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1.
1987年、1988年在四川卧龙自然保护区五一棚观察站对复齿鼯鼠(Trogopterue xanthipes)的筑窝情况进行观察。观察站(海拔2520米),大部分为原始森林,少部分为次生林。有云杉、冷杉、桦木、拐棍竹、忍冬、荚蒾等,林内阴湿,地衣、苔藓较多。复齿鼯鼠一般傍晚出巢觅食,偶尔也见白天出巢活动。曾见一只复齿鼯鼠在巢区附近的冷杉树上,以桦木嫩叶为食。又曾见一只复齿鼯鼠从巢内滑翔于荚蒾树上,以其叶为食。复齿鼯鼠筑窝地点多样,作者共发现四个窝:一窝筑于冷杉树上,离地5—6米。一窝筑于桦木树上,离地15—17米,另两窝筑于宝兴栒子树上,离地3—5米…  相似文献   

2.
【目的】柑橘大实蝇是一种严重为害柑橘类果实的经济害虫。研究其精巢、精泵以及精泵内骨骼生长发育状况,有助于提高柑橘大实蝇人工繁殖效率以及其田间防治效果,为柑橘大实蝇的预测预报及防治提供理论基础。【方法】基于光学显微镜测量恒温和室温条件下柑橘大实蝇雄虫的精巢、精泵以及精泵内骨骼的长度和宽度,并建立其长度、宽度和指数的函数模型,比较恒温和室温2种饲养条件下其雄虫器官发育状况差异。【结果】无论是在恒温还是室温条件下饲养,随着柑橘大实蝇雄成虫日龄的增加,其精巢、精泵以及精泵内骨骼的长度、宽度和指数变化趋势均符合幂函数增长模型。在恒温和室温条件下,其雄虫的精巢宽度、精泵的长度和宽度以及指数、精泵内骨骼宽度均无明显差异。在室温条件下饲养的雄虫的精巢长度[(4.00±0.14) mm]及指数(3.40±0.14)、精泵内骨骼长度[(1.65±0.03) mm]及指数(1.84±0.08)均分别显著高于在恒温条件下饲养的雄虫的精巢长度[(3.75±0.13) mm]及指数(3.19±0.14)、精泵内骨骼长度[(1.61±0.03) mm]及指数(1.77±0.08)。【结论】变温(室温)比恒温更有利于柑橘大实蝇雄虫的精巢和精泵内骨骼的发育,并推荐使用精泵长度推断其雄虫日龄的方法。  相似文献   

3.
圈养大熊猫野化培训期的生境选择特征   总被引:1,自引:0,他引:1  
大熊猫(Ailuropoda melanoleuca)是我国特有的珍稀物种,也是世界上最濒危的野生动物之一。为了将人工繁育的部分大熊猫个体重引入其历史分布区或复壮野生种群,中国保护大熊猫研究中心从2003年开始进行圈养大熊猫的野外放归工作,通过野化培训以提高圈养大熊猫适应和选择野外环境的能力。对野化培训大熊猫"淘淘"的生境选择研究表明:该野化培训大熊猫幼仔经常活动于新笋密度较大的区域[生境与对照:(2.68±1.14)对(1.58±0.66)],却避开成竹密度过大[(9.91±2.51)对(12.18±4.68)]、竹子较高[(4.57±1.09) m对(4.98±0.66) m]以及枯死竹过多[(2.52±0.86)对(3.39±1.33)]的区域;喜欢活动于离水源[(1.59±0.67)对(2.19±0.87)]和隐蔽场所较近[(5.37±2.14) m对(8.35±7.76)m],以及距离乔木较远[(3.09±0.69) m对(2.70±0.42) m]和郁闭度较低[(1.85±0.57)对(2.10±0.47)]的区域(P < 0.05),新笋密度大小是该栖息地在整个野化培训期间是否被利用的最重要因素。该野化培训大熊猫幼仔保持着与带仔母兽相近的生境选择特征,对竹子环境的选择也与卧龙野生大熊猫相似,野化培训对该大熊猫幼仔产生了积极的作用。野化培训大熊猫幼仔形成的家域和核域面积分别为9.21 hm2 和1.93 hm2,占野化培训圈面积的51.95%和10.89%,其中家域面积仅有卧龙野生大熊猫的1.4%-2.4%,所以在以后的野化培训过程中需要采取增加野化培训圈中环境丰富度等方式,促进野化培训大熊猫形成较大的家域面积。  相似文献   

