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1997年至 2 0 0 0年 ,作者等在新疆准噶尔盆地东部木垒县境内开展了波斑鸨 (Chlamydotisundulata)的生态学研究工作。研究内容涉及栖息地 ,种群数量和密度 ,巢与卵 ,筑巢成功率和孵化率 ,食性 ,迁徙。研究结果表明 ,波斑鸨多在植被盖度 ,高度和草本植物丰富度较低的地带繁殖栖息 ;研究区内约有成年波斑鸨 2 5 1- 2 93只 ,平均密度为 0 .0 838只 /km2 ;从 1998年至 2 0 0 0年 ,平均巢卵数分别为 :3.9± 0 .8,3.7± 0 .9和 3.0± 0 .9。孵化成功率为 0 .83~ 1。营巢成功率为 0 .2 5~ 0 .775 ;波斑鸨以多种植物和无脊椎动物为食 ,其中猪毛菜 (Salsolaarbuscula)是一类重要的食物 ;波斑鸨多在 9月中至 10月中开始秋季迁飞 ,平均迁徙天数为 2 4± 17天 ,飞越 34 0 0 - 470 0km ,在伊朗、印度和巴基斯坦越冬 相似文献
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内蒙古乌拉盖地区景观破碎化与土地利用对策的研究 总被引:11,自引:3,他引:8
本文利用RS,地面调查和GIS相结合的手段,对位于内蒙古锡林郭勒盟东北部的乌拉盖草甸草原区景观破碎度分3个时期(1988-1992,1993-1995,1996-1997年)进行动态研究,并选用3种不同的指标:斑块密度指数、廊道密度指数、景观班块破碎化指数,对该区的景观破碎度进行了测算分析,进而探讨了该区土地利用存在的问题和对策。结果表明:1.总体班块密度指数在三个时期分别为0.0125个.km-2、0.0582个.km-2、0.112.km-2;2.廊道密度指数在三个时期都约为0.0538km.km-2;3.整体景观斑块数破碎化指数在三个时期分别为0.0025、0.0116、0.0223。说明,随着人类干扰的增加,景观的破碎化程度加大,土地利用不合理的有关问题不容忽视。 相似文献
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采用二次回归最优设计,研究苏云金素对东亚小花蝽捕食作用的影响,得出日均捕食量(y)与猎物(x1)和捕食者(x2)之间互作关系模型。处理捕食数量回归方程:y=-0.0021x21+1.2112x22+0.8822x1-10.3465x2-0.0649x1x2+1.7174;对照捕食数量回归方程:y=-0.0017x21+0.7734x22+0.6941x1-6.4914x2-0.0474x1x2-0.4636。综合定性分析和定量分析结果,苏云金素处理东亚小花蝽若虫,减弱了其对二斑叶螨卵的捕食能力,但二者的差异不显著,对种群变化影响不明显 相似文献
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天然湖泊蒸发量之测算 总被引:3,自引:0,他引:3
用基本站上的φ20cm水面蒸发器,埋于湖边滩地的E501k型水面蒸发器和湖泊附近的20m^2与E601之比值(K2)测算湖泊蒸发量,取得成功,由于湖面蒸发的不均匀性,基本站在上风的湖边时折算系数(K1.K2)为0.45;在上风向离湖边1.5km时为0.40;在湖的下风向,离湖边15km时,折算系数为0.61-0.62;在上风的湖边为0.38-0.39。用经验公式计算也应做站址位置修正(K4)和风向 相似文献
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采用二次回归最优设计,研究苏云金素对东亚小花蝽捕食作用的影响,得出日均捕食量(y)与猎物(x1)和捕食者(x2)之产作关系模型。处理捕食数量回归方程:y=-0\0021x1^2+1.211x2^2+0.8822x1-10,3465x2-0.0649x1x2+1.7174;对照捕食数量回归方程:y=-0.0017x1^2+0.7734x2^2+0.6941x1-6.4914x2-0.0474x1x2 相似文献
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苏云金杆菌SD—5菌剂防治大豆银纹夜蛾的研究 总被引:2,自引:0,他引:2
试验结果表明BtSD-5对银纹夜蛾幼虫具有高毒力、纯化晶体的毒力比孢昌混合物高,毒杀速度也较快;SD-5对银纹蛾化蛹和羽化均有明显影响;田间小区药效试验表明SD-5 0.2×10^8、0.5×10^8、1×10^8活芽孢/mL6天的防效分别为90.1%、96.9%和97.8%;示范推广123.6hm^2,平均防效为91.85%;SD-5处理区天敌种类和数量明显高于化防区;SD-5田间喷施后第8天毒 相似文献
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零频率估计二化螟危害株密度方法的研究 总被引:2,自引:0,他引:2
零频率估计二化螟危害株密度的3种方法为:(1)X=0.8743(P0-1.1438-1);(2)X=exp{[ln(-lnP0)+0.6997]÷0.9514};(3)X=2.0131(-lnP0)1.0153。其中以第3种方法估计精度最高,误差小,应用效果最好。依据Gerrard方法建立了理论抽样数模型:n=b2(1-P0)/P0(lnP0)2(cv)2。田间验证表明,样本数50~100丛,即可把抽样误差控制在20%以内,完全符合田间调查精度要求,可提高工效3~5倍 相似文献
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1999~ 2 0 0 1年 6~ 7月 ,利用粪便示踪和野外直接观察法对准噶尔盆地东部波斑鸨 (Chlamydotisundula tamacqueenii)夏季栖息地进行了采样研究。结果表明 :波斑鸨夏季栖息地地势平坦 ,视野开阔 ,沙质土和粘土上旱生和盐生荒漠植被广泛分布 ,植被稀疏、低矮 ,并镶嵌有相对较高的灌丛块 ;影响波斑鸨夏季栖息地选择的环境因子是植物种数、植被密度和植被盖度 ;栖息地内的植被盖度、植被密度、草本植物种数、角果藜密度和距邻近灌丛块距离都显著低于对照地内的相应成分。 相似文献
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中国鸨类的分布与现状 总被引:5,自引:0,他引:5
依据1990-2002年调查资料,分析了我国国家一级保护动物3种鸨类的分布和现状.大鸨(Otis tarda):东方亚种(O.t.dybowskii)中国种群繁殖于黑龙江西南部、吉林西部、内蒙古东部和中部、宁夏北部和甘肃,少数个体滞留在南部繁殖地越冬.指名亚种(O.t.tarda):中国种群繁殖于新疆北部和西部.越冬区尚不清楚,推测可能在南亚一带,新近在新疆察布查尔发现越冬个体.繁殖地生境为草原、荒漠草原和农田;越冬地生境为挥湖沿岸滩涂、草甸、草甸草原和麦地等.波斑鸨(Chlamydotis undulata macqueeni):中国种群繁殖于准噶尔盆地周边、乌伦古河两岸、巴里坤及吐鲁番盆地南部、内蒙古西部和甘肃西部.准噶尔盆地东部木垒东北为国际间的主要繁殖区之一.生境为荒漠和荒漠草原,越冬地在西亚和南亚一带.小鸨(Tetrax tetrax ):中国种群繁殖于新疆北部,我国为繁殖区的东界.生境为草原和半荒漠,越冬于南亚一带.我国种群数量十分稀少. 相似文献
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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
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Sergio Ovruski Martín Aluja John Sivinski Robert Wharton 《Integrated Pest Management Reviews》2000,5(2):81-107
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
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Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops 总被引:9,自引:0,他引:9
Antonio Logrieco Antonio Bottalico Giuseppina Mulé Antonio Moretti Giancarlo Perrone 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(7):645-667
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
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Paul W. J. Taylor Rebecca Ford 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(1):127-133
Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection
in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However,
where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas.
Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based
on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences
in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes
is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult
for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs
to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for
each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within
populations is important in the selection of resistant genotypes. 相似文献
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《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