秸秆深还年限对葡萄园土壤腐殖质组分及酶活性的影响
摘要：通过在葡萄园设置2年田间定位试验，研究了CK（秸秆不还田）、SRF1（秸秆还田并深埋1年）和SRF2（秸秆还田并深埋2年）3个处理下耕层土壤的腐殖质组分碳含量、酶活性及养分含量等指标变化，旨在探明秸秆还田对土壤腐殖质碳组分和土壤酶活性的影响。结果表明，与CK相比，SRF1和SRF2处理土壤腐殖质碳含量分别增加25.8%和31.6%，且均明显提升了土壤的PQ（胡敏酸碳与腐殖质碳的比值）和胡富比（胡敏酸碳与富里酸碳的比值）；秸秆还田显著提高了土壤酶活性，与CK相比，SRF1和SRF2处理土壤脲酶活性分别增加42.4%和60.6%，酸性磷酸酶活性分别增加9.2%和10.5%，蔗糖酶活性分别增加28.1%和30.6%。与CK相比，SRF1和SRF2处理土壤pH分别由5.86提升至6.48和6.79；秸秆还田后土壤有机质、碱解氮、有效磷、速效钾、有效锌、有效硼和有效铁含量均显著增加，且随还田年限的延长而增加。通过对土壤腐殖质碳组分和土壤酶活性进行相关性分析发现，二者之间呈显著或极显著相关。综合来看，秸秆还田有利于土壤腐熟化并提高土壤地力，且土壤肥力随还田年限的增加而增加。
关键词：秸秆还田；土壤养分；腐殖质碳；酶活性
中图分类号：S141.9；S154.3 文献标識码：A 文章编号：0439-8114（2017）19-3640-06
DOI：10.14088/j.cnki.issn0439-8114.2017.19.012
Abstract： The variation of humus compositions，enzyme activity and nutrient content under the treatments of CK （without application of straw），SRF1（straw returned one year） and SRF2（straw returned two years） was studied through two-year field location experiment in the vineyards，aimed to clear the impact of straw on soil humus carbon component and soil enzyme activities. The results showed that，compared to CK，soil humus carbon increased by 25.8% and 31.6% respectively under SRF1 and SRF2，and these two treatments significantly improved the soil of PQ （the ratio of humic acid carbon and humus carbon） and HAC/FAC（the ratio of humic acid carbon and fulvic acid carbon）. Straw significantly increased soil enzyme activities，compared to CK，soil urease activity under SRF1 and SRF2 increased by 42.4% and 60.6% respectively，acid phosphatase activity increased by 9.2% and 10.5% respectively，and invertase activity increased by 28.1% and 30.6% respectively. Compared with CK，soil pH under SRF1 and SRF2 increased from 5.86 to 6.48 and 6.79 respectively. The soil organic mater，alkali-hydrolyzable nitrogen， available phosphorus，rapidly available potassium， available zinc，available boron and available iron after straw returned significantly increased compared with CK， and increased with the extension of straw returned years. Through the soil humus carbon fractions and soil enzyme activities correlation analysis found that， different soil activity and soil humus carbon fractions were significantly associated. In terms of total up， straw returned was beneficial to soil putrescicity and improve soil fertility，and the soil fertility increased with the extension of straw returned years.
Key words： straw returned； soil nutrients； humus carbon； enzyme activity
秸秆是农作物收获后的残留物，同时也是物质及养分的载体，属可再生生物资源[1]。农作物秸秆中不仅含有丰富的碳源，还可提供除N、P、K养分之外的中微量元素及大分子有机化合物养分，因此，秸秆也是农业生产中一种重要的有机肥源[2]。中国秸秆资源量丰富，年产达7亿～8亿t，但利用率却不足50%，有超过30%的秸秆被丢弃或者焚烧[3，4]，这不仅造成资源浪费，还使得土壤表层有机碳下降，养分损失，并且焚烧会使大气环境恶化，进而影响人类健康[5，6]。将其还田利用不仅可以合理处理大量剩余秸秆，还可提高土壤肥力、养分和有机碳含量，改良土壤结构和物理性状[4，7-9]。秸秆利用一直是农业生产研究的热点问题，但利用方式不一，所带来的结果也不尽一致。