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1.
文山州小地老虎发生及迁飞规律研究   总被引:5,自引:0,他引:5  
丁蕙淑 《昆虫知识》1992,29(1):10-13
<正> 小地老虎Agrotis ypsilon Rott.是世界性重要农业害虫,也是文山州山区、坝区大小春旱地作物主要害虫之一,受害轻者缺苗断垄,重者翻犁重栽。为了掌握该虫在我州的发生及迁飞规律,作者于1979~1987年进行了本项研究,其结果如下。  相似文献   

2.
李艳红  关进科  黎大勇  胡杰 《生态学报》2013,33(19):6035-6040
动物的巢为其育幼、避敌和休息等提供了适宜的空间,因此,了解其巢址特征对于物种的保护和管理有着重要的意义。灰头小鼯鼠是一种小型树栖、夜行性哺乳动物,在国内主要分布在中部、南部及西南地区。2012年4月至6月和2012年9月至12月在白马雪山国家级自然保护区对灰头小鼯鼠的巢址特征进行了初步研究。结果表明:灰头小鼯鼠共利用2种巢,在针叶树上,灰头小鼯鼠多利用树枝巢;在阔叶树上,灰头小鼯鼠仅利用树洞巢。巢多紧靠树干(0.2±0.1) m,平均巢高(11.3±0.8) m,巢口无方向偏好。灰头小鼯鼠喜欢选择冠幅更大、通道数更多的树上筑巢,此外,其对郁闭度大,灌木盖度高的生境有明显的选择性。  相似文献   

3.
小地老虎是一种远距离迁飞害虫。通过对成虫种群消长资料的分析表明,在我国境内的越冬基地,成虫种群具有两次(冬、春季)出现高峰;春季蛾量较高,其消长为典型的先坡后陡型。在一代为害区,成虫种群常有三次出现峰(春、夏、秋季);春季成虫均为迁入蛾,其消长为先陡后坡型;夏季蛾蜂高而蛾期短,消长动态属先坡后陡型。影响成虫种群消长的主要原因为虫源及性质、蛾子迁飞特性、气温与天气等。  相似文献   

4.
<正> 关于虫草蝙蝠蛾Hepialus armoricanus Oberthür幼虫的食性,前人报道主要取食珠芽蓼Polygonum viviparum、头花蓼P. sphaerosta、大小黄Rheum pumilum等植物。我们于1984至1987年对云南冬虫夏草的主要寄主白马蝠蛾H. baimaensis Liang幼虫的食性及某些影响取食的因子作了初步观察,现整理出来供参考。  相似文献   

5.
小地老虎雄蛾触角感受器的扫描电镜观察   总被引:1,自引:0,他引:1  
利用扫描电镜观察了小地老虎雄蛾触角感受器的种类、形态和分布.结果表明, 小地老虎雄蛾触角为双栉状(端半部为丝状),由1节柄节、1节梗节和82~92节鞭节组成.在触角上分布有毛形感器、刺形感器、鳞形感器、腔锥感器、腔形感器、 耳形感器、B(o)hm's氏鬃毛7种感受器,其中毛形感器数量最多.  相似文献   

6.
白马雪山国家级自然保护区植物多样性   总被引:1,自引:0,他引:1       下载免费PDF全文
李宏伟  赵元藩   《广西植物》2007,27(1):71-76,99
通过多次对白马雪山国家级自然保护区进行野外实地考察、标本鉴定并查阅有关文献,运用吴征镒植物地理学的原理与方法全面系统地研究保护区植物区系,用计算机数据库程序建立1个有1674种植物地理成分数据库,植物区系统计分析均在数据库中进行。经统计保护区有种子植物135科,565属,1674种。经分析,保护区植物区系是温带山地性质,并兼有丰富的亚热带成分;区系成分新老兼备,分化复杂,以年轻成分为主;替代现象明显、特有现象显著;与北温带联系紧密,高山花卉和现代松柏类植物多样化中心;是中国低纬度高海拔地区植物资源保存比较完整而原始的地区。  相似文献   

7.
为了解云南白马雪山响古箐地区鸟类多样性的垂直分布格局,于2013年7月—2014年2月采用样线法对白马雪山国家级自然保护区响古箐地区的鸟类进行了调查。共记录鸟类139种,隶属9目36科,其中国家Ⅰ级重点保护鸟类2种,国家Ⅱ级重点保护鸟类9种。不同生境中栖居的鸟类种数不同,其中云南松林69种、常绿阔叶林78种、针阔混交林123种、寒温性针叶林45种、高山灌丛草甸24种。从鸟类多样性的结果分析可知,中低海拔的云南松林、常绿阔叶林、针阔混交林具有较高的多样性指数,分别为3.762、3.777、3.786;高海拔的高山灌丛草甸鸟类多样性指数最低,为2.871。同时针阔混交林及以下地区,东洋界鸟类比例随海拔的上升而增加,古北界和广布种所占比例随海拔上升而下降;寒温性针叶林以上地区,古北界鸟类比例随海拔的上升而增加,而东洋界与广布种鸟类的比例则下降。综上所述,响古箐地区鸟类多样性随海拔的升高而呈现出单峰分布的特征。  相似文献   

8.
贡嘎雪山小地老虎迁飞考察   总被引:1,自引:0,他引:1  
<正> 小地老虎Agrotis ypsilon(Rottemberg)迁飞问题早为前人提出。通过海面和空中捕蛾以及成虫标记释放,也证明了迁飞现象的客观存在。但由于虫源地、迁飞路线、飞翔过程等一系列问题尚不很明了,根据小地老虎迁飞来追索虫源地乃是一个重要的途径。从四川各地常年诱蛾情况看,春季从西(偏南)向东(偏北)蛾量是逐渐上开的趋势,秋季则相反,蛾量是逐渐下降的趋势。根据这个启示,为了探讨小地老虎在四川的来龙去脉,了解迁飞的方向和高度,利用地理优势直接观察高空虫群的动态,于1980—1981年,在四川西部凉山州贡嘎雪山山系主峰——夏诺多季峰进行了实地考察。 夏诺多季峰位于四川省木里藏族自治县西  相似文献   

9.
沈发荣  杨大荣 《动物学研究》1989,10(3):232-232,240
本文首次报道了云南冬虫夏草优势寄主昆虫白马蝠蛾5龄幼虫消化系统的构造。用形态解剖学的方法对该虫的前肠、中肠、后肠及唾腺进行了观察研究和描述。结果如下: 白马蝠蛾幼虫的消化道简单的呈长筒状,直占于腹腔中,其前肠、中肠、后肠三部分分段明显(图1)  相似文献   

10.
11.
六索线虫的生态学研究   总被引:1,自引:0,他引:1  
六索线虫的生态学研究李福春,许砚田,聂桂云,方七零(湖南省岳阳农校414000)EcologicalStudyonHexamermissp.¥LiFuchun;XuYantian;NieGuiyun;FangQiling(YueyangAgricul...  相似文献   

12.
    
The common cutworm, Spodoptera litura, is a serious insect pest of many vegetables and crops worldwide. Entomopathogenic nematodes (EPN) have been utilized as biological control agents for controlling various insect pests, including the larvae of S. litura. Many indigenous EPN have been recognized to be more effective in specific field applications. Among the 160 soil samples collected in undisturbed areas of western Thailand, three samples tested positive for EPN. Three indigenous EPN were identified as Steinernema siamkayai namely, EPNKU63, EPNKU70 and EPNKU85, based on ITS and D2/D3 expansion region analysis of the 28s rRNA genes. Additionally, genetic analysis of the symbiotic bacteria using recA rRNA sequences confirmed their identity as Xenorhabdus stockiae namely, PEPNKU63, PEPNKU70 and PEPNKU85. To evaluate their initial biocontrol potential against the 6th instar larvae of Galleria mellonella, virulence assays were conducted. The application of 100 infective juveniles (IJs)/insects resulted in the mortality of 80–100% of G. mellonella larvae after 72 h. When symbiotic bacteria were applied at 1 × 106 cells/insect, they exhibited 63–93% mortality against G. mellonella larvae after 120 h. In further laboratory tests, three S. siamkayai isolates achieved 100% mortality of 3rd instar Spodoptera litura larvae within 72 h, with LC50 values ranging from 29 to 30 IJs/insect. In screenhouse experiments, it was revealed that all S. siamkayai isolates displayed substantial virulence, ranging from 62% to 74%, against 3rd instar S. litura larvae within 72 h. This study demonstrates the biocontrol potential of S. siamkayai in controlling S. litura larvae.  相似文献   

