1995 Vol. 12, No. 3
The leaves, petioles and nodes of 9 species of Calyeanthaceae were dissected. The 9 species all have two lateraltraces and one gape. The leaf structure shows slightly different. The lateral bundles in petiole show that the family can be devided into two genus: Calycanthus which has 3~6 lateral bundles; and Chimonanthus which has 2 lateral bundles. Based on the oil cell in leaf the Chimonanthus can be separated naturally into two groups: one has non-oil cell, such as Ch. praecox and Ch. campanulatus, the other has oil cells, such asCh. salicilolius, Ch. zheiiangensis, Ch. nitens and Ch. grammatus. It can not give qaulitative inforamtion to differ aomng the four species.
There is higher content of total-P, organic-P and availabe-P in the rhizosphere soil of Chinese sassafras than that of Chinese fir. Between the rhizosphere soils of the two kinds trees, there is no significant difference in mount of mineral phosphorus but is significant difference in its constituent, which can be explained by much more content of occluded-P (acounted to 61.48% of mineral phosphorus) in Chinese fir rhizosphere soil than that (acounted to 39.69%) in Chinese sassafras, and by much more content of Fe-P and Ca -P in Chinese sassafas rhizosphere soil than that in Chinese fir. In two rhizosphere soils, the qauntity of available-P is largely correlated with contents of AI-P and Ca-P, while there is lower content of AI-P.
Data of Lei bamboo rhizome obtained from 50 plots showed that the buds on rhizome of Lei bamoo had 3 distribution laws: (1)horizontal distribution half of living buds and died buds; (2) vertical distribution of buds; and (3) age distribution of buds. The yield of bamboo sprout was closely related to the amount of buds on the rhizomes with 2-year-old and in the soil layer of 21 to 30 cm, which showed that bamboo sprout mainly shooted on the rhizome and in the soil layer. Ground cover thickness on the stands had a significant influence on the numbers of shooted buds and died buds. The ground cover technique prolonged the differentation of buds and the emergence of Lei bamboo sprouts.
Green biomass and leaf area of Masson pine, broad leaved shrub and herb were measured in the young Masson pine forests in Jiangshan City and Quxiano County, Zhejiang Province in 1994. The regression equations between the shade density and the green biomass of arbor layer, bush layer and field layer were established; and the leaf area indexes of the forests were given.
Low yielding forest of Pinus eliottii and Pinus massoniana mixed with Fokienia hodginsii in Lishui Prefecture, Zhejiang Province, suggested that the volume of mixed forest of pine and cypress was increased by 111% hm-2 than that of pure forest. Fokienia hodginsii had a strong force of nature regeneration in the mixed forest, with fast-growing and easy-Planting. The mixed forest can form a good stand structure, and is an ideal stand improvement type of low yielding pine forest.
Compared with those in oak stand, the interception of the brush and litter layer in cutting blank increased to varying degrees as well as the coeffieients of surface runoff and subsurface runoff. There oppeared an earlier occurance of surface runoff and a lower infiltration rate in period of storms. The surface runoff carried away 43.14% of nutrients inputted by rainfall in oak stand and 41.95% in cutting blank.
The pathogenic fungi, Vladracula annuliformis (Sydow et Butler) P. Cannon, Minter et Kamal, is ascertained in the light of the ascoamta and asexaul spore. Its distribution limit and ecological characteristics are recorded.
Through measurement of the leaf qauntity damaged by Eutomostethus deqingensis and the leaf area of phyllostachys pubecens stand in Deqing County, Zhejiang Province, and measurement of culm quantity on the sample plots damaged by E. deqingensis and calculation of the controlling costs and value of the young culms on the sample plots, the economic thresholds for the larvae were ascertained.
On the young bamboo, the contents of holocellulose, pentosan, 1% NaOH extractive, etc. were relatively high, those of lignin, ash, espectively silica relatively low. On the one to two year old bamboo, the contents of ash and silica had a significant difference, and those of 1% NaOH extractive and the other chemical elements hadnt. On the over two year old bamboo, the contents of ash and silica was greatly increased at the bamboo bole above, but be did at the bamboo bole middle-below after 4 years old.
The site fertility decline of planted forests has been brought to the forest scientists' close attentions on a globle scale. This paper summarizes the present situations of site fertility decline of the planted forests at home and abroad, analyses mainly the causes of site fertility decline for the pure coniferous planted forests in Fujian, and advances a series of counter measures to preserve soil fertility and achieve sustainable development for the planted forests.
Town, in the course of modernization of mountain area, is a major carrier and traction force. It is very important to mountain area development in economy and society. The system structure, cultural feature, current situation and growth mechanism of Linan mountain towns are analysed, and the development goal of the towns in future and the ways to deal with the goal are made from sociology.
Investigating Scientia Silvae Sinicae and Forestry Science published in 1993, analyzing the subject structure, time coverage, number and type of the citations, the authors worked to declare the similarities and differences of China and America in forest research. Both forest scientists hadn't done enough in continous scientific research, which was a key obstacle to develop in depth for forest research.
This paper is an attempt to present a comprehensive picture of Communicative Competence often misleadingly judged by some language teachers, and further discusses the tasks of ESL classroom teaching, strategies and significance to promote this competence. The paper holds that the clarification of the confusion is vital to the attainment of the ultimate goal in the teaching of ESL.
Investigation of two F1 seed orchards of Chinese fir at Changle Forest Farm and Qingyuan Forest Farm in Zhejiang Province and determination of carbob-nitrogen ratio of same clone in different canopy densities showed that the effect of canopy density on seed yield had been great, with lower yield per crown in too scarce or too dense canopy densities. In full cone period, the seed orchard should be timely thinned to ensure the best suitable canopy densities (from 0.58 to 0.66).
The methods for appraising forest tree and forest land of timber forest resources were discussed under Chinese forestry condition, with the example of Chinese fir working section in Baimashan Forest Farm of Shuichang, Zhejiang. Some problems demanding prompt solution were aIso suggested.
Foresty vegetable resources in Fuyang fall into 4 types and over 120 species. Scientific developing and utilization of forest vegetable resourcesthatis mainly in order to enrich residents` food of town and conutry, and promote economy increment in mountain area.
Chinese chestnut fruit was damaged byDichocrocis punctiferalis in Zhuji City of Zhejiang Province with 29% of injury. Control could be made at the Iarval stage in the second ten days of August by brushing trunk with 3-fold solution of omethoate 40EC, resulting in more than 76.5% of the larvae being killed, and the seeds being increased by 77.5kg per hectare. The control cost avaraged 34.8 yuan RMB per hectare.
Control of Cnidocamp flavescens was made at the larval stage by injecting omethoate 40EC into the holes bored in the trunk of Platanus orientalis, resulting in more than 83.9% of the larvae being killed, having a dead peak of the Iarvae in the fourth day to the sixth day after injection.
The contact toxicities of azadirachtin, dimilinⅢ and deltamethrin were tested, and the LD50 were 2.5990, 1.7500 and 0.0012g per larva, respectively. Bioassay results showed that azadirachtin, toosendanin and dimilinⅢ had potent toxicity as insect growth regulators to the larvae in laboratory. Azadiraehtin and dimilinⅢ, with a concentration of 200mg/kg, could kill the eggs of Masson-pine caterpillar moths with one, four and seven ages in days, and their adjusted mortality rate could reach by 76.6% and 90.0%, respectively. The symptoms of the pest after applying insecticides were observed in the test.