检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
机构地区:[1]清华大学水利水电工程系,北京100084 [2]山西潇河水利管理局,山西榆次030600
出 处:《节水灌溉》2006年第1期1-4,8,共5页Water Saving Irrigation
基 金:国家自然科学基金项目(50179017);国家高技术研究发展计划("863"计划)节水农业专项(2002AA2Z4311)
摘 要:在最小二乘回归失效的情况下,将偏最小二乘回归应用于山西潇河灌溉试验站冬小麦水肥生产函数建模。该方法可以克服多重相关引起的危害,建立合理的、具有较强的稳定性和预测能力的水、氮、磷生产函数模型。由模型分析可知,水、氮、磷三因素都具有明显的增产效应。水肥耦合效应表现为水肥对产量的协同作用和氮、磷之间的竞争关系。随着作物耗水量的增加,氮、磷的利用效率得到提高;而增加氮、磷投入亦能提高水分利用效率。此外,还提出了氮、磷有效组合区域的概念。Partial least-squares regression is applied in modeling of fertilizer-water production function of winter wheat in Xiaohe irrigation station, Shanxi province when least-squares regression fails and then the water nitrogen phosphor production model of 2002~2003 is acquired. The simulation result justifies that partial least-squares regression can solve the problems caused by multicollineari ty in multi-regression and the model established is reasonable. According to it, the production-increasing effect of evapotranspiration, nitrogen and phosphor is remarkable. The coupling effect between water and fertilizer manifests that they can boost the production increasing effect mutually. Water use efficiency will increase when the nitrogen and phosphor are increased and vice versa. Fertilizer use efficiency will decrease when nitrogen and phosphor are increased. And nitrogen and phosphor are competitive to some degree. In addition, a so called conception "effective compounding zone of nitrogen and phosphor" is presented in this paper.
关 键 词:偏最小二乘回归 最小二乘回归 多重相关性 水肥生产函数
分 类 号:S114[农业科学—农业基础科学]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:3.133.158.178