Since the shelterbelt systems of 1,092,260 hm2 have been established for thirteen years from 1978, have formed 526,541 networks and protected 13,619,400 hm2 land in western part of Northeast region of China. According to the research work we did in the last five years, the results of research project showed that the shelterbelts had improved the environment significantly. A parameter of comprehensive effects of temperature, moisture and wind in the networks (Ec = 246.52−12.17E+0.58T+6.58U) which is an active method to estimate the effects of shelterbelt on farmland, is around 21.1–30.9mm/month improving the moisture state in dry season, helping the crop yield increasing on the average by 19.8%. The effective accumulated temperature (⩾ 10°C) increases by 71°C; the cropland area which suffered from wind and frost damage decreases by 80–90%, the grass coverage on the pastureland and grass production increases by 13% and by 49.4–72%, rough protein, rough fat and nitrogen-free extract of grass increase by 3.34%, 2.4% and 8.4% separately. A large number of fixing sand plantation has been established for over thirty years on shifting in Kerqin sand land; most sand duncs were stable; a great results got from 2,000hm2, experimental area in this region; the atmospheric transport dust decrease by 2,253t/y; absorbed dust 11.1t/ y and people’s eyes sick decrease by 75%. The sandy ecological system develops a relative stable plantation system, the grass, shrubs increase to 200 species from 20 species, insects increase to 400 from 30 species, birds to 60 species and other animals increase to 20 from a few species, the fungi increase to over 200 species.
Seed deterioration is an irresistible physiological phenomenon. The aim to study seed deterioration is to see if seed deterioration can be retarded artificially and the higher seed vigor of fine varieties be maintained. The change of seed deterioration occurs in almost every system, and affects many kinds of enzyme and almost all organelle, as a result, the seed loses its vigor. The reason of seed deterioration and the lost of seed vigor are mainly studied and discussed in this paper. According to the external and internal two kinds of theory advanced by E. H. Roberts, Much deep discussions are made from the view of biochemistry.
After 14 year’s growth observation on the plant growth, it was found that obvious segregation appeared among the haploid pollen plants obtained from anther culture ofPopulus Xiaohei T.S. Hwany ex C. Wang et Tung in vitro. By vegetative propagation, 19 clones were selected and field contrast test was carried out. Statistical analysis result showed a significant difference in volume production. They are superior clones which could be selected from among the pollen plants for utilization. A haploid breeding procedure is suggested in the paper.
The key for puparia of the three species of larch-cone-flics (Strobilomyia) is developed based on their external morphological characteristics on anal (posterior) part which includes segmental protrusions and background texture. Some characteristics which are only visible under scanning microscope are also included even though they are supplementary in this key. Those three commonly found larch-cone-infestinganthomgiids arestrobilomyia melania, S. infrequens andS. laricicola.
In this paper, it is studied that the growth characters of the progeny of 16 provenance oflarix gmelinii within the all 13 experimental sites by means of the analysis of variance, provenance stability, productivity index, rank correlation, synthetic index selection and PCA.The provenances were divided into three patterns: The first type have low and steady productivity; The second type have high but unsteady productivity; The third type is between the productivity of the first and second type. Through the analysis on the feasibility and the reliability of the provenance early selection, the best provenances which lie in the southeast of the Xiaoxingan Mt. are regarded as the best and suitable for a large afforestation areas ofLarix gmelinii. Then in the north of Xingan Mt., the local or the northwest provenances of the Xiaoxingan Mt. should be used. The genetic gain was calculated on the basis of the provenance heritability and the utilization of the best provenance were evaluated in this paper.
This article introduces the history and development of log grapple in China. According to the special conditions of Chinese forest areas, we have selected log grapple driven by electric drum, and have analyzed and calculated its parameters theoretically. This is the first log grapple driven by an electric drum made successfully in China. The Model DZ1 log grapple has a large closing force, works safely and is suitable for the special forest working conditions in China.
