Download or read book Spatiotemporal Drivers of Tributary Nutrient Dynamics written by Robert James Mooney and published by . This book was released on 2020 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Disentangling the Drivers of Spatiotemporal Dynamics in Trophic Metacommunities written by Diana L. Townsend and published by . This book was released on 2020 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Understanding the relative influence of endogenous and exogenous factors on population dynamics has been a key focus of ecology since its inception. Endogenous processes such as dispersal and local interactions have historically been associated with maintaining "the balance of nature" in the form of equilibrium population dynamics, while exogenous processes such as environmental fluctuations have been deemed responsible for perturbing populations away from their natural equilibrium states. However, May (1974) showed that nonlinear species interactions could induce more complex dynamics such as limit cycles and chaos. In doing so, May helped put an end to the simplistic suggestion that the complexity of population dynamics could be used to infer their drivers, with endogenous processes being stabilizing and exogenous processes being destabilizing. Spatial synchrony, which measures the degree to which the abundances of disjunct populations are correlated over time, has been shown to be a much more potent tool for identifying the drivers of population dynamics and stability across scales. Synchrony and stability are expected to be inversely related, as increased synchrony across populations promotes the risk for stochastic extinction and thus disrupts the balance of nature (Gouhier et al. 2010a; Abbott 2011). This dissertation focuses on demonstrating how multiple drivers of synchrony interact to affect population dynamics, stability, and persistence. Chapter one explores how spatial and interspecific differences in recruitment affect the relationship between dispersal, synchrony, and stability in a trophic metacommunity. Using a keystone food web model, I show that the relationship between dispersal, synchrony, and stability can be complex. Specifically, intermediate levels of dispersal dampen population fluctuations and synchrony, no matter the degree of correlation in recruitment across species. However, high levels of dispersal generate large oscillations in population size, especially when recruitment is correlated across species, but buffers population abundances via a trophic decoupling effect when there are interspecific differences in recruitment. Thus, spatial and interspecific heterogeneity in recruitment can interact to produce complex relationships between dispersal, synchrony, and stability in trophic metacommunities. Chapter two removes the assumption present in many models that dispersal is described by a time-invariant statistical distribution. In reality, dispersal is temporally stochastic, and only mimics these static assumptions when it is averaged over many generations (Siegel et al. 2008), thus creating an implicit separation of time scales between local and regional dynamics. Using a trophic metacommunity with temporally stochastic and spatially aggregated dispersal that varies at the same time scale as local dynamics, I show that removing this separation of time scales disrupts the effect of dispersal-induced synchrony. Increasing dispersal shifts control of population dynamics from local interactions to regional processes, no matter the degree of spatial aggregation in dispersal. This results in an increase in the magnitude and the frequency of population fluctuations, which prevents spatial synchrony. Spatial aggregation in recruitment promotes boom-and-bust cycles and thus extinctions, which can be prevented by decreasing spatial aggregation or allowing species to disperse independently, which promotes stability. Overall, these results suggest that relaxing the implicit separation of time scales assumption in classic models is critical for understanding the relationship between dispersal, synchrony, and stability in nature. Finally, chapter three expands this work by not only focusing on the synchronizing effect of dispersal, but also the effect of spatial and temporal autocorrelation in the environment. Using a predator-prey model, I analyze the complex interplay between these synchronizing factors, and their effect on the dynamics, persistence, and stability of communities across scales. Low levels of dispersal, both in the absence of the environment and with weak environmental fluctuations, can induce non-stationary population dynamics. Temporal autocorrelation in the environment also disrupts the synchronizing ability of spatially autocorrelated environmental fluctuations, as well as the synchronizing effect of high levels of dispersal, even though reddened environments are expected to promote synchrony due to increased memory. Strong environmental fluctuations promote extinctions, especially under temporally autocorrelated environments, but dispersal can limit these extinctions, as long as the environment is spatially uncorrelated. These results suggest that the influence of autocorrelation in the environment on synchrony, stability, and persistence depends on the degree of environmental variability and dispersal. Taken together, the results presented in this dissertation suggest that dispersal-induced synchrony may be less common in systems characterized by heterogeneous dispersal or environments. These results are critical in a time of human-induced global change, as disruptions in processes such as dispersal and environmental fluctuations are likely. Specifically, recent work has shown that the environment is becoming more spatially and temporally autocorrelated, which removes the possibility for species to escape extreme events to spatial or temporal refugia (Di Cecco and Gouhier 2018). Thus, understanding the complex effects of and interactions between endogenous and exogenous processes is key in order to predict community responses to global change events"--Author's abstract.

