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1.
里骆林区常绿阔叶林和人工杉木林气候水文效应   总被引:13,自引:2,他引:11  
里骆林区常绿阔叶林和人工杉木林气候水文效应黄承标,文受春(广西农学院林学分院南宁530001)(广西龙胜县林业局541700)ClimaticandHydrologicalEffectsofEvergreenBroad-leavedandArtificialChineseFirForestsinLiluoForestedRegion¥HuangChengbiao(ForestryCollege,CuangxiAgriculturalUniversity,Nanning530001),WenShouchun(ForestryBureau,LongshengCounty,Guangxi541700);ChineseJournalofEcol-ogy,1993,12(3):1-7.Siteinvestigationsandresearchesin1980-1990showthatevergreenbroad-leavedandartificialChinesefirfOrestsinLiluoforestedregioncanreducethevariationrangeofatmosphericandsoilt  相似文献   

2.
洞庭湖滩血吸虫易感地带保水生态灭螺的试验研究张元培,朱南屏(湖南省水产科学研究所沅江413100)(湖南省华容县血防站414200)EcologicalEIiminationofSnail(Oncomelania)byRctainingWaterinBloodFluke(Schistosoma)Suscepti-bleRegionsAroundDongtingLake¥.ZhangYuanpei(InstituteofFisheriesResearchofHunanProvince,Yuanjiang413100),ZhuNanbing(StationofSnailFeverControlofHuarongCounty,HunanProvince,414200).ChineseJournalofEcology,1993,12(3):23-25.Inbloodfluke(Schistosoma)susceptibleregionsofthelakebeach,experimentsofwaterinundatedelimi-natingsnail(Oncomelania)arecarriedoutbybuil  相似文献   

3.
柞蚕林生物生产力和干物质转化研究   总被引:5,自引:0,他引:5  
柞蚕林生物生产力和干物质转化研究温达志,杨思河(中国科学院华南植物研究所,广州510650)(中国科学院沈阳应用生态研究所,110015)姜波(辽宁省蚕业科学研究所,凤城118101)BioproductivityandDryMatterTransferofTussah-FeedingOakForest¥WenDazhi(SouthChinaInsti-tuteofBotany,AcademiaSinica,Guangzhou510650),YangSihe(InstituteofAppliedEcology,A-cademiaSinica,Shenyang110015),JiangBo(InstituteofSericulturalScience,Fengcheng,LiaoningProvince113100).ChineseJournalofEcology,1993,12(1):5-10.ThepresentstudydealswiththebioproductivityanddrymattertransferofChineseTussah-feedingoakforestinhillyareaofe  相似文献   

4.
祁连山植被水文效应的多层次Fuzzy综合评判   总被引:8,自引:0,他引:8  
祁连山植被水文效应的多层次Fuzzy综合评判车克钧,傅辉恩(甘肃省张掖祁连山水源林研究所734000)Multiple-LevelFuzzyComprehensiveEvaluationonHydrologicalFunctionsofVegetationsontheQilianMountains¥.CheKejun;FuHuien(QilianMountainsInstituteofForestforWaterSourceConservation,Zhangye,GansuProvince734000).ChineseJournalofEcology,1993,12(3):31-35.BymeansofmuItiple-levelfuzzycomprehensiveevaluation,thehydrologicalfunctionsoffourvegetationtypesareanalyzed.PiceacrassifoliaforestisshowntobethebesttypeforwaterconservationonQilianmountains,Sabinaprzewlskiiforesta  相似文献   

5.
杉木火力楠混交林根系的研究   总被引:28,自引:0,他引:28  
杉木火力楠混交林根系的研究李振问,杨玉盛,吴擢溪,赖仕嶂(福建林学院,南平353001)(福建尤溪县林业科学研究所,365200)RootSystemofMixedStandofChineseFirandHomana ¥LiZhenwen;YangYusheng(FujianForestryCollege,Nanping353001),WuZhouxi;LaiShizhang(ForestryResearchInstituteofYouxiCounty,Fu-jianProvince365200).ChineseJournalofEcology,1993,12(1):20-24。Therootsystemofa6-yearmixedstandofChinesefirandHomanaisstudiedby"soilcolumn"and"standardsampletree"methods.Thefineroot(lessthan2mmindiameter)biomassofindividualtreeofChinesefirinmixedstandis14.5%higherthaninpurestand,w  相似文献   

