نتایج جستجو برای: soil drainage

تعداد نتایج: 219137  

2007
Peter Almond Josh Roering T. C. Hales

[1] On hillslopes the balance between soil transport and production determines local soil thickness and the age distribution of particles that comprise the soil (where age refers to the time elapsed since detachment from bedrock). The mean of this age distribution is defined as the residence time, and in a landscape with time-invariant topography (i.e., morphologic steady state), the spatial un...

2005
M. S. SEYFRIED S. SCHWINNING M. A. WALVOORD W. T. POCKMAN B. D. NEWMAN R. B. JACKSON F. M. PHILLIPS

The amount and spatial distribution of deep drainage (downward movement of water across the bottom of the root zone) and groundwater recharge affect the quantity and quality of increasingly limited groundwater in arid and semiarid regions. We synthesize research from the fields of ecology and hydrology to address the issue of deep drainage in arid and semiarid regions. We start with a recently ...

2014
S. J. Matlan M. Mukhlisin M. R. Taha

Characterization of the engineering behavior of unsaturated soil is dependent on the soil-water characteristic curve (SWCC), a graphical representation of the relationship between water content or degree of saturation and soil suction. A reasonable description of the SWCC is thus important for the accurate prediction of unsaturated soil parameters. The measurement procedures for determining the...

2003
Yaping Shao Ann Henderson-Sellers

In the Soil Moisture Simulation Workshop, a number of numerical experiments was conducted with fourteen representative schemes and the results compared with HAPEX-MOBILHY data. This paper documents the general outcomes of the workshop, and provides the background information for the other papers presented in this special issue, which deal with more specific aspects of soil moisture simulation a...

Journal: :Remote Sensing 2016
Dana R. N. Brown Mark T. Jorgenson Knut Kielland David L. Verbyla Anupma Prakash Joshua C. Koch

Climate change coupled with an intensifying wildfire regime is becoming an important driver of permafrost loss and ecosystem change in the northern boreal forest. There is a growing need to understand the effects of fire on the spatial distribution of permafrost and its associated ecological consequences. We focus on the effects of fire a decade after disturbance in a rocky upland landscape in ...

2014
Letícia Bianca Pereira Renato Vicentini Laura M. M. Ottoboni

Mine drainage is an important environmental disturbance that affects the chemical and biological components in natural resources. However, little is known about the effects of neutral mine drainage on the soil bacteria community. Here, a high-throughput 16S rDNA pyrosequencing approach was used to evaluate differences in composition, structure, and diversity of bacteria communities in samples f...

2003
D. M. Amatya

Models like DRAINMOD and its forestry version, DRAINLOB, have been specifically developed as a field scale model for evaluating hydrologic effects of crops (trees), soil, and water management practices for lands with pattern drainage (i.e. with parallel ditches) on relatively flat, high water table soils. These models conduct a water balance between the ditches to predict water table depths, dr...

2017
J. D. Williams

Conservation tillage systems that reduce soil erosion and maintain or increase soil carbon offer long-term benefits for producers in the inland Pacific Northwestern United States but could result in reduced grain yields due to increased pressure from weeds, disease, and insect pests. Our objective was to compare runoff, soil erosion, and crop yields from a conventional tillage, wheat-fallow two...

Journal: :J. Imaging 2016
Matthew Aitkenhead Malcolm Coull Richard Gwatkin David Donnelly

Here we present work on using different types of soil profile imagery (topsoil profiles captured with a smartphone camera and full-profile images captured with a conventional digital camera) to estimate the structure, texture and drainage of the soil. The method is adapted from earlier work on developing smartphone apps for estimating topsoil organic matter content in Scotland and uses an exist...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید