نتایج جستجو برای: drainage network density

تعداد نتایج: 1101403  

Journal: :International Journal of Geographical Information Science 2013
Ling Zhang Eric Guilbert

In both GIS and terrain analysis, drainage systems are important components. Owing to local topography and subsurface geology, a drainage system achieves a particular drainage pattern based on the form and texture of its network of stream channels and tributaries. Although research has been done on the description of drainage patterns in geography and hydrology, automatic drainage pattern recog...

2007
Alaa El-Sadek Jan Feyen Jean Berlamont

Some of the highest losses of nitrate to surface waters come from drained agricultural land. Given previous this article studied for Belgian farming conditions (i) the effect of subsurface drainage density on nitrate losses and (ii) the economics of nitrate emissions, using the nitrogen version of DRAINMOD (Brevé et al., 1997 a and b). DRAINMOD (Skaggs, 1997) was used to simulate the performanc...

2000
Xihua Yang Qiming Zhou Mike Melville

This is the ®rst of two papers that elaborate an integrated drainage network analysis system (IDNAS) for agricultural drainage management. In this paper, the system components, functions and implementation are presented. The IDNAS comprises an agricultural drainage network module, an evapotranspiration (ET) module and an event-based spatio-temporal module. The network module is designed to mode...

1998
Gregory E. Tucker Rafael L. Bras

Catchment morphology and drainage density are strongly influenced by hillslope processes. The consequences of several different hillslope process laws are explored in a series of experiments with a numerical model of drainage basin evolution. Five different models are considered , including a simple diffusive-advective process transition, a runoff-generation threshold, an erosion threshold, and...

2003
M. L. Collier T. F. Stepinski S. M. Clifford P. J. McGovern

Martian terrains are represented as a series of drainage basins, regardless of the historical presence or absence of actual fluid flow. A statistical analysis of each drainage network, computationally extracted from an underlying topography based on the MOLA data, yields a network descriptor, a compact, numerical characterization of a network. These descriptors are used to compare different mar...

2007
Wei Luo Tomasz Stepinski Yi Qi

This paper demonstrates a feasibility of automated drainage density mapping on regional scales and in high resolution, using remotely sensed elevation data. Such maps offer affordable means of surveying large regions for variability in spatially extended features, which themselves are difficult to sense remotely, but are expressed by the drainage density. We show that the proposed mapping metho...

Arash Mahjobi, Kazem Torfi Mohammad Albaji

Koot - Hamoodi are two units from seventh units out of 1&2 irrigation and drainage network in Dasht-Azadeghan project where was past about 7 years from their operation. Results of the studies were showed before construction of network; ground water table in considered of this area was high and more than 90% of these lands were high and too high in saline and alkaline. After construction and ope...

In the study, Drainmod model was used to compare measured water table depth fluctuations on the farm with those simulated by the model, also comparison of measured drainage outflow of the farm drains and model simulated was investigated. This study was made in a part of the Irrigation and Drainage Network of ABADAN Date palms. By statistical analysis of the measured and predicted water table de...

Journal: :Geographical Review of Japan 1972

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید