1993 Vol. 6, No. 6
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1993, 6(6): 597-602.
Abstract:
The drought resistance of Amorpha fruticosa L.,Hippophae ramnoides L.and Caragana microphylla Lam.in pots was investigated in three levels of soil water content.The growth indexes and the productivities of drought resistance (PDR) were measured.The effect of water stress on transpiration daily course and leaf water conservation ability was tested.The effect of water stress on osmoregulation and water content of the seedlings was obtained using Press Chamber and PV techniques.The results showed that C.microphylla had the strongest ability of drought resistance.Its capability of PDR,transpiration,water conservation and osomregulation was highest.The drought resistances of both H.rkamnoides and A.fruticosa were nearly the same.H.rhamnoides had a stronger capability of transpiration and water conservation regulation than that of A.fruticosa,but its osmoregulation ability was weaker than that of A.fruticosa.The PDR of them were similar to each other.
The drought resistance of Amorpha fruticosa L.,Hippophae ramnoides L.and Caragana microphylla Lam.in pots was investigated in three levels of soil water content.The growth indexes and the productivities of drought resistance (PDR) were measured.The effect of water stress on transpiration daily course and leaf water conservation ability was tested.The effect of water stress on osmoregulation and water content of the seedlings was obtained using Press Chamber and PV techniques.The results showed that C.microphylla had the strongest ability of drought resistance.Its capability of PDR,transpiration,water conservation and osomregulation was highest.The drought resistances of both H.rkamnoides and A.fruticosa were nearly the same.H.rhamnoides had a stronger capability of transpiration and water conservation regulation than that of A.fruticosa,but its osmoregulation ability was weaker than that of A.fruticosa.The PDR of them were similar to each other.
1993, 6(6): 603-608.
Abstract:
In view of the reality of the serious crisis of forest resources in China,the paper discusses how to rely on scientific and technological advances in alleviating the crisis of forest resources.The research topic,for the first time,raises a theory of structural readjustment to stimulate the need,which emphasizes the effect and the coordination of the elements of systematic structure of forest science/technology-resources,and the rational and effective disposition.It first gives a review of the actual strength,capabilities and potential of forest science and technology,and analyses the foundation of forest resources in terms of total quantity and quality of the forest resources.According to the character of long period of forest growth,it puts forward a concept of resource magnitude for commercial timber forest,and makes a quantitative estimate of the effect of technological advances in expanding forest resources.Finally,ten corresponding measures are proposed.
In view of the reality of the serious crisis of forest resources in China,the paper discusses how to rely on scientific and technological advances in alleviating the crisis of forest resources.The research topic,for the first time,raises a theory of structural readjustment to stimulate the need,which emphasizes the effect and the coordination of the elements of systematic structure of forest science/technology-resources,and the rational and effective disposition.It first gives a review of the actual strength,capabilities and potential of forest science and technology,and analyses the foundation of forest resources in terms of total quantity and quality of the forest resources.According to the character of long period of forest growth,it puts forward a concept of resource magnitude for commercial timber forest,and makes a quantitative estimate of the effect of technological advances in expanding forest resources.Finally,ten corresponding measures are proposed.
1993, 6(6): 609-617.
Abstract:
Fourty-eight species and six varieties of rattan belonging to 3 genera have been collected/introduced,in which,36 species and 5 varieties survived with a rate of 75.9%,among them,there are 30 species and 5 varieties of Calamus,5 species of Daemonorops and 1 species of Plectocomia.The results show that most of the native species have a stronger adaptability than the exotic ones collected.Most of the exotic species could not endure the low temperature and drought condition except for the species of Calamus dioicas,C.maniilensis,C.caesius and Daemonorops jenkinsiana.According to the growth performance of seedlings of different species,they could be incorporated into 3 types,viz.fast growing,sub-fast growing and slow growing,based on the bio-characteristics of flowering and fruiting,the species of rattan could be divided into 4 types,viz.long period of flowering development,short period of flowering development,long period of fruiting development and irregular period of flowering & fruiting.The species of C.tetrad actylus,D.margaritae,C.simplicifolius and C.dioicus are suitable for extending cultivaton in South China,and C.egregius,C.nambariensis var.xishuangbannanensis,C.distichus var.shangsiensis,D.jenkinsiana and C.caesius have a good potential for development in South China.
Fourty-eight species and six varieties of rattan belonging to 3 genera have been collected/introduced,in which,36 species and 5 varieties survived with a rate of 75.9%,among them,there are 30 species and 5 varieties of Calamus,5 species of Daemonorops and 1 species of Plectocomia.The results show that most of the native species have a stronger adaptability than the exotic ones collected.Most of the exotic species could not endure the low temperature and drought condition except for the species of Calamus dioicas,C.maniilensis,C.caesius and Daemonorops jenkinsiana.According to the growth performance of seedlings of different species,they could be incorporated into 3 types,viz.fast growing,sub-fast growing and slow growing,based on the bio-characteristics of flowering and fruiting,the species of rattan could be divided into 4 types,viz.long period of flowering development,short period of flowering development,long period of fruiting development and irregular period of flowering & fruiting.The species of C.tetrad actylus,D.margaritae,C.simplicifolius and C.dioicus are suitable for extending cultivaton in South China,and C.egregius,C.nambariensis var.xishuangbannanensis,C.distichus var.shangsiensis,D.jenkinsiana and C.caesius have a good potential for development in South China.
1993, 6(6): 618-620.
Abstract:
In the present paper two new species of sawflies are described and illustrated.The type specimens are deposited in the collection of the Research Institute of Forestry,the Chinese Academy of Forestry.1 Caliroa euodiae Xiao,new species (Fig.1)The new species is closely related to Caliroa floridana Smith,but differs from the latter in the black labrum,fore tibiae and fore tarsi;3rd antennal segment is about as long as 4th+5th antennal segments and is shoter than the apical four segments combined;anterior margin of clypeus is about straight;petiole of anal cell of hindwing is longer.Host plant;Evodia rutaecarpa (Juss.)Benth.Holotype♀,Nanchuan,Sichuan,1991 V,Zhang Shuying leg.Allo-type♂,same locality as holotype,1990,Tao Beiyin leg.Paratypes 4♀♀,3♂♂,same data as holotype.2 Rhainoceraea dioscoreae Xiao,new species (Fig.2)The new species is near Rhadinoceraea reitteri (Konow),but is distinct from the latter by the whitish labrum,clypeus and tibiae except for apex and by the head from above not expanded behind eyes.Host plant: Dioscorea opposita Thunb.;D.alata L.Holotype♀,Manning,Guangxi Zhang Aut.Reg.,1987.IV .22,Ji Hongxian leg.Allotype♂,same data as holotype.Paratypes 5♀♀,5♀♀,same data as holotype;5♀♀,4♂♂,Nanchuan,Sichuan,1985,Li Yongdai leg.
In the present paper two new species of sawflies are described and illustrated.The type specimens are deposited in the collection of the Research Institute of Forestry,the Chinese Academy of Forestry.1 Caliroa euodiae Xiao,new species (Fig.1)The new species is closely related to Caliroa floridana Smith,but differs from the latter in the black labrum,fore tibiae and fore tarsi;3rd antennal segment is about as long as 4th+5th antennal segments and is shoter than the apical four segments combined;anterior margin of clypeus is about straight;petiole of anal cell of hindwing is longer.Host plant;Evodia rutaecarpa (Juss.)Benth.Holotype♀,Nanchuan,Sichuan,1991 V,Zhang Shuying leg.Allo-type♂,same locality as holotype,1990,Tao Beiyin leg.Paratypes 4♀♀,3♂♂,same data as holotype.2 Rhainoceraea dioscoreae Xiao,new species (Fig.2)The new species is near Rhadinoceraea reitteri (Konow),but is distinct from the latter by the whitish labrum,clypeus and tibiae except for apex and by the head from above not expanded behind eyes.Host plant: Dioscorea opposita Thunb.;D.alata L.Holotype♀,Manning,Guangxi Zhang Aut.Reg.,1987.IV .22,Ji Hongxian leg.Allotype♂,same data as holotype.Paratypes 5♀♀,5♀♀,same data as holotype;5♀♀,4♂♂,Nanchuan,Sichuan,1985,Li Yongdai leg.
