论文部分内容阅读
【目的】研究黄土高原一年一熟春玉米区不同耕作处理对农田土壤酶活性的影响。【方法】以春玉米品种“沈玉17”为供试作物,采取保护性耕作(NT)、传统耕作+秸秆还田(TS)和传统耕作(CT)3种耕作模式栽培。第2年,分别于播种前(04-17)、拔节期(06-03)、抽雄期(07-16)和成熟期(09-15)用土钻取0～20cm土样,测其过氧化氢酶、脲酶、碱性磷酸酶、多酚氧化酶、蔗糖酶和纤维素酶活性,探索不同保护性耕作方式下土壤酶活性的动态变化规律。【结果】NT条件下,土壤过氧化氢酶和碱性磷酸酶活性均呈先上升后下降的变化趋势。TS条件下,土壤多酚氧化酶活性表现为先下降后上升的趋势,但上升时期出现较晚;土壤蔗糖酶活性表现为先上升后下降的变化趋势,在抽雄期最高;土壤纤维素酶活性在拔节期显著高于NT和CT耕作模式。3种耕作模式下,土壤脲酶活性均呈先升高后下降的趋势。可能由于受土壤水热状况和通气等因素影响,不同处理条件下不同土壤酶活性最高值出现的时期不同。【结论】保护性耕作有提高土壤酶活性的趋势。
【Objective】 The objective of this study was to investigate the effects of different tillage treatments on soil enzyme activities in spring maize fields in a year in the Loess Plateau. 【Method】 The spring maize cultivar “Shenyu 17” was used as the test crop and cultivated in three tillage modes: conservation tillage (NT), traditional tillage + straw returning (TS) and traditional tillage (CT). In the second year, 0-20 cm soil samples were drilled with soil before sowing (04-17), jointing (06-03), tasseling (07-16) and maturity (09-15) The activities of soil enzymes, urease, alkaline phosphatase, polyphenol oxidase, invertase and cellulase were tested to explore the dynamic changes of soil enzyme activities under different tillage systems. 【Result】 Under NT conditions, the activities of soil catalase and alkaline phosphatase increased first and then decreased. Under TS conditions, soil polyphenol oxidase activity showed the trend of first decreasing and then increasing, but appeared later in the rising period; the activity of soil invertase first increased and then decreased, the highest in tasseling stage; the activity of soil cellulase At jointing stage was significantly higher than NT and CT farming patterns. Under the three tillage modes, soil urease activity increased first and then decreased. May be due to soil moisture and heat conditions and ventilation and other factors, different treatments under different soil enzyme activity of the highest value of the emergence of different periods. 【Conclusion】 Conservation tillage tends to increase soil enzyme activity.