نتایج جستجو برای: because soil moisture condition affects vegetation changes hence

تعداد نتایج: 2151105  

Journal: :مرتع و آبخیزداری 0
فاطمه هادیان کارشناس ارشد مرتع داری، دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان رضا جعفری استادیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان حسین بشری استادیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان سعید سلطانی دانشیار دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان

because soil moisture condition affects vegetation changes hence, monitoring of drought and vegetation changes are among valuable management tools in these ecosystems. nowadays, satellite images are used as a low-cost and fast method for vegetation study in different scales. vegetation change is assessed using vegetation spectral characteristics. this study aimed to analyze and monitor the vege...

2014
X. H. MENG J. P. EVANS M. F. MCCABE

Moderate Resolution Imaging Spectroradiometer (MODIS)-derived vegetation fraction data were used to update the boundary conditions of the advanced research Weather Research and Forecasting (WRF) Model to assess the influence of realistic vegetation cover on climate simulations in southeastAustralia for the period 2000–08. Results show that modeled air temperature was improved when MODIS data we...

Journal: :Remote Sensing 2015
Yitong Jiang Peng Fu Qihao Weng

Urbanization-associated land use and land cover (LULC) changes lead to modifications of surface microclimatic and hydrological conditions, including the formation of urban heat islands and changes in surface runoff pattern. The goal of the paper is to investigate the changes of biophysical variables due to urbanization induced LULC changes in Indianapolis, USA, from 2001 to 2006. The biophysica...

Rangeland ecosystems in arid and semiarid regions strongly were influenced by climatic factors and their kind of exploitation of management. These changes usually occur in combination and structure of vegetation over time. Because understanding the dynamics of pasture can choose the appropriate management practices and proper help, The changes of vegetation in desert ecosystem of Jajarm area, b...

2017
Sibo Zhang Nicolas Roussel Karen Boniface Minh Cuong Ha Frédéric Frappart José Darrozes Frédéric Baup Jean-Christophe Calvet

This work aims to estimate soil moisture and vegetation characteristics from Global Navigation Satellite System (GNSS) Signal to Noise Ratio (SNR) data using direct and reflected signals by the land surface surrounding a ground-based antenna. Observations are collected over a rainfed wheat field in southwestern France. The retrievals are compared with two independent reference datasets: in situ...

2015
Clara Chew Eric E. Small Kristine M. Larson

Ground-reflected global positioning system signals measured by a geodetic-quality GPS system can be used to infer temporal changes in near-surface soil moisture for the area surrounding the antenna. This technique, known as GPS-interferometric reflectometry, analyzes changes in the interference pattern of the direct and reflected signals, which are recorded in signal-to-noise ratio (SNR) data, ...

2002
William L. Crosson Charles A. Laymon Ramarao Inguva Marius P. Schamschula

A key state variable in land surface–atmosphere interactions is soil moisture, which affects surface energy fluxes, runoff and the radiation balance. Soil moisture modelling relies on parameter estimates that are inadequately measured at the necessarily fine model scales. Hence, model soil moisture estimates are imperfect and often drift away from reality through simulation time. Because of its...

2012
Brian Barrett Pádraig Whelan Ned Dwyer

Soil moisture estimation studies using Synthetic Aperture Radar (SAR) routinely utilise only the amplitude part of the received echo. In this study, repeat-pass Cand L-band interferometric SAR coherence from 2007 2009 was evaluated for the detection of surface soil moisture changes in the presence of vegetation using two different approaches. In the first analysis, the association between low c...

2001
FEI CHEN JIMY DUDHIA

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 co...

Journal: :Remote Sensing 2010
Dugwon Seo Tarendra Lakhankar Reza Khanbilvardi

Sensitivity analysis is critically needed to better understand the microwave emission model for soil moisture retrieval using passive microwave remote sensing data. The vegetation b-factor along with vegetation water content and surface characteristics has significant impact in model prediction. This study evaluates the sensitivity of the b-factor, which is function of vegetation type. The anal...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید