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1.
新疆阿拉尔地区近53年气候变化特征分析   总被引：3，自引：0，他引：3  
根据新疆阿拉尔地区1961-2013年逐日平均气温、最高气温、最低气温、日照时数、平均风速、降水量等气象资料,采用Penman-Monteith模型、气候倾向率和Mann-Kendall非参数检验法分析了阿拉尔地区近53年气候变化特征。结果表明:1)阿拉尔地区年平均气温、最低气温呈"低-高-低"的动态变化;最高气温呈"高-低-高"的动态变化,1987年为气温年突变点。2)阿拉尔地区自1987年以来,春季最低气温增幅为0.19℃/10a(p﹤0.05),夏季最低气温减幅为0.044℃/10a(p﹤0.05),秋季平均气温和最低气温减幅分别为0.117℃/10a(p﹤0.01)和0.004℃/10a(p﹤0.01),冬季平均气温、最高气温和最低气温减幅分别为0.681℃/10a(p﹤0.01)、0.478℃/10a(p﹤0.05)和0.606℃/10a(p﹤0.01),呈"春暖-夏暖-秋冷-冬冷"的动态变化。3)阿拉尔地区20世纪90年代前,降水负距平占66.7%,k值>32的年份占64.2%,气候极端干燥;20世纪90年代后,降水正距平占61.3%,k值>32的年份占52%,气候相对湿润,呈"干-湿"的动态变化,干燥度均在16以上。  相似文献   

2.
1980-2009年西藏西北部潜在蒸散时空分布特征及其影响因素   总被引：3，自引：0，他引：3  
通过分析西藏西北部潜在蒸散量的时空分布以及影响潜在蒸散的气候因素.结果表明:①西藏西北部潜在蒸散呈现从西北向东南减少的分布特征,最大潜在蒸散出现在夏季,春季次之,冬季最小.近30 a来,除冬季潜在蒸散呈略微增加趋势外,其余均呈减少趋势.气温、相对湿度和降水量呈增加趋势,平均风速和日照时数呈减少趋势;潜在蒸散与气温、风速、日照时数呈正相关,与相对湿度、降水量呈负相关.②影响潜在蒸散的主要气象要素为相对湿度、平均气温和日照时数,风速对冬季潜在蒸散的影响最为显著;近30 a来,风速减小、日照时数减少、相对湿度增加是导致潜在蒸散量减少的主要气象影响因子.西藏西北部地区潜在蒸散的变化存在“蒸发悖论”现象,即在气温升高[0.55℃·(10a)-1]的背景下,潜在蒸散呈下降趋势[10.02 mm ·(10a)-1].  相似文献   

3.
多伦县近60年气候变化分析   总被引：2，自引：0，他引：2  
利用多伦县气温、降水量、平均相对湿度、平均风速和日照时数资料,采用线性倾向估计、5年滑动平均等方法,分析了该地区近60年(1953-2012)的气候变化趋势。结果表明:年平均气温和季平均气温均呈上升趋势,年平均气温倾向率为0.39℃/10a,冬季增温对年增温贡献率最大,倾向率达0.57℃/10a;年降水量呈下降趋势,倾向率为-7.17mm/10a,夏季降水量对年降水量下降的贡献最大;平均相对湿度、平均风速和日照时数也均呈下降趋势,年倾向率分别为:-0.82%/10a、-0.11(m/s)/10a、-51.95h/10a,对年下降贡献最大的季节分别为冬季、冬季和春季;与全国、锡林郭勒盟及浑善达克沙地的气候变化趋势基本一致。  相似文献   

4.
基于水热耦合平衡的长江源实际蒸散变化研究   总被引：1，自引：0，他引：1  
采用1960~2012年长江源地区8个气象站的气象数据和直门达站的径流数据,基于流域水热耦合平衡方程计算了长江源区实际蒸散(ET),采用云模型、Mann-Kendall检验、Pettitt检验和Sen趋势度等方法分析了ET的时空变化特征,并通过敏感性分析确定了影响ET的主要气候因子。结果表明:1)1960~2012年长江源区多年平均ET为277.6mm/a,呈显著上升趋势(99%置信度),上升速率为6.27mm/10a,并在1997年发生突变(99%置信度)。2)年均ET从西北向东南递增,且上升速率从西北向东南递减。熵值En和超熵He分别呈西高东低和西北高东南低的分布规律。ET均值大的区域年ET随时间变化较为均匀且稳定性较强。3)源区年ET变化对降水最为敏感,其后依次是相对湿度、日照时数、最高气温、风速、最低气温和平均气温。降水量上升对ET的增加起主要贡献作用,其次是气温与日照时数的上升和相对湿度的下降。  相似文献   

5.
甘肃省参考作物蒸散量及影响因素的时空分异特征   总被引：1，自引：0，他引：1  
为了探寻甘肃省参考作物蒸散量(ET0)的变化特征及其影响因子,利用甘肃省29个气象测站1951—2013年的观测资料,采用FAO-Penman-Monteith(98)公式计算甘肃省不同区域的ET0,并依靠线性趋势方程、云模型、通径分析和指标敏感性分析方法对ET0时空分异特征和影响因子进行分析。结果表明:甘肃省ET0以2.11mm·10a-1的倾向率呈现出增长趋势,除河西地区以0.71 mm·10a-1的倾向率呈递减趋势外,其余三个地区均呈增长状态。ET0空间分布总体上呈现为西北地区大于东南地区,河西地区最为离散、不稳定,陇东地区最为均匀、稳定。ET0的主要影响因子具有空间变异性,河西和陇南地区为平均温度,陇中和陇东地区为平均相对湿度和日照时数。但是ET0的变化是多因素共同影响的结果,平均风速是河西地区和陇东地区的另一主要影响因素,陇中地区为平均相对湿度,陇南为日照时数。  相似文献   

6.
黄河流域水分盈亏量时空变化及其影响因素   总被引：2，自引：0，他引：2  
基于1960-2013年黄河流域66个气象站点的实测数据,利用Morlet函数、Mann-Kendall检验、偏相关分析,探讨水分盈亏量的时空变化及影响因子.结果表明:流域多年平均水分盈亏量在-1 252.4～134.2 mm,全流域均值为-603.4 mm,并呈现出“南高北低、东高西低”的空间分布特征.秋季水分亏缺量最大,夏季、冬季次之,春季最小.全流域水分盈亏量年、春、夏、秋、冬季的线性倾向率为-6.39 mm·(10a)-1、-4.48 mm·(10a)-1、-4.96 mm·(10a)-1、2.68 mm·(l0a)-1、-0.59 mm·(10a)-1;年水分盈亏量有42个站点下降,22个上升,2个无变化.变化第一主周期依次为26 a、12 a,流域平均水分盈亏量在1993年发生了一次减少突变,存在突变年份的站点共45个.降水量是年水分盈亏的主导因子,偏相关系数达0.94,其次为湿度、水汽压,日照时数、平均气温和风速.  相似文献   

7.
近50年黄土地区气候与潜在蒸散量变化及其影响因素分析   总被引：1，自引：0，他引：1  
根据黄土地区1951—2000年14个站点的日气象资料以及FAO56 Penman-Monteith公式,计算各站逐月潜在蒸散量,分析近50 a各站年平均气温、降水量、日照时数、风速和相对湿度等气候要素以及年潜在蒸散量的变化趋势和变化特征,并据此分析ET0变化的气候成因。结果表明:(1)近50 a来黄土地区基本都表现为显著的增温趋势,增温速率为0.039～0.396℃/10a,与全国平均水平0.22℃/10a相当;降雨量、风速、日照时数和相对湿度总体上均呈下降趋势;(2)潜在蒸散量年际间除驻马店和介休显著下降外,其他大部分站点呈显著上升趋势;(3)敏感性分析表明黄土地区潜在蒸散量的主要影响因素是相对湿度,其次是太阳辐射(日照时数)和气温,风速变化的影响最弱。  相似文献   

