四川栗子坪自然保护区夏季大熊猫食性与主食竹生物量的关系

<正>竹子是大熊猫(Ailuropoda melanoleuca)的主要食物,是大熊猫赖以生存的物质基础(胡锦矗等,1985;胡锦矗,2001)。竹子生物量对大熊猫觅食乃至生存、繁衍等具有至关重要的影响。然而,竹子生物量随竹子种类、竹株部位和龄级以及生长环境的不同而可能具有明显差异(胡锦矗,1981;魏辅文等,1996)。截止目前,田星群(1989)等对秦岭大熊猫分布区的竹类资源进行了调查,黄华梨和杨飞虞(1990)、胡杰等(2000)分别对岷山山系大熊猫栖息地内竹子种类、主食竹     

巴山木竹发笋和大熊猫取食的时空格局及相关性分析

巴山木竹(Bashania fargesii)是秦岭大熊猫冬季和春季主要食物来源。秦岭地区巴山木竹的更新是保护大熊猫和评价其生境质量的一个重要因子, 而发笋是巴山木竹更新的主要方式。揭示巴山木竹发笋和大熊猫取食的时空格局以及二者空间和数量上的相关性对保护和恢复大熊猫栖息地具有重要意义。运用单变量和双变量Ripley K函数点格局方法, 对秦岭南坡佛坪国家级自然保护区40×40 m永久样地竹子发笋和大熊猫取食情况连续6年(2002–2008年, 2007年除外)研究表明, 由于自身克隆生长、资源异质性、大熊猫取食和践踏等因素, 巴山木竹发笋呈现聚集分布格局; 而大熊猫取食的聚集格局可能归因于食物聚集分布、自身取食习惯和取食地段小地形特征。大熊猫取食和巴山木竹发笋空间上呈现正相关, 显示出巴山木竹为秦岭大熊猫食物主要来源。同时, 线性回归结果显示, 大熊猫取食强度与巴山木竹发笋产量之间相关性不显著, 说明该地区还存在其他竹子提供食物来源, 大熊猫对巴山木竹不是完全依赖。     

用间接遥感方法探测大熊猫栖息地竹林分布

竹子是野生大熊猫赖以生存的唯一食物。探测大熊猫栖息地内的竹林分布状况,有助于深入了解大熊猫及其栖息地的空间分布格局与特点,并为评估其栖息地适宜性、破碎化程度和生态承载力提供科学依据。由于大熊猫的主食竹大都生长于林下,直接通过遥感影像解译的方法很难实现对其分布密度的探测。以佛坪自然保护区的两大优势竹种——巴山木竹和秦岭箭竹为例,在运用遥感和GIS方法获取空间连续的环境变量时,引入了林上和林下的光照条件,通过分析不同竹种与各环境要素之间的关系,建立竹子密度的预测模型,最后在GIS空间分析技术的支持下实现了对林下竹子密度的绘制。研究结果显示:该方法能够比较准确地预测出林下竹子的分布状态,对两种竹子的密度预测精度均可达到70%以上。     

秦岭大熊猫冬春季节对巴山木竹竹林生长指标的选择

2004~2005年冬季的12月、1月和春季的4月、5月,在秦岭山系南坡佛坪自然保护区内就大熊猫对构成其主要栖息地和食物来源的巴山木竹竹林的选择进行研究后的结果表明:在冬季,大熊猫栖息地多为幼竹与死竹比例基本持平、密度稳定的巴山木竹竹林,主要取食老竹;在春季,大熊猫更偏好选择竹子密度和盖度略低、竹子粗壮高大、幼竹与竹笋比例高的竹林活动,主要取食幼竹。大熊猫春季栖息地幼竹比例通常高过死竹比例,竹林密度处于增长期。竹林进入发笋期后,稀疏、高大的竹林下的粗大竹笋成为大熊猫的主要食物来源。     

秦岭大熊猫冬春季节对巴山木竹竹林生长指标的选择

2004～2005年冬季的12月、1月和春季的4月、5月，在秦岭山系南坡佛坪自然保护区内就大熊猫对构成其主要栖息地和食物来源的巴山木竹竹林的选择进行研究后的结果表明：在冬季，大熊猫栖息地多为幼竹与死竹比例基本持平、密度稳定的巴山木竹竹林，主要取食老竹；在春季，大熊猫更偏好选择竹子密度和盖度略低、竹子粗壮高大、幼竹与竹笋比例高的竹林活动，主要取食幼竹。大熊猫春季栖息地幼竹比例通常高过死竹比例，竹林密度处于增长期。竹林进入发笋期后，稀疏、高大的竹林下的粗大竹笋成为大熊猫的主要食物来源。     

秦岭大熊猫栖息地巴山木竹生物量

巴山木竹是秦岭大熊猫冬、春季食物的主要来源,其生长状况、数量和空间分布格局与大熊猫的生存与活动有着密切的关系。为了探讨不同立地因子对巴山木竹生物量的影响,确定巴山木竹生长的主导因子和适宜立地条件,在秦岭大熊猫栖息地内选取54块样地,对不同立地条件下巴山木竹生物量进行了测定。通过统计分析,结果表明:由于不同地区气候和土壤条件的差异,导致了巴山木竹生物量亦存在较大差别;巴山木竹生物量在其分布区内随海拔的升高而呈规律性变化,1500—1700 m为最适分布区域,其生物量最大;坡度越大生物量越小,陡坡不适宜竹林的生长;上坡位不利于竹林生长,而中、下坡位生物量没有显著差异;坡向对生物量的影响不明显,均适宜巴山木竹生长;在落叶阔叶和针阔混交林中,当林冠郁闭度>0.6时,竹林生长减弱。在这些立地因子中,影响巴山木竹生物量积累的主导因子是坡位和林冠郁闭度。     

圈养大熊猫全年食竹量观察

1982—1983年,我们在卧龙自然保护区就圈养大熊猫对竹子的食量作了为期一年的试验观察。材料与方法在饲养场选择4只健康的大熊猫,2♀、2♂,年龄3—23岁。冷箭竹(Bashania fangiana)和拐棍竹(Fargesia robusta)取自海拔2500米的英雄沟。给受试熊猫白天喂精料(黄豆、玉米和大米混合料500—700克,鸡蛋1个,奶粉50克),晚上喂竹子7.5—10公斤。投竹时称重,翌日晨收集剩余竹子称重。结果圈养大熊猫日食竹量为2.0—4.2公斤,平均3.1公斤(见表),与胡锦矗(1985)报道的野生大熊猫的日食竹量(12.5公斤)相比,差异极显著。老年熊猫食竹量较低,各月平均日食…     

秦岭大熊猫主食竹的分类学研究（I）

研究为秦岭大熊猫主食竹系列报道之一,主要报道产于陕西长青国家级自然保护区大熊猫主食竹。该保护区内共有野生禾本科竹亚科植物4属、5种,栽培逸为野生的1属、1种,其中巴山木竹（Bashania fargesii）和秦岭箭竹（Fargesia qinlingensis）为该区域大熊猫最主要的采食野生竹种,龙头竹（Fargesia dracocephala）次之,由栽培逸为野生的金竹（Phyllostachys sulpurea）为大熊猫喜爱的竹种。     

基于红外相机技术对佛坪国家级自然保护区 大熊猫季节性空间分布与活动模式的研究

2015年1月至2017年12月,在陕西佛坪国家级自然保护区海拔1 200~2 500 m的57条大熊猫(Ailuropodamelanoleuca)活动频繁的巡护样线上,布设130台红外相机。累计红外相机有效工作日100 685 d,共拍摄到大熊猫有效独立照片1 831张。将红外相机拍摄的有效照片和相机工作日依据不同竹种类型及保护站归类,对大熊猫季节性空间分布与活动模式进行研究。结果表明:(1)大熊猫春季活动最为频繁,在巴山木竹(Bashania fargesii)林和秦岭箭竹(Fargesia qinlingensis)林中相对多度分别是2.89和3.72;其次是冬季,在巴山木竹林和秦岭箭竹林中的相对多度分别是2.95和2.74。3月份是其活动高峰,巴山木竹林和秦岭箭竹林中的相对多度指数都是最高;11、12和1月份,大熊猫在巴山木竹林中相对多度指数高于秦岭箭竹林;2至10月份,大熊猫在秦岭箭竹林中的相对多度指数都要高于巴山木竹林。(2)大熊猫在佛坪保护区各个保护站均有分布,且存在季节性空间分布差异。三官庙和西河保护站全年的12个月都能够捕获到大熊猫的身影,是大熊猫分布相对多度最高的两个区域,大古坪、岳坝和龙潭子3个保护站海拔较低,大熊猫主要集中在冬春季节活动;凉风垭保护站海拔较高,主要分布的是秦岭箭竹林,大熊猫主要在夏季活动。(3)干扰活动主要包括采集、放牧、旅游、家犬活动和监测5种类型。干扰活动类型在各个保护站存在差异,且多为零星干扰,对大熊猫的活动和分布存在一定影响。本研究较为全面地调查了佛坪国家级自然保护区大熊猫季节性活动动态和区域性分布状况,调查结果可为后期的保护管理提供有效的参考依据。     

圈养大熊猫(Ailuropoda melanoleuca)觅食行为的初步观察

作者于2004年7～10月采用所有事件取样法（All-occurrence recording）和时间数据收集0-1取样法,对13只圈养大熊猫觅食行为观察,发现：圈养大熊猫食物中竹子占77％、其它占23％;幼体很少吃竹子,亚成体食竹量稍多于成体,亚成体觅食竹茎带高于成体,成体吃竹叶的量大于吃竹茎的量,偏好于吃竹叶;气温高于26℃后,大熊猫觅食频率有所下降,气温下降到22℃以下时,觅食频率开始上升;9：30～11：30和14：30～15：30为大熊猫觅食竹子的高峰期,与人为投食时间明显有关;圈养大熊猫日食竹时间占总时间的20％,其它活动时间占17％,休息时间占63％,明显短于野生大熊猫的觅食时间。以上观察结果对改进和完善圈养大熊猫的饲养管理具有重要的参考价值。     

Prevalence and lineages of Listeria monocytogenes in Chinese food products

AIMS: This study was undertaken to investigate the prevalence and lineages of Listeria monocytogenes in different kinds of food products in local Chinese markets. METHODS AND RESULTS: A total of 2686 food samples and 645 water samples were collected and L. monocytogenes was isolated from 2.28% (76 of 3331) of all samples. The prevalence of L. monocytogenes (14 of 290, 4.83%) in raw meat products was significantly higher than that in other raw food products (P < 0.05). Among 844 ready-to-eat (RTE) food samples, 21 samples were positive for L. monocytogenes. RTE packaged food products from two supermarkets had a prevalence ranging from 0.00% to 25.00%. The prevalence of L. monocytogenes in meat products of freshly slaughtered hogs was 0.95% (four of 420), significantly lower than that in raw meat products in the retail markets (P < 0.05). Ten isolates were recovered from 645 water samples, which were collected after hands washing by shopkeepers or waiters. A total of 38 isolates were randomly selected for lineage classification based on the nucleotide variation of actA gene. Eighty percentage of isolates from RTE food products belonged to Lineage II while only 20% belonged to Lineage I. CONCLUSIONS: Food products in Chinese markets are contaminated with L. monocytogenes. Raw meat products have the highest contamination rates among all the raw food samples. RTE food products are more likely to be contaminated with Lineage II strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The data presented here show the main contamination sources of L. monocytogenes in Chinese food products.     

Comparison of cold enrichment and U.S. Department of Agriculture methods for isolating Listeria monocytogenes from naturally contaminated foods. The Listeria Study Group.

We compared the cold enrichment (CE) and U.S. Department of Agriculture (USDA) methods for isolating Listeria monocytogenes by examining 402 food samples. The food samples were collected from refrigerators of listeriosis patients as part of a multistate active surveillance project to determine the role of foods in sporadic listeriosis in the United States. L. monocytogenes was isolated from 51 food samples (13%). The USDA method was significantly better (P less than 0.001) than the CE method. The isolation efficiencies of the USDA and CE methods were 96 and 59%, respectively. Quantitation of L. monocytogenes in the food samples revealed that many food samples containing less than 0.3 CFU/g were negative as determined by the CE method but positive as determined by the USDA method.     

Comparison of cold enrichment and U.S. Department of Agriculture methods for isolating Listeria monocytogenes from naturally contaminated foods. The Listeria Study Group.

We compared the cold enrichment (CE) and U.S. Department of Agriculture (USDA) methods for isolating Listeria monocytogenes by examining 402 food samples. The food samples were collected from refrigerators of listeriosis patients as part of a multistate active surveillance project to determine the role of foods in sporadic listeriosis in the United States. L. monocytogenes was isolated from 51 food samples (13%). The USDA method was significantly better (P less than 0.001) than the CE method. The isolation efficiencies of the USDA and CE methods were 96 and 59%, respectively. Quantitation of L. monocytogenes in the food samples revealed that many food samples containing less than 0.3 CFU/g were negative as determined by the CE method but positive as determined by the USDA method.     