6.
我国南海海龟资源的调查与保护研究现状与展望王亚民(中华人民共和国农业部水产司,北京100026)AchievementandPerspectiveoftheResearchesonSoutbChinaSeaTurtleResourcesandProtectioninCbina¥WangYamin(DivisionofScienceandTechnology,DepartmentofFishery,People’sRepublicofChinaMinistryofAgriculture,Beijing100026).ChineseJournalofEcology,1993,12(6):60-61.ThispaperintroducestheresearchesinfieldofSouthChinaSeaturtleresourcesandprotectioninChina.TherearefivespeciesseaturtlesinChina,about90%ofthemliveinSouthChinasea。During1959-1988,3184.Itseaturtlewerecatched(about  相似文献   

7.
中国对虾cDNA文库的构建   总被引:26,自引:0,他引:26  
中国对虾cDNA文库的构建CONSTRUCTIONOFcDNALIBRARYOFSHRIMPPENAEUSCHINENSIS(CRUSTACEA,DECAPODA)关键词中国对虾cDNA文库构建KeywordsPenaeuschinensis,cDN...  相似文献   

8.
白介素10的临床应用研究   总被引:2,自引:0,他引:2  
言慧  黄树其 《生命的化学》1999,19(4):192-195
1989年,Fiorentio等发现Th2细胞分泌一种能抑制Th1细胞功能的未知因子,称为细胞因子合成抑制因子(cytokinesynthe-sisinhibitoryfactor,CSIF)。Moore等发现CSIF与EB病毒(EBV)中BCRF-...  相似文献   

9.
中国紫堇属新分类群*苏志云(中国科学院昆明植物研究所,昆明650204)NEWTAXAOFCORYDALISFROMCHINASuZhiyun(KunmingInstituteofBotany,ChineseAcademyofScience,Kunm...  相似文献   

10.
福建中亚热带村级农业生态经济类型的成因与发展机制研究林文雄,吴志强,林群慧,郑世庆,王松良,梁义元(福建农学院,福州350002)ContributingFactorandDevelopmentMecbanismofRuralAgro-ecolomicTypesinMid-subtropicalRegionofFuJianProvince¥.LinWenxiong;WuZhiqiang;LinQunhui;ZhengShiqing;WangSongliang;LiangYiyuan(FujianAgriculturalCollege,Fuzhou350002).ChineseJournalofEcology,1993,12(2):66-68.Usingsystematicanalysismethodtheauthorsstudiedthestatuecharacteristicsandtheirvariationpat-ternsofruralagro-ecolomictypeinmid-subtropicalregionofFujianprovince.11tapesofsystemstructurean  相似文献   

11.
The western part of the Mediterranean basin is a transitional biogeographical region for the distribution of the representatives of the main guilds of dung beetles; towards the south, Aphodiinae (dung-dwellers) become scarce, whereas northwards Scarabaeinae (soil-diggers) progressively disappear. The number of species in local dung beetle assemblages is enhanced by this double faunistic contribution. Annual dung beetle assemblages were sampled in two sub-Mediterranean sites, which differed by 600 m in elevation, in order to determine the phenological dynamics related to the way of using dung (dung-dwellers/Aphodiinae vs. soil-diggers/Scarabaeinae and Geotrupinae). Aphodiids were active all year round, although they were affected by summer drought and, at high elevation, by the length of the cold season. This reduced activity was related to an impoverishment of Aphodiinae and to reduced temporal segregation between species. In contrast, soil-diggers were not active all year round and showed different species assemblages in the two sites. An extension of the activity period of these beetles was observed due to the occurrence of cold resistant species at high elevation. Our results suggested that the occurrence of soil-diggers seemingly did not affect the seasonality of dung-dwellers; their local abundance showed no negative correlation and, most importantly, phenological differences between dung-dwellers were always significantly higher than the seasonal differences between dwellers and diggers.  相似文献   

12.
过去几十年来暖春等异常气候事件发生的频次和强度显著增加, 使植物春季物候期发生了明显变化。但异常气候事件对植物春季物候积温需求的影响仍不清楚, 限制了对未来物候变化预测精度的提升。该研究利用西安植物园1963-2018年39种木本植物的展叶始期和相应气象数据, 首先根据3-4月平均气温划分了偏冷年、正常年和偏暖年, 对比了冷暖年相对于正常年的展叶始期变化。其次, 利用3种积温算法计算了各植物逐年的展叶始期积温需求, 比较了积温需求在冷暖年和正常年的差异。最后, 评估了传统积温模型在模拟偏冷或偏暖年展叶始期时的误差。结果表明, 所有植物的展叶始期在偏暖年比正常年平均早8.6天, 而在偏冷年平均晚8.2天。在偏暖年, 大多数物种展叶始期的积温需求(以5 ℃为阈值, 平均257.5度日)显著高于正常年(平均195.1度日); 在偏冷年的积温需求(平均168.0度日)低于正常年, 但在统计上差异不显著。就不同类群而言, 古老类群相对于年轻类群在偏冷年的推迟天数更多, 积温需求变化较小, 但在偏暖年无显著差异。不同生活型间物候与积温需求变化也无显著差异。造成偏暖年积温需求增加的可能原因是偏暖年冬季气温较高, 导致植物受到的冷激程度减轻, 从而抑制了后续的展叶。在正常年, 积温模型模拟木本植物展叶始期的平均误差仅为0.4-1.9天。在偏暖年和偏冷年, 模拟值分别比观测值平均早4.1天和晚3.0天。因此在预测未来物候变化时, 需要考虑气候波动条件下的积温需求变化。  相似文献   

13.
Phlebotomus duboscqi is the principle vector of Leishmania major, the causative agent of cutaneous leishmaniasis (CL), in West Africa and is the suspected vector in Mali. Although found throughout the country the seasonality and infection prevalence of P. duboscqi has not been established in Mali. We conducted a three year study in two neighboring villages, Kemena and Sougoula, in Central Mali, an area with a leishmanin skin test positivity of up to 45%. During the first year, we evaluated the overall diversity of sand flies. Of 18,595 flies collected, 12,952 (69%) belonged to 12 species of Sergentomyia and 5,643 (31%) to two species of the genus Phlebotomus, P. duboscqi and P. rodhaini. Of those, P. duboscqi was the most abundant, representing 99% of the collected Phlebotomus species. P. duboscqi was the primary sand fly collected inside dwellings, mostly by resting site collection. The seasonality and infection prevalence of P. duboscqi was monitored over two consecutive years. P. dubsocqi were collected throughout the year. Using a quasi-Poisson model we observed a significant annual (year 1 to year 2), seasonal (monthly) and village effect (Kemena versus Sougoula) on the number of collected P. duboscqi. The significant seasonal effect of the quasi-Poisson model reflects two seasonal collection peaks in May-July and October-November. The infection status of pooled P. duboscqi females was determined by PCR. The infection prevalence of pooled females, estimated using the maximum likelihood estimate of prevalence, was 2.7% in Kemena and Sougoula. Based on the PCR product size, L. major was identified as the only species found in flies from the two villages. This was confirmed by sequence alignment of a subset of PCR products from infected flies to known Leishmania species, incriminating P. duboscqi as the vector of CL in Mali.  相似文献   

14.
云南元江干热河谷木本植物的物候   总被引:2,自引:0,他引:2  
在中国西南干热河谷的典型地段——元江干热河谷,连续3年观测了32种木本植物的枝条生长、叶片动态、花期、果期和果实类型。这些植物的枝条生长方式可以分为连续生长、枝条枯死、陡长和间歇生长4个类型。其中连续生长型占优势,包括13种植物,它们的枝条在雨季连续不断伸长。9种植物雨季的枝条伸长与连续生长型的相似,但它们顶部的枝条在旱季末期出现枯死现象。6种植物属于陡长型,在2周内完成抽枝,且一年只抽一次枝。4种植物属于间歇生长型,枝条在雨季来临后伸长一段时间,然后生长停滞,过一段时间后再接着伸长。从叶片物候类型看,元江干热河谷植被以落叶植物占优势。落叶植物中冷凉旱季(11月~2月)落叶植物占优势(19种),而干热旱季(3—4月)落叶植物很少(4种)。除红花柴(Indigofera pulchella)和狭叶山黄麻(Trema angustifolia)从雨季中期开始脱落叶片外,其它30种植物从雨季末期开始脱落叶片,落叶期至少延续3个月以上。常绿植物脱落近1/3~1/2的当年生叶片。共有6种植物能在旱季末期长出新叶。常绿植物的叶面积、单个枝条上的总叶面积和枝条承载(总叶面积/枝条长度)比落叶植物小。虽然一年四季都有不同植物开花和结果,但多数植物(29种,占观测树种的91%)的花期集中在旱季和雨季初期,而果实(种子)成熟期从雨季末期延续到旱季末期和下个雨季初期。果实多为核果。  相似文献   

15.
Soil resource availability varies across seasons and soil layers. Both plant phenology, i.e. the sequence of growth and developmental changes along the year, and plant life form, i.e. the life cycle, distribution of roots, and longevity of leaves, determine the ability to use resources. The phenological heterogeneity within and among life forms of a single community may reveal key features of community structure, such as temporal niche segregation within life forms or convergence of phenological and life form patterns. We described the phenological patterns of most species of a Patagonian steppe composed of four life forms: perennial grasses, shrubs, annual herbs, and perennial herbs. By applying standard multivariate analysis techniques, we classified the species into three phenological groups and analysed the variation among groups and life forms. One phenological group, composed exclusively by grasses, had higher autumn-winter phenological activity than the other two groups. The non-grass groups differed in the date of beginning of vegetative growth and ending of the reproductive growth, one of the groups being earlier than the other. However, the three groups coincided at the phenophase of floral buds and open flowers, which occurred around the time of the maximum rate of phenological change and maximum fraction of photosynthetically active radiation being intercepted by the entire community. Phenological groups and life forms only partially overlapped: grasses and annual herbs belonged to individual phenological groups, whereas shrubs and perennial herbs spread across two groups. Thus, some life forms of the community were strictly related to a phenological behaviour, whereas other showed high temporal niche segregation. Simultaneously, diverse life forms converged into similar phenological patterns.  相似文献   

