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1.
2012—2013年间,利用食团分析法对阿尔金山国家级自然保护区纵纹腹小鸮Athene noctua的食性进行分析。共分析343个纵纹腹小鸮食团,鉴定出353个猎物。以个体计,当地纵纹腹小鸮主要取食小型哺乳动物,占95.18%,其次为鸟类,占3.97%,也取食少量昆虫(0.85%)。生物量贡献则以小型哺乳动物为主,占99.35%。纵纹腹小鸮在夏季和冬季就可鉴定的取食动物种类比例组成而言,差异具有高度统计学意义(χ2=52.27,df=4,P0.01)。冬、夏两季纵纹腹小鸮取食哺乳动物的平均胫骨长度差异具有高度统计学意义(P0.01)。全年来看,纵纹腹小鸮取食哺乳动物的胫骨长度平均为19.45 mm±5.84 mm(n=194),主要取食Ⅱ级(10.01 mm~20.00 mm)和Ⅲ级(20.01 mm~30.00 mm)的猎物(分别为46.39%和48.45%)。保护区纵纹腹小鸮的食物生态位宽度以夏季最高(2.583),冬季最低(0.949)。研究结果表明纵纹腹小鸮是机会主义捕食者,根据生境中食物的可获得性改变食性。  相似文献   

2.
乌鲁木齐市区越冬期长耳鸮的食性分析   总被引:1,自引:0,他引:1       下载免费PDF全文
2009~2011年间,利用食团分析法对乌鲁木齐市越冬长耳鸮(Asio otus)的食性进行分析。3年累计收集长耳鸮食团683份,辨认出1 132只猎物。分析结果表明,长耳鸮在冬季共捕食小型哺乳类6种,鸟类2种。小家鼠(Mus musculus)是最常见的食物,占总捕食量的53.45%。小型哺乳类是长耳鸮的主要食物,它在食物组成中出现的总频率为88.16%,以生物量计,小型哺乳类占食物构成的95.13%。长耳鸮的食物组成年度间差异显著,与当地猎物资源多样性和可获得性密切相关,表明长耳鸮可能采用机会主义者的捕食策略。  相似文献   

3.
不同栖居地和越冬时期长耳鸮的食物组成   总被引:1,自引:0,他引:1  
通过分析2003—2006年连续3个冬季北京城区和城郊越冬长耳鸮的食团,研究了长耳鸮食物组成的时间与空间变化特征。每月收集1次长耳鸮食团,通过其内容物分析长耳鸮食物中的猎物种类和数量构成。结果表明:城区和城郊两地长耳鸮3种主要猎物中蝙蝠的被捕食率分别为41.6%和43.0%,鼠类为27.5%和39.4%,鸟类为30.7%和18.9%;城区和城郊长耳鸮的食物构成在2004—2005年与2005—2006年的冬季存在显著差异,初冬和冬末的食物构成差异也呈显著水平;同区域的长耳鸮食物构成在年度间和不同越冬时期皆存在显著差异;两地越冬长耳鸮捕食猎物比例的差异与生存环境中猎物资源的可获得性有关。  相似文献   

4.
在巴基斯坦对仓鸮食性的季节变化进行了研究。通过分析连续3年在6个地区搜集的2 360个仓鸮回吐食物团,发现其食物主要是小型哺乳动物(95.6 %)。其中,家(Suncus murinus)有最高的比例,达65.6%(冬季最多78%,夏季最少27%)。就生物量而言,小型哺乳动物占仓鸮食物总生物量的99% 。  相似文献   

5.
横斑腹小鸮(Athene brama)是巴基斯坦旁遮普中部农业生态系统中最常见但研究匮乏的猛禽。我们通过分析吐弃块(n=498)以了解其季节性和地域性食性变化。结果显示:小型哺乳类占所有食物生物量的98.4%,而昆虫类在数量上占据绝对优势(56.4%)。在小型哺乳类食物中,鼠类(38.8%)是稳定的食物成分。而在昆虫食物中,甲虫最多(42.8%)。横斑腹小亦捕食鼩鼱类(2.3%)和鸟类(1.7%)。昆虫类食物还有蟑螂(6.4%)、臭虫(3.3%)、蝗虫(6.7%)和蚂蚁(3.2%)。小家鼠(Mus musculus)和柔毛鼠(Rattus meltada)在鼠类食物中出现频次最多。不同地区中,Hafizabad的食物多样性最高(2.07),而秋季的食物多样性最高(1.99)。  相似文献   