13.
黑鹳(Ciconia nigra)属国家Ⅰ级保护野生动物.2010至2018年,通过样线、样带和固定样点调查的方法对张掖黑河湿地国家级自然保护区的黑鹳种群进行了监测,黑鹳最大种群数量均出现在每年的9月下旬,数量120~430只不等,年均308只.春季迁徙季节,黑鹳于3至4月到达保护区,部分个体会在此繁殖,其他个体会继续...  相似文献   

14.
目的:非小细胞肺癌发生、发展的分子机制仍是目前研究的热点与难点,新近研究表明microRNA在肿瘤的发展过程中起着重要的作用.本研究旨在探讨miR-196a在人非小细胞肺癌组织及细胞系中的表达水平,以及抑制miR-196a对非小细胞肺癌细胞侵袭转移能力的影响.方法:通过real-time PCR技术检测人非小细胞肺癌及细胞系中miR-196a的表达水平,通过转染miR-196a inhibitors抑制miR-196a的表达水平,并通过定量PCR检测转染效率.利用transwell实验检测下调miR-196a对NCI-H1299细胞的迁移、侵袭能力的影响.结果:相对于正常肺组织及细胞,在非小细胞肺癌组织和细胞中miR-196a的表达水平出现了显著的上调,NCI-H1299细胞中转染miR-196a inhibitors能显著抑制miR-196a的表达水平且抑制miR-196a的表达能降低NCI-H1299细胞的迁移、侵袭能力.结论:定量PCR结果显示miR-196a在非小细胞肺癌组织及细胞中表达显著上调,而封闭其表达能影响非小细胞肺癌细胞的迁移和侵袭功能,提示miR-196a的表达上调可能在非小细胞肺癌的发生、发展中起着关键的作用,并有可能作为将来非小细胞肺癌诊断、预后的分子靶标.  相似文献   

15.
Background : The Snowy Mountains contain Australia's longest-lasting snowpatches. Because of climate change, their longevity has declined, with the loss of some specialist vegetation in the underlying snowbeds.

Aims: To characterise the current status of the vegetation associated with the longest-lasting snowpatches in Australia and its association with abiotic factors.

Methods: We assessed plant composition, soil depth, moisture and nutrients and subsurface temperatures in five zones of increasing vegetation height and cover in snowbeds.

Results: The zone beneath the middle of snowpatches was characterised by little vegetation cover and lower species richness, later emergence from snow, skeletal soils, and lower mean soil temperatures than zones further downslope where soils increased in depth and nutrient levels. Vegetation beneath these snowpatches no longer occurs in distinct communities. Plants have not simply migrated upslope, instead, areas that have deep soil that used to have snowpatch specialist species are being colonised upslope by grasses and downslope by tall alpine herbfield species that prefer bare ground.

Conclusions: Reduced longevity of Australia's longest-lasting snowpatches has led to the loss of distinct snowpatch plant communities. With limited soils beneath the centre of current snowpatches, and a lack of other suitable sites there is no location for these plant communities to migrate to.  相似文献   

16.
    
The mountain pine beetle is killing many trees in Colorado's high‐elevation forests. The thinned canopies found in dead tree stands should intercept less snow and transmit more radiation than canopies in living forests, altering snow accumulation and melt processes. We compare snow, forest, and meteorological properties beneath living and pine beetle‐killed tree stands. Eight pairs of living and dead tree stands were monitored over two years along the headwaters of the Colorado River. During year one, all eight dead stands were in the red phase of tree death — the trees still retained needles. Snow accumulation was the same under living and red phase stands, but snow melt was more rapid in red phase stands. As a result, the snowpack was depleted one week earlier in the red phase stands. Canopy shortwave transmission was not higher in red phase stands. We hypothesize that the faster melt and earlier depletion in red phase stands was caused by accelerated needle loss which lowers the albedo of the snow surface. By year two, many of the dead trees had progressed to the needle‐less grey phase of tree death. Snow accumulation in grey phase stands was 15% higher than in paired living stands. Snow in grey phase stands melted more rapidly than in living stands, likely as a result of increased canopy shortwave transmission. We combine our results with those from previous studies to develop a conceptual model that describes how beetle infestation affects snow accumulation and melt in the different stages of mortality. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

17.
1.  Persistent organic pollutants (POPs) can be trapped by and accumulate in cold regions. To understand POP accumulation in temperate high mountain lakes, we collected samples of snow from the catchments of several high mountain lakes in Europe.
2.  Organochlorine compounds (OCs) are regularly found in snow collected in European high mountain sites. Polychlorobiphenyls (PCBs) were found in all samples examined. Hexachlorocyclohexanes (HCHs) are also common whereas DDTs and hexachlorobenzene were found less frequently.
3.  Comparison of the concentrations of these pollutants in snow with OC levels in the waters of these lakes or atmospheric deposition during cold periods shows that the snowpack constitutes a significant seasonal PCB reservoir in all catchments and that snow trapping is a major mechanism for the incorporation of HCHs in the lakes situated in the coldest sites, e.g. Gossenköllesee in the Alps.
4.  Correlation of the concentrations of the PCB congeners in snow versus mean annual winter temperature shows higher accumulation at lower temperatures. The less volatile PCBs exhibit higher temperature dependences than the more volatile congeners. This trend differs from altitudinal dependences observed in other sites such as Canada and may be related to the specific range of winter temperature in each area of study.  相似文献   

18.
    
Three oligosporogenic mutants of Bacillus thuringiensis were assayed for toxicity against larvae of the Indian meal moth, Plodia interpunctella, and the almond moth, Ephestia cautella. The results were compared with insecticidal activity obtained from the parent strain (HD-1) and two standard B. thuringiensis formulations (HD-1-S-1971 and HD-1-S-1980) against the same insect species. The toxicity of the sporeless mutant preparations was significantly diminished against the Indian meal moth (10- to 26-fold increase in LC50) but exceeded the toxicity of the standards against the almond moth. The toxicities of the B. thuringiensis preparations toward the Indian meal moth were consistent with the number of spores in the test samples, but spores did not contribute to toxicity to E. cautella larvae. A rationale for basing dosage on soluble protein was demonstrated for use in situations where spores are not a contributing factor in toxicity.  相似文献   

19.
掌握种群动态以及迁徙习性对濒危候鸟的保护至关重要。2004~2005、2007~2008、2008~2009年的冬季(10月~次年4月),采用夜栖地直接计数法对云南省纳帕海湿地黑鹳(Ciconia nigra)的种群数量进行了监测。结果表明,在2004~2005、2007~2008、2008~2009年冬季,纳帕海湿地越冬黑鹳种群平均数量分别为39.6、128.6、181.8只,呈逐年增加的趋势;通常黑鹳10月下旬迁来,至次年3月中下旬迁离;纳帕海同时也是繁殖于蒙古国的黑鹳迁往印度越冬地的重要停歇地,过境时间集中在 11月中上旬。纳帕海湿地已经成为国内最为重要的黑鹳越冬地和迁徙停歇地,建议当地管理部门加强湿地管理,维持适当的浅水区域作为黑鹳的觅食地,另外需加强旅游管理,减少游客对黑鹳的干扰。  相似文献   

20.
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