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1.
IntroductionAtpresent,thcrearel11anyl11etl1odstodccidefbodco11-stiintion8fherbivores,sucI1asstol11acl1a11al}'sis,fcccsanalysisanddirectobservation.Sol11co11calsouscdesoPl1agusfistulal11etl1odtoanalyzc.Sincel97(),fecesanalysiswaswildlyusedbecauseofitseasiersampIinganditslittledisturba11cetoanimal(Vavractal,l98(),Norburg,l988,GaoZl1o11gxinctal,l99l).Tllisnlctllodt`asalsouscdintI1isstud}'.Tllccxpcri-lllclltaln1aterialcamcfron1XinbarI1uyou,HuIUI1bcir,tvllicllI4'bctWccnlol1gitudcll5"-ll7"48'… 相似文献
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IntroductionMongoliangazelle(PrOCSPraguttuross)isaspecialruminantspeciesthathasnumerouspopulationsintheeasternpaFtofNetMonggolGrasslandandasignificantcomponentofthegrasslandecosystem.Thisspecieshasthehabittoselectspeciesandqualityofplantstograze.However,thepopulationhasdecreaseddramaticallyandfacesextinctioninChina(JiangetSI.1998).Therefore,itisveryimportanttostudythefoodhabitsandfoodchoicebyMongoliangazelleforpromotingtheprotectionandmanagementofremainingpopulation.Inapreviouspaper(Gao… 相似文献
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The food availability, composition of the diets and selective grazing of the Mongolian gazelle (Procapra gutturosa) were studied in Hulunber Grassland in Nei Monggol. The food availability of Mongolian gazelle showed seasonal changes. The
plant biomass was higher in spring and summer than that in autumn and winter. The fecal compositions of the gazelle demonstrated
that fibrous parts occupied 62.4%, 74.8%, and 66.0% in spring, autumn, and winter, respectively. The Mongolian gazelle preferred
to grazeCompositeae, Leguminosae, Allium spp. and other forbs in spring and autumn, while the grasses, such asAneurolepidium chinense andStipa spp. were selectively feeding in winter.
Responsible editor: Zhu Hong 相似文献
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呼伦贝尔沙地扩展和危害日益严重,为了保护呼伦贝尔大草原,有效治理草原沙漠化土地,在呼伦贝尔沙地不同分布区、不同立地类型建立不同的治理造林模式。经试验研究,平铺式沙障适合平缓流动沙丘,直立式沙障适合高大的流动沙丘。 相似文献
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lntroductionWiIdlifemanagersdesirereIiableindicatorsofnu-tritionaIstatusoffree-rangingunguIatestoassessreIationshipsbetWeenhabitatsandpopuIations.ThenutritionaIconditionofunguIatesisstrongIyaffectedbytheirfOodquality,andasunguIatesreguIarlyexpe-riencenitrogenshortages(White1978IRobbins1983),itispaFticuIarlyimportanttoknowthenitrogenconcentrationoftheirfoodpIants.onecommonmethodofestimatingquaIityofungulatedietsisana-IysisnutritionaIquaIityofforagepIantsgrowinginhabitats.However,indisc… 相似文献
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半固定沙地植苗造林治理模式 总被引：1，自引：0，他引：1
呼伦贝尔沙地扩展和危害日益严重,为了保护呼伦贝尔大草原,有效治理草原沙漠化土地,在呼伦贝尔沙地不同分布区、不同类型立地进行了3个试验区的沙地造林试验,结果表明:3个试验区造林成活率都很高,固沙效果明显;陈巴尔虎旗和新巴尔虎旗试验区因牲畜啃食和浇水不及时而致保存率偏低;鄂温克旗采取网围栏全封措施,而保存率较高;3个试验区都有天然樟子松和杨树分布。 相似文献
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Introduction7Riney(1982)statedthatbodyphysicalconditionofanimalsrespondquicklytoenvironmentalchangesandprovideagoodindextoapopulation'sresponsetothesechangesafterminimaltime-lag,thusfacilitatingamorepreciseunderstandingofcause-effectinterrelationsbetweenanimalsandtheirenvironment.Inthisregard,ameasurementoffatreservesprovidesthebestindextothephysicalconditionofawiderangeofmammal(Riney1955).Formeasuringcarcassfat,variousmethodshavebeendevisedandproposed.Thesemethodsincludekidneyfatindex,bonema… 相似文献
10.
A landscape model (LANDIS) was used to study the long-term forest dynamics under five planting types (100% larch (P1); 70% larch and 30% Mongolian Scotch pine (Pinus sylvestris var. mongolica) (P2); 50% larch and 50% Mongolian Scotch pine (P3); 30% larch and 70% Mongolian Scotch pine (P4); 100% Mongolian Scotch pine (P5)), which were also employed in severely burned area under current planting intensity, and under natural regeneration (as
a comparison) in Tuqiang Forest Bureau in the northern slopes of Great Xing’an Mountains after the catastrophic fire in 1987.