5, 10, 15, and 20 year oldLarix gmelini andBetula platyphylla were used as pulping raw material in the research. The examination of youngL. gmelini andB. Platyphylla fibrous structures showed that the fiber length and ratio of length to width of 5 years oldL. gmelini noticeably differed from that of matureL. gmelini. but that of 5 year oldB. platyphylla were nearby equal to that of matureB. platyphylla. The research results indicated that 15 years oldB. platyphylla and 20 year oldL. gmelini were best suited to pulping among the eight experimental raw materials; 10 years oldB. platyphylla and 15 year oldL. gmelini were optimal to the ratio of beating degree increment and corresponding beating time. The pulp characteristics of 15 year old B. platyphylla and 20 year oldL. gmelini were similar to those of mature wood, and it was feasible to consider 15 years toB. platyphylla and 20 years toL. gmelini as their rotation period; 10 years and 15 years as their thinning cycles for the papermaking forest base.
High dimensional stable particleboards could be produced by usisng saturated steam treated wood chip at elevated pressures. Sample Particleboards were made from wood chip of Birch (Platyphylla). The component changes of steam treated wood chip were analysed by infrared. Infrared spectra demonstrated that the hemicelluloses in steam treated chip were less than those in untreated chip. This is one of the main reasons why steam treatment could improve particleboard stability. The free radical concentration of steam treated chip surfaces was analysed by ESR spectroscopy. The results showed that free radical concentration of treated chip surface was higher than that of untreated chip surface. The glueyness of chip increased and particleboard resin content decreased.
The amount of CCA fixed in the southern pine treated with CCA have been evaluated. The conclusions from these experiments are:with the timber density increases, the retention based on weight/weight will decrease, but the retention based on weight/volume will be almost constant. Retention by weight would be more influential than by volume.
The stepwise stability constants of coordination compounds from sulfonated sheoak tannin with metal ions have been determined by pH potential method with catechol as model compounds at 20°C and constant ionic strength.
Heilongjing (China) and Alberta (Canada) provinces are situated at the same latitude, with similar nature conditions. Mammals in Alberta account for 87 species and in Heilongjing, 97 spesies, among which a number of orders, families and species are in common. Continents of Eurisia and North America histoi cally were connected and separated for several times, so there are a number of animal forms in common, among them the similarity of herbivores is rather high. The similarity index of cervidae is 0.54. Other orders with comparatively similar compiosition arc Insevtivora, Chiroptera and Lagomorpha. In two orders, there are no common species. In these two regions, due to historical reasons, a number of specific genera and species were formed.
Through the polyacrylamide gel electrophoresis analysis of thirty-two needle samples of ninty-years oldpinus koraiensis in Harbin, seven typies of zone and distribution of the zone frequency, and some objective fact of heredity and variation were determined. These informations can be used as reference materials in the research of heredity and variation ofpinus koraiensis.
Using The Electric Fertilization Apparatus which was made by the Forestry Instiute of Jilin City, the mechanism of the electric field on the physical-chemical characteristics of soil, in this paper were studied. The preliminary conclusion is that the amount of chemical fertilizer may be saved under the effect of electricity.
The geographical distribution and the abundance of Moose (Alces alces) population were studied in Northeastern China between 1985 and 1987, 309 trails on the snow crossing the 2, 446km sampling lines were counted. The Moose range had been shrunked to northwest for 100–200 km since 1976, and at present they covered an area about 190,000 km2. The densities varied from 0.0187 Mooses/km2 to 0.1226 Mooses/km2 and the average was 0.0519 Mooses/km2. The Moose population size was 9, 955 ± 397 Mooses (α = 0.2, P = 84.5%), about 7000 of them was distributed in Daxinganling Mountains and the others were in Xiaoxinganling Mountains. The present population had decreased to 53.4% in 1976, and the annual decrease rate was 6.27%. At present, Moose population is likely rare in China and should be strictly protected.
The physical mechanism of resistance of poplar againstCryptorrhynchus lapathi L. is directly correlated with the morphological structure of bark, concerning the following 5 aspects: 1. It is correlated with whether surface bark of larva transvered tunnel crack or not, early or late. Those that do not crack or crack late are susceptible strains while those that crack early are resistant strains. 2. It is correlated with thickness of cork layer. Thick cork layer can increase resistance against pest while thin one is more susceptible to pest attack. 3. It is related with age of tree. Trees at the age of 1–2 possess immunity to the pest, at 3–4 are relatively resistant, at 5–8 are susceptible and over 9 are more resistant. 4. It is also correlated with the rate of trees healing round the holes of larva tunnels. Those healing faster arc resistant while those healing slower are susceptible. 5. It is related with the number of various scars on bark surface.