不同还田方式下白三叶腐解特征及对茶叶产量和品质的影响

Decomposition Characteristics of White Clover under Different Returning Methods and the Effects on Yield and Quality of Tea

为明确不同还田方式下白三叶腐解特征和养分释放规律以及对茶叶产量和品质的影响,寻求绿肥最佳的还田方式,为白三叶在茶园的合理利用提供技术依据。采用尼龙网袋法,在茶园模拟白三叶在翻压(T1)、割覆(T2)和自然枯死(T3)3种还田方式下的腐解特征和氮、磷、钾、碳等养分释放规律,并同时进行小区试验分析茶园间作白三叶3种不同还田方式对茶叶产量和品质的影响。结果表明,茶园间作白三叶3种还田方式下在160 d后的累积腐解率为73.4%~89.8%,快慢表现为T1>T2>T3,其中T1和T2处理呈现先快后慢的特点,T1处理:0~10 d为快速期,10~160 d为缓慢期,T2处理:0~20 d为快速期,20~160 d为缓慢期,而T3处理腐解时间滞后,从第40天开始腐解,后期保持较快的腐解速率;养分释放率和释放量表现为T1>T2、T3,氮、磷、钾、碳4种养分释放都较彻底,其中钾释放最彻底,氮、磷次之,碳最少,在160 d后钾、氮、磷、碳的累积释放率分别为95.1%~99.7%,75.3%~95.6%,86.4%~93.9%,69.5%~91.6%;白三叶还田后能提高夏秋茶产量,夏茶和秋茶分别比CK提高了9.4%~27.0%,5.9%~28.2%,改善茶叶品质,提高夏秋茶水浸出物和氨基酸含量,分别高出CK 0.7%~4.2%,2.0%~17.0%,降低夏茶酚氨比,降幅为0.9%~12.0%。因此,综合考虑腐解速率、养分释放量以及对茶叶产量和品质等因素,茶园间作白三叶还田方式优先推荐翻压还田(T1处理)。

To provide technical basis for the rational utilization of white clover in tea plantation and seek the best return method,the decomposition characteristics of white clover under different returning methods and the effects on the yield and quality of tea were studied.Using nylon mesh bags,the decomposition characteristics and nutrients releasing law of white clover under soil coverage treatment(T1),straw mulching treatment(T2)and natural death treatment(T3)were researched,and it was set plot experiment in tea plantation to analyse the affects of tea yield and quality.The results showed that:the cumulative decomposition rate was 73.4%-89.8%after 160 days under the three returning methods of tea plantation intercropping white clover,and the speed was T1>T2>T3.T1 and T2 showed the characteristics of fast first and then slow.T1 treatment was the fast stage from 0 to 10 days,and the slow stage from 10 to 160 days.T2 treatment was the fast stage from 0 to 20 days,and the slow stage from 20 to 160 days,however,the decomposition time of T3 treatment was delayed,and the decomposition was started from the 40th day,and kept fast in the later period;the release rate and amount of nutrients showed as T1>T2 and T3,nutrients releasing of N,P,K,C were more complete.The releasing of K was the most complete,followed by N and P,the C was the least.After 160 days,the releasing rates of K,N,P and C were 95.1%-99.7%,75.3%-95.6%,86.4%-93.9%and 69.5%-91.6%;the yields of summer and autumn tea were increased by 9.4%-27.0%and 5.9%-28.2%than CK,and the tea quality was improved.The water extract and amino acid of summer and autumn tea were increased by 0.7%-4.2%and 2.0%-17.0%,and the phenol/ammonia of summer tea was decreased,the decreasing rate was from 0.9%to 12.0%.Therefore,considering the factors of decomposition rate,nutrient releasing,yield and quality of tea,the returning method of soil coverage(T1 treatment)is fist recommended udder tea plantation intercropping white clover in tea plantation.