نتایج جستجو برای: soil calibration
تعداد نتایج: 235038 فیلتر نتایج به سال:
Soil C 0 2 efflux is a major component of net ecosystem productivity (NEP) of forest systems. Combining data from multiple researchers for larger-scale modeling and assessment will only be valid if their methodologies provide directly comparable results. We conducted a series of laboratory and field tests to assess the presence and magnitude of soil COZ efflux measurement system x environment i...
The spatiotemporal distribution of soil moisture over the Tibetan Plateau is important for understanding the regional water cycle and climate change. In this paper, the surface soil moisture in the northeastern Tibetan Plateau is estimated from time-series VV-polarized Sentinel-1A observations by coupling the water cloud model (WCM) and the advanced integral equation model (AIEM). The vegetatio...
[1] The hydrologic response of upland watersheds is strongly controlled by soil (regolith) thickness. Despite the need to quantify soil thickness for input into hydrologic models, there is currently no widely used, geomorphically based method for doing so. In this paper we describe and illustrate a new method for predictive mapping of soil thicknesses using high-resolution topographic data, num...
The aim of the present work was to evaluate the possibilities of using sub-basin data for calibration of the Soil and Water Assessment Tool (SWAT) model in a small ungauged basin (46 ha) and its response. This small basin was located in the viticultural Anoia-Penedès region (north-east Spain), which suffers severe soil erosion. The data sources were: daily weather data from an observatory locat...
Compounds of Al, Fe, Ca, and Mg phosphates were particularly found in the Lake Okeechobee drainage basin in Florida. Identification of the spectral characteristics of these compounds would improve sensing of phosphorus (P) concentration in soil samples. This study investigated the effects of common soil P compounds on reflectance spectra of sandy soils using ultraviolet (UV), visible (VIS), and...
The measurement and control of soil moisture are the key technologies of precision agriculture. In order to real-time detect soil moisture content faster and more accurately, a portable soil moisture sensor based on NIR spectroscopy was developed. With the sixty soil samples collected from a winter jujube orchard, a linear regression model was established. The determination coefficients of the ...
Soil fertilizer management is important to adjust the soil fertility by supplying fertilizers at optimum level to achieve maximum yield at minimum environmental risks. Precision agriculture demands to develop better cost and time efficient methodologies for analysis of soil properties. Besides conventional techniques, sometimes spectroscopy is more accurate, fast, non-destructive and inexpensiv...
Neutron induced gamma spectra analysis (NGA) provides a means of measuring carbon in large soil volumes without destructive sampling. Calibration of the NGA system must account for system background and the interference of other nuclei on the carbon peak at 4.43 MeV. Accounting for these factors produced measurements in agreement with theoretical considerations. The continuous NGA mode was twic...
Images of representative clayey bare fields were chosen from a high spatial resolution hyperspectral dataset that was acquired with the prototypal airborne Hyper SIM-GA sensor from Selex Galileo simultaneously with ground soil spectral signatures and the collection of samples. After both the pre-processing and calibration of the SIM-GA data, the mapping procedure was developed using the 2-2.45 ...
The Palmer Drought Severity Index (PDSI), which uses hydrometeorological variables to solve a simple water balance equation in the soil and considers the drought or wet conditions as dynamic phenomena, is used for the assessment of drought conditions in many parts of the world. The main goal of this study was to assess the PDSI based on its original assumptions, its regionalized status, using t...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید