Soil e ro sion is an important formof nonpoint source pollutions.Different patters of lan d use may have signi ficant effects
on soil erosion and results in losses of nit rogen and phosphorus.This work was conducted to determine relationship between different
vegetation covers with sediments an d nitrogen and phosphorus losses .We selected four small representative watersheds in Jiulong River to conduct t he present researc h.From May to August of 2003,series o f water samples w ere collected from 4sub-watershed drainage outlets in each rainfall event,an d in the meantime,flow rate of the rum off was also measured.Total nitrogen(T N),total dissolved nitrogen(TDN),total phosphorus(TP),total dissolved ph osphorus(TDP)and suspend sediment (SS)were measured for the samples.The res ults obtained sh owed as follows:the order of sedimen t yields and losses of ni trogen and phosphorus in the small watersheds was in an order:orchard>>farm> manpower forest>natural forest.And the more the vegetation cove rs,the smalle r the nitrogen and phosphorus losses.Sediments and runoff by which nutrie nts w ere lost had the same trend durin g the rainfall period.Total dissolved nitroge n(TDN)was the major form of nitrogen loss in runoff and total particulate phos ph orus(TPP)was the major form of
phosphorus loss in runoff.