16.
沈阳城市森林常见树种的物候特征   总被引:2,自引:0,他引:2  
胡健波  徐文铎  陈玮  何兴元  闻华 《生态学杂志》2006,25(12):1455-1459
城市绿化树种的物候配置是城市园林的一个重要组成部分。本文以沈阳城市森林常见树种为对象,利用6年的物候观测数据,绘出了28种主要乔灌木的物候谱。分析各物候现象之间关系,将其划分成4大组:萌动展叶现象组、叶变色现象组、落叶现象组和花果现象组;并根据叶变色和开花早晚对其进行聚类分组,为城市森林树种选择、树种组成和效益评价,提供科学依据。  相似文献   

17.
Variation in evergreen and deciduous species leaf phenology in Assam, India   总被引:1,自引:0,他引:1  
In the present study phenological activities such as leaf and shoot growth, leaf pool size and leaf fall were observed for 3 years (March 2007–March 2010) in 19 tree species (13 evergreen and 6 deciduous species) in a wet tropical forest in Assam, India. The study area receives total annual average rainfall of 2,318 mm of which most rain fall (>70 %) occurs during June–September. Both the plant groups varied significantly on most of the shoot and leaf phenology parameters. In general, growth in deciduous species initiated before the evergreen species and showed a rapid shoot growth, leaf recruitment and leaf expansion compared to evergreen species. Leaf recruitment period was significantly different between evergreen (4.2 months) and deciduous species (6.8 months). Shoot elongation rate was also significantly different for evergreen and deciduous species (0.09 vs. 0.14 cm day?1 shoot?1). Leaf number per shoot was greater for deciduous species than for evergreen species (34 vs. 16 leaves). The average leaf life span of evergreen species (328 ± 32 days) was significantly greater than that of deciduous species (205 ± 16 days). The leaf fall in deciduous species was concentrated during the winter season (Nov–Feb), whereas evergreens retained their leaves until the next growing season. Although the climate of the study area supports evergreen forests, the strategies of the deciduous species such as faster leaf recruitment rate, longer leaf recruitment time, faster shoot elongation rate during favorable growing season and short leaf life span perhaps allows them to coexist with evergreen species that have the liberty to photosynthesize round the year. Variations in phenological strategies perhaps help to reduce the competition among evergreen and deciduous species for resources in these forests and enable the coexistence of both the groups.  相似文献   

18.
Plant phenological studies in the Mediterranean have traditionally focused on the limits that summer drought exerts over plant seasonal behaviour. However, Mediterranean areas also occur across extensive regions under cooler climates. Here, we analyse phenological data of Mediterranean woody species from winter-cold sites to address the following questions: what is the most limiting period of the year for phenological development? How, and how synchronously, do different phenophases adjust to the bimodal limitation of summer drought and winter cold? How ample is the suit of phenological strategies that are successful for Mediterranean phanaerophytes from cool areas?  相似文献   

19.
Yeasts from crops of Drosophilidae (154 flies belonging to 22 species) of Lamto savannas (Ivory Coast) were studied. 50 yeast strains (belonging to 19 species) were isolated and studied. The most frequently isolated yeasts wereHanseniaspora andPichia membranaefaciens s.l.; these yeasts ferment and assimilate few of the carbon compounds. Some crops contained until 100 000 yeast cells. In 25% of the flies, these yeasts belonged to several different species.  相似文献   

20.
Fire is an ancient ecological factor influencing the Mediterranean vegetation of southern France. The study was carried out on three areas to determine the phenological behaviour of plants with regard to fire. First we studied the flowering responses of perennials in relation to the time since fire: in a Quercus coccifera garrigue most species flower during the year following burning. In comparing species by species between burned and unburned areas most species did not show major differences in the phenological stages. However, fire did increase the number of inflorescences of grasses. A phenological synthesis showed that differences at the community level existed for the flowering stages between the burned areas and the unburned control sites during the first and second years following fire. The growth of some woody species was also studied; the elongation and growth of the plants were biggest during the first or second year after fire. The lack of differences in phenological response between burned and unburned plants may be an adaptive trait to fire.  相似文献   

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