杉木人工林皆伐对林地径流水化学特征的影响

杉木人工林皆伐前后径流水化学特征研究结果表明，杉木人工林皆伐后引起林地土壤养分大量流失，皆伐后2年内土壤N素、P素、盐基离子（K^ ,Na^ ,Ca^2 ,Mg^2 ）的可溶性盐分的流失增量分别为20.54kg/hm^2、0.817kg/hm^2、42.67kg/hm^2和774.44kg/hm^2，表晨杉木人工林具有一定的调节、富集和保持土壤养分的能力。

The influence of clear cutting Chinese fir plantation on the characteristics of runoff water chemistry of forest land

The influence of clear cutting Chinese fir plantation on the characteristics of runoff water chemistry are studied to explore the capability of Chinese fir plantation of regulating, accumulating and conserving soil nutrients. Periodically sampled runoff from the ditch below the catchment area before and after clear cutting and analysed nutrient quantities of runoff sampled, the differences between nutrient quantities of runoff before clear cutting and those after clear cutting are the increments of forest land nutrient loss caused by clear cutting Chinese fir plantation. Experiments continued for 5 years,the results show that the clear cutting Chinese fir plantation results in soil nutrients running off in great quantity. In two years after clear cutting, the running off increments of N,P,base cation (K⁺,Na⁺,Ca²⁺,Mg²⁺) and dissolvable salts are 0.54kg/hm²,0.817kg/hm²,42.67kg/hm²,774.44kg/hm² separately. The results indicate that Chinese fir plantation has a fair capability of regulating, accumulating and conserving soil nutrients.