1991 Vol. 4, No. 3
Display Method:
1991, 4(3): 232-237.
Abstract:
The hydrochemical properties, seasonal changes and their balance of both semi-deciduous monsoon forest-latosol-granodiorite, granitite and mountain rain forest-lateritic yellow soil-potassium feldspar granite systems were studied at Jianfengling, Hainan Island, China based on the observations and chemical analyses on the major elements of precipitation, throughfall and stream. Elements content of the throughfall increased by 0.3~2.8 times more than that of the precipitation. More leaching quantity was found in the semideciduous monsoon forest than that of the mountain rain forest particularly K and N the most, and the leaching loss of Ca was less than the surface uptake of the plants in the mountain rain forest. The elements content of the stream were also less than that of the throughfall. The output content is more than input both in the Si, Ca, Mg and dried residue for the semi-deciduous monsoon forest and the Si, total acidity and total alkainity for the mountain rain forest. There are obviously seasonal changes in various hydro-elements content with seasonal changes of rainfall and forest plants and solubility of elements. It is pointed out that the precipitation and throughfall are an input source of the important elements of the tropical forest ecosystem, which has stronger function on the filtration, uptake and store. It is clear that hydrochemical regulating function of the mountain rain forest ecosystem is superior to that of the semi-deciduous monsoon forest ecosystem.
The hydrochemical properties, seasonal changes and their balance of both semi-deciduous monsoon forest-latosol-granodiorite, granitite and mountain rain forest-lateritic yellow soil-potassium feldspar granite systems were studied at Jianfengling, Hainan Island, China based on the observations and chemical analyses on the major elements of precipitation, throughfall and stream. Elements content of the throughfall increased by 0.3~2.8 times more than that of the precipitation. More leaching quantity was found in the semideciduous monsoon forest than that of the mountain rain forest particularly K and N the most, and the leaching loss of Ca was less than the surface uptake of the plants in the mountain rain forest. The elements content of the stream were also less than that of the throughfall. The output content is more than input both in the Si, Ca, Mg and dried residue for the semi-deciduous monsoon forest and the Si, total acidity and total alkainity for the mountain rain forest. There are obviously seasonal changes in various hydro-elements content with seasonal changes of rainfall and forest plants and solubility of elements. It is pointed out that the precipitation and throughfall are an input source of the important elements of the tropical forest ecosystem, which has stronger function on the filtration, uptake and store. It is clear that hydrochemical regulating function of the mountain rain forest ecosystem is superior to that of the semi-deciduous monsoon forest ecosystem.
1991, 4(3): 238-245.
Abstract:
This experiment is designed for probing bumper and steady yield management technique for bamboo shoot stands of Phyllostachys pubescens. The main object of the research is fertilization method. An orthogonal experimental design, with two replicates is adopted, where there are four factors with three levels for each i. e. (1) density of Ph. pubescens stands; (2) loosening depth; (3)dosage of fertilizer;(4) time and frequency of fertilization. For increasing the reliability of experimental results, CK plots, which are not given any fertilization treatment, are added.The spring bamboo shoot yields of ten treatments have been monitored continuously for five years and the data is analysed with objective analysis for orthogonal design and variance analysis for time split design respectively. The results show that the treatment No.2 (A1B2C2D2), No.4 (A2B2C2D3) and No.5 (A2B2C3D1) are the best matchs in the experiment, which can increase the yield about ten times in normal years. But the middle level management method (A2B2C2D2) is recommended in mountain area of middle and north subtropic region for bamboo shoot stands of Ph. pubescens, according to the results of comprehensive analysis. If this management method is adopted, the spring bamboo shoot yield can increase for about 20 tons·ha-1 every two years and can increase profit for 7000 Chinese Yuan (RMB).
This experiment is designed for probing bumper and steady yield management technique for bamboo shoot stands of Phyllostachys pubescens. The main object of the research is fertilization method. An orthogonal experimental design, with two replicates is adopted, where there are four factors with three levels for each i. e. (1) density of Ph. pubescens stands; (2) loosening depth; (3)dosage of fertilizer;(4) time and frequency of fertilization. For increasing the reliability of experimental results, CK plots, which are not given any fertilization treatment, are added.The spring bamboo shoot yields of ten treatments have been monitored continuously for five years and the data is analysed with objective analysis for orthogonal design and variance analysis for time split design respectively. The results show that the treatment No.2 (A1B2C2D2), No.4 (A2B2C2D3) and No.5 (A2B2C3D1) are the best matchs in the experiment, which can increase the yield about ten times in normal years. But the middle level management method (A2B2C2D2) is recommended in mountain area of middle and north subtropic region for bamboo shoot stands of Ph. pubescens, according to the results of comprehensive analysis. If this management method is adopted, the spring bamboo shoot yield can increase for about 20 tons·ha-1 every two years and can increase profit for 7000 Chinese Yuan (RMB).
1991, 4(3): 246-252.
Abstract:
A possibility study was conducted for controlling the degradation of productivity of Chinese Fir plantations by the help of its undergrowth. The results were as follows:1. The undergrowth develops quickly in Chinese Fir stands of closure 0.7. Its biomass and nutrient can accumulate 4~5 t/ha and 80~100 kg/ha respectively in 4~5 years and approximately 10~15 t/ha of organic matter can be obtained during a rotation by slash cutting tending.2. The content of nutrient in undergrowth is higher than that in trees. The undergrowth contributes more to nutrient cycling in the near-mature and mature stands.3. The undergrowth is favorable for the increase of the soil organic matter and soil nutrient content, especially available nutrient content.The results showed that it is possible to control the degradation of Chinese Fir plantations by the help of undergrowth and ecological management and self-fertilization of forest.
A possibility study was conducted for controlling the degradation of productivity of Chinese Fir plantations by the help of its undergrowth. The results were as follows:1. The undergrowth develops quickly in Chinese Fir stands of closure 0.7. Its biomass and nutrient can accumulate 4~5 t/ha and 80~100 kg/ha respectively in 4~5 years and approximately 10~15 t/ha of organic matter can be obtained during a rotation by slash cutting tending.2. The content of nutrient in undergrowth is higher than that in trees. The undergrowth contributes more to nutrient cycling in the near-mature and mature stands.3. The undergrowth is favorable for the increase of the soil organic matter and soil nutrient content, especially available nutrient content.The results showed that it is possible to control the degradation of Chinese Fir plantations by the help of undergrowth and ecological management and self-fertilization of forest.
1991, 4(3): 253-256.
Abstract:
The white-naped crane is an endangering species in the world. It's a kind of first-grade protected animal in China. It's distributed in six countries: breeding in U. S. S. R., Mongolia and China, overwintering in North Korea, South Korea, Japan and China. In China, its breeding places are in the lower reaches of the Wuyur River and Sanjiang Pingyuan in Heilongjiang Province, Tonyuu, Zhenliai in Jilin Province. In winter, it migrates to the lower reaches of the Yangtze River, Jiangsu, Anhui, Jiangxi, Hunan, Fujian and Taiwan Provinces. In Jun. 25, 1984, a crane marked "J17" was banded by the bander of Yamashina institute for ornithology, which migrated between China and Japan to breed in the spring of 1984~1986 in Zhalong through the banding observation and recovery. In Jun. 18, 1987, a baby of "J17" (banding number-Q00-0663, Red "61") was banded by the Sino-Japanese Cooperation. In Dec. 3, 1987, the "J17" family migrated to the overwintering place of Izumi in Japan. The White-naped crane's migration between the breeding place in China and overwintering place in Japan was recognized undoubtedly.
