Evapotranspiration Over Heterogeneous Vegetated Surfaces


Book Description

The focus of this work is the development of models to estimate evapotranspiration (ET), investigating the partitioning between soil evaporation and plant transpiration at field and regional scales, and calculating ET over heterogeneous vegetated surfaces. Different algorithms with varying complexities as well as spatial and temporal resolutions are developed to estimate evapotranspiration from different data inputs. The author proposes a novel approach to estimate ET from remote sensing by exploiting the linkage between water and carbon cycles. At the field scale, a hybrid dual source model (H-D model) is proposed. It is verified with field observations over four different ecosystems and coupled with a soil water and heat transfer model, to simulate water and heat transfer in the soil-plant-atmosphere continuum. At the regional scale, a hybrid dual source scheme and trapezoid framework based ET model (HTEM), using remote sensing images is developed. This model is verified with data from the USA and China and the impact of agricultural water-saving on ET of different land use types is analyzed, in these chapters. The author discusses the potential of using a remote sensing ET model in the real management of water resources in a large irrigation district. This work would be of particular interest to any hydrologist or micro-meteorologist who works on ET estimation and it will also appeal to the ecologist who works on the coupled water and carbon cycles. Land evapotranspiration is an important research topic in hydrology, meteorology, ecology and agricultural sciences. Dr. Yuting Yang works at the CSIRO Land and Water, Canberra, Australia.




Remote Sensing of Evapotranspiration (ET)


Book Description

Evapotranspiration (ET) is a critical component of the water and energy balances, and the number of remote sensing-based ET products and estimation methods has increased in recent years. Various aspects of remote sensing of ET are reported in the 11 papers published in this book. The major research areas covered by this book include inter-comparison and performance evaluation of widely used one- and two-source energy balance models, a new dual-source model (Soil Plant Atmosphere and Remote Sensing Evapotranspiration, SPARSE), and a process-based model (ETMonitor); assessment of multi-source (e.g., remote sensing, reanalysis, and land surface model) ET products; development or improvement of data fusion frameworks to predict continuous daily ET at a high spatial resolution (field-scale or 30 m) by fusing the advanced spaceborne thermal emission reflectance radiometer (ASTER), the moderate resolution imaging spectroradiometer (MODIS), and Landsat data; and investigating uncertainties in ET estimates using an ET ensemble composed of several land surface models and diagnostic datasets. The effects of the differences between ET products on water resources and ecosystem management were also investigated. More accurate ET estimates and improved understanding of remotely sensed ET products are crucial for maximizing crop productivity while minimizing water losses and management costs.




Evapotranspiration in the Soil-Plant-Atmosphere System


Book Description

Evapotranspiration and its components (evaporation and transpiration) as a process is one of the basic terms of Earth's water balance; its importance is accented by the fact that transpiration is the vital element of the biomass production process. The second important property of evapotranspiration is its extreme consumption of solar energy, thus controlling the temperature of the atmosphere and creating favourable conditions for life. Evapotranspiration as an energy consuming process is also the connection between the energy and mass cycles of the Earth. Evapotranspiration is a process performing in the Soil–Plant –Atmosphere System (SPAS); therefore this book is presenting and quantifying it as a catenary process, describing transport of water in the soil, including root extraction patterns and methods of its evaluation. Transport of water through the plant and from the canopy to the atmosphere is also described and quantified. A variety of evapotranspiration (and its components evaporation and transpiration) calculation methods are described, starting from empirical methods up to the most sophisticated ones based on the solution of the transport equations of water and energy in the SPAS. The most important (and widely used) calculation method - modified Penman–Monteith method is described in details, ready to be used with data in the book only. Water balance method of evapotranspiration estimation as well as sap flow method description can be found in the book as well. The book can be used by hydrologists, biologists, meteorologists and other specialists as well as by ecology students. Key themes: soil hydrology – evapotranspiration – hydropedology– plant physiology – water movement in soils – evaporation – transpiration Dr. Viliam Novák is a water resources scientist at the Institute of Hydrology of the Slovak Academy of Sciences in Bratislava (Slovakia).




Instrumentation and Measurement Technologies for Water Cycle Management


Book Description

This book aims at presenting a unified framework for the description of working principles, recent advances and applications of cutting-edge measurement technologies for the water sector. Instrumentation and measurement technologies are currently playing a key role in the monitoring, assessment and protection of environmental resources. Measurement techniques and sensing methods for the observation of water systems are rapidly evolving and are requiring an increased multi-disciplinary participation. The whole water sector is characterised by multiple technological contexts concerning the monitoring of the resource, given the broad coverage that includes water from its natural domains to the men-made infrastructures. In particular, instrumentation and measurement technologies have a pervasive presence in all the necessary aspects for the assessment, monitoring and control of the water resource and of its relationship with the various environmental stressors, including the anthropic pressures. Therefore, the book aims at presenting how the diagnostics/monitoring methodologies and the related technologies can give an answer to the issues raised by the complex scenario characterising the water cycle management (WCM). The book is structured in five topical sections, grouped by similarity of their technological and/or applicative contexts.




Remote Sensing of Energy Fluxes and Soil Moisture Content


Book Description

Integrating decades of research conducted by leading scientists in the field, Remote Sensing of Energy Fluxes and Soil Moisture Content provides an overview of state-of-the-art methods and modeling techniques employed for deriving spatio-temporal estimates of energy fluxes and soil surface moisture from remote sensing. It also underscores the range
















The Dictionary of Physical Geography


Book Description

This fully-revised comprehensive fourth edition covers the whole field of physical geography including climate and atmosphere, geomorphology, biogeography, hydrology, oceans, Quaternary, environmental change, soils, remote sensing and GIS. This new edition reflects developments in the discipline during the last decade, with the expert advisory group providing an international perspective on the discipline of physical geography. Over 2000 entries that are self-contained or cross-referenced include 200 that are new to this edition, over 400 that are rewritten and updated, and new supporting references and additional recommended reading in many others. Entries removed from the last edition are available in the online resource. This volume is the essential reference point for students of physical geography and related environmental disciplines, lecturers and interested individuals alike.