Effects of Elevated Atmospheric CO2 and Plant Species Diversity on Nutrient Relations in Grasslands PDF Download

Author: Pascal Alex Niklaus
Publisher:
ISBN:
Category :
Languages : en
Pages : 74

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Book Description
Biodiversität, Ökophysiologei, Nährstoffe.

Author: Raquel Henriques Flinker
Publisher:
ISBN:
Category :
Languages : en
Pages : 160

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Book Description
Increasing atmospheric carbon dioxide (CO2) leads to global warming. This can have several impacts on climate and on plant biodiversity, and has been the topic of many studies. The objective of this thesis was to understand the effects of higher atmospheric CO2 on soil moisture dynamics in the grasslands of central Minnesota using detailed hydrologic modeling to explain previous experimental observations at the BioCON site, a free-air CO2 enrichment experiment. The hydraulic properties and texture of soils collected from BioCON were determined in the laboratory through grainsize analysis and continuous evaporative drying to determine soil moisture retention curves and hydraulic conductivities. These results were used as input for numerical soil water flow and energy balance models. The models showed that vegetation presence and atmospheric CO2 concentrations significantly affected the soil moisture dynamics. Summer evapotranspiration (ET) had a higher variation for bare plots than for vegetated plots. This likely occurred because the vegetation provided a buffer against the variations in weather conditions. Vegetation not only retains part of the precipitation on its leaves, it also retains water in its structure and transpires while carrying out photosynthesis. Higher water content was also seen for the bare plots than for the vegetated soils. For some vegetated plots, there were differences between simulated and observed soil moisture. This could have been caused by a difference in plant composition and could suggest that different plant species can respond differently to varying CO2 atmospheric concentrations leading to different soil moisture dynamics. In addition to this, smaller ET values and higher soil water content values at vegetated elevated CO2 conditions than at ambient CO2 conditions were simulated. This was expected, as higher atmospheric CO2 is linked to higher plant water efficiency and larger biomass. For the simulations, higher values for stomatal resistance and higher plant and plant residue biomass were used. If increasing CO2 conditions in fact decreases ET, regional weather patterns could be affected as less ET could delay the speed that water flows through the water cycle.

Author: Stephen Reynolds
Publisher: Science Publishers
ISBN: 9781578083596
Category : Nature
Languages : en
Pages : 564

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Book Description
This book looks at significant current grassland problems and issues, and provides an insight into grassland productivity in diverse areas of the world, with their various production systems. There is a focus on recent technical advances and the prospects for further innovation, through twenty-one chapters by eminent grassland scientists, grouped into seven sections - forage germplasm; forage conservation; grass-based systems and organic production; climate change, biodiversity and biotechnology; geographical information systems; farmer and pastoralist participation; and regional developments. The book is timely in view of the expanding human and livestock populations, especially in arid and semi-arid environments, with the consequent pressure on the world's grasslands.

Author: David J. Gibson
Publisher: Cambridge University Press
ISBN: 1107195268
Category : Nature
Languages : en
Pages : 363

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Book Description
A comprehensive assessment of the effects of climate change on global grasslands and the mitigating role that ecologists can play.

Author: Iris Heike Köhler
Publisher:
ISBN:
Category :
Languages : en
Pages : 120

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Author: Luo Yiqi
Publisher: Elsevier
ISBN: 0080500714
Category : Science
Languages : en
Pages : 434

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This book focuses on the interactive effects of environmental stresses with plant and ecosystem functions, especially with respect to changes in the abundance of carbon dioxide. The interaction of stresses with elevated carbon dioxide are presented from the cellular through whole plant ecosystem level. The book carefully considers not only the responses of the above-ground portion of the plant, but also emphasizes the critical role of below-ground (rhizosphere) components (e.g., roots, microbes, soil) in determining the nature and magnitude of these interactions.* Will rising CO2 alter the importance of environmental stress in natural and agricultural ecosystems?* Will environmental stress on plants reduce their capacity to remove CO2 from the atmosphere?* Are some stresses more important than others as we concern ourselves with global change?* Can we develop predictive models useful for scientists and policy-makers?* Where should future research efforts be focused?

Author: Elsa Eleanor Cleland
Publisher:
ISBN:
Category :
Languages : en
Pages : 204

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Author: Tali Delius Lee
Publisher:
ISBN:
Category :
Languages : en
Pages : 276

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Book Description

Author: Richard D. Bardgett
Publisher: Oxford University Press
ISBN: 0199546878
Category : Nature
Languages : en
Pages : 312

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Book Description
Aboveground-Belowground Linkages provides the most up-to-date and comprehensive synthesis of recent advances in our understanding of the roles that interactions between aboveground and belowground communities play in regulating the structure and function of terrestrial ecosystems, and their responses to global change. It charts the historical development of this field of ecology and evaluates what can be learned from the recent proliferation of studies on the ecological and biogeochemical significance of aboveground-belowground linkages. The book is structured around four key topics: biotic interactions in the soil; plant community effects; the role of aboveground consumers; and the influence of species gains and losses. A concluding chapter draws together this information and identifies a number of cross-cutting themes, including consideration of aboveground-belowground feedbacks that occur at different spatial and temporal scales, the consequences of these feedbacks for ecosystem processes, and how aboveground-belowground interactions link to human-induced global change.

Author: Ernst-Detlef Schulze
Publisher: Springer Science & Business Media
ISBN: 3642580017
Category : Science
Languages : en
Pages : 527

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Book Description
The biota of the earth is being altered at an unprecedented rate. We are witnessing wholesale exchanges of organisms among geographic areas that were once totally biologically isolated. We are seeing massive changes in landscape use that are creating even more abundant succes sional patches, reductions in population sizes, and in the worst cases, losses of species. There are many reasons for concern about these trends. One is that we unfortunately do not know in detail the conse quences of these massive alterations in terms of how the biosphere as a whole operates or even, for that matter, the functioning of localized ecosystems. We do know that the biosphere interacts strongly with the atmospheric composition, contributing to potential climate change. We also know that changes in vegetative cover greatly influence the hydrology and biochemistry ofa site or region. Our knowledge is weak in important details, however. How are the many services that ecosystems provide to humanity altered by modifications of ecosystem composition? Stated in another way, what is the role of individual species in ecosystem function? We are observing the selective as well as wholesale alteration in the composition of ecosystems. Do these alterations matter in respect to how ecosystems operate and provide services? This book represents the initial probing of this central ques tion. It will be followed by other volumes in this series examining in depth the functional role of biodiversity in various ecosystems of the world.