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Predicting Richness of Native, Rare, and Exotic Plants in Response to Habitat and Disturbance Variables across a Variegated Landscape 总被引:8,自引:0,他引:8
Species richness of native, rare native, and exotic understorey plants was recorded at 120 sites in temperate grassy vegetation in New South Wales. Linear models were used to predict the effects of environment and disturbance on the richness of each of these groups. Total native species and rare native species showed similar responses, with richness declining on sites of increasing natural fertility of parent material as well as declining under conditions of water enrichment (resulting from human-induced changes in drainage characteristics, leading to increased run-off), severe livestock grazing, and soil disturbance. The response of rare native species to water enrichment, however, was significantly greater than that of all native species. Exotic species richness varied in reverse to that of native species with positive responses to water enrichment and soil disturbance. The contrasting behaviors are attributed to differences in the evolutionary history of native and exotic assemblages and their resulting preadaptations to a landscape recently subjected to agricultural settlement. It would appear that for exogenous disturbances, the intermediate disturbance hypothesis is not supported by our data. In the sampled region, pastures represent the major land-use in terms of area, but have relatively low densities of native and rare species compared with more lightly grazed areas. However, their management is considered to be essential to the maintenance of diversity on a regional scale. 相似文献
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Planetary Stewardship in an Urbanizing World: Beyond City Limits 总被引:1,自引:0,他引:1
Sybil P. Seitzinger Uno Svedin Carole L. Crumley Will Steffen Saiful Arif Abdullah Christine Alfsen Wendy J. Broadgate Frank Biermann Ninad R. Bondre John A. Dearing Lisa Deutsch Shobhakar Dhakal Thomas Elmqvist Neda Farahbakhshazad Owen Gaffney Helmut Haberl Sandra Lavorel Cheikh Mbow Anthony J. McMichael Joao M. F. deMorais Per Olsson Patricia Fernanda Pinho Karen C. Seto Paul Sinclair Mark Stafford Smith Lorraine Sugar 《Ambio》2012,41(8):787-794
Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security. 相似文献
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Vulnerability of land systems to fire: Interactions among humans,climate, the atmosphere,and ecosystems 总被引:3,自引:0,他引:3
Sandra Lavorel Mike D. Flannigan Eric F. Lambin Mary C. Scholes 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):33-53
Fires are critical elements in the Earth System, linking climate, humans, and vegetation. With 200–500 Mha burnt annually,
fire disturbs a greater area over a wider variety of biomes than any other natural disturbance. Fire ignition, propagation,
and impacts depend on the interactions among climate, vegetation structure, and land use on local to regional scales. Therefore,
fires and their effects on terrestrial ecosystems are highly sensitive to global change. Fires can cause dramatic changes
in the structure and functioning of ecosystems. They have significant impacts on the atmosphere and biogeochemical cycles.
By contributing significantly to greenhouse gas (e.g., with the release of 1.7–4.1 Pg of carbon per year) and aerosol emissions,
and modifying surface properties, they affect not only vegetation but also climate. Fires also modify the provision of a variety
of ecosystem services such as carbon sequestration, soil fertility, grazing value, biodiversity, and tourism, and can hence
trigger land use change. Fires must therefore be included in global and regional assessments of vulnerability to global change.
Fundamental understanding of vulnerability of land systems to fire is required to advise management and policy. Assessing
regional vulnerabilities resulting from biophysical and human consequences of changed fire regimes under global change scenarios
requires an integrated approach. Here we present a generic conceptual framework for such integrated, multidisciplinary studies.
