tree line

Review on the ecological relationships between forest trees and ectomycorrhizal fungi;

外生菌根菌与森林树木的相互关系

The altitude of the forest line that is generally marked by the upper limit of the dark coniferous forest zone in the vertical zones of natural vegetation is controlled by the temperatures and their annual range.

在自然植被垂直带谱上一般以暗针叶林带的上限代表森林线,它的海拔高度取决于温度及其年较差。

Given integers k, s, t with 0≤s≤t and k≥0, a (k,t,s) -linear forest F is a graph that is vertex disjoint union of t paths with a total of k edges and with s of the paths being single vertices.

设k,s,t为满足s≤t的非负整数,F是由t条点不交的路构成的边数为k的森林,如果F中恰有s条路是单点,则称F为(k,t,s)-线性森林。