The eastern part of Liaoning Province lies east of Tieling-Yingkou line. Its north is a mountainous area, belonging to the Changbai flora region. Its south is a hilly land of the Liaotung peninsula, belonging to the Huabei flora region and having some cold resistant subtropical plants. Mixed broadleaf deciduous and needleleaf forests, Pinus tabulaeformis and P. densiflora forest and deciduous broadleaf forests are zonal vegetations of the eastern part of Liaoning Province. However, the secondary Quercus mongolica forests and various shrubs are distributed widely. The eastern part of Liaoning Province may be divided into the following two vegetation zones: 1) The north is a temperate zone of the mixed needleleaf and broadleaf deciduous forest; 2) The south is a warm temperate zone of the broadleaf deciduous forest where the southeast of Xiong-yue-Qingyishan line is Pinus densiflora oak forest subzone and the north-west is Pinus tabulaeformis oak forest subzone.

This paper deals with the phytosociological characters of the Wumon-fir (Abies georgei var. smithii) forest, which has been remained in the Wumon mountain range of Yunnan. Only a small area of this forest is now disperse over there, located 3100--3900m. in altitude. It is the only subalpine coniferous forest found in the north part of the middle Yunnan Plateau, and is considered as an important component of the vertical vegetation spectrum in that region. The natural community is a uni-dominant forest, dominated by the Wumon-fir. In this forest, a few Tsuga dumosa is found occasionally. Some species of Sorbus, Viburnum, Salix, Acanthopanax, Hydrangea, Ilex, Rhododendron and others are seen in the understory. The shrub layer is mainly consisted of the subalpine bamboo Sinarundinaria, and there are many species in herb layer. The great majority of the floristic component belongs to Sino-himalayan. The phytosociological characters of this fir forest are very similar to the north-west one of Yunnan, but the tree layer lacks species of Picea and Larix. Therefore it may be stated that this forest is a south-east boundary type of the vegetation in the area among the north-west Yunnan, the south-west Sichuan and the south-east Tibet. It has arrived at the distributional limitation of that area. This forest is the remainder of the natural history, and under the men’s activities, its area has been become narrow and narrow. Based on this reason, it should be protected strictly. If so, it will bring in very active role about great changes of agriculture, forestry, pasturage in the Wumon mountain range.

This study aiming at a contrasted observation with forest land and burnt land was carried out in the tropical semideciduous monsoon forest on the lower mountain of the western slop of the Jian Feng Ling mountain in Hainan Island. The area of the plot to observe the surface run-off is 100m2. The ecological consequence caused by "slash- and burn- cultivation" was investigated in the same year. After slash-and burn- cultivation of the forest :the microclimate became dry and hot rapidly and the relative humidity was decreased about 10--20%. The air temperature was increased 1.5-3℃, while the soil and the soil temperature was increased 8℃. The defoliation period of the forest trees was not obvious. As compared with the forest maintained, the mean run-off increased 5-6 times and the run-off coefficient was 4-5 times more. The soil lost was 105m3 per ha. and the amount was 7 times more than that on the forest land. The suspending silt was reaches to 362kg. the amount of which was 20 times more than those on the forest land. About 2cm topsoil was lost. The nutrients lost with the loss of water and soil. They include 19,800kg. of organic matters and 1,000kg. of total nitrogen, l60kg. of available potassium, l6kg. of available phosphorus and 2000kg. of exchangeable base. However, the soil acidity is not increased significantly. The tropical forest ecosystem plays a great role in environmental protection. The “slash-and burn-cultivation” is very destructive. Therefore, this way of land-use should be abolished.

This paper briefly explains the principle and method in compiling the vegetation map of Guangxi with the scale of 1:2500000. Here the legend is described as well. At present, areas occupied by the main zonal vegetation type in Guangxi are too small to present on this map. In order to represent them completely, the following ways are adopted. If the same vegetation units are congregate, these areas may be portrayed as pattern by enlargement——combining them together. Otherwise, the separate areas can be indicated by symbols which are still given their normal position in the legend for keeping the later systematic.On the basis of phytocoenological characters, the legend is arranged in three classes, rarely in four. The physiognomy features of vegetation are considered in the first class; the life form of the dominant compositions of phytocoenosis, in the second class; the dominant and characteristic species, in the third; the dominant species in the scrub layer in the fourth. Only the later two classes are revealed on the map. As far as the vegetation classification is concerned, they correspond to the formation or formation combination and association group separately. The cultural vegetation is classified based on the cropping system. Some sorts of the timber forests and economic forests appear frequently and always occupy small areas, so it is impossible to show all of them on the map. In this case symbols have been used to be placed on their principal producing areas. Some relic or significant forests are also expressed by symbols which are included in the supplementary legend. With 44 items in the legend and 7 in supplementary legend, the map shows briefly the main regularity of geographical distribution of vegetation in Guangxi. It may be used as a reference for compilation of very small scale map of regionalization of agriculture, forestry and pasturage.

The geographical or ecological laws of vegetation are determined mainly by the component factors of temperature expressed by the latitudinal zonation and of moisture expressed by the longitudinal zonation. Thus, these laws are fundamental principles of vegetation regionalization of China. The zonal vegetational types, groups of indicator plants, cropping systems, species or even races of cultural plants and their growth conditions should be considered as the criteria of regionalization. China stands on the west coast of the Pacific Ocean. The summer monsoons coming from the south-east play a great role in dominating the climate of the coastal areas which are humid forest regions. Atmospheric moisture becomes less and less as one goes to westwards. The north-western parts of the country, the arid desert regions, are very shortage of rainfall. The lands lying between the two areas mentioned above are semi-arid grassland regions. As regards the east and south-east parts of the country, the different forest regions correspond respectively to the latitudinal zonation varying from the north to the south, namely, the cold-temperate deciduous needleleaf forest, the temperate deciduous broadleaf forest, the subtropical evergreen broadleaf forest and the tropical seasonal rain-forest. Except the cold-temperate region, the rest three forest regions may be respectively divided into two subregions. The semi-arid grasslands are divided into two regions. One is the temperate steppe region including the one subregion occurring in the plain of China’s northeast and the eastern portion of the Inner Mongolian Plateau, and another subregion occurring on the loess Plateau. The high-cold meadow and steppe region is situated on the east-central and southern portion of the Ching-hai-Tibet Plateau with about 4000m. above sea level. The arid desert lands may be also divided into two regions. One is the temperate desert region including the northern subregion and the southern subregion. Another region is high-cold semi-desert and desert region.