Furthermore, rocky habitats are able to maintain more vegetation than much of the surrounding desert; hence, their availability might be estimated using SATVI (Soil Adjusted Total Vegetation Index) and its derived texture measures: second-order contrast and entropy. This is the first study that evaluates the usefulness of remotely sensed data for predicting and mapping habitat suitability for a small-bodied rock dwelling species in a desert environment. Our results may contribute to conservation efforts focused on these habitat specialist species by using good predictors of habitat quality.     

Habitat use,but not gene flow,is influenced by human activities in two ecotypes of Egyptian fruit bat (Rousettus aegyptiacus)

Understanding the ecological, behavioural and evolutionary response of organisms to changing environments is of primary importance in a human‐altered world. It is crucial to elucidate how human activities alter gene flow and what are the consequences for the genetic structure of a species. We studied two lineages of the Egyptian fruit bat (Rousettus aegyptiacus) throughout the contact zone between mesic and arid Ecozones in the Middle East to evaluate the species' response to the growing proportion of human‐altered habitats in the desert. We integrated population genetics, morphometrics and movement ecology to analyse population structure, morphological variation and habitat use from GPS‐ or radio‐tagged individuals from both desert and Mediterranean areas. We classified the spatial distribution and environmental stratification by describing physical–geographical conditions and land cover. We analysed this information to estimate patch occupancy and used an isolation‐by‐resistance approach to model gene flow patterns. Our results suggest that lineages from desert and Mediterranean habitats, despite their admixture, are isolated by environment and by adaptation supporting their classification as ecotypes. We found a positive effect of human‐altered habitats on patch occupancy and habitat use of fruit bats by increasing the availability of roosting and foraging areas. While this commensalism promotes the distribution of fruit bats throughout the Middle East, gene flow between colonies has not been altered by human activities. This discrepancy between habitat use and gene flow patterns may, therefore, be explained by the breeding system of the species and modifications of natal dispersal patterns.     

内蒙古贺兰山国家级自然保护区荒漠沙蜥春秋季生境选择

为更好的了解及保护荒漠沙蜥(Phrynocephalus przewalskii)资源,于2017年5—6月和9—10月,在内蒙古贺兰山国家级自然保护区采用样线调查法对其春、秋2季的生境选择进行研究。春季测定了92个荒漠沙蜥生境利用样方和64个对照样方、秋季测定了71个荒漠沙蜥生境利用样方和76个对照样方的共13种生态因子。利用拟合优度卡方检验、VanderploegScavia′s选择指数、 Mann-White U检验和逐步判别分析确定影响其春秋季生境选择的关键因子。结果表明,荒漠沙蜥的生境选择存在季节性差异。春季一般选择食物丰富度高,隐蔽性好,光照强,地表温度高、湿度低的生境,既保证安全因素又利于达到最适体温,满足繁殖需求;秋季偏好选择土壤质地疏松,食物丰富度高和中的草甸地区,便于隐蔽及累积食物,以满足其躲避天敌、储存越冬能量的需要。     

The Importance of Acacia Trees for Insectivorous Bats and Arthropods in the Arava Desert

Anthropogenic habitat modification often has a profound negative impact on the flora and fauna of an ecosystem. In parts of the Middle East, ephemeral rivers (wadis) are characterised by stands of acacia trees. Green, flourishing assemblages of these trees are in decline in several countries, most likely due to human-induced water stress and habitat changes. We examined the importance of healthy acacia stands for bats and their arthropod prey in comparison to other natural and artificial habitats available in the Arava desert of Israel. We assessed bat activity and species richness through acoustic monitoring for entire nights and concurrently collected arthropods using light and pit traps. Dense green stands of acacia trees were the most important natural desert habitat for insectivorous bats. Irrigated gardens and parks in villages and fields of date palms had high arthropod levels but only village sites rivalled acacia trees in bat activity level. We confirmed up to 13 bat species around a single patch of acacia trees; one of the richest sites in any natural desert habitat in Israel. Some bat species utilised artificial sites; others were found almost exclusively in natural habitats. Two rare species (Barbastella leucomelas and Nycteris thebaica) were identified solely around acacia trees. We provide strong evidence that acacia trees are of unique importance to the community of insectivorous desert-dwelling bats, and that the health of the trees is crucial to their value as a foraging resource. Consequently, conservation efforts for acacia habitats, and in particular for the green more densely packed stands of trees, need to increase to protect this vital habitat for an entire community of protected bats.     

Foraging strategies and recruitment behaviour in the European harvester ant Messor rufitarsis (F.)

