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1.
不同生活条件下东方田鼠内脏器官比较   总被引:9,自引:1,他引:8  
脏器指数可以反映动物的生理功能 ,消化道形态的变化受食物质量和动物能量需求的影响 ,国内外不少学者探讨了野外条件下鼠类脏器指数和消化道形态的季节变化及其生态适应意义[2 ,4 ,6~ 8,14 ,15] 。Gross等[12 ] 在室内研究了温度和食物质量对草原田鼠 (Microtusochrogaster)消化道形态的影响。东方田鼠 (M .fortiscalamorum )为洞庭湖湖泊河汊区优势鼠种 ,严重危害农林业生产 ;同时其具有天然抗日本血吸虫的特性[13] ,对血吸虫的研究和防治有着较为重要的意义。该鼠以湖滩苔草(Carexspp …  相似文献   

2.
植物生长季节不同栖息地高原鼠兔的食物选择   总被引:4,自引:2,他引:2  
本文采用胃内容物镜检分析法,对栖息于青藏高原矮嵩草草甸、垂穗披碱草草甸和杂类草草甸中的高原鼠兔的主要食物组成进行了比较分析,旨在探讨栖息地变化对高原鼠兔食物组成的影响,揭示高原鼠兔对栖息地变化的生存对策和适应性.研究结果表明:在矮嵩草草甸,高原鼠兔主要取食垂穗披碱草、早熟禾、蓝花棘豆和甘肃棘豆;在垂穗披碱草草甸,主要选择垂穗披碱草、甘肃棘豆、蓝花棘豆、矮嵩草和二柱头蔗草;在杂类草草甸,喜食植物种类为垂穗披碱草、蓝花棘豆、甘肃棘豆、早熟禾、弱小火绒草、长茎藁本、兰石草和红花岩生忍冬.在整个植物生长季节,高原鼠兔在3种栖息地共取食27种植物,其中垂穗披碱草、甘肃棘豆和蓝花棘豆在不同栖息地中选择指数较高,为高原鼠兔优先选择的食物;在不同栖息地,高原鼠兔取食植物有差别,垂穗披碱草草甸为16种、矮嵩草草甸为22种,杂类草草甸为24种;喜食食物比例也存在着明显差别,在垂穗披碱草草甸,垂穗披碱草比例高达40.5%,在矮嵩草草甸,甘肃棘豆比例也达到23.7%,而在杂类草草甸,选食比例最高的兰石草仅为14.6%,说明在该草甸高原鼠兔食物选择呈现泛化趋势.相似性指数分析结果也表明,杂类草草甸中高原鼠兔主要食物组成与其它两种栖息地有较大的区别.从而说明当栖息地植物群落种类组成发生变化后,高原鼠兔可以通过改变其食物组成而适应新的栖息地.  相似文献   

3.
壶瓶碎米荠(Cardamine Hupingshanesis)胚和胚乳发育的研究   总被引:1,自引:0,他引:1  
壶瓶碎米荠(Cardamine Hupingshanesis.)是十字花科中以营养体繁殖的多年生植物,在自然条件下,种子不易萌芽成苗。本文以碎米荠、油菜为对照材料对壶瓶碎米荠的胚胎发育进行了观察。壶瓶碎米荠胚发育经球形胚、心形胚、鱼雷形胚和子叶胚四个时期,属柳叶菜型。胚乳发育属核型发育类型,其胚胎发育过程和成熟胚结构与节状聚积和胚乳吸器,而壶瓶碎米荠和碎米荠无此类结构。通过胚胎发育观察证明,壶瓶碎米荠种胚结构完整,其种子不易萌发成苗可能与其特殊的生理原因有关。  相似文献   

