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1.
陆生脊椎动物生态学研究的过去、现在和将来(前苏联科学院动物进化形态学与生态学研究所,莫斯科)Past,PresentandFutureofEcologicalResearchonTerrcstrialVctebratcs¥.(InstituteofAnimalEvolutionaryMorphologyandEcology,theFormerAcademyofSclencesofSovietUnion).ChineseJournalofEcology,1993,12(4):66-71。Thispaperdescribesthemainstages,directionsanditemsofecologicalresearchintheformersovietU-nion.EcologicalresearchinthecountrywasrestrodedbymanysuUectiveandoUectivefactorsandstilllagsbehindtheworldlevelinmanyaspectssuchaspopulationdynamicstheory,communityresearch,eco-  相似文献   

2.
空气污染对植物病虫害的影响吴亚,金翠霞(江苏省农科院植物保护研究所,南京210014)EffectsofAtmospbericPollutiononPlantDiseasesandPests¥WuYa;JinCuixia(InstituteofPlantPro-tection,JiangsuAcademyofAgriculturalSciences,Nanjing210014).ChineseJournalofEcology,1993,12(6):49-53.Thispapersummarizestheeffectsofmainatmosphericpollutants,suchasO_3,SO_2,fluorides,acidrainetc.onplantpathogenicmicroorganisms;theeffectsofairpollutionontheoccuranceandinfestationofphytophagusinsects,andtheinfluencesofgreenhouseeffectofCO_2ontheoutbreakofpests。Keywords:atmospheri  相似文献   

3.
生态农业:一种思想体系传播的实证分析   总被引:1,自引:0,他引:1  
李季 《生态学杂志》1993,12(3):63-67
生态农业:一种思想体系传播的实证分析李季(北京农业大学100094)EcologicalAgriculture:APositiveAnalysisoftheSpreadingofItsIdeology¥.LiJi(DepartmentofLandResources.BeijingAgriculturalUniversity,Beijing100094).ChineseJournalofEcology,1993,12(3):63-67.ThispaperreviewstheoverallhistoriesofecologicalagricultureinChinainthelast10years,includingitsfeatures,researchesandpractices,andgivessomediscussions,conclusionsandperspectivesofitsdevelop-mentaltrend.Keywords:ecologicalagriculture,ecosystem,eco-economics.我国的生态农业从兴起到现在已十余载,其发展之迅猛无论在理论上还是实践上,  相似文献   

4.
加强农业生态学的实验研究   总被引:1,自引:0,他引:1  
加强农业生态学的实验研究闻大中(中国科学院沈阳应用生态研究所,110015)StrengtheningExperixnentalResearcbesofAgroecology¥WenDazhong(InstituteofAppliedEcology,A-cadelniaSinica,Shenyang110015).ChineseJournalofEcology,1993,12(2):8-10.Thispaperdescribesthreebasicresearchapproachesinecologicalstudies,andemphasizesontheimpor-tanceofexperimentalapproach,whichshouldbeconsideredasabasicresearchapproachofagroecology.Hoviever,currentexperimentalstudiesofagroecologyinChinaneedstobestrengthened,andmoreef-fortsareneededtoimproveexperimentalresearchfaci  相似文献   

5.
持续农业与中国的生态农业   总被引:6,自引:0,他引:6  
持续农业与中国的生态农业李萍萍,章熙谷(南京农业大学农学系,210014)SustainableAgricultureandChina’sEcologicalAgriculture¥.LiPingping;ZhangXigu(NanjingAgricul-turalUniversity,210014).ChineseJournaJofEcolegy,1993,12(2):16-18.Thebackground,conceptandcharacteristicsofsustainableagriculturearediscussed,anditssimilaritiesanddifferencestoChina’secologicalagriculturearedescribed.It’sconsideredthatChina’secologicalagri-cultureisaconcretereflectionofsustainableagricultureandasuccessfulmodelforagriculturaldevelop-ment.Keywords:sustainableagricult  相似文献   

6.
我国海洋浮游幼虫的生态研究展望   总被引:2,自引:0,他引:2  
郑重 《生态学杂志》1993,12(1):35-36
我国海洋浮游幼虫的生态研究展望郑重(厦门大学海洋系,361005)EcologicalResearchProspectiveofMarinePlanktonicLarvainChina¥ZhengZhong(DepartmentofOceanography,XiamenUniversity,361005).ChineseJournalofEcology,1993,12(1):35-36。ThispaperdealswiththeprospectiveofecologicalresearchonmarineplanktoniclarvainChina,andcon-sistsofthefollowingthreeparts:naturalecology,experimentalecologyandappliedecology.Ineachpartabriefaccountoffutureresearchproblemsisgiven.Theauthorisoftheopinionthatmarineecosys-temshouldbethefocusoffutureresearch,inordertomake  相似文献   

7.
西藏生态农业探讨刘明允,王德亭(西藏农牧学院,八一850400)EcologicalAgricultureinTibet¥.LiuMingyun;Wangbeting(TibeiCollegeofAgricldturalandAnimalHusbondry,850400).ChineseJournalofEcology,1993,12(3):73-75.Inthispaper,fourbasicprinciplesconcerningtheconservationofecologicalagricuItureinTibetareputforwardandsomecharacteristicsandoperatedagrotechniquesofTibe'secologicalagricuIturearesumma-rized.Basedonthese,agro-ecosystemsinTibetareclassifiedintotwogroups,i.e.,temperate-humidforestry-agriculture·animalhusbandrycombinedecosystemandarid-  相似文献   

8.
李季 《生态学杂志》1993,12(2):23-24
农业生态系统的人类生态学分析模式探讨李季(北京农业大学农业生态环境科学系,100094)AnAnalyticalModelofAgroecosystemfromHumanEcologyPerspective¥.LiJi(DepartmentofEcologyandEnvironmentalSciences,BeijingAgriculturalUniversity100094).ChineseJournalofEcology,1993,12(2):23-24.Basedontheanalysisofourcurrentagro-ecologicalrcsearch,anewanalyticalmodelofagro-ecosystemkestablishedandthecontentsofitsresearcharerestructured.Theaimoftheseistoprovideamodelforthedevelopmentofregionalagriculture,whichcannotonlyexpandthecurrentrelatedtheoriesandmethodologies,but  相似文献   

9.
生态位理论及其在森林生态学研究中的应用   总被引:43,自引:4,他引:43  
生态位理论及其在森林生态学研究中的应用朱春全(中国林业科学研究院林业研究所,北京100091)NichcTheoryanditsApplicationinForestEcology¥.ZhuChunquan(InslituteofForestry,ChineseAcademyofForestrySciences,Beijing100091),ChineseJournalofEcology,1993,12(4):41-46.Thedevelopmentofnichetheoryanditsapplicationinforestecologicalstudyarereviewedinthispaper.Itispointedoutthatthefunctionalactionofplantunitwasnotinvolvedinpreviousnicheconcepts,Theparticularitiesofnicheofplantunitarediscussedandanewmethodisdevelopedtodetermineitwithpho-tosyntheticproductionasafunct  相似文献   

10.
真桑钝绥螨对柑桔全爪螨不同螨态的选择性蒲天胜,曾涛,韦德卫(广西农科院植物保护研究所,南宁530007)SelectivePredacityofAmblyseiusmakuwatoVariousMiteFormsofPananychuscitri¥PuTiansheng;ZengTao;WeiDewei(InstituteofPlantProlection,GuangxiAcademyofAgriculturalSciences).ChineseJour-nalofEcology,1993,12(1):33-34。TheselectivepredacityoffemaleadultofA.makuwatocitrusmitesissimulatedincomparisonwithspeciesofAnicholsi.A.makuwashowsanegativepreferencetotheadultofP.citri,butA.nicholsishowsnoselectivityandswitching.Inmulti-formcoexistentsystemofmites,thefunctionalres  相似文献   

11.
The distribution of gastro-intestinal nematodes collected from lambs was investigated using the Taylor's power law index of aggregation beta, which is known to be independent of the mean population size. For 12 out of the 15 nematode species investigated the estimate of beta was not significantly different from 2.0. For these species a logarithmic transformation would stabilize the variance of the distributions prior to further statistical analysis. The remaining species had values of beta which were significantly lower than 2.0. For these species a variance-stabilizing transformation is given by z = x1-beta/2.  相似文献   

