社鼠消化道长度和重量的季节变化

社鼠消化道长度和重量的季节变化ＳＥＡＳＯＮＡＬＶＡＲＩＡＴＩＯＮＳＩＮＬＥＮＧＴＨＡＮＤＷＥＩＧＨＴＯＦＤＩＧＥＳＴＩＶＥＴＲＡＣＴＩＮＲＡＴＴＵＳＮＩＶＩＶＥＮＴＥＲＣＯＮＦＵＣＩＡＮＵＳ关键词社鼠消化道形态季节动态ＫｅｙｗｏｒｄｓＲａｔｕｓｎｉｖ...     

社鼠和褐家鼠消化道长度和重量的季节变化

测定了浙江金华的社鼠和褐家鼠消化道长度和重量的季节变化。野生社鼠消化道各器官无论长度不审重量都有明显季差异,在寒冷的冬季具有相对较大的小肠、大肠、盲肠、雄性社鼠的消化道长度在秋季由于食物条件的改善而明显下降,但雌性社鼠由于在秋季仍有繁殖负担,其消化道长度下降不明显,而家栖的褐家鼠只有总消化道、小肠和大肠的长度有季节差异,冬、春季高于夏、秋季。消化道形态季节变化与温度、食物条件和繁殖有关。     

实验条件下小型啮齿动物体重与体长模型的数值拟合

曲线拟合是生态学模型的重要研究内容之一。国内外对实验条件下的小型啮齿动物的体重与体长的研究可分为 3类 :附原始数据并给出体重与体长的 Lagler模型 ;附原始数据和体重与体长图形 ;给出体重与体长的图形或 L agler模型 ,但缺少比较系统的分析和总结。虽然查阅了国外近几十年的有关论文 ,但有些文献仅能看到摘要或题目 ,因此 ,本文仅对国内附原始数据的论文作进一步探讨。1　材料来源与方法　　用于分析实验条件下啮齿类的体重与体长增长动态的原始数据来自板齿鼠 ( Bandicota indica) [1]、草原兔尾鼠 ( L agurus lagurus) [2 ]、黄…     

突变体——侏儒小鼠(dw~t)与津白3(TA3)不同日龄骨骼、体重及体长的比较

侏儒小鼠与津白3体重的比值为1:2.5。它们的骨骼、休重、休长及尾长的测量均具非常显著或显著意义。经均衡性检验,不同日龄、不同性别间TA3/dw~t小鼠的不同骨骼、体重、体长及尾长的比值变化是均匀一致的。证明侏儒小鼠骨骼、体重、体长及尾长均系均匀缩小,是身体各部分匀称的侏儒小鼠。     

SEASONAL VARIATIONS IN TOTAL NITROGEN,CARBON AND AMINO ACIDS IN MACROCYSTIS INTEGRIFOLIA AND NEREOCYSTIS LUETKEANA (PHAEOPHYTA)1

Seasonal variations in tissue nitrogen, carbon, amino acids and ammonium were determined for the brown algae Macrocystis integrifolia Bory and Nereocystis luetkeana (Mertens) Pastels and Ruprecht, For M. integrifolia, the proportions of tissue nitrogen and carbon in blades, bulbs and stipes were also determined. The composition of the two algae in terms of the above constituents was similar. In addition, ammonium, nitrogen and protein-bound amino acids showed distinct seasonal trends with high values during the winter and low levels during the summer. The range for nitrogen was 0.8–3.0% and for proteins 7.6–11.7% of dry weight. In contrast, carbon content and C/N ratio showed the reverse trend with higher values during the summer and lower values during the winter. The range for carbon was 19–31% of dry weight, and the C/N ratio showed a range of 9–37. The free amino acids did not show any specific seasonably. Tissue nitrogen and carbon showed higher values in the blades than in the bulbs and stipes.     

