基于遗传算法的田间尺度土壤水力参数与溶质运移参数优化  

Optimization of soil hydraulic and solute transport parameters using genetic algorithms at field scale

作　　者：徐旭[1,2] 屈忠义[3] 黄冠华[1,2] 

机构地区：[1]中国-以色列国际农业研究培训中心,北京100083 [2]中国农业大学水利与土木工程学院,北京100083 [3]内蒙古农业大学水利与土木建筑工程学院,内蒙古呼和浩特010018

出　　处：《水利学报》2012年第7期808-815,共8页Journal of Hydraulic Engineering

基　　金：国家自然科学基金(51069006;5079106);中央高校基本科研业务费专项资金项目资助(项目编号:2011JS122);十二五国家科技支撑计划课题资助;公益性行业科研专项(200901083)

摘　　要：合理确定田间尺度土壤水力参数和溶质运移参数是保证农田土壤水盐动态模拟正确性的重要前提。本文开展了基于遗传算法(Genetic Algorithms,GA)与农田水文模型SWAP(Soil-Water-Atmosphere-Plant)耦合进行土壤水力参数和溶质运移参数优化的方法研究。在已有GA基础上引入了子体优生策略,并以完全嵌入方式耦合GA与SWAP模型。采用河套灌区曙光实验站的土壤剖面分层含水率(θi)和溶液浓度(cmli)、表土含水率(θsur)、实际腾发量(ETa)等观测资料,开展了田间尺度土壤水力参数和溶质运移参数优化的数值试验与相应分析。结果表明:(1)采用土壤分层信息(θi和cmli)作为观测数据,GA参数优化效果很好;(2)仅采用ETa作观测数据时,参数优化效果相对欠佳,需慎重使用,而结合ETa与θsur后可提高优化精度;(3)引入子体优生策略可提高GA的参数优化效率和精度。综上,结合GA与SWAP模型是优化田间尺度土壤水力参数和溶质运移参数的一种实用方法。Reasonable determination of soil hydraulic and solute transport parameters is significant for the simulation and prediction in vadose zone modeling. In this study, an inverse method was developed by ful- ly coupling the genetic algorithms （GA） and SWAP model （Soil-Water-Atmosphere-Plant） to solve the soil hydraulic and solute transport parameters. An operator called eugenics was introduced for improving the oper- ational efficiency of GA. A vadose zone model was constructed using SWAP for the Shuguang Experiment Station in Hetao Irrigation District, which could be used for simulating water flow and solute transport. Based on this model, ten numerical experiments were proposed for testing the applicability of the coupling of GA and SWAP model in inverse estimation of soil hydraulic and solute transport parameters. The soil wa- ter content, actual evapotranspiration, solute concentration or their combination were considered as the ob- served information for the inverse problems. Results indicate that it was feasible and efficient to use this ful- ly coupled GA and SWAP model to inversely estimate the soil hydraulic and solute transport parameters for practical field application at a field scale.

关 键 词：土壤水力参数 溶质运移参数 SWAP模型 遗传算法 参数反求 

分 类 号：S271[农业科学—农业水土工程]