Seasonal variations in food quality for pelagic and benthic invertebrates in Lake Erken – the role of fatty acids

1. Plankton net samples and sedimenting matter in traps from mesotrophic Lake Erken, Sweden, were analysed for carbon (C), nitrogen (N), phosphorus (P), total lipids and fatty acid (FA) content to determine what differences and seasonal changes might exist in the quality of food available to pelagic zooplankters and benthic invertebrates. 2. Matter collected in a plankton net was assumed to correspond to food available to pelagic grazers, while matter collected in sedimentation traps provided a measure of food available to benthic invertebrates. Furthermore, food quality was assumed to be related to polyunsaturated fatty acid (PUFA) content. 3. The results suggest that suspended particulate matter, collected with a plankton net, is a much higher-quality food resource than sedimenting matter. Our data also show that only during the spring and autumn do the benthic fauna have access to high-quality food, because of the dominance of diatoms during these periods. During summer, pelagic grazer production was probably limited by food quantity, whereas benthic invertebrate production was probably limited by food quality. 4. Plankton net samples showed consistently higher values than trap samples (% of dry weight, DW, or mg g^–1 DW) for nearly all variables analysed: C, N, P, saturated FA (SAFA), monounsaturated FA (MUFA), PUFA, ω3 FA and ω6 FA. If N and P were expressed per C, the differences decreased and both data sets indicated moderate to no N or P limitation. N/P also showed well-balanced ratios throughout most of the season, on average 10 and 7 (by weight), respectively. The largest differences between the two food resources occurred in the PUFA content, including the important FA of the ω3 type. The only FA with higher levels in the trap samples were some unidentified FA of relatively short chain lengths. Seasonal variation for most variables was also very large in both net and trap samples. 5. PUFA and ω3 FA showed good relationships with the P content of net samples, but not with that of trap samples. Eicosapentaenoic acid alone did not give a good relationship with P. Thus, P seems to be a good predictor of food quality in living phytoplankton but not in dead matter or detritus.     

Biases in Studying the Diet of the Bearded Vulture

Abstract: We compared methods of assessing the diet of the bearded vulture (Gypaetus barbatus) during the nestling period in the Pyrenees, northeast Spain. We determined diet from direct observations of food items delivered to the nest, recent prey remains present in the nest, remains collected in the nests after fledging, and remains collected in the ossuaries (bone-breaking sites). Data suggest that direct observation (food items delivered and recent prey remains present in the nest) is the only valid method of assessing the bearded vulture's diet accurately. Remains overestimated the presence of large mammals, such as cows (Bos taurus) and horses (Equus caballus), Suidae, and birds; delivered samples contained a higher proportion of small mammals, medium-sized mammals, micromammals, and reptiles. Ossuaries also differed from delivered samples because remains collected there overestimated large and medium-sized mammals. Concerning the skeletal parts, ossuaries, compared to all other methods, underestimated extremities and overestimated long bones, such as femur, humeri and tibiae, scapulae, vertebrae, and skulls. Remains samples, which overestimated scapulae, also differed from delivered and present samples. Our results suggest that bearded vultures favor extremities of prey (78% of the mammal remains, which make up 95% of the diet). The prevalence of small carcasses (almost 17%) suggests that vultures select small animals for food for the young. Because food quality may influence breeding success, future conservation projects based on the selective provision of food to breeding pairs should add to food stations meat remains and small carcasses consistent with our assessment of the birds’ dietary needs.     

Columnar cacti as sources of energy and protein for frugivorous bats in a semi‐arid ecosystem

Columnar cacti constitute the dominant elements in the vegetation structure of arid and semi‐arid New World ecosystems representing a plethora of food resources for vertebrate consumers. Previous stable isotope analysis in Central Mexico showed that columnar cacti are of low importance to build tissue for frugivorous bats. We used carbon stable isotope analysis of whole blood and breath samples collected from four species of frugivorous bats (Sturnira parvidens, Sturnira ludovici, Artibeus jamaicensis, and Artibeus intermedius) to reconstruct the importance of cactus plants in their diet. Breath samples were collected within 10 min (B₁₀) of bat capture and ~12 h after capture (B₇₂₀), representing the oxidation of recently ingested food and of body reserves, respectively. We expected that bats relied primarily on non‐cactus food to construct tissues and fuel oxidative metabolism. Non‐cactus food strongly predominated for tissue building, whereas oxidative metabolism was supported by a moderate preponderance of non‐cactus food for B₁₀ samples, and a moderate preponderance of cactus food or an equal contribution of both sources for B₇₂₀ samples. Artibeus and Surnira species appear to cover a narrow part of the diet with cactus food, confirming that the incorporation of nutrients derived from these plants is not generalized among vertebrate consumers.     

