小相岭大熊猫与放牧家畜的生境选择

利用 Forage Ratio指数对小相岭山系大熊猫与放牧牲畜的生境选择进行了比较研究 ,研究涉及 1 1种生境因子。研究结果表明 ,大熊猫喜欢选择在山体的脊部和中部的凸坡 ,坡向南坡 ,喜欢选择 0～ 2 4 %的灌木盖度 ,喜欢竹子盖度大于 5 0 %的原始针叶林 ,对坡度、乔木高度、乔木郁闭度、灌木高度不存在选择性 ,都为随机利用。放牧牲畜喜欢选择利用复合坡、山体的下部、坡度小于 2 0°的山坡 ;喜欢利用的生境类型是草坡和灌丛 ;选择的森林起源是次生林 ;所利用生境的乔木高度为 5～ 9m,对坡向、乔木郁闭度、灌木高度、灌木盖度、竹子盖度都随机利用。放牧家畜与大熊猫在对生境因子的利用上有许多共同点 ,对许多因子类型大多都是随机利用 ,因而 ,在对一些生境因子的利用上 ,放牧对大熊猫的活动会产生一定的影响。同时 ,它们在生境选择上也存在一定的差异 ,特别是在对植被类型和森林起源的选择上差异较大 ,只要合理的规划和控制放牧活动 ,也就可能达到大熊猫保护与社区经济协调发展的目的     

Changes in habitat selection patterns of the gray partridge Perdix perdix in relation to agricultural landscape dynamics over the past two decades

相似文献   

太行山猕猴的冬季生境选择

2007 年11 月至2008 年2 月,在太行山猕猴国家级自然保护区愚公保护站,根据观察到的猕猴活动痕迹和位置,设置了180 个10 m × 10 m 的样方。在这些样方中,对10 个生态因子(地形、海拔高度、坡位、坡向、坡度、离水源距离、人为干扰、郁闭度、隐蔽度、平均胸径)进行了调查分析,以期了解太行山猕猴的冬季生境选择特征。结果表明:太行山猕猴在冬季喜好选择的生境特征为:倾向于围绕大树(乔木平均胸径> 15 cm)活动;较之其它季节,冬季的猕猴更愿意接近人类居所(< 2 000 m),并选择离水源近(< 1 000 m)的地方活动,说明直接饮水可能是猕猴在干旱冬季获得足量水分的重要途径;冬季猕猴喜欢在坡度为15° ～40°、郁闭度< 60% 的阳坡活动,活动区域的海拔高度为1 000 ～1 300 m。猕猴对生境中地形特征和坡位无明显偏好,对活动地点的隐蔽条件也无特殊要求。文中还对所选择的生态因子进行了主成分分析,结果表明,前5 个主成分的特征值均大于1,其累积贡献率达到70.713% ,可以较好地反映猕猴的冬季生境特征。     

过去二十年贵州黑叶猴分布与种群动态及致危因子分析(英文)

本文通过整理相关文献与政府报告数据并结合我们在贵州的最新调查与监测数据,总结过去20年间黑叶猴在贵州的分布、种群变动及其所面临的主要威胁,并在此基础上提出相关的保护管理建议。贵州黑叶猴野生种群在过去20年间增长了约10%～20%:从20世纪90年代的约109群1000只增加到现在的约132～137群1160～1200只。但同期黑叶猴已从5个原有的分布点绝迹,现仅存于大沙河、柏箐、麻阳河、宽阔水和野钟等5个保护区,总面积约912km2。现有的5个隔离分布点保存有全球黑叶猴野生种群(1800～2000)的约62%,是黑叶猴物种保存的最关键地区,并应该给于保护管理的优先考虑。偷猎压力在贵州相对较小:在过去的20年间仅有3次偷猎的官方记录。黑叶猴在贵州所面临的主要威胁是栖息地的丧失与退化。其主要表现形式有:以农作物和烟草种植为目的的耕地扩大,以做饭、取暖以及烟叶烘烤为目的的薪材需求,以及家畜(主要是山羊)的过度放牧。     