The white-naped crane is an endangering species in the world. It's a kind of first-grade protected animal in China. It's distributed in six countries: breeding in U. S. S. R., Mongolia and China, overwintering in North Korea, South Korea, Japan and China. In China, its breeding places are in the lower reaches of the Wuyur River and Sanjiang Pingyuan in Heilongjiang Province, Tonyuu, Zhenliai in Jilin Province. In winter, it migrates to the lower reaches of the Yangtze River, Jiangsu, Anhui, Jiangxi, Hunan, Fujian and Taiwan Provinces. In Jun. 25, 1984, a crane marked "J17" was banded by the bander of Yamashina institute for ornithology, which migrated between China and Japan to breed in the spring of 1984~1986 in Zhalong through the banding observation and recovery. In Jun. 18, 1987, a baby of "J17" (banding number-Q00-0663, Red "61") was banded by the Sino-Japanese Cooperation. In Dec. 3, 1987, the "J17" family migrated to the overwintering place of Izumi in Japan. The White-naped crane's migration between the breeding place in China and overwintering place in Japan was recognized undoubtedly.
1991, 4(3): 257-263.
Abstract:
The above-ground biomass of two components for 6 species of Eucalyptus, E. bakeri, E. smithii, E. radiata SSp. radiata, E. dives, E. macar-thurii and E. globulus ssp. globulus, was estimated two years after planting using samples taken from an experimental plantation which was designed as split-plots in 3 replicates in southwestern China. The plantation was established in three different spacings,0.5m×2m,1.0m×2m and 1.5m×2m. It was found from the preliminary results that there were significant differences in both growth rates and above-ground biomass between species. All species, except E. bakeri, gave the highest biomass production of both wood and leaves in fresh weight at the second spacing, 1.0m×2m. At this spacing E. smithii was ranked on the top reaching 4.5m in height and 5.2 cm in diameter and followed by E. globulus ssp. globulus in height of 4.1 m and ground-level diameter of 4.9cm, while E. bakeri was the last. Essential oil content of leaves was also analysed in the laboratory for each species. It was shown that all the six eucalypts could be managed in short rotation forestry for wood energy production which would bring about very good income to farmers in rural communities. E. smithii, which was for the first time grown in China, could become a better species than E. globulus ssp. globulus for oil and fuelwood production even the latter had become a land race in southwestern China.
The above-ground biomass of two components for 6 species of Eucalyptus, E. bakeri, E. smithii, E. radiata SSp. radiata, E. dives, E. macar-thurii and E. globulus ssp. globulus, was estimated two years after planting using samples taken from an experimental plantation which was designed as split-plots in 3 replicates in southwestern China. The plantation was established in three different spacings,0.5m×2m,1.0m×2m and 1.5m×2m. It was found from the preliminary results that there were significant differences in both growth rates and above-ground biomass between species. All species, except E. bakeri, gave the highest biomass production of both wood and leaves in fresh weight at the second spacing, 1.0m×2m. At this spacing E. smithii was ranked on the top reaching 4.5m in height and 5.2 cm in diameter and followed by E. globulus ssp. globulus in height of 4.1 m and ground-level diameter of 4.9cm, while E. bakeri was the last. Essential oil content of leaves was also analysed in the laboratory for each species. It was shown that all the six eucalypts could be managed in short rotation forestry for wood energy production which would bring about very good income to farmers in rural communities. E. smithii, which was for the first time grown in China, could become a better species than E. globulus ssp. globulus for oil and fuelwood production even the latter had become a land race in southwestern China.
1991, 4(3): 264-268.
Abstract:
The negative binomial, Neyman type A and Thomas distributions were fitted to the frequency distributions of the number of fecal groups per plot for semifree range Milu (Elaphurus davidianus)during Autumn and Winter. The results were counted on a systematic sample of 298 and 461 circular plots in 113 ha and 147ha of Da Feng Milu Reserve. The size of sample plots were 10 m2, 20m2 and 30m2. The negative binomial distribution was preferred to the results, the difference between aggregation of individuals was considered to be due to environmental causes rather than social factors. The negative binomial distribution was also suited to the frequency distribution of fecal groups on grassland and woodland in the two areas. The pellet-group density in woodland was higher than that in grassland, but the aggregate index in grassland was higher than that in woodland. These indicated that Milu prefered woodland rather than grassland during Autum and Winter. The individuals on grassland aggregated more closely than those in woodland. The aggregation of individuals of resting groups was higher than that of feeding groups. When fecal groups fitted negative binomial distribution in a habitat, the aggregate index of pellet-groups is relevent to the ratio of resting deer on the same habitat.
The negative binomial, Neyman type A and Thomas distributions were fitted to the frequency distributions of the number of fecal groups per plot for semifree range Milu (Elaphurus davidianus)during Autumn and Winter. The results were counted on a systematic sample of 298 and 461 circular plots in 113 ha and 147ha of Da Feng Milu Reserve. The size of sample plots were 10 m2, 20m2 and 30m2. The negative binomial distribution was preferred to the results, the difference between aggregation of individuals was considered to be due to environmental causes rather than social factors. The negative binomial distribution was also suited to the frequency distribution of fecal groups on grassland and woodland in the two areas. The pellet-group density in woodland was higher than that in grassland, but the aggregate index in grassland was higher than that in woodland. These indicated that Milu prefered woodland rather than grassland during Autum and Winter. The individuals on grassland aggregated more closely than those in woodland. The aggregation of individuals of resting groups was higher than that of feeding groups. When fecal groups fitted negative binomial distribution in a habitat, the aggregate index of pellet-groups is relevent to the ratio of resting deer on the same habitat.
1991, 4(3): 269-272.
Abstract:
This paper deals with the morphology of Kerria yunnanensis Ou et Hong under scanning electron microscope and light microscope. The supra-anal plate, brachia, anterior spiracle, posterior spiracle,dorsal spine, mouth-parts, antenna, vaginal pore, pervaginal pore clusters, marginal duct clusters and ventral duct clusters of this insect are described.
This paper deals with the morphology of Kerria yunnanensis Ou et Hong under scanning electron microscope and light microscope. The supra-anal plate, brachia, anterior spiracle, posterior spiracle,dorsal spine, mouth-parts, antenna, vaginal pore, pervaginal pore clusters, marginal duct clusters and ventral duct clusters of this insect are described.
1991, 4(3): 273-279.
Abstract:
Dictyoploca japonica Moore has one generation a year in Hubei Province. There are 5 instars in the larval stage. The 4th and 5th instar larvae have 2 types with either green or black color. The larvae feed on 38 species of plants and have 53 kinds of natural enemies. The relationship between the occurrence and environment of this insect is discussed. Control experiments showed that spray with various dilutions of 2.5% deltamethrin (Decis) 5000×, 2×108 spore of Beauveria bassiana, 25% Benzoylphenol urea No.1 500× and the dead body of 1×108 PIB D. japonica infected by NPV were very effective.
Dictyoploca japonica Moore has one generation a year in Hubei Province. There are 5 instars in the larval stage. The 4th and 5th instar larvae have 2 types with either green or black color. The larvae feed on 38 species of plants and have 53 kinds of natural enemies. The relationship between the occurrence and environment of this insect is discussed. Control experiments showed that spray with various dilutions of 2.5% deltamethrin (Decis) 5000×, 2×108 spore of Beauveria bassiana, 25% Benzoylphenol urea No.1 500× and the dead body of 1×108 PIB D. japonica infected by NPV were very effective.
1991, 4(3): 280-284.
Abstract:
The results of detections on the microbial contaminants in CPV agent for Pine Caterpillar (Dendrolimus spp.) showed that there were not enteric pathogenic microorganisms for human beings in the agent, the germ in the agent was not generative and the fungus in the agent could be controlled by inhibitors and disinfectants practiced in the test. The microbial contaminants in the agent were decreased by a thousand times when the pellet of the agent was treated with acetone,volume/wet-weight =1:1.A powder was easily obtained through treating the pellet of the agent with supersaturated-lactose-acetone in the ratio of 1:1. The results of bioassay showed that the treated and untreated agents did not indicate any evident difference in pathogenicity except the sample treated with sodium azide.
The results of detections on the microbial contaminants in CPV agent for Pine Caterpillar (Dendrolimus spp.) showed that there were not enteric pathogenic microorganisms for human beings in the agent, the germ in the agent was not generative and the fungus in the agent could be controlled by inhibitors and disinfectants practiced in the test. The microbial contaminants in the agent were decreased by a thousand times when the pellet of the agent was treated with acetone,volume/wet-weight =1:1.A powder was easily obtained through treating the pellet of the agent with supersaturated-lactose-acetone in the ratio of 1:1. The results of bioassay showed that the treated and untreated agents did not indicate any evident difference in pathogenicity except the sample treated with sodium azide.
1991, 4(3): 285-290.
Abstract:
Japanese pine sawyer (Monochamus alternatus Hope) is an important wood borer of pine tree and the vector of wood nematode. They can be trapped by attractants. The economical and suitable concentration for attraction is 1:3. The best effect is the No.1 attractant; less effects of the attractant are both mixed solvent of No.1 and No.2 and No.4. Insect attracted by attractant tree is over 17.8~54.9, 1.2~3.2, 5.3~5.8 times than those of control tree, fallen tree and withered tree respectively. Tree mortality is reduced by 2%~32% after applying attractants to the pine stand. The actual control effect is about 70%~95%, Applying attractant with oxidize rogor diluted solution (1:1) at the same time, the larvae will be killed about 62.4%~100%. A kind of parasitic wasp (Scleroderma guani Xiao et Wu) is released in pine stand (28 142 head per ha.), the control effect of contemporary generation is about 40%~50%, and will reach up to 69.6%~85.3% after three to four months.
Japanese pine sawyer (Monochamus alternatus Hope) is an important wood borer of pine tree and the vector of wood nematode. They can be trapped by attractants. The economical and suitable concentration for attraction is 1:3. The best effect is the No.1 attractant; less effects of the attractant are both mixed solvent of No.1 and No.2 and No.4. Insect attracted by attractant tree is over 17.8~54.9, 1.2~3.2, 5.3~5.8 times than those of control tree, fallen tree and withered tree respectively. Tree mortality is reduced by 2%~32% after applying attractants to the pine stand. The actual control effect is about 70%~95%, Applying attractant with oxidize rogor diluted solution (1:1) at the same time, the larvae will be killed about 62.4%~100%. A kind of parasitic wasp (Scleroderma guani Xiao et Wu) is released in pine stand (28 142 head per ha.), the control effect of contemporary generation is about 40%~50%, and will reach up to 69.6%~85.3% after three to four months.
1991, 4(3): 291-296.
Abstract:
Dioryctria yiai Mutuura et Munroe is a serious forest pest that damages staminate branch, cone and shoot of Pinus massoniana in China. The studies on the biology and control of this insect pest were carried out in Chunan County, Zhejiang Province in 1987~1990. D. yiai completes one generation a year with overwintering as larva in damaged staminate branch, cone and shoot. The paper describes the ecological relationships among the occurrence of the insect and forest climate, host and natural enemy. Experimental results showed that blacklight trap, spraying with the insecticides of SN-851 and 8302 in early spring were effective.
Dioryctria yiai Mutuura et Munroe is a serious forest pest that damages staminate branch, cone and shoot of Pinus massoniana in China. The studies on the biology and control of this insect pest were carried out in Chunan County, Zhejiang Province in 1987~1990. D. yiai completes one generation a year with overwintering as larva in damaged staminate branch, cone and shoot. The paper describes the ecological relationships among the occurrence of the insect and forest climate, host and natural enemy. Experimental results showed that blacklight trap, spraying with the insecticides of SN-851 and 8302 in early spring were effective.
1991, 4(3): 297-301.
Abstract:
After the fertilizers were applied to forest land in Populus ‘I-214' plantations, the average values of wood fibre length and width, wall thickness, relative crystallinity of cellulose and the chemical composition of a-cellulose showed a rising tendency but the microfibrillar angle of S2 layer of secondary wall of the wood cell a declining one (from 19.4°~18.3°). The values of the mechanical and physical properties of wood from treated or untreated plantations were different. But after they were checked by the analysis of variance, there were no obvious difference between them. The values of the physical properties of pulping and paper for chemical and mechanical pulping were similar except the yield rate (89.2%) was a bit high after the chemical preprocessing of heavily fertilized wood.
After the fertilizers were applied to forest land in Populus ‘I-214' plantations, the average values of wood fibre length and width, wall thickness, relative crystallinity of cellulose and the chemical composition of a-cellulose showed a rising tendency but the microfibrillar angle of S2 layer of secondary wall of the wood cell a declining one (from 19.4°~18.3°). The values of the mechanical and physical properties of wood from treated or untreated plantations were different. But after they were checked by the analysis of variance, there were no obvious difference between them. The values of the physical properties of pulping and paper for chemical and mechanical pulping were similar except the yield rate (89.2%) was a bit high after the chemical preprocessing of heavily fertilized wood.
1991, 4(3): 302-307.
Abstract:
Based on the statistical data published in China, 16 factors selected from 11 big Chinese cities were evaluated. The influence of each factor to the environment was analyzed by means of standard complex regression. Using principal component analysis and cluster analysis, the result obtained after the dependency of quantitative evaluation coincides with the model of environmental quantitative evaluation.
Based on the statistical data published in China, 16 factors selected from 11 big Chinese cities were evaluated. The influence of each factor to the environment was analyzed by means of standard complex regression. Using principal component analysis and cluster analysis, the result obtained after the dependency of quantitative evaluation coincides with the model of environmental quantitative evaluation.
1991, 4(3): 308-313.
Abstract:
Ten different kinds of artificial potting media used for the culture of Camellia japonica L. were mixed with vermiculite, saw-dust, river sand, peat and coal cinder. Two good mixed media, vermiculite:peat=2:1 and vermiculite:river sand: peat=10:5:1, in which the plants of C. japonica L. grew and bloomed excellently, have been obtained by means of three-year-culture experiments. Under the same level of applying micronutrients, seven fertilized treatments with different levels of N, P and K for the soiless culture were designed. The experiments showed that 23-12-15 formulation with high levels of N,P and K applied in spring and summer and 5-20-26 formulation with low level of N, and high levels of P and K applied in autumn and winter or 23-12-15 formulation with high levels of N, P and K applied once every twenty days throughout a year all can make the plants grow vigorously for a long time, bloom greatly and keep up their strong growing-potential in their limited potting media.
Ten different kinds of artificial potting media used for the culture of Camellia japonica L. were mixed with vermiculite, saw-dust, river sand, peat and coal cinder. Two good mixed media, vermiculite:peat=2:1 and vermiculite:river sand: peat=10:5:1, in which the plants of C. japonica L. grew and bloomed excellently, have been obtained by means of three-year-culture experiments. Under the same level of applying micronutrients, seven fertilized treatments with different levels of N, P and K for the soiless culture were designed. The experiments showed that 23-12-15 formulation with high levels of N,P and K applied in spring and summer and 5-20-26 formulation with low level of N, and high levels of P and K applied in autumn and winter or 23-12-15 formulation with high levels of N, P and K applied once every twenty days throughout a year all can make the plants grow vigorously for a long time, bloom greatly and keep up their strong growing-potential in their limited potting media.
1991, 4(3): 314-317.
Abstract:
This paper deals with shoot-culm growth of Phyllostachys dulcis in relation to the temperature and relative humidity in a newly established stand. The investigation was conducted in March and May, 1989. The main results of the nested multiple regression of meteorological factors to shoot growth show that the key factor affecting the shoot growth is temperature, while the shoot growth is not synchronized with rainfall.
This paper deals with shoot-culm growth of Phyllostachys dulcis in relation to the temperature and relative humidity in a newly established stand. The investigation was conducted in March and May, 1989. The main results of the nested multiple regression of meteorological factors to shoot growth show that the key factor affecting the shoot growth is temperature, while the shoot growth is not synchronized with rainfall.
1991, 4(3): 318-322.
Abstract:
The bionomical characteristics of forest insects in the tropics, such as generations, life-span, lasting period of oviposition, abnormal bionomics, diapause, dormancy, mimicry and pretending have been discussed in this paper. From the results, it was found that the multiplication in generations of the forest insects in the tropics is rapidly. The life-span and the lasting period of oviposition of the snout beetles are even longer and food capture in the larvae of cioninae are of special style. Some larvae like Hebomoia glaubippe L. (Pieridae) imitated the shape as cobra and some larvae like geometrids pretended itself as inflorescence of the host plants.
The bionomical characteristics of forest insects in the tropics, such as generations, life-span, lasting period of oviposition, abnormal bionomics, diapause, dormancy, mimicry and pretending have been discussed in this paper. From the results, it was found that the multiplication in generations of the forest insects in the tropics is rapidly. The life-span and the lasting period of oviposition of the snout beetles are even longer and food capture in the larvae of cioninae are of special style. Some larvae like Hebomoia glaubippe L. (Pieridae) imitated the shape as cobra and some larvae like geometrids pretended itself as inflorescence of the host plants.
1991, 4(3): 323-327.
Abstract:
Eleven species of ectomycorrhizal fungi on Pinus and Eucalyptus in south China have been found, among them, Pisolithus tinctorius and Scler-oderma polyrhizum which symbiotically grow with many species of Pinus and Eucalyptus are common species of ectomycorrhiza in the area. When the air temperature is above 20℃, the relative humidity is above 80% and abundant in precipitation, many carpophores of ectomycorrhiza fungi will appear. Under different natural conditions, the distribution of ectomycorrhiza fungi is distinctly different.
Eleven species of ectomycorrhizal fungi on Pinus and Eucalyptus in south China have been found, among them, Pisolithus tinctorius and Scler-oderma polyrhizum which symbiotically grow with many species of Pinus and Eucalyptus are common species of ectomycorrhiza in the area. When the air temperature is above 20℃, the relative humidity is above 80% and abundant in precipitation, many carpophores of ectomycorrhiza fungi will appear. Under different natural conditions, the distribution of ectomycorrhiza fungi is distinctly different.
1991, 4(3): 328-332.
Abstract:
It was found that juvenile trees of Masson Pine would be flowering at age of 2 and might greatly fruit at age 6. 87.3% of mature trees had cones, and 12.7% had not. Because of year variation in cone production, there appeared bumper harvest year and lean year alternately. Based on the observation of the distribution of cone production within crown, we found that the differences existed were relative to tree truck, cardinal directions and ages of branches. Site condition was one of the main factors affecting the fruitfulness. The fruitfulness law revealed in the paper would provided biological basis for management of seed orchard and seed-tree stand of Masson Pine.
It was found that juvenile trees of Masson Pine would be flowering at age of 2 and might greatly fruit at age 6. 87.3% of mature trees had cones, and 12.7% had not. Because of year variation in cone production, there appeared bumper harvest year and lean year alternately. Based on the observation of the distribution of cone production within crown, we found that the differences existed were relative to tree truck, cardinal directions and ages of branches. Site condition was one of the main factors affecting the fruitfulness. The fruitfulness law revealed in the paper would provided biological basis for management of seed orchard and seed-tree stand of Masson Pine.
