Synthetic nitrogen (N) fertilizer has played a key role in enhancing food production and keeping half of the world's population adequately fed. However, decades of N fertilizer overuse in many parts of the world have contributed to soil, water, and air pollution; reducing excessive N losses and emissions is a central environmental challenge in the 21st century. China's participation is essentia...

Introduction ield experience and research demonstrate that manure nutrients can be readily substituted for commercial fertilizer. Fertilizer needs depend on soil test levels. Substituting manure at a lower cost than commercial fertilizer can result in signifi cant savings if relatively uniform application and distribution can be maintained. The less nutrient-dense manure requires more hauling o...

The current precision fertilization technology of maize is still incomplete and unsystematic. In the paper, according to the fact of maize production of black soil zone in Jilin province, spatial variability of soil nutrient is studied, precision fertilization model of maize is introduced, a web-based expert system for maize precision fertilization is developed. Finally, the precision fertiliza...

A simultaneous equations, or "switching-regression," model is developed to assess the impact of soil nitrogen (N) testing on N fertilizer use, crop yields, and net returns in corn growing areas of Nebraska. The results indicate that when there is uncertainty about the quantity of available "carry-over" N, N testing enables farmers to reduce fertilizer use without affecting crop yields. However,...

The biomass and quality of Pseudostellariae heterophylla suffers a significant decline under monoculture. Since rhizosphere miobiome plays crucial roles in soil health, deep pyrosequencing combined with qPCR was applied to characterize the composition and structure of soil bacterial community under monoculture and different amendments. The results showed compared with the 1st-year planted (FP),...

To investigate the interacting effects of polymer coated urea (PCU) and polymer coated potassium chloride (PCPC) on cotton growth, an experiment was conducted with containerized plants in 2014 and 2015. There were two kinds of nitrogen fertilizer, PCU and urea, which were combined with PCPC at three application rates (40, 80 and 120 kg ha-1). The kinds of nitrogen fertilizer formed the main plo...

Field experiments are described involving nitrogen fertilizer in wheat field to research its effect on microbial quantity and enzyme activity. The results showed that 250 kg N hm applied in wheat field (1) can increase bacteria, fungi, actinomycetes quantity by 39.9%, 56.7% and 70.5% compare to 0 kg N hm. (2) Similarly, the activities of soil urease, catalase and FDA expressed 60.8%, 18.3% and ...

Soil fertility evaluation and management can be greatly improved with the use of precision agriculture technologies. Differential global positioning systems (DGPS), yield monitors, various forms of remote sensing, geographical information system (GIS) computer software, and variable rate technologies are available for use to producers. Intensive soil sampling, crop scouting, and other practices...

Soil fertility evaluation and management can be greatly improved with the use of precision agriculture technologies. Differential global positioning systems @GPS), yield monitors, various forms of remote sensing, geographical information system (GIs) computer software, and variable rate technologies are available for use to producers. Intensive soil sampling, crop scouting, and other practices ...

Agronomic practices can modify olive fruit and oil quality. However, there is little information on the influence of fertigation, a common practice in most intensive orchards. We studied nutrient distribution in the soil profile following fertigation with different doses of N-P-K fertilizer, and its effect on nutrient concentrations, yield and both table olive and oil quality. Measurements were...