Leaf area index (LAI) is a major indicator for crop growth monitoring and yield estimation. Data assimilation as an effective tool for crop LAI estimation fully considers the properties of actual observations and physical model simulations. In this work, we present a new data assimilation scheme, introducing a very fast simulated annealing (VFSA) optimization algorithm into the process of crop ...

The adaptive responses of crop genotypes and patterns of genotype x location (G x L) interaction are important to crop improvement as they are the basis for selection for specific adaptation and for elucidation of the causes of G x L interaction. Their legitimate assessment, however, requires yield data for the test genotypes for a large number of sites and over multiple years. Such data are se...

In field trials conducted at four sites in Hawaii, soybean (Glycine max) and bush bean (Phaseolus vulgaris) were either inoculated with homologous rhizobia, fertilized at high rates with urea, or left unamended. Crop phenology was assessed every few days. Rates of biomass and N accumulation and components of yield were measured five times during each crop cycle to assess the extent to which: (i...

the crop simulation models are heuristic tools in order to determine optimal of management strategies and analyzing yield stability in agroecosystems. the objective of this study was to evaluate cropsyst model ability for simulating of development, growth and yield of wheat cultivars from golestan province in response to planting date. the results of model evaluation were acceptable so that, th...

a r t i c l e i n f o Keywords: Crop model CSM DSSAT Genetic algorithm Hyperspectral LAI Model inversion Nitrogen Optimization PEST PROSAIL Simulation Wheat Yield Remote sensing technology can rapidly provide spatial information on crop growth status, which ideally could be used to invert radiative transfer models or ecophysiological models for estimating a variety of crop biophysical propertie...

Excessive N and water use in agriculture causes environmental degradation and can potentially jeopardize the sustainability of the system. A field study was conducted from 2000 to 2002 to study the effects of four N treatments (0, 100, 200, and 300 kg N ha(-1) per crop) on a wheat (Triticum aestivum L.) and maize (Zea mays L.) double cropping system under 70 +/- 15% field capacity in the North ...

Crop canopies and residues have been shown to intercept a significant amount of rainfall. However, rainfall or irrigation interception by crops and residues has often been overlooked in hydrologic modelling. Crop canopy interception is controlled by canopy density and rainfall intensity and duration. Crop residue interception is a function of crop residue type, residue density and cover, and ra...

precise application of the n fertilizer rate is critical to achieve maximum yield. in major regions, empirical methods were used for determining n fertilizer requirement. these methods cannot take into account variation in management and environmental conditions on determining fertilizer requirement. crop simulation models can provide an alternative means of determining the optimum crop n requi...