4.
布氏田鼠对主要贮草种类的选储嗜好   总被引:2,自引:0,他引:2  
布氏田鼠 (Microtusbrandti)为内蒙古典型草原区的主要害鼠 ,其危害主要表现在与牲畜争夺牧草资源[1,3 ,5,6,9] 。该鼠属不冬眠种类 ,冬季主要以洞群贮草仓库中的贮草为食 ,因此 ,研究其秋季集群的贮草习性 ,对于分析和了解该鼠的越冬生态特征具有一定的意义。有关布氏田鼠的贮草习性 ,已有一些报道[4 ,7] 。研究表明 ,在羊草 冷蒿 隐子草草场 ,布氏田鼠的越冬贮草以蒿属 (Artemisia)植物为主 ,其中冷蒿 (A .frigida)与黄蒿 (A .scoparia)占贮草比例超过 90 % [2 ] ,但上述研究均未涉及布氏田鼠…  相似文献   

5.
高原鼠兔冬季的食物选择   总被引:3,自引:1,他引:2  
本文采用胃内容物镜检分析法,对高原鼠兔在矮嵩草草甸、垂穗披碱草草甸和杂类草草甸三种类型栖息
地中的主要食物组成进行了比较分析,旨在探讨三类栖息地不同食物资源状况对高原鼠兔食物组成的影响,以
及高原鼠兔在食物匮乏的冬季的觅食对策。研究结果表明:高原鼠兔在冬季主要选食弱小火绒草和铺散亚菊,
甘肃棘豆、垂穗披碱草和长茎藁本也是冬季食物主要组成部分。在冬季食物资源较为匮乏的情况下,高原鼠兔
选食的主要植物种类相对较多,且不同植物比例变化明显,说明高原鼠兔对食物具有一定的选择性。在矮嵩草
草甸中,其食物组成依次为铺散亚菊(16. 2% ) > 弱小火绒草(11. 5% ) > 甘肃棘豆(11. 3% ) > 大籽蒿
(9. 7% ) > 早熟禾(7. 6% ) > 长茎藁本(7. 5% ) > 垂穗披碱草(5. 5% )等7 种,占其食物的69. 3% ;在垂
穗披碱草草甸,其主要食物组成依次为垂穗披碱草(15. 8% ) > 甘肃棘豆(14. 7% ) > 弱小火绒草(14. 5% )
> 铺散亚菊(14. 2% ) > 早熟禾(7. 8% ) > 长茎藁本(6. 9% ) > 锥果葶苈(6. 2% )等7 种,占其食物的
80. 1% ;在杂类草草甸中,其主要食物组成依次为铺散亚菊(20. 8% ) > 长茎藁本(20. 6% ) > 大籽蒿
(9. 9% ) > 弱小火绒草(9. 8% ) > 锥果葶苈(6. 5% ) > 圆齿狗娃花(5. 5% )等6 种,占选食食物的73. 1% 。
不同栖息地之间食物组成比较分析结果表明,在冬季食物资源匮乏的情况下,栖息地类型不同对高原鼠兔食物
组成的影响较小,杂类草构成了它们的主要食物,这可能是由食物质量决定的,而不同栖息地中喜食植物可利
用量是决定鼠兔食物组成的主要因子,进一步验证了食物可利用量和质量决定植食性小哺乳动物食物选择模式
的假设。  相似文献   

6.
大叶碎米荠为十字花科碎米荠属多年生草本植物,作为药食同源蔬菜,具有通尿利便、止痛及治败血病等药效。异硫氰酸盐是存在于十字花科植物中的一种具有防癌抗癌作用的有机硫化合物。本研究用二氯甲烷从大叶碎米荠水解液中提取出硫代葡萄糖苷水解产物,经气相-质谱联用分析其组分,鉴定出2种异硫氰酸盐化合物,分别为异硫氰酸烯丙酯和异硫氰酸甲硫基烯丙酯,两者的含量分别为2.32 mg/kg、0.50 mg/kg。该研究为大叶碎米荠作为野菜资源开发利用提供了科学依据。  相似文献   

7.
苔草属植物柄锈菌3个新种和2个中国新记录种,它们是:寄生在点叶苔草CarexhancockianaMaxim.上的点叶苔草柄锈菌(新种)Pucciniacaricis-hancockianaeJ.Y.Zhang&S.X.Weisp.nov,寄生在十字苔草CarexcruciataWahlenb.上的海南柄锈菌(新种)PucciniaahainanensisJ.Y.Zhuang&S.XWeisp.n  相似文献   

