Soil moisture is one of the most important variable that in uences the soil-vegetation-atmosphere uxes. However, due to its high temporal and spatial variability, it is dif cult to provide accurate quantitative information on soil moisture at regional and global scales. Different approaches exist, but remote sensing is the more appropriated to measure soil moisture values and its variations. It...

To date, few studies are conducted to quantify the effects of reduced ammonium (NH4+) and oxidized nitrate (NO3-) on soil CH4 uptake and N2O emission in the subtropical forests. In this study, NH4Cl and NaNO3 fertilizers were applied at three rates: 0, 40 and 120 kg N ha(-1) yr(-1). Soil CH4 and N2O fluxes were determined twice a week using the static chamber technique and gas chromatography. S...

abstract soil temperature is one of the key parameters affecting most hydrologic and agricultural processes. therefore, its measurement and prediction is very crucial. so far, the statistical regression methods have been used for estimation of soil temperature for specific location encountering with lack or shortage of data. in this work, soil temperature data are estimated at six different dep...

Understanding the spatial and temporal variations of soil moisture is crucial for the land surface processes and their management. Accurate estimation of spatial and temporal variations of soil moisture is important for various hydrological studies also. Recently, remote sensing techniques have been used to estimate soil moisture. Estimation of soil moisture by remote sensing techniques provide...

The boundary that separates the earth from the atmosphere is a crucial zone of study for meteorology and hydrology. Here, solar energy is partitioned into sensible heat which drives atmospheric circulation, latent heat needed for evaporation from the soil and transpiration of vegetation, and soil heat which warms the subsurface. Precipitation is partitioned into interception that evaporates dir...

Airborne remote sensing provides a viable option for high resolution mapping of nearsurface soil moisture that allows larger areas to be covered in greater spatial and temporal detail than has hereto been possible from traditional ground based techniques. However, the current retrieval algorithms require information on near-surface soil temperature and vegetation water content in order to estim...

Long-term measurements of soil nitrogen (N) transformations along an environmental gradient within the Coweeta Hydrologic Laboratory basin in western North Carolina showed a strong seasonal pattern and suggested that vegetation community typethrough its influence on soil properties-was an important regulating factor. Our objective was to determine the relative effects of biotic vs. abiotic fact...

Past research has demonstrated the potential of mapping soil moisture using both low frequency passive and active microwave measurements (e.g. Jackson et al., 1999; Wagner & Scipal, 2000). This resulted in formulating satellite missions carrying L-band microwave sensors capable of monitoring soil moisture globally. For example, a microwave radiometer has recently been launched by European Space...

Three things must happen at exactly the same time if an infectious plant disease is to occur. One, a susceptible plant must be in a vulnerable state. Two, the parasite that causes the disease must be in an infective stage. Three, environmental conditions must be favorable for disease development. The environment of a plant consists of the air around it and the soil in which it grows. The enviro...