Fertilizer application control in reason is the key technology to improve operation quality, reduce fertilizer pollution, and cut down costs of production. A control system of variable rate fertilizer is developed based on microcontroller chip in the paper. The system can automatically control flow dosage by adjusting feed gate opening size and changing hydraulic motor speed of fertilizer conve...

Understanding the microbial community structure of agricultural soils is important for better soil management in order to improve soil quality. Phospholipid fatty acid analysis has been popularly used in determining the microbial community structure in different ecosystems. The microbial community structure of paddy soil under long-term fertilizer treatments was investigated after 45 years usin...

Phosphorus (P) is a critical nutrient used to maximize plant growth and yield. Current agriculture management practices commonly experience low plant P use efficiency due to natural chemical sorption and transformations when P fertilizer is applied to soils. A perplexing challenge facing agriculture production is finding sustainable solutions to deliver P more efficiently to plants. Using presc...

Whereas point sources of nutrients are well understood and controllable, there is growing concern about non-point sources, especially those that are related to individual property owners. Modeling tools were used to analyze and visualize the fate of nitrogen from three anthropogenic sources: septic tanks, atmospheric deposition, and fertilizer. Our results suggest that septic tanks may be a les...

In dairy production systems, tradeoffs can occur between fertilizer N applications and crop N use, feed N consumption and manure N excretion, and environmental impacts. This paper examines (i) how stocking rates affect N imports and management on dairy farms, N use efficiency (NUE; i.e., the amount of applied N incorporated into product N), and N loss; (ii) how reductions in fertilizer N and fe...

This note demonstrates that a certain class of stochastic problems for determination of optimal fertilizer application rates in the presence of fertilizer carry-over can be simplified to static, certainly equivalent problems. Conditions required for certainty equivalence to hold are: (1) fertilizer carry-over is agronomically equivalent to applied fertilizer; and (2) some addition of fertilizer...

Nutrient management for production, profit, and environmental protection: Striking the balance Strategies to manage nutrients in crop production were first designed to maximize crop yields, an objective that became increasingly possible with the development of inorganic fertilizers during the past century. Later, as economic analysis of farm profitability became more sophisticated, strategies s...

application of bio-fertilizers, especially mycorrhiza as substituent or complement of chemical fertilizers is one of the most important strategies for plant nutrition in sustainable management of agro-ecosystems. in order to evaluate the separated and integrated application of mycorrhiza biological fertilizer and phosphorus chemical fertilizers on growth indices of chickpea (cicer arietinum l.)...

abstract soil nutrient management with efficient fertilizer use has an important role on maximizing yield and environmental effects. in this study game theory is applied to identify the nutrient proportion for corn production in kooshkak in fars province, iran, in 2008-2009. cost of fertilizer combinations and production of corn are the players of the game. a goal programming was applied to obt...