论文部分内容阅读
通过处理 (根据当地习惯收割凋落物和林下层 )和保护 (无任何人为干扰 )样地的比较试验 ,1990～ 1995年期间研究了人为干扰对鼎湖山生物圈保护区马尾松 (Pinus massoniana)林土壤细根和有机质的影响。在此 5 a的研究期间 ,由于人为干扰活动而直接从处理样地取走的林下层和凋落物总量为 2 1.7t/ hm2。在保护样地 ,林下层生物量从 2 .2 t/ hm2增加至 11.10 t/ hm2 ,地表凋落物 (包括枯死的林下层 )量则从 3.0 t/ hm2 增加至 13.3t/ hm2 。收割林下层和凋落物这种人为干扰活动对林地土壤细根生物量的影响不明显 ,但却显著降低土壤轻腐殖质 (Soil lightorganic matter)量。在细根分解过程中 ,其分解速率在处理样地(试验结束时细根残存量占起始量的 4 0 .8% )显著高于在保护样地 (试验结束时细根残存量占起始量的 4 4 .3% ) ;与 Ca、Mg和K元素不同 ,N和 P两种元素的释放速率在处理样地显著高于保护样地 ,表明这种人为干扰活动不仅直接取走所收割的林下层和凋落物中的养分 ,而且还可能增加林地有效养分的流失潜力
From 1990 to 1995, human disturbance was studied through comparison experiments on plots of litter and shelterbelts (according to local habits) and protection (without any human disturbance). Soil samples from Pinus massoniana forest in Dinghushan Biosphere Reserve Fine root and organic matter effects. During the 5-year study period, the total amount of understory and litter removed directly from the treated plots due to human disturbance activities was 2 1.7 t / hm2. In the protected plots, the biomass of the lower layer increased from 2.2 t / hm2 to 11.10 t / hm2, and the litter (including the dead forest layer) increased from 3.0 t / hm2 to 13.3 t / hm2. The man-made disturbances of understorey and litter in the harvested forests did not significantly affect the fine root biomass of forest soils, but significantly decreased the amount of soil light organic matter. In the process of fine root decomposition, the rate of decomposition was significantly higher in the treated plot (40.8% of the initial amount at the end of the experiment) than in the protected plot (the fine root remnants accounted for Different from Ca, Mg and K elements, the release rates of N and P were significantly higher in the treatment plots than those in the protected plots, indicating that this anthropogenic interference activity not only directly removed Harvested understory and litter nutrients but may also increase the potential loss of available nutrients in the woodlands