1993, 6(6): 621-626.
Abstract:
A total of 75 forest soil samples at 0~5cm depth collected from four nature reserves (Chang Bai Shan,Bai Hua Shan,Deng Hu Shan,Jiang Feng Ling) in China were examined for account of Bacillus and Bacillus thu-ringiensis,for description of the distribution of B.thuringiensis and calculation of the rate of B.thuringiensis to Bacillus in these forest soil.39 isolates of B.thuringiensis obtained from the forest soil were identified by means of the characterization of physiology-biochemistry and esterase type.It indicated that among the 39 isolates,17 belong to B.t.subsp.kurstaki (H-serotype 3a3b),6 belong to B.t.subsp.dendrolimus (H-serotype 4a4b),and 16 were different from known subspecies.These isolates were toxin-tested to insects.70% of the 39 isolates were Lepidopteran-toxin:the mortality against Clostera anachoreta and Dendrolimus punctatus were above 50%.Coleoptero-toxin were not observed.
A total of 75 forest soil samples at 0~5cm depth collected from four nature reserves (Chang Bai Shan,Bai Hua Shan,Deng Hu Shan,Jiang Feng Ling) in China were examined for account of Bacillus and Bacillus thu-ringiensis,for description of the distribution of B.thuringiensis and calculation of the rate of B.thuringiensis to Bacillus in these forest soil.39 isolates of B.thuringiensis obtained from the forest soil were identified by means of the characterization of physiology-biochemistry and esterase type.It indicated that among the 39 isolates,17 belong to B.t.subsp.kurstaki (H-serotype 3a3b),6 belong to B.t.subsp.dendrolimus (H-serotype 4a4b),and 16 were different from known subspecies.These isolates were toxin-tested to insects.70% of the 39 isolates were Lepidopteran-toxin:the mortality against Clostera anachoreta and Dendrolimus punctatus were above 50%.Coleoptero-toxin were not observed.
1993, 6(6): 627-632.
Abstract:
Age effect of the stock plants and the effect of the basal-cut shapes in cuttings of L.leptolepis on rooting ability were studied by using softwood cutting in the absence of growth hormones.Rooting rate was particular high (96.9%) for cuttings taken from 1.5-year-old stock plants.Better rooting rate were obtained when cuttings taken from 4.5 to 8.5 years old stock plants (72.1%~78.1%).Average number of root per cutting decreased significantly for cuttings taken from 8.5 years old stock plants when comparing with 1.5~4.5 year old plants.Rooting rate was negatively related with the age of stock plants (r=-0.9652*) and one-side rooting rate,however,was positive related with the age (r=0.999 3**) .Numder of roots per rooting cutting and maximum root length on average were not related with the age of stock plants.There was obvious difference in one-side rooting rate between different shapes of basal cut (F=12.336 2**),but no difference could be found for rooting rate.Adventitious roots developed only at the end (which has not been cut) of cuttings for one-side cut and V-shaped cut.Flat-cut at the base of cuttings reduced the one-side rooting rate which is helpful to improve the root quality of the rooting cuttings.
Age effect of the stock plants and the effect of the basal-cut shapes in cuttings of L.leptolepis on rooting ability were studied by using softwood cutting in the absence of growth hormones.Rooting rate was particular high (96.9%) for cuttings taken from 1.5-year-old stock plants.Better rooting rate were obtained when cuttings taken from 4.5 to 8.5 years old stock plants (72.1%~78.1%).Average number of root per cutting decreased significantly for cuttings taken from 8.5 years old stock plants when comparing with 1.5~4.5 year old plants.Rooting rate was negatively related with the age of stock plants (r=-0.9652*) and one-side rooting rate,however,was positive related with the age (r=0.999 3**) .Numder of roots per rooting cutting and maximum root length on average were not related with the age of stock plants.There was obvious difference in one-side rooting rate between different shapes of basal cut (F=12.336 2**),but no difference could be found for rooting rate.Adventitious roots developed only at the end (which has not been cut) of cuttings for one-side cut and V-shaped cut.Flat-cut at the base of cuttings reduced the one-side rooting rate which is helpful to improve the root quality of the rooting cuttings.
