农业工程学报
農業工程學報
농업공정학보
2013年
10期
116-122
,共7页
灌溉%GIS%水分%青稞%等值线%西藏
灌溉%GIS%水分%青稞%等值線%西藏
관개%GIS%수분%청과%등치선%서장
irrigation%GIS%moisture%highland barley%contour line%Tibet
西藏地区灌溉定额等试验数据有限,因此,基于少量实测数据,计算分析作物净灌溉定额及其空间变化规律,扩展有限数据的使用范围具有十分重要的意义.基于拉萨站实测的青稞作物系数,采用FAO提出的作物系数修正方法,得到西藏4个农业分区中代表站的青稞作物系数值.基于青稞种植区共28个站点的气象资料及4个分区的青稞作物系数及土壤水分参数等资料,采用土壤水量平衡原理计算得到28个站的青稞灌溉定额长系列值.采用克里金插值法得到西藏青稞不同水文年型灌溉定额及其主要影响因子的等值线图,分析了青稞灌溉定额的空间变化规律及其与主要影响因子的关系.结果表明,从西北到东南,青稞灌溉定额呈现逐渐减小的变化趋势,其等值线总体呈带状分布特点,并且等值线与经线趋于平行.青稞灌溉定额随着降雨量增加而降低,随气温及ET0增加而增加.
西藏地區灌溉定額等試驗數據有限,因此,基于少量實測數據,計算分析作物淨灌溉定額及其空間變化規律,擴展有限數據的使用範圍具有十分重要的意義.基于拉薩站實測的青稞作物繫數,採用FAO提齣的作物繫數脩正方法,得到西藏4箇農業分區中代錶站的青稞作物繫數值.基于青稞種植區共28箇站點的氣象資料及4箇分區的青稞作物繫數及土壤水分參數等資料,採用土壤水量平衡原理計算得到28箇站的青稞灌溉定額長繫列值.採用剋裏金插值法得到西藏青稞不同水文年型灌溉定額及其主要影響因子的等值線圖,分析瞭青稞灌溉定額的空間變化規律及其與主要影響因子的關繫.結果錶明,從西北到東南,青稞灌溉定額呈現逐漸減小的變化趨勢,其等值線總體呈帶狀分佈特點,併且等值線與經線趨于平行.青稞灌溉定額隨著降雨量增加而降低,隨氣溫及ET0增加而增加.
서장지구관개정액등시험수거유한,인차,기우소량실측수거,계산분석작물정관개정액급기공간변화규률,확전유한수거적사용범위구유십분중요적의의.기우랍살참실측적청과작물계수,채용FAO제출적작물계수수정방법,득도서장4개농업분구중대표참적청과작물계수치.기우청과충식구공28개참점적기상자료급4개분구적청과작물계수급토양수분삼수등자료,채용토양수량평형원리계산득도28개참적청과관개정액장계렬치.채용극리금삽치법득도서장청과불동수문년형관개정액급기주요영향인자적등치선도,분석료청과관개정액적공간변화규률급기여주요영향인자적관계.결과표명,종서북도동남,청과관개정액정현축점감소적변화추세,기등치선총체정대상분포특점,병차등치선여경선추우평행.청과관개정액수착강우량증가이강저,수기온급ET0증가이증가.
The objective of this study was to estimate the irrigation water quota and their spatial distribution of highland Barley in Tibet. Tibetan plateau has the characters of high altitude, low air pressure, vast geographic, and has significant differences on climate spatial distribution. Until now, Tibet has very few measured irrigation and drainage experiment data of crops. This paper tried to combine theoretical calculation and survey data together to find a method to calculate the irrigation water quota and obtain a contour map under different irrigation frequency in convenient for project design. Four represent highland barley planting sites in each of four agricultural growth partitions of Tibet were selected to get information on irrigation, cultivation, soil conditions and meteorological characteristics, then 28 meteorological stations’long series of climate data were gathered. To calculate the accurate irrigation water quota of Tibet highland barley, water balance method was applied to calculate daily water balance processes during the growth period. In this process, precipitation, effective precipitation, root zone soil moisture, evapotranspiration, percolation, drainage and so on factors were used. Root zone’s soil water was determined by scheming wetness depth and appropriate upper and lower soil moisture limit, and ETc(evapotranspiration) was determined by FAO. Kcini, Kcmid, Kcend were modified considering soil and crop evaporation separately by recommended dual crop coefficient. Kc of four typical sites were calculated, and then irrigation water quota from 1957 to 2009 were calculated by daily water balance in different hydrological years. By comparing the calculated results with surveyed irrigation data, four sites’calculated results were validated, and then the other 24 sites of the 4 partitions’irrigation water quota were also calculated. According to 28 sites’results, Kringing interpolation method was used to get the contour map of Tibet highland barley irrigation water quota in different hydrological years. Climate factors that may interpret irrigation water quota for highland barley were analyzed using Kringing method and contour maps were also obtained. Results showed, in general, from the northwest to the southeast, irrigation water quota decreased gradually. Highland barley irrigation water quotas in Tibetan decreased with precipitation and increased with temperature and ET0.