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1.
IntroductionBal11booisl11ainfoodoftl1cgial1tpal1daint`.ildal1dman-fedgiantpandattasfCd111ucl1bal11boobcsldcsconccntratestl1atx`erel11adcofgrainPOwdcrtokccpltsfeedingl1abitsinwiId,buttl1cdigestivcratcofcoarsccclluloseisvery'low,il1botl1ttilda11d111a11-fcdpa11das.Wecanfindthattl1eba111boot'asall11ostl1otdigcstcdfrolllthefCccsthatcol1tai11edl11ucI1bal11boosticks.CI1cl1Yucllulletc.(l993)rcPortedt1lattl1edigcstit'eratcil1bal11boocoarsecelluloscisabout25%ol1lv.Tl1cautl1orsdesiglledthiscxPCrilll…  相似文献   

2.
IntroductionSchiSandraisadeciduousvineofMopohaceae.ItsthetStaSteofsWed,sour,bitter,PepPeryandsalty.ItisoneOfthetfadihonalChineseherbalmedicine.Schisan-for(Mopohaceae)hasbeenusedasprecioustonicandastriopntdrugforalleviahngcoughsinceanc1enthme.Modemmedicine…  相似文献   

3.
This study assessed ecological and socio-economic impacts of a participatory forest management project in the Republic of Benin. The study focused on the Wari-Maro Forest Reserve and the ‘Projet d’Aménagement des Massifs Forestiers’ five years after its completion. A forest inventory was carried out using 37 square plots of 729 m2 each to characterise the population structure of two types of plantations established: plantations with exotic species and plantations with native species. In addition, individual surveys were conducted with local households, organs of joint forest management and forestry officers to evaluate their perceptions about the participatory management of the plantations. Finally, the sustainability of the participatory management was assessed with an established rating system. Results showed that plantations with exotic species were more successful than plantations with native species. Local communities argued that they have not been involved in the plantations design but only in the implementation step and that their standards of living have decreased after the project completion. The rating system used showed that the participatory management of plantations had a short-term sustainability. The findings suggest that future projects should be designed and implemented with better participation of local communities as full partners.  相似文献   

4.
Ultrasound-associated extraction of seed oil of Korean pine   总被引:8,自引:1,他引:8  
Experiment on ultrasound- associated extraction of seed oil of Korean pine (Pinus koraiensis) was conducted in Northeast Forestry University, Harbin, China. The factors affecting extraction yield, such as ultrasonic frequency, extracting temperature, extracting time and the ratio of material to liquid (ratio of Korean pine seed to absolute alcohol), were analyzed under specific condition and the optimal extracting parameters were obtained as the ultrasonic frequency 32 000 Hz, the extracting temperature 80℃, the extracting time 50 rain, and the ratio of material to liquid 1: 30. The study demonstrates that ultrasound is a reliable and great efficiency tool for the fast extraction of Korean pine seed oil。  相似文献   

5.
Ginkgo biloba L. is a precious relic tree species with important economic value. Seeds, as a vital reproductive organ of plants, can be used to distinguish cultivars of the species. We chose 400 seeds from two cultivars of ginkgo(“Fozhi” and “Maling”;200 seeds for each cultivar) as the study material and used the Gielis equation to fit the projected shape of these seeds. The coefficients of variation(CV) in root mean squared errors(RMSE)obtained from the fitted data were used to compare the level of inter-cultivar variations in seed shape. We also used the covariance analysis to compare the allometric relationships between seed weights and projected areas of these two cultivars. The Gielis equation fitted well the seedshapes of two ginkgo cultivars. The lower CV in RMSE of cultivar “Fozhi” than “Maling” indicated a less symmetrical seed shape in the latter than the former. The bootstrap percentile method showed that the seed shape differences between the two cultivars were significant. However, there was no significant difference in the exponents between the seed weights and the projected areas of these two cultivars.Overall, the significant differences in shapes between the seeds of two ginkgo cultivars were well explained by the Gielis equation;this model can be further extended to compare morphological differences in other ginkgo cultivars, and even for plant seeds or animal eggs that have similar oval shapes.  相似文献   

6.
The study made a monetized valuation of eco-service provided by forests at Saihanba Mechanic Forest Farm in terms of water conservancy, soil conversation, carbon sequestration, micro-climate adjustment, air quality improvement, protection for agriculture, biodiversity maintenance, and landscape recreation. The results revealed that the total value of various eco-services is 3.061 billion yuan/a, while the eco-services of unit area forest values at 42 300 yuan/(ha·a).  相似文献   

7.
A Study of Collecting Robot of Conifer Cone   总被引:1,自引:0,他引:1  
IntroductionIntheforeStp~tion,thecollectionofconifcrconeisalmpsadifficultProblem.AlthoughmanykindsofconecoleCtinmachinehavebeenresearchedandmanufac-~athomeandabroad,forexample,elevator,vibra-tionmachineoftrdetrunkandsoon.ThesemachincshavcnotbeenaPPliedwid…  相似文献   

8.
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   

9.
Resonance flexural vibration(Fast Fourier Transform, FFT), ultrasonic wave(Pundit) and stress wave(Metriguard) techniques were examined as means of evaluating the static modulus of elasticity (MOE) and predicting the modulus of rupture (MOR) of finger-jointed lumber specimens made with four kinds of Eucalyptus (Eucalyptus. citriodora, E. exserta, E. grandis x E. urophylla and E. grandis). Dynamic MOE was calculated from frequency and time obtained from forced vibrations and sounds induced in the four species of finger-jointed specimens. It was found that correlation coefficients between density and static MOE and dynamic MOE were statistically significant at the 0.01 level. And it was also found that the three nondestructive techniques can provide rapid and accurate means to determine the MOE, and the dynamic MOE was more accurate to predict static MOE than density. But the correlation coefficient between dynamic MOE, static MOE and MOR were lower than results reported by other researchers for solid wood, and were not statistically significant. It can be concluded that the three nondestructive techniques are useful for evaluating the MOE, but not suitable for predicting the MOR of finger-jointed.  相似文献   

10.
11.
IntroductionLandscapecanbeconsideredaspatiaI1yheterogeneousarea,andspatialpatter11referstothearra11gementofstructurall1eterogeneityofenvironments,resourceandbiologicalsysteInsinspace(Formanetall986,Tur11erl987,l989-Risserl987,TurneretaI199l).Turner(1987,1…  相似文献   

12.
GeneralInf0rmati0nLaoshanExperimentalStationofPlantation,knownasakeyexperimentalbaseofplantationofNortheastForestryUniversity,wasestablishedinl958.ItislocatedonShangzhiCountyof'HeilonaiiangProvince,45"20,-45"25'in1atitudeand'l27o30,-l27o34'inlongitude.Themeanelevationisabout300In-ThehighestpeaknamedMaoershanis800minelevationralativeheight.Thes1opeinthisregionrangesfroml0"to15",andtheterrainisachainofundu1atedhills.Vegctati0nThezonalvegetationofthisregionisbroadleavedandkoreanpinemixedfO…  相似文献   

13.
Plantation poplar is one of the most important resources for wood industry, its utilization field is vast. The wettability of Populus tomentosa with different drying methods was judged by measurement of contact angle using distilled water in this paper. The results showed that the specimens from conventional drying have the biggest contact angle, and the air dried have the smallest contact angle, air dried lumbers have a better wettability than the kiln dried. The changes of contact angle in a period of tim...  相似文献   

14.
The corrosive rates of 4 types of metals as well as epoxy-coated metal in a variety of preservatives derived from different copper sources and ingredients were .measured in this paper. The main results show that: CCA is less corrosive to red brass and Q235A steel than other copper formulations; Copper-based preservatives such as ACQ and CuAz derived from basic cupric carbonate or cupric hydroxide are much less corrosive to Q235A steel than those from cupric sulfate; Ethanolamine is less corrosive to Q235A steel than ammonia in ACQ derived from cupric hydroxide, while other ingredients are the same; Epoxy resin coating could be used for protecting red brass, Q235A steel and zinc hotdipped galvanized mild steel from corrosion.  相似文献   

15.
lntroduCtionlnthewoodworkingprocess,itisusualIynecessarytodeterminethebest-orientedcenterofIog-whichisespeciaIlyimportantforpeelingbIocks-Howmuchpercentagerecoveryisconsideredtobethejudge-mentifitisthebestIogcenter,soitisnecessarytofindoutthemaximuminscribedcylinder.Therefor,themainproblemofIogcenteringistodescribethreedimensionsoutlineoflog.ThisworkisSupiortedbyNaturalScienceFoundationofHeilongjiangProvinceMethodsltisnecessarytoscanIogatseveraIcross-sectionsandmanydifferentpointsinorder…  相似文献   

16.
Bacterial wilt caused by Pseudomonas solanacearum, is a very serious disease of Eucalyptus in southern China, mainly in Guangdong, Hainan and Guangxi provinces. It causes the death of seedlings and young trees and the mortality may exceed 90 percent in some sites. Susceptible species include E. grandis, E. urophylla, hybrids between the two and E. citriodora. In nursery and field trials with E. urophylla and field trial with E. grandis x E. urophylla inoculation of ectomycorrhizal fungi was found to reduce the incidence of the disease. Some fungal isolates were more effective than others.  相似文献   

17.
Introducti0nChangbaiLarch(LarixolerI1sis).traditionaIIy,isaspeciesbyseedpropagation.ltdosenotconsistentIyproduceseedsinhighyieIdeveryyear-sothatl1ighqualityseedsfroIntheseedorchardscannotmeetlheneeds0freforestati0ninlargearea.Forthisreason,astudyoPcutting…  相似文献   

18.
AtthementionofHubei,peoplecanstillbringtomindthereputationof"provinceof1000lakes".Butthesceneof"waterandskymergingintoonecoloramidinterchangedfishermen'ssongs"hasalreadyfadedfrompeople'smemory.WhenIwalkedintothislandinsearchoflakesthateitherhavedis-appear…  相似文献   

19.
20.
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   

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