Nutrient Characteristics of Soil Aggregates in Larix gmelinii Plantations of Different Forest Ages from Seriously Burned Area in Great Khingan Mountains
[Objective]In order to know the changes of nutrient content and distribution of soil aggregates under Larix gmelinii plantation of different forest ages after vegetation restoration in severely burned areas of Greater Khingan Mountains.[Methods]Takes the Larix gmelinii plantation(11,21 and 32 years)planted in 1989,2000 and 2010 on the severely burned areas formed by the severe forest fire in Greater Khingan Mountains in 1987 as the research object.By measuring the contents of organic carbon,total nitrogen,total phosphorus,alkali-hydrolyzed nitrogen,available phosphorus and available potassium in soil aggregates,the nutrient distribution characteristics of soil aggregates were studied.[Results](1)The contents of organic carbon,total nitrogen,total phosphorus,alkali-hydrolyzed nitrogen and available potassium in soil aggregates of different particle sizes increased gradually with the decrease of particle size,and the content of＜0.5 mm particle size was the largest.(2)As the age of forest increased,the content of organic carbon,total nitrogen,total phosphorus,alkali hydrolyzed nitrogen and available phosphorus in soil aggregates gradually increased.The nutrient content of soil aggregates in 32 years Larix gmelinii plantation was significantly higher than that in 11 years Larix gmelinii plantation.The contents of organic carbon,total nitrogen,total phosphorus,alkali-hydrolyzed nitrogen and available phosphorus in soil aggregates were significantly increased by 77.35％～130.24％,77.61％～143.36％,105.84％～147.98％,94.58％～155.96％and 206.98％～537.09％,respectively,compared with 11 years Larix gmelinii plantation(p＜0.05).The organic carbon content of soil aggregates at different particle sizes in 21 years was higher than that in 11 years Larix gmelinii plantation,but there was no significant difference.(3)There was a strong correlation between organic carbon and total nitrogen and alkali-hydrolyzed nitrogen in soil aggregates(p＜0.01).Soil organic carbon and alkali-hydrolyzed nitrogen content had the strongest correlation with＜0.25 mm fraction content.Total nitrogen,total phosphorus,available phosphorus and available potassium had the strongest correlation with＞0.25 mm fraction content(p＜0.01).[Conclusion]The nutrient of soil aggregates in Larix gmelinii plantation showed surface aggregation.The nutrient content of soil aggregates in Larix gmelinii plantations planted on severely burned areas in Greater Khingan Mountains increased with the increase of forest age.The Larix gmelinii plantation planted for 32 years significantly increased the nutrient content of soil aggregates.The results provide a scientific basis for the restoration of artificial vegetation in the severely burned area of Greater Khingan Mountains.
万方数据
维普