Fluorescently-labeled Oligonucleotide Probes Can Be Used To Identify Protistan Food Vacuole Contents

ABSTRACT. In situ hybridization using fluorescent oligonucleotide probes complementary to unique regions of 16S rRNA molecules provides a way of identifying the food vacuole contents of bactivorous protists. Laboratory experiments with Tetrahymena showed rRNAs in food vacuoles are degraded slowly enough to permit their use as hybridization targets for such probes. A probe specific for a hypervariable region of the small subunit rRNA of an unnamed proteobacterium abundant in a local lake was then synthesized. It was used to probe the food vacuoles of the ciliates present in fixed water samples collected from the same lake. The vacuoles of several filter-feeding ciliates bound the probe, indicating that such probes can be used to identify the food vacuole contents of ciliates collected from natural samples.     

重庆部分地区的种质资源调查荞麦篇

"第三次全国农作物种质资源调查与收集"重庆项目组,于2015年10月至11月初在重庆市巫山县、奉节县和石柱县3个县开展了农业生物资源的系统调查,通过深入村社和农户,调查了解作物种类与品种多样性情况,收集和挖掘古老、特有和稀少种质资源。本次调查共收集到农作物地方品种和野生近缘植物种质资源341份,其中粮油作物136份、蔬菜86份、果树57份、茶树5份、烟草22份、牧草30份、麻类5份。本文重点介绍在粮油作物中的荞麦种质资源调查和资源收集情况,在收集到的19份荞麦资源中,既有珍稀、古老的地方品种,也包括特有野生资源。荞麦承载了彝族等少数民族的文化内涵,随着现代农业的发展,荞麦的古老、珍稀和特有种质资源正在流失,建议相关部门因地制宜,在发展现代农业生产的同时,采取必要的经济措施,对古老、珍稀和特有的荞麦种质资源,进行农户或原生境保护,为进一步开发利用提供种质资源基础。     

Occurrence of fumonisins (B<Subscript>1</Subscript>, B<Subscript>2</Subscript>, B<Subscript>3</Subscript>) in maize-based food and feed samples from Indonesia

A survey to evaluate the contamination level of total fumonisins in maize-based foodstuffs, maize and feed from Indonesia is described. The analyses were carried out by enzyme-linked immunosorbent assay (ELISA). Samples were collected from local retail stores around Yogyakarta, Indonesia between February and May 2001. The 101 samples were classified into six categories, i.e. industrially-produced food (n=24), products of small food manufacturers (n=17), maize flour (n=4), maize for food (n=9), maize for feed (n17), and formulated feed (n30). Control of the method showed that the detection limit was 8.7 μg/kg and repeatability is shown by relative standard deviation (RSD) of analyses of contaminated maize (n=5) of 10 %. Results of analyses indicate that 80 samples analysed were contaminated over a large range from 10.0-3307 pg/kg, and the concentration of fumonisins depended on the type of sample. Of four samples of maize flour, none were contaminated (below detection limit). Of 24 samples of industrially produced food, 14 were contaminated in the range 22.8 - 105 μg/kg and 18 of 19 food samples from small manufacturers were contaminated ranging from 12.9 to 234 μg/kg. The highest contamination was observed in maize samples: six of ten samples of maize for food were contaminated between 68.0 - 2471 μg/kg and 16 of 17 samples for feed contained fumonisins over a large range from 17.6 to 3306 μg/kg.     

Food resource availability for American black ducks wintering in southern New Jersey

Midwinter waterfowl survey data indicates a long-term decline in the number of wintering American black ducks (Anas rubripes), potentially due to habitat limitations. In order for future estimates of carrying capacity to be determined, it is critical that regional food availability is estimated. We collected pairs of habitat core samples (n = 510) from 5 habitat types in southern New Jersey, USA, during October, January, and April 2006–2008 to estimate resource availability and variability. We collected upper gastrointestinal tracts from hunter-killed birds (n = 45) and late season collections (n = 19) to identify food items and limited our estimates of resource availability to only winter food items; thereby reducing the availability of seed foods found in our core samples by 38% and animal foods by 96%. We did not detect differences in years or sampling period, but did between habitat types. Mudflat habitat had the greatest availability of invertebrate and vertebrate food items and appeared to supply the bulk of energy to black ducks wintering in southern New Jersey. We suggest conservation efforts to be focused on restoring or enhancing mudflat habitat as an integral component of an ecologically functioning salt marsh to increase food availability. © 2011 The Wildlife Society.