12.
This paper describes the spatial and temporal distribution of Anopheles gambiae s.l. Giles in two Tanzanian villages based on data collected from a five-month intensive mosquito sampling programme and analysed using Taylor's power law. The degree of spatial aggregation of female A. gambiae in each village was similar to its corresponding temporal aggregation, indicating that in designing sampling routines for estimating the abundance of mosquitoes, sampling effort should be allocated equally to houses (spatial) and nights (temporal). The analysis also showed that for a given amount of sampling effort, estimates of village-level mosquito abundance are more precise when sampling is carried out in randomly selected houses, than when the same houses are used on each sampling occasion. Also, the precision of estimating parous rates does not depend on whether mosquito sampling is carried out in the same or a random selection of houses. The implications of these findings for designing sampling routines for entomological evaluation of vector control trials are discussed.  相似文献   

13.
The study proposes methodological developments to optimize sampling strategy of resting cysts of Alexandrium catenella to estimate their abundance with a predefined error. This work also aims to provide information on spatial distribution of resting cysts in sediments. The distribution mode of A. catenella resting cysts related to the abundance variability was studied through sediment cores sampling on four different spatial scales and using Ludox CLX gradient density method. The quantification method underestimates by a factor of 2 the resting cysts abundance in one gram of sediment. Application of Taylor's power law allowed us to define a compromise between sampling effort and abundance estimation error. In the case of A. catenella resting cysts from Thau lagoon, the optimal sampling strategy consists of sampling 10 stations on a surface of 2 km2 for a given coefficient of variability (C) of 15%, sampling 3 sediment cores at each station (C = 30%) and counting only one replicate by core (C = 18%). Results related to the application of Taylor's power law are closely dependent on resting cyst density and aggregation in a given sediment. In our area, A. catenella resting cysts are mainly observed in the upper 3 cm of sediment. Horizontally, their heterogeneity is lower on 10 cm2 surface and tends to stabilize itself beyond a surface of 10 m2. Each author has to carry out this pre-sampling effort for his own resting cysts-forming species, in his own area, in order to increase accuracy of resting cyst mapping.  相似文献   

14.
Using ecological laws, or rules, is a useful strategy for epidemiological observations. The application of Taylor's power law to epidemiology and evolutionary ecology of parasites is exemplified here. Taylor's power law takes the form of s2=amb, where s2 is the variance in population abundance, m is the mean abundance of the population, a represents a constant parameter and b represents an index of spatial heterogeneity. Although Taylor's power law reflects the aggregation of parasite (or pathogen) individuals among host population, the values of b could reflect regulation processes in host-parasite systems. Illustrations are given showing how b value is linked to various epidemiological situations: pathogen emergence, the impact of vaccination or the level of host immune defence.  相似文献   

15.
The numbers of greenbugs, Schizaphis graminum (Rondani), and bird cherry-oat aphids, Rhopalosiphum padi L., per wheat tiller (stem) were estimated in 189 production winter wheat (Triticum aestivum L.) fields located throughout Oklahoma. Taylor's power law regressions were calculated from these data and used to construct fixed precision sequential sampling schemes for each species. An evaluation data set was constructed from 240 samples taken during three growing seasons from winter wheat fields at four locations in Oklahoma. Wheat cultivar and growth stage were recorded for each field on the day of sampling. Taylor's power law parameters for evaluation fields differed significantly for both species among growing seasons, locations, and plant growth stages. Median precision achieved using the fixed precision sequential sampling schemes for each species departed <20% from expected precision over the range population intensity in the evaluation data. For the 10% of samples with greatest deviation between observed and expected precision, observed precision was 13.8-81.8% greater than that expected precision depending on aphid species and population intensity. For the greenbug, the distribution of the percentage deviation between observed and expected precision was positively skewed, so that the sampling scheme tended to over-predict precision. For the bird cherry-oat aphid, the distribution was more symmetric. Even though precision observed using the sampling schemes frequently varied from expected precision, because of the inevitable consequence of sampling error and environmental variation, the sampling schemes yielded median observed precision levels close to expected precision levels over a broad range of population intensity.  相似文献   

16.
1991年4月—7月在河北省北京农业大学曲周试验站的棉花地进行苗期棉蚜(Aphisgossypii)的田间抽样调查,共收集到24组抽样数据。用泰勒幂法则对数据进行拟合,得到棉花苗期棉蚜为聚集分布。利用每样方(株)虫口不超过数阈值T(分别为0,1,2…9,10,15,20,30)头蚜虫的植株比例(PT)与种群密度(m,头/株)的关系,拟合经验关系式ln(m)=a十bln[-ln(PT)],通过对不同数阈值T的回归决定系数(r2)、种群的回归估计方差(Var(m))和抽样精度(用d估计)等进行综合分析,结果表明该蚜虫在数阈值T为15时,回归估计方差最小,回归决定系数和d值最大,因而T=15为该蚜虫的理想数阈值;而小的T值尤其是T为O时,由于产生太大的回归估计方差,很小的回归决定系数和d值即抽样的精度极低,因而不宜在实际中应用于棉蚜的二项式抽样设计。  相似文献   

17.
甘蓝和白菜上桃蚜种群的空间格局及其时序动态   总被引:12,自引:0,他引:12  
刘树生  汪信庚 《昆虫学报》1996,39(2):158-165
1999-1992年在杭州郊区菜区连续调查了10茬结球甘蓝、19茬白菜上桃蚜Myzus Persicae种群的分布图式。利用这些数据计算出多项空间聚集指标,分析了各项指标与密度的相关性,然后选择受密度影响较小的负二项分布的K值,描述了种群的空间格局及其时序动态。两类蔬菜上桃蚜种群全年呈聚集分布;但聚集强度变化有明显的季节规律。一年中5月和11月前后有两个明显的扩散高峰;在蚜虫迁离本田的6~7月和重新迁入本田的9-10月前后则有两个聚集高峰。在一季作物上的聚集强度随时间的变化过程因季节而异,春夏季为高一低一高,秋冬季从高往低呈持续下降,而冬春季则呈上下随机波动趋势,文中最后对桃蚜种群空间图式及其时序动态特征的成因,尤其是气温和植株营养条件变化的影响进行了讨论。  相似文献   

18.
The most common lepidopterous borers attacking maize and/or the wild host Pennisetum purpureum in the forest zone of Cameroon are the noctuids Busseola fusca (Fuller), Sesamia calamistis (Hampson) and Poeonoma serrata (Hampson), the pyralids Eldana saccharina (Walker) and Mussidia nigrivenella (Ragonot), and Cryptophlebia leucotreta (Tortricidae). The within-plant distribution on maize and elephant grass was studied for the predominant species B. fusca , and on maize only for E. saccharina to determine the basic sampling unit. On both plant species, B. fusca showed a strong oviposition preference for young plant parts. By contrast, E. saccharina larvae and pupae on maize were only found on older plant parts indicating that it does not oviposit on young plants. No part of the plant strata appeared to be a stable sampling unit and it is recommended to carry out whole plant or whole tiller sampling for maize and grass, respectively. For the development of sampling plans, dispersion was described for all species using Taylor's power law and a non-linear model which gives the relationship between the proportion of infested plants [ P ( I )] and mean density ( m ). Busseola fusca egg batches as well as diapausing larvae and pupae on maize showed a random distribution whereas all the other cases were aggregated, with B. fusca egg batches on elephant grass exhibiting the lowest and M. nigrivenella on maize the highest aggregation. Optimal sample size/mean density curves were developed for groups of insects with low and high aggregation.  相似文献   

19.
Abstract  Based on field population sampling of Aphis gossypii on cotton seedlings in Quzhou Experiment Station of China Agricultural University in Hebei Province in 1991, we obtained a data set consisting of 24 estimates of mean aphid density ( m , number of aphids per plant), variance (s2) and the proportion of plants (PT) with no more than T aphids (T=0, 1, 2,…, 8, 10, 15, 20, respectively and defined as tally threshold). Taylor's power law fitted the data well (r2= 0. 958). The resulting slope (1. 515) was significantly greater than 1, indicating that the spatial distribution of this aphid was in aggregated pattern. An empirical relationship between m and Pr was developed for each T value using the parameters from the linear regression In( m )= a +bln[- ln( PT )}]. The importance of the T values in reduction of sampling errors and their application to binomial sampling plans are discussed. Small T values, particularly aphid-free plant (T = 0, conventional binomial sample), could lead to spurious estimates of m from PT . A value of T from 10 to 15 was recommended to develop binomial sampling plans for the aphids on cotton seedlings because of the relatively small sampling errors.  相似文献   

20.
The horizontal distributions of infective larvae on pasture grazed by sheep have been investigated. Using Taylor's Power Law it was found that larvae had a more aggregated distribution in September than August, the Law index of aggregation being 1.97 and 1.89 for the 2 months, respectively. However, at each time the degree of aggregation remained fairly constant for a range of spacings between points from 5 to 30 m. These results suggest that Taylor's Power Law could be used as a basis for devising an efficient pasture sampling strategy. More data are required, however, to determine the extent to which aggregation of the larvae varies with time of the year.  相似文献   

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