2000 Vol. 13, No. 2
Display Method:
2000, 13(2): 111-117.
[Abstract]
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Abstract:
A trial has been laid out,which is by the same orthogonal design with 3 factors including keeping the height of mother offset,treating the buds on its culm base and applying with BA+NAA of various concentration,and 3 levels in three different location for searching the proper establishment and management technology on promoting sub branches from adventitious buds,the best propagating materials in the field,of Dendrocalamopsis oldhami(Nanping City), Bambusa multiplex(Fuyang City)and Bambusa textilis(Guangzhou City)in their cuttings-garden.The results showed that the proper technology for establishing cuttings-garden is(1)keeping the mother offsets with 7 internodes after chopping their top,(2)damaging all buds on its culm base and(3)applying 5 times of MS nutrient solution with BA+NAA of various concentration according to the species i.e.2 mg BA+1 mg NAA per liter for D. oldhami, 10 mg BA +1 mg NAA per liter for B. multiplex, 5 mg BA +1 mg NAA per liter for B. textilis,from mid April to mid-August,and its dosage is l liter·clump-1 ·time-1,which can harvest 142 500,114 000,54 000 sub branches·hm-2 ·year-1 for D. oldhami,B. multiplex and B. textilis respectively.The sustainable management technology for D. oldhami is(1)during later-middle shooting stage,keeping 2 or 3 new culms per clump i.e.making the culm age structure of clump as 1 year old∶2 year old=2∶1,(2)chopping their top in next early spring and keeping the culms with 7 internode height,which will give 160 500 sub branches·hm-2 sustainablely in each year.
A trial has been laid out,which is by the same orthogonal design with 3 factors including keeping the height of mother offset,treating the buds on its culm base and applying with BA+NAA of various concentration,and 3 levels in three different location for searching the proper establishment and management technology on promoting sub branches from adventitious buds,the best propagating materials in the field,of Dendrocalamopsis oldhami(Nanping City), Bambusa multiplex(Fuyang City)and Bambusa textilis(Guangzhou City)in their cuttings-garden.The results showed that the proper technology for establishing cuttings-garden is(1)keeping the mother offsets with 7 internodes after chopping their top,(2)damaging all buds on its culm base and(3)applying 5 times of MS nutrient solution with BA+NAA of various concentration according to the species i.e.2 mg BA+1 mg NAA per liter for D. oldhami, 10 mg BA +1 mg NAA per liter for B. multiplex, 5 mg BA +1 mg NAA per liter for B. textilis,from mid April to mid-August,and its dosage is l liter·clump-1 ·time-1,which can harvest 142 500,114 000,54 000 sub branches·hm-2 ·year-1 for D. oldhami,B. multiplex and B. textilis respectively.The sustainable management technology for D. oldhami is(1)during later-middle shooting stage,keeping 2 or 3 new culms per clump i.e.making the culm age structure of clump as 1 year old∶2 year old=2∶1,(2)chopping their top in next early spring and keeping the culms with 7 internode height,which will give 160 500 sub branches·hm-2 sustainablely in each year.
2000, 13(2): 118-122.
Abstract:
This paper deals with storage methods,storage temperatures and changes of chemical substances during storage of Chinese chestnut(Castanea mollissima cv.Yanfeng and C. mollissima cv.Hongyouli).The results were as follow:(1)When the chestnut was stored at the temperature of 0～2 ℃,the weight loss was serious,the seed shrank and sprouted at the later stage of storage.(2)When the chestnut was stored at MA storage condition,the weight loss was less and the seed was kept freshly,but the sprouting of the seed still occurred at the later stage.(3)CA storage could control the weight loss and sprouting of the seed effectively,but the storage cost was too high and the storage technique was too strict to operate.(4)Based on MA condition,the storage temperature was regulated to-0.5～1.5 ℃,0～2 ℃ and-2～-4 ℃ at the initial,middle and later storage stage respectively,the chestnut was fresh,the sprouting was prevented and the decomposition of starch and protein were slow,so the quality and flavor of the stored chestnut was kept very well.By this storage method,Chinese chestnut can be stored for more than 8 months,the rate of weight loss,rot and sprouting were 2.0%～2.3%,0.6%～1.6% and 0 respectively.