Download or read book Lake Taihu China written by Boqiang Qin and published by Springer Science & Business Media. This book was released on 2008-07-22 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: 2 In China, there are more than 2,759 lakes with surface area greater than 1km , and 2 the total lake area is 91,019km . One-third of these lakes are freshwater lakes, and the majority are situated in the middle and lower reaches of the Changjiang River or in eastern China’s coastal areas. These lakes function as drinking water supplies, ood control systems, aquaculture and tourism resources, navigation channels, etc. Recently, many shallow lakes in China have been subject to rapid eutrophication and suffer from algal blooms. This issue has resulted in a shortage of drinking water and in degradation of their ecosystems. The control of eutrophication of shallow lakes is one of the main issues with which the local people and Chinese governments are concerned today. Lake Taihu is the third largest freshwater lake in China, with an area of about 2 2338km and a mean depth of 1. 9m, a typical shallow lake located in the delta of Changjiang River, the most industrialized and urbanized area in China. Its main function is supplying drinking water for the surrounding cities, such as Wuxi, Suzhou, and Shanghai, but tourism, aquaculture, sheries, and navigation are imp- tant as well. However, with economic development and increased population in the lake basin, Lake Taihu has suffered increasingly from serious eutrophication. The environmental issue of Lake Taihu is now a very common one, as most lakes from eastern China are confronted with it.

Download or read book Selected Papers from the 14th Estuarine and Coastal Modeling Conference written by Richard P. Signell and published by MDPI. This book was released on 2018-06-27 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Selected Papers from the 14th Estuarine and Coastal Modeling Conference" that was published in JMSE

Download or read book Biogeochemistry of Wetlands written by K. Ramesh Reddy and published by CRC Press. This book was released on 2022-09-10 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: The globally important nature of wetland ecosystems has led to their increased protection and restoration as well as their use in engineered systems. Underpinning the beneficial functions of wetlands are a unique suite of physical, chemical, and biological processes that regulate elemental cycling in soils and the water column. This book provides an in-depth coverage of these wetland biogeochemical processes related to the cycling of macroelements including carbon, nitrogen, phosphorus, and sulfur, secondary and trace elements, and toxic organic compounds. In this synthesis, the authors combine more than 100 years of experience studying wetlands and biogeochemistry to look inside the black box of elemental transformations in wetland ecosystems. This new edition is updated throughout to include more topics and provide an integrated view of the coupled nature of biogeochemical cycles in wetland systems. The influence of the elemental cycles is discussed at a range of scales in the context of environmental change including climate, sea level rise, and water quality. Frequent examples of key methods and major case studies are also included to help the reader extend the basic theories for application in their own system. Some of the major topics discussed are: Flooded soil and sediment characteristics Aerobic-anaerobic interfaces Redox chemistry in flooded soil and sediment systems Anaerobic microbial metabolism Plant adaptations to reducing conditions Regulators of organic matter decomposition and accretion Major nutrient sources and sinks Greenhouse gas production and emission Elemental flux processes Remediation of contaminated soils and sediments Coupled C-N-P-S processes Consequences of environmental change in wetlands# The book provides the foundation for a basic understanding of key biogeochemical processes and its applications to solve real world problems. It is detailed, but also assists the reader with box inserts, artfully designed diagrams, and summary tables all supported by numerous current references. This book is an excellent resource for senior undergraduates and graduate students studying ecosystem biogeochemistry with a focus in wetlands and aquatic systems.

Download or read book Intermittent Rivers and Ephemeral Streams written by Thibault Datry and published by Academic Press. This book was released on 2017-07-11 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intermittent Rivers and Ephemeral Streams: Ecology and Management takes an internationally broad approach, seeking to compare and contrast findings across multiple continents, climates, flow regimes, and land uses to provide a complete and integrated perspective on the ecology of these ecosystems. Coupled with this, users will find a discussion of management approaches applicable in different regions that are illustrated with relevant case studies. In a readable and technically accurate style, the book utilizes logically framed chapters authored by experts in the field, allowing managers and policymakers to readily grasp ecological concepts and their application to specific situations. Provides up-to-date reviews of research findings and management strategies using international examples Explores themes and parallels across diverse sub-disciplines in ecology and water resource management utilizing a multidisciplinary and integrative approach Reveals the relevance of this scientific understanding to managers and policymakers

