邹雨坤　李光义等

摘 要：应用网袋法研究不同还田方式下香蕉茎秆的腐解及养分释放特征。结果表明：不同还田方式下，香蕉茎秆在0～30 d腐解速度快，30 d时，覆土、覆土覆膜和仅覆膜处理下质量累积减少率分别为60.6%，71.9%，77.6%；在180 d时，香蕉茎秆的质量累积减少率分别为86.4%，95.6%，91.0%，表现为覆土覆膜>覆膜>覆土。腐解过程中，覆土覆膜和仅覆膜处理下香蕉茎秆养分的释放速率表现为K>P>N≈C。180 d时，碳、氮、磷、钾的累积释放率均达到80%以上。考虑香蕉茎秆还田养分的释放情况，可以适量减少基肥中钾肥用量，如果采用短期还田，建议使用仅覆膜的方式，如果长期还田建议使用覆土覆膜的方式。

关键词：香蕉茎秆；还田方式；腐解特征；养分释放特征

中图分类号：S668.1 文献标识码：A DOI 编码：10.3969/j.issn.1006-6500.2014.10.013

Characteristics of Decomposing and Nutrients Releasing of Banana Stalk under Different Ways Returned to Field

ZOU Yu-kun， LI Guang-yi， LI Qin-fen， LI Yun-ting，TIAN Lu-yuan， ZHANG Hong-yan， HOU Xian-wen

（1.Environment and Plant Protection Institute， Chinese Academy of Tropical Agriculture Sciences， Haikou，Hainan 571101， China； 2.Danzhou Scientific Observing and Experimental Station of Agro-Environment， Ministry of Agriculture， Danzhou，Hainan 571737， China）

Abstract： Net bags were employed to research characteristics of decomposing and nutrients releasing of banana stalk under different ways returned to field. The results showed that banana stalk had fast decomposing speed during 0 to 30 days under different ways returned to field. Under covered with soil， covered with soil and plastic film and covered with plastic film only， the accumulated decay rate was 60.6%，71.9%，77.6% respectively at the 30th day， the accumulated decay rate was 86.4%，95.6%，91.0% respectively at the 180th day， and was ranked as： covered with soil and plastic film>covered with soil>covered with plastic film only. Releasing speed of nutrients of banana stalk ranked as： potassium > phosphorus >nitrogen≈carbon under covered with soil and plastic film and covered with plastic film only. The accumulated releasing rate of carbon， nitrogen， phosphorus and potassium was above 80%. The content of potassic fertilizer in base manure consideration of nutrients releasing could be reduced. And it is suggested that using the way of covered with plastic film only in a short term and the way of covered with soil and plastic film in a long term when banana stalk to field were returned.

Key words： banana stalk； the way returned to field； characteristics of decomposing； characteristics of nutrients releasing

秸秆安全还田技术，可改善土壤团粒结构和理化性状，提高土壤肥力，增加作物产量，节约化肥用量，是发展生态农业的一项重要措施。作物秸秆在土壤中腐解并释放养分是一个复杂的过程，其腐解及养分释放速率是评价秸秆还田后增加和改善土壤有机质及土壤肥力的重要指标[1]，国内外学者针对不同作物秸秆还田及其养分释放规律的研究已经做了一些工作，已研究了包括豌豆[2]、燕麦[2]、大豆[3]、玉米[4]、小麦[5]、油菜[5]等作物秸秆还田后养分的释放规律。以往的研究主要是针对温带、寒温带地区重要的粮食作物，而热带地区具有丰富的光、温、水条件，农业生产具有生物量大、农业废弃物含水量高等特点，且农业废弃物的利用率低，闲置状况严重，但关于热区作物秸秆还田及养分释放规律的研究还未见报道。endprint……