1991, 4(3): 333-336.
Abstract:
Exogenous abscisic acid can make the activity of carppodium of Hippophae rhamnoides increase immediately and causes absciss of enormous fruit. But this absciss is not concentrated and an absciss of a large number of leaves is also caused. High concentration of abscisic acid is harmful for the growth of twigs and even makes it die, and low concentration of it is available for the growth of autumn twigs. The analysis of endogenous hormone of the fruit that trops naturally shows that with the development of absciss the abcisic acid and the class of kinin increase obviously, and also there is a little increase of somatotropin. This result tallies with what the absciss of fruit treated by exogenous hormone.
Exogenous abscisic acid can make the activity of carppodium of Hippophae rhamnoides increase immediately and causes absciss of enormous fruit. But this absciss is not concentrated and an absciss of a large number of leaves is also caused. High concentration of abscisic acid is harmful for the growth of twigs and even makes it die, and low concentration of it is available for the growth of autumn twigs. The analysis of endogenous hormone of the fruit that trops naturally shows that with the development of absciss the abcisic acid and the class of kinin increase obviously, and also there is a little increase of somatotropin. This result tallies with what the absciss of fruit treated by exogenous hormone.
1991, 4(3): 337-339.
Abstract:
The 0-1 time series analysis is a kind of binary time series analysis. It is a simple and useful mathematical method. The method was applied in the prediction of population trend of Dendrolimus punctatus Walker.
The 0-1 time series analysis is a kind of binary time series analysis. It is a simple and useful mathematical method. The method was applied in the prediction of population trend of Dendrolimus punctatus Walker.
1991, 4(3): 340-344.
Abstract:
The method ZBFL Ⅱ was used to classify the forest types in Maojingba forest region on the basis of three factors: dominant tree species, soil depth and slope exposure. 7 forest type groups contain 24 forest types in 2 forest vertical distribution zones were classified. Based on the evaluation, the managerial measures of each forest type was given.
The method ZBFL Ⅱ was used to classify the forest types in Maojingba forest region on the basis of three factors: dominant tree species, soil depth and slope exposure. 7 forest type groups contain 24 forest types in 2 forest vertical distribution zones were classified. Based on the evaluation, the managerial measures of each forest type was given.
1991, 4(3): 345-349.
Abstract:
The paper reported the Vc content changing rules in Hippopkae rhamnoides fruits that were taken from the natural forest grown in different geographical production places. Statistical analysis shows that the Vc content is related to the different geographical locations and altitudes of the production place, which obviously affect the Vc content. Before physiological maturity the Vc content in H. rhamnoides fruits increases sharply with the development of the fruit, and decreases slowly after physiological maturity. In the low elevation area of Beijing, it reaches the peak value in the first ten days of July. In the daily changing process, the peak Vc content occurs during 0~3 o'clock, and the content descends to the lowest during 12-15 o'clock. The fruits on the upper part of the canopy have the highest Vc content, while those at the middle part take the second, and those at the lower part have the lowest content. The fruits on the illuminated aspect possess more Vc content than those on the shaded aspect.
The paper reported the Vc content changing rules in Hippopkae rhamnoides fruits that were taken from the natural forest grown in different geographical production places. Statistical analysis shows that the Vc content is related to the different geographical locations and altitudes of the production place, which obviously affect the Vc content. Before physiological maturity the Vc content in H. rhamnoides fruits increases sharply with the development of the fruit, and decreases slowly after physiological maturity. In the low elevation area of Beijing, it reaches the peak value in the first ten days of July. In the daily changing process, the peak Vc content occurs during 0~3 o'clock, and the content descends to the lowest during 12-15 o'clock. The fruits on the upper part of the canopy have the highest Vc content, while those at the middle part take the second, and those at the lower part have the lowest content. The fruits on the illuminated aspect possess more Vc content than those on the shaded aspect.