This paper presents an approach to estimating soil moisture content through fitting an inverted Gaussian function to the continuum in soil spectra. The soil moisture Gaussian model (SMGM) estimates the water content by the declining reflectance in the near infrared (NIR) and shortwave infrared (SWIR) regions, 1.2–2.5 Am, due to the spreading of the fundamental water absorption at 2.8 Am. Convex...

the accuracy and effectiveness of precision agriculture is highly depending on accuracy and time analysis of the soil moisture conditions. monitoring of the soil water status is a proper method for optimizing the agricultural irrigation. automation irrigation, based on soil moisture measurement by smart sensors has the potential to provide maximum water use efficiency by maintaining soil moistu...

Nitrogen is one of the important indexes to evaluate the physiological and biochemical properties of soil. The level of soil nitrogen content influences the nutrient levels of crops directly. The near infrared sensor can be used to detect the soil nitrogen content rapidly, nondestructively, and conveniently. In order to investigate the effect of the different soil water content on soil nitrogen...

Dalton, F.N. and van Genuchten, M.Th., 1986. The time-domain reflectometry method for measuring soil water content and salinity. Geoderma, 38: 237--250. This paper discusses the physical principles and use of time-domain reflectometry as a new tool for studying water and solute transport in unsaturated soils. In-situ measurements of water content and bulk soil electrical conductivity are shown ...

Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ...

Soil particle size distribution (PSD), one of the most important soil physical attributes, is of great importance to soil water movement, soil erosion and soil solute migration. In this study, the soil PSD of 563 soil samples from the mulched drip irrigated cotton fields in Xinjiang of China were measured by laser diffraction particle size analyzer. The soil PSD characteristics and its relation...

The Soil-Water Characteristic Curve (SWCC) is an important soil function relating the water content of a soil to soil suction. Many unsaturated soil properties (or soil property functions) can be related to the water content versus suction relationship of a soil. Hydraulic conductivity, shear strength, chemical diffusivity, water storage, unfrozen volumetric water content, specific heat, and th...

The Earth's atmosphere will continue to be enriched with carbon dioxide (CO2) over the coming century. Carbon dioxide enrichment often reduces leaf transpiration, which in water-limited ecosystems may increase soil water content, change species abundances and increase the productivity of plant communities. The effect of increased soil water on community productivity and community change may be ...

Data from Spanish and Italian olive orchards with different cultivars (‘‘Manzanilla’’, ‘‘Frantoio’’, ‘‘Leccino’’, ‘‘Razzola’’ and ‘‘Taggiasca’’) growing in different environments (southern Spain; north, centre and south of Italy) were used to illustrate how models on water use and photosynthetic behaviour of the olive tree can be useful tools for choosing pruning intensity and canopy shape for ...