This paper deals with storage methods,storage temperatures and changes of chemical substances during storage of Chinese chestnut(Castanea mollissima cv.Yanfeng and C. mollissima cv.Hongyouli).The results were as follow:(1)When the chestnut was stored at the temperature of 0～2 ℃,the weight loss was serious,the seed shrank and sprouted at the later stage of storage.(2)When the chestnut was stored at MA storage condition,the weight loss was less and the seed was kept freshly,but the sprouting of the seed still occurred at the later stage.(3)CA storage could control the weight loss and sprouting of the seed effectively,but the storage cost was too high and the storage technique was too strict to operate.(4)Based on MA condition,the storage temperature was regulated to-0.5～1.5 ℃,0～2 ℃ and-2～-4 ℃ at the initial,middle and later storage stage respectively,the chestnut was fresh,the sprouting was prevented and the decomposition of starch and protein were slow,so the quality and flavor of the stored chestnut was kept very well.By this storage method,Chinese chestnut can be stored for more than 8 months,the rate of weight loss,rot and sprouting were 2.0%～2.3%,0.6%～1.6% and 0 respectively.
2000, 13(2): 123-128.
Abstract:
Based on the contrast experiment of the felling management,the content of nitrogen and organic carbon in soil were measured in a tropical montane rainforest of Bawangling,Hainan Island.The results showed that the organic carbon and nitrogen were 108.91 t·hm-2 and 9.58 t·hm-2 respectively in the soil layer of 100 cm of the virgin forest,and 77.6% of organic carbon and 73.8% of nitrogen were stored in surface soil of 50 cm.Five months later after felling tropical montane rainforest by the intensity of 30% and 50%,the soil carbon storage declined by 4.5% and 5.3% respectively compared with the previous virgin tropical forest.C/N ratio of the soil on the 30% harvest plot was close to that in the virgin forest.
Based on the contrast experiment of the felling management,the content of nitrogen and organic carbon in soil were measured in a tropical montane rainforest of Bawangling,Hainan Island.The results showed that the organic carbon and nitrogen were 108.91 t·hm-2 and 9.58 t·hm-2 respectively in the soil layer of 100 cm of the virgin forest,and 77.6% of organic carbon and 73.8% of nitrogen were stored in surface soil of 50 cm.Five months later after felling tropical montane rainforest by the intensity of 30% and 50%,the soil carbon storage declined by 4.5% and 5.3% respectively compared with the previous virgin tropical forest.C/N ratio of the soil on the 30% harvest plot was close to that in the virgin forest.
2000, 13(2): 129-133.
Abstract:
According to the data of shrubs from 68 plots,there are 15 community types in the Three Gorges Reservoir area.As for the common shrubs,such as: Viburnum propinquum community, Cotinus coggygria community, Quercus fabri community,the richness index is relatively high both in shrub layer and in herb layer,the richness index in Myricaria laxiflora community, Distylium chinense community, Salix variegata community and S. variegata+M. laxiflora community is relatively low.The diversity index in V. propinquum community is relatively high both in shrub layer and in herb layer,but it is relatively low in Q. serrata var.brevipetiolata community, Coriaria nepalensis community and Vitex negundo community.The regularity of trend of community diversity along elvation has not been found,maybe human disturbance is one of the main reasons.
According to the data of shrubs from 68 plots,there are 15 community types in the Three Gorges Reservoir area.As for the common shrubs,such as: Viburnum propinquum community, Cotinus coggygria community, Quercus fabri community,the richness index is relatively high both in shrub layer and in herb layer,the richness index in Myricaria laxiflora community, Distylium chinense community, Salix variegata community and S. variegata+M. laxiflora community is relatively low.The diversity index in V. propinquum community is relatively high both in shrub layer and in herb layer,but it is relatively low in Q. serrata var.brevipetiolata community, Coriaria nepalensis community and Vitex negundo community.The regularity of trend of community diversity along elvation has not been found,maybe human disturbance is one of the main reasons.
2000, 13(2): 134-140.
Abstract:
Forest formation was selected to be basic unit of site quality evaluation of natural tropical mountainous rain forest in Hainan Island.The average dominant tree height and DBH of dominant tree species group in forest formation were selected to be dependent variable and independent variable of site quality evaluation model.Standard DBH is 40 cm by quantitative analysis.Site quality evaluation model of three formation type,which are Podocarpus imbricatus Blume, Keteleeria hainanensis Chun et Tsiang, Quercus championi Benh. forest; Dacrydium pierrei Hickel, Syzygium areiocladum Merr Perry, Xanthophyllum hainanense Hu forest;and Castanopsis fabri Hance, Schefflera octophylla(Lour.)Harms, Endospermum chinense Benth forest,were established.The adaptability of the model was tested and the result showed that the difference between theoretical value and investigating value was not obvious.So the site index table was established.
Forest formation was selected to be basic unit of site quality evaluation of natural tropical mountainous rain forest in Hainan Island.The average dominant tree height and DBH of dominant tree species group in forest formation were selected to be dependent variable and independent variable of site quality evaluation model.Standard DBH is 40 cm by quantitative analysis.Site quality evaluation model of three formation type,which are Podocarpus imbricatus Blume, Keteleeria hainanensis Chun et Tsiang, Quercus championi Benh. forest; Dacrydium pierrei Hickel, Syzygium areiocladum Merr Perry, Xanthophyllum hainanense Hu forest;and Castanopsis fabri Hance, Schefflera octophylla(Lour.)Harms, Endospermum chinense Benth forest,were established.The adaptability of the model was tested and the result showed that the difference between theoretical value and investigating value was not obvious.So the site index table was established.
2000, 13(2): 141-146.
Abstract:
The nitric oxide(NO)content and nitric oxide synthase(NOS)activity in seedlings varied with the growing period of Alnus cremastogyne. In the initial stage,NO content and NOS activity were low. They gradually raised until the peak of the growth. When leaf began aged,the NO content and NOS activity turned to low level. The changes of nitrate reductase(NR)and glutamine synthase(GS)activities in growing period were similar to the NOS,but the maximum activity of NR appeared earlier than that of NOS. The former was in June and the latter was in July. GS maximum activity appeared in September. When leavies were directly exposed to NO(5～30 μmol·L-1),NO content and NOS activity appeared obvious increase. NR activity in seedling leaf(in vivo)raised,and in young tree leaf(in vitro)reduced. Treated with NO the nitrate reductase(NR)activity in branch’s leaf cultivated in KNO3 solution(0.05 mol·L-1)obviously raised. If branch were directly cultivated in KNO3 solution,NO content and NOS activity appeared increase except for NR activity. The results showed that there exist relationship between the level of NO and NOS,and growing of A. cremastogyne. NO related to nitrate reduction.
The nitric oxide(NO)content and nitric oxide synthase(NOS)activity in seedlings varied with the growing period of Alnus cremastogyne. In the initial stage,NO content and NOS activity were low. They gradually raised until the peak of the growth. When leaf began aged,the NO content and NOS activity turned to low level. The changes of nitrate reductase(NR)and glutamine synthase(GS)activities in growing period were similar to the NOS,but the maximum activity of NR appeared earlier than that of NOS. The former was in June and the latter was in July. GS maximum activity appeared in September. When leavies were directly exposed to NO(5～30 μmol·L-1),NO content and NOS activity appeared obvious increase. NR activity in seedling leaf(in vivo)raised,and in young tree leaf(in vitro)reduced. Treated with NO the nitrate reductase(NR)activity in branch’s leaf cultivated in KNO3 solution(0.05 mol·L-1)obviously raised. If branch were directly cultivated in KNO3 solution,NO content and NOS activity appeared increase except for NR activity. The results showed that there exist relationship between the level of NO and NOS,and growing of A. cremastogyne. NO related to nitrate reduction.
2000, 13(2): 147-152.
Abstract:
The photosynthetic characteristic and its relation to eco-physiological factors for poplar tree on beach land along the Yangtze River were studied. The main results were as follows:(1)The changes of net photosynthetic rate(Pn)in a clear day showed a double peak curve,two peak values appear at 10:00 and 14:00;(2)There was a close relation between the net photosynthetic rate and the age of tree. The Pn of two year old trees was more than that of seven-year-old trees;(3)The net photosynthetic rate on different elevations were different. In high elevation the growth condition of poplar is better than that in low elevation;(4)Under different densities,the rates of solar energy utilization were different. Small density or large row spacing is beneficial to rise the Pn. Meanwhile large row spacing and small spacing in the rows is beneficial to rise the rate of solar utilization;(5)The Pn was affected by both ecological factors and physiological factors,related to photon flux density,temperature,relative humidity and transpiration rate.
The photosynthetic characteristic and its relation to eco-physiological factors for poplar tree on beach land along the Yangtze River were studied. The main results were as follows:(1)The changes of net photosynthetic rate(Pn)in a clear day showed a double peak curve,two peak values appear at 10:00 and 14:00;(2)There was a close relation between the net photosynthetic rate and the age of tree. The Pn of two year old trees was more than that of seven-year-old trees;(3)The net photosynthetic rate on different elevations were different. In high elevation the growth condition of poplar is better than that in low elevation;(4)Under different densities,the rates of solar energy utilization were different. Small density or large row spacing is beneficial to rise the Pn. Meanwhile large row spacing and small spacing in the rows is beneficial to rise the rate of solar utilization;(5)The Pn was affected by both ecological factors and physiological factors,related to photon flux density,temperature,relative humidity and transpiration rate.
2000, 13(2): 153-159.
Abstract:
The concentration experiment and orthogonal design experiment of BR,GA3,PP333,KH2PO4 and H3BO3 were conducted by foliar spraying for flowering and fruit bearing in Chinese chestnut. The results showed that,the differences of chemical regulators,concentrations and their combinations have various impacts on the number of fruit bearing shoots per mother shoot,the length of fruit bearing shoot,the number of female inflorescence per fruit bearing shoot,the number of male flower shoots per mother shoot,weight per nut,percentage of 3 nuts per involucre and percentage of empty-shell chestnut,respectively. The optimum treatment of chemical regulation for enhancing the number of female flowers and the fruit yield,as well as for reducing the percentage of empty-shell chestnut is BR 0.01 mg·L-1 +PP333 1 000 mg·L-1 +KH2PO4 7 500 mg·L-1 +H3BO3 5 000 mg·L-1 according to the results obtained by chemical regulating experiments,which can raise the number of fruit bearing shoots per mother shoot from 1.2 to 2.833,enhance the number of female inforescence per fruit bearing shoot from 1.567 to 1.8 and drop the average percentage of empty-shell chestnut from 30.70% to 9.03%.
The concentration experiment and orthogonal design experiment of BR,GA3,PP333,KH2PO4 and H3BO3 were conducted by foliar spraying for flowering and fruit bearing in Chinese chestnut. The results showed that,the differences of chemical regulators,concentrations and their combinations have various impacts on the number of fruit bearing shoots per mother shoot,the length of fruit bearing shoot,the number of female inflorescence per fruit bearing shoot,the number of male flower shoots per mother shoot,weight per nut,percentage of 3 nuts per involucre and percentage of empty-shell chestnut,respectively. The optimum treatment of chemical regulation for enhancing the number of female flowers and the fruit yield,as well as for reducing the percentage of empty-shell chestnut is BR 0.01 mg·L-1 +PP333 1 000 mg·L-1 +KH2PO4 7 500 mg·L-1 +H3BO3 5 000 mg·L-1 according to the results obtained by chemical regulating experiments,which can raise the number of fruit bearing shoots per mother shoot from 1.2 to 2.833,enhance the number of female inforescence per fruit bearing shoot from 1.567 to 1.8 and drop the average percentage of empty-shell chestnut from 30.70% to 9.03%.
2000, 13(2): 160-166.
Abstract:
Research on rural landscape planning was conducted at Nanhua Farm,which is located in the south of the Leizhou Peninsula,Guangdong Province.Based on the soil nutrient status,rainfall and mean yield of major crops,the soil suitability and land adaptability were evaluated An artificial neural network was introduced as and alternative for modeling the landscape planning.A model was developed using back-propagation as the learning procedure,the sigmoid function as the transfer function and 6 patch types and its number of three phases as input factors. 3 optimum planning schemes were selected by using the model.Strategies were proposed for improving divesity and heterogeneity,productivity and sustainability within the system through the planning scheme.
