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Data from: Frost maintains forests and grasslands as alternate states in a montane tropical forest-grassland mosaic; but alien tree invasion and warming can disrupt this balance
- 负责人：
- DOI：
- doi:10.5061/dryad.4n7n883
- 摘要：
- 1. Forest-grassland mosaics, with abrupt boundaries between the two vegetation types, occur across the globe. Fire and herbivory are widely considered primary drivers that maintain these mosaics by limiting tree establishment in grasslands, while edaphic factors and frosts are generally considered to be secondary factors that reinforce these effects. However, the relative importance of these drivers likely varies across systems. In particular, although frost is known to occur in many montane tropical mosaics, experimental evidence for its role as a driving factor is limited. 2. We used replicated in-situ transplant and warming experiments to examine the role of microclimate (frost and freezing temperatures) and soil in influencing germination and seedling survival of both native forest trees and alien invasive Acacia trees in grasslands of a tropical montane forest-grassland mosaic in the Western Ghats of southern India. 3. Seed germination of both native and alien tree species was higher in grasslands regard-less of soil type, indicating that germination was not the limiting stage to tree establishment. However, irrespective of soil type, native seedlings in grasslands incurred high mortality fol-lowing winter frosts and freezing temperatures relative to native seedlings in adjoining forests where freezing temperatures did not occur. Seedling survival through the tropical winter was thus a primary limitation to native tree establishment in grasslands. In contrast, alien Acacia seedlings in grasslands incurred much lower levels of winter mortality. Experimental night-time warming in grasslands significantly enhanced over-winter survival of all tree seedlings, but increases in recruitment were much greater for alien Acacia than for native tree seedlings. 4. Synthesis: Our results provide evidence for a primary role for frost and freezing temperatures in limiting tree establishment in grasslands of this tropical forest-grassland mosaic. Future increases in temperature are likely to release trees from this limitation and favour tree expansion into grasslands, with rates of expansion of non-native Acacia likely to be much greater than that of native trees. We suggest that studies of frost limitation to plant establishment are needed across a range of tropical ecosystems to re-evaluate the general importance of frost as a driver of vegetation transitions in the tropics.
Tree Shelterbelts as an Element to Improve Water Resource Management in Central Asia
- 负责人：
- Thevs, Niels
- 关键词：
- DOI：
- doi:10.7910/dvn/0kkj09
- 摘要：
- ainst the background of current and increasing competition for water\u2014e.g., through reduced river runoffs in the course of climate change\u2014
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: Seasonal and annual differences in the foraging ecology of two gull species breeding in sympatry and their use of fishery discards
- 负责人：
- Calado, Joana G.
- DOI：
- doi:10.5061/dryad.m8t2k
- 摘要：
- s the yellow-legged gull showed a broader isotopic niche width than Audouin’s gull in 2013, and in 2014 the two gull species exhibited different isotopic niche
Data from: The effects of warming and nitrogen addition on ecosystem respiration in a Tibetan alpine meadow: the significance of winter warming
- 负责人：
- 关键词：
- DOI：
- doi:10.5061/dryad.nq82081
- 摘要：
- antly decreased aboveground biomass under no N addition. YW significantly decreased soil inorganic N, and WW decreased it in 2013 and 2014 under no N, and WW
GBIF Occurrence Download
- 负责人：
- DOI：
- doi:10.15468/dl.qmy74a
- 摘要：
- ) - Great Grey Shrike Count 2013-2014. 5530 records from iNaturalist Research-grade Observations. 75 records from Aranzadi Ringing Scheme (bird ring
GBIF Occurrence Download
- 负责人：
- DOI：
- doi:10.15468/dl.usnjuk
- 摘要：
- . Inventario Nacional de Biodiversidad 2007, Mamíferos. 273 records from Loup 2013 présence régulière communale (réseau Loup-Lynx ONCFS). 212 records from Loup
Millennium Village Impact Evaluation in Northern Ghana, 2012-2016: Special Licence Access;;Millennium Village Impact Evaluation in Northern Ghana, 2012-;;MVP; SADA-North Ghana Household Survey
- 负责人：
- 关键词：
- DOI：
- doi:10.5255/ukda-sn-7734-4
- 摘要：
- Years 0, 1, 2 and 3 of the study, conducted in 2012, 2013, 2014 and 2015 respectively.<br> <br> The site is located in Savannah Accelerated
Data from: Postpartum family planning integration with maternal, newborn, and child health services: a cross-sectional analysis of client flow patterns in India and Kenya
- 负责人：
- DOI：
- doi:10.5061/dryad.11313
- 摘要：
- : PPFP/postpartum intrauterine device—Bihar, India (2012–2013); Jharkhand, India (2010–2014); Embu, Kenya (2008–2012). Maternal, infant, and young child
Rift Valley fever virus seroprevalence data from people involved in a cross-sectional survey in Tana River and Garissa counties, Kenya (December 2013
- 负责人：
- Bett, Bernard;;Environmental Information Data Centre
- 关键词：
- Kenya Tana River Garissa Dynamic Drivers of Disease in Africa Consortium (DDDAC) Ecosystem Services for Poverty Alleviation (ESPA) Rift Valley Fever (RVF) seroprevalence serum
- DOI：
- doi:10.5285/8a668a4f-3526-4443-9e77-cea67f04ca19
- 摘要：
- riverine areas along River Tana in Tana River and Garissa counties, Kenya. Field surveys were implemented in December 2013 to February 2014 and laboratory
