水利水电技术
水利水電技術
수이수전기술
WATER RESOURCES AND HYDROPOWER ENGINEERING
2010年
2期
60-64
,共5页
农业节水%评价%水分生产率%边际产量%基准产量%基准定额
農業節水%評價%水分生產率%邊際產量%基準產量%基準定額
농업절수%평개%수분생산솔%변제산량%기준산량%기준정액
agricultural water-saving%evaluation%water productivity%marginal yield%basic yield%basic quota
文中归纳了各种反映农业节水水平的指标体系,分析了各指标之间存在的内在联系,并以数学解析方法,描述了主要指标之间的数学关系式及基本线型.通过推求灌溉水的水分生产率~边际产量关系曲线(Z_1曲线)的最大值,确定符合农业节水要求的产量阈值下限和定额阈值下限,即基准产量和参考定额;以Z_1曲线为基础,叠加节灌粮食产量~产量期望值关系曲线(Z_2曲线)形成Z曲线,通过推求其极值,确定符合农业节水要求的定额阈值上限和产量阈值上限,即基准定额和参考产量.根据这种方法,可以将复杂问题简单化,通过定量计算,对一个区域进行定性节水水平评价.
文中歸納瞭各種反映農業節水水平的指標體繫,分析瞭各指標之間存在的內在聯繫,併以數學解析方法,描述瞭主要指標之間的數學關繫式及基本線型.通過推求灌溉水的水分生產率~邊際產量關繫麯線(Z_1麯線)的最大值,確定符閤農業節水要求的產量閾值下限和定額閾值下限,即基準產量和參攷定額;以Z_1麯線為基礎,疊加節灌糧食產量~產量期望值關繫麯線(Z_2麯線)形成Z麯線,通過推求其極值,確定符閤農業節水要求的定額閾值上限和產量閾值上限,即基準定額和參攷產量.根據這種方法,可以將複雜問題簡單化,通過定量計算,對一箇區域進行定性節水水平評價.
문중귀납료각충반영농업절수수평적지표체계,분석료각지표지간존재적내재련계,병이수학해석방법,묘술료주요지표지간적수학관계식급기본선형.통과추구관개수적수분생산솔~변제산량관계곡선(Z_1곡선)적최대치,학정부합농업절수요구적산량역치하한화정액역치하한,즉기준산량화삼고정액;이Z_1곡선위기출,첩가절관양식산량~산량기망치관계곡선(Z_2곡선)형성Z곡선,통과추구기겁치,학정부합농업절수요구적정액역치상한화산량역치상한,즉기준정액화삼고산량.근거저충방법,가이장복잡문제간단화,통과정량계산,대일개구역진행정성절수수평평개.
Various index systems of agricultural water-saving levels are summarized herein; for which an analysis is made on the inherent relations among all the indexes, and then the mathematical relationships with the basic linetypes among the main indexes are described with mathematical analytical method. Through calculating the maximum value of the relationship curve between the water productivity~the marginal yield (Z_1 curve) of irrigation water, both the lower limit of the yield threshold and the lower limit of the quota threshold, i.e. the basic yield and the basic quota, conformed with the requirement of agricultural water-saving are determined. Furthermore, based on the Z_1 curve, the Z curve is formed by adding the relationship curve of the grain yield from the water saving irrigation~the expected value of the yield (Z_2 curve), thus, the lower limit of the yield threshold and the lower limit of the quota threshold, i.e. the basic quota and the reference yield, conformed with the requirement of agricultural water-saving are determine through the calculation of its extreme value. With this method, the qualitative evaluation on the water-saving level of a region can be made by solving a complicated problem through a simplified way on the basis of the quantitative calculation concerned.