2002 Vol. 15, No. 2
Huizhou's businessmen who came from the southern mountain area of Anhui Province, was a big business group in China's Ming and Qing dynasties. They were mainly engaged in four kinds of industry, i.e. tea, wood, salt and pawnbroking. Their capital accumulation and the subsequent prosperity were profited from the abundant forest resources. They attached great importance to culture and education, and also paid much attention to the protection of ecological environment and application of advanced forestry techniques in the exploitation and utilization of forest resources. While they managed the business of large amount of forest products from Chinese fir, bamboo, they also took full advantage of the Huizhou's rich natural resources, and they managed some plant resources in a scientific way such as tea, mulberry for silkworm, dry fruits, fruits, oil plants, fibrous plants etc. as well as developed the four treasures of study with Huizhou's features, i.e. writing brush, ink stick, ink slab, paper, thus, formed the Huizhou's forest sustainable development system, which is the valuable wealth of China's traditional forestry.
Monochamus alternatus, a major vector of the fatal disease PWN, emerges from dead pine woods from late May through late July, with the peak number mainly in mid June depending on where the woods come from Both male and female adults come out from the wood most frequently at 18:00 pm20:00 pm, contributing 28% to the total The ratio of eclosion and emergence varied among different locations, while the pine wood nematode, Bursaphelenchus xylophilus, negatively affects the ratio in the same wood source.
Ficus auriculata Lour and Ficus hispida Linn are important plant species in the tropical rainforest They provide foods and habitats for insects, birds and so on 20.088 samples of insects have been collected, including 8 orders, 21 families, 33 genera and 39 species on the F auriculata and 7 orders, 21 families, 32 genera and 37 species on the F hispida Common characteristics of insect communities show that pests species is abundant, the ratio is 94.6% 97.0%, but amount per species are limited and they belong mainly too Lepidoptera, Coleoptera and Homopyera etc Some insects not only eat fig fruits but also eat leaves, other eat leaves or branches In these insect communities, insects species are the most on the syconia, the ratio is about 54%, and amount is 93.1% 94.3% On the contrary, though species of beneficial insects are low, they have huge individual quantities The amount of pollination fig wasp is 86.4% 90.2% of all insects, and its successful pollination influences stability and development of fig trees communities.
Based on long term and position research, the temporal and spatial patterns and dynamic laws of soil water content in Min qin desert area were studied Some results are as follows: (1)The change of soil water content in different years is not obviously in Nitraria sibirica community and Tamarix ramosissima community, but it is great in Shifting sand dune, the maximum is 2.538%; (2)The season dynamic can be divided into three stages: accumulating, consuming and stable; (3)The vertical change of soil water content distribution is obviously, i e, decrease with the depth; (4)Compared with the bottom of slope and middle slope,the top of slope has higher soil water content, the maximum is 15.408%
The distribution of male cones, female cones, developing cones and mature cones, and hereupon, the ratio of male cones to female cones and the fruit bearing percentage in crown were studied in Zhicheng County of Hubei Province. The number of small female cones on the top of new shoot in early spring was counted. Analysis was made on the relationship between cone crop of a tree and the number of cones in annual sections of the crown and the number of cones in visible crown. It was shown that the number of cones in certain section and the number of visible cones in crown were very informative to the cone crop of a tree. Several ways. including the number of visible cones in crown, the most informative section and the number of immature cones in a tree, were tested to predict cone crop for Masson pine in the county. Joint estimation for regression coefficients of 1991-1993's models were tested. Three stable regression models for cone crop prediction on the basis of female cones, immature cones and mature cones, respectively, were established.
The effects of manganese and/or molybdenum on five indexes of physiology and biochemistry (contents of chlorophyll, net photosynthesis, dark respiration, activity of nitrate reductase and contents of soluble sugars) of Heptacodium miconioides leaves were studied. The results showed that manganese and/or molybdenum have great influence on them. Five indexes are the lowest under the deficiency of manganese and molybdenum and increase along with increase of densities of manganese or molybdenum. When the density of manganese is 0.05 mg·L-1 or molybdenum is 0.5 mg·L-1, contents of chlorophyll, net photosynthesis and dark respiration of Heptacodium miconioides leaves are the greatest respectively in the treatment of manganese or molybdenum. When the density of manganese or molybdenum is 5 mg·L-1, content of soluble sugars of Heptacodium miconioides leaves is the greatest respectively in the treatment of manganese or molybdenum. When the density of manganese is 0.05 mg·L-1 or molybdenum is 5 mg·L-1, the activity of nitrate reductase of Heptacodium miconioides leaves is the greatest respectively in the treatment of manganese or molybdenum. If the density of manganese or molybdenum is higher than the best suitable one (each index is the greatest in that), each index begins to descend. The patience of Heptacodium miconioides with high molybdenum is greater than that with high manganese. The interrelation between molybdenum and manganese is complicated. When molybdenum and manganese are low (0.5 mg·L-1), they are cooperative each other and when they are high(0.5 mg·L-1), they are incoordinate each other.
With the increasing consumption of pulps and timbers in the world, many exotic tree species have been introduced to China. Among these exotic species, Acacia mangium has become a major species in plantation forestry in tropical and subtropical China, which has properties of fast growing and nitrogen fixing. This paper reports the experimental results on the fertilization strategy. Effects of varied levels of N,P,K nutrients on the growth of A. mangium saplings in a water culturing system are demonstrated. In general, phosphorus (P) is the most important factor influencing the growth of A. mangium saplings, followed by potassium (K) and nitrogen (N) respectively. The less importance of nitrogen nutrient supports the fact that roots of A. mangium are able to transfer aerial N 2 to organic nitrogen with N fixing bacteria. The optimum fertilization lever of N,P,K is at the ratio of 190(N):25(P):160(K) mg·L-1 ?
Aimed at studying the influence of various patterns of site management on the productivity of Chinese fir (Cunninghamia lanceolata) plantation for generations, the second generation C. lanceolata plantation was established with 5 kinds of site preparation patterns on the cleared area of first generation C. lanceolata. The results showed that: (1) The pattern IV (Double slash) had the most benefits to the growth of 4 year old C. lanceolata of second generation, and had the most effects on reducing soil bulk specific gravity and raising soil pH value. This is the best site management pattern. (2) The pattern II (Whole tree harvest) was the worst. (3) The pattern I (No slash) had positive effect on the growth of C. lanceolata in 1 2 years after planting, but it had negative effect on soil fertility maintenance. (4) The pattern V (Stem and bark harvest + burning) was better than the pattern III (Stem + bark harvest), but the difference is not significant. (5) It is estimated that it will take about 90 months for the harvest residual to be decomposed to the 5% of the weight remains.
The dynamic change of tree height growth, DBH growth and volume growth in the stands of different Eucalyptus urophylla planting densities, the relationship between DBH growth and crown growth and the basic management density for E. urophylla timbers have been studied for 5.9 years in Laibin County of Guangxi Zhuang Municipality, China. The results indicate that density is negatively correlated with height growth, DBH growth and volume growth. (1)The height, DBH, the volume growth per stem of three planting densities is in the order of density 1 6672 2223 333 stem·hm-2. After 3.7 years the height in different seedlings scheme is in the order of (2 m×3 m)(1 m×6 m). The highest volume growth per stem is 1 667 stem·hm-2, and 2.04 times that of 3 333 stem·hm-2. (2)The order of volume growth per unit area of three planting densities is density 1 6672 2223 333 stem·hm-2 at 4.7 years but density 2.2221.6673.333 stem·hm-2 at 5.9 years. It means that the largest density does not reach the largest volume growth per unit area, that of the largest density 2 222 stem·hm-2 is 127.60 m 3·hm-2, and 1.17 times that of 3 333 stem·hm-2. (3)The relationship between DBH and crown could be described by using power equation C W=a× D b. The express equation is C W=0.472 4× D 0.671 5. (4)The basic management density is negatively correlated with DBH. By means of the correlation analysis, the basic management density for E. urophylla plantations is developed, and the suitable planting density for E. urophylla pulp timber is also determined.
Nineteen 400 m2 plots, including 7 plots in secondary forest and 4 plots in plantations of Pinus massoniana, P. elliottii and Albizia falcataria, respectively, were surveyed. A total of 163 species were recorded in these study plots, including two national protected species, Amentotaxus argotaenia and Artocarpus hypargyrea. The results of Hierarchy Clustering Analysis and Detrended Correspondence Analysis (DCA) showed similar trend: Secondary forest had the highest diversity, while the diversity of the plantations is relatively lower. Among the plantation communities, Albizia falcataria plantations had the highest diversity, followed by Pinus massoniana plantations, and the lowest is P.elliottii. The species composition and diversity varied among the forest communities. Secondary forests have richer species, but most are early successional pioneer species. The climax species or late successional species such as the species of Fagaceae, Magnoliaceae and Lauraceae are generally rare. Many native species are confined to secondary forest and are seldom to be found in plantations. The native species growing in the plantations are usually well dispersed by birds.
In 1993 and 1994,two inoculation experiments of clonal Eucalyptus grandis×E.urophylla tissue culture plants,inoculated in total of 16 ectomycorrhizal fungi from Australia and China,in tissue culture containers,were established at Zhenhai State Forest Farm,Kaiping,Guangdong,China.After planting,tree height(H),diameter at ground level(D)and diameter at breast heigh(DBH)were measured at regular intervals.From 6 months after planting,all indices(H,D,DBH)showed significant growth increase due to inoculation(P =0.01 or P =0.05).Based on Duncan's Multiple Range Test (method),isolates E4070,H4509,E4240,H6177,H4339,E4726,C9301,C9213 and C9203 clearly improved tree height and diameter,indicating that these ectomycorrhizal fungi were effective on Eucallyptus grandis×E.urophylla trees.
The activity of superoxide dismutase (SOD) and the concentration of chlorophyll, free proline (Pro), and malondialdehyde (MDA) of Camptotheca acuminata seedling under low temperature stress were studied. The results are as follows. The low temperature stress (4 ℃ and 8 ℃)decreased the concentration of chlorophyll. The SOD activity became lower at the beginning of stressing and higher later on. After 7 days' stressing, SOD activity became higher comparing to the former phase. This was quite different from other plant's reaction. With the stressing, the concentration of MDA became higher. At the same time, the concentration of Pro was also higher and higher. The results also show that there was a negative relationship between the SOD activity and the concentration of MDA and Pro. The concentration of MDA and Pro can be used as indexes to show how the seedling can endure the cold.
Remote sensing was used to monitor the vegetation dynamics of Bawangling forest area in Hainan Island.Three multitemporal TM data of same season in different years were processed using various techniques including spectral analysis,signature selection,and supervised classification to analyze the vegetation change.Bawangling vegetation change detection is an example which provides a feasible method for monitoring the tropical forest in Hainan Island.
The investigation shows that the fungus No.F9903 is much better than others. It grew faster, 1.222 cm per day under the most suitable temperature,30 ℃.Although it could be cultivated in the liquid within pH3 8,it grew bigger in the pH 7,the total weight of the mycelium up to 1.45 mg·mL-1,increase 131.8 times during cultivated period.Among 8 kinds of N sources (ammonium sulfate,ammonium nitrate,calcium nitrate,kalium nitrate,organic urea,ammonium tartrate,glycin,and glutamic acid),ammonium tartrate is the best in absorbing and assimilating this fungus,the total weight is up to 1.684 mg·mL-1,153 times of the originality.Next is the glutamic acid.Giving 8 kinds of C (glucose,fructose,sugar,maltose,ethanol,mannaol,dextrin,dissoluble starch)every one could be used,especially the fructose,the total weight of the mycelium up to 1.501 mg·mL-1 increase by 136 times.Among the sources of phosphor,kalium phosphate with two hydrogen atom (1 mg·mL-1)is the best,the total weight of the mycelium up to 1.256 mg·mL-1,increase by 114.2 times.
Based on the samplings of individuals from different clones and plots in a clone testing stand of Chinese fir (Cunninghamia lanceolata)at age 7,the paper made the estimation of clone rank correlation and clone repeatability on the height,DBH,volume and the wood density.The results showed that over 20 individuals per clone were sufficient to reliable growth test,30 individuals per clone were better.The number of individuals per plot was different among different numbers of individuals per clone.Fewer tree plots would be chosen if the number of individuals tested per clone were fewer,more tree plots would be chosen if the number was more.For the testing of wood density,the number of individuals per clone should be more than 6,but the sampling number of plot was 1,and that was the plus tree.
The damage of simulated acid rain to mesophyll cell was studied.The results showed that the damage to mesophyll cells occurred before visible damage to tree.These damage includes mesophyll cell being destroyed,contents of chlorophyll decreasing and permeability of plasma membrane increasing.
Under the condition of 26 ℃ and decortication, germination quotiety of seeds was improved with 31.7%. Comparing with hindering light. ABT 4 rhizogenesis powder has well applicable future in cultivating seedling of Schleichera oleasa, it effectual promoted the seeds'emerging and remaining quotiety with the thickness of 25 mg·kg-1, Germination quotiety, germination force and average germination time were markly advanced. By F check, germination index of S.oleasa' s seeds was improved,it proved that the seed is a kind of sensitive seeds to light. Compositive disposal has great advantage to S.oleasa' s seeds, this has great realistically value in lac production.
On the basis of the research of microgravity environment,space radiation on bio sample mutagenesis,the theoretical basis of hi tech breeding with space mutation technique is discussed.The application of space mutation technique in China's crop and flower new variety breeding is reviewed and the nondirective superiority of space mutation breeding and the possibility of successful space mutation breeding are discussed.A prospect for the application of space mutation breeding of flower in the future is described.
Current situation was generalized an analyzed on the information obtained from the research of population growth,structure dynamics,clonal growth pattern,morphological plasticity,physiological integration,and bionomic strategies of bamboo clonal population ecology.In the 21st century,the application of ecological high effective integration theories and its technologies on bamboo forest culture and utilization was discussed.
The nutrients,microorganisms and enzyme activities of soil in shrub wasterland,secondary artificial Eucalyptus camaldulensis forest land and soil erosion land were studied.The nutrients were poor in all land and amount of bacteria counted more than 79% of the total of soil microorganisms.The nutrients concentrations,microorganism numbers and enzyme activities of soil were middle and lower slopeupper slopesoil erosion land.
Callus was induced by embryos from mature seeds of Pinus serotina with MS medium contained 0.2 mg·L-1 of KT and 2.5 mg·L-1 of 2,4 D.After successive subculture and selection,six month old callus were transferred to a liquid medium with 0.2 mg·L-1 of KT and 0 5.0 mg·L-1 of 2,4 D and 200 mg·L-1 of LH for vibration culture,the suspension cultured cell lines were established with favorable dispersivity.A great amount of protoplasts were released from three month old cell suspension cultures,and protoplast yield and protoplast viability of suspension cells on linear phase are the highest under the enzyme combination cellulase R 10.2%+pectinase 0.25%?