Download or read book The Mekong written by Ian Charles Campbell and published by Academic Press. This book was released on 2009-11-20 with total page 647 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mekong is the most controversial river in Southeast Asia, and increasingly the focus of international attention. It flows through 6 counties, China, Myanmar, Laos, Thailand, Cambodia and Viet Nam. The 4 downstream countries have formed the Mekong River Commission to promote sustainable development of the river and many of their people depend on it for their subsistence ? it has possible the largest freshwater fishery in the world, and the Mekong waters support rice agriculture in the delta in Viet Nam (which produces about 40% of that country's food) as well as in Cambodia, Laos and Thailand. China is now building the first large mainstream dam on the river, and has proposals for several more. These dams are likely to affect the downstream countries. Several of the downstream countries also have plans for large scale hydropower and irrigation development which could also impact the river. This book will provide a solid overview of the biophysical environment of the Mekong together with a discussion of the possible impacts, biophysical, economic and social, of some possible development scenarios. It is intended to provide a technical basis which can inform the growing political and conservation debate about the future of the Mekong River, and those who depend on it. It is aimed at river ecologists, geographers, environmentalists and development specialists both in the basin and (especially) outside for whom access to this material is most difficult. This book will be the first comprehensive treatment of the Mekong system. The first comprehensive overview of all aspects of the Mekong River system Deals with a regionally critical ecosystem and one under threat The Mekong supports the world's largest freshwater fishery and provides water underpinning a major regional rice paddy system Presents the authoritative findings of the Mekong River Commission's research for a wider audience for the first time outside of limited distribution reports

Download or read book Ecosystem Function in Heterogeneous Landscapes written by Gary M. Lovett and published by Springer Science & Business Media. This book was released on 2005-12-15 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: This groundbreaking work connects the knowledge of system function developed in ecosystem ecology with landscape ecology's knowledge of spatial structure. The book elucidates the challenges faced by ecosystem scientists working in spatially heterogeneous systems, relevant conceptual approaches used in other disciplines and in different ecosystem types, and the importance of spatial heterogeneity in conservation resource management.

Download or read book River Confluences Tributaries and the Fluvial Network written by Stephen Rice and published by John Wiley & Sons. This book was released on 2008-07-31 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: River Confluences and the Fluvial Network brings together state of the art thinking on confluence dynamics tributary impacts and the links between processes at these scales and river network functions. The book is unique in focus, content, scope and in bringing together engineering, ecological and geomorphological approaches to the three key areas of river system science. Taking a global approach this multi-authored text features a team of carefully selected, internationally renowned, experts who have all contributed significantly to recent ground breaking advancements in the field. Each chapter includes a comprehensive review of work to date highlighting recent discoveries and the main thrust of knowledge, previously unpublished research and case studies, challenges and questions, detailed references as well as a forward looking assessment of the state of the science.

Download or read book Estuarine Indicators written by Stephen A. Bortone and published by CRC Press. This book was released on 2004-12-28 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acknowledging the present inability to determine objectively the status and trends among estuarine ecosystems, the environmental research community has recently stepped up efforts to develop and evaluate meaningful estuarine indicators. This goal requires the effort of researchers from a broad spectrum of disciplines. In order to expedite this init

Download or read book Riverine Ecology Volume 1 written by Susanta Kumar Chakraborty and published by Springer Nature. This book was released on 2021-03-01 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is part of a two-volume set that offers an innovative approach towards developing methods and tools for assigning conservation categories of threatened taxa and their conservation strategies by way of different phases of eco-restoration in the context of freshwater river systems of tropical bio-geographic zones. The set provides a considerable volume of research on the biodiversity component of river ecosystems, seasonal dynamics of physical chemical parameters, geo-hydrological properties, types, sources and modes of action of different types of pollution, river restoration strategies and methodologies for the ongoing ecological changes of river ecosystems. Volume 1 provides an in-depth analysis of different theories with international relevance pertaining to the functioning of river ecosystems, shaping their structure and contributing ecological services, and includes the principles of riverine ecology such as biogeochemical cycles, physiography, hydrogeology, and physico-chemical parameters. It covers the basic concepts and principles of water within riverine ecosystems, and the underlying ecological principles operating to ensure ecological stability and sustainability of the fluvial ecosystem. The book explains the ecofunctionality of different geo-morphological, geo-hydrological and physico-chemical factors and processes in changing time scales and spaces, with special emphasis on the tropical fresh water rivers in India.

Download or read book The Freshwater Algal Flora of the British Isles written by David M. John and published by . This book was released on 2021-08-05 with total page 897 pages. Available in PDF, EPUB and Kindle. Book excerpt: First comprehensive guide of its kind, this volume is essential for any study of freshwater algae in the British Isles.

