Download or read book Interactions Between Vegetation and Water Cycle In the Context of Rising Atmospheric Carbon Dioxide Concentration written by Léo Lemordant and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Except in Northern latitudes, the annual daily maximum temperature increases at a faster pace than the mean temperature, which is reinforced by vegetation feedbacks in Europe but reduced in North America. This work highlights the key role of vegetation in influencing future terrestrial hydrologic responses. Accurate representation of the response to higher atmospheric carbon dioxide concentration levels, and of the coupling between the carbon and water cycles are therefore critical to forecasting seasonal climate, water cycle dynamics and to enhance the accuracy of extreme event prediction under future climates in various regions of the globe.

Download or read book Managing Water Resources in the West Under Conditions of Climate Uncertainty written by National Research Council and published by National Academies Press. This book was released on 1991-02-01 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: The question of whether the earth's climate is changing in some significant human-induced way remains a matter of much debate. But the fact that climate is variable over time is well known. These two elements of climatic uncertainty affect water resources planning and management in the American West. Managing Water Resources in the West Under Conditions of Climate Uncertainty examines the scientific basis for predictions of climate change, the implications of climate uncertainty for water resources management, and the management options available for responding to climate variability and potential climate change.

Download or read book Direct Effects of Increasing Carbon Dioxide on Vegetation written by Boyd R. Strain and published by . This book was released on 1986 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct Effects of Increasing Carbon Dioxide on Vegetation written by Boyd R. Strain and published by . This book was released on 1985 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Interactions of Vegetation and Climate written by Gregory R. Quetin and published by . This book was released on 2017 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: The natural composition of terrestrial ecosystems can be shaped by climate to take advantage of local environmental conditions. Ecosystem functioning, e.g. interaction between photosynthesis and temperature, can also acclimate to different climatological states. The combination of these two factors thus determines ecological-climate interactions. The ecosystem functioning also plays a key role in predicting the carbon cycle, hydrological cycle, terrestrial surface energy balance, and the feedbacks in the climate system. Predicting the response of the Earth's biosphere to global warming requires the ability to mechanistically represent the processes controlling ecosystem functioning through photosynthesis, respiration, and water use. The physical environment in a place shapes the vegetation there, but vegetation also has the potential to shape the environment, e.g. increased photosynthesis and transpiration moisten the atmosphere. These two-way ecoclimate interactions create the potential for feedbacks between vegetation at the physical environment that depend on the vegetation and the climate of a place, and can change throughout the year. In Chapter 1, we derive a global empirical map of the sensitivity of vegetation to climate using the response of satellite-observed greenness to interannual variations in temperature and precipitation. We infer mechanisms constraining ecosystem functioning by analyzing how the sensitivity of vegetation to climate varies across climate space. Our analysis yields empirical evidence for multiple physical and biological mediators of the sensitivity of vegetation to climate at large spatial scales. In hot and wet locations, vegetation is greener in warmer years despite temperatures likely exceeding thermally optimum conditions. However, sunlight generally increases during warmer years, suggesting that the increased stress from higher atmospheric water demand is offset by higher rates of photosynthesis. The sensitivity of vegetation transitions in sign (greener when warmer or drier to greener when cooler or wetter) along an emergent line in climate space with a slope of about 59 mm/yr/C, twice as steep as contours of aridity. The mismatch between these slopes is evidence at a global scale of the limitation of both water supply due to inefficiencies in plant access to rainfall, and plant physiological responses to atmospheric water demand. This empirical pattern can provide a functional constraint for process-based models, helping to improve predictions of the global-scale response of vegetation to a changing climate. In Chapter 2, we use observations of vegetation interaction with the physical environment to identify where ecosystem functioning is well simulated in an ensemble of Earth system models. We leverage this data-model comparison to hypothesize which physiological mechanisms - photosynthetic efficiency, respiration, water supply, atmospheric water demand, and sunlight availability - dominate the ecosystem response in places with different climates. The models are generally successful in reproducing the broad sign and shape of ecosystem function across climate space except for simulating generally lower leaf area during warmer years in places with hot wet climates. In addition, simulated ecosystem interaction with temperature is generally larger and changes more rapidly across a gradient of temperature than is observed. We hypothesize that the amplified interaction and change are both due to a lack of adaptation and acclimation in simulations. This discrepancy with observations suggests that simulated responses of vegetation to global warming, and feedbacks between vegetation and climate, are too strong in the models. Finally, models and observations share an abrupt threshold between dry regions and wet regions where strong positive vegetation response to precipitation falls to nearly zero in places receiving around 1000 mm/year. In Chapter 3, we investigate how ecoclimate interactions change across seasons in the Amazon basin. We use observations of solar induced fluorescence from the Orbiting Carbon Observatory 2 (OCO2) to statistically analyze the sensitivity of fluorescence to synoptic variations in temperature and precipitation. In addition to studying the sensitivity of vegetation to climate across seasons, we use OCO2 measurements of total column water vapor (TCWV) and CO2 concentration (XCO2) to investigate the influence of the Amazon basin vegetation on the CO2 concentration and water vapor of the atmosphere leaving the basin. Our analysis determines the seasonal importance of vegetation activity on the outflow of CO2 from the Amazon basin, while providing evidence that transpiration is primarily driven by variations in temperature during the dry season, rather than photosynthesis. We establish a statistical relationship between fluorescence (as a proxy for vegetation photosynthesis), temperature, and precipitation, as well as the difference between the outflow of atmospheric water vapor from the inflow water vapor, basin fluorescence, temperature, and precipitation.