Summary Most of the approximately 40 species of the Old World harvester ant genus Messor live in warm and dry Mediterranean areas. One species, M. rufitarsis, is found in isolated Northern temperate habitats in Rheinhessen and the Rheingau area in Hessen, West Germany. These habitats are characterized by a great diversity of spermatophytes, so that permanently changing seed resources are available for the ants during the growing period. M. rufitarsis has maintained its granivorous specialization under these habitat conditions and collects most of the seed resources, which show a large fluctuation in quantity, quality and distributional pattern throughout the year. M. rufitarsis is very flexible in using different foraging strategies. For discovering newly ripened food resources and collecting wide-spread single seeds, an individual foraging strategy is used. However, dense seed resources are exploited through an effective recruitment system. Nestmates are guided to the feeding place by means of orientation-recruitment trails from Dufour's gland. Additional invitation behaviour enhances the success of recruitment. From analysis of slow-motion movies it is concluded that stridulation is the crucial signal of the invitation behaviour.     

Ecological traps and species distribution models: a challenge for prioritizing areas of conservation importance

Species distribution models analyse how species use different types of habitats. Their spatial predictions are often used to prioritize areas for conservation. Individuals may, however, prefer settling in habitat types of low quality compared to other available habitats. This ecological trap phenomenon is usually studied in a small number of habitat patches and consequences at the landscape level are largely unknown. It is therefore often unclear whether the spatial pattern of habitat use is aligned with the behavioural decisions made by the individuals during habitat selection or reflects actual variation in the quality of different habitat types. As species distribution models analyse the pattern of occurrence in different habitats, there is a conservation interest in examining what their predictions mean in terms of habitat quality when ecological traps are operating. Previous work in Belgium showed that red-backed shrikes Lanius collurio are more attracted to newly available clear-cut habitat in plantation forests than to the traditionally used farmland habitat. We developed models with shrike distribution data and compared their predictions with spatial variation in shrike reproductive performance used as a proxy for habitat quality. Models accurately predicted shrike distribution and identified the preferred clear-cut patches as the most frequently used habitat, but reproductive performance was lower in clear-cut areas than in farmland. With human-induced rapid environmental changes, organisms may indeed be attracted to low-quality habitats and occupy them at high densities. Consequently, the predictions of statistical models based on occurrence records may not align with variation in significant population parameters for the maintenance of the species. When species expand their range to novel habitats, such models are useful to document the spatial distribution of the organisms, but data on population growth rates are worth collecting before using model predictions to guide the spatial prioritization of conservation actions.     

阿尔金山自然保护区基于野牦牛、藏野驴、藏羚羊适宜栖息地的生态容量估测

阿尔金山国家级自然保护区保护了以野牦牛(Bos mutus)、藏野驴(Equus kiang)、藏羚羊(Pantholops hodgsoni)为代表的青藏高原特有野生动物及其栖息地,但是近年来野生动物数量的快速增长引发了栖息地退化的问题,科学量化阿尔金山自然保护区各类栖息地对野牦牛、藏羚羊、藏野驴的生态容量,并提出相应的野生动物管理措施,是实现保护区可持续管理的根本途径。本文应用遥感技术和地面调查相结合的方法,系统分析了保护区内野牦牛、藏野驴和藏羚羊的栖息地需求,建立了植物生物量和NDVI的关系模型,结合三类野生动物的食性分析,估测了适宜栖息地(高寒草原、高寒荒漠草原、高寒草甸、高寒荒漠)为三类野生动物提供的可食植物量,推算了适宜栖息地和整个保护区可以承载三类野生动物的生态容量。结果表明:阿尔金山自然保护区内野牦牛、藏野驴和藏羚羊的适宜栖息地面积分别为31866.07、24035.51、24035.51 km~2,三类野生动物的适宜栖息地之间相互重叠,藏野驴和藏羚羊的适宜栖息地基本相同;全保护区内,高寒草原、高寒荒漠草原、高寒荒漠和高寒草甸分别提供了3944.91×10~4、3126.32×10~4、138.19×10~4、564.49×10~4kg可食植物量;结合三类野生动物的栖息地重叠程度及食物需求量分析,得出阿尔金山保护区的最大生态容量为野牦牛7951头/a、藏野驴6907头/a、藏羚羊27094只/a;结合三类野生动物对食物资源的占有率估计,得出阿尔金山三类野生动物的生态容量变幅为野牦牛3976—7156头/a,藏野驴3454—6216头/a、藏羚羊13547—24385只/a。根据阿尔金山自然保护区各类栖息地对三类野生动物的生态容量,提出适当控制藏野驴种群数量、增加藏羚羊种群数量的建议,以促进野生动物种群数量的持续增长和栖息地的有效保护。