کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
82615 158405 2009 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Interception of water by pastures of Pennisetum clandestinum Hochst. ex Chiov. and Melinis minutiflora Beauv.
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علم هواشناسی
پیش نمایش صفحه اول مقاله
Interception of water by pastures of Pennisetum clandestinum Hochst. ex Chiov. and Melinis minutiflora Beauv.
چکیده انگلیسی

The conversion of montane cloud forests into pastures for grazing cattle is the main cause of important impacts on rivers and streams in most of the Andes. In order to evaluate the effects of vegetation changes we need to understand water fluxes, particularly canopy interception. We measured net precipitation responses by the canopies of Pennisetum clandestinum Hochst. ex Chiov. and Melinis minutiflora Beauv. under simulated rainfall. The samples were taken from grazed pastures during 1 year, digging out round mats of grass, placing them on wire-mesh devices after eliminating soil and underground biomass, and irrigating with different water amounts. The resulting data allow us to present a validated model for each species that predicts percentage of interception at different precipitation intensities taking into account previous canopy wetness within determined biomass ranges. We use these models to estimate 2 years of interception values for pastures of both species in the upper watershed of El Cañadón, Capaz River, Venezuelan Andes. Mean annual precipitation of El Cañadón is 1244 mm and the estimate of pasture interception was 36.5% and 31.8% for P. clandestinum and M. minutiflora, respectively. Interception models, such as the ones derived in this study, provide a basis for quantifying interception rates as a function of previous wetness of canopies and grass species.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Agricultural and Forest Meteorology - Volume 149, Issue 10, 1 October 2009, Pages 1616–1620
نویسندگان
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