Download or read book Elevated Carbon Dioxide written by M.B. Kirkham and published by CRC Press. This book was released on 2016-04-19 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Between 1958 and 2008, the CO2 concentration in the atmosphere increased from 316 to 385 ppm. Continued increases in CO2 concentration will significantly affect long-term climate change, including variations in agricultural yields. Focusing on this critical issue, Elevated Carbon Dioxide: Impacts on Soil and Plant Water Relations presents research

Download or read book Ecological Responses and Adaptations of Crops to Rising Atmospheric Carbon Dioxide written by Zoltan Tuba and published by CRC Press. This book was released on 2005-08-31 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact of rising levels of greenhouse gases—and the global consequences for crops! Carbon dioxide is a major greenhouse gas that causes global warming and directly impacts every aspect of plant life and indirectly impacts animal and human life. Atmospheric carbon dioxide levels have risen dramatically over the past century, and though this could mean opportunities for better growth and increased yield of certain crops, other factors like weather extremes and changes to plant physiology may mitigate the positive effects. Ecological Responses and Adaptations of Crops to Rising Atmospheric Carbon Dioxide comprehensively analyzes every aspect of crop responses to increasing carbon dioxide as well as their productional significance for the world. Changes in the growth rate and yield of crops are explored, with attention given to the consequences of coming weather changes on production and the expected economic impact. Ecological Responses and Adaptations of Crops to Rising Atmospheric Carbon Dioxide takes the data gleaned from careful research to provide an in-depth vision of the impact of carbon dioxide on global temperatures, plant physiology, and the ecological and economic future of our world. Respected authorities thoroughly discuss the research detailing the complete range of issues from plant growth under increased carbon dioxide levels to the impact of rising air temperatures to the evolving ecophysiological responses within various crops. Extensive references provide opportunities for further research while detailed tables and graphs clearly illustrate data. Ecological Responses and Adaptations of Crops to Rising Atmospheric Carbon Dioxide explores the effects of carbon dioxide enrichment on: plants, crops, and vegetation—is it beneficial? growth, yield, and photosynthetic responses in rice the photosynthetic capacity and productivity of rice under field conditions—and the role of nitrogen fertilization forage and grain nitrogen content potato crops crop responses including interaction with temperature the growth of maize different agricultural systems around the world—such as central and southeastern Europe, northern climates, Sudan, citrus-growing regions, and others the production ecophysiology of Hungarian green pepper and much more! The impending changes in our world make Ecological Responses and Adaptations of Crops to Rising Atmospheric Carbon Dioxide a valuable text for educators and postgraduate students in the field of plant ecology and crop production and an essential resource for researchers in the fields of plant ecology, ecophysiology, agricultural crop production, and environmental sciences.

Download or read book Korps Politie Nederlandse Antillen rapport van de commissie Gorsira van onderzoek written by and published by . This book was released on 1981 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Vegetation Climate Interaction written by Jonathan Adams and published by Springer Science & Business Media. This book was released on 2007-04-27 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: An accessible account of the ways in which the world's plant life affects the climate. It covers everything from tiny local microclimates created by plants to their effect on a global scale. If you’ve ever wondered how vegetation can create clouds, haze and rain, or how plants have an impact on the composition of greenhouse gases, then this book is required reading.

Download or read book The Carbon Cycle written by T. M. L. Wigley and published by Cambridge University Press. This book was released on 2005-08-22 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reducing carbon dioxide (CO2) emissions is imperative to stabilizing our future climate. Our ability to reduce these emissions combined with an understanding of how much fossil-fuel-derived CO2 the oceans and plants can absorb is central to mitigating climate change. In The Carbon Cycle, leading scientists examine how atmospheric carbon dioxide concentrations have changed in the past and how this may affect the concentrations in the future. They look at the carbon budget and the "missing sink" for carbon dioxide. They offer approaches to modeling the carbon cycle, providing mathematical tools for predicting future levels of carbon dioxide. This comprehensive text incorporates findings from the recent IPCC reports. New insights, and a convergence of ideas and views across several disciplines make this book an important contribution to the global change literature.

Download or read book Atmospheric Carbon Dioxide and the Global Carbon Cycle written by John R. Trabalka and published by . This book was released on 1986 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Importance of Carbon nitrogen Interactions and Ozone on Ecosystem Hydrology During the 21st Century written by Benjamin Seth Felzer and published by . This book was released on 2009 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of various aspects of global change (e.g., climate change, changes in the chemistry of the atmosphere, such as CO2 and O3, and land-use change) on the hydrologic cycle are becoming an important research area. For example, with respect to increases in atmospheric CO2, recent work supports the contention that there will be reduced evapotranspiration and therefore increased water availability in a CO2-rich world. Our new research on this topic suggests that various aspects of global change combine to affect hydrology in terrestrial ecosystems, and that it is particularly important to include carbon-nitrogen interactions in these studies. We have developed a new version of the Terrestrial Ecosystems Model (TEM) to examine the effects of carbon-nitrogen interactions on the water cycle. This new version includes explicit modeling of the stomatal exchange of CO2 and water, as well as a new approach to carbon and nitrogen allocation in plants. Using this new version of TEM, we have performed a range of site-level and regional experiments across the eastern United States. For example, using data from Harvard Forest, MA, a predominantly deciduous mixed forest, we ran two transient simulations from 1700 to 2100, with and without considering nitrogen limitations on plant productivity. In both of these simulations, we allowed CO2 to double by 2100, but maintained present-day climate. In these two experiments, we found that runoff increased through the 21st century in response to elevated atmospheric CO2. Without nitrogen limitation on plant productivity, the increase in runoff was 12%. However, with nitrogen limitation on plant productivity, the increase in runoff nearly doubled to 21%. This difference in runoff response was the result of a stronger transpiration reduction associated with a smaller increase in photosynthesis in the nitrogen limitation case. In this resentation we will discuss a set of site-level and regional experiments that explore the effects of carbon-nitrogen interactions on the water cycle in the context of different combinations of global changes including climate changes, changes in nitrogen deposition, and changes in tropospheric ozone. Since the carbon and water cycles are tightly coupled, future considerations of ecohydrology must take into account carbon-nitrogen interactions and other multiple stresses that strongly influence the carbon cycle.

Download or read book Investigations on the Impacts of Land cover Changes And or Increased CO2 Concentrations on Four Regional Water Cycles written by Zhao Li and published by . This book was released on 2007 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A suite of simulations that combine reference (355ppmv), doubled and tripled CO2 concentrations alternatively without and with land-cover changes in four similar-sized study regions, the Yukon, Ob, St. Lawrence and Colorado basin and adjacent land, are performed with the fully coupled Community Climate System Model to investigate the impact on global and regional water cycles and the interaction of these regional water cycles with the global water cycle. The relative changes in water-cycle quantities caused by increased CO2 enhance with latitude and CO2 concentrations. Regional and global water cycles interactions are more pronounced in a warmer climate, but regional precipitation and evapotranspiration is affected differently in high-latitudes (Yukon, Ob) than mid-latitudes (Colorado, St. Lawrence). Land-cover changes can have comparable impacts on regional water cycles than increased CO2 concentrations do. Land-cover changes substantially alter the high-latitude water cycles through enhanced snow-albedo feedback and mid-latitude water cycles through vegetation activity in the warm season. The land-cover changes in different regions interact with each other through heat and moisture advections and secondary effects. This interaction enhances with increasing CO2 concentrations. Interactions between land-cover changes and increasing CO2 concentrations enhance with increasing CO2 due to the high sensitivity of regional water cycles to temperature changes"--Leaf iv.

Download or read book Interactive Effects of Elevated Carbon Dioxide Concentration with Nutrient Availability and Leaf Development on Plant Carbon Metabolism written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Carbon and Water Relations in Pinus Taeda written by Catarina Fernandes Moura and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Plants respond to changes in their local environment and, at the same time, influence the environment at a global scale. The molecular and physiological mechanisms regulating this interaction are not completely understood and this limits our capacity to predict the response of vegetation to future environmental changes. This dissertation combined tools from genomics, physiology, and ecology to examine the response of plants to environmental change. Specifically, it focused on processes affecting carbon and water exchange in forest trees because (1) trees are long-lived species that might face repeated environmental challenges; (2) relatively little information exists about the genes and the molecular mechanisms regulating structural and physiological traits in adult, long-lived woody plants; and (3) forest trees exchange a significant amount of carbon and water with the atmosphere and are therefore major players in the global carbon and water cycles. Water flux through forests depends both on environmental conditions (e.g., soil moisture) and on the hydraulic architecture of individual trees. Resistance to xylem cavitation is an important hydraulic trait that is often associated with drought tolerance but potentially at the cost of reduced carbon uptake. The second chapter of this dissertation evaluated the variation in resistance to xylem cavitation, hydraulic conductivity, wood anatomy traits, and leaf gas exchange across 14 co-occurring temperate tree species including both angiosperms and gymnosperms. The relationship between vulnerability to cavitation (psi50) and hydraulic conductivity within specific organs (i.e. stems and roots) was not significant when considering the phylogenetic association between species. However, even after phylogenetic correction, photosynthetic carbon uptake (A) was positively correlated with both stem and root psi50 and stomatal conductance (gs) was strongly correlated with root psi50. These results suggest that there is a trade-off between vulnerability to cavitation and water transport capacity at the whole-plant level, and that this functional relationship reflects an adaptive response to the environment. Forests are an important component of the global carbon cycle that can be directly impacted by a rise in atmospheric CO2 concentration. The third chapter of this dissertation investigated the effects of long-term exposure to elevated CO2 on the gene expression of mature, field-grown loblolly pine trees. Using cDNA microarrays, I compared the expression of 1784 pine transcripts in trees growing under ambient and those under elevated CO2 at monthly intervals throughout a growing season. Overall, more genes were upregulated than downregulated by elevated CO2 although the total number of genes differentially expressed varied throughout the season. The pattern of increasing number of differentially expressed genes until the peak of the growing season (July and August) followed by a decrease in that number, matched the seasonal trend of tree growth and photosynthetic response to elevated CO2 in this species. The seasonal trend also reflected the interaction among multiple abiotic factors intrinsic to field conditions and emphasized the relevance of evaluating the role of genes in their natural environment. Genes consistently upregulated by elevated CO2 were functionally associated with environmental sensing, cellular signaling, and carbon metabolism, in particular the degradation of carbohydrates through respiration. An increase in carbohydrates degradation is particularly relevant in the context of carbon balance of forest trees because of the potential for enhanced leaf and tree respiration leading to a reduced sink capacity for CO2. Loblolly pine produces several flushes of needles throughout the year each with an average lifespan of 19 months. Each year, two age classes of needles contribute to the annual carbon sequestration of the loblolly pine forest. To address the impact of leaf age on the effects of elevated CO2 in carbon metabolism regulation, I compared the gene expression profiles from trees under ambient and elevated CO2 conditions in two needle cohorts: one-year-old and current-year. Differential expression under elevated CO2 was seven times more frequent in current-year than in one-year-old needles. Despite differences in magnitude, many of the patterns within specific groups of genes were similar across age classes. For instance, there was a trend for downregulation of genes involved in the light-reactions of photosynthesis and those in photorespiration in both age classes, while genes associated with dark respiration were largely upregulated by elevated CO2 in both cases. The difference between the two cohorts was particularly evident in the group of genes related to energy production (ATP synthesis) and the group associated with carbon partitioning (sucrose and starch metabolism). Because sucrose and starch metabolism categories included many genes known to be important regulators of gene expression and plant physiological processes, this suggests that this stage of carbon metabolism might be an important control point in age-dependent foliar responses to elevated CO2. This dissertation examined both structural and physiological components of plant water and carbon relations (Chapter 2) across different biological scales of organization (whole-plant level in Chapter 2; gene-level response to ecosystem-level changes in Chapters 3 and 4) and reflecting adjustments at distinct temporal scales (life-span of the organism vs. evolutionary selection of traits). An integrative approach was used to advance our understanding of how plants acclimate and adapt to their environment, and to provide a mechanistic framework for predictive models of plant response to environmental change.

Download or read book Climate Change Impacts on Plant Biomass Growth written by Mohammad Ali and published by Springer Science & Business Media. This book was released on 2012-09-03 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a methodical explanation of our biomass-driven ecosystem, the undeniable uncertainties posed by the response of vegetation to changes in environmental conditions and the fact that humans everywhere have an interest, even an obligation, to cooperate in a global campaign to combat climate change.