8.
湖北斧头湖湖滨湿地水田碎米荠群落的定量分析   总被引:3,自引:0,他引:3  
李伟  钟扬 《水生生物学报》1995,19(3):250-256
本文对湖北武昌斧头湖湖滨湿地的一个常见群落-水田碎米荠群落进行了详细分析。群落中出现了16种植物,它们的频率分布与Raunkiaer频率分布定律稍有差异。水田碎米荠和荇菜是群落的主要优势种。该群落垂直结构较为简单,大部分区域可区分出两个植被层。不同物种的分布反映了它们对微地形变化的适应。所有的主要常见种均表现出群聚分布的格局,结合分析揭示了一些植物在不同区组规模上的相关。  相似文献   

9.
西藏马鹿如何适应草枯期高海拔环境是其维持营养摄入所面临的挑战之一。深入研究草枯期植物群落随海拔变化规律以及二者变化如何影响西藏马鹿食物组成是开展高原生态系统野生大型有蹄类营养生态学研究的重要基础。本研究以西藏山南地区桑日县西藏马鹿种群为对象,于2021年3月和2022年3月青藏高原草枯期,对西藏马鹿种群出现点的海拔、植物群落和采食痕迹开展野外调查,通过去趋势对应分析和典范对应分析分别研究植物群落随海拔变化的特点和西藏马鹿食物组成随海拔变化的规律。结果表明:西藏马鹿草枯期食物组成主要包括褐背柳、腺果大叶蔷薇和小叶金露梅等,其中褐背柳的采食比例超过50%,为草枯期西藏马鹿重要食物来源;在低海拔区域(4100~4300 m),植物群落主要包括变色锦鸡儿、腺果大叶蔷薇和西藏沙棘等,西藏马鹿主要以腺果大叶蔷薇、变色锦鸡儿和藏沙蒿为食物;在高海拔区域(4300~4600 m),植物群落由雪层杜鹃、草莓花杜鹃和窄叶鲜卑花等组成,西藏马鹿主要以褐背柳、毛坡柳、康藏嵩草等为食物。西藏马鹿在不同海拔均以植物群落优势种为主要食物,表明植物群落组成随海拔的变化直接影响西藏马鹿的食物组成,即西藏马鹿随海拔变化具...  相似文献   

10.
周世良  潘开玉  洪德元   《广西植物》1999,19(2):176-179
报道了杭州石荠(MoslahangchouensisMatsuda)的种子散布机制和特点,结合其它方面的研究结果,为迁地保护提供理论依据。杭州石荠小坚果的散布机制是被动弹力散布,植株、花萼和小坚果三者联合参与,风、雨、动物触动是能量来源。初级散布距离在实验条件下,在30~35cm的区域小坚果最多,此后,随面积的增加而减少,密度峰值出现在10~15cm的区间。杭州石荠的小坚果表面具旋涡状凹陷,凹陷中有细密的突起,这种结构有一定的拒水性,下沉速率小,适于以水为载体的次级散布,也具有较强的保水抗旱能力,能够确保杭州石荠在干旱的生境中世代延续。作者认为,杭州石荠的分布特性和比较特殊的生物学和生态学特点限制了居群的扩展是其濒危的重要原因。  相似文献   

11.
A sequence of trawl surveys showed that the diet of plaice off eastern Anglesey was dominated by Abra alba in spring and summer, and by Pectinaria koreni in early spring and autumn. Plaice ate little food in winter. Despite the relatively small stomach in this species, plaice were able to achieve high rates of daily food intake during bouts of heavy feeding by rapidly transferring newly-ingested prey items into the anterior intestine without full gastric digestion. Seasonal daily feeding rates (percentage body weight) varied between 5 and 10% for small fish (15–20 cm total length), 3 and 12% for medium fish (20–25 cm) and 2.8 and 4.4% for large fish (30–35 cm).  相似文献   

