• 中国中文核心期刊
  • 中国科学引文数据库(CSCD)核心库来源期刊
  • 中国科技论文统计源期刊(CJCR)
  • 第二届国家期刊奖提名奖

2005 Vol. 18, No. 4

Display Method:
Study on the Taxol Content in Taxus yunnanensis of Different Age and Different Provenance
SU Jian-rong, ZHANG Zhi-jun, DENG Jiang
2005, 18(4): 369-374.
Abstract:
Contents of taxol in barks,3 years old shoots and 1 year old needles of Taxus yunnanensis of 10 ages and 12 provenances were analyzed by HPLC.The average contents of taxol in the barks,3 years old shoot and 1 year old needles were 0.004 8%,0.004 0% and 0.015 1% respectively.The contents of taxol in barks had a significantly correlation with age.The contens of taxol in 3 years old shoot and 1 year old needles of the plant had no significant correlation with age.In 12 different Taxus yunnanensis provenances,the contents of taxol in 1 year old needles from Xinping,Linlang and Lushui provenances were higher;the contents of taxol in 3 years old shoot from Langping,Linlang and Xinping provenances were higher;the contents of taxol in barks from Jingdong,Muli and Linlang provenances were higher.It was found that temperature,nutrition and sunshine were the most important among six essential factors affecting the content of taxol.
A Study on Estimation of Vegetation Fraction by Using QuickBird Imagery
CHEN Qiao, CHEN Yong-fu
2005, 18(4): 375-380.
Abstract:
Using 3-bands method, NDVI method for dimidiate pixel model and integration method by QuickBird image to estimate the vegetation fraction of study area, and the estimating values of the three methods were compared and validated. The results were as follows: all the relativities of the three method were high between the estimating values and the actual values (they were all more than 0.84), and the average relative error of NDVI method for dimidiate pixel model and integration method were not high and the average estimated accuracy of all land cover type of NDVI method for dimidiate pixel model and integration method was more than 92% in the study area. The result of systematic nature validation suggested that the estimating precision of NDVI method for dimidiate pixel model and integration method was relatively high, and they had good unitary nature, so they both could be used in estimating of vegetation fraction from QuickBird image data.
Hybrids Breeding of Seabuckthorn for Multipurpose Use
ZHANG Jian-guo, HUANG Quan, LUO Hong-mei
2005, 18(4): 381-386.
Abstract:
In order to improve seabuckthorn for both fruit production and for use in soil erosion control, Chinese Seabuckthorn (H.rhamnoides ssp.Sinensis) as male parent was crossed with Russian and Mongolian Seabuckthorn(H.rhamnoides ssp. Mongolica) as female parent. The Russian and Mongolian cultivars have large fruits and few or nearly no thorn, and were originated from the selection made in the Altai region. Cross pollination was started in 1996. Five hybrid individual tree were selected in 2003 , of which 3 individuals(C1,C2,C3) were from the crosses of Chinese(♂) to Russian(♀) cultivars and 2 (C 13,C 16) from crosses of Chinese(♂) to Mongolian(♀) cultivars. Experimental results indicated that the selected 5 hybrids were significantly larger than the female parents in height, ground diameter and crown width ,but close to the male parents.The number of thorns in 2-year-old branches of the hybrids was 2~3, fall between the numbers of thorns in male and female parents ,but a 85%reduction compared to Chinese cultivars. The 100-berry-weight of hybrids was 21.98~29.98 g,significantly smaller than that of the female parents, but 9.6%~48.8% larger than that of the Chinese cultivars. The results showed that the hybrids were intermediate in most characters compared with their parents. It also indicated significant correlation of 100-berry-weight with berry length and length/width ratio and weak correlation with berry width.It is obvious that fruit size is mainly determined by berry length. 1 000-seed-weight was significantly correlated with thickness, length and width of seeds, but not significantly correlated with length/width ratio.
Studies on Container Seedlings Cultural Techniques of Three Native Broad-leaved Tree Species
JIN Guo-qing, ZHOU Zhi-chun, HU Hong-bao, YU Lin, WANG Yue-sheng, HONG Gui-mu
2005, 18(4): 387-392.
Abstract:
This paper dealt with the studies on how the media mixture and the containers size affect seedling quality of three native broad-leaved species of Cinnamomum camphora, Manglietia yuyuanensis and Liriodendron chinense. The results indicated that media type and mixture produced a great impact on the growth of container seedlings of various species. There was great interaction between species and media. The container seedlings in the media of peat as main material grew more quickly. However, the container seedlings in the media of sawdust as main material grew more slowly. The pure peat has many advantages, but it should not be used widely in production because of higher price and unfavorable effect of saturated water content on the root growth after watering. The test showed that the best medium mixture ratio of peat, burnt-soil, yellow soil and calcium magnesium phosphate was 39∶40∶20∶1. If sawdust is used as medium, the sawdust mixture ratio of medium should be reduced and controlled below 20%. To counter biological characteristics of tree species and applicable medium mixture, the size of container seedlings should be made in order to achieve afforestation in the rainy season in the south of Yangtze River area. The studies showed that the fistular container seedlings may be adopted, but the prior condition is to make sure afforestation in rainy season in time, or the bigger size of cuppy container should be used.
Grain Yield and Adaptability of Cajanus cajan New Varieties
LI Zheng-hong, ZHOU Chao-hong, GU Yong, LIU Fu-tai, HE Jin-fu, LI Fu-qiang
2005, 18(4): 393-397.
Abstract:
9 new varieties of Cajanus cajan were tested at Yuanjiang County,Lushui County and Yunxian County,Yunnan province,with a local variety as CK.The grain yield and adaptability of the varieties were analyzed.V7,V5 and V6 were the most desirable varieties for their good stability,low variation and obviously higher seed yield than the CK.V 10,V3,and V2 produced higher grain yield and higher variation than that of the CK,their release should be on suitable environment.The grain yield of V8,V1,and V9 were lower than that of the CK,but V1 and V9 had the best qualities such as big pods and seeds,as well as their green seeds were sweeter than pea,so V1 and V9 could also be released in thir suited districts.The analysis on the domino effect of site showed the ideal environment like Lushui for pigeonpea cultivation.
Study on Urban Forest Community Models of Shaoxing City
SHI Jiu-xi, WANG Xiao-ming, QUE Guo-ning, CHEN Xiu-long, SHEN Wu-shan, HUANG Yue-fu
2005, 18(4): 398-405.
Abstract:
This paper dealt with the evaluation on the quality and benefit of the existing urban forest communities of Shaoxing City, Zhejiang Province,based on established indicator framework focusing on city forest three-dimension biomass and mean healthy level,14 main models assembled with local phytobiocenose were selected, which have been extended in diversity according to the assemble principle of same species, or similar species with similar characteristics, on the basis of knowledge that the communities structure is fixed by ecological and biological characteristics of the trees. As a result of that, the different urban forest community models, suited in different land type, has been identified in typical city like Shaoxing city.
Plant Species Diversity of Natural Secondary Forest Community in Northwest Zhejiang
ZHOU Ben-zhi, FU Mao-yi, LI Zheng-cai, XIE Jin-zhong, Manuel Ruiz Perez, Brian Belcher, YANG Xiao-sheng, WU Ming
2005, 18(4): 406-411.
Abstract:
The characteristics of the plant species diversity of natural secondary forest community in the northwest Zhejiang Province were studied. The plant growth form and the importance value of the community were determined, and the richness, evenness, and species diversity index of each layer of the community were calculated with varied calculation method. The results are as follows: (1) There existed the comparatively obvious dominant species within each layer of the natural secondary forest community, with Cyclobalanopsis glauca in tree layer, Cyclobalanopsis glauca and Loropetalum chinese in shrub layer and Indocalamus tessellatus in herb layer as the dominant species. (2) The natural secondary forest community in this area had rich plant species, with the species number of arbor tree being the most and that of the herb being the least. In terms of the layer of the natural secondary forest, the herb layer had the highest richness, followed by shrub layer and tree layer with a similar richness between them. The shrub layer had the highest evenness, followed by tree layer. While the richness of the herb layer was the lowest. Also, the shrub layer had the highest species diversity index calculated with various methods. The index for herb layer was the lowest even if it had the highest richness. (3) There were higher plant species diversity index and higher quantity index in the forest community which was closed for a longer time and suffered from less human disturbance.
Analysis of Aroma Constituents of Camellia Variety Kramer's Supreme
FAN Zheng-qi, LI Ji-yuan, TIAN Min, LI Xin-lei
2005, 18(4): 412-415.
Abstract:
The essential oil from Kramer's supreme was analyzed by GC/MS method. 37compounds were identified, which occupied 54.84% in the total essential oil, and they belonged to alcohol, alkenonic/alcoholic oxide, aldehyde, ester, alkene, acid, alkyl,and Phenanthrene. Alcohol is on the top of the compounds list. The characteristic constituents of aroma are Linalool, cis-Linaloloxide II, Methyl Salicylate, 3,7-dimethyl-(+-)-1,6-Octadien-3-ol, alpha-Terpineol, Nonanal, Tetracosane. The Linalool was found to be 39.97% in the total essential oil.
Studies on Regularity of Accumulation and Disappearance of Starch Grains in Microsporogenesis and Malegametogenesis of Keteleeria fortunei
LI Guo-ping, HUANG Qun-ce, QIN Guang-yong
2005, 18(4): 416-420.
Abstract:
The paper dealt with detailed studies on regularity of accumulation and disappearance of starch grains in microsporogenesis,pollen development and pollen germination of Keteleeria fortunei (Murr.) Carr.. The microspore mother cells (MMC) were formed in late January,2003 and then carried out meiosis from Jan.26 to Feb.5. Microspores were released from tetrads on Feb.9. Through four times of continuous mitosis, microspore developed into five-celled pollen grain in later Feb.. The mature pollen consisted of two prothallial cell, a sterile cell, a spermatogenous cell and a tube cell. The pollination occurred in early Mar., lasting about 8 days. The study indicated that starch grains accumulated and disappeared regularly at different phase during pollen development. It was observed that there were two dominant peak accumulation of starch grains. One occurred just before the meiosis of the MMC taking place and another appeared before the microspore beginning mitosis. The amount of starch grains gradually decreased with the division of the cells. And it was showed that the distribution of starch grains changed regularly with the rhythm of pollen development. The starch grains aggregated gradually toward the equatorial region during the metaphase I and then moved to the daughter nucleus during anaphase I , and finally distributed to the four daughter cells equally when the meiosis of the MMC ended. During the maturation of pollen, the starch grains aggregated mainly around the nucleus. All of them disappeared before pollination.The Sudan Ⅲ test indicated that they changed into fat. But they appeared again in the pollen tubes after pollen grains were cultured in vitro and germinated. It was supposed that the reserve of starch grains in mature pollen was in line with ecophysiological adaptations such as the respective pollination syndrome rather than systematics.
A Study on the Relation between the Nutritional Needs of Ericerus pela(Chavannes) and Nutritional Component of Host Plants
WANG Zi-li, WANG Shao-yun, YE Shou-de, CHEN Yong, FENG Ying, CHEN Xiao-ming
2005, 18(4): 421-424.
Abstract:
The relation between nutritional needs of Ericerus pela and nutritional components of host plants are studied.The results showed that growth of the female Ericerus pela was correlated with mineral,protein,fat,vitamin and glucose.Wax secretion of the male Ericerus pela was related with mineral,water-solubility matter,fibrin and glucose.There are 15 amino acids of privet(Ligustrum vulgare) branches hosted by Ericerus pela lower than that comparative branches and total amino acids of privet(Ligustrum vulgare) branches decreased by 28.17% due to host of Ericerus pela. The results also showed that the growth of the female Ericerus pela needed K,Ca,Mn and Wax secretion of the male Ericerus pela needed K,Na,Ca,Mg,Fe,and Mn.
Discussion on Prediction of Wood Properties and Product Values of Plantation by Remote Sensing Technology
LIU Xing-e, JIANG Ze-hui, FEI Ben-hua, LI Zeng-yuan, PANG Yong, FAN Shao-hui
2005, 18(4): 425-429.
Abstract:
This paper discussed on how to estimate the tree crown parameters by remote sensing technique and there is a close relationship between the tree crown and wood properties. There is the possible connection among remote sensing technique, the canopy of crown and wood properties. The characters of the crown were analyzed using remote sensing image(eg.QuickBird) and the relation could be found between the crown indices and wood properties in order to predict wood properties and evaluate the utilization value, according to grown indices. The purpose is to provide some references for the evaluation of the wood properties and product economic values.
Relationship between Plant Diversity and Environment of Picea schrenkiana var.tianshanica Forest before and after Canopy Disturbances
LIU Yun, HOU Shi-quan, LI Ming-hui, PAN Cun-de
2005, 18(4): 430-435.
Abstract:
After canopy disturbance, because of the change of surroundings in gaps, the vegetations have corresponding responses. The article was based on the surveying of vegetation in gaps and non-gaps in 1999. The results were showed that abundant indexes in gaps were larger than that in non-gaps; individual ecological dominance degree indexs in gaps were 36.7% less than those in non-gaps; having 76.7% of evenness indexs in non-gaps were larger than those in gaps; Shannon individual abundant indexes in gaps were 66.7% larger than those in non-gaps. Various environment factors and plant diversity indexs had correlative relationship before and after canopy disturbance. In gaps, the main factors influencing plant diversity indexs were elevation, effective nitrogen, organic matter, full kalium, full phosphorus and general salt, but only effective nitrogen, organic matter, full kalium, full phosphorus and general salt had evident influnence on evenness indexs; in non-gaps, the main factors influencing plant diversity indexs were aspect of slope, location of slope,degree of slope, illumination intension, effective nitrogen, full kalium, full phosphorus and general salt, but only aspect of slope, degree of slope, illumination intension had evident influnence on individual ecological dominance degree indexs.
Study on Endogenous Phytohormone Changes in Poplar Hosts Infected by Ice Nucleation Active Bacterial Canker Disease
MAO De-jiang, ZHANG Ai-xia, ZHU Ya-ling, XIANG Cun-ti
2005, 18(4): 436-440.
Abstract:
The content of endogenous phytohormone like auxin and zeatin (a kind of cytokinesin) was higher in infected bark than that of in healthy bark, while the content of endogenous giberellin and abscisic acid droped in the diseased bark. The changes of endogenous phytohormone finally resulted in the development of swollen stem, slightly more active physiological state and decrease of the resistance to cold.
Impact Study on the Biodiversity of Yangtze Beaches Wetland in Anqing with Human Interference
CUI Li-juan, ZHANG Man-yin
2005, 18(4): 441-445.
Abstract:
Anqing beach wetland is a typical wetland along the lower and middle reaches of Yangtze River. The wetland is very important in maintaining the stability and the biodiversity riches of the ecosystems in the region. Biodiversity is an important function of wetland ecosystem. The plantation of wetland in Anqing varies greatly with reeds, Arundo donax, Salix matsudana, Populus deltoids. The paper mainly studied the functions of the three kinds of wetland: Salix matsudana wetland, Arundo donax wetland, and Populus deltoids wetland,compared the differences of plant biodiversity among the three kinds of wetlands. It is showed that the indexes of diversity and species richness were the highest in Populus deltoids wetland, and the lowest in Arundo donax wetland. The Simpson index was the biggest in Salix matsudana wetland, and smallest in Arundo donax wetland which indicated that the species dominance focused on a few plant species, but it is not so definite in the Arundo donax wetland. In the beach wetland of the middle and lower reaches of Yangtze River the herbs species were more concentrated. The index of eneness was the highest in planted Populus deltoids wetland, and lowest in Salix matsudana wetland. The biodiversity also varied according to the difference of altitude of wetlands. The law is that with the growth of altitude, the biodiversity will decrease. In Populus deltoids forest,the difference of forest age did nothing to the biodiversity and to the richness of plant species.
