Biomass allocation and assimilation efficiency of natural Amour linden (Tilia amurensis) samplings in different light regimes were analyzed in the paper. The results showed that shoot increment of samplings in gap was the highest and that of samplings under canopy was the least. Samplings in gap expressed apical dominance strongly but samplings in full sun and under canopy behaved intensive branching. Lateral competition or moderate shading was favored to bole construction. The patters of biomass allocation of samplings in different light environment were rather similar. The biomass translocated to stem was more than that to other organs, and about one half of photosynthate was used to support leaf turn over. On the contrary, photosynthates of samplings in full sun were mostly consumed in leaves bearing and energy balancing. The carbon assimilation for leaves of samplings in gap was the most efficient, and more carbons were fixed and translocated to non-photosynthetic organs, especially to stemwood.
The forest plant biological diversity investigations were conducted in Laoyeling Forest Ecological Experimental Station on Mao’er Mountains in eastern Heilongjiang Province. Sample plots were six different forest communities. Field works were divided into three seasons: spring, summer and autumn in one year. The results showed that forest plant biological diversity varied with seasons as well as growth forms. Herb species diversity values were the highest in the community growth forms. Diversity indices No,H′ andE 1 were selected out as the best richness, diversity and evenness indices to indicate the biological diversity in forest community.
A brief overview of the system of forest inventory in China and its problems existed is given. Forest planning requires information about the current state of the forest resource. However, generally speaking, the information collected in a periodic inventory may become obsolete already after the first thinning following. Therefore, in order to solve the problem, theory skeleton of thinning inventory technique and its approach in forest inventory, is presented in this paper, with an emphasis on the research and study developing currently thinning inventory.
Seeds and seedlings of five broad-leaved species were separately exposed to simulated acid rain at pH values of 2.0, 3.5, 5.0, and 6.0, or to distilled water (the control). The results showed that seed germination was remarkably inhibited by pH 2.0 treatment for three species. Significant foliar damage, decline in chlorophyll contents, and retardation of the seedlings growth of all the species, were observed at pH 2.0 treatment. The pH 2.0 treatment seemed to be a threshold level for inhibition of seed germination and seedling growth for all the treated species, while seedling was stimulated at pH value between 3.5 and 5.0.
In this paper, the conceptions and developments of ecosystem and ecosystem ecology were reviewed and summarized. Then, the conception, connotation, objective, and development of ecosystem management were expounded. Based on these discussions, forest ecosystem management was discussed. The viewpoint was that the former unreasonable forest resources management should be changed and forest ecosystem management was a suitable way to sustainable development of forestry. The chief research contents were also pointed out in this paper.
Data analysis was made for 54 stands of Chinese pine forests for soil and water conservation and timber. The regression equations were drawn up on forest density and different rafter timber and bush coverage. Based on those equations, the number of rafter timber trees, storage, number of non-rafter timber trees, stand volume and the output value were calculated for six different forest densities ranged from 1250 to 6600 trees/hm2. According to the economic and ecological criteria, the optimum density for Chinese pine forests was determined as 1650 trees/hm2.
Isoperoxidases of fourteen species of poplars in Heilongjiang Province were analyzed by polyacrylamidegel disc-electrophoresis. The major zymogram of petioles of poplars was consisted of twelve kinds of isoenzymes, in which 35% zymogram was just the same and represented the specialized zymograms of poplars. The results of the experiments showed that the closer the affinity relationships of the species were, the greater the similar values between the zymograms were. There were very great similar values among natural hybrid species. But in sect.Tacamahaca Spach, the similar values betweenPopulus koreana Rehder andP. nakaii Skv. were obviously smaller. Isoenzyme analysis provided new information for plant classification on the molecular level.
A new cell line was established from 5-day-old embryonated eggs ofDendrolimus superans and has been designated NEAU-Ds-950821. The cell line consists of mixture of cell types, including majority of spherical shaped cells and a few of spindle shaped cells. The cell line has a population of doubling time of 52.6 h. Chromosome analysis revealed typical lepidopteran chromosomes. Isozyme characterization of Esterase showed the patterns were different from other three cell lines (Ms-927311, Xc-920730, and SF-21AE). Virus infectivity tests revealed the cell line can supportD. superans cytoplasmic polyhedrosis virus.
