The caloric values (containing ash)of main plant species in a tropical mountain rain forest at Jianfengling, Hainan Island of China were measured by sampling 67 tree species, 10 shrubs and 6 lianas. The results indicated that the caloric values for tree species were generally higher, and the values of the leaf, stem, branch, bark, root and the plank-buttress were 20470.2, 19523.2, 19401.2 19325.0, 19250.4 and 19454.5J/g respectively according to average values of 67 tree species. Caloric values for shrubs were lower than trees’, the values for the leaf, shoot and root being only 18566.4, 18730.1 and 18530.4J/g respectively. Woody lianas had higher caloric values than herbal lianas. There were significant difference in caloric values among different species. Generally speaking, the megaphanerophyte plants had higher caloric values than nanophanerophyte plants. It is clear that the values were related to the plant life-form. Different individuals of the same species were not obviously different in caloric values. It was initially proved that some tropical plants contained certain amounts of elements such as Si, Fe, Mn, Mg, Cu, Ca, and Zn. indicating that tropical plants possessed a particular bio-geochemical cycling pattern. These elements could form oxides after plants being burned, therefore, this problem should be further studied in the future.

In this paper, the distribution of NPP of natural vegetation in China was given according to a new NPP model. This NPP model was based on ecophysiological feature and regional evaportranspiration model relating the two well known balance equations on the earth’s surface, water balance equation and heat balance equation. The changing pattern of NPP in China was also given under doubled CO2 concentration. This study would help to make good use of natural resources and to make scientific count-measures under global climate change.

The accumulation and dynamic of heavy metal, Cu, Pb, Zn, Cd and Cr elements were studied in Rhizophora stylosa mangrove community at Yingluo Bay of Guangxi, China. The results showed that: 1) In different parts of the plant the contents of the elements were. Cu 0.433～1.21, Pb 0.369～1.88, Zn 2.84～7.66, Cd 0.020～0.233 and Cr 0.330～0.562(μg/g). The contents of the elements in residues were much higher than those in the plant and litter fall.2)The pool amounts of the elements in standing crop of the community were. Cu 28.73, Pb 25.25, Zn 143.68, Cd 3.14 and Cr 14.61(mg/m2). The pool amounts of the elements in residues were: Cu271.68, Pb 323.41, Zn 1983.70, Cd 8.18 and Cr 34.44(g/m2). 3) The biological cycles of the elements in the community were: Annual retention, Cu 1351.70, Pb 1613.12, Zn 8808.37, Cd 240.74 and Cr 759.30 (g/m2); Annual retention: Cu 843.46, Pb 806.921, Zn 4694.10, Cd 94.88 and Cr 464.80 (g/m2); Annual return Cu. 509.24, Pb 806.21, Zn 4114.27, Cd 145.86 and Cr 294.50 (g/m2). 4) the turnover period was: Cu 56, Pb 31, Zn 35, Cd 22 and Cr 50 (a) . The flow coefficients were Cd>Pb and Zn>Cu and Cr.

There were rich seeds of Larix gmelini dispersing naturally in the soil of old-growth larch stands after a mast year. Vital seeds in the soil amounted to 190～320 grains/m2, showing a significant difference among different forest types. Seeds existing in the upper layer of the soil within a scale of 2～4cm accounted for 70%～80% of the total amount. The vitality for most seeds that could germinate rapidly under optimal conditions would last no more than one year, seldom over two years. It was quite evident that the seed bank of Larix gmelini in the soil was of the interrupted type. Meanwhile, by a test of sowing seeds artificially, we got a result the same as above. The pathogens in the soil was the main reason causing death to seeds.

Severe effects of human activities and the rapid growth of population on the environment result in the global change or the regional change, finally affecting the biological diversity at different scales. The grassland is a fragile ecosystem. Under the effects of natural factors and human activities, the grassland is very sensitive to the global or regional climatic changes. The present paper deals with the effects of regional climatic changes in 40 years on plant species diversity in Inner Mongolia. The results are as follows:1, During 40 years (from 1950 to 1990), the moisture was fluctuated due to the grassland regional climate change, and the amplitude and frequency of the fluctuation to the east were all great, especially the fluctuation of 0.3 moisture isohyet.2, In the core-zone of 0.3 moisture isohyet, the relative change rate and fluctuation variance for both the number of individuals and biomass among different sampling plots varied west-east to the adjacent area significantly, There was an increasing trend in species diversity index.3, The moisture isohyet was exactly located at ecotones. In general, the quantitative changes of the vegetation in ecotones were more sensitive than that in the core-zone. The abnormal results in this paper (The core-zone of 0.3 line was more sensitive than the ecotones of 0.13～0.3 and 0.3～0.6) were exactly caused by the effects of regional climatic change.