1993, 6(6): 633-642.
Abstract:
The initial research results of the project "impacts of climate change on productivity of forests in China" was presented in the present paper.In view of the relationship between productivity and environment,the characteristics of geographic distribution of primary productivity of forests in China were analyzed by comparison,and the relationship between stratal productivity,environmental conditions,species productivity and community structure were explored.The results showed net primary productivity,annual litterfall decreased gradually with the increase of latitude and altitude,whereas a reverse trend occurred in the standing crop of litter,which is heavily determined by temperature and precipitation regimes;there was no significant difference in the standing crop of biomass among various forest vegetations distributing in different physiographical zones,but mature natural forests with a complicated structure and high species diversity usually possessed a relatively larger amount of biomass;stratal productivity exhibited different variations in reciprocal exclusions or complements under different environmental conditions;species productivity varied with community structure,and it represented its role and position within a community,and therefore determined traits and nature of a community.
The initial research results of the project "impacts of climate change on productivity of forests in China" was presented in the present paper.In view of the relationship between productivity and environment,the characteristics of geographic distribution of primary productivity of forests in China were analyzed by comparison,and the relationship between stratal productivity,environmental conditions,species productivity and community structure were explored.The results showed net primary productivity,annual litterfall decreased gradually with the increase of latitude and altitude,whereas a reverse trend occurred in the standing crop of litter,which is heavily determined by temperature and precipitation regimes;there was no significant difference in the standing crop of biomass among various forest vegetations distributing in different physiographical zones,but mature natural forests with a complicated structure and high species diversity usually possessed a relatively larger amount of biomass;stratal productivity exhibited different variations in reciprocal exclusions or complements under different environmental conditions;species productivity varied with community structure,and it represented its role and position within a community,and therefore determined traits and nature of a community.
1993, 6(6): 643-649.
Abstract:
The productivity and nutrient cycling of 19-year-old Chinese fir plantations in different site conditions were studied in a small watershed located in Fenyi County,Jiangxi Province.The watershed was divided into three parts: rideg,slope and foot of a hill,for which soil physical and chemical properties were completely different.Significant differences in productivity and nutrient cycling were found under these site conditions.Main conclusion is as follows;1.The tree biomass in ridge,slope and foot,was 68.3374 t/ha,99.162 t/ha,141.1403 t/ha,respectively.The tree biomass at the ridge was 48.4% of that at the foot,and the average individual biomass of the ridge was only 14.95% of that at the foot.That means the ridge is not suitable for the growth of Chinese fir.2.The effect of site condition on growth begins from infant stage(1-4) and arrives the biggest in fast growing stage (5~12),then gradually declines.3.The amount and rate of element accumulation,return,absorption and cycling follow the order: ridge'sslope' sfoot's.And on any site conditions the cycling rate of N was always the highest and Mg the lowest.
The productivity and nutrient cycling of 19-year-old Chinese fir plantations in different site conditions were studied in a small watershed located in Fenyi County,Jiangxi Province.The watershed was divided into three parts: rideg,slope and foot of a hill,for which soil physical and chemical properties were completely different.Significant differences in productivity and nutrient cycling were found under these site conditions.Main conclusion is as follows;1.The tree biomass in ridge,slope and foot,was 68.3374 t/ha,99.162 t/ha,141.1403 t/ha,respectively.The tree biomass at the ridge was 48.4% of that at the foot,and the average individual biomass of the ridge was only 14.95% of that at the foot.That means the ridge is not suitable for the growth of Chinese fir.2.The effect of site condition on growth begins from infant stage(1-4) and arrives the biggest in fast growing stage (5~12),then gradually declines.3.The amount and rate of element accumulation,return,absorption and cycling follow the order: ridge'sslope' sfoot's.And on any site conditions the cycling rate of N was always the highest and Mg the lowest.
1993, 6(6): 650-653.
Abstract:
In 1986,milu (Elaphurus davidianus) herd was taken from five zoos in London,back to Dafeng Reserve within its historical distribution area for semi-free range.Data up to 1992 indicate the giving birth season and the moulting antler season for the herd take place 25 days and 22 days respectively prior to that in London.The seasonal distribution of milu biological rhythm at Dafeng Reserve is surprisingly identical to that at Woburn Abby in London when milu left their native habitat in the 90s of 19th century.This suggests that the milu herd has again adapted to the pho-toperiod of Dafeng Reserve and its biology-seasonal rhythm has been completely adjusted.The change of the giving birth season in the successive yearso-reveals the concrete process of adjustment.This artical compares the meteorological data of Woburn Abby,Nanhaizi Park & Dafeng Reserve,and discusses the adaptation of the species to climate.
In 1986,milu (Elaphurus davidianus) herd was taken from five zoos in London,back to Dafeng Reserve within its historical distribution area for semi-free range.Data up to 1992 indicate the giving birth season and the moulting antler season for the herd take place 25 days and 22 days respectively prior to that in London.The seasonal distribution of milu biological rhythm at Dafeng Reserve is surprisingly identical to that at Woburn Abby in London when milu left their native habitat in the 90s of 19th century.This suggests that the milu herd has again adapted to the pho-toperiod of Dafeng Reserve and its biology-seasonal rhythm has been completely adjusted.The change of the giving birth season in the successive yearso-reveals the concrete process of adjustment.This artical compares the meteorological data of Woburn Abby,Nanhaizi Park & Dafeng Reserve,and discusses the adaptation of the species to climate.
1993, 6(6): 654-660.
Abstract:
In field nursery,an experiment was carried out with a Fran-kia F287 strain and seedlings from 24 different seedlots of genotypes--14provenances of Casuarina equisetifolia and 10 C.junghuhniana.The results showed that there were significant differences (P0.05 or 0.01) among genotypes,and between inoculation and non-inoculation treatments in growth and biomass production.The increment mean values of 24 Frankia-genotype associations in nodule numbers,growth and biomass production of seedlings were also obviously fluctuating,root nodule numbers 0.3~8.9/plant;seedlings heights -2.1-40.3 cm;diameters at ground level -0.01~0.18 cm;biomass above ground (stem,shoot and leaf) -0.205~5.072 g/plant;biomass under ground (roots and nodules) -0.009~1.324 g/plant;total biomass -0.101~6.396 g/plant.This indicated that nitrogen fixation capabilities of different genotypes provenances and families of Casuarina species are genetically variable.Finally,by the Multiple Objective Strategic Decision Analysis methods,24 Frankia-genotype associations were optimized and ordered,and some optimum associations were found out.
In field nursery,an experiment was carried out with a Fran-kia F287 strain and seedlings from 24 different seedlots of genotypes--14provenances of Casuarina equisetifolia and 10 C.junghuhniana.The results showed that there were significant differences (P0.05 or 0.01) among genotypes,and between inoculation and non-inoculation treatments in growth and biomass production.The increment mean values of 24 Frankia-genotype associations in nodule numbers,growth and biomass production of seedlings were also obviously fluctuating,root nodule numbers 0.3~8.9/plant;seedlings heights -2.1-40.3 cm;diameters at ground level -0.01~0.18 cm;biomass above ground (stem,shoot and leaf) -0.205~5.072 g/plant;biomass under ground (roots and nodules) -0.009~1.324 g/plant;total biomass -0.101~6.396 g/plant.This indicated that nitrogen fixation capabilities of different genotypes provenances and families of Casuarina species are genetically variable.Finally,by the Multiple Objective Strategic Decision Analysis methods,24 Frankia-genotype associations were optimized and ordered,and some optimum associations were found out.
1993, 6(6): 661-665.
Abstract:
Cell suspension cultures of Acacia mearnsii De Wild maintained at 2℃,8 h/d light for 14 days had much more freezing tolerance,and its LT50 was lower from -3.4℃ to -8.2℃.Cold acclimation induced the increase of soluble protein content,and its time course of increase was in accordance with the development of freezing tolerance.Cycloheximide inhibited both the increase of soluble protein and the development of freezing tolerance.During cold acclimation,if cycloheximide was added at different time,the inhibition effects on development of freezing tolerance were different.These results indicated that development of freezing tolerance was nearing completion at about the tenth day of acclimation period.Exogenous sugar accelerated the time course of increase of soluble protein,however it was ineffective on the increase of final total content of soluble protein.Sugar wasn't a factor for the induction of freezing tolerance in cold acclimation of Acacia mearnsii.
Cell suspension cultures of Acacia mearnsii De Wild maintained at 2℃,8 h/d light for 14 days had much more freezing tolerance,and its LT50 was lower from -3.4℃ to -8.2℃.Cold acclimation induced the increase of soluble protein content,and its time course of increase was in accordance with the development of freezing tolerance.Cycloheximide inhibited both the increase of soluble protein and the development of freezing tolerance.During cold acclimation,if cycloheximide was added at different time,the inhibition effects on development of freezing tolerance were different.These results indicated that development of freezing tolerance was nearing completion at about the tenth day of acclimation period.Exogenous sugar accelerated the time course of increase of soluble protein,however it was ineffective on the increase of final total content of soluble protein.Sugar wasn't a factor for the induction of freezing tolerance in cold acclimation of Acacia mearnsii.
1993, 6(6): 666-671.
Abstract:
Gravitarmata margarotana Heinemann is one of the most important insect pests damaging shoots and cones of Pinus massoniana in China.The studies on its bioecology and control were carried out in Yuhang and Kaihua Counties,Zhejiang Province in 1985-1992.G.margarotana has one generation a year.Pupae overwinter in the soil.The habits of adult emergence and larval damage were observed.The relationship of insect occurrence to tree height,crown diameter,crown position and periodic biological phe-nomena are also narrated.Chemical pesticides could be used to control,the insect in masson pine seed orchard.The results showed that the spraying of 20% F'envalerate in mid-April is effective.
Gravitarmata margarotana Heinemann is one of the most important insect pests damaging shoots and cones of Pinus massoniana in China.The studies on its bioecology and control were carried out in Yuhang and Kaihua Counties,Zhejiang Province in 1985-1992.G.margarotana has one generation a year.Pupae overwinter in the soil.The habits of adult emergence and larval damage were observed.The relationship of insect occurrence to tree height,crown diameter,crown position and periodic biological phe-nomena are also narrated.Chemical pesticides could be used to control,the insect in masson pine seed orchard.The results showed that the spraying of 20% F'envalerate in mid-April is effective.
1993, 6(6): 672-679.
Abstract:
In this paper,the classification and research of stand growth models are stated from the view of the history of stand growth models.The relationship and application range of various types of stand growth models are evaluated.The principles of compactness and completeness of a model system are emphasized.Some problems which we should pay attention to in the establishment of stand growth models are pointed out.
In this paper,the classification and research of stand growth models are stated from the view of the history of stand growth models.The relationship and application range of various types of stand growth models are evaluated.The principles of compactness and completeness of a model system are emphasized.Some problems which we should pay attention to in the establishment of stand growth models are pointed out.
1993, 6(6): 680-685.
Abstract:
The paper deals with the biomass and production of principal secondary shrub in mangroves of Qingland harbour in Hainan Island.The community biomass of Limintzera racemosa,Ceriops tagal and Avicennia marina were measured by harvest method.The result shows that the biomass of these communities is 14.296,11.613 and 9.604t/ha,and their mean net production is 2.043,1.659 and 1.067 t/(ha.a),respectively.The biological productivity of the communities is respectively low,therefore,they should be transformed.In addition,the paper analyses the relation between biomass and leaf area index,and a transformation suggestion for each community is put forward.
The paper deals with the biomass and production of principal secondary shrub in mangroves of Qingland harbour in Hainan Island.The community biomass of Limintzera racemosa,Ceriops tagal and Avicennia marina were measured by harvest method.The result shows that the biomass of these communities is 14.296,11.613 and 9.604t/ha,and their mean net production is 2.043,1.659 and 1.067 t/(ha.a),respectively.The biological productivity of the communities is respectively low,therefore,they should be transformed.In addition,the paper analyses the relation between biomass and leaf area index,and a transformation suggestion for each community is put forward.
1993, 6(6): 686-690.
Abstract:
Three runoff plots were set up in the new forestation land of Chinese fir after control burning in Shaowu,Fujian province in 1992.The laws of changes in rain height,surface losses rate of soil and water were observed and studied.The results indicated that surface runoff and soil erosion on bare land is much more than those on new forestation land after control burning.Runoff coefficient of bare land is 3.8 times as that of the new forestation land.Surface runoff and surface soil losses lowered greatly after tending and earthing up of level terrace.Seasonal variations of surface runoff were mainly in fluenced by seasonal distribution of rainfall.The main reasons which caused serious surface runoff are heavy rains and rain storms.
Three runoff plots were set up in the new forestation land of Chinese fir after control burning in Shaowu,Fujian province in 1992.The laws of changes in rain height,surface losses rate of soil and water were observed and studied.The results indicated that surface runoff and soil erosion on bare land is much more than those on new forestation land after control burning.Runoff coefficient of bare land is 3.8 times as that of the new forestation land.Surface runoff and surface soil losses lowered greatly after tending and earthing up of level terrace.Seasonal variations of surface runoff were mainly in fluenced by seasonal distribution of rainfall.The main reasons which caused serious surface runoff are heavy rains and rain storms.
1993, 6(6): 691-698.
Abstract:
Typical investigation showed that for salinized soil on seashore,after more than 40 years' cultivation,the salt content have been reduced to0.1%,which is no longer harmful for the growth of common trees.However,the soils remain alkalescency,influencing the growth of some species of trees sensitive to alkali soil.Recently reclaimed coastal clayey salinized soil contains 0.5%~0.8% of salt,belonging to heavy salinized soil;and sand soil influenced by sea water contains 0.3%~0.4% of salt which are not harmful for the growth of Casuarina.For coastal sand soils,after a generation of Casuarina cultivation,the soil nutrients were depleted.Phosphours application significantly promoted the growth of Casuarina and enhenced the concentration of N,P,K and Mn in leaves.
Typical investigation showed that for salinized soil on seashore,after more than 40 years' cultivation,the salt content have been reduced to0.1%,which is no longer harmful for the growth of common trees.However,the soils remain alkalescency,influencing the growth of some species of trees sensitive to alkali soil.Recently reclaimed coastal clayey salinized soil contains 0.5%~0.8% of salt,belonging to heavy salinized soil;and sand soil influenced by sea water contains 0.3%~0.4% of salt which are not harmful for the growth of Casuarina.For coastal sand soils,after a generation of Casuarina cultivation,the soil nutrients were depleted.Phosphours application significantly promoted the growth of Casuarina and enhenced the concentration of N,P,K and Mn in leaves.
1993, 6(6): 699-702.
Abstract:
In this paper,for the error differentiation of applying neural network to recognize the unusual high temperature point by using NOAA data,on the base of KL transformation,the sample description is redefined for recognizing unusual high temperature problem with data supplied by the NOAA satellite.And the old Toptlogical structure of the network is modified.A new simulated experiment shows that the modified network is better than the old one in the recognizing precision.
In this paper,for the error differentiation of applying neural network to recognize the unusual high temperature point by using NOAA data,on the base of KL transformation,the sample description is redefined for recognizing unusual high temperature problem with data supplied by the NOAA satellite.And the old Toptlogical structure of the network is modified.A new simulated experiment shows that the modified network is better than the old one in the recognizing precision.
1993, 6(6): 702-702.
Abstract:
In this paper,the growth of the seedlings and young trees of Pinus massoniana are studied.The result indicates that the effectiveness of fertilization on the seedlings (are signicant.In this experiment,NO.3 (N1P3K3) is the best one with a under-ground biomass (dry weight) of 0.575 g/seedling,which is 21.6% more than that of the check(0.473 g/seedling).Over two years after planting,the height and root diameter of the young trees fertilized by N1P3K3 are 2.63m and 2.54cm respectively,but those of the young check trees only 2.13m and 2.01cm.There is a significant difference between them,and the analysis shows that there is a positive correlation between the height and root diameter of young trees and the underground biomass of the seedlings.
In this paper,the growth of the seedlings and young trees of Pinus massoniana are studied.The result indicates that the effectiveness of fertilization on the seedlings (are signicant.In this experiment,NO.3 (N1P3K3) is the best one with a under-ground biomass (dry weight) of 0.575 g/seedling,which is 21.6% more than that of the check(0.473 g/seedling).Over two years after planting,the height and root diameter of the young trees fertilized by N1P3K3 are 2.63m and 2.54cm respectively,but those of the young check trees only 2.13m and 2.01cm.There is a significant difference between them,and the analysis shows that there is a positive correlation between the height and root diameter of young trees and the underground biomass of the seedlings.
1993, 6(6): 703-706.
Abstract:
Anastatus albitarsis Ashmead is an important egg parasite for Dendrolimus punctatus Walker and is distributed in various types of pine forests in Zhejiang Province.There are two peaks of adult emergence in a year.May-June and September~October,which synchronize with the oviposition period of D.punctatus in Zhejiang province.Its parasitic rate is 22.9%.The body of the wasp is relatively big with a longer life-span and a powerful searching ability.Besides,it can be bred easily in large numbers with tussah eggs and is a useful parasite for control.
Anastatus albitarsis Ashmead is an important egg parasite for Dendrolimus punctatus Walker and is distributed in various types of pine forests in Zhejiang Province.There are two peaks of adult emergence in a year.May-June and September~October,which synchronize with the oviposition period of D.punctatus in Zhejiang province.Its parasitic rate is 22.9%.The body of the wasp is relatively big with a longer life-span and a powerful searching ability.Besides,it can be bred easily in large numbers with tussah eggs and is a useful parasite for control.
1993, 6(6): 707-710.
Abstract:
In this paper the influence on growth,nodulation and nitrogen fixing when applied N,P,K chemical fertilizers,organic fertilizer and ash fertilizer to M yrica rubra (Lour) Sieb et Zucc yourdling is studied.When adopting N,P,K three factors,five levels quadric rotation cut orthogonally desigh,three regression equations of N,P,K three factors to nodule growth increment,nodule nitrogen fixing activity,shoots and leaf growth increment of Myrica rubra arc obtained.The contrast test of application shows that the application of organic fertilizer and ash fertilizer promotes the growth,nodulation and nitrogen fixation of M yrica rubra.
In this paper the influence on growth,nodulation and nitrogen fixing when applied N,P,K chemical fertilizers,organic fertilizer and ash fertilizer to M yrica rubra (Lour) Sieb et Zucc yourdling is studied.When adopting N,P,K three factors,five levels quadric rotation cut orthogonally desigh,three regression equations of N,P,K three factors to nodule growth increment,nodule nitrogen fixing activity,shoots and leaf growth increment of Myrica rubra arc obtained.The contrast test of application shows that the application of organic fertilizer and ash fertilizer promotes the growth,nodulation and nitrogen fixation of M yrica rubra.
1993, 6(6): 711-713.
Abstract:
After many years' collection,the auther have obtained and identified 51 species of pathogens,which are now preserved in our institute,from 35 species of host plants of lac insects.Described in this paper are 11 species of saprophytic pathogenic fungi causing dark mildew on lac,26 species of parasitic pathogenic fungi on 12 species of host plants of lac insects and 1 hyperparasite (Ampelomyces quisqualis Ces ex Schlecht).18 species among these pathogens are new records in China.
After many years' collection,the auther have obtained and identified 51 species of pathogens,which are now preserved in our institute,from 35 species of host plants of lac insects.Described in this paper are 11 species of saprophytic pathogenic fungi causing dark mildew on lac,26 species of parasitic pathogenic fungi on 12 species of host plants of lac insects and 1 hyperparasite (Ampelomyces quisqualis Ces ex Schlecht).18 species among these pathogens are new records in China.
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