6.
猞猁(Lynxlynx)是内蒙古赛罕乌拉国家级自然保护区内的顶级捕食者,在维持该地区生态平衡和调节猎物数量上具有重要地位。分析猞猁粪便样品残留物不仅能明确其猎物构成,了解与同域分布其他捕食者的关系,还能为制定物种保护措施和栖息地管理策略提供科学参考。本研究在2006至2008年间利用样线法在该区域收集到35份猞猁粪便样品。通过相对出现频率法对粪样进行食性分析,发现猞猁的主要食物组成以蒙古兔(Lepus tolai,30.85%)和植物(28.72%)较多;年度(χ~2=18.696,P 0.001)和季节性(χ~2=74.695,P 0.001)食物构成均存在显著差异。结果表明,蒙古兔在猞猁的食物组成中占最重要地位;猞猁的食物构成与季节有关,寒冷季节捕食大型猎物,而温暖季节捕食的小型猎物更常见。  相似文献   

7.
对2008年4~6月在甘肃省甘塘、阿拉善左旗、民勤、山丹采集的荒漠沙蜥样本进行了食物两性差异的研究。主要采用剖胃法对219个荒漠沙蜥胃样的6021个食物做了识别和鉴定。结果表明,荒漠沙蜥的食性为动物性,食物多为昆虫,主要取食半翅目和膜翅目昆虫,尤其是长蝽科和蚁科(合计高于70%),取食猎物的体积大小集中在0.01~20mm3。4个种群的沙蜥对长蝽科昆虫均表现为正向选择,部分种群对蚁科昆虫表现负向选择。可能是因为沙蜥有食物选择性,对长蝽科昆虫取食较多,对拟步甲科摄食较少。较多地取食蚂蚁则是因为生境中喜好食物较少,而蚁科昆虫数量多,遇见率也较高。荒漠沙蜥雌雄个体食物生态位重叠度极高,但是卡方检验的结果却表明两性在食物组成和食物大小存在显著差异。由于雌雄个体对同种食物有相同的选择性,因此导致两性在食物组成和食物大小上存在显著差异的原因可能是雄性家域范围更大,对食物有更多选择。  相似文献   

8.
普通大kuang胃容物和食茧分析   总被引:2,自引:0,他引:2  
对青海省玛多县境内的普通大kuang(Buteo hemilasius)的14个胃容物和118个食茧中的猎物逐个分析鉴定,共分为3种类型:①高原鼠兔(Ochotona curzoniae),②青海田鼠(Lasiopodomys fuscus),③小型鸟类。分别计算各类猎物出现率(pi)和生物量比率(bi)。高原鼠兔、青海田鼠、小型鸟类在胃容物中,pi分别为0.28、0.68和0.04;bi则分别为0.59、0.40和0.02;食茧中,pi分别为0.70、0.27和0.02,bi则分别为0.89、0.10和0.01。Χ[2]检验表明取食个体数和生物量在胃容物和食茧之间差异显著,但均说明高原鼠兔和青海田鼠等小型哺乳类是普通大的主要食物来源。  相似文献   

9.
北京市区越冬长耳的食性分析   总被引:1,自引:2,他引:1  
2004年11月至2005年4月,采用食团分析法对北京市区内天坛生物制药厂和国子监公园内栖息越冬的长耳鸮(Asiootus)的食物组成进行了分析。发现天坛生物制药厂长耳鸮的食物中啮齿类占41.0%,翼手类占29.5%,鸟类占29.3%,食虫类占0.2%;国子监长耳鸮的食物组成中翼手类占53.8%,啮齿类占21.5%,鸟类占24.7%。翼手目主要种类有山蝠(Nyctalus noctula)和普通伏翼(Pipistrellus abramus)等。长耳鸮三类主要食物所占比例的逐月变化显示,翼手类所占百分比不断上升,啮齿类所占比例先上升而到翌年1、2月开始下降,鸟类所占百分比一直在下降。蝙蝠大量出现于温带冬季鸮类的食物中属首次发现。  相似文献   

10.
湖北后河自然保护区果子狸食物组成初步研究   总被引:3,自引:0,他引:3  
2005年4~10月在湖北后河自然保护区,采集果子狸(Paguma larvata)粪便,应用频次法进行分析,再结合胃内容物分析,同时根据采食痕迹,对该物种春、夏和秋季的食物组成进行了研究。结果表明,果子狸食物组分以水果类植物(37·5%)、节肢动物(25·2%)为主,其次为非水果类植物(9·9%)和小型哺乳动物(7·1%)等。果子狸食物组成在不同的季节间有一定差异。春季,果子狸食物组成中以节肢动物(35·6%)为主,其次是非水果类植物(26·7%)和小型哺乳动物(15·6%),另外还有少量的软体动物(4·4%)和水果类植物(8·9%);夏季,果子狸食物组成转为以水果类植物(39·8%)和节肢动物(29·2%)为主,此外还有少量非水果类植物(2·7%)和小型哺乳动物(5·3%),以及少量鸟类(0·9%);秋季,果子狸食物组分中含有大量的水果类植物(63·9%),其他食物类别比例很小,包括鸟类(1·0%)、小型哺乳动物(0·6%)和爬行动物(0·4%)等。食物多样性指数显示,随着季节变化,果子狸食物多样性逐渐下降,小型哺乳动物和非水果类植物在其食性组成中逐渐下降,而水果类植物则转为最主要食物。  相似文献   