12.
Fey K  Banks PB  Korpimäki E 《Oecologia》2008,157(3):419-428
Ecosystems of three trophic levels may be bottom-up (by food-plant availability) and/or top-down (by predators) limited. Top-down control might be of greater consequence when the predation impact comes from an alien predator. We conducted a replicated two-factor experiment with field voles (Microtus agrestis) during 2004-2005 on small islands of the outer archipelago of the Baltic Sea, south-west Finland, manipulating both predation impact by introduced American mink (Mustela vison) and winter food supply. In autumn 2004, we live-trapped voles on five islands from which mink had been consistently removed, and on four islands where mink were present, and provided half of these islands with 1.8 kg oats per vole. Body mass of female voles increased as a response to supplementary food, whereas both food supplementation and mink removal increased the body mass of male voles in subsequent spring. During winter, there was a positive effect of supplementary food, but in the subsequent summer, possible positive long-term impacts of food supplementation on field voles were not detected. Mink removal appeared not to affect density estimates of field voles during the winter and summer immediately after food addition. Trapping data from 2004 to 2005 and 2007 suggested, however, that in two out of three summers densities of voles were significantly higher in the absence than in the presence of mink. We conclude that vole populations on small islands in the archipelago of the Baltic Sea are mainly bottom-up limited during winter (outside the growing season of food plants), when food availability is low, and limited by mink predation during summer which slows population growth during the reproductive season of voles.  相似文献   

13.
Previous studies of Trachypithecus species indicated that they were selective feeders that concentrated on relatively few food species/items. From January to December 2005, I quantified potential food availability and the food species/items eaten by five groups of François' langur (Trachypithecus francoisi) in the Mayanghe Nature Reserve (MNR), People's Republic of China. These langurs fed on 164 species, of which the top ten accounted for 51% of all feeding records. Langurs consumed more species (91) in the spring than in other seasons (73 summer, 75 autumn, and 67 winter), and only 38 species were consumed in all seasons. Nontree food species, such as bushes and lianas, accounted for 47% of the total feeding records and for a majority (68%) of the feeding records in winter. The annual diet consisted of leaves (64% of feeding records), fruit and seed (32%), and other nonfoliage items (4%); the langurs switched from being more folivorous in spring (93%) and summer (79%) to being more frugivorous in autumn (53%) and winter (56%). There was no correlation between the proportion of feeding records and the food availability in the most frequently consumed species, indicating that these langurs were selective feeders; there were significant correlations between consumption and abundance in both the entire set of 112 food species and the set of 86 infrequently consumed species, indicating that foods that are more available are eaten more frequently. It appeared that in the seasonal and disturbed habitat, feeding decisions and diet composition of the langur may be driven more by food availability, and less by animal's selectivity, than at other sites. The results indicate that François' langur copes with habitat alterations by broaden its dietary breadth; this has implications for the adaptive significance of dietary breadth, and has implications for future conservation strategies for species which exist in degraded habitats. Am. J. Primatol. 73:1176–1187, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

14.
Autumn and winter predation on bank vole Clethrtonomys glareolus and yellow-necked mouse Apodemus flavicollis was studied in 1985/86-88/89 in an 11 2 km2 area of the Bialowieza National Park Rodents regularly increased in numbers from spring to autumn and decreased throughout winter Out of 23 species of predators, the most common were tawny owl Strix aluco (43-57 adult ind 10 km−2) weasel Mustela ntvahs (17-27 ind), buzzard Buteo buteo (12-16) and pine marten Martes martes (5-8) Voles and mice were the staple food for two specialists the stoat Mustela erminea and the weasel, and two generahsts the tawny owl and the pine marten The generalists exploited different alternative prey when rodents were scarce tawny owl -amphibians, marten - small mammals, and the red fox Vulpes vulpes - ungulate carcasses and hares The depth of snow and abundance of voles were two major factors shaping the contribution of voles to tawny owl and marten diets No such relationships were found for mice and generalist predators The predation by 8 species (tawny owl, buzzard, marten, weasel, stoat, polecat Mustela putortus fox, and raccoon dog Nyctereutes procyonoides) from 1 October to 15 April in 1986/87, 87/88, and 88/89 was estimated to be on average 28-35 voles and 14-17 mice ha Estimates suggested that three species were responsible for 86-95% of the total predation impact tawny owl (56-71%), weasel (11-21%) and marten (10-15%) The predation impact was similar to the annual decrease in rodent numbers from autumn till spring voles 35 (SD 111) lnds ha-1in autumn and 8 (SD 2 6) lnds ha-1in spring, and mice 24 (SD 16 3) mds ha−1 in autumn and 3 (SD 2 5) in spring Predation, therefore, was regarded as the main agent of rodent mortality throughout autumn and winter  相似文献   

15.
Between December 1974 and November 1975 (157 days), it was found that seasonal home range changes in the Shiga C troop were closely related to food changes, vegetation, and the existence of neighbouring troops. The detailed points clarified may be summarized as follows: (1) The seasonal home range sizes from winter to autumn were 1.23 km2, 1.46 km2, 1.69 km2, and 1.21 km2, respectively, and the annual size was 3.66 km2; (2) The food changed from bark and buds of trees in winter to young leaves and stems of grasses and trees in spring and summer, and fruits in autumn; (3) Each home range clearly changed according to the phenology of the plants used as food at each season; (4) The food abundance for the monkeys was extremely poor in winter, relatively poor in summer, plentiful in spring, and the best in autumn; and (5) The Shiga C troop and the neighbouring Shiga B2 troop overlap in their home ranges in spring and autumn, but are separated during winter and summer.  相似文献   

16.
Cardamine hirsuta is a European species that was recently introduced into Japan and its wide distribution has been confirmed in the Kanto district. To understand mechanisms of the recent spread of C. hirsuta in Japan, a comparative study of the alien species and its native congeneric species, C. flexuosa, was conducted. Habitat preferences, phenology and seed germination were examined. Cardamine hirsuta and C. flexuosa showed distinctive habitat-preferences; the former was most common in open habitats created by recent man-made constructions, and the latter was common in rice paddy fields and surrounding areas. The results indicate that C. flexuosa is a year-long annual, with a mixed phenology of summer and winter germination and growth. Seed dormancy during summer was relatively weak for C. flexuosa, and some plants that germinated early in summer reproduced during the same summer–autumn period. Plants that germinated in late summer and autumn behaved as winter annuals. In rice paddy fields, C. flexuosa is a winter annual because germination is prevented by submergence during summer. Plants flower during the following spring and complete their life cycle before the fields are flooded for rice cultivation. Cardamine hirsuta showed strong seed dormancy during summer and behaved as a typical winter annual. Seeds of C. hirsuta were intolerant to submergence in water, a condition that breaks seed dormancy of C. flexuosa. The results explain the absence of C. hirsuta from rice paddy fields. It was concluded that the spread of C. hirsuta is attributable to the recent expansion of urban habitats created by human activity and has occurred without direct competition with C. flexuosa. Considering recent urbanization in many areas, it is suggested that C. hirsuta has been spreading rapidly in Japan.  相似文献   

17.
We collected data on diet and daytime activity budget, and investigated the phenology of food trees and food abundance for a group of Rhinopithecus roxellana on the East Ridge of Yuhuangmiao in the Qinling Mountains from November 2001 to December 2003. We calculated the seasonal activity budget using data collected by scan sampling from 84 full-day observations (winter 16, spring 18, summer 28, autumn 22 days). During scan sampling we recorded behavioral states, and the food items and species consumed. The subjects consumed 84 plant species, including trees and shrubs of 29 families, and lichens. Food species varied seasonally. The overall diet of R. roxellana consisted of 29.4% fruit/seeds, 29.0% lichens, 24.0% leaves, 11.1% bark, 4.2% buds, 1.3% twigs and 1.0% unidentified items. Because the abundance of different food items varied seasonally, the monkeys had to shift their major food items seasonally. The annual activity budget of R. roxellana was 36.2% time spent resting, 35.8% feeding, 22.9% moving, and 5.1% other behavior. Seasonal changes in activity budget were observed. R. roxellana spent more time moving in autumn, when the quality of the food might be highest, and least time moving in winter when the food quality might be lowest. Thus, this type of monkey has a passive foraging strategy.  相似文献   

