Human alteration of Earth is substantial and growing. Between one-third and one-half of the land surface has been transformed by human action; the carbon dioxide concentration in the atmosphere has increased by nearly 30 percent since the beginning of the Industrial Revolution; more atmospheric nitrogen is fixed by humanity than by all natural terrestrial sources combined; more than half of all accessible surface fresh water is put to use by humanity; and about one-quarter of the bird species on Earth have been driven to extinction. By these and other standards, it is clear that we live on a human-dominated planet.

/pdf/human-domination-of-earth-s-ecosystems-5eevmqq987.pdf

Human Domination of Earth's Ecosystems

This paper addresses and documents a number of issues related to the implementation of an advanced land surface–hydrology model in the Penn State–NCAR fifth-generation Mesoscale Model (MM5). The concept adopted here is that the land surface model should be able to provide not only reasonable diurnal variations of surface heat fluxes as surface boundary conditions for coupled models, but also correct seasonal evolutions of soil moisture in the context of a long-term data assimilation system. In a similar way to that in which the modified Oregon State University land surface model (LSM) has been used in the NCEP global and regional forecast models, it is implemented in MM5 to facilitate the initialization of soil moisture. Also, 1-km resolution vegetation and soil texture maps are introduced in the coupled MM5–LSM system to help identify vegetation/water/soil characteristics at fine scales and capture the feedback of these land surface forcings. A monthly varying climatological 0.15° × 0.15° green ...

https://www.sjsu.edu/people/frank.freedman/courses/metr130/s1/Paper-Chen-and-Dudhia---MWR.pdf

Coupling an Advanced Land Surface–Hydrology Model with the Penn State–NCAR MM5 Modeling System. Part I: Model Implementation and Sensitivity

Soil carbon sequestration to mitigate climate change

We explore the role of lakes in carbon cycling and global climate, examine the mechanisms influencing carbon pools and transformations in lakes, and discuss how the metabolism of carbon in the inland waters is likely to change in response to climate. Furthermore, we project changes as global climate change in the abundance and spatial distribution of lakes in the biosphere, and we revise the estimate for the global extent of carbon transformation in inland waters. This synthesis demonstrates that the global annual emissions of carbon dioxide from inland waters to the atmosphere are similar in magnitude to the carbon dioxide uptake by the oceans and that the global burial of organic carbon in inland water sediments exceeds organic carbon sequestration on the ocean floor. The role of inland waters in global carbon cycling and climate forcing may be changed by human activities, including construction of impoundments, which accumulate large amounts of carbon in sediments and emit large amounts of methane to the atmosphere. Methane emissions are also expected from lakes on melting permafrost. The synthesis presented here indicates that (1) inland waters constitute a significant component of the global carbon cycle, (2) their contribution to this cycle has significantly changed as a result of human activities, and (3) they will continue to change in response to future climate change causing decreased as well as increased abundance of lakes as well as increases in the number of aquatic impoundments.

/pdf/lakes-and-reservoirs-as-regulators-of-carbon-cycling-and-1nvh2w013k.pdf

Lakes and reservoirs as regulators of carbon cycling and climate

A method is presented for developing probability density functions for parameters of soil moisture relationships of capillary head [h(θ)] and hydraulic conductivity [K(θ)]. These soil moisture parameters are required for the assessment of water flow and solute transport in unsaturated media. The method employs a statistical multiple regression equation proposed in the literature for estimating [h(θ)] or [K(θ)] relationships using the soil saturated water content and the percentages of sand and clay. In the absence of known statistical distributions for either [h(θ)] or [K(θ)] relationships, the method facilitates modeling by providing variability estimates that can be used to examine the uncertainty associated with water flow or solute transport in unsaturated media.

Developing joint probability distributions of soil water retention characteristics

Fundamentals of Soil Physics.

Preface. Acknowledgments. The Task of Soil Physics. General Physical Characteristics of Soils. Properties of Water in Relation to Porous Media. Texture, Particle Size Distribution, and Specific Surface. Nature and Behaviour of Clay. Soil Structure and Aggregation. Soil Water: Content and Potential. Flow of Water in Saturated Soil. Flow of Water in Unsaturated Soil. Movement of Solutes and Soil Salinity. Soil Air and Aeration. Soil Temperature and Heat Flow. Stree-Strain Relations an Soil Strength. Soil Compaction and Consolidation. Bibliography. Index.

Fundamentals of soil physics

Basic Relationships. The task of Soil Physics. General Physical Characteristics of Soils. The Solid Phase. Texture, Particle Size Distribution, and Specific Surface. Soil Structure and Aggregation. The Liquid Phase. Soil Water: Content and Potential. Flow of Water in Saturated Soil. Flow of Water in Unsaturated Soil. The Gaseous Phase. Soil Air and Aeration. Composite Properties and Behavior. Soil Temperature and Hear Flow. Soil Compaction and Consolidation. Tillage and Soil Structure Management. The Field--Water Cycle and Its Management. Infiltration and Surface Runoff. Internal Drainage and Redistribution Following Infiltration. Groundwater Drainage. Evaporation from Bare-Surface Soils. Uptake of Soil Moisture by Plants. Water Balance and Energy Balance in the Field. Bibliography. Index.

Introduction to soil physics

Key Topics include Soil Genesis Soil Chemistry and Mineralogy Soil Physics Hydrology Soil Biology Soil Ecology

Encyclopedia of Soils in The Environment

Keywords: Mecanique des sols ; Drainage ; Ecoulement souterrain Reference Record created on 2004-09-07, modified on 2016-08-08

Daniel Hillel

Papers

Fundamentals of Soil Physics.

Fundamentals of soil physics

Introduction to soil physics

Encyclopedia of Soils in The Environment

Applications of soil physics.