Roosting site selection in the endangered damselfly, Coenagrion mercuriale, and implications for habitat design

A successful conservation strategy for an insect species should address the habitat requirements of all life stages and all activities performed by those life stages. In this paper the night-time roosting habitat and behaviour of the endangered damselfly Coenagrion mercuriale (Odonata: Coenagrionidae) was investigated by marking damselflies with UV fluorescent paint. Night-time observations revealed that individuals did not roost together and those that were recorded on more than one occasion did not return to the same spot each night. There was no apparent preference for roosting close to the watercourses. C. mercuriale roosted towards the top of the vegetation and this vegetation was considerably taller than the mean height of the vegetation in the study area. Adults were strongly associated with two tussock-forming monocots, Juncus inflexus and Deschampsia cespitosa. Differences in the abundance of these plants were shown to result in large differences in the numbers of C. mercuriale roosting in different parts of the site. The importance of providing these structural elements of habitat as part of a wider conservation strategy for this species is discussed.     

Mother-cub relationships in giant pandas in the Qinling Mountains,China, with comment on rescuing abandoned cubs

Six cases of mother-cub relationships in wild giant pandas (Ailuropoda melanoleuca) were observed in the Qinling Mountains, China. It was found that panda cubs are normally left alone in the den for 4–8 h while mothers forage. The mother's absence during bouts of foraging should be considered when rescuing abandoned cubs in order to avoid adding to the decline of the wild population. © 1994 Wiley-Liss, Inc.     

Habitat selection by larvae of a fluvial lamprey, <Emphasis Type="Italic">Lethenteron reissneri</Emphasis>, in a small stream and an experimental aquarium

Habitat selection by fluvial lamprey larvae, Lethenteron reissneri (Petromyzontidae), was studied in a natural stream and an experimental aquarium to clarify microhabitat requirements for future conservation of natural populations. A gross collection survey of lamprey larvae in the Monbetsu River, southeastern Hokkaido, Japan, revealed a remarkable bias toward distribution in sandy-mud beds. An analysis using Jacobs' electivity index showed that the larvae selectively utilized spaces having regard to shallow water, weak current, deep sandy-mud, and fine substrate particles. A comparison of microhabitat use between small- (≤5 cm) and large-sized larvae (>5 cm) indicated that the latter utilized the space with greater ranges in both water depth and substrate particle size than the former. Both the field survey and laboratory experiments on larval selectivity of physical habitat variables clearly demonstrated that substrate particle size was the most important variable for small-sized larvae whereas both water depth and substrate depth were more important for large larvae. These findings should be applicable in directing attempts at fluvial habitat restoration for conservation of this endangered lamprey species. Received: November 1, 2000 / Revised: September 12, 2001 / Accepted: October 18, 2001     

Designing a conservation plan for protecting the habitat for giant pandas in the Qionglai mountain range, China

Population viability of the giant panda ( Ailuropoda melanoleuca ) is threatened by small population sizes in scattered isolated habitat areas. Designing a conservation plan for protecting and connecting the fragmented habitat will improve the chances for survival of this endangered species. For such a plan, this study assessed the overall habitat suitability for the species in the Qionglai mountain range (Sichuan, China) using Landsat TM imagery acquired in 2001, geographical data, field surveys, and information acquired in previous researches. Results show that the habitat is separated by roads and rivers, as well as by human settlements and cropland areas, into four main habitat blocks. Overlapping these four habitat blocks with the current nature reserve network reveals that only 36% of the total habitat is protected within nature reserves. Thus, the current nature reserve network is failing to preserve essential habitat for dispersal and genetic exchange. In this study, five key areas and four linkage areas were identified and suggested as nature reserves and/or corridors. These areas, together with the six currently established nature reserves in the mountain range, will form a conservation unit for facilitating the exchange of giant panda individuals among previously isolated habitat blocks. Policies recently implemented by the Chinese government, including the Natural Forest Conservation Program (NFCP) and the Grain-to-Green Program (GTGP), could aid in the formation of such a conservation unit.     

四川短尾鼩的生境选择及对人为干扰的响应

2014年4-9月,通过铗夜法对12种不同生境内的四川短尾鼩种群数量进行了调查,依据捕获率的大小及生境的干扰程度分析四川短尾鼩的生境选择倾向。利用人工捕捉模拟种群干扰,分别在干扰1个月、2个月、3个月、4个月时间之后,监测荒草地、废弃梨树林、灌丛和绿化林4种代表性生境内四川短尾鼩的种群数量、年龄结构、性比的变化,进而分析四川短尾鼩对人为干扰的生态响应。结果显示：（1）四川短尾鼩在12种典型生境中,按捕获率的大小依次分为4个等级：绿化林＞废弃梨树林、景观林、荒草地、桉树林、蔬菜地、灌丛＞人居村落、废弃葡萄园＞竹林,葡萄园,油菜地;（2）四川短尾鼩的生境选择倾向为：异质性适中、适度干扰、竞争较低的生境＞异质性较低、干扰较高的生境（宜觅食、竞争弱）或异质性较高、干扰较低的生境（宜栖身、竞争弱）＞高竞争的生境＞异质性低或强烈干扰或二者兼有的生境。（3）干扰之初,所有生境中四川短尾鼩种群密度明显降低,干扰2个月之后其种群数量均可恢复到正常状态;干扰后性比平均值增加3.52%,怀孕率变化不显著;全部生境中,成体组比例平均降低1.71%,老年组减少7.53%;幼年组的比例平均增长2.33%,亚成体增加6.91%。幼体和亚成体比例的增加,使种群数量在一定时间内保持稳定增长。     

Land-use selection by dandelions in the Tokyo metropolitan area,Japan

Land use by native and introduced dandelion groups in man-made habitats was studied at 7090 survey points in the Tokyo metropolitan area, Japan, in order to clarify the replacement phenomenon occurring among dandelions. In the center of Tokyo, where the native group was rare, the percentage occurrence of the introduced group was lower than in other regions, whereas in the outskirts of Tokyo, both groups showed much higher occurrence. Roadsides, vacant areas and urban land-use categories were significantly favorable for growth of the introduced group, whereas preserved or rural land use was more favorable for the native group. Seed fertility in the introduced group was more than 80%, and was independent of population size, whereas in the native group it was not as high, and for a small population was dependent on population size, being stable at about 70% in populations larger than 70 plants. Thus, both large populations and solitary plants in the introduced group appeared to act as seed sources, making it likely that the introduced group will spread increasingly through roadsides and urban land, which are becoming more widespread as a result of urbanization. It is feared that, unless deliberately retained, the amount of preserved or rural land which has fostered large populations of the native group will further decrease with urbanization and other forms of development, thus depleting the seed sources and reducing the population.     

40年岷山地区白河自然保护区川金丝猴的生境格局动态

好的生境质量是野生动物生存和繁衍的必备条件,生境质量的变化将对动物的生存产生深远影响,定量客观的评估生境变迁过程显得尤为必要。川金丝猴作为我国一级保护动物,评定其生境质量变化过程有利于制定有效的保护措施。3S技术的不断发展与广泛应用为研究川金丝猴生境格局的动态变化提供了有利的工具。以岷山白河自然保护区为例,利用陆地资源卫星的MSS/TM/OLI遥感影像,并基于专家知识的决策树分类方法对遥感影像进行分类,获取了5个时期的覆被类型空间分布图;根据NDVI与郁闭度的相关性获取了研究区郁闭度的时空变化信息。然后,通过对野外观测数据的数理统计与空间分析,获取了川金丝猴的生活习性特征,并结合AHP方法构建了川金丝猴生境质量的评价体系,对5个时期的生境质量进行了评价,最后定量分析了40年来川金丝猴的生境格局的动态变化趋势。研究表明,近40年来白河自然保护区内及周边的生境经历了由良好到不断恶化,再到逐渐恢复的过程,其中最适宜和适宜生境呈现先降低后逐渐升高的趋势,而不适宜和勉强适宜则表现为先增加后减小的趋势。1975—1982年时段内,各生境等级变化剧烈,尤以最适宜和不适宜等级变化显著,生境质量整体呈恶化趋势;1982—1994年,各生境等级变化剧烈程度较前一时期有所缓和,生境质量得到较大改善,呈良性发展趋势;1994—2003年时段内,研究区内生境质量进一步改善,环境恶化状况得到了缓解;2003—2014年时间段内整体质量改善的速度明显减缓,生境质量达到平衡状态。除1975—2014时段外,前4个时段的各综合变化指标呈现递减趋势,前期生境等级变化剧烈,后期趋缓。气候变化和人为干扰为导致生境变化的主要因素,其中20世纪80年代生境变化与气候变化关系密切,而20世纪90年代之后人为干扰因素明显增加。研究有助于理解气候变化与人为干扰背景下,川金丝猴生境格局时空变化特征,为野生濒危动物生境保护管理和政策制定提供科学依据。     

Nest-site habitat selection by Lesser Rheas ( Rhea pennata pennata ) in northwestern Patagonia, Argentina

Selection of nest-site habitat by a population of wild Lesser Rheas (Rhea pennata pennata) was studied in the northwestern Patagonia steppe, Argentina, during two reproductive seasons (2004/2005 and 2005/2006). Nest spatial distribution was compared with randomly selected points in the study area. Contrary to observations in other ratite species, nest distribution showed an aggregate pattern associated with “mallín” (meadow) areas, which are habitats of higher productivity in the Patagonia steppe. Moreover, similar to observations made on the Greater Rhea (Rhea americana), vegetation cover was higher in nest sites than in randomly selected sites, probably because higher vegetation provides concealment from predators and protection from the strong westerly winds that frequent in this region. Our results reinforce the importance of “mallín” areas for the reproduction and conservation of this threatened ratite species.     

小兴安岭通河林区原麝夏季对生境的选择

2004年8 ～ 9月,在通河县龙口林场采用样线样方法对原麝夏季生境的选择进行了研究。共设235个样方,其中原麝利用样方55 个,采用卡方（Chi-square） 统计进行显著性检验,结果表明原麝偏好利用针阔混交林,避免杂木林;倾向于选择离水源近、远离人为干扰的上坡位;一般喜欢有石砬子的山坡;对坡向的利用无选择性。对原麝利用样方和非利用样方进行比较,发现原麝生境具有海拔高、郁闭度小、食物丰富和坡度陡等特征。对各种生境因子的主成分分析表明,前6个特征值的累积贡献率达到73.30%,可以较好地反映原麝生境特征,根据载荷系数绝对值大小将原麝夏季生境选择影响因子分别命名为食物丰富度因子、植被因子、干扰因子、隐蔽度因子、地理因子和倒木因子。     

Seasonal shifts in habitat selection of a large herbivore and the influence of human activity

Failure to recognize factors contributing to variation in habitat models like resource selection functions (RSFs) can affect their application for projecting probabilities of occurrence, and thereby limit their relevance for conservation and management. We compared seasonal RSFs (2006–2008) for 16 adult female moose (Alces alces) with home ranges located in western Algonquin Provincial Park (APP), Ontario, Canada, to those of 14 adult females located in provincial Wildlife Management Unit (WMU) 49, 40 km west of the protected area. Wildlife and habitat management practices differed between regions: hunting was higher in WMU 49 compared to APP, and APP preserved large tracts of old growth forest rarely found in WMU 49. Seasonal RSFs projected expected similarities in moose resource use between regions (e.g., responses to wetlands and stands of eastern hemlock, Tsuga canadensis [in winter]); however, we also observed differences consistent with the hypothesis that animals, through effects of hunting, would shift habitat use seasonally and in response to roads. We further observed evidence of functional responses in habitat selection due to underlying differences in forestry practices (e.g., responses to stands of old-growth hemlock forest). Given the close proximity and shared biogeographic region between study areas, we believe that observed spatial dynamics in RSFs were ultimately reflective of divergent management strategies between areas and ensuing differences in predation and hunting mortality risk, and functional habitat.     

Where have all the weta gone? Results after two decades of transferring a threatened New Zealand giant weta, Deinacrida mahoenui

There have been numerous transfers of the large-bodied orthopteran, the Mahoenui giant weta (Family Anostostomatidae: Deinacrida mahoenui), over the past 19 years but there has been limited follow-up monitoring to ascertain establishment and breeding of transferred populations. Recent surveys carried out at all the locations where this weta were transferred, found weta at four of the seven transferred sites. The most important factor determining the success of past transfers is the absence of introduced mammalian predators, particularly rats, at a site. At two sites, Mahurangi Island Scenic Reserve and Warrenheip, weta appeared to be flourishing and have successfully established new populations in the absence of rats. If mammals are present at a site, the occurrence of dense prickly gorse to protect giant weta from predation is another important factor in their survival. Weta were found at very low densities (only single specimens were captured) at Mangaokewa Scenic Reserve and Tikikaru (private land) and it is likely their populations are not viable in the long term. Further efforts to establish Mahoenui giant weta populations should be in mammal-free sanctuaries containing native forest. More intensive post-transfer monitoring using radio-transmitters would enable better understanding of their behaviour after transfer. In addition, long-term regular monitoring of transferred populations is required, particularly those where the likelihood of rat re-invasion is high.     

厦门水域中华白海豚栖息地选择的初步研究

中华白海豚（Sousa chinensis）在中国水域主要包括3个种群,分别分布在珠江口（包括香港）、九龙江口（厦门水域）和北部湾广西沿岸水域,近年来在台湾西海岸和广东的雷州又陆续发现了新的种群（Wang et al．,2004;周开亚等,待发表资料）。该物种主要以中小种群分布于近岸浅水水域,易受各种人类活动的影响,如渔业捕捞、船舶航运、港口建设和水体污染等,其保护状况引起了人们的广泛关注。在1988年颁布的《中华人民共和国野生动物保护法》中,已将该物种列为国家一级保护动物。     

Climate warming over the past three decades has shortened rice growth duration in China and cultivar shifts have further accelerated the process for late rice

An extensive dataset on rice phenology in China, including 202 series broadly covering the past three decades (1980s–2000s), was compiled. From these data, we estimated the responses of growth duration length to temperature using a regression model based on the data with and without detrending. Regression coefficients derived from the detrended data reflect only the temperature effect, whereas those derived from data without detrending represent a combined effect of temperature and confounding cultivar shifts. Results indicate that the regression coefficients calculated from the data with and without detrending show an average shortening of the growth duration of 4.1–4.4 days for each additional increase in temperature over the full growth cycle. Using the detrended data, 95.0% of the data series exhibited a negative correlation between the growth duration length and temperature; this correlation was significant in 61.9% of all of the data series. We then compared the difference between the two regression coefficients calculated from data with and without detrending and found a significantly greater temperature sensitivity using the data without detrending (?2.9 days °C^?1) than that derived from the detrended data (?2.0 days °C^?1) in the period of emergence to heading for the late rice, producing a negative difference in temperature sensitivity (?0.9 days °C^?1). This implies that short‐duration cultivars were planted with increase in temperature and exacerbated the undesired phenological change. In contrast, positive differences were detected for the single (0.6 days °C^?1) and early rice (0.5 days °C^?1) over the full growth cycle, which might indicate that long‐duration cultivars were favoured with climate warming, but these differences were insignificant. In summary, our results suggest that a major, temperature induced change in the rice growth duration is underway in China and that using a short‐duration cultivar has been accelerating the process for late rice.     

