River export of nitrogen (N) is influenced strongly by spatial variation in anthropogenic N inputs and climatic variation. We developed a model of riverine N export for 18 Lake Michigan Basin watersheds based on N budgets at 5-year intervals from 1974 to 1992. N inputs explained a high proportion of the spatial variation in river export but virtually none of the temporal variation, whereas betw...

Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m(-2) preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m(-2). No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice ...

Rhizobia form symbiotic nitrogen-fixing nodules on leguminous plants, which provides an important source of fixed nitrogen input into the soil ecosystem. The improvement of symbiotic nitrogen fixation is one of the main challenges facing agriculture research. Doing so will reduce the usage of chemical nitrogen fertilizer, contributing to the development of sustainable agriculture practices to d...

Computer models have been widely used to evaluate the impact of agronomic management on nitrogen (N) dynamics in subsurface drained fields. However, they have not been evaluated as to their ability to capture the variability of nitrate-nitrogen (NO(3)-N) concentration in subsurface drainage at a wide range of N application rates due to possible errors in the simulation of other system component...

Our researches have been made on brown forest soil that had been used in long-term experiments set up according to specified fertilization system for over 30 years. We have chosen those experiment variants in which quantities of nitrogen fertilizers were gradually increased. The soil samples taken from 0 cm to 30 cm depth were used to determine biological indexes of nitrogen availability (aerob...

Due to the increase in food-borne diseases, especially recent years, consumers' orientation healthy products and their emphasis on consumption force producers environmentally friendly products. Nitrogen is most widely used plant nutrient world. Nitrogen, a very expensive input due its excessive use, pollutes environment causes nitrate accumulation plants. Therefore, vegetable growers strive rep...

The use of fertilizers is an important measure to increase and improve the quality fodder obtained from temporary meadows (Barbulescu C. colab. 1987). From research carried out by us, it resulted that mineral fertilizers, especially nitrogen-based, contribute not only biomass harvest, respectively its quality, but improvement structure species used make up mixture herbs. In this sense, for area...

BiofertiJizers are microbial preparations containing living cells of different microorganisms which have the ability to mobilize plant nutrients in soil from unusable to usable form through biological process. They are environmental friendly and play significant role in crop production. Previollsly it is mainly used for field crops but now-a-days it is used for fruit crops also. Biofertilizers ...

The main purpose of this study is to perform a nitrogen budget survey for the entire Brazilian Amazon region. The main inputs of nitrogen to the region are biological nitrogen fixation occurring in tropical forests (7.7 Tg.yr(-1)), and biological nitrogen fixation in agricultural lands mainly due to the cultivation of a large area with soybean, which is an important nitrogen-fixing crop (1.68 T...