4.
航道整治期间为受扰动江豚提供临时庇护所,是在就地保护和迁地保护之外的一种尝试。2020年1月至2021年12月,在长江干线武汉至安庆段6 m水深航道整治过程中,选取马当圆水道建设长江江豚临时庇护所,通过禁止渔业捕捞,增殖放流和通航引导等措施来提升庇护所质量。监测结果表明,庇护所设立后其作为长江江豚栖息地的质量得到提高:夏季鱼类密度从(3361.2±1991.7)条/hm2上升到(12439.1±10734.5)条/hm2,冬季鱼类密度从(501.3±381.8)条/hm2上升至(1684.4±3770.9)条/hm2。通航船舶显著减少,水下噪声低于长江干流的平均水平。长江江豚临时庇护所建立后,枯水期庇护所水域内长江江豚的平均目击次数(4.3±0.6)、观察头次(6)和群体大小(1.4±0.5)都要显著高于庇护所建设前(P<0.05),丰水期则无显著性差异(P>0.05),说明庇护所在枯水期发挥了对长江江豚的保护作用。但长江江豚对庇护所的利用主要集中在进出水道两端,可能是枯水期部分水域过浅限制了江豚对庇护所的利用。分析认为,航道整治等涉水工程施工期间为江豚提供临时庇护所是一项可行措施,但要充分发挥庇护所对江豚的保护作用,必须全面考虑江豚对各项生态因子的需求,防止因关键因子带来的"木桶效应"制约庇护所的整体适合度。  相似文献   

5.
2007年春季,在天津八仙山自然保护区对狍卧息地利用进行了研究。共发现52个狍的卧息地,同时设置93个对照地。资源选择指数结果表明,狍偏好阔叶林,利用中上坡位,喜欢阳坡和半阴半阳坡,选择水源距离适中,偏爱远离人为干扰的卧息地。逐步判别分析结果显示,灌木盖度、隐蔽度、灌木高度、郁闭度、灌木距离和坡度是判别卧息地和对照地的关键因子,即为影响其卧息地利用的主要因子,判别正确率为98.1%。作为生性胆怯易惊的偶蹄类,具有隐蔽条件较好[灌木盖度适中(转换后为16.77&#177;1.07。)、隐蔽度高(29.54&#177;1.47m)、灌木高度稍高(1.22&#177;0.05m)]的地点是狍适宜的卧息地,以逃避捕食者;与此同时,卧息地较舒适[郁闭度低(转换后为5.48&#177;0.31&#176;)、灌木距离较远(2.99&#177;0.13m)、坡度小(2.11&#177;0.09&#176;)],以利于怀孕母狍呼吸与活动,反映其繁殖期生理需求。  相似文献   

6.
四种同域分布洞巢鸟的巢址特征比较   总被引:2,自引:0,他引:2  
洞巢鸟集团是中国东北地区温带次生林内鸟类群落的重要组成部分,对于其巢址特征的比较研究有助于深入了解鸟类群落动态的内在机制。作者于2008年4-7月,对吉林大岗林场4种主要洞巢鸟的巢址特征进行了调查,并从多尺度(巢树、巢址和活动区)比较分析,进而探讨了初级洞巢鸟与次级洞巢鸟的关系。共发现160个繁殖巢,其中初级洞巢鸟58巢,包括大斑啄木鸟(Dendrocopos major)24巢和灰头绿啄木鸟(Picus canus)21巢;次级洞巢鸟102巢,包括白眉姬鹟(Ficedula zanthopygia)38巢和普通?(Sitta europaea)45巢。初级洞巢鸟对巢树无显著选择性,而次级洞巢鸟对巢树有显著选择性,以白皮柳(Salix pierrotii)为主。灰头绿啄木鸟的洞口主要朝南,而其他3种洞巢鸟对洞口朝向没有显著的选择性。初级洞巢鸟巢址特征的差异主要表现在巢树和巢址尺度上,而次级洞巢鸟在3个尺度上均有显著差异。逻辑斯蒂回归分析表明,区分大斑啄木鸟和灰头绿啄木鸟洞巢的关键因子为洞口直径和洞巢内径,即洞巢的大小;区分白眉姬鹟和普通?洞巢的关键因子为巢树树冠高度和洞口深度。也就是说,初级洞巢鸟之间以及次级洞巢鸟之间巢址特征的最主要差异均在巢树尺度上。判别分析表明,普通?倾向于选择灰头绿啄木鸟提供的洞巢,而白眉姬鹟偏好于大斑啄木鸟提供的洞巢。由于啄木鸟所凿洞巢的大小不同,导致了次级洞巢鸟对其巢址的差异性选择。因此,洞巢的大小是影响同域分布的洞巢鸟巢址利用的最重要因素。  相似文献   

7.
雅鲁藏布大峡谷地区海拔高差大,开发程度较低,生物多样性高,生态系统保存相对完整,近年来不断有新的物种和记录发现。2020年10月至2021年11月,我们在西藏墨脱县、波密县和米林县雅鲁藏布大峡谷区域内布设红外相机进行生物多样性本底调查,选择了7个不同海拔样区,累计设置116个红外相机位点(海拔范围646–4,360 m),监测24,741个相机工作日,获得独立有效视频12,010段。近一年的调查共记录到物种136种,其中可确定物种的兽类37种,分属4目14科,此外还记录到难以定种的鼠兔、鼠类和蝙蝠;鸟类99种,分属9目28科;记录到国家I级重点保护野生动物共14种,国家Ⅱ级重点保护野生动物37种。本次拍摄到10个之前红外相机监测未拍摄到的兽类和雉类物种,包括林麝(Moschus berezovskii)、马麝(M. chrysogaster)、棕熊(Ursus arctos)、亚洲狗獾(Meles leucurus)、黄鼬(Mustela sibirica)、灰头小鼯鼠(Petaurista caniceps)、黑白飞鼠(Hylopetes alboniger)、灰鼯鼠(Petauri...  相似文献   

8.
王静  孙军平  徐涛  祁军  张远林  张学炎  孟秀祥 《生态学报》2020,40(21):7997-8004
综合采用样线法、粪堆计数法及重复调查法对甘肃省兴隆山国家级自然保护区的野生马麝(Moschus chrysogaster)进行了种群调查,结合生境分析,确定了其种群分布、数量特征及影响因素。结果表明,兴隆山保护区分布有野生马麝(1159±275)头,平均种群密度为(3.51±0.83)头/km2;各植被类型生境中的野生麝种群数量及密度存在差异,灌丛生境分布有70%的野生马麝种群,达(807±170)头,种群密度为(6.49±1.63)头/km2;针叶林种群密度最大,达(8.85±83.25)头/km2,分布有野生麝(123±45)头;针阔混交林分布最少,仅(41±15)头,种群密度为(5.00±1.84)头/km2;人工林生境无野生马麝分布。保护区各植被类型生境中的野生马麝种群分布差异反映了马麝对适宜生境功能的需求,食物、保温和隐蔽性是制约野生马麝冬季分布和种群数量的关键因素。此外,因生境及人为干扰强度的不同,保护区各区域的野生马麝种群分布存在差异。建议通过减少人为干扰、地表植被管理及人工林管理优化等措施增加生境适宜性,促进兴隆山自然保护区野生马麝种群的快速恢复和增长。  相似文献   

9.
黄枝油杉为中亚热带喀斯特地区珍贵树种,该物种分布范围狭窄,野生种群幼苗数量少,严重限制了其自然更新。为探求该物种濒危的原因,同时为其保护和利用提供参考,该文对黄枝油杉的种实性状进行了测定,并研究了温度、光照、土壤含水量、基质、贮藏温度和时间、不同地理种源等因素对种子萌发的影响。结果表明:(1)黄枝油杉球果平均结种率为7.45%±6.54%,种子有较长种翅[(2.27±0.32)cm],种子平均长度为(1.55±0.15)cm(不含种翅),平均宽度为(0.62±0.05)cm,平均厚度为(0.46±0.04)cm,平均千粒重为(214.81±14.76)g,风干种子平均含水量为15.28%±1.66%。(2)黄枝油杉种子萌发的适宜温度为25 ℃,在20 ℃和30 ℃下萌发率显著降低(P<0.05); 种子萌发不需要光照,但周期性光照条件下的萌发率显著高于持续光照和持续黑暗条件(P<0.05); 种子在土壤含水量为10%~30%条件下均能萌发,且能耐一定程度的干旱; 适宜萌发基质为质地疏松、透气性好的泥炭土和珍珠岩; 种子不耐贮藏,采集后应及时播种; 3个不同地理种源中以桂林恭城县三江乡种群种子萌发率最高。黄枝油杉球果结种率较低,种子萌发对温度要求严格,且种子易失去活力,这可能与其濒危有很大关系。  相似文献   

10.
2012~2016年每年的4~8月,在贵州宽阔水国家级自然保护区记录到7种雀形目鸟类的巢共20个,分别为绿翅短脚鹎(Hypsipetes mcclellandii)2巢、斑胸钩嘴鹛(Pomatorhinus erythrocnemis)2巢、灰背燕尾(Enicurus schistaceus)1巢、灰眉岩鹀(Emberiza godlewskii)4巢、褐顶雀鹛(Alcippe brunnea)3巢、褐胁雀鹛(A.dubia)7巢和黑颏凤鹛(Yuhina nigrimenta)1巢。对其巢、卵或雏鸟以及巢址等进行了描述。  相似文献   