8.
基于新疆56个气象站1961—2019年逐日地面观测数据,分析了过去59 a间新疆干湿变化特征及其成因,主要结论如下：(1)新疆正经历显著的由干向湿的转变。在1961—2019年期间,区域平均干燥度指数(Aridity Index,AI)以0.01·(10a)-1的速率上升(P<0.01),并于1987年前后发生突变。全区呈显著上升趋势的站点占比为57.1%。(2)1961—2019年间新疆年降水量以8.6 mm·(10a)-1的速率显著增加,突变时间与AI突变时间一致。年参考作物蒸散量(reference evapotranspiration,ET0)在1961—2019年可检测到显著的下降趋势,变化速率为-15.7 mm·(10a)-1。但值得注意的是,年ET0在1990年前后发生转变,1990年以前持续下降,1990年后转为波动上升。(3)ET0的变化主要受风速与相对湿度两种气候因子的控制。在1961—2019年间,全区风速基本呈下降趋势,有接...  相似文献   

9.
南疆阿拉尔地区近31年沙尘天气变化特征及影响因素   总被引：1，自引：0，他引：1  
根据南疆阿拉尔地区1981-2011年逐日沙尘日数、平均气温、平均相对湿度、平均风速、降水量、蒸发皿蒸发量和大风日数等气象资料,采用气候倾向率、距平和距平相关方法分析了阿拉尔地区近31年沙尘天气变化特征及影响因素。结果表明:1)近31年阿拉尔地区浮尘日数﹥扬沙日数﹥沙尘暴日数,整体呈减少趋势,减幅分别为2.4d/10a、8.2d/10a和45.1d/10a,累计减少了7.4d、25.4d和56.7d。2)阿拉尔地区沙尘天气呈"春﹥夏﹥秋﹥冬"的季节分布,4月、5月为沙尘天气高发时段,12月、1月是低发时段;四季(春、夏、秋、冬)沙尘天气呈减少趋势,累计减少了1.2d、5.6d、23.6d,4.3d、12.7d、19.5d,1.2d、5.9d、9.0d和0.6d、1.2d、5.3d。3)近31年阿拉尔地区年沙尘天气减少主要与蒸发量减少、平均风速降低、大风日数减少和平均相对湿度增大有关,与平均气温、降水量和干燥度无关;季沙尘天气减少是由蒸发量减少、干燥度减小、平均风速降低、大风日数减少和平均相对湿度增大等多种气象因子共同作用,与平均气温和降水量关系不大。  相似文献   

10.
柴达木盆地平均风速与大风日数的变化特征   总被引：5，自引：0，他引：5  
利用1971-2O10年柴达木盆地8个气象站观测资料,采用气候统计诊断分析方法,对柴达木盆地平均风速和大风日数的变化趋势及突变特点进行研究。结果表明:近40a柴达木盆地平均风速、大风日数的年、季、年代际变化均呈下降趋势。年平均风速下降幅度为-0.28m·s-1/10a(P0.01),四季平均风速减小幅度表现为夏季春季秋季冬季的气候特征;年平均大风日数减少幅度为-5.8d/10a(P0.05),以夏季减幅最明显,秋、冬季减幅最小;大风天气最多的季节是春季,占年大风日数的44.2%,春季大风日数最多且风速较大,秋季大风日数最少且风速较小,主要与大气环流系统的活动有关;年、季平均风速的异常年份出现在20世纪70年代,这与20世纪70年代荒漠化程度比较严重有一定的关系;气温、降水量与大风日数呈明显的负相关,这在很大程度上解释了大风呈减少趋势的原因,而降水的显著增加是主要原因之一。  相似文献   

11.
Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.  相似文献   

12.
Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.  相似文献   

13.
We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.  相似文献   

14.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

15.
Plant Viruses Transmitted by Whiteflies   总被引：18，自引：0，他引：18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

16.
《干旱区科学》2014,(6):782-782
正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad  相似文献   

17.
Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.  相似文献   

18.
A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

19.
The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.  相似文献   

20.
Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.  相似文献   

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