Lake water eutrophication has become one of the most important factors impeding sustainable economic development in China. Knowledge of the current status of lake water eutrophication and determination of its mechanism are prerequisites to devising a sound solution to the problem. Based on reviewing the literature, this paper elaborates on the evolutional process and current state of shallow in...

Food production in Europe is dependent on imported phosphorus (P) fertilizers, but P use is inefficient and losses to the environment high. Here, we discuss possible solutions by changes in P management. We argue that not only the use of P fertilizers and P additives in feed could be reduced by fine-tuning fertilization and feeding to actual nutrient requirements, but also P from waste has to b...

Studies have demonstrated some P loss reduction following implementation of remedial strategies at field scales. However, there has been little coordinated evaluation of best management practices (BMPs) on a watershed scale to show where, when, and which work most effectively. Thus, it is still difficult to answer with a degree of certainty, critical questions such as, how long before we see a ...

The long-term ecological response to recurrent deforestation associated with shifting cultivation remains poorly investigated, especially in the dry tropics. We present a study of phosphorus (P) dynamics in the southern Yucatán, highlighting the possibility of abrupt shifts in biogeochemical cycling resulting from positive feedbacks between vegetation and its limiting resources. After three cul...

We carried out a one year (2002) study of phosphorus (P) loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 h...

Field trials were established to compare alum-treated poultry litter (ATPL), normal poultry litter (NPL), and triple superphosphate (TSP) as fertilizer sources for corn (Zea mays L.) when applied at rates based on current litter management strategies in Virginia. Trials were established in the Costal Plain and Piedmont physiographic regions near Painter and Orange, VA, respectively. Nitrogen-ba...

A measure of soil P status in agricultural soils is generally required for assisting with prediction of potential P loss from agricultural catchments and assessing risk for water quality. The objectives of this paper are twofold: (i) investigating the soil P status, distribution, and variability, both spatially and with soil depth, of two different first-order catchments; and (ii) determining v...

Temperature dependant mineralization dynamics during fire of litter species characteristic of the New Jersey pine barrens was determined. Senescent leaf material of pitch pine (Pinus rigida), white oak (Quercus alba) and black huckleberry (Gaylusssacia baccata) were collected at the time of abscission; sorted, ground and oven-dried at 70 8C. Replicate samples were then heated for 2 h at: 70, 10...

1. The quantitative variations of the concentrations of uric acid, citrate, nucleic acids and total and acid-soluble phosphorus in the pupal haemolymph of Philosamia ricini during metamorphosis have been studied. 2. The mean value for total nitrogen in the haemolymph and total loss in weight of the insects during metamorphosis have also been recorded.