Study On Four Kinds Of Typical System On Productivity And Water Utilization In Agro-pastoral Ecotone In Inner Mongolia

Agro-pastoral ecotone is an ecological environment transitional belt and an important ecological safety barrier.Agro-pastoral ecotone researches focuses on both ecological recovery and land productivity under the circumstances of climate drought and environmental degradation.Intercropping improves agricultural production and resources use efficiencies,especially water use efficiency.This research mainly analysed the yield?crop water consumption and water use efficiency of 4 typical intercropping systems:(sunflower/potato ?sunflower/fababean?oats/potato?oats/fababean)in agro-pastoral ecotone in inner Mongolia comparing with sole crop.FST intercropping model was used to simulate the soil moisture content and transpiration of component crops in the intercropping.The main conclusions were:(1)2S2P system is better than 6O2 P to improve potato's plant height,6O2 P is better than 2S4 F to improve fababean's plant height.Potato's leaf area index can be improved in 2S2 P.Oats' leaf area index can be improved significantly in 6O6 F,and fababean has advantage in 2S4 F system.Sunflowers' dry matter in 2S4 F has advantage over in 2S2 P.High stalk crop has advantages in intercropping systems,the development condition is much better than it was in monoculture system.(2)The high stalk crops' dry matter and yield all show advantages.Sunflower's yield can be improved significantly in 2S2 P and 2S4 F systems,potato's yield can be seriously influenced in 6O2 P system,oats' yield has advantages in both 6O2 P and 6O6 F systems,fababean's yield in intercropping has not been improved.The high stalk crop's yield has advantages in intercropping systems.The four kinds of intercropping systems are all can raise land equivalent ratio,show the intercroppping advantages and economic benefits.(3)Intercropping system increased crop water consumption compared with the monocultures,by utilizing more deep soil layer's water.Sunflower in intercropping systems almost has no change;potato water consumption can be effectively improved in 2S2 P and 6O2P;oats water consumption can be increased in the intercropping system,fababeans' water consumption has no advantages in the intercropping systems.2S2 P system is helpful for crop for water consumption from 0 to 60 cm soil layers,effectively increase the whole field water consumption,oats' water consumption has advantages in 6O2 P.The potato's water consumption in growth period can be significantly increased in 2S2 P system,but has no significant difference on seedling stage;oats' water consumption in seedling stage and potato's water consumption in flowering stage can be significantly increased in 6O2 P.(4)The WUE of sunflower was increased by 27.1% in 2S2 P system,and increased by 28.8% in 2S4 F,the WUE of oat was increased by 33.3% in 6O2 P system.Four kinds of intercropping system can all effectively improve the water use efficiency of high stalk crops,short crops' water use efficiency is slightly lower,intercropping system can increase the water equivalent ratio on the whole,the water equivalent ratio of 2S2 P and 2S4 F system is both above 1.2,so the two intercropping systems all have water use efficiency significantly,2S4 F system has best advantages in all.(5)Simulated transpiration and water use efficiency by using the intercropping model in 2S2 P,showed a good result.The results on transpiration of 2S2 P showed that crop transpiration is high in mid-growth stage.Intercropping improved crop transpiration and water use efficiency effectively.