Research on rural landscape planning was conducted at Nanhua Farm,which is located in the south of the Leizhou Peninsula,Guangdong Province.Based on the soil nutrient status,rainfall and mean yield of major crops,the soil suitability and land adaptability were evaluated An artificial neural network was introduced as and alternative for modeling the landscape planning.A model was developed using back-propagation as the learning procedure,the sigmoid function as the transfer function and 6 patch types and its number of three phases as input factors. 3 optimum planning schemes were selected by using the model.Strategies were proposed for improving divesity and heterogeneity,productivity and sustainability within the system through the planning scheme.
2000, 13(2): 167-176.
Abstract:
The test stands were established at five sites in the central and north subtropical region of China in order to determine the suitable initial planting densities of industrial timber plantation of slash pine and loblolly pine.According to 6～7 years’ field survey results the effects of initial density on the stand factors of individual tree growth,population development,tree form and wood property,and the changes of growth factors due to the difference of stand development process were analyzed.Based on the comprehensive consideration of biological and economic factors,the initial planting density patterns is suggested as follows:with the site index of 14～18,the densities are 2 000～1 333·hm-2 for slash pine,1 667～1 111·hm-2 for loblolly pine.The densities of 2 000～1 667·hm-2 are adopted for unthinning pulping timber stands,or compound target of pulping timber and middle dimension timber with thinning;1 667～1 111·hm-2 and thinning are adopted for cultivation of middle and large dimension timber. Meanwhile,the necessary cultural measures are put forward for the realization of above management goals.
The test stands were established at five sites in the central and north subtropical region of China in order to determine the suitable initial planting densities of industrial timber plantation of slash pine and loblolly pine.According to 6～7 years’ field survey results the effects of initial density on the stand factors of individual tree growth,population development,tree form and wood property,and the changes of growth factors due to the difference of stand development process were analyzed.Based on the comprehensive consideration of biological and economic factors,the initial planting density patterns is suggested as follows:with the site index of 14～18,the densities are 2 000～1 333·hm-2 for slash pine,1 667～1 111·hm-2 for loblolly pine.The densities of 2 000～1 667·hm-2 are adopted for unthinning pulping timber stands,or compound target of pulping timber and middle dimension timber with thinning;1 667～1 111·hm-2 and thinning are adopted for cultivation of middle and large dimension timber. Meanwhile,the necessary cultural measures are put forward for the realization of above management goals.
2000, 13(2): 177-181.
Abstract:
The data from 44 temporary plots and 52 fixed plots of 17～25 years old Cunninghamia lanceolata plantations in Jiangxi Province were used to study the influence of site,age and reserved density on the wood property of C. lanceolata. The results showed that the dominant factor influencing the formation of middle and large dimension wood is site,followed by reserved density and cultivation duration.It is suitable to cultivate middle dimension wood when the site index is no less than 16,the reserved density is 1 050～1 350 trees per hectare,and the age of tree is between 20～22 years old. For cultivating large dimension wood,the management density should be lower and the cultivation duration should be longer.
The data from 44 temporary plots and 52 fixed plots of 17～25 years old Cunninghamia lanceolata plantations in Jiangxi Province were used to study the influence of site,age and reserved density on the wood property of C. lanceolata. The results showed that the dominant factor influencing the formation of middle and large dimension wood is site,followed by reserved density and cultivation duration.It is suitable to cultivate middle dimension wood when the site index is no less than 16,the reserved density is 1 050～1 350 trees per hectare,and the age of tree is between 20～22 years old. For cultivating large dimension wood,the management density should be lower and the cultivation duration should be longer.
2000, 13(2): 182-187.
Abstract:
Close relations existed between the pine forest fire and the epidemic spread of pine wilt disease(PWD).The adults of Monochamus alternatus emerged from the fire injury pine trees carried an average of 7 364 nemateodes,which will infect the healthy pines and causes the mortality of pine and epidemic spread of PWD.There are 3 types of PWD associated with the fire of pine forest,i.e.PWD occurs in the same year when forest is burned,PWD occurs in the next year after forest fire,and occurs several years later.It is an effective method for controlling PWD by clear-cutting all the fire dead pines parasitized by beetles and nematodes according to the results of studies.4 new methods can be used in the practice of breaking up the combination of PWD and fire of pine forest.
Close relations existed between the pine forest fire and the epidemic spread of pine wilt disease(PWD).The adults of Monochamus alternatus emerged from the fire injury pine trees carried an average of 7 364 nemateodes,which will infect the healthy pines and causes the mortality of pine and epidemic spread of PWD.There are 3 types of PWD associated with the fire of pine forest,i.e.PWD occurs in the same year when forest is burned,PWD occurs in the next year after forest fire,and occurs several years later.It is an effective method for controlling PWD by clear-cutting all the fire dead pines parasitized by beetles and nematodes according to the results of studies.4 new methods can be used in the practice of breaking up the combination of PWD and fire of pine forest.
2000, 13(2): 188-191.
Abstract:
As called bamboo insect, Chilo fuscidentalis of Pyralidae usually hosts on bamboo of Gigantochloa.There is one generation every year.The larva emerge from Oct. to next Feb.There are rich protein,amino acid,fatty acid, micro-elements,vitamins and other nutritious elements in this milky white larva.The amount of protein is 30%～40%, the amount of amino acid is 29.90%, the amount of fat is 60.42%, the amount of unsaturated fatty acids is 55.9%.It is nutritious and delicious after being fried and fried deeply.As one kind of edible insect,the bamboo insect has good prospects of development and utilization because of it is nutritious.This insect resource is rich amount and easy to obtain.The host bamboo is rich in quantity and easy to culture.But in developing bamboo insect,it is necessary to protect this resource while using it.The resources of bamboo insect can be utilized properly only by the method of combining use with protection.
As called bamboo insect, Chilo fuscidentalis of Pyralidae usually hosts on bamboo of Gigantochloa.There is one generation every year.The larva emerge from Oct. to next Feb.There are rich protein,amino acid,fatty acid, micro-elements,vitamins and other nutritious elements in this milky white larva.The amount of protein is 30%～40%, the amount of amino acid is 29.90%, the amount of fat is 60.42%, the amount of unsaturated fatty acids is 55.9%.It is nutritious and delicious after being fried and fried deeply.As one kind of edible insect,the bamboo insect has good prospects of development and utilization because of it is nutritious.This insect resource is rich amount and easy to obtain.The host bamboo is rich in quantity and easy to culture.But in developing bamboo insect,it is necessary to protect this resource while using it.The resources of bamboo insect can be utilized properly only by the method of combining use with protection.
2000, 13(2): 192-196.
Abstract:
At the condition of 10～26 ℃,the development period of female generation corresponds to the accumulated temperature theorem.The threshold of development of female aphid is 3.6 ℃±1.1 ℃,the effective accumulated temperature is 358.7(d ℃).According to the parameters of biotemperature and theoretical equation,the development period of female generation can be predicted.The emergence period of fundatrigena can be controlled so as to correspond with the suitalbe phonological period of Rhus chinensis ,by means of regulation the storage temperature condition.It would achieve good result if the emergence period of fundatrigena corresponding to the phonological period of host tree,when the 3rd～8th leaves of Rhus chinensis is breaking successively.The ability endurance to starvation is very weak.Fundatrigena can only survival around 2 d.Therefore,the bags should be put up on to host tree without any delay at the beginning of the emergence period.
At the condition of 10～26 ℃,the development period of female generation corresponds to the accumulated temperature theorem.The threshold of development of female aphid is 3.6 ℃±1.1 ℃,the effective accumulated temperature is 358.7(d ℃).According to the parameters of biotemperature and theoretical equation,the development period of female generation can be predicted.The emergence period of fundatrigena can be controlled so as to correspond with the suitalbe phonological period of Rhus chinensis ,by means of regulation the storage temperature condition.It would achieve good result if the emergence period of fundatrigena corresponding to the phonological period of host tree,when the 3rd～8th leaves of Rhus chinensis is breaking successively.The ability endurance to starvation is very weak.Fundatrigena can only survival around 2 d.Therefore,the bags should be put up on to host tree without any delay at the beginning of the emergence period.
