Urban agriculture has a high potential to contribute local circular economies, for instance by using nitrogen, phosphorus, and potassium in city organic waste streams as fertilizer inputs. However, inefficient use of waste-derived fertilizers could water quality impairment related nitrogen phosphorus losses. Organic derived are particularly challenging from nutrient stoichiometry perspective, m...

Mining of nutrients from soil is a major problem causing soil degradation and threatening long-term food production in developing countries. In present research, an attempt was made for carrying out nutrient budgeting, which includes the calculation of nutrient balance at micro (plot / field) and meso (farm) level and evaluation of trends in nutrient mining / enrichment. A nutrient budget is an...

Water quality in many stream catchments and river basins is severely impacted by nutrient enrichment as a result of agriculture. Water-resource managers worldwide are considering the potential role of riparian zones and floodplain wetlands in improving stream-water quality, as there is evidence at the site scale that such wetlands are efficient at removing nutrients from through-flowing water. ...

Developing integrated farming systems is critical to reducing the environmental impact of animal production. Traditionally, this has been through integrating animal and feed or plant production. But that has become increasingly difficult as agricultural production has become regionally specialized leading to the spatial separation of animal and feed production. This spatial separation has led t...

Stoichiometric nutrient ratios are the consequence of myriad interacting processes, both biotic and abiotic. Theoretical explanations for autotroph stoichiometry have focused on species' nutrient requirements but have not addressed the role of nutrient availability in determining autotroph stoichiometry. Remineralization of organic N and P supplies a significant fraction of inorganic N and P to...

This paper reviews nutrient deficiencies in agricultural crops of PNG using the literature of agronomic trials and field observations made throughout the country. Nutrient deficiencies have been investigated systematically since the mid-1950s, but research has mainly focused on export tree crops and relatively little information is available on food crops. Literature analysis and field observat...

Extensive network of tile drains present in the Midwest USA accelerate losses of nutrients to receiving ditches, rivers and eventually to the Gulf of Mexico. Nutrient inputs from agricultural watersheds and their role in affecting water quality have received increased attention recently; however, benthic sediment-nutrient interactions in tile-fed drainage ditches is still a matter of active res...

Clearfelling and downhill, skyline-hauler extraction of pulpwood and sawlogs in beech-podocarp-hardwood (PB5) forest, followed by slash-burning, produced increased streamflow yields of N, P arid dissolved cations. Nutrient outputs in the first four months after treatment were from 1 to' 1.5 times the normal annual output. Yields of Na, Mg, Ca, and K were from 1 to 6 times the normal output; K o...

[1] Hydrologic losses can play a key role in regulating ecosystem nutrient balances, particularly in regions where baseline nutrient cycles are not augmented by industrial deposition. We used first-order streams to integrate hydrologic losses at the watershed scale across unpolluted old-growth forests in New Zealand. We employed a matrix approach to resolve how stream water concentrations of di...

Land application of sewage sludge requires careful monitoring because of its potential for contamination of surface water and ground water. A rainfall simulator was used th investigate the effects of freshly applied sludge on infiltration, and on runoff of sediment and nutrients from agricultural crop lands. Rain was applied to 16 experimental field plots. A three-run sequence was used to simul...