Fecal indicators of nutritional status of wild ungulates were less constrained than that of blood, rumen contents, or urine analyses. Thus, we compared the nitrogen and fiber concentrations of feces with those of the rumen contents of Mongolian gazelles (Procapra guttrurosa) in Hulunbeier Grassland. Rumen contents and fecal nutritional concentrations varied in different seasons. Dietary nitrogen concentrations only increased linearly with increase nitrogen concentration in fecal in winter. There was a positive correlation between rumen NDF (neutral detergent fiber) and fecal NDF concentrations. But the regression coefficient was small (r=0.3917). There was a significant regression equation between rumen contents ADF (acid detergent fiber) and fecal ADF concentrations, as well as ADL (acid detergent lignin) concentrations. Nitrogen concentration was found to be negatively correlated with NDF, ADF, and ADL concentrations both in rumen and in fecal compositions. Our data suggest that fecal nitrogen, ADF, ADL concentrations may assess winter dietary qualities that are in protein, crude fiber and lignin concentrations for Mongolian gazelles.
The stomach compartments of 51 Mongolian gazelles (Procapra guttrurosa) were weighed and the data were compared with total body weight. The total tissue weights ranged from 2.70% to 2.82% of body weight. Rumens were the heaviest, occupying about 75% of the total stomach, followed by reticulums (9%–11%), abomasums (8%–10%) and omasums (4%–6%). The weights of rumens were directly proportional to body weights and weights of omasums and abomasums were inversely related to body weights. Stomachs of the Mongolian gazelle were of the “mixed feeder” in terms of total weight and contribution of each compartment.
This paper studies the habitat selection of sables (Martes. zibellina) in spring adopting radio-tracking and GPS (Global Positioning System) in Daxing’an Mountains of China. Sables liked mature and elder forest, but it avoided uncovered and young growth land. In spring sables had strong selection to medium cover-degree forest, but it avoided widen ground and especial high cover-degree forest. On the contrary sables didn’t have the strong selection to shrubs cover-degree, but strong selection to dominant tree species, slope degree and slope direction, especially sable liked medium and lower slope. At the same time, sables had the strong selection to the log’s density and the crown’s cover-degree. Generally it avoided high elevation and lower slope land.
In this paper, the mutagencity of TNT was studied for mice and fruit flies. It was indicated that TNT had a great deal of mutagenic effect on the somatic cells and sexual cells of the animals used as the subjects of the experiment, and calculated that TNT would have a genetic harmfulness to human beings.
Based on the field observation on the parental behavior of Oriental White Stork (Ciconia boyciana) during their brooding period, this paper describes the breeding style, feeding behavior, water chicks, protect chicks, etc. A Ritual “behavior—Culmen Knocking/bill clattering” was observed and which is divided into three styles with deferent meanings. This behavior plays an important role during this season.
In this study “the leftest trace algorithm” was used to solve the trace of cells edge better. It also over-came the shortage that use sobel operator and laplace operator to detect the edge of wood cells. This realized the rapid extraction of the anatologic shape features in across compression and make possible the wood species could be characterized quantitatively.
This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest products has borne dual pressure because of the population explosion and growth of the domestic economy. A major contemporary strategy for sustainable forestry includes the promotion of the Forest Products Industry (FPI), the substitution of other materials for timber, and the encouragement of imports of timber and forest products. The author analyzes the effect of these policies on the market for timber and forest products. In addition, the difficulties encountered by most mid-to large—scale state-owned forest enterprises during the transition from a centrally-planned economy to a market economy are examined. Finally, the author points out the countermeasures and means for reform of these old forest enterprises with a view toward future prosperity of the market for timber and forest products.
Log centering accuracy depends on the computerized simulative level of its three-dimension outline. In this paper, the basic methods about distinguishing three dimensions outline of log by means of computerized simulation are discussed. It is suggested that straight lines or certain curves should be introduced to connect the separated points along some log generatrices. Taking bent logs for example verify the accuracy of computerized simulative method.
Based on the plot data from the investigation and the theory of forest ecology and ecological system, the site classification of the eastern forest region of Daxing’an Mountains was made by mean of mathematical method. The main factors were slope, thickness of soil layer, slope position and slope aspect. Grades of slope were used as the division standard for site type group. The slope aspect, slope position and thickness of soil layer were used as the division standards for site type. Altogether 7 site type groups and 15 main site types were determined the region. It provided reliable fundamental basis for the reasonable management and planting design in the area.