11.
12.
Growing prosperity in the South is accompanied by human diets that will claim more natural resources per capita. This reality, combined with growing populations, may raise the global demand for food crops two- to four-fold within two generations. Considering the large volume of natural resources and potential crop yields, it seems that this demand can be met smoothly. However, this is a fallacy for the following reasons. (i) Geographic regions differ widely in their potential food security: policy choices for agricultural use of natural resources are limited in Asia. For example, to ensure national self-sufficiency and food security, most of the suitable land (China) and nearly all of the surface water (India) are needed. Degradation restricts options further. (ii) The attainable level of agricultural production depends also on socio-economic conditions. Extensive poverty keeps the attainable food production too low to achieve food security, even when the yield gap is wide, as in Africa. (iii) Bio-energy, non-food crops and nature compete with food crops for natural resources. Global and regional food security are attainable, but only with major efforts. Strategies to achieve alternative aims will be discussed. <br>  相似文献   

13.
Intrauterine sensitization caused by food allergens plays an important role in the food allergy development in progeny. The aim of our study was to determine the critical period of intrauterine sensitization during pregnancy. Female mice were exposed to ovalbumin (OVA) during different trimesters of pregnancy. Lymphocytes from their offspring were isolated and cultured, and proliferation was evaluated by CCK-8 assay. The levels of IFN-γ and IL-4 in serum were measured using ELISA. In addition, the expressions of IFN-γ and IL-4 mRNAs and proteins were detected by real-time PCR and western blot. The mice were divided into the first trimester pregnancy (FTP1 and FTP2) group, the second trimester pregnancy (STP1 and STP2) group, and the third trimester pregnancy (TTP1 and TTP2) group based on the stages of pregnancy in which their mothers were exposed to OVA and their ages. The OVA-specific lymphocyte proliferation of the TTP1 group was statistically significantly greater that in the FTP1 and STP1 groups. The serum level of IFN-γ in the TTP1 group was significantly decreased, and the serum level of IL-4 in the TTP1 group was significantly increased compared with the levels in the FTP1 and STP1 groups. The mRNA and protein expression levels of IFN-γ in the TTP1 group were significantly decreased and the mRNA and protein expression levels of IL-4 in this group were significantly increased compared with the levels in the FTP1 and STP1 groups. Our results suggest that OVA-induced intrauterine sensitization in the third trimester may increase the risk of food allergy after birth.  相似文献   

14.
It has been suggested that two endogenous timekeeping systems, a light-entrainable pacemaker (LEP) and a food-entrainable pacemaker (FEP), control circadian rhythms. To understand the function and interaction between these two mechanisms better, we studied two behavioral circadian rhythmicities, feeding and locomotor activity, in rats exposed to two conflicting zeitgebers, food restriction and light-dark cycles. For this, the food approaches and wheel-running activity of rats kept under light-dark (LD) 12:12, constant darkness (DD), or constant light (LL) conditions and subjected to different scheduled feeding patterns were continuously recorded. To facilitate comparison of the results obtained under the different lighting conditions, the period of the feeding cycles was set in all three cases about Ih less than the light-entrained or free-running circadian rhythms. The results showed that, depending on the lighting conditions, some components of the feeding and wheel-running circadian rhythms could be entrained by food pulses, while others retained their free-running or light-entrained state. Under LD, food pulses had little influence on the light-entrained feeding and loco-motor rhythms. Under DD, relative coordination between free-running and food-associated rhythms may appear. In both cases, the feeding activity associated with the food pulses could be divided into a prominent phase-dependent peak of activity within the period of food availability and another afterward. Wheel-running activity mainly followed the food pulses. Under LL conditions, the food-entrained activity consisted mainly of feeding and wheel-running anticipatory activity. The results provide new evidence that lighting conditions influence the establishment and persistence of food-entrained circadian rhythms in rats. The existence of two coupled pacemakers, LEP and FEP, or a multioscillatory LEP may both explain our experimental results.  相似文献   

