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Djamde Wildlife Reserve in Togo: diversity of woody species
- 负责人：
- Koudjo AKPENE;;Kotchikpa Okoumassou;;Tchagou Awitazi;;Kotchikpa Okoumassou
- 关键词：
- DOI：
- doi:10.15468/ugkanx
- 摘要：
- and these forests have been recognized to harbor a significant proportion of global biodiversity (Myers et al 2000; Baraloto et al 2013) and also provide
Data from: Lianas reduce community-level canopy tree reproduction in a Panamanian forest
- 负责人：
- Schnitzer, Stefan
- 关键词：
- Plant–plant interactions Determinants of plant community diversity and structure community ecology competition dispersal limitation liana cutting tropical forests
- DOI：
- doi:10.5061/dryad.m2471
- 摘要：
- ) and surveyed understorey tree reproduction in 2012, canopy tree and palm reproduction in 2013, and a second census of all plants in 2016. We found tha
Data from: A century of conservation: the ongoing recovery of Svalbard reindeer
- 负责人：
- DOI：
- doi:10.5061/dryad.7351kt1
- 摘要：
- Several caribou and reindeer (Rangifer tarandus) populations have experienced recent population declines, often attributed to anthropogenic stressors such as harvesting, landscape fragmentation, and climate change. Svalbard reindeer (R. t. platyrhynchus), the wild reindeer subspecies endemic to the high-Arctic Svalbard archipelago, was protected in 1925, after most subpopulations had been eradicated by harvest. Although direct pressure from harvest has ceased, indirect anthropogenic stressors from environmental changes have increased in this climate change hot spot. An assessment of the current distribution and abundance is therefore urgently needed. We combined distance sampling (300 km transects, n = 489 reindeer groups) and total counts (1,350 km2, n = 1,349 groups) to estimate the Svalbard reindeer distribution and abundance across its entire range, which we compared with historical data from the literature and radiocarbon-dated bones. Reindeer have now recolonized nearly all non-glaciated land (i.e., areas occupied prior to human presence), and their spatial variation in abundance reflects vegetation productivity. Independent of vegetation productivity, however, recently recolonized areas have lower reindeer densities than areas not subject to past extirpation. This suggests that recovery from past overharvesting is still in progress. These incompletely recovered areas are potential targets for increased monitoring frequency and maintaining strict conservation to follow the Svalbard management goal (i.e., virtually untouched wilderness areas). Because of such ongoing recolonization, possibly combined with vegetation greening effects of recent warming, our status estimate of Svalbard reindeer abundance (22,435 [95% CI = 21,452–23,425]) is more than twice a previous estimate based on opportunistic counts. Thus, although our study demonstrates the successful outcome of strict harvesting control implemented a century ago, current and future population trajectories are likely shaped by climate change.
Data from: Yellow perch genetic structure and habitat use among connected habitats in eastern Lake Michigan
- 负责人：
- Chorak, Gregory
- 关键词：
- DOI：
- doi:10.5061/dryad.2444ck7
- 摘要：
- , and autumn and two nearshore sites in Lake Michigan (spring and autumn) during 2015-2016 and supplemented our sampling with fish collected in 2013
Data from: Rapid change in host specificity in a field population of the biological control organism Pasteuria penetrans
- 负责人：
- Gibson, Amanda
- 关键词：
- Biological control Coevolution Crop rotation Evolution of specificity peanut root-knot nematode
- DOI：
- doi:10.5061/dryad.0pv6570
- 摘要：
- Pasteuria penetrans. Pasteuria penetrans is an obligate parasite of the plant parasitic nematodes Meloidogyne spp., which are major agricultural pests. From 2013 thr
Data from: Spatial modeling improves understanding patterns of invasive species defoliation by a biocontrol herbivore
- 负责人：
- DOI：
- doi:10.5061/dryad.2ts54jj
- 摘要：
- ome an inseparable part of Tamarix-dominated river systems in the southwest. Between 2013 and 2016 tamarisk dieback was assessed at 79 sites across Grand County, Utah
Data from: Urgent-start peritoneal dialysis and hemodialysis in ESRD patients: complications and outcomes
- 负责人：
- DOI：
- doi:10.5061/dryad.20h3k
- 摘要：
- 2013 to December 2014 were included. Patients were grouped according to their dialysis modality (PD and HD). Each patient was followed for at least 30
Data from: Direct effects of a non-native invader erode native plant fitness in the forest understory
- 负责人：
- DOI：
- doi:10.5061/dryad.4k7d5n7
- 摘要：
- 1. The direct role of non-native plant invaders in driving negative population- and community-level processes of native species has been recently questioned. Addressing this controversy requires determining quantitatively if invaders negatively affect native population fitness. Because the invasion of non-natives often coincides with other anthropogenic stressors, experiments that partition the putative impact of non-natives from other known stressors and assess their potential synergies are required. While many studies have examined the effects of non-natives on components of native plant performance, studies that decompose the net fitness effects of non-natives from other anthropogenic stressors on population growth rate are lacking. 2. We used six years of detailed demographic data to parameterize a size-dependent integral projection model to examine the individual and combined effects of an allelochemical-producing invader (Alliaria petiolata) and an overabundant ungulate herbivore (Odocoileus virginianus) on the population dynamics of an understory perennial (Trillium erectum). 3. We show that Alliaria consistently and negatively affects the population dynamics of Trillium. Specifically, this invader reduces native population growth rate and alters the size distribution of the population at equilibrium. Alliaria also works in concert with the known negative impacts of overabundant white-tailed deer, illustrating the additive effects of anthropogenic stressors on native plant dynamics. 4. Synthesis. Alliaria’s effects on vital rates differed in magnitude and sign across the native’s lifecycle, highlighting the importance of detailed demographic analyses. Globally, our study provides novel empirical support for the claim that non-native invasive species can significantly and directly reduce the fitness of native plants.
Data from: Modeling seasonal surface temperature variations in secondary tropical dry forests
- 负责人：
- DOI：
- doi:10.5061/dryad.0bq52
- 摘要：
- time series from July 2013 to July 2016 using a radiative transfer equation (RTE) algorithm. We further related the LST time series to seven vegetation indices
Data from: Rediscovering a forgotten canid species
- 负责人：
- DOI：
- doi:10.5061/dryad.63rb4
- 摘要：
- Background: The African wolf, for which we herein recognise Canis lupaster Hemprich and Ehrenberg, 1832 (Symbolae Physicae quae ex Itinere Africam Borealem er Asoam Occidentalem Decas Secunda. Berlin, 1833) as the valid species name (we consider the older name Canis anthus Cuvier, 1820 [Le Chacal de Sénégal, Femelle. In: Geoffroy St.-Hilaire E, Cuvier F, editors. Histoire Naturelle des Mammifères Paris, A. Belin, 1820] a nomen dubium), is a medium-sized canid with wolf-like characters. Because of phenotypic similarity, specimens of African wolf have long been assigned to golden jackal (Canis aureus Linnaeus, 1758 [Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I. Editio decima, reformata, 1758]). Results: Here we provide, through rigorous morphological analysis, a species description for this taxonomically overlooked species. Through molecular sequencing we assess its distribution in Africa, which remains uncertain due to confusion regarding possible co-occurrence with the Eurasian golden jackal. Canis lupaster differs from all other Canis spp. including the golden jackal in its cranial morphology, while phylogenetically it shows close affinity to the Holarctic grey wolf (Canis lupus Linnaeus, 1758 [Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I. Editio decima, reformata, 1758]). All sequences generated during this study clustered with African wolf specimens, consistent with previous data for the species. Conclusions: We suggest that the estimated current geographic range of golden jackal in Africa represents the African wolf range. Further research is needed in eastern Egypt, where a hybrid zone between Eurasian golden jackal and African wolf may exist. Our results highlight the need for improved studies of geographic range and population surveys for the taxon, which is classified as ‘least concern’ by the IUCN due to its erroneous identification as golden jackal. As a species exclusively distributed in Africa, investigations of the biology and threats to African wolf are needed.