2000, 13(2): 197-202.
Abstract:
Agroforestry system or farm forestry is a production technique or method that combines agriculture and forestry to fully utilising the natural resources of sunlight,temperature and water.The investigation on the survey of the agroforestry systems microclimate in China since 1990′s was summarized.The characteristics of agroforestry systems microclimate are:(1)Component values of heat balance are positive in day time but negative at night.Among all component values of heat balance,the latent heat flux occupies the highest proportion from net radiation,both turbulence heat flux and soil heat flux occupy lower.(2)With the increase of plant coverage in agroforestry ecosystem,the net radiation,the relative intensity of illumination,temperature differentiation between day and night,and wind speed decrease,but air humidity increases.(3)With the increase of soil depth in the agroforestry ecosystem,the amplitude of temperature decreases in accordance with geometric series and the phase of temperature trailed in accordance with isogap series.The temperature gradience variation of soil are similar as the variety character of soil temperature.Knowledge on the characteristics of microclimate in the agroforestry systems is help ful for rational selecting plant coverage,tree height and canopy structure of trees in agroforestry systems.The study is favourable for maintaining the dynamic balance and increasing the comprehensive benefits of the systems.
Agroforestry system or farm forestry is a production technique or method that combines agriculture and forestry to fully utilising the natural resources of sunlight,temperature and water.The investigation on the survey of the agroforestry systems microclimate in China since 1990′s was summarized.The characteristics of agroforestry systems microclimate are:(1)Component values of heat balance are positive in day time but negative at night.Among all component values of heat balance,the latent heat flux occupies the highest proportion from net radiation,both turbulence heat flux and soil heat flux occupy lower.(2)With the increase of plant coverage in agroforestry ecosystem,the net radiation,the relative intensity of illumination,temperature differentiation between day and night,and wind speed decrease,but air humidity increases.(3)With the increase of soil depth in the agroforestry ecosystem,the amplitude of temperature decreases in accordance with geometric series and the phase of temperature trailed in accordance with isogap series.The temperature gradience variation of soil are similar as the variety character of soil temperature.Knowledge on the characteristics of microclimate in the agroforestry systems is help ful for rational selecting plant coverage,tree height and canopy structure of trees in agroforestry systems.The study is favourable for maintaining the dynamic balance and increasing the comprehensive benefits of the systems.
2000, 13(2): 203-208.
Abstract:
The trial of 21 eucalyptus species/provenances at the 4.5-year-old established at Kaiping City of Guangdong Province were analyzed.The results show that there are distinct differences on the increments of height,DBH and volume at the 4.5-year-old among 8 species with different provenances,and Eucalyptus urophylla is the best species among 8 species.Among 5 provenances of E. urophylla,Mandiri provenance(Seedlot No.17564)is the best provenance with a mean height,mean DBH,mean individual volume and volume increment of 13.44 m,11.45 cm,0.065 6 m 3 and 22.52 m3·hm-2 ·a-1 respectively,which are respectively 1.49,1.87,6.02 and 6.24 times compared with that of E.exserta as contrast. E. urophylla from Mandiri is suggested to be extended in this area and carry out the genetic improvement based on E. urophylla from Mandiri provenance.
The trial of 21 eucalyptus species/provenances at the 4.5-year-old established at Kaiping City of Guangdong Province were analyzed.The results show that there are distinct differences on the increments of height,DBH and volume at the 4.5-year-old among 8 species with different provenances,and Eucalyptus urophylla is the best species among 8 species.Among 5 provenances of E. urophylla,Mandiri provenance(Seedlot No.17564)is the best provenance with a mean height,mean DBH,mean individual volume and volume increment of 13.44 m,11.45 cm,0.065 6 m 3 and 22.52 m3·hm-2 ·a-1 respectively,which are respectively 1.49,1.87,6.02 and 6.24 times compared with that of E.exserta as contrast. E. urophylla from Mandiri is suggested to be extended in this area and carry out the genetic improvement based on E. urophylla from Mandiri provenance.
2000, 13(2): 209-212.
