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1.
稻纵卷叶螟对杂交水稻及常规水稻的生态反应   总被引:6,自引:0,他引:6  
钱希 《生态学杂志》1993,12(6):21-24
稻纵卷叶螟对杂交水稻及常规水稻的生态反应钱希(国营黄海农场,江苏省响水县224624)EcologiealResponsesofRiceCasewormtoHybridRicesandTraditionalRices¥QianXi(TheStateFarmofYellowSea,XiangshuiCounty,Jiangsu,Province224624).ChineseJournalofEcology,1993,12(6):21-24.Tostudytheeffectofricecultivarsontheoviposition,emergence,wormdevelopmentandnaturalenemvparasitionofcasewormandlossescausedbythepest,observationshavebeenmadeon16ricecultivarsinHuanghaiStateFarminNorthernJiangsuprovince,wherecasewormgraduallybecomemoreandmorevi-olentsincethechangesincultiva  相似文献   

2.
90年代农村发展与农业生态研究彭廷柏(中国科学院长沙农业现代化研究所,410125)RuralDevelopmentandAgro-ecologicalResearchin1990s¥.PengTingbai(ChangshaInstituteofAgri-culturalModernization,AcademiaSinica,410125).ChineseJournalofEcolegy,1993,12(2):2-3.InordertoapproachtherelatedproblemsofChina’sagro-ecologicalresearchin1990s,thispaperana-lyzedthenewtrendsofstructuralchangesinruraleconomyandagro-ecology.underconditionofsocialistmarketeconomyexpoundedsomeviewpointsonthecoordinativedevelopmentofagro-ecologyandagro-economy,thestrengtheningofabsorbi  相似文献   

3.
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   

4.
沈阳水资源保护与水质管理李秀鸿(沈阳环境科学研究所,110005)WaterResourceConscrvancyandWaterQualityControlinShenyang¥LiXiouhong(ShenyangInstituteofEnvironmentalscieilce,110005).(ChineseJournalofEcology,1993,12(5):45-48。Theoverallandlongtermimpactsofwaterresourceshortageandwaterpollutiononeconomicdevelop-ment,humanlifeandecologicalenvironmentinShenyangarediscussedinthispaper.Itispointedoutthatinordertosolvetheseproblems,areasonablecontrolpolicyandcorrespondingtechnologymustbeadoptedincombiningwiththedevelopmentandConservancyofexistin  相似文献   

5.
集约高产过程中土壤有机质动态初探   总被引:2,自引:0,他引:2  
集约高产过程中土壤有机质动态初探崔玉亭,韩纯儒(北京农业大学,100094)DynamicsofSoilOrganicMatter(SOM)intheProcessofAgriculturalIntensification¥.CuiYuting;HanChunru(BeijingAgriculturalUniversity,100094).ChineseJournalofEcology,1993,12(2):37—38.Inthispaper,thebalanceofsoilorganicmatter(SOM)intheprocessofagriculturalintensificationinChangzhouregionisstudiedandamedium-andlong-termpredictionofitsdynamicsismade。There-sultsshowthatduringthisprocess,thebalanceofSOMisgettingbetter,andafteramediumorlongpe-riod(e.g,10—20yeats),theSOMcontentcangett  相似文献   

6.
湖北省吨粮田的现状及其投肥效率分析孙先(华中农业大学,武汉430070)CurrentSituationandFertilizationEfficiencyofHighProductiveCroplandsinHubeiProvince¥SunXian-rong(CentralChinaAgricultureUniversity,Wuhan430070).ChineseJournalofEcologyl1993,12(2):55-56.Since1990,thedevelopmentofhighproductivecroplandhasbeenacceleratedandtheeffectofitsyieldandbenefitincreaseisveryobvious,But,whetherhighyieldandhighefficiencycanbesynchronizedde-servescloseattention,Inthisresearch,79highyieldcroppingpatternsareinvestigatedforthreeyearsinHubeiandtheirefficien  相似文献   

7.
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   

8.
薛玺  王永清 《植物研究》1994,14(4):424-433
本实验用普通小麦“中国春”和八种异细胞质“中国春”(Aegilops vavilovii)CS,(Ae.juvenalis)CS,(Ae.crassa)CS,(Ae.comosa)CS,(Ae.uniaristata)CS,(Ae.speltoides.M.)CS,(Ae.kotschyi)CS.(T.timopheevi)CS分别与八倍体小偃麦(Trititrigia 8x)“远中2”、“远中4  相似文献   

