果樹在係統發育中形成了對水分不同要求的生態類型
，一般而言，本身需水量少，且具有旱生形態性狀，如葉片小、全綠
、角質層厚
、氣孔少而下陷的果樹或具有強大根係的果樹
，抗旱力較強。按照抗旱能力和需水量不同，可將果樹分為以下3類：

1、抗旱力強的桃、扁桃

、杏、石榴、棗、無花果、核桃、鳳梨。

2
、抗旱力中等的蘋果
、梨
、柿
、櫻桃、李、梅、柑橘。

3、抗旱力弱的香蕉、枇杷、楊梅。

wulunyoushuhuojieguoshu，geqiguandehanshuiliangshibupinghengde，wangwangshichuyushengchangzuihuoyuedeqiguanhezuzhizhongdeshuifenhanliangjiaoduo。jieguoguoshichangchangshiheyepianzhengduoshuifenzuituchudeqiguan
，zaiqueshuiqingkuangxia，youxiangongyepianzhengteng，guoshichengqueshuizhuangtai，yingxiangguopindechanliangyupinzhi。

guoshuzaigegewuhouqiduishuifendeyaoqiubutong，xushuiliangyebutong
，tongchangluoyeguoshuzaichunjimengyaqian
，shutixuyaoyidingdeshuifencainengfaya
，ciqishuifenbuzu

，changyanchimengyaqihuomengyabuzhengqi，yingxiangxinshaoshengchang。huaqiganhanhuoshuifenguoduo，changyinqiluohualuoguo，jiangdizuoguolv。xinshaoshengchangqiwendujijushangsheng，zhiyeshengchangxunsuwangsheng
，xushuiliangzuiduo，duiqueshuifanyingzuimingan，weixushuilinjieqi。ruguogonggeibuzu，zexueruoshengchang，shenzhizaoqitingzhishengchang。huayafenhuaqixushuixiangduijiaoshao，ruguoshuifenguoduozexueruofenhua。cishizaibeifangzhengyaojinruyuji，ruyujituichi，zekecushitizaofenhua，yibanjiangyushiliangshibuyingguanshui。guoshifayuqiyexuyidingshuifen，danguoduoyiyinqihouqiluoguohuozaochenglieguo，yizaochengguoshibinghai，yingxiangchanliangjiguopinpinzhi。qiujiganhan，zhitiaoshengchangtizaojieshu，genxitingzhishengchang，yingxiangyingyangwuzhidejileihezhuanhua，xueruoyuedongxing，dongjiqueshuichangshizhigandongshang。

二、果樹的水分平衡和需水量   

所謂水分平衡是指果樹的蒸騰量和吸水量相近時的狀態。水分平衡是果樹生長發育的基礎，是灌水、排水
、提(ti)高(gao)果(guo)實(shi)品(pin)質(zhi)及(ji)產(chan)量(liang)的(de)科(ke)學(xue)依(yi)據(ju)。不(bu)論(lun)幼(you)樹(shu)還(hai)是(shi)結(jie)果(guo)樹(shu)，各(ge)器(qi)官(guan)的(de)含(han)水(shui)量(liang)是(shi)不(bu)平(ping)衡(heng)的(de)，一(yi)般(ban)是(shi)處(chu)於(yu)生(sheng)長(chang)最(zui)活(huo)躍(yue)的(de)器(qi)官(guan)和(he)組(zu)織(zhi)中(zhong)的(de)水(shui)分(fen)含(han)量(liang)較(jiao)多(duo)。但(dan)對(dui)果(guo)樹(shu)整(zheng)體(ti)來(lai)說(shuo)則(ze)在(zai)果(guo)樹(shu)生(sheng)長(chang)發(fa)育(yu)的(de)各(ge)個(ge)階(jie)段(duan)
，永(yong)遠(yuan)保(bao)持(chi)著(zhe)相(xiang)對(dui)的(de)水(shui)分(fen)平(ping)衡(heng)狀(zhuang)態(tai)。蒸(zheng)騰(teng)的(de)速(su)度(du)取(qu)決(jue)於(yu)小(xiao)氣(qi)候(hou)因(yin)素(su)
、植物的形態結構和生理類型。

果樹在生長季的蒸騰量與其所生成的幹物質的重量比稱為需水量，一般以形成幹物質所需的水量表示。果樹的需水量隨樹種
、土壤類型、氣候條件及栽培管理技術等不同而有差異。

果樹的需水量隨樹種、土壤類型、氣候條件及栽培管理的不同而不同，由於不同種類的果樹生理特征的差異，需水量也有一定的差異。一般而言
，葉片小、全緣
、角質層厚
、氣孔小而下陷的旱生形態果樹
，如石榴、扁桃
、無花果等需水量小，而葉片大的水生果樹需水量則較大。

wulunyoushuhuojieguoshu，geqiguandehanshuiliangshibupinghengde，wangwangshichuyushengchangzuihuoyuedeqiguanhezuzhizhongdeshuifenhanliangjiaoduo。jieguoguoshichangchangshiheyepianzhengduoshuifenzuituchudeqiguan，zaiqueshuiqingkuangxia
，youxiangongyepianzhengteng，guoshichengqueshuizhuangtai
，yingxiangguopindechanliangyupinzhi。

guoshuzaigegewuhouqiduishuifendeyaoqiubutong，xushuiliangyebutong，tongchangluoyeguoshuzaichunjimengyaqian，shutixuyaoyidingdeshuifencainengfaya
，ciqishuifenbuzu



，changyanchimengyaqihuomengyabuzhengqi
，yingxiangxinshaoshengchang。huaqiganhanhuoshuifenguoduo，changyinqiluohualuoguo，jiangdizuoguolv。xinshaoshengchangqiwendujijushangsheng，zhiyeshengchangxunsuwangsheng，xushuiliangzuiduo，duiqueshuifanyingzuimingan
，weixushuilinjieqi。ruguogonggeibuzu，zexueruoshengchang，shenzhizaoqitingzhishengchang。huayafenhuaqixushuixiangduijiaoshao
，ruguoshuifenguoduozexueruofenhua。cishizaibeifangzhengyaojinruyuji，ruyujituichi
，zekecushitizaofenhua，yibanjiangyushiliangshibuyingguanshui。guoshifayuqiyexuyidingshuifen，danguoduoyiyinqihouqiluoguohuozaochenglieguo，yizaochengguoshibinghai，yingxiangchanliangjiguopinpinzhi。qiujiganhan
，zhitiaoshengchangtizaojieshu，genxitingzhishengchang，yingxiangyingyangwuzhidejileihezhuanhua，xueruoyuedongxing
，dongjiqueshuichangshizhigandongshang。

果guo樹shu需xu要yao水shui分fen，但dan並bing不bu是shi水shui分fen越yue多duo越yue好hao

，有you時shi果guo樹shu適shi度du的de缺que水shui還hai能neng促cu進jin果guo樹shu根gen係xi深shen紮zha

，提ti高gao其qi抵di禦yu後hou期qi幹gan旱han的de能neng力li，抑yi製zhi果guo樹shu的de枝zhi葉ye生sheng長chang，減jian少shao剪jian枝zhi量liang，並bing使shi果guo樹shu盡jin早zao進jin入ru花hua芽ya分fen化hua階jie段duan，使shi果guo樹shu早zao結jie果guo，並bing提ti高gao果guo品pin的de含han糖tang量liang及ji品pin質zhi等deng。