Answer and Explanation:
- the upper boundary of sub alpine ecosystem is known as tree line and lower boundary of sub alpine ecosystem is known is montane zone
- the tree line is the edge of habitat at which trees are capable of growing it is found at very high elevation beyond this there is no life of trees
- the upper montane zone is vegetarian type generally found above the mixed coniferous forest and bellow the sub alpine forest
HOW DOES IT VARIES ACROSS THE STATE :
- the marginal conditions make the sub alpine ecosystem sensitive to environment change
- the long lived nature of the sub alpine species make the zone a good study system