Abstract:
Ptilinus fuscus is distributed in 46 counties of 8 regions in Gansu Province.It seriously damages poplar.This insect has one generation every two years depending on elevation and climate.The adult emerges from May to July in Kangle County and from June to July in Weiyuan County.The larvae hibernate from October to March of next year,and damage trees from April to September,especially in April and May.The larva has 7 instars:the pupal period is from May to July.The emergence lasts 21 days on average continuously.Brushing the timber 3 times with mothproof liquid can poison the larva,and the controlling effects can reach 95%.Brushing the mothproof protective membrane can completely inhibit the adult insect from attack the timber.
Ptilinus fuscus is distributed in 46 counties of 8 regions in Gansu Province.It seriously damages poplar.This insect has one generation every two years depending on elevation and climate.The adult emerges from May to July in Kangle County and from June to July in Weiyuan County.The larvae hibernate from October to March of next year,and damage trees from April to September,especially in April and May.The larva has 7 instars:the pupal period is from May to July.The emergence lasts 21 days on average continuously.Brushing the timber 3 times with mothproof liquid can poison the larva,and the controlling effects can reach 95%.Brushing the mothproof protective membrane can completely inhibit the adult insect from attack the timber.
2000, 13(2): 213-216.
Abstract:
Different temperatures affect the effect of controlling pine caterpillars, Dendrolimus punctatus, by B.t pesticide apparently.While using B.t pesticide,the mortality of D. punctatus decreased as the temperature dropped.From the result of 4 temperature gradient tests,it was showed that 20 ℃ is the threshold that determine the effect of controlling D. punctatus by B.t. The results shows that different temperatures affect the feeding deterrence of the B.t to the D. punctatus larvae also,but in the all temperature treatments,the feeding deterrences are apparent consistently.
Different temperatures affect the effect of controlling pine caterpillars, Dendrolimus punctatus, by B.t pesticide apparently.While using B.t pesticide,the mortality of D. punctatus decreased as the temperature dropped.From the result of 4 temperature gradient tests,it was showed that 20 ℃ is the threshold that determine the effect of controlling D. punctatus by B.t. The results shows that different temperatures affect the feeding deterrence of the B.t to the D. punctatus larvae also,but in the all temperature treatments,the feeding deterrences are apparent consistently.
2000, 13(2): 217-221.
Abstract:
The stem of Ginkgo biloba were cultured on MS,modified MS and DCR basal medium,supplemented with various concentration of hormones—NAA,ZT(zeatin)and two types of nurture-CH(casein hydrolysate)and Ade(adenine). The aim was to study the effects of various basal medium,different hormones and nurtures on the growth and development of Ginkgo biloba stem. The result showed that the modified MS with CH 500 mg·L-1 was the best medium for inducing the development of axillary buds;the medium with NAA,ZT and Ade promoted axillary buds to be callus and inhibited them developing into shoots. The shoot rate was 89.3%. After cultured for 40 days,the clustered buds were emerged from axillary buds. The detached buds from clustered buds were cultured on modified MS basal medium or supplemented with CH 500 mg·L-1. The shoots grew well,and the reproduction coefficient was 3. The shoots from apical buds were also reproduced,and the reproduction coefficient was 4. The shoots were induced to root on MS+NAA 0.1 mg·L-1 medium,and the rooting rate was 33.3%.
The stem of Ginkgo biloba were cultured on MS,modified MS and DCR basal medium,supplemented with various concentration of hormones—NAA,ZT(zeatin)and two types of nurture-CH(casein hydrolysate)and Ade(adenine). The aim was to study the effects of various basal medium,different hormones and nurtures on the growth and development of Ginkgo biloba stem. The result showed that the modified MS with CH 500 mg·L-1 was the best medium for inducing the development of axillary buds;the medium with NAA,ZT and Ade promoted axillary buds to be callus and inhibited them developing into shoots. The shoot rate was 89.3%. After cultured for 40 days,the clustered buds were emerged from axillary buds. The detached buds from clustered buds were cultured on modified MS basal medium or supplemented with CH 500 mg·L-1. The shoots grew well,and the reproduction coefficient was 3. The shoots from apical buds were also reproduced,and the reproduction coefficient was 4. The shoots were induced to root on MS+NAA 0.1 mg·L-1 medium,and the rooting rate was 33.3%.
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