Virtual Water Consumption and Desertification Controlling in the Gonghe Basin, Qinghai Province
WANG Xue-quan, LU Qi
2005, 18(4): 446-450.
Abstract:
Virtual water strategy means regions whose water is scarce achieve their water security and food security by importing water-intensive products from those water is abundant, which expands the solution of water resources scarcity to the political-economic system. The particular linkage of population, food, and trade has been the masterstroke of virtual water strategy research. Using the methodology to assess the virtual water content in crop and livestock products, the paper analysed the virtual water content in product and circulating field in the Gonghe Basin. It calculates that the virtual water consumption for urban citizens is 878.43 m 3,while for rural citizens is 1 105.61 m 3. The results showed that the total product-related and consumption-related virtual water amount was estimated to be 19 633.61×104 m3 and 33 073.57×104 m3 respectively,these are over 0.9 and 1.5 times to the statistical water use volume of 2 1907.5 m3. The research also discussed the political implications and potential applicability of virtual water associated with water security,economic benefit and consumption structure in the Gonghe Basin. Virtual water trade is an instrument to achieve water security and efficient water use.
Artificial Culture of Haploporus odorus
WEI Yu-lian, ZHOU Bao-xiang
2005, 18(4): 451-454.
Abstract:
Haploporus odorus is a species of Basidiomycetes with fragrant anise-like aroma. Its culture study was made in laboratory. The results showed that optimum temperature for the mycelial growth was 33 ℃. Zymoid Extract was the best nitrogenous source. The fungus grew better at pH value as 6.0. Glucose was better among the selected carbonic sources.
Dynamic Caloric Value of Casuarina equisetifolia Litter Fall During Decomposition on Coast Sandy Land
ZHANG Qing-hai, YE Gong-fu, LIN Yi-ming
2005, 18(4): 455-549.
Abstract:
The Casuarina equisetifolia litter decomposition experiment site locates at Huian county in Fujian province, south of China. Caloric value were tested by oxygenic bomb caloric-meter. The aim was to expose the law of gross caloric value, ash free caloric value and ash content of litter during decomposition. The result showed the dynamic of the gross caloric value, ash free caloric value and ash content of Casuarina equisetifolia litter during decomposing. The decomposation lasted for three months with the caloric 21.40 kJ·g-1, to which decreased from the beginning gross caloric 21.67 kJ·g-1. At the tenth month, the gross caloric value was decreased to rock bottom, 20.48 kJ·g-1, with the range 1.19 kJ·g-1 to the begin value. After ten months of decomposation, the gross caloric value began to increase, then gross caloric value increased to 20.83 kJ·g-1 at the twelfth month, while with average decreasing ratio 0.07 kJ·g-1 per month; As to ash free caloric value, which the beginning ash free caloric 22.78 kJ·g-1, decreased to nadir, 21.89 kJ·g-1 at the ninth month, with the range 0.89 kJ·g-1 to the begin value. Then it increased faster than gross caloric did, up to 22.41 kJ·g-1 at the twelfth month. While it had average decreasing ratio 0.03 kJ·g-1 per month; The ash content, which had the contrary tendency to caloric, increased with time go by. But as the gross caloric, they all reflected the law of litter decomposition. It increased slowly from 4.88% to 4.90% in the beginning three months, then increased sharply. At the twelfth month, the ash content was up to 7.09%,and with average increasing ratio 0.184 point of percentage per month, in twelve months. While both caloric and ash content related obviously with temperature and soil temperature, especial the air temperature, so temperature was an important factor effecting the litter decomposition.
Potential Suitability Assessment of Bursaphelenchus xylophilus in China
LU Quan, WANG Wei-dong, LIANG Jun, YAN Dong-hui, JIA Xiu-zhen, ZHANG Xing-yao
2005, 18(4): 460-464.
Abstract:
Potential suitable area for the pine wood nematodes, Bursaphelenchus xylophilus were described quantitatively. According to its biological characteristics and relationship between its development and the environment, five key factors were chosen, namely yearly mean temperature, the mean temperature of July, June and August, altitude, days above 25 ℃ and precipitation. Their subordination functions were defined with math method of synthetic assessment on fuzzy mathematics. Climatic data of 639 sites obtained from State Weather Administration were processed by program of Qbasic 6.0 in order to get its subordination value, and comprehensive suitable value of every site was calculated by creation of fuzzy judgment matrix. Finally MapInfo 7.5 software was adopted for data collection, processing and analysis to make thematic map, five environmental types were graded according to comprehensive suitable value.
Establishment of Chinese Forest Plant Disease Information Management System
LIANG Jun, QU Zhi-wei, DAHU Ba-yaer, WEI Shu-hua, JIA Xiu-zhen, ZHANG Xing-yao
2005, 18(4): 465-470.
Abstract:
The forest plant diseases information system was established on the basis of Microsoft Visual Basic 6.0 and Microsoft Access 2000. The techniques used in the system are ADO, SQL language and intelligentized query. The sources of the database was based on Chinese forest disease occurred badly in recent decades and the forest plant disease specimen of Chinese Academy of Forestry. The database included three tables. They were forest plant disease specimen information table including 42 data fields, forest plant diseases information table including 39 data fields and user information table including 4 data fields. In order to make the database safe and easy to be managed, two kinds of users as common user and senior user were set. The senior users were allowed to manage the database, while the common users were allowed to query and browse the information only. With the system, the forest plant disease specimen of Chinese Academy of Forestry and the whole country's forest plant disease information could be managed. The system offering exact and blocking query service contained lots of particular forest plant diseases information and was easy to operate. So it would have a wide application outlook.
Anylysis of Vegetation Restoration Strategies in Severe Soil Erosion Area of the Loess Plateau in China
PENG Zhen-hua, DONG Lin-shui, ZHANG Xu-dong, ZHOU Jin-xing
2005, 18(4): 471-478.
Abstract:
The severe soil erosion area of Loess Plateau is mainly located at the middle reaches of the Yellow River,and the western part of Shanxi Province is one of the typical parts. In this paper, the current situation and prospect of vegetation restoration was analyzed in that area. The western part of Shanxi Province as the emphasis area of national soil ecology management, the vegetation restoration and construction has achieved some effect. But serve soil erosion trend wasn't be kept within limits, the strategy and technique of vegetation construction also had many problems.We discussed the problem, counter measure and future prospect of vegetation restoration. The western area of Shanxi Loess Plateau can be categorized into two parts by the geomorphic and vegetation features, one was earth-rocky forest zone mainly in the east of this region; the other was loess agricultural zone in the west by the Yellow River. Earth-rocky forest zone should close the hillsides to facilitate afforestation, This paper bring forward closing the hillsides to facilitate afforestation was the main instrumentality and the artificial promotion measures was assistant instrumentality as the long-term management strategy of secondary forest region.Otherwise the loess zone should prohibit pasture outside on hillside, or carry out rotation grazing. The level of the management and technique of artificial aforestation should be enhanced in time. For the target of reconstructing the vegetation of this area, we must change the extensive management of the economy. The policy of protection and closing the land should be attached enough importance to, we also should use more native trees than exotic trees. Only through these measures, the vegetation restoration and controlling the soil erosion may come true in the area of the western Shanxi Province.
Alien Pest Risk Analysis and Control Countermeasure of Solenopsis invicta Buren
ZHENG Hua, ZHAO Yu-xiang
2005, 18(4): 479-483.
Abstract:
The paper gives the pest risk analysis of the invasive species red imported fire ant (Solenopsis invicta Buren) including its distribution, latency and present damage degree, economical value of damaged object, spreading possibility and control difficulty referring to the methods of international Pest Risk Analysis (PRA). The PRA result was 1.861, and belongs to middle devastating pest in China. It must be strengthened to prevent the spreading and damage of the red imported fire ant by various control countermeasure of quarantine, monitor and so on.
Further Study on the Value of Forest Resources
LIN Wei-wei, GUO Quan-shui, NIU Shu-kui, WANG Chun-ling
2005, 18(4): 484-489.
Abstract:
Based on the analysis of the main theories of natural resources values, such as Labor value theory, Utility value theory and Energy value theory, the philosophical theories and the philosophical characteristics of forest resources'values were put forward. Dialectically the varying reflected forms and the varying evaluation methods of forest resources'values were analyzed. The authors pointed out the problems existed in the study on the evaluation of forest resource values in China. Furthermore some advices were given on the evaluation.
A Framework of Indicator System for Desertification Monitoring and Evaluation
WU Bo, SU Zhi-zhu, YANG Xiao-hui, LIU Wen, JU Hong-bo, LIU Yan
2005, 18(4): 490-496.
Abstract:
According to characteristics of desertification,the development and control processes of desertification consist of four parts:driving forces,desertified land,impact by desertification and desertification control.Therefore,indicator system for desertification monitoring and assessment includes four aspects:pressure,state,desertification impact and implementation.Pressure indicators characterize driving forces both natural and man-made,affecting the status of natural resources and leading to desertitication.Pressure indicators are used to assess desertification trends and make an early warning for desertification.Natual indicators describe natural factors,mainly climatic conditions,natural disasters,which promote the occurrence and development of desertification.Non-natural indicators desribe the pressure on land/ecosystems leading to land degradation from human activities.State indicators characterize the status of natural resources including land.The physical and biological features of desertitied land ecosystem are the main factors to be considered.Physical indicators describe the land characteristics,physical and chemical properties of soil and hydrologic features of the land ecosystem.Biological indicators are used to describe biological characteristical of the land ecosystem.Desertification impact indicators are used to evaluate the effects of desertification on human beings and environment.Implementation indicators are used to assess the actions taken for combating desertification and to assess its impacts on natural resources and human beings.Such impacts refer to improvements of socio-economic and natural conditions.The framework of the state indicator system is based on three aspects,namely agro climatic region,land use and degradation process.For the pressure,desertification impact and implementation indicators,the framework of the proposed indicator system is in reference to agro climatic regions.
Ficus and the Wasp Community within Syconia in Xishuangbanna
XU Lei, YANG Da-rong, PENG Yan-qiong, WEI Zuo-dong
2005, 18(4): 497-503.
Abstract:
In the tropical rainforests of Xishuangbanna the biological diversity is extremely rich,and the fig is a king of key plant species.It is the biggest tropical rainforest of China,and there has the most species of Ficus in China.There has all the 4 subgenus of Ficus,including 23 species and subspecies of Urostigma;4 species of Pharmacosyea;2 species and subspecies of Sycomorus,and 41 species,subspecies and variants of Ficus.Now 69 species,subspecies and var-species of Ficus was reported in Xishuangbanna,which takes 69.4% of all Ficus reported in China.There are the obligate pollinating wasp and some non-pollinating wasps in syconia.29 species of Ficus and 30 species specific of pollinators and more than 170 species non-pollinating wasps have been identified in Xishuangbanna,while many other Ficus species and their wasp communities have not been classified because of lacking samples.Pollinating and non-pollinating wasps,which interacts each other and affect the fig-pollinator mutualism,construch the complex wasp community in syconia.The study of this community now is in primary phase,and it requires more thorough and material compositive researches of ecology,biology,genetics and molecular biology.