9.
浸润垄作稻田土壤生态系统的研究   总被引:7,自引:0,他引:7  
浸润垄作稻田土壤生态系统的研究魏朝富,高明,车福才,邓春(西南农业大学土化系重庆630716)AStudyonInfiltrated-RidgedPaddySoilEcosystem¥.WeiChaofu;GaoMing,CheFuchai;DengChun(SouthwestAgriculluralUniversity,).ChineseJournalofEcology,1993,12(3):26-30;Thispaperdealswichaninfiltrated-ridgedpaddysoilecosystemwhichisconstructedbyridgingandcon-tinuousfurrowinfiItratiOnirrigation,ComparingwithlevelinfiItratedpaddysoilecosystem,thisecosys-temhascoexistedgas-liquid,gas-solidandliquid-solidinterfaces,enlargessoilsurfaceby38%andincreasescuItivatedlayerby5-10cm.  相似文献   

10.
克隆哺乳动物的一些进展   总被引:5,自引:1,他引:4  
陈秀兰CHEN  Xiu-Lan 《遗传》1997,19(5):41-44
克隆哺乳动物的一些进展陈秀兰(中国科学院遗传研究所,北京100101)RecentProgresinMammalianCloningChenXiulan(InstituteofGenetics,ChineseAcademyofSciences,Bei...  相似文献   

11.
Abstract Macro-invertebrates, zooplankton and water quality variables were sampled at 33 wetlands near Perth, Western Australia, in January-February 1989. Wetlands were classified and ordinated using the invertebrate data. Correlations of environmental variables with the ordination were calculated and the importance of seasonality and geomorphology of the wetlands were investigated. The wetlands were also classified and ordinated using the chemical data. Analysis of variance was used to compare species richness, abundances of all invertebrates, macro-invertebrates, copepods and total phosphorus levels among groups. Six groups of wetlands were identified from the invertebrate data, two of which were outliers on the basis of very low pH and high salinity, respectively. The majority of the wetlands grouped on the basis of their degree of nutrient enrichment and colour. The analyses of chemical data gave similar groups. The coloured wetlands and least nutrient enriched non-coloured wetlands were identified as being closest to the probable state of wetlands prior to European settlement. The greatest numbers of rare species were found in wetlands from these two groups. Species richness was significantly higher in the moderately enriched wetlands than in any other group but decreased in the most enriched wetlands where abundances of invertebrates were highest. Changes in community composition among the groups of wetlands are discussed. The most highly nutrient enriched wetlands were dominated by cosmopolitan species with high abundances, whereas less enriched and coloured wetlands had species with more restricted distributions and lower abundances.  相似文献   

12.
How closely the vegetation of restored wetlands resembles that of comparable natural wetlands is a function of the probability of propagules of wetland species reaching reflooded wetlands and how similar environmental conditions in the restored wetland are those in the natural wetlands. Three years after reflooding, we examined the vegetation composition, water level fluctuations, soil organic carbon content, and soil bulk density as well as surface water pH, alkalinity, conductivity, and calcium and magnesium concentrations of 10 restored and 10 natural wetlands. In the restored wetlands, more species of submersed aquatics colonized than were found in natural wetlands, and they rapidly spread to form extensive beds that were larger than those found in natural wetlands. Emergent and wet meadow species in restored wetlands, however, were found in only sparse stands as were a variety of annuals. The vegetation of natural wetlands was predominantly large stands of emergent species. Fluctuations in water storage volume and basin surface area were similar for both restored and natural wetlands. The surface water in restored wetlands had higher pH and lower alkalinity, conductivity, and calcium and magnesium concentrations than that in natural wetlands. Soils of restored wetlands have a lower organic carbon content and higher bulk density than do those of natural wetlands. Our results suggest that for submersed aquatics, dispersal of propagules to restored wetlands is rapid and environmental conditions in restored wetlands are very suitable for their establishment. For other guilds of wetland species, e.g., sedges and other wet meadow species, dispersal to restored wetlands is likely much slower and may pose a serious problem for the re-establishment of these species in restored wetlands. Even if dispersal is not limiting, low surface organic carbon and high bulk density may prevent the establishment of these species in restored wetlands.  相似文献   

13.
The functional and structural attributes of algal assemblages were studied in 25 restored and 20 extant depressional wetlands in southern central Michigan. Environmental conditions and algal assemblages were compared between restored and extant wetlands and among habitats within wetlands. Restored marshes generally had lower shading by macrophytes, nutrient concentrations, and sediment organic matter. Relative biovolume of non-diatom algae was significantly different among plankton, macrophyte and sediment habitats in restored wetlands, but did not differ between macrophytes and sediments in extant wetlands. Species composition of diatom assemblages was not significantly different between plants and sediments in both restored and extant wetlands. The observed differences in non-diatom algae could not be attributed to any measured environmental variable; however, diatom assemblage differences between habitats increased with light irradiance. Differences in sediment diatom assemblages were observed between restored and extant wetlands and were related to differences in nutrients, pH, and canopy cover. Differences were also observed between epiphytic diatom assemblages in restored and extant wetlands and they were related to light and dissolved oxygen. In summary, differences in light and nutrient availability were the main environmental factors differentiating algal communities in wetlands.  相似文献   

