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对辽宁省章古台地区的几种主要针叶树种的针叶养分及其林分表层(0-15cm)土壤养分进行研究。结果表明,不同年龄樟子松(45、29和20年)(Pinussylvestrisvar.mongolica)林地表层土壤养分并无显著差别,而29年樟子松林分表层土壤全N、全P和N:P比显著高于相近年龄的赤松(P.densiflora)(29年)和油松林(P.tabulaeformis)(31年)。随着樟子松年龄的增加,叶片P含量逐渐减少,而叶片N和K含量则未表现出随年龄而变化的趋势;对于年龄相近的三个树种,叶片N和P含量表现为:樟子松>赤松>油松,而叶片K含量在三个树种中并无显著差别。表层土壤的全N和全P,有机质和全P以及叶片N和P含量之间表现出了显著的相关性,但是,林分表层土壤养分和树木针叶养分之间并无显著相关关系,这可能与当地对凋落物的过度收集,过度放牧以及土壤水分含量低有关。最后,根据国外研究结果引入N:P比阈值来分析研究区域的N,P养分状况,基于章古台地区这几种针叶树种针叶N:P比,我们认为研究区域的樟子松随着年龄的增加受N限制的可能性降低,29年的赤松林整体表现出不受N和P养分限制,而31年的油松林则表现为系统N和P都供应不足。图3表3参45。
The coniferous nutrient of several major coniferous species in Zhanggutai area of Liaoning Province and its soil nutrients in the surface layer (0-15cm) were studied. The results showed that there was no significant difference in the surface soil nutrients of Pinus sylvestris var. Mongolica at different ages. However, the N, P and N: P ratios of Pinus sylvestris var. Mongolica forest in 29 years were significantly P.densiflora (29 years) and P. tabulaeformis (31 years) above similar ages. With the increase of Pinus sylvestris var. Mongolica, the content of P in leaves decreased gradually, while the content of N and K in leaves did not change with age. For the three tree species with similar ages, the N and P contents in leaves were: Pinus tabulaeformis> Pinus tabulaeformis> Pinus tabulaeformis, but leaf K content did not differ significantly among the three tree species. There was a significant correlation between total N, total P, organic matter, total P, and leaf N and P content in surface soils, but there was no significant correlation between surface soil nutrient content and tree needles nutrient content It may be related to the local over-collection of litter, overgrazing and low soil moisture content. Finally, based on the results of foreign studies, we introduced the N: P ratio threshold to analyze the status of N and P nutrients in the study area. Based on the N / P ratios of needles in these coniferous species in the Zhanggutai area, we found that the Pinus sylvestris var. The increase in age is less likely to be restricted by N, and the 29-year-old Pinus thunbergii forest appears to be unaffected by N and P nutrients, while the 31-year-old Pinus tabulaeformis appears to be under-supplied by both N and P systems. Figure 3 Table 3 Reference 45.