49 species, including 42 herbs, 3 shrubs and 4 trees, and 33 species, including 29 herbs, 1 shrubs and 3 trees were recorded in the soil seed bank of a deciduous & evergreen broad-leaved mixed forest and in that of a deciduous broad-leaved forest respectively. The seed density for the former forest was 255 grains/m2 and that for the latter one was 145 grains/m2. Little similarity between the species composition of the soil seed bank and the aboveground vegetation species composition for both forests could be found. 33 species and 413 grains/m2 were observed in the gap part of the soil seed bank for the former forest type, and the similarity in species composition between the gap soil seed bank and the non-gap one was only 53.1%.

A nonlinear response function of tree growth to climate variables was developed under the Fritts’ response function, and the cross products of the variables were combined into one item through which it not only avoided the significant loss of degree of freedom but also helped to learn the average cross effect of the climate variables on the growth. A group of cores (15 trees, 30 cores) of Pinus Massoniana which is near its northern distribution limit were dated, and the trends of ring width were deleted, then the obtained chronology and standardized average monthly temperature and monthly precipitation were analyzed by the nonlinear response function. The results showed that the response of the growth was significantly positive to the squares of temperature of December of prior 1 year, March, August and December, and to the squares of precipitation of November of prior 1 year, February, May, August, September and November, but the response was significantly negative to the square of February average temperature. The results could be explained by other′s studies on this species.

The aboveground biomass of Aegiceras corniculatum (L.) Blanco natural forest in Longmen islets of Guangxi was determined in the paper. The aboveground biomass of three natural stands at different ages were investigated with the average standard tree method. According to the data from 18 standard trees of different basal diameter classes, the following regression equations to estimate the biomass of each aboveground organs of A. corniculatum were described from single plant:With significant correlation coefficients, the equations had practical values. The results obtained showed that: (1) The above-ground biomass in 5, 17 and 20-year-old A. corniculatum stands were 743.5g/m2, 7279.0g/m2 and 8817.1 g/m2 respestively. (2) The average productivity were 748.Tg/m2·a,428.2g/m2·a and 440.9g/m2·a respectively.

The introduction experiment for three years showed that the above ground parts of A. fruticosa and R. pseudoacacia were damaged differently coldness in the region (annual average temperature 2.5℃, Jan. average temperature -16.1℃), while the roots could safely survive the winter. The hardiness of roots had increased through three years of natural cold inducement, and LT50 values of them dropped 3.2℃ and 2.0℃ respectively. Meanwhile, the initial damage temperature also dropped 2.0℃ and 2.6℃ The chilling injury experiment demonstrated that roots had phenomenon of tissue softening and browning, accompanied with something of sweet taste. When temperature was below certain points, a Logistic equation could imitate well this chilling injury process.

Based on retention and sorting characters of fossil plants, plants resistance to crushing, fossil assemblage and analysis of the sedimentary environment, the burial type of Early Carboniferous flora form eastern Liaoning was autochthonous burial or hypautochthonous burial, and its living environment was a coastal freshwater swamp environment

The contents and the distribution features of K, Na, Ca, Mg elements in different parts of Alhagi sparsifolia in a saline meadow in the desert region of Xinjiang plain were measured, their interrelations were analyzed. The results showed that these elements had different functions in different organs of the plant. The contents of K and Na in the aboveground part, especially in the leaves, indicated that the species had mechanisms to absorb potassium and Sodium selectively.

Tongtianluo cave is located in the Karst region of Ruyuan county, in the north part of Guangdong province(24°59′N;l13°7′E). It is a huge vertical cave formed by the subsidence of the earth′s surface, with precipitous wall. The diameter of the cave is 73m at its mouth, and 140m at its bottom (along the widest direction). There is no record of exploration to the cave before ours. The evergreen broad-leaved forests were discovered on a areas of 3500m2 at the bottom of the cave, with lots of vines and Pteridophytes. The 12 species of Pteridophytes belonging to 8 genera and 6 families; and 80 species of Angiosperms belonging to 61 genera and 46 families were recorded. The existence and development of these plants indicated that human impact was little in the cave. The characters of the flora in Tongtianluo cave had much to do with the special ecological factors in it, i.e., the low illumination and calcareous clay soil.

Monsoon forest is a vegetation type distributed in tropical regions which has distinct dry and wet seasons. It is more or less leafless during dry season. It is one of the zonal vegetation types in East Asia distributed between tropical forest and savannah forest on the moisture gradient, instead of between tropical forest and subtropical evergreen broad-leaved forest on the temperature gradient. We believe that the monsoon forest could not develop under the climate of Guangdong areas, China. For instance, the Ficus microcarpa + Syzygium odoratum + Sterculia lanceolata formation was not monsoon forest, but tropical seasonal rain forest belonging to tropical rain forest in a wide sense.