Nitrogen management continues to be diffi cult due to transformations of nitrogen fertilizers that are possible when applied to soil and the uncertainties of weather (Cabrera et al., 2008). Nitrogen (N) fertilizer in the form of urea is subject to ammonia volatilization through the activity of the urease enzyme found ubiquitously in soil (Kissel et al., 2008). Nitrate fertilizer is subject to l...

Phosphorus (P) fertilizer recommendations in most European countries are based on plant-available soil P contents and long-term field experiments. Site-specific conditions are often neglected, resulting in excessive P fertilizer applications. P fertilization experiments including relevant site and soil parameters were evaluated in order to analyze the yield response. The database comprises abou...

Nitrogen fertilizer applications, for maximum fertilizer efficiencies and crop yields, should be based on the N required by the crop during its various growth stages. The objectives of this paper were to identify the N requirements of the potato plant (Solarium tuberosurn L.) during growth and to evaluate selected soil and plant tissue tests as indicators of the plant's N status. Growth analysi...

Simple nitrogen (N) input/output balance calculations in agricultural systems are used to evaluate performance of nutrient management; however, they generally rely on extensive assumptions that do not consider leaching, denitrification, or annual depletion of soil N. We constructed a relatively complete N mass balance for the Big Ditch watershed, an extensively tile-drained agricultural watersh...

Information on the contribution of various soil nitrogen (N) sources to plant N uptake is often needed for the implementation of sustainable or site-specific management practices in agriculture. Considering the limitations of traditional methods in meeting these needs, this study investigated the potential of leaf δ15N as an early indicator of nutrient deficiency in cotton. The spatial and temp...

Biochar production and subsequent soil incorporation could provide carbon farming solutions to global climate change and escalating food demand. There is evidence that biochar amendment causes fundamental changes in soil nutrient cycles, often resulting in marked increases in crop production, particularly in acidic and in infertile soils with low soil organic matter contents, although comparabl...

The common use of soil-fertility control data in Croatia includes properties such as soil pH, organic matter content and plant-available phosphorus (P) and potassium (K) extracted by ammonium lactate (AL) solution. These data are commonly used for fertilizer recommendations for both field vegetable (Lončarić et al., 2003) and arable crops (Vukadinović et al., 1996). Also, the same soil data hav...

Effect of fertilizer applications and grazing exclusion on species composition and biomass in wet meadow restoration in eastern Washington. Fertilizer applications and grazing exclusion were used as restoration strategies in degraded wet meadows in eastern Washington to grow biomass in the root systems where it could not be grazed. We used a split-block design to test vegetation responses to si...

soil ph is one of the important chemical characteristics of soil that plays major role in growing of tea plant and affects on absorbing of food elements by plant and their usability. in this study, the effect of different calcium source was investigated on some of quantifying parameters in tea plant, ph and ec in tea soil. tea is plant with shallow roots, this shrubs grows two forms wild and fa...

Precision agriculture is the developing trend of modern agriculture, and the rational utilization of fertilizer is one of the key technologies in the precision agriculture, which needs to fertilize variably according to the crop needs and soil fertility conditions. Thus a fertilizer automated proportioning equipment is developed to Proportion the three fertilizers: Nitrogen fertilizer, Phosphor...