I-107杨树连作对土壤有机碳和全氮的影响

Effect of Continuous Cropping of I-107 Poplar Plantation on Soil Organic Carton and Total Nitrogen

为探讨杨树人工林连作对土壤碳氮养分的影响,以大汶河流域I-107杨树人工林为研究对象,系统地研究连作对I-107杨树人工林有机碳密度(SOCD)和土壤全氮密度(STND)以及分布特征的影响。结果表明:不同杨树人工林样地SOCD差异明显,表现为一代林>二代林>荒地>三代林,其中一代林林地SOCD分别比二代林、荒地和三代林高20.59%,23.79%和48.05%;STND呈显著性差异性,表现为一代林最高,其次为荒地、二代林,三代林密度最低,与其他林地STND相比一代林分别高25.27%,41.28%和7.54%;各林地土壤C/N具有显著性差异,SOC与STN含量回归相关分析亦显示出SOC和STN具有显著的回归相关性。综上,随着I-107杨树人工林连作代数的增加,SOCD和STND均逐渐降低,因此I-107杨树人工林的经营活动中要尽量避免连续多代经营。

In order to study the effect of continuous cropping of poplar plantation on soil organic carton（SOC）and soil total nitrogen（STN）,the effect of continuous cropping of I-107 poplar plantation on the change of soil organic canton density（SOCD）and soil total nitrogen density（STND）and its distribution was studied in the Dawenhe basin.The results showed that the SOCD had a significant difference in different I-107 poplar plantation.The order of SOCD was the first generation plantation,the second generation plantation,the wasteland and the third generation plantation.The stock of SOC of the first generation plantation increased by 20.59%,23.37% and 48.05%compared with the second generation plantation,the wasteland and the third generation plantation.The STND had a significant difference in different poplar plantation.The order was the first generation plantation,the wasteland,the second generation plantation and the third generation plantation and the stock of STN of the first generation plantation increased by 25.27%,41.28%and 7.54%compared with the wasteland,the second generation plantation and the third generation plantation.The ratio of C and N had an obvious difference among the wasteland,the first generation plantation the second generation plantation and the third generation plantation.And by using regression analysis,it found the SOC content had a significant linear relationship with the content of STN in the wasteland,the first generation plantation,the second generation plantation and the third generation plantation.In conclusion,with the increase of generation,the SOCD and STND decreased gradually.Therefore,poplar plantation management should be avoiding continuous generation and take a rotation or replace tree species to avoid multiple generation effect caused by continuous cropping.During the course of forest management,the scientific managements and logical fertilizer applications were very important to poplar plantation especially the second generation plantation and the third generation plantation.Also,they could improve the fertility of the forest soil and the stability of the poplar plantation.