14.
We analyzed data from Section 404 permits issued in California from January 1971 through November 1987 that involved impacts to wetlands and required compensatory mitigation (wetland creation, restoration, or preservation). The purpose of this study was to determine patterns and trends in permitting activity and to document cumulative effects of associated management decisions on the California wetland resource. The 324 permits examined documented that 387 compensatory wetlands (1255.9 ha) were required as mitigation for impacts to 368 wetlands (1176.3 ha). The utility of the data on wetland area was limited, however, since 38.0% of the impacted wetlands and 41.6% of the compensatory wetlands lacked acreage data. The wetland type most frequently impacted (37.8% of impacted wetlands) and used in compensation (38.2% of compensatory wetlands) was palustrine forested wetlands. Estuarine intertidal emergent wetlands had the most area impacted (52.3%) and compensated (62.5%). The majority of the wetlands were small (less than or equal to 4.0 ha in size). Wildlife habitat was the most frequently listed function of impacted wetlands (90.7% of the permits) and objective of compensatory wetlands (83.3%). Endangered species were listed as affected in 20.4% of impacted and 21.0% of compensatory projects. The number of permits requiring compensatory mitigation and the number of impacted and compensatory wetlands increased from 1971 to 1986.Documentation of the details of Section 404 permit decisions was inadequate for the permits we examined. Area information and specific locations of impacted and compensatory wetlands were lacking or of poor quality. Follow-up information was also inadequate. For example, project completion dates were specified in the permit for only 2.2% of compensatory wetlands. Furthermore, less than one-third (31.5%) of the permits required the compensatory wetland to be monitored by at least one site visit. We recommend improved documentation, regular reporting, and increased monitoring for better evaluation of the Section 404 permitting system.  相似文献   

15.
节肢动物是湿地生物多样性的重要组分,在维持湿地生态功能,指示湿地环境变化中发挥重要作用。在2020年7月对黑龙江三江国家级自然保护区沼泽湿地的23个采样点进行节肢动物样品采集,运用统计方法分析人类活动干扰对湿地节肢动物数量、群落组成、多样性的影响以及节肢动物对人类活动干扰的指示作用。共采集到节肢动物10目47科1825只,主要以双翅目和半翅目昆虫为主。自然湿地节肢动物的多度是干扰湿地的4.27倍;生物多样性指数在不同湿地类型之间存在一定差异,节肢动物的物种丰富度在自然湿地显著高于干扰湿地(P<0.05),而Pielou均匀度指数在干扰湿地显著高于自然湿地(P<0.05)。人类活动干扰对湿地节肢动物群落组成影响显著,聚类和非度量多纬尺度排序(NMDS)显示,两种湿地类型节肢动物群落结构相似性较低。指示值法分析显示,自然湿地的指示类群为叶甲科、蚁形甲科、叶蝉科、蚜科、盲蝽科、摇蚊科以及姬蜂总科,干扰湿地未发现指示类群。综上所述,湿地节肢动物对人类活动干扰响应十分敏感,可以作为指示湿地健康状况的关键生物类群。  相似文献   

16.
In southern Sweden, many wetlands have been constructed, and maintaining or increasing biological diversity is often included in the aims. Some wetlands are constructed near human settlements, thus raising the problem of wetlands being associated with mosquitoes (Diptera: Culicidae). Increased biodiversity (including mosquito diversity) is considered desirable, whereas mosquito nuisance from a human point of view is not. Adult mosquito abundance, diversity and species assemblages of constructed wetlands were compared to natural wetlands. The potential of constructed wetlands for mosquito nuisance and transmission of mosquito-borne viruses was evaluated. The study areas included five constructed and four natural wetlands. Mosquito abundance and species richness were higher in the natural than in the constructed wetlands, and showed a positive correlation with wetland size. Mosquito species assemblages formed three clusters, which were not explained by origin, size and water permanence of wetlands. In a redundancy analysis, however, mosquito faunas showed significant relationships with these variables, and size and origin of wetlands were most important. Major nuisance species (multivoltine species feeding on mammals and laying eggs on soil) were found in all wetlands, although in relatively low numbers. Risk assessment for Sindbis virus transmission showed moderate risk for two constructed wetlands near human settlements. It is concluded that small size of constructed wetlands has the advantage of low mosquito numbers from a human point of view. The use of functional groups is recommended as a tool for presenting mosquito data to the public, and for helping communication between scientists and administrative decision makers.  相似文献   

17.
Numerous efforts have been made in West Virginia to construct and restore compensatory wetlands as mitigation for natural wetlands destroyed through highway development, timbering, mining, and other human activities. Because such little effort has been made to evaluate these wetlands, there is a need to evaluate the success of these systems. The objective of this study was to determine if mitigation wetlands in West Virginia were adequately supporting ecological communities relative to naturally occurring reference wetlands and to attribute specific characteristics in wetland habitat with trends in wildlife abundance across wetlands. Specifically, avian and anuran communities, as well as habitat quality for eight wetland-dependent wildlife species were evaluated. To supplement this evaluation, vegetation and invertebrate communities also were assessed. Wetland ranks were assigned based on several parameters including richness, abundance, diversity, density, and biomass, depending on which taxa was being analyzed. Mitigation wetlands consistently scored better ranks than reference wetlands across all communities analyzed. Canonical correspondence analysis revealed no correlations between environmental variables and community data. However, trends relating wetland habitat characteristics to community structure were observed. These data stress the need to maintain specific habitat characteristics in mitigated wetlands that are compatible with wildlife colonization and proliferation.  相似文献   

18.
Physicochemical attributes were measured and aquatic macroinvertebrates were collected from six wetlands near Perth, Western Australia at three weekly intervals over a 13 month period from August 1988 to September 1989. The six wetlands encompassed a range of depths, pH, concuctivities, nutrient concentrations and colours. Temporal changes in the macroinvertebrate communities appeared to be related to seasonal changes in the physical and chemical characteristics of the wetlands. Community composition differed more between the less enriched wetlands then the higly enriched wetlands where communities were generally similar. High species richness was associated with seasonal drying. High macro invertebrate abundance appeared to be associated with the presence of either green algal or cyanobacterial blooms in the enriched wetlands. The highest macroinvertebrate biomass was recorded in wetlands with both cyanobacterial blooms and abundant macrophytes present.  相似文献   

19.
Many wetlands have been constructed in West Virginia as mitigation for a variety of human disturbances, but no comprehensive evaluation on their success has been conducted. Macroinvertebrates are extremely valuable components of functioning wetland ecosystems. As such, benthic and water column invertebrate communities were chosen as surrogates for wetland function in the evaluation of 11 mitigation and 4 reference wetlands in West Virginia. Mitigation wetlands ranged in age from 4 to 21 years old. Overall familial richness, diversity, density and biomass were similar between mitigation and reference wetlands (p > 0.05). Within open water habitats, total benthic invertebrate density was higher in reference wetlands, but mass of common taxa from water column samples was higher in mitigation wetlands (p < 0.05) Planorbidae density from benthic samples in emergent habitats was higher in reference than mitigated wetlands. Benthic Oligochaeta density was higher across open water habitats in mitigation wetlands. All other benthic taxa were similar between wetland types. Among the most common water column orders, Isopoda density was higher in reference wetlands, but Physidae density was higher in mitigation wetlands. Within mitigation wetlands, emergent areas contained higher richness and diversity than open areas. These data indicate that mitigation and reference wetlands generally support similar invertebrate assemblages, especially among benthic populations. The few observed differences are likely attributable to differences in vegetative community composition and structure. Mitigation wetlands currently support abundant and productive invertebrate communities, and as such, provide quality habitat for wetland dependent wildlife species, especially waterbirds and anurans.  相似文献   

20.
A comparison of created and natural wetlands in Pennsylvania,USA   总被引:7,自引:0,他引:7  
Recent research suggests that created wetlands do not look, or function, like the natural systems they are intended to replace. Proper planning, construction, and the introduction of appropriate biotic material should initiate natural processes which continue indefinitely in a successful wetland creation project, with minimal human input. To determine if differences existed between created and natural wetlands, we compared soil matrix chroma, organic matter content, rock fragment content, bulk density, particle size distribution, vegetation species richness, total plant cover, and average wetland indicator status in created (n = 12) and natural (n = 14)wetlands in Pennsylvania (USA). Created wetlands ranged in age from two to 18 years. Soils in created wetlands had less organic matter content, greater bulk densities, higher matrix chroma, and more rock fragments than reference wetlands. Soils in reference wetlands had clay loam textures with high silt content, while sandy clay loam textures predominated in the created sites. Vegetation species richness and total cover were both greater in natural reference wetlands. Vegetation in created wetlands included a greater proportion of upland species than found in the reference wetlands. There were significant differences in soils and vegetation characteristics between younger and older created wetlands, though we could not say older created sites were trending towards the reference wetland condition. Updated site selection practices, more careful consideration of monitoring period lengths, and, especially, a stronger effort to recreate wetland types native to the region should result in increased similarity between created and natural wetlands.  相似文献   

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