15.
It has been suggested that two endogenous timekeeping systems, a light-entrainable pacemaker (LEP) and a food-entrainable pacemaker (FEP), control circadian rhythms. To understand the function and interaction between these two mechanisms better, we studied two behavioral circadian rhythmicities, feeding and locomotor activity, in rats exposed to two conflicting zeitgebers, food restriction and light-dark cycles. For this, the food approaches and wheel-running activity of rats kept under light-dark (LD) 12:12, constant darkness (DD), or constant light (LL) conditions and subjected to different scheduled feeding patterns were continuously recorded. To facilitate comparison of the results obtained under the different lighting conditions, the period of the feeding cycles was set in all three cases about Ih less than the light-entrained or free-running circadian rhythms. The results showed that, depending on the lighting conditions, some components of the feeding and wheel-running circadian rhythms could be entrained by food pulses, while others retained their free-running or light-entrained state. Under LD, food pulses had little influence on the light-entrained feeding and loco-motor rhythms. Under DD, relative coordination between free-running and food-associated rhythms may appear. In both cases, the feeding activity associated with the food pulses could be divided into a prominent phase-dependent peak of activity within the period of food availability and another afterward. Wheel-running activity mainly followed the food pulses. Under LL conditions, the food-entrained activity consisted mainly of feeding and wheel-running anticipatory activity. The results provide new evidence that lighting conditions influence the establishment and persistence of food-entrained circadian rhythms in rats. The existence of two coupled pacemakers, LEP and FEP, or a multioscillatory LEP may both explain our experimental results.  相似文献   

16.
免疫分析新方法在食品安全检测中的应用   总被引:1,自引:0,他引:1  
免疫分析技术具有特异性强、灵敏度离、方便快捷、检测成本低、安全可靠等优点,已成为现代生命科学的重要研究手段,在食品安全检测中有着良好的应用前景。本文综述了近几年来出现的免疫分析新方法,简单介绍了它们在食品安全检测中的应用。  相似文献   

17.
Petroleum and natural gas are the primary fuels in the US food system. Both fuels are now in short supply and significant quantities are being imported into the USA from various nations. An investigation documented that fossil energy use in the food system could be reduced by about 50% by appropriate technology changes in food production, processing, packaging, transportation, and consumption. The results suggest that overall, farmers benefit as well as consumers.  相似文献   

18.
生物工程技术在食品工业领域中的应用   总被引:1,自引:0,他引:1  
据当今生物工程技术发展情况,综述了它在食品工业领域中的食用资源开发、食品加工及食品安全检测中的应用.  相似文献   

19.
海南变色树蜥个体发育中形态和食性的变化   总被引:7,自引:1,他引:6       下载免费PDF全文
研究变色树蜥(Calotes versicolor)头,尾大小和食性在个体发育过程中的变化,以及头,尾大小两性异性的个体发生,成体体长(SVL)无显著的两性差异,两性异形主要表现为雄性个体有较大的头部(头长和头宽)和尾部。头,尾大小的两性异形在初生幼体就已存在,并随个体发育的进行变得更加显著。不同年龄组两性个体头长以及雌体头宽随SVL呈同速增长;雄性头宽随SVL呈异速增长,表现为雄性头宽的增长速率在个体发育过程中逐渐增大。头,尾部的相对大小在个体发育过程中有显著的变化,初生幼体头部相对较大,尾部相对较小,这种形态特征是胚胎优先保证生态学意义更为显著的部分(如头部)生长的结果,有利于初生幼体的早期生存和生长,不同性别和年龄组的变色树蜥摄入食物的种类及各种食物在摄入食物中所的比例有一定程度的差别,因而食物生态位宽度和重叠度有一定程度的差别,然而没有直接的证据表明头部大小的两性异形能导致两性食物生态位的明显分离。  相似文献   

20.
The rising need for wholesome, fresh, safe and “minimally-processed” foods has led to pioneering research activities in the emerging non-thermal technology of food processing. Cold plasma is such an innovative and promising technology that offers several potential applications in the food industry. It uses the highly reactive, energetic and charged gas molecules and species to decontaminate the food and package surfaces and preserve the foods without causing thermal damage to the nutritional and quality attributes of food. Cold plasma technology showed promising results about the inactivation of pathogens in the food industry without affecting the food quality. It is highly effective for surface decontamination of fruits and vegetables, but extensive research is required before its commercial utilization. Recent patents are focused on the applications of cold plasma in food processing and preservation. However, further studies are strongly needed to scale up this technology for future commercialization and understand plasma physics for getting better results and expand the applications and benefits. This review summarizes the emerging trends of cold plasma along with its recent applications in the food industry to extend shelf life and improve the quality of food. It also gives an overview of plasma generation and principles including mechanism of action. Further, the patents based on cold plasma technology have also been highlighted comprehensively for the first time.  相似文献   

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