带状采伐对毛竹林土壤理化性质和酶活性的影响

Effects of strip clear cutting in Phyllostachys edulis forests on soil physical and chemical properties and enzyme activities

为研究带状采伐后土壤质量的恢复特征,以福建省建瓯市房道镇千竹园毛竹林为研究对象,设置两种不同采伐宽度的带状采伐,即5 m(C1)和7 m(C2),以不进行采伐处理为对照(CK),研究采伐后Ⅰ时期(2018年10月)和Ⅱ时期(2019年6月)土壤理化性质及土壤酶活性的变化特征。结果表明:采伐后Ⅰ时期和Ⅱ时期相比,土壤质量含水量、最大持水量和毛管持水量显著增加;采伐后Ⅰ时期C1和C2的土壤容重小于CK,但采伐后Ⅱ时期则相反。土壤中的水解氮(DON)含量在采伐后Ⅰ时期表现为C2>C1>CK,在采伐后Ⅱ时期不同土层平均值表现为CK>C2>C1;土壤中的有效磷(AP)含量在采伐后Ⅰ和Ⅱ时期均表现为C1>C2>CK;土壤中的速效钾(AK)含量、电导率(EC)和p H值在采伐后Ⅰ和Ⅱ时期均表现为C2>C1>CK;与采伐后Ⅰ时期相比,采伐后Ⅱ时期的土壤蔗糖酶(S-SC)与土壤酸性磷酸酶(S-ACP)活性升高,而土壤脲酶(S-UE)活性下降。带状采伐能明显增加土壤中AP和AK含量,提高EC、土壤p H值和S-UE活性;7 m带状采伐在改善土壤理化方面优于5 m带状采伐;故通过带状采伐可以提高土壤质量,有利于毛竹林恢复地力。

To study the characteristics of soil quality restoration after strip clear cutting,taking the Phyllostachys edulis forest in Jian’ou City,Fujian Province as the research object,two clear cutting strips with widths of 5 m(C1)and 7 m(C2),and a control(CK)with no cutting were set.This was done to study the changes in the soil physical and chemical properties and enzyme activity during periodsⅠ(October-2018)andⅡ(June-2019)after strip cutting.The results showed that:the normal P.edulis forest had a significantly higher soil mass water content,maximum water-holding capacity,and capillary water-holding capacity compared to P.edulis forest during periodsⅠandⅡ.Additionally,the soil bulk densities of C1 and C2 were smaller than that of CK,but the performance was reversed during periodⅡ.The content of soil hydrolyzed nitrogen(DON)was in the order of C2>C1>CK during periodⅠ,while the average values of different soil layers were in the order of CK>C2>C1 during periodsⅠandⅡ.The content of soil available phosphorus(AP)showed an order of C1>C2>CK during periodsⅠandⅡ.The content of soil availablepotassium(AK)and electrical conductivity(EC)in the soil showed an order of C2>C1>CK during periodsⅠandⅡ.Compared with periodⅠ,the soil invertase(S-SC)and soil acid phosphatase(S-ACP)activities increased,while the urease(S-UE)activity decreased during periodⅡ.Strip clear cutting can significantly increase the activities of AP,AK,EC,p H,and S-UE.Meanwhile,7 m strip cutting is more effective than 5 m harvesting concerning the soil physical and chemical properties.Therefore,strip clear cutting can improve soil quality and the restoration of P.edulis forests.