温室栽培中秸秆还田方式对作物生长及土壤碳氮的影响

为了探讨温室作物栽培中秸秆应用对作物生长和土壤肥力的影响，设传统耕作（CK）、秸秆覆盖地表（S）和秸秆掩埋到地下20 cm（I）3 个处理。结果表明：S 处理能显著提高南瓜叶片对光合有效辐射的响应。在小麦生长初期，各处理地上部和地下部生物量的大小均为S ＞ I ＞ CK，随着时间推移，I处理呈现减产的趋势。I 处理的小麦根总长、根表面积、根体积、根直径和叶面积均显著低于S 处理。S处理持续提高了土壤总碳含量，播种2 个月后比初始值升高了41.87%；I 处理和对照在小麦生长初期土壤总碳含量增加，但播种2 个月后土壤总碳含量开始减少，I 处理的土壤总碳含量比初始值降低8.87%。在小麦播种1 个月后I 处理和对照土壤总氮含量均有所提高，播种2 个月后3 个处理的土壤总氮含量均低于初始值。S 处理的碳氮比显著高于其他两个处理，有利于土壤碳的贮存。

Effects of Straw Returning Mode on Crop Growth and Soil Carbon and Nitrogen in Greenhouse Cultivation

In order to explore the effects of application of straw on crop growth and soil fertility in greenhouse vegetable cultivation，we designed 3 treatments as conventional tillage（ CK），straw mulch surface（ S） and straw buried into underground 20 cm deep（I）．The result showed that the S treatment could significantly improve the response of the blades to photosynthetically active radiation．In the early stage of crop growth，the biomass aboveground or underground of each treatment were r anked as S＞ I ＞CK．As time went by，I treatment presented a declining trend of yield．In I treatment，the total length of wheat root，root surface area，root volume，root diameter and leaf area were significantly lower than that in S treatment．S treatment sustainably improved the total soil carbon content，which was 41.87% higher than that of the initial value，2 months after sowing. In the initial wheat growing period， I and CK treatments were favorable for increasing the total carbon conte nt in soil．But，the total carbon content in soil started to decrease 2 months after sowing．In I treatment，it was 8.87% lower than the initial value.1 month after sowing the total nitrogen content in soil increased in I and CK treatments，while they were lower than the initial value 2 months later in 3 treatments．In a word，S treatment is beneficial for soil carbon storage as a result of higher carbon nitrogen ratio，which was significantly higher than the other 2 treatments.