Download or read book Simulated Effects of Elevated CO2 on Nitrogen Cycling Using the NuCM Model written by and published by . This book was released on 1998 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interactions between elevated CO2 and N cycling were explored using simulations generated by the Nutrient Cycling Model (NuCM) for a Pinus taeda site at Duke, North Carolina and a mixed deciduous site at Walker Branch, Tennessee. The simulations tested whether N limitation would prevent growth increase in response to elevated CO2 and whether growth response to CO2 in N-limited systems could be facilitated by increased biomass/N (reduced concentration) and/or increased litter N mineralization. Nitrogen limitation precluded additional growth when target growth rates and litterfall were increased (simulating potential response to elevated CO2) at the Duke site. At the Walker Branch site, increasing target growth and litterfall caused a slight (790) increases in growth. Reducing foliar N concentrations caused reduced growth because of N limitation created by reduced litter quality (C/N ratio), reduced decomposition and N accumulation in forest floor. These effects were most pronounced at the Duke site, where the forest floor N turnover rate was lower than at the Walker Branch site. Reducing wood N concentration allowed prolonged increases in growth because of greater biomass/N; however, N uptake was reduced, allowing greater N immobilization in the forest floor and soil. Increased N mineralization caused increased growth at the Duke site but not at Walker Branch.
Download or read book Carbon Dioxide and Environmental Stress written by Luo Yiqi and published by Elsevier. This book was released on 1999-04-13 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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?
Download or read book Elevated CO2 and N written by H. Harmens and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book N poor ecosystems may respond more to elevated CO2 than N rich ones in the longterm written by M G R (Melvin) Cannell and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hurley Pasture Model was used to examine the short and long-term responses of grazed grasslands in the British uplands to a step increase from 350 to 700 mu mol mol(-1) CO2 concentration ([CO2]) with inputs of 5 or 100 kg N ha(-1) y(-1). In N-rich grassland, [CO2] doubling quickly increased net primary productivity (NPP), total carbon (C-sys) and plant biomass by about 30%. By contrast, the N-poor grassland underwent a prolonged 'transient', when there was little response, but eventually NPP, C-sys and plant biomass more than doubled. The 'transient' was due to N immobilization and severe depletion of the soil mineral N pool. The large long-term response was due to slow N accumulation, as a result of decreased leaching, decreased gaseous N losses and increased N-2-fixation, which amplified the CO2 response much more in the N-poor than in the N-rich grassland. It was concluded that (i) ecosystems use extra carbon fixed at high [CO2] to acquire and retain nutrients, supporting the contention of Gifford et al. (1996), (ii) in the long term, and perhaps on the real timescale of increasing [CO2], the response (in NPP, C-sys and plant biomass) of nutrient-poor ecosystems may be proportionately greater than that of nutrient-rich ones, (iii) short-term experiments on nutrient-poor ecosystems may observe only the transient responses, (iv) the speed of ecosystem responses may be limited by the rate of nutrient accumulation rather than by internal rate constants, and (v) ecosystem models must represent processes affecting nutrient acquisition and retention to be able to simulate likely real-world CO2 responses.
Download or read book Carbon Dioxide and Terrestrial Ecosystems written by George W. Koch and published by Elsevier. This book was released on 1995-12-21 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of carbon dioxide extends from cellular to global levels of organization and potential ecological deterioration may be the result of increased CO2 in our atmosphere. Recently, the research emphasis shifted from studies of photosynthesis pathways and plant growth to ground-breaking studies of carbon dioxide balances in ecosystems, regions, and even the entire globe. Carbon Dioxide and Terrestrial Ecosystems addresses these new areas of research. Economically important woody ecosystems are emphasized because they have substantial influence on global carbon dioxide balances. Herbaceous ecosystems (e.g., grasslands, prairies, wetlands) and crop ecosystems are also covered. The interactions among organisms, communities, and ecosystems are modeled, and the book closes with an important synthesis of this growing nexus of research. Carbon Dioxide and Terrestrial Ecosystems is a compilation of detailed scientific studies that reveal how ecosystems generally, and particular plants specifically, respond to changed levels of carbon dioxide. - Contributions from an international team of experts - Empirical examination of the actual effects of carbon dioxide - Variety of terrestrial habitats investigated - Specific plants and whole ecosystems offered as studies
Download or read book Global Biogeochemical Cycles in the Climate System written by Ernst-Detlef Schulze and published by Elsevier. This book was released on 2001-08-10 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interactions of biogeochemical cycles influence and maintain our climate system. Land use and fossil fuel emissions are currently impacting the biogeochemical cycles of carbon, nitrogen and sulfur on land, in the atmosphere, and in the oceans.This edited volume brings together 27 scholarly contributions on the state of our knowledge of earth system interactions among the oceans, land, and atmosphere. A unique feature of this treatment is the focus on the paleoclimatic and paleobiotic context for investigating these complex interrelationships.* Eight-page colour insert to highlight the latest research* A unique feature of this treatment is the focus on the paleoclimatic context for investigating these complex interrelationships.
Download or read book Handbook of Climate Change and Agroecosystems written by Daniel Hillel and published by World Scientific. This book was released on 2011 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: The portending process of climate change, induced by the anthropogenic accumulations of greenhouse gases in the atmosphere, is likely to generate effects that will cascade through the biosphere, impacting all life on earth and bearing upon human endeavors. Of special concern is the potential effect on agriculture and global food security. Anticipating these effects demands that scientists widen their field of vision and cooperate across disciplines to encompass increasingly complex interactions. Trans-disciplinary cooperation should aim to generate effective responses to the portending changes, including actions to mitigate the emissions of greenhouse gases and to adapt to those climate changes that cannot be avoided. This handbook presents an exposition of current research on the impacts, adaptation, and mitigation of climate change in relation to agroecosystems. It is offered as the first volume in what is intended to be an ongoing series dedicated to elucidating the interactions of climate change with a broad range of sectors and systems, and to developing and spurring effective responses to this global challenge. As the collective scientific and practical knowledge of the processes and responses involved continues to grow, future volumes in the series will address important aspects of the topic periodically over the coming years.
Download or read book Belowground Responses to Rising Atmospheric CO2 Implications for Plants Soil Biota and Ecosystem Processes written by P. S. Curtis and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Managed Ecosystems and CO2 written by Josef Nösberger and published by Springer Science & Business Media. This book was released on 2006-08-18 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an up-to-date review of the effects of increasing atmospheric carbon dioxide on agroecosystems, forests, and grasslands. It summarizes the main findings from 13 experiments with annual crops, permanent pastures and plantation forests at 11 sites throughout the world during the past ten years. The results significantly alter our perception of how rising CO2 will directly affect these managed ecosystems.
Download or read book The Effect of Elevated CO2 on Soil C and N Dynamics and Its Feedback on CO2 and N2O Emissions from a Temperate Grassland Ecosystem written by Lisa Keidel and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Elevated Carbon Dioxide and Chronic Warming on Nitrogen N Uptake and Assimilatory Proteins of Tomato Roots Provided Different Forms of Inorganic N nitrate and Ammonium written by Dileepa M. Jayawardena and published by . This book was released on 2015 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric CO2 enrichment is expected to benefit plant growth, despite causing global warming and nitrogen (N) dilution in plants. Most plants procure most of their N as two inorganic forms, nitrate (NO3- ) or ammonium (NH4+), using membrane-localized transport proteins in roots which are key targets of improving N-use efficiency in plants. Though it is expected that there will be interactive effects of elevated CO2, chronic warming, and N form on root N relations, this has not been studied. In this study, tomato (Solanum lycopersicum L. cv. Big Boy) plants were grown at two levels of CO2 (ambient=400 ppm vs. elevated=700 ppm) and under two temperature regimes (30oC vs. 37oC), while providing either NO3- (1.5 mM) or NH4+ (1.5 mM) as the sole N source. To assess plant N relations under these conditions, plant biomass (shoot, root, total), %N (shoot, root, total), root N-uptake rate, the concentration of total root proteins, and the concentration of N uptake and assimilatory proteins in roots per unit total root protein and per gram of dry root mass were measured. Elevated CO2 and chronic warming acted synergistically to severely inhibit the growth of plants, regardless of N form, while individually, these factors slightly increased growth. Although %N in roots among all treatments was similar, the combination of elevated CO2 and warming decreased (1) the rate of N uptake by roots, (2) the concentration of total protein in roots, indicating an inhibition of N assimilation (especially in NH4+-treated plants), and (3) shoot %N, indicating a possible negative effect on N translocation from roots to shoots (especially in NO3--treated plants). However, for the most part, the concentrations in roots of the main N-uptake and N-assimilation proteins were little affected by elevated CO2 and warming, and when affected, were not correlated with root total protein or N-uptake rate; hence, N uptake and assimilation in roots were controlled by the activities of these proteins rather than their concentrations. Taken together, these results indicate that elevated CO2 and chronic warming will act synergistically to decrease plant N uptake and assimilation, thereby decreasing growth and protein concentration; thus, future global warming may potentially decrease both crop production and its food quality.
Download or read book Effect of Elevated Carbon Dioxide on Nitrogen Nutrition in Wheat written by S. Lekshmy and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Availability of nitrogen (N) is a critical factor determining plant responses to high CO2. Elevated CO2 affects N metabolism, depending on the nitrogen source. However limited information is available on how various forms of N affects morphology and metabolism of plant under elevated CO2. Similarly elevated CO2 induces changes in stomatal and epidermal parameters in plants. Different N forms had profound effects on morphology both under ambient CO2 and elevated CO2. The negative effects of ammonium nutrition were manifested as reduction in root length, root surface area, chlorophyll a: b ratio, and thinner leaves, in elevated CO2 also. When ammonium nutrition was supplemented with nitrate ions, enhancement of various morphological, biochemical and anatomical parameters was more in ECO2 than when only nitrate was given. Hence supplimenting nitrate nutrition with ammonium ions might be beneficial for wheat under elevated CO2 conditions in future
Download or read book Climate Change and Global Crop Productivity written by K. R. Reddy and published by CABI. This book was released on 2000-04-25 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation. Worldwide climatic changes have been raising concerns about potential changes to crop yields and production systems. Such concerns include the ability to accommodate these uncertain effects in order to ensure an adequate food supply for an increasing population. Written by leadinginternational experts, this book is the first comprehensive examination of the potential effects climate change, particularly green house gases, will have on agroecosystems. It also reviews the effects such systems have on climate change itself.
Download or read book Environmental Variability and Experimental Method as Factors Influencing Plant Response to Elevated Atmospheric Carbon Dioxide written by Tammy Mishell Long and published by . This book was released on 1997 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plant Responses to Elevated CO2 written by A. Raschi and published by Cambridge University Press. This book was released on 1997-11-28 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rise in the concentration of CO2 in the atmosphere since the start of industrialization, and the global warming associated with this greenhouse gas, has stimulated research into the response of plants to elevated levels of CO2. Much of this work has been carried out in controlled environments which provide limited information about long-term effects on vegetation. In contrast, CO2-emitting mineral springs provide a unique opportunity to consider vegetation which has endured over many generations at naturally elevated levels of CO2. This volume presents findings from a range of sites, confirming the potential of these natural laboratories in the investigation of this important aspect of climate change.
Download or read book Photosynthesis and Production in a Changing Environment written by D.O. Hall and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of the world's people depend research work should be carried out at the local and regional level by locally trained on plants for their livelihood since they grow them for food, fuel, timber, fodder and people. many other uses. A good understanding Following the success of our earlier book of the practical factors which govern the (Techniques in Bioproductivity and Photo synthesis; Pergamon Press, 1985), which productivity of plants through the process of photosynthesis is therefore of paramount was translated into four major languages, importance, especially in the light of cur the editors and contributors have exten rent concern about global climate change sively revised the content and widened the and the response of both crops and natural scope of the text,· so it now bears a title ecosystems. in line with current concern over global The origins of this book lie in a series of climate change. · In particular, we have training courses sponsored by the United added chapters on remote sensing, con Nations Environment Programme (Project trolled-environment studies, chlorophyll No. FP/6108-88-0l (2855); 'Environment fluorescence, metabolite partitioning and changes and the productivity of tropical the use of mass isotopes, all of which grasslands'), with additional support from techniques are increasing in their applica many international and national agencies. tion and importance to this subject area.
Download or read book The impact of rising carbon dioxide levels on crop nutrients and human health written by Smith, Matthew R. and published by Intl Food Policy Res Inst. This book was released on 2018-07-06 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon dioxide (CO2) levels are rising globally at a rapid pace, on track to surpass 550 parts per million (ppm) by midcentury. Studies have found that, when grown under elevated CO2 concentrations of 546–586 ppm, many food crops—including wheat, rice, barley, and soybeans—have lowered concentrations of nutrients, including many that are important for overall health, such as iron, zinc, and protein. Elevated CO2 also affects both the quantity and quality of forage, thereby affecting animal performance and production and, consequently, the availability of nutrients from animal-source foods, such as meat, milk, and eggs. This loss of dietary nutrients in foods could translate to increased nutritional deficiency for hundreds of millions of people already on the brink of deficiency—mainly developing countries in Asia, the Middle East, and North Africa based on dietary preferences for the commodities most affected. This policy note examines the link between rising CO2 levels and declining nutritional content for a number of major crops, as well as forage. The discussion includes a comparison of the varying effects by crop, and strategies to address this challenge in the context of climate change.
