以塔里木河流域为例，对天然绿洲和人工绿洲面积进行遥感解译，设置灌溉面积扩张（现实）和维持不变（理 想）两种实例，对比分析 1990—2020 年平原绿洲耗水平衡和用水效率，从灌溉面积扩张视角对灌溉效率悖论成因 进行探讨。结果表明：现实实例下，36 亿 m3净节水量被用于扩大灌溉面积，人工和天然绿洲耗水比从 4∶6 转变 为 6∶4，产生了严重的灌溉效率悖论；理想实例下，人工和天然绿洲耗水比维持在 4∶6，产生真实节水量 24 亿 m3， 可避免灌溉效率悖论的产生。灌溉效率悖论的产生是连续丰水年出现、节水技术推广、种植结构调整和灌溉面 积扩张等因素综合作用的结果，30 年来灌溉面积扩张对塔里木河流域灌溉效率悖论的产生起主导作用。

Agricultural?water?consumption?accounts?for?over?70%?of?the?world's?water?consumption.?For?a?long time,?promoting?water-saving?irrigation?technology?and?improving?agricultural?water?efficiency?have?been?regarded as?effective?methods?to?reduce?agricultural?water?consumption?and?alleviate?regional?water?scarcity.?However,?an increasing?number?of?studies?have?shown?that?with?the?application?of?water-saving?technology?and?the?improvement of?water-saving?levels,?the?shortage?of?water?resources?worldwide?has?become?even?more?severe,?resulting?in?the paradox?of?irrigation?efficiency.?The?emergence?of?the?paradox?of?irrigation?efficiency?results?from?various?factors such?as?hydrology,?economy,?society,?institutions,?and?management,?and?the?expansion?of?irrigation?area?is?an important?reason?for?the?paradox.?Revealing?the?mechanism?of?the?paradox?of?irrigation?efficiency?is?the?basis?for improving?water?and?land?resources?management?in?the?river?basins.?Tarim?River?basin?is?located?in?an?inland?arid area?with?scarce?water?resources,?and?the?natural?ecology?is?very?fragile.?In?the?recent?comprehensive?management of?the?Tarim?River?basin,?nearly?half?of?the?investment?was?spent?on?water-saving?renovation?in?irrigation?areas. However, ?the ?expected ?results ?were ?not ?achieved. ?The ?expansion ?of ?irrigation ?area ?resulted ?in ?the ?widespread phenomenon?of?"reclaiming?land?while?controlling"?and?"saving?water?while?consuming?water".?Under?the?condition of?a?certain?amount?of?total?water?resources,?there?is?a?game?competition?relationship?between?natural?and?artificial systems?regarding?water?consumption.?Therefore,?it?is?urgent?to?explore?the?evolution?of?water?consumption?with water ?use ?efficiency ?in ?water-saving ?development ?between ?natural ?oasis ?ecosystems ?and ?artificial ?oasis ?socio- economic?systems. ??????The?Tarim?River?basin,?the?most?apparent?contradiction?in?water?and?land?resources,?was?taken?as?an?example. The?rapid?development?of?water-saving?technology?from?1990?to?2020?was?selected?as?the?study?time.?Under?the conditions?of?consistent?water?resources,?social?economy,?and?water-saving?levels?in?the?basin,?two?cases?was?set?up, i.e.,?the?actual?case?with?irrigation?area?expansion?and?the?ideal?case?with?irrigated?area?maintenance.?The?basin’s water?consumption?and?water?use?efficiency?varying?with?the?development?of?water-saving?irrigation?were?analyzed and?compared?with?the?two?cases. ??????The?results?show?that?in?the?past?30?years,?the?irrigation?water?use?efficiency?of?the?basin?has?increased?from?0.28 to?0.55,?the?gross?irrigation?quota?has?been?reduced?by?twice,?and?the?water-saving?level?has?been?significantly improved.?In?the?actual?case,?3.6?billion?m3?of?net?water?savings?have?been?used?to?expand?irrigation?area,?resulting in?more?than?doubling?of?irrigation?area?and?water?consumption.?The?area?ratio?of?artificial?and?natural?oases?has changed?from?40∶60?to?55∶45,?and?the?water?consumption?ratio?has?changed?from?4∶6?to?6∶4.?The?proportion of?oasis?water?consumption?to?water?resources?has?increased?from?72%?to?91%,?resulting?in?a?severe?paradox?of irrigation?efficiency.?In?the?ideal?case,?the?irrigation?water?consumption?is?reduced,?the?area?and?water?consumption ratio?of?artificial?and?natural?oases?are?maintained?at?around?4∶6,?and?the?proportion?of?oasis?water?consumption?to water?resources?is?70%,?resulting?in?an?actual?water?saving?of?2.4?billion?m3,?avoiding?the?occurrence?of?the?paradox of?irrigation?efficiency. ??????The?emergence?of?the?paradox?of?irrigation?efficiency?is?the?complete?result?of?factors?such?as?great?water conditions,?water-saving?development,?planting?structure?adjustment,?and?irrigation?area?expansion.?In?the?past?30 years,?the?expansion?of?the?irrigation?area?has?played?a?leading?role?in?the?emergence?of?the?paradox?of?irrigation efficiency?in?the?Tarim?River?basin.?In?order?to?avoid?the?occurrence?of?the?paradox?of?irrigation?efficiency,?it?is necessary?to?manage?water?resources?strictly,?adhere?to?the?principle?of?"water?settling?land",?and?promote?the balanced?development?of?soil?and?water?resources?in?arid?inland?river?basins.