راهنمای فارسی مدل wepp 2011

برای دانلود به آدرس http://mgis.vastblog.com مراجعه بکنید.

DEFINITION AND TYPES OF WATERHARVESTING SYSTEMS

Water harvesting refers to the small-scale concentration, collection, storage, and use of rainwater runoff for both domestic and agricultural use. This definition implies that the catchment area from which the water is drawn is larger than the command area, where it is collected and used.

ادامه نوشته

Microcatchment Water Harvesting

Limited water availability is the primary factor controlling plant establishment and growth in the dry lands and deserts of the world. Water shortages are accentuated in disturbed areas where vegetation removal and alteration of the surface soil further limit surface water retention and infiltration into the soil.

ادامه نوشته

Technologies for water harvesting and soil moisture conservation in small watersheds for small-scale

Water is essential for all life and is used in many different ways - for food production, drinking and domestic uses and industrial use. It is also part of the larger ecosystem on which bio diversity depends. Precipitation, converted to soil and groundwater and thus accessible to vegetation and people, is the dominant pre-condition for biomass production and social development in dry lands.

ادامه نوشته

WATER EROSION

Causes of Water Erosion

Water erosion can occur when the rainfall or snowmelt exceeds the soil's ability to absorb the moisture and when there is sufficient slope to cause runoff. The rate and magnitude of soil erosion on cropland is controlled by the interplay of the following factors: (1) rainfall intensity and water runoff; (2) soil erodibility; (3) soil gradient and length; and (4) vegetation.

*From: Agriculture and Agri-Food Canada

ادامه نوشته