水稻秸秆生物炭对江汉平原麦区小麦养分吸收和产量的影响

旨在探明水稻秸秆生物炭施用量和施用时期对江汉平原稻茬麦养分吸收、土壤养分含量以及产量的影响。选择江汉平原典型潮土稻麦轮作区,以基施化肥但不施生物炭处理为对照,设置小麦播种前基施、返青拔节期追施以及两个时期同施不同剂量的生物炭等处理,采用比色法和火焰光度计法测定了不同处理小麦籽粒、植株茎叶和土壤的氮、磷、钾含量,并比较了籽粒产量的变化。结果表明,施用生物炭促进了小麦籽粒和植株茎叶对氮、磷、钾元素的吸收,增加了地上部分氮、磷、钾养分吸收总积累量,且以基施及追施13500 kg/hm²生物炭处理最高,较对照处理籽粒总氮、磷、钾分别提高了20.3%、17.8%和12.4%,茎叶总氮、磷、钾分别提高了11.9%、34.5%和13.9%,氮、磷、钾总积累量显著增加18.2%、24.0%、13.7%(P<0.05);施用生物炭后土壤pH升高、有机质和速效磷含量增加,小麦株高增高,结实率和千粒重增大。施用水稻秸秆生物炭对于改善土壤和提高小麦产量具有一定促进作用。

Rice Straw Biochar: Effects on Nutrient Absorption and Yield of Wheat in Jianghan Plain

The study aims to reveal the effects of rice straw biochar application amount and time on nutrient absorption, soil nutrient content and yield of wheat after rice in Jianghan Plain. The typical fluvo-aquic area of rice-wheat rotation in Jianghan Plain was selected, and the basal application of chemical fertilizer with no biochar was used as the control. The treatments were set up, including the application before wheat sowing, topdressing at jointing stage, and different-amount biochar application at both of the stages. The wheat grains, plant stems and leaves, and the content of nitrogen, phosphorus and potassium in soil were detected with colorimetry and flame photometer methods. The grain yields were also compared. The results showed that the application of biochar could promote the absorption of nitrogen, phosphorus and potassium in wheat grains, plant stems and leaves, and increase the total accumulation of nitrogen, phosphorus and potassium in above ground plant parts. The highest values appeared when the basal and topdressing application of biochar was 13500 kg/hm². Compared with the control, the total content of nitrogen, phosphorus and potassium in grain were increased by 20.3%, 17.8% and 12.4%, respectively, the total content of nitrogen, phosphorus and potassium in stems and leaves were increased by 11.9%, 34.5% and 13.9%, respectively, while the total accumulation of nitrogen, phosphorus and potassium were increased significantly by 18.2%, 24.0% and 13.7% (P < 0.05), respectively. After biochar application, the soil pH, organic matter and available phosphorus content were increased, and wheat plant height, seed setting rate and 1000-grain weight were improved. The application of rice straw biochar can promote soil condition and wheat yield.