Kinds Of Forests Research Articles

北九州の2種の森林の樹冠の植食動物の糞量と摂食量

北九州の2種の森林の樹冠の植食動物の糞量と摂食量

Determination of monoterpene hydrocarbons in the atmosphere

A gas chromatographic—mass spectrometric technique for the analysis of trace concentrations (sub-ppb*) of monoterpenes in the air is descrbed. Samples wre collected on Tenax GC adsorbent and thermally desorded onto the analytical column for separation and detection by selected ion monitoring. Experimental results are given for different kinds of forests in the Tsukuba district of Japan. The diurnal variation of the monoterpene concentration in the atmosphere was also measured in a pine forest.

Change in African Vegetation

A common element in all African studies is the background of the African environment. My first real sight of Africa, thirty years ago, was in the long train journey from Lagos to Zaria. As a botanist, I was fascinated then by the changing patterns of vegetation — different kinds of forest and savanna, a rich diversity of plant species. I suppose all members of our Association have seen something of Africa's vegetation and, especially on long journeys, may have thought it monotonous and dull. However, as with all forms of scholarly inquiry, what at first sight seems uniform becomes, on close inspection, a puzzling jumble, and only after a fair amount of study do meaningful patterns and causal relationships emerge. My interest was aroused by that very obvious part of the African environment and over the years I found that my vegetational studies were often relevant to researchers in quite different disciplines.

The Chages in the Cryptomeria Forests in Akita

So-called Akita-Sugi, the Cryptomeria of Akita district, has a high reputation all over the country with its lumber of high quality. Among the merits of the lumber, are counted particularly the huge size of the trees and the beauty of the grains. Excellent cryptomeria forests mostly belong to the national forests in northern Akita Prefecture. But recently natural Akita-Sugi forests are remarkably decreased and are replaced by other kinds of forests. Two figures show this change from natural forests to afforestation.

自然公園における森林の風致的取り扱いについて

In recently according to increase of demand for sightseeing, the number of visitors to the natural parks are increasing year after year.In natural park the forest is a important factor in landscape.At the Chubu-sangaku national park we investigated the forest constitution and what kind of forest are better from the view-point of landscape.In this area, forestation and cut down a forest are not take and the forest put in natural state, so stand growing to over-thick and beauty effect of forest is not bring out.Crown density of forest in this area is more than 50% in general and some time over 100%.Result of this investigation the worthy forest from the view-point of landscape is as follows.(1) The crown density of 28-47% is better as a forest constitution in national parks.(2) In light demanding tree like the white birch and the black alder the crown density is better under 30% in young stand, and 40-50% in old growth stand.(3) In case of the old age of katsura-trees and the elm-tree, although the crown density are 60% or more than that, the forest show light and magnificent apearance as a result of highness of trees.