Download or read book Phosphorus Biogeochemistry of Sub Tropical Ecosystems written by K. Ramesh Reddy and published by CRC Press. This book was released on 1999-04-29 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phosphorus is one of the major nutrients limiting the productivity of terrestrial, wetland and aquatic ecosystems. Over the last decade several research projects were conducted on Florida's ecosystems from state and federal agencies and private industry to address water quality issues, and to develop management practices to control nutrient loads. Phosphorus Biogeochemistry in Sub-Tropical Ecosystems is the first thorough study of the role of phosphorus in ecological health and water quality ever published. Because of its vast and extensively studied ecosystems, Florida has often served as a national laboratory on current and future trends in ecosystem management. The reader will find studies at all levels of biological organization, from the cellular to entire ecological communities. The book is a definitive study of the role and behavior of phosphorus deposition in the upland/wetland/aquatic environment. The papers presented in this book are organized in specific groups: ecological analysis and global issues, biogeochemical transformations, biogeochemical responses, transport processes, phosphorus management, and synthesis. Although Florida's ecosystems are used as a case study, the results presented have global applications.

Download or read book Landscape Ecology in Theory and Practice written by Monica G. Turner and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: An ideal text for students taking a course in landscape ecology. The book has been written by very well-known practitioners and pioneers in the new field of ecological analysis. Landscape ecology has emerged during the past two decades as a new and exciting level of ecological study. Environmental problems such as global climate change, land use change, habitat fragmentation and loss of biodiversity have required ecologists to expand their traditional spatial and temporal scales and the widespread availability of remote imagery, geographic information systems, and desk top computing has permitted the development of spatially explicit analyses. In this new text book this new field of landscape ecology is given the first fully integrated treatment suitable for the student. Throughout, the theoretical developments, modeling approaches and results, and empirical data are merged together, so as not to introduce barriers to the synthesis of the various approaches that constitute an effective ecological synthesis. The book also emphasizes selected topic areas in which landscape ecology has made the most contributions to our understanding of ecological processes, as well as identifying areas where its contributions have been limited. Each chapter features questions for discussion as well as recommended reading.

Download or read book Ecohydrological Interfaces written by Stefan Krause and published by John Wiley & Sons. This book was released on 2023-10-12 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecohydrological Interfaces Comprehensive overview of the process dynamics and interactions governing ecohydrological interfaces Summarizing the interdisciplinary investigation of ecohydrological interface functioning, Ecohydrological Interfaces advances the understanding of their dynamics across traditional subject boundaries. It offers a detailed explanation of the underlying mechanisms and process interactions governing ecohydrological interface functioning from the micro scale to the ecosystem and regional scale. The multidisciplinary team of authors integrates and synthesises the current understanding of process dynamics at different ecohydrological interfaces to develop a unifying concept of their ecosystem functions. The work introduces novel experimental and model-based methods for characterizing and quantifying ecohydrological interface processes, taking account of innovative sensing and tracing technologies as well as microbial and molecular biology approaches. Key questions addressed in the book include: Which conditions stimulate the transformative nature of ecohydrological interfaces? How are ecohydrological interfaces organized in space and time? How does interface activity propagate from small to large scales? How do ecohydrological interfaces react to environmental change and what is their role in processes of significant societal value? As a research level text on the functionality and performance of ecohydrological interfaces, Ecohydrological Interfaces is primarily aimed at academics and postgraduate researchers. It is also appropriate for university libraries as further reading on a range of geographical, environmental, biological, and engineering topics.

Download or read book Sources Fate and Transport of Nitrogen and Phosphorus in the Chesapeake Bay Watershed written by Scott W. Ator and published by Geological Survey (USGS). This book was released on 2011 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spatially Referenced Regression on Watershed Attributes (SPARROW) was used to provide empirical estimates of the sources, fate, and transport of total nitrogen (TN) and total phosphorus (TP) in the Chesapeake Bay watershed, and the mean annual TN and TP flux to the bay and in each of 80,579 nontidal tributary stream reaches. Restoration efforts in recent decades have been insufficient to meet established standards for water quality and ecological conditions in Chesapeake Bay. The bay watershed includes 166,000 square kilometers of mixed land uses, multiple nutrient sources, and variable hydrogeologic, soil, and weather conditions, and bay restoration is complicated by the multitude of nutrient sources and complex interacting factors affecting the occurrence, fate, and transport of nitrogen and phosphorus from source areas to streams and the estuary. Effective and efficient nutrient management at the regional scale in support of Chesapeake Bay restoration requires a comprehensive understanding of the sources, fate, and transport of nitrogen and phosphorus in the watershed, which is only available through regional models. The current models, Chesapeake Bay nutrient SPARROW models, version 4 (CBTN_v4 and CBTP_v4), were constructed at a finer spatial resolution than previous SPARROW models for the Chesapeake Bay watershed (versions 1, 2, and 3), and include an updated timeframe and modified sources and other explantory terms.

Download or read book River Conservation Challenges and Opportunities written by Sergi Sabater and published by Fundacion BBVA. This book was released on 2013 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: