1999 Vol. 16, No. 4
Nine strains of Beauveria bassiana , collected from Lishui , Zhejiang , a natural epidemic area , were isolated during April to September .The test showed that three strains (B2 , B4 and B14) were the best on their mycelium growth , sporogenous ability and pathogenicity to masson-pine caterpillar , four strains (B7 , B10 , B11 , and B12)were the second best , and two strains (B6 and B13) were the worst .Consequently , B2 , B4 and B14 strains have applied-potentiality to control masson-pine caterpillar in future .
Investigation on Changle Forest Farm of Yuhang City , Zhejiang Province during 1982 ～ 1985 indicated that there were 13 families, 31 species of predatory enemies on M .matsumurae .Seven of them were reported at first which belong to ants and spiders.Ladybugs and ants were the most important predatory enemies in percentage, which contain 35 %～ 51 % and 30 %～35 % separately .Exochomus monglo , Sticholotis punctatus , Harmonia axyridis and Harmonia obscurosignata had a bigger population respectively .When the density of M .matsumutae increased , the number of ladybeetle increased , and in low density of M .matsumuae , the number of mite and pentatomid increased .When M .matsumurae and Cinara pinitabulaeformis developed in Pinus massoniana forests at same time , the number of ant , mite and pentatomid increased but ladybeetle and chrysopa decreased .
Rooting traits of cuttings from two , four , five , six and eight years old masson pine (Pinus massoniana) ortets in the same provenance were analysed after the cuttings were rooted in full exposure mist bed for three monthes .Except sum of the branch roots and the diameter of the longest root , the cyclophysis was found in time for callusing and rooting , sum of the adventitious roots , length of the longest root , total length of the roots and root rate , especially in eight years old ortet .Root effective index of cuttings from two years old ortets was heighest (0.646) , and that from eight years old ones was the lowest (0.056) .However , variation of cuttings from two and four years old ortets was not notable . Therefore , using the seedlings of the half-sib or full-sib families as the masson pine ortets was proposed . In order to solve the probleme of cyclophysis , cuttings from stecklings and seedlings were compared .As a result , the root rate and root effective index from stecklings were eighty percent and 0.451 respectively , higher than those from seedlings sixty-five percent and 0.195 .And , other root traits of cuttings from stecklings were better than those from seedlings indicated that serial cutting rooting could rejuvenate the masson pine ortets .
For increasing sampling and decreasing poplar borer harming of protective belt along the Changjiang River , Multi-clone admixture planting of poplar was studied in Anhui Province .The results showed that compared with one-clone planting , sampling and profit rate of multi-clone admixture planting of poplar were increased over 15 %, and trees harmed by stem borers were controled less 3 %.Four fine colones which sampling were over 18.4 %～ 47.5 % compared with Ⅰ-69 were selected (cv .Zhonglin- 490 , cv .Zhonglin-487 , cv .Zhonglin-715 , and cv .Zhonglin-789).Growth steges and grades of tested poplars were divided .
The study was made in Lin,an City of Zhejiang Province .The test seed of Camptotheca acuminata was from 10 provinces of China .Among of them , Kunming provenance gave excellent seed quality :pureness (89.3 %), thousand grain weight (71.26 g ), germination percent (94 %), germinating energy (83 %)and mean germination speed (7.2 d).The fast-growing stage was in the middle June , and the peak value appeared in September .Height increment of yearling fall excellently into Nanjing provenance (133.97 cm), Pingnan provenance (133.97 cm)and Lishui provenance (132.18 cm).
Growth and fruiting of more than 20 varieties belonging to 8 types of commercial trees cultivated under normal conditions in the hilly regions of middle part of Zhejiang Province and changes of soil chemical characteristics have been discussed .The practice shows that such evergreen species as Citrus reticulata cv .Ponkan , C .changshan-huyou , Chinese strawberry and C .unshiu are most suitable for this region with such soil ;such pomeloes as Yongjia fragrant pomelo and gaoxie pomelo and such navel oranges as C .sinensis cv .Skaggs Bonanza and Newhall Navel Orange can be planted because of their good performance in growth and fruiting ;chestnut among deciduous species is most suitable , too ;Tianmu sweet plum can also be planted so long as pollinating varieties are properly mixed;capable of fruiting , ginkgo grows well and dogwood grows vigorously late in growth ;sweet varieties among persimmons have a heavy flower drop and fruit drop , which results in a low yield while puckery varieties fruit very well ;Pujiang peachshaped plum and Fujian nai plum only flower with no fruits or fruits heavily damaged by insects ;and jujube is not suitable for planting on account of poor growth and fruits of poor quality .Plowed and occupied by trees , soil has changed in chemical characteristics under the influence of commercial species of trees planted and the application of fertilizers to the soil , favorable to growth and fruiting of the trees .All this can be seen from the reduction of soil acidity and increase in both soil fertility and land production potential .With a good ecological and economic effect , C .changshan-huyou , C .unshiu , Chines strawberry , etc .can tolerate poor soil , showing a high suitability and a high and stable yield .
In foreign soil seedbeds , urea (N), calcium superphosphate (P), potassium chloride (K) and decayed cake manure (M)were applicated for 2 weeks before planting Chinese fir year-seedling in March .Application rate was as follows :A plot , check ;B , N 50.0 gm -2 , P 45.0 gm -2 , K 30.0 gm -2 ;C , M 600.0 gm -2 ;D , N 25.0 gm -2 , P 22.5 gm -2 , K 15.0 gm -2 , M 300.0 gm -2 ;E , M 600.0 gm -2 , N 50.0 gm -2 , P 45.0 gm -2 , and K 30.0 gm -2 .The results of analysis in September indicated that fertilization was of great value for improving biomass , root vigor and chlorophyll content of Chinese fir seedling .In comparison with A , biomass , root vigor and chlorophyll content of seedling in B , C and D were 2.05 , 1.60 , 2.11 times , 1.24 , 1.75 , 1.44 times , and 1.35 , 1.40 , 1.52 times, respectively .E was of great effect for improving physiological function of seedling .Fertilization increased not only land capability , but also available nutrient of soil.
Effect of intercorpping green manure crops on water and soil losses , soil fertility and tree growth are studied through runoff plots due to serious soil erosion after control burning .The results are as follows:intercropping different green manure crops can control soil erosion , improve soil physical properties and nutrients conditions , and enhance tree growth of Chinese fir .The soil erosion of intercropping land has decreased by 17.76 % ～ 52.25 % compared with that of control burning land . Therefore , intercorpping green manure crops after control burning is a practical technique in the south of China .
The results from the experiments of rare earth elements applied to forest trees show that in proper condition , rare earth elements treatments have position effects on physiological characteristics of forest trees .Rare earth elements can markedly increase the growth and yield of forest trees , improve the level of metabolism and the ability of resistance to improper environment of forest trees and so on .The effects of rare earth elements on forest trees may be related to the regulations of contents and activities in enzyme and endogenous hormones .More study is necessary for the physiological mechanism of rare earth elements to the forestry.
Studies on water and soil conservation effectiveness of different types of vegetation on the subtropical rocky coast showed that surface ranoff and erosion modulus in the different types of vegetation consisted of young trees decreased by 9.05 % and 39.29 %, respectively , compared with those of the controls, and their soil moisture content was 17.94 % higher than that of the controls .Soil moisture content had close relation with the physical properties of soil besides vegetation type .The main physical factor of soil affecting soil moisture content was unit weight of soil , and ratio noncapillary porosity to total porosity were secondary .The main meteorological factors affecting soil moisture content were air temperature and preciptation .The effect of physical properties of soil on surface runoff was greater than that on erosion modulus .
Contents of magnolol and honokiol in 70 samples collected from the main growing areas of Magnolia officinalis within the country were analyzed by means of HPLC .The results show that there is a significant correlation between the appearance characteristics of bark and its internal quality .The bark which is thick , rough in appearance , oily , dark in powder color and small in fiber content is of high quality and vice versa .Powder color and bark thickness are main parameters in appearance , which are most important in establishing a quality standard for M .officinalis and simple and operationable in making a judgement of quality in the course of genetic breeding .
Based on the study of harvested fruits of oil camellia in production experiments and laboratory , a new processing technology was developed .The results showed that the rate of oil content in the fruits decreased in the course of stacking .Comparing with the old technology , the new technology could increase the oil-yielding rate by 12 % and the processing cost only increased 3.0 Yuant-1 .It could be operated and popularized in production easily .
Physical and mechanical properties of Castanopsis kawakamii wood from plantation and natural forest are determined and analyzed comparatively .The results show that the density , shrinkage , compression strength parallel to grain , the bending strength and hardness of cross section of Castanopsiskawakamii wood from plantation and natural forest all belong to middle level .The other indexes of Castanopsis kawakamii wood from plantation are slightly bigger than that from natural forest expect that elastic modulus of bending , impact toughness and resistance to cleavage from plantation are less than that from natural forest .Different significant t test show that there are significant differences on elastic modulus of bending , impact toughness and resistance to cleavage but no ones on the other indexes between plantation and natural forest .The conclusions provide scientific basis for plantation cultivation of Castanopsis kawakamii .
The characteristics of roof top garden and its construction are studied by taking an example of design and working for roof top garden of Xiaoshan International Hotel .Roof top garden is small in area , and separate between planting soil and natural soil .In design and construction , roof top loading , waterproofing and drainage etc .are restrict factors .Therefore , the engineer should follow safe , beautiful and economic laws , combine ecological environment , technique of garden-making , architectural structure and garden plants with design , carry out modern roof top garden with local conditions .
The premiss of proper usage of agriculture land is to set up the relationship between the property of land and the most suitable plant , land suitability evaluation .The article discusses the measurement system of land evaluation and the main process of soil evaluation based GIS .A model of fuzzy evaluation is given also .The experiment proved the method of evaluation based GIS and fuzzy is suitable.
Ten full-length research papers are selected from 10 overseas scientific periodicals related to forestry science .The analysis of thematic patterns and distribution shows that the two common patterns in forestry literature are marked theme and unmarked theme representing 52.7 % and 44.1 % respectively . In Introduction and Results and Discussion no striking difference is found in the percentage of the above two themes .Marked theme is frequently used in Experiment section , where passivization , one kind of marked themes , occurs in a higher frequency than in the section of Results and Discussion , while other forms of marked themes demonstrate an opposite tendency .
Based on the investigation into the type and number of specialized periodicals in agriculture , forestry , biology and environmental science ordered by various forestry units , and into the number of forestry disc data base and the network of computers possessed by various units , this paper statistically analyzes the store and usage of specialized periodicals in Zhejiang forestry and the application of computer message index , and discovers that in Zhejiang forestry , the periodicals in forestry are the major collected information .College and research institutes constitute the majority of the collected periodicals .On the basis of the findings , it puts forward some proposals on making good use of available forestry information resources and on their proper development .
Based on the statistical data of 74 cities in Zhejiang Province in 1996 , the paper evaluated the national economic status by using the principal component analysis .The principal factor reflecting the economic condition of the cities was the process of industrialization and the following was the construction of the modernization of agriculture .The 74 cities were divided into 5 types by using the cluster analysis . They were midindustrialization cities, fishery cities in islands , rich cities in suburbs , cities with enough to eat and wear and poverty cities in mountain areas .The results could give a scientific guides for further economic development in these areas .
Applying logical flow chart to the discussion of causes of pine wilt disease infecting healthy pine forest , integrating with artificial provocation experiments in the new epidemic spots of pine wilt disease in Ningbo City of Zhejiang Province , and coming to the conclusion that man-caused dissemination, fire induction , non-control and natural dissemination are four causes leading new epidemic spots .Among which wind is a key factor that is advantageous to the diffusion of Monochamus alternatus .Healthy pine forests are infected by pine wilt disease in the east part of Beilun District where is a long way from the infected pine forests over 4.5 km .
Private individuals and companies own 45 % of California's productive forestland . To harvest timber , these owners are required to have a licensed professional forester prepare detailed management plan that goes through extensive review by the state .Plans cost ＄6 000 ～ ＄12 000 and up , and may 6 or more months to prepare and go through review by the state .Forester'sdecisions are constrained by laws , stand conditions , economics , and the landowner's objectives .The Forest Practice Rules have detailed standards for selecting silvicultural systems and meeting post-harvest stocking .Factors considered in project feasibility include costs of plan preparation , tree marking , logging , administration , trucking , taxes , planting , and presence of any protected species .On many properties under 16 hectares, these costs exceed the revenues that can be generated from the standing timber . Important issues for California's forest landowners include an increasingly tight regulatory climate , high inheritance taxes , and extreme fire danger resulting from fire suppression .As the public demands aesthetically pleasing forests as well as forest products , California is faced with importing much of its wood products supply .Within the framework of existing laws , foresters balance ecology , economy , and public opinion to provide for the diverse values of California's populations .Table 2 References2
Taiwania flousiana and T .cryptomerioides are endemic rare tree species naturaly ranged in China .In 1992 ～ 1993 , introduction and forestation of Taiwania were made in Suichang County of Zhejiang Province .The results showed that these two tree species had a character of fast-growing , with a good adaptability to climatic condition and soil site .At 6-year-old , average tree height and ground diameter of Taiwania flousiana reached 3.61 m and 8.4 cm .And at 5-year-old , average tree height and ground diamater of T .cryptomerioides were 2.54 m and 5.0 cm .These two species rivaled fast-growing and high-yield tree species of Cunninghamia lanceolata in growth speed .Tree introduction of Taiwania to Suichang achieves first success .