摘要
经研究林地凋落物的重量分布特征,发现其总体分布具有偏态分布的特点。在中间区段(约为湿重+1.5S),凋落物重量在林地具有均匀分布的若干性质。测定林地凋落物累积量时,在27°山坡上,当样方面积超过0.5m^2后,所需样方数目渐趋稳定。因此建议设置样方时面积以为0.5—1.0m^2为佳。本文还计算出样方面积不同时,为保证一定精度所需的最少样方数。只要能够达到这一数目,任何大小的样方都能满足精度的需要。最后,通过研究坡度对凋落物收集的影响,可以看出,随坡度增大,林地凋落物重量的变异程度增加,同一取样面积上需设置的最小样方数目也随之增加。
This study is carried out in secondary forest of Betula plctyphylla.Ey analyzing the distribution featines of litter amovnt on forest fleer . it is discovered that there are some characteristics of non-normal distribution , in the intervals (about green weight X ±1.5Sx-) there are some features of uniform distribution for litter amount ,on forest floor. While estanrating litter amount , the required minmum quadrate number is almost the same as quadrate size exceeds 0.5m2 on a 27° hillside. Therefore, it is recommended that the optimum quadrate size is 0.5-1.0m2. The required minimum quadrate number is also calculated for guaranteeing demanding precision when different quadrate size is chciced. Any size of quadrate can satisfy the demanding precision only can the minimum number be enough. At last, the effects of slope on litter amount gathering are determined, it is well shown that, the variability of litter r.mount on forest floor grows larger with the slope, consequently, the minimum quadrate number is needed more on the steeper slope of hillside.
出处
《生态学报》
CAS
CSCD
北大核心
1989年第1期59-65,共7页
Acta Ecologica Sinica
关键词
次生林
凋落物
样方
precision estimating litter amount,quacdtrate size number, determine