The framework is structured around three interacting (partially nested) subsystems whose contribute to vulnerability. The
first subsystem describes the controls on fire regimes (exposure). A first feedback subsystem links fire regimes to atmospheric
and climate dynamics within the Earth System (sensitivity), while the second feedback subsystem links changes in fire regimes
to changes in the provision of ecological services and to their consequences for human systems (adaptability). We then briefly
illustrate how the framework can be applied to two regional cases with contrasting ecological and human context: boreal forests
of northern America and African savannahs. 相似文献
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Matthew J. Colloff Sandra Lavorel Lorrae E. van Kerkhoff Carina A. Wyborn Ioan Fazey Russell Gorddard Georgina M. Mace Wendy B. Foden Michael Dunlop I. Colin Prentice John Crowley Paul Leadley Patrick Degeorges 《Conservation biology》2017,31(5):1008-1017
We examine issues to consider when reframing conservation science and practice in the context of global change. New framings of the links between ecosystems and society are emerging that are changing peoples’ values and expectations of nature, resulting in plural perspectives on conservation. Reframing conservation for global change can thus be regarded as a stage in the evolving relationship between people and nature rather than some recent trend. New models of how conservation links with transformative adaptation include how decision contexts for conservation can be reframed and integrated with an adaptation pathways approach to create new options for global‐change‐ready conservation. New relationships for conservation science and governance include coproduction of knowledge that supports social learning. New processes for implementing adaptation for conservation outcomes include deliberate practices used to develop new strategies, shift world views, work with conflict, address power and intergenerational equity in decisions, and build consciousness and creativity that empower agents to act. We argue that reframing conservation for global change requires scientists and practitioners to implement approaches unconstrained by discipline and sectoral boundaries, geopolitical polarities, or technical problematization. We consider a stronger focus on inclusive creation of knowledge and the interaction of this knowledge with societal values and rules is likely to result in conservation science and practice that meets the challenges of a postnormal world. 相似文献
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Lavorel Sandra Grigulis Karl Leitinger Georg Kohler Marina Schirpke Uta Tappeiner Ulrike 《Regional Environmental Change》2017,17(8):2251-2264
Regional Environmental Change - Land use and spatial patterns which reflect social-ecological legacies control ecosystem service (ES) supply. Yet, temporal changes in ES bundles associated with... 相似文献
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P��n��lope Lamarque Ulrike Tappeiner Catherine Turner Melanie Steinbacher Richard D. Bardgett Ute Szukics Markus Schermer Sandra Lavorel 《Regional Environmental Change》2011,11(4):791-804
The concept of ecosystem services is increasingly being used by scientists and policy makers. However, most studies in this area have focussed on factors that regulate ecosystem functions (i.e. the potential to deliver ecosystem services) or the supply of ecosystem services. In contrast, demand for ecosystem services (i.e. the needs of beneficiaries) or understanding of the concept and the relative ranking of different ecosystem services by beneficiaries has received limited attention. The aim of this study was to identify in three European mountain regions the ecosystem services of grassland that different stakeholders identify (which ecosystem services for whom), the relative rankings of these ecosystem services, and how stakeholders perceive the provision of these ecosystem services to be related to agricultural activities. We found differences: (1) between farmers?? perceptions of ecosystem services across regions and (2) within regions, between knowledge of ecosystem services gained by regional experts through education and farmers?? local field-based knowledge. Nevertheless, we identified a common set of ecosystem services that were considered important by stakeholders across the three regions, including soil stability, water quantity and quality, forage quality, conservation of botanical diversity, aesthetics and recreation (for regional experts), and forage quantity and aesthetic (for local farmers). We observed two contrasting stakeholder representations of the effects of agricultural management on ecosystem services delivery, one negative and the other positive (considering low to medium management intensity). These representations were determined by stakeholders?? perceptions of the relationships between soil fertility and biodiversity. Overall, differences in perceptions highlighted in this study show that practitioners, policy makers and researchers should be more explicit in their uses of the ecosystem services concept in order to be correctly understood and to foster improved communication among stakeholders. 相似文献
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Plant-trait-based modeling assessment of ecosystem-service sensitivity to land-use change 总被引:1,自引:0,他引:1
Fabien Quétier Sandra Lavorel Wilfried Thuiller Ian Davies 《Ecological applications》2007,17(8):2377-2386
Evidence is accumulating that the continued provision of essential ecosystem services is vulnerable to land-use change. Yet, we lack a strong scientific basis for this vulnerability as the processes that drive ecosystem-service delivery often remain unclear. In this paper, we use plant traits to assess ecosystem-service sensitivity to land-use change in subalpine grasslands. We use a trait-based plant classification (plant functional types, PFTs) in a landscape modeling platform to model community dynamics under contrasting but internally consistent land-use change scenarios. We then use predictive models of relevant ecosystem attributes, based on quantitative plant traits, to make projections of ecosystem-service delivery. We show that plant traits and PFTs are effective predictors of relevant ecosystem attributes for a range of ecosystem services including provisioning (fodder), cultural (land stewardship), regulating (landslide and avalanche risk), and supporting services (plant diversity). By analyzing the relative effects of the physical environment and land use on relevant ecosystem attributes, we also show that these ecosystem services are most sensitive to changes in grassland management, supporting current agri-environmental policies aimed at maintaining mowing of subalpine grasslands in Europe. 相似文献
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