Fertilizer management in watersheds of two Ramsar wetlands and effects on quality of inflowing water.
Two field experiments were carried out in the watersheds of two Ramsar wetland areas, Lakes Koronia and Volvi (area A) and Lakes Mikri and Megali Prespa (area B), to study the effect of application of N fertilizer on wheat yields, the quality of runoff water, and the quality of stream water. The treatments were a combination of two methods of fertilizer application (total amount in fall, and 2/3 in fall + 1/3 in spring) at three rates (0, 100, and 200 kg N/ha) with four replications. Concentrations of NH4+, NO3-, NO2-, P, and Cl- and pH were determined in all water samples. Runoff water quality was not influenced by fertilizer application in either area. Chemical parameters for water did not differ along the selected watercourses in area B, while in area A they were higher in the samples taken near Lake Koronia than in the samples taken upstream, indicating that the watercourses are polluted downstream by nonagricultural sources. The differences in wheat yields between the 100 and 200 kg N/ha application rates were not high. These results call for better fertilizer management in order to achieve better yields and to diminish the possibility to have negative effects to the environment.
Tsiouris
S E
SE
Laboratory of Ecology and Environmental Protection, School of Agriculture, Aristotle University of Thessaloniki, 540 06 Thessaloniki, Greece. tsiouris@agro.auth.gr
Mamolos
A P
AP
Kalburtji
K L
KL
D000383:Agriculture; D004784:Environmental Monitoring; D005308:Fertilizers; D011786:Quality Control; D011891:Rain; D014908:Triticum; D014872:Water Movements; D014876:Water Pollution / Q000517:prevention & control*
D005308:Fertilizers