Distance from available surface water of mammals in Ruaha National Park

In Africa, burgeoning human populations promote agricultural expansion and the associated demand for water. Water abstraction for agriculture from perennial rivers can be detrimental for wildlife, particularly when it reduces water availability in protected areas. Ruaha National Park (Ruaha NP) in southern Tanzania, one of the largest parks in Africa, contains important wildlife populations, including rare and endangered species. The Great Ruaha River (GRR) is the main dry-season water source for wildlife in the Park. Water offtake from this river for large-scale irrigation and livestock production up-stream of the Park has caused large expanses of this formerly perennial river within the Park to dry out during the dry season. The dry season distribution of a species in relation to surface water is considered an indicator of its dependence on water and ability to cope with the loss of surface water. We investigated how diminishing surface water availability during three dry seasons (201..., The study was conducted during three dry seasons (2011–2013) within Ruaha NP in central Tanzania, which is located at the transition between the East African Acacia-Commiphora zone and the southern African Brachystegia miombo zone (Barnes 1983).
Counts of individuals of each species sighted along 10 ground transects that used an existing game viewing tract were conducted at intervals of approximately 14 days from June to October and once in November during the dry seasons of 2011, 2012 and 2013; thus each transect was surveyed 11 times per year. To visualize how the progress of the dry season was associated with changes in the distribution of species in the study area, transect data were divided into early (June-Aug, each transect surveyed 6 times) and late dry season (Sept-Nov, each transect surveyed 5 times). Transects were approximately 20 km (mean transect length 19,880 m ± 115.3 m [standard error of mean, S.E.M.]) in length. Five transects were alongside the GRR (A transects 6, 7, ..., , # Distance from Available Surface Water of Mammals in Ruaha National Park

The study was conducted during three dry seasons (2011-2013) within Ruaha NP in central Tanzania, which is located at the transition between the East African *Acacia*-*Commiphora* zone and the southern African *Brachystegia* miombo zone (Barnes 1983).

Counts of individuals of each species sighted along 10 ground transects that used an existing game viewing tract were conducted at intervals of approximately 14 days from June to October and once in November during the dry seasons of 2011, 2012, and 2013; thus each transect was surveyed 11 times per year.

To analyze whether herbivores change their location in relation to the location of surface water, which shifts spatially during the dry season due to evaporation and the digging of water holes by wildlife, we calculated the Euclidean distances (m) from the species’ GPS location to the GPS location of the nearest surface water in the respective sampling week.

T...

在非洲，快速增长的人口推动了农业扩张，同时催生了与之相伴的水资源需求。从常年河流抽取农业用水会对野生生物造成不利影响，尤其是当该行为降低了保护区内的水资源可获得性时。坦桑尼亚南部的鲁阿哈国家公园（Ruaha National Park, Ruaha NP）是非洲规模最大的保护区之一，园内栖息着大量野生生物种群，包括珍稀濒危物种。大鲁阿哈河（Great Ruaha River, GRR）是该公园内野生生物的主要旱季水源。在该公园上游区域，为开展大规模灌溉与畜牧生产而从该河取水的行为，已导致园内大片原本常年性的河道在旱季彻底干涸。物种在旱季的分布与地表水的关联情况，被视为衡量其对水资源依赖程度以及应对地表水流失能力的指标。我们探究了在三个旱季（201……）中，地表水可获得性不断下降对……的影响。

本研究于2011至2013年的三个旱季在坦桑尼亚中部的鲁阿哈国家公园开展，该公园地处东非*金合欢属*-*没药属*群落区与南非*短盖豆属*米翁博群落区的过渡地带（Barnes 1983）。

本研究依托现有野生动物观赏步道，沿10条地面样线开展目击调查，记录沿途所见各物种的个体数量。2011、2012及2013年的旱季期间，调查于6月至10月每约14天开展1次，11月追加1次，因此每条样线每年共接受11次调查。

为厘清旱季进程与研究区内物种分布变化的关联，我们将样线调查数据划分为旱季早期（6月至8月，每条样线共调查6次）与旱季晚期（9月至11月，每条样线共调查5次）两组。

样线总长约20千米（样线平均长度为19880米±115.3米[均值标准误，standard error of mean, S.E.M.]），其中5条样线紧邻大鲁阿哈河（GRR）（A样线6、7……）。

# 鲁阿哈国家公园内哺乳动物与可利用地表水的距离

本研究于2011至2013年的三个旱季在坦桑尼亚中部的鲁阿哈国家公园开展，该公园地处东非*金合欢属*-*没药属*群落区与南非*短盖豆属*米翁博群落区的过渡地带（Barnes 1983）。

本研究依托现有野生动物观赏步道，沿10条地面样线开展目击调查，记录沿途所见各物种的个体数量。2011、2012及2013年的旱季期间，调查于6月至10月每约14天开展1次，11月追加1次，因此每条样线每年共接受11次调查。

为分析草食动物是否会根据地表水的位置调整自身活动位置——由于蒸发作用与野生生物挖掘水坑，地表水的空间分布会随旱季进程发生变化——我们计算了各采样周内，物种全球定位系统（Global Positioning System, GPS）定位点到最近地表水GPS定位点的欧氏距离（Euclidean distances，单位：米）。

T……