Author: Hannes GamperPublisher:
ISBN:
Category :
Languages : en
Pages : 114
Book Description
Effects of Elevated Atmospheric CO2 on Arbuscular Mycorrhizal Fungi in an Agricultural Model Grassland
Author: Hannes GamperBelowground Responses to Rising Atmospheric CO2: Implications for Plants, Soil Biota, and Ecosystem Processes
Author: P. S. CurtisPublisher: Springer Science & Business Media
ISBN: 9401708517
Category : Science
Languages : en
Pages : 379
Book Description
As atmospheric CO2 increases there will almost certainly be alterations in soil carbon fluxes. It is likely that such alterations will be accompanied by changes in the partitioning of carbon between organic structures and to soil processes. These changes have the potential for further altering the structure and function of terrestrial ecosystems. While there has been increasing recognition of the importance of soil-mediated responses to global climate change, the nature and magnitude of these responses are not well understood. In an effort to expand our assessment of the significance of belowground responses to rising atmospheric CO2, a workshop has been organized that resulted in the peer-reviewed contributions that are contained in this volume.
Effects of Elevated Atmospheric Carbon Dioxide on the Arbuscular-mycorrhizal Symbiosis at the Host Plant, Plant Community, and Ecosystem Level
Author: Effects of Elevated Atmospheric CO2 on Soil Organic Carbon Dynamics in a Mediterranean Forest Ecosystem
Author: Fayez Raiesi GahrooeePublisher:
ISBN: 9789054858799
Category : Forest soils
Languages : en
Pages : 166
Book Description
Elevated atmospheric CO2 has the potential to change the composition and dynamics of soil organic matter (SOM) and consequently C and N cycling in terrestrial ecosystems. Because of the long-lived nature of SOM, long-lasting experiments are required for studying the effect of elevated CO2 on soil organic matter dynamics. Therefore, the study of ecosystems that have been exposed to long-term enhanced CO2 concentrations is highly desirable for better understanding feedback mechanisms between litter production, litter quality, soil organic matter decomposability and the atmospheric CO2 level. This work deals with the effect of enhanced atmospheric CO2 on chemical composition and C and N mineralization in a leaf litter-soil organic matter continuum around a mineral CO2 spring in a Mediterranean woodland ecosystem. Leaf litter from Quercus cerris L., Quercus pubescens Willd. and Smilax aspera L., and soil samples from the forest floor (F and HA layers) and 0-10 cm mineral soil were taken at elevated and ambient CO2 concentrations, and analyzed for chemical composition (C, N, lignin, cellulose, polyphenols). C and N mineralization in plant litter and soil samples were determined using litterbag and laboratory incubation methods. Elevated CO2 affected neither chemical composition nor elemental ratios of leaf litter. The C mineralization rate during litter decomposition was not affected by elevated CO2, in accordance with the absence of a CO2 effect on litter quality. Leaf litter produced at high CO2 had a higher N mineralization during the initial stage of decomposition period. This difference, however, disappeared at the end of the incubation. Q. pubescens had a higher litter quality than Q. cerris, and subsequently in vitro faster C and N mineralization rates, but litter decomposition under field conditions did not differ significantly between the two species. Total C contents in the forest floor were higher at elevated CO2, but not so in the 0-10 cm mineral soil. For the three layers, total N contents and C/N ratios were not affected by elevated CO2. Total C and N pool sizes in the forest floor were doubled by elevated CO2, but such effects were not seen in the 0-10 cm mineral soil. The C mineralization rates of the three soil layers of the areas exposed to elevated CO2 did not differ from those of the areas under ambient conditions. Although N immobilization in the F and HA layers from the elevated CO2 plots was lower, that of the 0-10 cm A horizon was not affected by high CO2. The increase in the organic carbon pool of the forest floor in the absence of an effect of elevated CO2 on litter quality and decomposability can be explained by increased biomass production under elevated CO2. Under elevated CO2 soil N pools also increased, but the rate of N immobilization in forest floor was lower than that under ambient CO2. This study of long-term CO2 effects casts some doubt on the common view that elevated CO2 changes litter quality of plants, and thereby slows down decomposability of litter and N release. Because species composition has a strong influence on C and N cycles than elevated CO2, effects of increasing atmospheric CO2 on species composition may be more important to feedbacks between CO2 concentration and soil organic matter than the CO2 effect on litter quality of a given species.
Effects of Elevated Atmospheric CO2 and Plant Species Diversity on Nutrient Relations in Grasslands
Author: Pascal Alex NiklausPublisher:
ISBN:
Category :
Languages : en
Pages : 74
Book Description
Biodiversität, Ökophysiologei, Nährstoffe.
Effects of Above- and Belowground Resource Distribution on the Ecology of Vesicular-arbuscular Mycorrhizas
Author: Julie Lynn WhitbeckImpacts of elevated atmospheric CO2 and temperature on plant community structure of a temperate grassland are modulated by cutting frequency
Author: H. HarmensElevated Atmospheric CO2 in a Semi-natural Grassland
Author: Erik SindhøjPublisher:
ISBN: 9789157657978
Category : Carbon dioxide
Languages : en
Pages : 36
Book Description
Impact of Arbuscular Mycorrhizas on Substainable Agriculture and Natural Ecosystems.
Author: S. GianinazziPublisher: Springer Science & Business Media
ISBN: 9783764350000
Category : Nature
Languages : en
Pages : 244
Book Description
This book deals with arbuscular mycorrhizas, an essential component of soil/plant systems occurring in the majority of plant species in natural agro-ecosystems. It contains the most recent advances in; the field of the development of biomolecular methods adapted to arbuscular mycorrhizal fungi; the promotion of innovative ecological research which considers biodiversity; elucidating the role of arbuscular mycorrhizas in plant development and root morphology; and defining the cellular and molecular basis of plant-fungus exchanges
Grassland Soil Moisture Dynamics in Response to CO2 and Biodiversity Manipulations
Author: Raquel Henriques FlinkerPublisher:
ISBN:
Category :
Languages : en
Pages : 160
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.