Alien species as a driver of recent extinctions

We assessed the prevalence of alien species as a driver of recent extinctions in five major taxa (plants, amphibians, reptiles, birds and mammals), using data from the IUCN Red List. Our results show that alien species are the second most common threat associated with species that have gone completely extinct from these taxa since AD 1500. Aliens are the most common threat associated with extinctions in three of the five taxa analysed, and for vertebrate extinctions overall.     

Increasing arboreality with altitude: a novel biogeographic dimension

Biodiversity is spatially organized by climatic gradients across elevation and latitude. But do other gradients exist that might drive biogeographic patterns? Here, we show that rainforest''s vertical strata provide climatic gradients much steeper than those offered by elevation and latitude, and biodiversity of arboreal species is organized along this gradient. In Philippine and Singaporean rainforests, we demonstrate that rainforest frogs tend to shift up in the rainforest strata as altitude increases. Moreover, a Philippine-wide dataset of frog distributions shows that frog assemblages become increasingly arboreal at higher elevations. Thus, increased arboreality with elevation at broad biogeographic scales mirrors patterns we observed at local scales. Our proposed ‘arboreality hypothesis’ suggests that the ability to exploit arboreal habitats confers the potential for larger geographical distributions because species can shift their location in the rainforest strata to compensate for shifts in temperature associated with elevation and latitude. This novel finding may help explain patterns of species richness and abundance wherever vegetation produces a vertical microclimatic gradient. Our results further suggest that global warming will ‘flatten’ the biodiversity in rainforests by pushing arboreal species towards the cooler and wetter ground. This ‘flattening’ could potentially have serious impacts on forest functioning and species survival.     

Biodiversity hanging by a thread: the importance of fungal litter-trapping systems in tropical rainforests

The exceptionally high species richness of arthropods in tropical rainforests hinges on the complexity of the forest itself: that is, on features such as the high plant diversity, the layered nature of the canopy and the abundance and the diversity of epiphytes and litter. We here report on one important, but almost completely neglected, piece of this complex jigsaw-the intricate network of rhizomorph-forming fungi that ramify through the vegetation of the lower canopy and intercept falling leaf litter. We show that this litter-trapping network is abundant and intercepts substantial amounts of litter (257.3 kg ha(-1)): this exceeds the amount of material recorded in any other rainforest litter-trapping system. Experimental removal of this fungal network resulted in a dramatic reduction in both the abundance (decreased by 70.2 ± 4.1%) and morphospecies richness (decreased by 57.4 ± 5.1%) of arthropods. Since the lower canopy levels can contain the highest densities of arthropods, the proportion of the rainforest fauna dependent on the fungal networks is likely to be substantial. Fungal litter-trapping systems are therefore a crucial component of habitat complexity, providing a vital resource that contributes significantly to rainforest biodiversity.     

利用红外相机技术对安徽省鹞落坪国家级自然保护区大中型兽类及林下鸟类的调查

鹞落坪国家级自然保护区位于大别山脉南麓的核心地带。2014-2017年, 作者采用红外相机技术对鹞落坪国家级自然保护区的大中型兽类及林下鸟类进行调查。研究共布设了72个相机位点, 累计完成16,658个相机工作日, 获得独立有效照片2,142张, 共记录野生兽类9种、鸟类15种, 隶属8目15科。包括国家一级重点保护野生动物1种, 即安徽麝(Moschus anhuiensis), 国家二级重点保护野生动物2种, 分别是勺鸡(Pucrasia macrolopha)和白冠长尾雉(Syrmaticus reevesii)。相对多度排名前五的兽类分别为小麂(Muntiacus reevesi)、野猪(Sus scrofa)、赤腹松鼠(Callosciurus erythraeus)、猪獾(Arctonyx collaris)和岩松鼠(Sciurotamias davidianus)。相对多度排名前五的鸟类为白冠长尾雉、勺鸡、松鸦(Garrulus glandarius)、灰背鸫(Turdus hortulorum)、红嘴蓝鹊(Urocissa erythroryncha)。此外红外相机还拍摄到大量人类活动照片, 表明当地人类活动较为严重, 应加强管理。本研究初步了解了保护区内大中型兽类和林下鸟类群落信息及人类活动的干扰情况, 为保护区未来的保护和管理工作提供了数据基础。     

基于红外相机技术调查佛坪国家级自然保护区兽类和鸟类多样性

2015年1月至2017年12月, 在陕西佛坪国家级自然保护区57条巡护样线上布设130台红外相机, 对兽类和鸟类多样性进行调查。累计相机工作日101,220天, 共捕获独立有效事件36,100次, 其中兽类独立照片30,563张, 鸟类3,244张。共记录到野生兽类6目15科29种, 相对多度较高的前5个物种依次是秦岭羚牛(Budorcas bedfordi, RAI = 11.53)、野猪(Sus scrofa, RAI = 4.80)、小麂(Muntiacus reevesi, RAI = 4.35)、大熊猫(Ailuropoda melanoleuca, RAI = 1.81)和中国豪猪(Hystrix hodgsoni, RAI = 1.13)。共记录到鸟类8目14科54种, 相对多度最高的前5个物种依次是红腹锦鸡(Chrysolophus pictus, RAI = 0.97)、红腹角雉(Tragopan temminckii, RAI = 0.74)、紫啸鸫(Myophonus caeruleus, RAI = 0.51)、红嘴蓝鹊(Urocissa erythrorhyncha, RAI = 0.13)、黑领噪鹛(Garrulax pectoralis, RAI = 0.12)。保护区鸟类新记录4种, 包括白眉地鸫(Geokichla sibirica)、白眉鸫(Turdus obscurus)、长尾地鸫(Zoothera dixoni)和灰脸鵟鹰(Butastur indicus); 保护区兽类新记录1种, 为亚洲狗獾(Meles leucurus)。本研究利用红外相机技术客观记录了佛坪国家级自然保护区兽类和鸟类的本底情况, 不仅初步了解了保护区内的野生动物分布, 而且更新了保护区鸟类资源数据库, 为保护区未来的保护和管理工作提供了数据基础。     

基于红外相机对四川千佛山国家级自然保护区兽类及鸟类多样性的初步调查

生物多样性编目是保护区管理和科研的基础性工作。2016年7月—2017年6月,利用红外相机调查四川千佛山国家级自然保护区内的兽类和鸟类多样性。调查期内共布设20个监测位点,累计3 333个相机监测日,获得照片2 355张,视频1 867段,独立有效记录共计436次,共鉴定出兽类4目10科17种和鸟类2目8科18种,其中,国家Ⅰ级重点保护野生动物3种,国家Ⅱ级重点保护野生动物8种,被世界自然保护联盟(IUCN)红色名录列为濒危(EN) 1种、易危(VU) 5种和近危(NT) 1种。调查中发现岷山山系的新记录1种:灰翅鸫Turdus boulboul。兽类相对丰富度指数(RAI)从高到低依次是川金丝猴Rhinopithecus roxellanae(2. 37)、毛冠鹿Elaphodus cephalophus(1. 83)、野猪Sus scrofa(1. 17)、岩松鼠Sciurotamias davidianus(1. 02)、赤麂Muntiacus vaginalis(0. 21); RAI最高的鸟类是鸡形目Galliformes,如红腹锦鸡Chrysolophus pictus(3. 21)和红腹角雉Tragopan temminckii(1. 05),其次是雀形目Passeriformes噪鹛科Leiothrichidae。本研究获得的兽类和鸟类数据是保护区生物多样性本底数据的有效补充,红外相机的持续监测将有利于保护区的长期监测和保护管理。