18.
? Premise of the study: Viola hondoensis is a perennial herb that inhabits the understory of temperate, deciduous forests. It is an evergreen plant with a leaf life span that is shorter than a year. Its summer leaves are produced in spring and shed in autumn; winter leaves are produced in autumn and shed in spring. Here we asked why the plant sheds its winter leaves in spring, though climate conditions improve from spring to summer. We proposed four hypotheses for the cause of shedding: (1) changes in seasonal environment such as day length or air temperature, (2) shading by canopy deciduous trees, (3) self-shading by taller summer leaves, and (4) competition for nutrients between summer and winter leaves. ? Methods: To test these hypotheses, we manipulated the environment of winter leaves: (1) plants were transplanted to the open site where there was no shading by canopy trees. (2) Petioles of summer leaves were anchored to the soil surface to avoid shading of winter leaves. (3) Sink organs were removed to eliminate nutrient competition. ? Key results: Longevity of winter leaves was extended when shading by summer leaves was eliminated and when sink organs were removed, but not when plants were transplanted to the open site. ? Conclusion: We conclude that the relative difference in light availability between summer and winter leaves is a critical factor for regulation of leaf shedding, consistent with the theory of maximization of the whole-plant photosynthesis.  相似文献   

19.
洞庭湖区社鼠消化道长度和质量的季节变化   总被引:2,自引:0,他引:2  
对洞庭湖区社鼠(Niviventer confucianus)自然种群四季的消化道各器官的长度和质量进行了测定。结果表明。消化道指标季节变化明显。总体消化道含内容鲜质量、净鲜质量与干质量均具有显著的季节变化。以冬、春季较高。夏、秋季较低。消化道各器官的变化与总消化道不尽相同。其中,以胃的变化相对比较稳定。仅长度的变化达显著水平,以冬季最短,夏、秋季较长。这是动物为适应繁殖季节能量需求而增加摄食量的反应,也与夏秋季食物丰富度有关。小肠、盲肠、大肠的长度和质量指标(内容鲜质量、净鲜质量和干质量)以冬、春季较高。夏、秋季较低。这是该鼠对冬、春季低温和食物匮乏的适应性反应。总体来说。洞庭湖区社鼠为适应夏、秋季繁殖盛期能量需求增加的主要对策是增加摄食量;而为适应冬、春季低温环境和食物数量和质量减少的主要对策是增大消化道。提高消化效率。  相似文献   

20.
黑线仓鼠的食物与食量   总被引:6,自引:0,他引:6  
王淑卿  许同钦 《动物学报》1992,38(2):156-164
作者从1983年至1989年,在河北省三个不同的气候区,对农田中的黑线仓鼠(Cricetulus,bara-bensis)的食物与食量进行了调查。结果表明,黑线仓鼠主要取食农作物种子。同时取食草籽和根、茎、叶、花、果实及动物性食物。不同地区、不同作物地、不同季节和年度、不同性别鼠的食物差异显著。食物差异与鼠的种群繁值及数量动态有关。月夹捕率与颊囊中食物的总检出率和种子检出率正相关非常显著。直线回归方程式分别为y=38.388+2.866x n=60 r=0.343>r_(0.01)=0.325和y=29.734+2.669x r=0.394>r_(0.01360)=0.325。黑线仓鼠对食物的选择,主要受到食物质量的影响,同时也受到食物频度、作物的物候变化、动物的群落结构、种群密度、种内与种间竞争等多种因素的综合影响。在不同的时间和栖息地影响它食物选择的主要因素不同。日食量4-5g。  相似文献   

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