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Between 1974 and 1978, 2,842 identifications of plant-parasitic nematodes were made from more than 1,700 soil and plant samples collected in eight provinces of South Viet Nam. Species in nine genera—Helicotylenchus, Criconemoides, Meloidogyne, Pratylenchus, Tylenchorhynchus, Hoplolaimus, Hirschmanniella, Xiphinema, and Rotylenchulus—comprised 96.1% of the identifications; the remaining 3.9% were species of 11 genera. Fourteen genera were associated with rice which was grown on about 2,500,000 ha in 1970. Of these, Ditylenchus, Hirschmanniella, and Meloidogyne were most important. Ditylenchus angustus caused severe damage to about 50,000 ha of flooded rice in the Mekong Delta in 1976. Hirschmanniella spp. were found in all samples examined from flooded rice fields. Meloidogyne spp. were common in rice seedbeds, upland rice, and rice not kept flooded continuously. Meloidogyne and Pratylenchus spp. were found in roots of 22 of the 32 crop plants sampled. Little or no attempt was made in South Viet Nam to control nematodes.  相似文献   

14.
An identification key for 20 common strand-forming indoor wood decay fungi is given. The key is based on observations of material from affected buildings and on wood samples that have been incubated in the laboratory. The key is with macro- and microscopic photographs.  相似文献   

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Mammals with more rapid and agile locomotion have larger semicircular canals relative to body mass than species that move more slowly. Measurements of semicircular canals in extant mammals with known locomotor behaviours can provide a basis for testing hypotheses about locomotion in fossil primates that is independent of postcranial remains, and a means of reconstructing locomotor behaviour in species known only from cranial material. Semicircular canal radii were measured using ultra high resolution X-ray CT data for 9 stem primates (“plesiadapiforms”; n = 11), 7 adapoids (n = 12), 4 omomyoids (n = 5), and the possible omomyoid Rooneyia viejaensis (n = 1). These were compared with a modern sample (210 species including 91 primates) with known locomotor behaviours. The predicted locomotor agilities for extinct primates generally follow expectations based on known postcrania for those taxa. “Plesiadapiforms” and adapids have relatively small semicircular canals, suggesting they practiced less agile locomotion than other fossil primates in the sample, which is consistent with reconstructions of them as less specialized for leaping. The derived notharctid adapoids (excluding Cantius) and all omomyoids sampled have relatively larger semicircular canals, suggesting that they were more agile, with Microchoerus in particular being reconstructed as having had very jerky locomotion with relatively high magnitude accelerations of the head. Rooneyia viejaensis is reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility.  相似文献   

18.
We dedicate this article to the memory of Sergio de Freitas, FCAV-UNESP, Jaboticabal, São Paulo, Brazil (deceased, 2012). He was an active and enthusiastic Neuropterist and the cherished mentor and friend of Francisco Sosa.Leucochrysa McLachlan is the largest genus in the Chrysopidae, yet it has received relatively little taxonomic attention. We treat two problematic and common Leucochrysa species – Leucochrysa (Leucochrysa) varia (Schneider, 1851) and Leucochrysa (Leucochrysa) pretiosa (Banks, 1910). Both are highly variable in coloration and were described before the systematic importance of chrysopid genitalia was recognized. Recent studies show that these species occur within a large complex of cryptic species and that they have accumulated a number of taxonomic problems. We identify new synonymies for each of the species–for Leucochrysa (Leucochrysa) varia: Leucochrysa (Leucochrysa) ampla (Walker, 1853), Leucochrysa internata (Walker, 1853), and Leucochrysa (Leucochrysa) walkerina Navás, 1913; for Leucochrysa (Leucochrysa) pretiosa: Leucochrysa (Leucochrysa) erminea Banks, 1946. The synonymy of Leucochrysa delicata Navás, 1925 with Leucochrysa (Leucochrysa) pretiosa is stabilized by the designation of a neotype. The following species, which were previously synonymized with Leucochrysa (Leucochrysa) varia or Leucochrysa (Leucochrysa) pretiosa, are reinstated as valid: Leucochrysa (Leucochrysa) phaeocephala Navás, 1929, Leucochrysa (Leucochrysa) angrandi (Navás, 1911), and Leucochrysa (Leucochrysa) variata (Navás, 1913). To help stabilize Leucochrysa taxonomy, lectotypes are designated for Allochrysa pretiosa and Allochrysa variata. Finally, Leucochrysa vegana Navás, 1917 is considered a nomen dubium.  相似文献   

19.
A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several “bona fide” strains representing all described species.  相似文献   

20.
Differential bacterial counts were made on the intestinal and caecal contents of chickens after inoculation with a standard dose of 320 000 freshly sporulated oocysts of Eimeria brunetti.  相似文献   

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