Results showed that different planting types had a significant influence on the abundance of larch, Mongolian Scotch pine
and white birch. The abundance of larch increased with time, whereas the abundance of Mongolian Scotch pine was in a converse
way. The abundance of larch and Mongolian Scotch pine under these planting scenarios was higher than that under natural regeneration.
Under these planting scenarios, the abundance of larch increased with the increasing proportion of larch, and the abundance
of Mongolian Scotch pine was in a similar way. Contrary to larch and Mongolian Scotch pine, white birch had higher abundance
under natural regeneration than that under these planting scenarios. Also, the different proportions of larch and Mongolian
Scotch pine had an influence on the abundance of white birch. White birch had higher abundance with the increasing proportion
of Mongolian Scotch pine. As for the total abundance of larch and Mongolian Scotch pine, the difference was not significant
under P2, P3 and P4 scenarios, but was higher than that under P1 and P5 scenarios, which indicated that individual-species planting should not
be used in the forest landscape.
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Translated from Chinese Journal of Applied Ecology, 2006, 17(5): 855–861 [译自: 应用生态学报] 相似文献
11.
The role of ectomycorrhizal fungi in alleviating pine decline in semiarid sandy soil of northern China: an experimental approach 总被引：1，自引：0，他引：1
Jiao-jun Zhu Feng-qin Li Mei-ling Xu Hong-zhang Kang Xiang-yun Wu 《Annals of Forest Science》2008,65(3):304-304
The decline of Mongolian pine (Pinus sylvestris var. mongolica) trees on sandy land in northern China has caused serious ecological concerns. Mongolian pine is an ectomycorrhizal fungus (ECM)-dependent species. Three ECM species (Boletus sp., Lactarius deliciosus and L.sp.) were collected from Mongolian pine plantation stands to test their beneficial effects on Mongolian pine seedlings and their responses to environmental factors such as pH, drought stress and temperature. The results indicated that ECM inoculation significantly increased the rate of ECM colonization and the length of seedling shoots. The three ECM could grow in a pH range from 4 to 7, but did not grow under heavy drought stress (?1.53 MPa). High temperatures (over 37 °C) caused death of ECM. When related to soil pH, soil water content and temperature in the Mongolian pine plantations, water conditions and temperature were unfavorable for ECM growth in surface soil, but suitable in deeper soil. Therefore, it was concluded that the failure of natural regeneration in Mongolian pine plantations might be influenced by the lack of ECM in the surface soil because of high temperatures causing ECM death. Moreover, the majority of the root area is distributed in deeper soil, which alleviates the stresses on ECM development and arrests pine decline; this is beneficial for tree growth. 相似文献
12.
本文明确的论述了在大、小兴安岭和呼伦贝尔林区存在多年的冻土地区及冻土对地基的重大危害。并全面的分析工程上具体实例。对解决多年冻土地区,出现破坏性冻裂和冻土地区的地基处理起到积极作用。 相似文献
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lntroductionOfaIImammals,theruminantshavethemostdif-ferentiated,specializedandcompIexstomachs,whichappeartobethebestsuitedfordigestingandutiIizingfeedrichincellulose.Hofmann(1972)statedthattheruminantstomachwasstructuraIIyadaptedtoutilizecertaindistincttypesoffoodattercomprehen-siveIycomparedthestomach-structureof26of31easternAfricanruminants.Accordingtotheirstom-ach-structureandfoodfeature,theseruminantsmaybegroupedintothreemaintypesoffeeder'a)bulkandroughageeaters(grazers)lb)seIectorsofju… 相似文献
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以吉林省汪清林业局金仓林场2块面积为0.25 hm2的蒙古栎天然中龄林固定样地为对象,采用8个竞争指标,研究蒙古栎天然林种内、种间竞争状态。研究结果表明,该林分竞争激烈,蒙古栎与其他各树种存在种间竞争,但其主要竞争压力来自种内,种外竞争压力主要来自黑桦与白桦。其它树种的竞争主要为种间竞争。蒙古栎竞争能力处于中等,白桦与黑桦最强。各竞争指标结果存在差异性,但均能反映蒙古栎天然林竞争状态。蒙古栎竞争强度与胸径存在幂函数关系,竞争强度随个体大小的增大而减小。 相似文献
16.
蒸汽压力对热处理材力学性能影响的机理研究 总被引：2，自引：0，他引：2
通过对樟子松和柞木分别在常压和一定蒸汽压力下进行热处理,比较了不同热处理木材与常规对照材的力学性能差异。结果表明:热处理使木材的抗弯强度和冲击韧性出现明显下降,然而,就抗弯弹性模量和顺纹抗压强度而言,除樟子松的MOE指标外,经过热处理的试材的性能指标都高于对照材。和常压热处理相比,压力蒸汽热处理进一步降低了试材的力学强度,但这一差异并不显著。木材化学组分分析表明,热处理材力学性能的变化主要归因于热处理过程中木材半纤维素的降解以及木素在热处理过程中的化学变化。 相似文献
17.
