首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 661 毫秒
1.
As one of the four civilizations, China is enriched with brilliant traditions and cultures. The crane culture is a unique ?ower in this garden of cultures. Over thousands of years, crane has been featured in numerous graceful and tasty artistic images and…  相似文献   

2.
This paper, from the development of Chinese economy and forest resources as well as the fast-growing and high-yield timber plantation development program and harvesting policies of plantation, analyses the Eucalypt planting, processing, utilization and developing prospect in tropical area.  相似文献   

3.
Five minerals or elements, crude protein, lysine, methionine cystine, calcium and phosphorus, were selected for evaluation of the food value of seabuckthorn (Hippophae rhamnoides ssp. sinensis) using the method of "food analysis". The decision values (δi) of seabuckthorn seeds, leaves and fruit residues rank in the fifth, sixth and ninth position among the 16 types of fodder. Seeds, leaves and fruit residues of seabuckthorn are suitable for livestock and poultry fodder. The weights of livestock and poultry are considerably increased after feeding with seabuckthorn. The development of seabuckthorn should have great potentials as food, pre-food and food additives for livestock and poultry in north China. Processing facilities should pay more attention to seabuckthorn food development methods and strategies and the seabuckthorn fodder industry should be promoted.  相似文献   

4.
Up until 2009, 2541 nature reserves had been established in China. However, the process of developing this system of nature reserves was not quite smooth. Various kinds of information related to nature reserves, such as annual growth, the type of nature reserves established, motives behind building a nature reserve, legal instructions and the constitution of government sectors, were collected and analyzed in order to highlight the characteristics of the devel- apment of our nature reserve system. As a result, we identify three phases and their characteristics, i.e., the initial phase from 1956 to 1978, the establishment phase from 1979 to 1996 and the management standardization phase from 1997 to 2009, could be clearly identified. It is suggested that since the establishment of this comprehensive structural frame- work in China, the system should be entering a new developing phase. We recommend that more attentions should be paid on how to guarantee effective management and how nature reserves are able to maintain their value and fulfill their abjectives in the future.  相似文献   

5.
1 INTRODUCTIONChinese forest volume ranks high in the world,following Russia, Brazil, Canada and America. Buton the average, there is a great shortage of woodresource in China. With the increase of demandsfor wood and wood products, wood resource isobviously deficient. Though plantations have beenplanted widely in order to reduce the pressure ofdemands for wood to some extent, some of themwere planted blindly and the value in use is still low.How to make full use of the limited forests …  相似文献   

6.
Crane species are a unique creature category in the natural ecological system. They enrich our life with colors and poetic sensation and add vigor and vitality to the nature through their various colorful feathers, gracious and gentle songs and varieties …  相似文献   

7.
Woody plants contribute to the stability and productivity of terrestrial ecosystems and are significantly affected by climate change.According to the concept of environmental hormesis,any environmental stressors can cause hormesis,that is,stimulation in low doses and inhibition in high doses.Numerous studies have demonstrated plant hormesis under low doses of various abiotic stressors.However,the hormetic responses of woody plants to abiotic stressors from climate change are insufficiently studi...  相似文献   

8.
Distribution of solanesol in Nicotiana tabacum   总被引:1,自引:0,他引:1  
Solanesol is an important secondary metabolite in Nicotiana tabacum. Distribution of solanesol in Nicotiana tabacum was investigated by High Performance Liquid Chromatography (HPLC) method. The quantitative distribution of solanesol in various organs and tissues of N. tabacum showed that solanesol content, obviously different in all organs, was 6.8, 18.3, 27.5, 45.8, and 68.0 times higher in leaves than that in the stalks, flowers, seeds, fruits and roots, respectively. The contents of solanesol in various parts of leaf, stalk and flower were determined. The content of solanesol in top leaf, middle leaf and bottom leaf gradually decreased (6.124, 5.813 and 5.687 mg.g^-1, respectively) and the content of solanesol in various leaf-parts (leaf apex, leaf middle and leaf base) also gradually decreased. The content of solanesol in top stalk was 1.19 times and 1.92 times higher than that in the middle stalk and the bottom stalk, respectively. The content of solanesol in various tissues of stalk (epidermis, cortex and stele) dramatically decreased. The sepal contained higher concentration of solanesol (1.192 mg·g^-1) compared to any other parts in flower. The study will provide the base data for the regulation and control of solanesol, moreover, it will provide the scientific evidences for the rational development and utilization of N. tabacum resources.  相似文献   

9.
Siberian moth Dendcrolimus superans sibiricus Tschetw. is the main important insect pest not only in Siberian coniferous taiga, but it often forms foci of mass reproduction in larch stands in the Russian Far East. This article has described outbreaks of the Siberian moth and other insect pests since 1960 till now.  相似文献   

10.
Zhalong Nature Reserve is located in the border areaof Qiqihaer City, Fuyu County, Lindian County andTailai County of Heilongjiang Province. The area ofthe reserve is 210 000 ha. The reserve is the firstnature reserve for protecting wetland and crane inChina. There were more than 300 red-crownedcranes here at the very most. Zhalong Nature Reserveis situated at the Songnen Plain, the lower stream ofthe Wuyuer River. It is the biggest nature reserve inChina that takes crane and wetland …  相似文献   

11.
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended.  相似文献   

12.
1 INTRODUCTIONDevelopment of urban area is often expressed byexistence of growth of city physical, which is moredetermined by existing facilities and basic facilities.Development of urban area indicates tendency for theminimization of green air space as well as eliminatingnatural cover. Many land functions have been changedto become shops, settlements, recreation places,industrial and others.With growing of ability and prosperity of society,development of urban area continues to accelerat…  相似文献   

13.
Bacteria fertilizer is used most widely among all kinds of microbial fertilizers. We summarize the research headway of bacteria fertilizer. It mainly focuses on bacteria fertilizer improving the stress resistance of plant. Then we can offer basis to research and exploit bacteria fertilizer. These bacteria include azotobacter, photosynthetic bacteria, Bacillus mucilaginosus siliceous, phosphorus bacteria, plant growth-promoting rhizobacteria(PGPR), effective microorganism(EM).  相似文献   

14.
1ThisprojectissupportedbyHuoYingdongScicnceFoundationIntroductionSpatialhcterogencit}(Sfl),\`hicl1isgcncrall}'dcfincdasthecompIcxityandt'ariabilit}ofas}'stc111propcrt}'(c.g.,vegetationtyPe,populationdcnsity7,plantbiol11ass-soilnutrients)inspacc'isofgrcati…  相似文献   

15.
IntroductionBiochemicaIanaIysisaboutvariousorgansofdif-ferentplants,indmerentgrownstagesandhabitats,hasbecomeanimportantwaysforprovidingnewcharacteristicsandnewinformationinplantcIassifi-cation.IsoenzymeisakindofzymesexistedinmanydifferenttissuecelIs,ofwhichstructuresarenotex-actIysame,butcancataIyzeasamekindsofchemi-caIreaction.AsisknowntoaII,theform8tionofzymeiscontrolIedbyoneormoregenes,soitisadirectproduCtofgepeexpressionandcanbetakenasabiochemicaItargetofgeneexpression.Asthespeci-esi…  相似文献   

16.
China is the most populated country in the world, andits land area is not the largest, especially its cultivatedland is gradually declining with socio-economicdevelopment. In order to meet the demand to grain,vegetable and so on, wasteland must be reclaimed(Zhang Jianfeng, 2004). In China there is a large scaleof salt-affected land, e.g. in Lop Nur 5 000 km2, inTurfan almost the same, in Quidam Basen 20000 km2 (Gong Hongzhu, et al, 1984). Owing toadverse conditions crops growing in salty s…  相似文献   

17.
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it iscriticized that the cun~nt natural resource and environmental management and the policies in China have some problems unsolvedsince the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts madetheoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flowwith Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system includedenvironmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservationand construction industry and renewable resource production incentive system that turn the direct administration and operation tomanagement and services. The detail figure of the new model of cost-benefit flow is provided and the main points related arediscussed in this paper.  相似文献   

18.
1THEIMPORTANTMEANINGOFCFF1.1CFFHistoricalBreakthroughofChineseEcologyEnvironmentConstructionAtpresent,theareaofwaterandsoilerosionismorethan3.6millionkm2,andthedesertifiedlandsupto1.74millionkm2,correspondto18.2oftherealmarea(ZhouShengxian,2001).ThemainreasonforwaterandsoilerosionandlanddesertificationinChinaisdestructionofforestsandcultivation,whichresultsinenvironmentaggravationandmorenaturalcalamity(ZhangPeichang,1993;ZhangZhida,1997).Atthebeginningofthecentury,Chinesegovern…  相似文献   

19.
An understanding of forest carbon budgets, such as the factors that influence different levels of carbon accumulation, is one of the first steps in protecting and restoring areas of plant cover. Univariate and multivariate regression analysis was applied to evaluate the influence of climate variables (Rainfall, and mean maximum and minimum temperatures) on intra-annual above-ground carbon accumulated in tree species of the Caatinga. Above-ground carbon accumulated in the trees was 0.06 Mg ha?1 month?1. Carbon allocation in the aerial parts of the trees increased significantly with rainfall. Maximum and minimum temperature had little influence on carbon storage; however, variations in carbon accumulation are best explained when minimum and maximum temperatures are added to the regression model for rainfall, thereby demonstrating the simultaneous effect of these variables, and better explaining the carbon increase.  相似文献   

20.
1 INTRODUCTIONThe Loess Plateau is the most drastic soil erosion regionin China, with the most severe water erosion. Thedistribution of types and intensity of erosion not onlyhave regional diversity but also have perpendicularvariation. In the small watershed, there are differencesin erosion characters among its upper, middle and lowerreaches. It is very significant for taking rationalmeasures of soil and water conservation and forpreventing soil and water loss to analyze the relationbe…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号