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 ...

The negative effects of pollution on amphibians are especially high when animals are additionally stressed by other environmental factors such as water salinity. However, the stress provoked by salinity may vary among populations because of adaptation processes. We tested the combined effect of a common fertilizer, ammonium nitrate (0-90.3 mg N-NO3NH4/L), and water salinity (0-2 per thousand) o...

Recent human population increase has been enabled by a massive expansion of global agricultural production. A key component of this "Green Revolution" has been application of inorganic fertilizers to produce and maintain high crop yields. However, the long-term sustainability of these practices is unclear given the eutrophying effects of fertilizer runoff as well as the reliance of fertilizer p...

AIMS The recent increases in food prices caused by the corresponding increases in fertilizer costs have highlighted the demand for reducing the overuse of fertilizers in industrial agriculture. There has been increasing interest in developing plant root-targeted delivery (RTD) of fertilizers in order to address the problem of inefficient fertilizer use. The aim of this study is to develop a low...

Nutrient management is central in water footprint analyses as it exerts strong control over crop yield and potentially contributes to pollution of freshwater, the so-called grey water footprint. In the frame of grey water footprint accounting, two methods are suggested, the constant leaching fraction approach (10% of applied fertilizer N) and the N surplus approach. We compared both approaches ...

Returning crop residue may result in nutrient reduction in soil in the first few years. A two-year field experiment was conducted to assess whether this negative effect is alleviated by improved crop residue management (CRM). Nine treatments (3 CRM and 3 N fertilizer rates) were used. The CRM treatments were (1) R0: 100 % of the N using mineral fertilizer with no crop residues return; (2) R: cr...

A study was conducted at Mahailluppallama, in the Low country Dry zone (DL1b) of Sri Lanka, during Maha (2008/2009) to determine the fertilizer requirement of Okra when planted at closer spacings. Three (03) fertilizer levels (T1DOA recommendation/ plant, 2 DOA recommendation/ unit area and T31 1⁄2 times DOA recommendation/ unit area) were tested using Okra varieties Haritha and Green Tender (F...

Use of dairy manure to supply crop nutrients is gaining broader acceptance as the cost of fertilizer rises. However, there are concerns regarding manure's effect on water quality. In 2003 and 2004, we measured sediment, NO3-N, NH4-N, K, dissolved reactive P (DRP), and total P (TP) concentrations in runoff from furrow irrigated field plots (6-7 irrigations yr(-1)) cropped to corn (Zea mays L.) i...

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...

Currently the world is moving towards organic production of crops for the discovered and envisaged advantages. Despite this, farmers are faced with the challenges of the bulkiness of organic fertilizer to be used and further gains that could be accrued from it even if sacrifice of using it is made. To be quite sure of the appropriate fertilizer type to be used in improving quality as well as th...