中国农田重金属污染趋势性预测和预报系统

The Tendency Prediction and Forecast System for Farmland Heavy Metal Pollution in China

中国农田重金属污染趋势性预测和预报系统建立的理论:预测是建立在不同时段的、农田重金属污染数据基础之上的、对未来时段农田重金属的估计,预报是针对突发事件对农田重金属短时间影响的推测。系统建立的方法是:根据重金属在土壤中持续积累的特点,将持续积累模型转化为时间模型,避开根据重金属来源进行预测和预报的困难;以土壤背景值为重要参数,分别建立只有1个时段、2个时段和3个时段监测数据的预测方法,每次可取不同时段的监测数据之差或求算与背景值之差作为污染速率;在有4个时段以上监测数据的情况下,采用时间步长为3～5 a的简单移动平均数法再建立回归模型;具体预测和预报时,在区域内按需要可以建立点污染和污染等级预测和预报模型;在建立预测和预报模型前,首先需要建立农田重金属污染历史数据集。应用结果表明:所提出的理论和方法是通用的,经过验证是可行的。

The system of tendency prediction and forecast for farmland heavy metal pollution： Prediction is the estimation of farmland heavy metal in a period of time in future and it is based on different period, mass of farmland pollution datas while forecast is prediction of effect on farmland soil by emergency events in a short time.The system established method： Translate constantly accumulate model into time model according to the character of heavy metal constantly accumulate in soil and it avoids the difficulty of prediction and forecast according to the source of pollutants; establish prediction method of monitoring data in only one time section, two time sections and three time sections sepa- rately under the condition that soil background value is the main index. Each time the difference of monitoring data in different time sections or the difference between monitoring data with background data could be selected as pollution rate; for more than four time sections monitoring datas, moving average method by taking three to five years as step length could be used to establish regression model; prediction and forecast model of point pollution and pollution level could be established in area when concrete prediction and forecast be made; before making prediction and forecast models, farmland pollution history dataset must be established first. The application consequence shows： The theory and method are universal and viable.