模拟降雨条件下生物可利用磷在地表径流中的流失和预测  

BIOAVAILABLE PHOSPHORUS LOSS AND ITS PREDICTION IN RUNOFF UNDER SIMULATED RAINFALL CODITIONS

作　　者：晏维金[1] 章申[1] 吴淑安[1] 蔡强国[1] 唐以剑[1] 

机构地区：[1]中国科学院地理研究所,北京100101

出　　处：《环境化学》1999年第6期497-506,共10页Environmental Chemistry

基　　金：国家"九五"重大基金(批准号39790100);国家自然科学基金(批准号49801019)

摘　　要：本文通过模拟降雨径流实验,运用两种生物可利用磷（BAP）的化学浸提方法,在1.2mm·min^（-1）的大暴雨条件下,研究在施肥和未施肥两种情况下,BAP的径流流失方式和过程,并建立模型进行BAP的预测,结果表明,运用两种BAP的化学浸提方法测定的结果差异性不显著（p=0.05）,并具有1:1的线性相关关系;BAP的流失通过溶解态磷（DP）和颗粒态生物可利用磷（BPP）两种形态方式,随着降雨径流时间的延长,累积的BAP量呈对数式增加,径流流失的BAP量约占总磷量的25—30%;施肥能增加DP和BAP的流失量;通过模拟实验建立了BAP的预测模型: BAP=DP+BPP [DP]=（0.035×P_O×SL×t^（-0.2）×W^（0.5））/V [BPP]=1.19BPP_（soil）×SL并检验了BAP的预测结果无显著差异（p=0.05）。The loss of bioavailable phosphorus (BAP) from agricultural soil to surface waters in runoff can accelerate the eutrophication of receiving waters. BAP represents P that is potentially available for algal uptake. Therefore, the study on loss of BAP and its prediction would provide a more reliable assessment of the impact on surface water quality than just dissolved P (DP) or total P ( TP) . The loss of BAP (estimated by NaOH extraction) in DP and bioavailable particulate P (BPP) (estimated by NaOH extraction) forms were determined in a rainfall simulation experiment with a constant rainfall rate of 1.2mm·min-1 for 44 minutes period under unfertilized and fertilized conditions. The research showed that there is no significant difference between two chemical extraction methods of BAP measurement (p = 0.05), and the BAP values closely followed a 1 : 1 relationship. The results demonstrated that both concentrations of DP and BPP decreased, while the accumulated amount of BAP increased logarithmically along with runoff time. BAP comprised a larger portion of TP loss (ranging from 25-30%) for both fertilized and unfertilized conditions. However, DP and BAP loss in runoff increased by fertilizer application. Measured and predicted DP and BPP concentrations were similar in different period of runoff. Calculated as the sum of DP and BPP, BAP loss in runoff was predicted accurately, with only an 18% error in measured mean va -lue.Two equations were built to predict the loss of both DP and BPP by using kinetic and enrichment ratio approaches, respectively.[DP] = (0.035×P0×SL×t-0.2×W0.5) /V[BPP] =1.19BPPsoil×SLInclusion of these equations in comprehensive water quality models will improve the prediction of agricultural activity on the impact of receiving water bodies.

关 键 词：生物可利用磷 模拟降雨 预测方程 径流流失 

分 类 号：X52[环境科学与工程—环境工程] X592