Comparison of stand structure and growth between artificial and natural forests of Pinus sylvestiris var, mongolica on sandy land 总被引：2，自引：0，他引：2
ZHUJiao-jun FANZhi-ping ZENGDe-hui JIANGFeng-qi MATSUZAKITakeshi 《林业研究》2003,14(2):103-111
Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in “Three North” regions (North, northwest and northeast of China), but many prob-lems occurred in the earliest Mongolian pine plantations in 7hanggutai, 7hangwu County, Liaoning Province (ZZL). In order to clarify the reason, comprehensive investigations were carried out on differences in structure characteristics, growth processes and ecological factors between artificial stands (the first plantation established in ZZL in 1950s) and natural stands (the origin forests of the tree species in Honghuaerji, Inner Mongolia) on sandy land. The results showed that variation of diameter-class distributions in artificial stands and natural stands could be described by Weibull and Normal distribution models, respectively.Chapman-Richards growth model was employed to reconstruct the growth process of Mongolian pine based on the data from field investigation and stem analysis. The ages of maximum of relative growth rate and average growth rate of DBH, height, and volume of planted trees were 11,22 years, 8, 15 years and 35, 59 years earlier than those of natural stand trees, respectively. In respect of the incremental acceleration of volume, the artificial and natural stands reached their maximum values at 14 years and 33 years respectively. The quantitative maturity ages of artificial stands and natural stands were 43 years and 102 years respectively. It was concluded that the life span of the Mongolian pine trees in natural stands was about 60 years longer than those in artificial stands. The differences mentioned above between artificial and natural Mongolian pine forests on sandy land were partially attributed to the drastic variations of ecological conditions such as latitude, temperature, precipitation, evaporation and height above sea level. Human beings‘‘ disturbances and higher density in plantation forest may be ascribed as additional reasons. Those results may be potentially useful for the management and afforestation of Mongolian pine plantations on sandy land in arid and semi-arid areas. 相似文献
18.
In bottomland hardwood forests, partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife like Louisiana black bear (Ursus americanus luteolus), white-tailed deer (Odocoileus virginianus), and Neotropical migrants. Although partial cutting may be beneficial to some species, those that use dead wood may be negatively affected since large diameter and poor quality trees (deformed, moribund, or dead) are rare, but normally targeted for removal. On the other hand, partial cutting can create dead wood if logging slash is left on-site. We studied foraging behavior of pileated woodpeckers (Dryocopus pileatus) in one- and two-year-old partial cuts designed to benefit priority species and in uncut forest during winter, spring, and summer of 2006 and 2007 in Louisiana. Males and females did not differ in their use of tree species, dbh class, decay class, foraging height, use of foraging tactics or substrate types; however, males foraged on larger substrates than females. In both partial cut and uncut forest, standing live trees were most frequently used (83% compared to 14% for standing dead trees and 3% for coarse woody debris); however, dead trees were selected (i.e. used out of proportion to availability). Overcup oak (Quercus lyrata) and bitter pecan (Carya aquatica) were also selected and sugarberry (Celtis laevigata) avoided. Pileated woodpeckers selected trees ≥50 cm dbh and avoided trees in smaller dbh classes (10–20 cm). Density of selected foraging substrates was the same in partial cut and uncut forest. Of the foraging substrates, woodpeckers spent 54% of foraging time on live branches and boles, 37% on dead branches and boles, and 9% on vines. Of the foraging tactics, the highest proportion of foraging time was spent excavating (58%), followed by pecking (14%), gleaning (14%), scaling (7%), berry-eating (4%), and probing (3%). Woodpecker use of foraging tactics and substrates, and foraging height and substrate diameter did not differ between recent partial cut and uncut forest. Partial cutting designed to improve or maintain habitat for priority wildlife did not affect pileated woodpecker foraging behavior or availability of selected trees compared to uncut forest in the short term. 相似文献
19.
北京雾灵山保护区蒙椴林空间点格局分析 总被引：2，自引：0，他引：2
根据北京雾灵山自然保护区蒙椴林样地调查资料,采用点格局分析方法,对该群落的树种组成、优势种群及不同发育阶段种群的空间分布格局及其相互关系进行了研究。结果表明:1)蒙椴林中乔木层共有9个种群,种群密度差异较大,蒙椴种群的株数比例和断面积占有明显优势。2)蒙椴林优势种群的分布格局和空间关联性与空间尺度的关系密切,在研究尺度范围内,蒙椴种群和山杨种群均呈显著性聚集分布,白桦种群呈随机分布。优势种群的空间关联性以负关联为主,种间竞争激烈。3)不同发育阶段个体的空间格局随尺度的变化明显,大树在整个空间尺度上呈现随机分布,中树和幼树在中小尺度上(r<24m)呈显著性聚集分布,在较大尺度上呈随机分布。不同发育阶段种群之间空间关联性以负关联为主,当空间尺度大于临界值时,大树和中树、幼树的空间关联性减弱,而中树和幼树的负关联增强。 相似文献