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川滇高山栎是青藏高原具有代表性的常绿阔叶树种,在藏东南林区大面积连续分布,对高山峡谷地带的水土保持和水源涵养具有重要的防护作用和较大的生态效益.采用聚集度指标、以空间推时间法的Logistic方程和种群调节的乘幂函数拟合分别对西藏色季拉山川滇高山栎种群的空间分布格局、增长与调节规律进行了研究.结果表明,川滇高山栎幼苗多呈聚集分布,随着演替的进展,川滇高山栎种群的聚集强度减小;川滇高山栎种群增长的环境容纳量为15.2085m2hm-2,内禀增长率为0.614;种群最大增长速率出现在胸断面积9.66m2hm-2处,种群在平均胸断面积46.23cm2(均胸径7cm)~198.723cm2(均胸径15.91cm)阶段自疏强度最大.川滇高山栎种群聚集强度随演替过程逐渐减弱,是种群在有限的环境容量中自疏和自我调节特征的明显表现.Logistic方程即反映了生物种群增长速度的变化和环境容量限制的时滞效应这一重要特征,种群调节的幂函数拟合则有效刻画了生物种群在大量繁殖之后,随着个体增大,个体间资源竞争增强,种群内部出现优胜劣汰的自我调节过程.图4表2参32
Quercus glauca is a representative evergreen broad-leaved tree species on the Tibetan Plateau, which is distributed continuously in a large area in the southeastern part of the Tibet Plateau and plays an important role in protecting water and soil conservation and water conservation in the alpine gorge area. The spatial distribution pattern, growth and regulation of Quercus mongolica populations in Sejila Mountain, Tibet Autonomous Region, were studied by Logistic equation of space push time method and power exponential fitting of population adjustment respectively. The results showed that, Quercus acutissima seedlings mostly aggregated, with the succession progress, the aggregation intensity of Quercus acutissima populations decreased; the Quercus mongolica Quercus mongolica population growth environment capacity was 15.2085m2hm-2, intrinsic rate of increase was 0.614; the largest population The growth rate appeared at the area of 9.66m2hm-2 in chest area, and the population had the highest self-sparseness intensity in the stage of average chest area 46.23cm2 (average chest diameter 7cm) to 198.723cm2 (average diameter at breast height 15.91cm) For the process gradually weakened, is a clear manifestation of self-sparse and self-regulating characteristics of population in a limited environmental capacity.Logistic equation that reflects the changes in the population growth rate and environmental capacity limits System is an important feature of lag effect, and the power function fitting of population adjustment effectively depict the self-regulation process of the survival of the fittest as the individual increases, the competition of resources between individuals increases, and the survival of the fittest appears within the population. 4 Table 2 Reference 32