Arsenic (As) is a toxic metalloid which is usually found in rice fields as a contamination and has negative effects on the plant growth and reduces the crop yield. Similar to heavy metals, the deleterious effects of As may be due to, at least in part, the amount of absorbed As and disturbance of the plant water status. I...

Orthomosics and digital surface models (DSM) derived from aerial imagery, acquired by consumer-grade cameras, have the potential for crop type mapping. In this study, a novel method was proposed for extracting the crop height from DSM and for evaluating the orthomosics and crop height for the identification of crop types (mainly corn, cotton, and sorghum). The crop height was extracted by subtr...

Returning crop residue improves water conservation and storage, nutrient availability, and crop yields. We have little knowledge, however, of the residual impacts of crop residues on soil and crop production. We hypothesized that residual impacts of crop residues vary with the amount of residues used. A 10-yr study near Lincoln, NE, evaluated the residual effects of an earlier 8-yr study of var...

The next advance in field crop productivity will likely need to come from improving crop use efficiency of resources (e.g., light, water, and nitrogen), aspects of which are closely linked with overall crop photosynthetic efficiency. Progress in genetic manipulation of photosynthesis is confounded by uncertainties of consequences at crop level because of difficulties connecting across scales. C...

introduction: elimination or reduction of tillage in conservation agricultural systems has led to wide variations in germination, emergence, and growth of weeds and has caused variations in the density and diversity of weeds under such systems. maintaining crop residues on the soil surface has many potential benefits in agricultural production systems; such as reducing water and wind erosions, ...

assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. this study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. 309 in gorazbon district in kheyrud educational and research forest. the objective of this stu...

BACKGROUND Proctological surgery is being carried out increasingly on an outpatient basis. The reasons for this are safe anesthetic procedures, short operation times and low complication rates. This study is a retrospective analysis of complication rates, symptom recurrence and long-term results according to outpatient proctologic surgery practiced in our hospital in the last 10 years. MATERI...

Crop water requirement is essential for agricultural water management, which is usually available for crop growing stages. However, crop water requirement values of monthly or weekly scales are more useful for water management. A method was proposed to downscale crop coefficient and water requirement from growing stage to substage scales, which is based on the interpolation of accumulated crop ...

Continuous Stirred Tank Reactor (CSTR) has particular importance in chemical industry. CSTR has usually a nonlinear behavior which makes it difficult to control. The reactor has two parameters: the concentration and temperature of mixture both of which are uncertain. This case of CSTR has large disturbance in domain. In order for disturbance rejection, a controller has to be designed. In this p...