西南地区不同套种模式对土壤肥力及经济效益的影响

为探讨不同作物组合的种植模式对土壤肥力及经济效益的影响,寻找作物搭配合理、低投入高产出的套作模式。采用单因素随机区组试验,研究比较了4种套作模式(小麦/玉米/大豆、小麦/玉米/甘薯、小麦/高粱/大豆、马铃薯/玉米/大豆)的土壤肥力、产量及经济效益的差异。连续种植3年后,各种植模式的土壤养分含量基本维持或得到提升(速效钾除外)。甘薯茬口对全钾、速效钾消耗均较大,需适当提高钾肥用量。小麦/玉米/甘薯的总产量最高,小麦/玉米/大豆模式的大豆单产量最高,小麦的单产各模式无显著差异。不同模式收益表现为,小麦/玉米/大豆马铃薯/玉米/大豆小麦/玉米/甘薯小麦/高粱/大豆;产投比表现为,小麦/玉米/大豆马铃薯/玉米/大豆小麦/玉米/甘薯小麦/高粱/大豆。小麦/玉米/大豆收益为14196.41元/hm~2,产投比为3.69:1,均为所有模式中最高,加之大豆茬口可以活化土壤养分,是相对理想的套作模式。

Effect of Different Relay Intercropping Patterns on Soil Fertility and Economic Benefits in Southwest China

To explore the effect of different crop arrangements on the economic benefits and yearly soil fertility, and aims to find a low input and high output relay intercropping patterns. The research used a randomized complete block design experiment to research soil fertility, yield and economic benefit in four relay intercropping patterns (wheat/maize/soybean, wheat/maize/sweet potato, wheat/sorghum/soybean and potato/maize/soybean). The soil nutrient maintained or improved after planting for continuous three years (except available K); the sweet potato stubble absorbed a large amount of total K and available K, therefore, the application of K fertilizer should be increased; the wheat/maize/potato got the maximum total yield, while the wheat/maize/soybean got the maximum soybean yield. There was no significant difference of wheat yield. The economic benefits of different patterns showed wheat/maize/soybean>potato/maize/soybean>wheat/maize/sweet potato>wheat/sorghum/soybean. Compared with other relay intercropping patterns, wheat/maize/soybean achieved the highest economic benefit (14196.41 yuan/ha) and the highest output-input ratio (3.69:1), moreover, soybean stubble can activate soil nutrient, therefore, wheat/maize/soybean can be regarded as the best crop arrangement for relay intercropping.