Ontogenetic habitat shifts by Galaxias gracilis (Galaxiidae) between the littoral and limnetic zones of Lake Kanono, New Zealand

Synopsis Diel and spatial differences in distribution were determined for the larvae, juveniles, and adults of Galaxias gracilis (Galaxiidae) in a New Zealand dune lake during summer months. Larvae (mostly 10–25 mm TL) and juveniles (25–40 mm TL) inhabited shallow (0–3 m) waters of the limnetic zone and fed predominantly on two limnetic zooplankton species; Bosmina meridionalis and a calanoid copepod. At about 40 mm TL, fish moved from the limnetic to the littoral zone and expanded dietary breadth from two to over seven main prey species, including five species of littoral invertebrates. After reaching a size of about 60 mm TL, most fish moved back offshore to the deeper waters (5–15 m) of the limnetic zone during the day, moving back to the littoral zone at night to feed on invertebrates. The selection of different intra-lacustrine habitats by the various size groups of G. gracilis, and the movements between them, are interpreted as adaptive responses to the interaction between ontogenetic changes in feeding requirements and predation risk.     

Vegetation recovery and recent degradation in different karst landforms of southwest China over the past two decades using GEE satellite archives

Over the past two decades, eco-engineering has been recognized as an important restoration approach to promote vegetation regrowth and greenness in a widespread rocky desertification land of southwest China. However, it remains unclear of recovery patterns and dominating drivers in different types of karst landforms. Here we use multi-satellite archives based on Google Earth Engine (GEE) to reveal the rapid greening process although encountered severe drought, especially in Karst Peak-Cluster Depression (+0.0035y⁻¹) and Karst Trough Valley (+0.0035y⁻¹) influenced by subtropical monsoon climate and afforestation endeavor, while degradation happened recently at non-karst areas of west highland in Karst Fault Basin (−0.0043y⁻¹ since 2006) and Karst Plateau (−0.0039y⁻¹ since 2014) influenced by decreasing rainfall. Afforestation project and sloping land conversion program is found to play crucial part in explaining a large part of the greening trend in Peak-Cluster Depression and Trough Valley but not in other landforms, suggesting that geomorphic heterogeneity should be further considered in restoration implementation and vegetation assessment, in conjunction with climate change and anthropogenic factors. Our study provides a helpful perspective for karst conservation priorities of various rocky desertification region ecosystems.     

Fish assemblage in the Pearl River Estuary: Spatial‐seasonal variation,environmental influence and trends over the past three decades

The Pearl River Estuary is the largest estuary in South China and plays a considerable role in the local fisheries economy, yet little is known about the current state of fish assemblage in this ecosystem. To quantify spatial‐seasonal variations, environmental influences, and trends over the past three decades of the fish assemblage in the Pearl River Estuary, we sampled 11 sites seasonally from December 2013 to September 2016. Throughout the study, 285 species from 88 families and 195 genera were collected. There were obvious spatial and seasonal variations of the fish assemblage in terms of the dominant species, species richness, and composition of ecological types. Mouth distance, NH₄⁺ N, chlorophyll‐a, flow, DO, salinity and water transparency were the main variables influencing the spatial‐temporal dynamic of fishes within the estuarine systems. Compared with the record of 330 species in the 1980s, the number of fish species in the Pearl River Estuary has declined by 45 fish species. The Jaccard's similarity of fish composition between the historical investigation (the 1980's) and the present investigation (2013–2016) was 0.62, with 95 species undiscovered and 50 species increased in the present study compared to the 1980s, indicating the assemblage structure has obviously changed. However, in term of ecological guilds, there was no significant difference in the composition of all the selected ecological traits between these two periods. Anthropogenic activities including overfishing, introducing alien fish, dam construction and pollution were considered the main disturbance on fish composition over the past three decades. We conclude that there existed pronounced spatiotemporal changes of fish assemblages, which arises from the compounding effects of environmental factors and anthropogenic activities. These findings are beneficial to understanding and developing suitable conservation strategies for the management and protection of fish resources in the Pearl River Estuary.