DIET OF WEANED PUPS AND SEASONAL VARIATIONS IN BODY CONDITION OF JUVENILE BARENTS SEA HARP SEALS PHOCA GROENLANDICA

Data on blubber depth, body condition, and diet were collected from young of year and juvenile harp seals ( Phoca groenlandica ) in the Barents Sea in the periods February-April and June-October 1990–1997. Harp seal pups feed independently shortly after weaning. In the southern parts of the Barents Sea the diet of harp seal pups consisted mainly of euphausiids ("krill") Thysanoessa sp. and amphipods of the genus Parathemisto . The change in body condition of harp seal pups between weaning (mid-March) and June indicated that considerable amounts of blubber energy, deposited during suckling, were mobilized. This suggests that the early food intake of weaned pups was insufficient to meet the energy requirements. The pattern of low spring and earlysummer body condition, followed by a subsequent rapid improvement in condition during late summer and autumn appeared to occur not only among pups-of-the-year, but also in one- and two-year old harp seals.     

VARIATIONS IN GROWTH,EROSION, PRODUCTIVITY,AND MORPHOLOGY OF ECKLONIA RADIATA (ALARIACEAE; LAMINARIALES) ALONG A FJORD IN SOUTHERN NEW ZEALAND1

Spatial and temporal patterns of growth, erosion, productivity, and morphology of the dominant habitat‐forming kelp Ecklonia radiata (C. Agardh) J. Agardh were studied bimonthly over 1.5 years in a southern New Zealand fjord characterized by strong gradients in light and wave exposure. Spatial differences in growth were observed with rates at two outer coast, high‐light, wave‐exposed sites reaching 0.42 and 0.45 cm · d^?1, respectively, compared to 0.27 cm · d^?1 at an inner, more homogeneous site. Sporophyte productivity was similar among sites, although population productivity was greater at the outer sites due to population density being 5‐fold greater than at the inner site. It was expected that the inner site would have no pronounced seasonal pattern in growth and productivity due to its homogeneity; however, all three sites displayed maximum rates in late winter/spring and minimal in autumn. Growth rates were 2‐fold greater during the first growth period than the following year. This discrepancy was not correlated to inorganic nitrogen (N) levels, which remained low year‐round (<4 μM), and is likely a result of an interaction between light and temperature, and the photosynthetic capability of E. radiata. Variable pigment content indicated photoacclimation at the inner site. Morphological differences were observed between sites, with E. radiata from the inner site having longer, wider, thinner blades and longer stipes. While E. radiata displayed spatial differences in growth, erosion, productivity, and morphology, populations displayed no temporal differences. These results highlight the need for greater understanding of the mechanisms influencing kelp growth and productivity in a unique marine environment.     

高寒地区高原鼢鼠消化道形态的季节变化

对青海高原地区的高原鼢鼠在自然环境中消化道各器官的长度及重量的季节变化进行了测定,结果显示总消化道保持相对的稳定性,长度、鲜重及于重均相对稳定,而含内容物器官重季节性变化明显。胃的变化相对较稳定,但长度季节性变化显,草枯黄期值最高,草生长盛期最低;小肠的鲜重在草返青期明显低于草生长盛期和草枯黄期;盲肠的变化最大,其长度和含内容物器官重草返青期明显高于其它季节。大肠的干重于枯黄期显增加。各器官的     

蒙古旱獭体重体长变化及其年龄划分的研究

本文报告了645只蒙古旱獭体重体长变化与年龄的关系。结果表明:体重体长随年龄增长而递增,但体重和体长的增长速度和幅度不同。体重增长速度较快,幅度较大;体长增长速度较慢,幅度较小。经相关分析证明:体重体长与年龄呈正相关,相关系数和回归方程为: Y_w=1377.16x~(O.7729),R_w=0.9970; Y_L=33.95x~(0.2529),R_L=0.9947。 并根据相邻两个年龄组间体重均数有显著性差异(P<0.01),频数分布重叠不明显;组内变异具有一致性等特征,参考各年龄组蒙古早獭体重标准值(Mean ±Sx),划分了各年龄组早獭的体重范围。     

达乌尔黄鼠产热的季节性变化

达乌尔黄鼠（Ｃｉｔｅｌｌｕｓｄａｕｒｉｃｕｓ）的产热表现出明显的季节性变化。在非冬眠期,静止代谢率（ＲＭＲ）和非颤抖性产热（ＮＳＴ）于春季最高,秋季次之,夏季最低。冬眠期,ＲＭＲ降到极低水平,只为春季的３．０％。肝脏的线粒体蛋白含量、线粒体呼吸和细胞色素Ｃ氧化酶活力在秋季显著高于其它各季。褐色脂肪组织（ＢＡＴ）的重量、线粒体蛋白含量、细胞色素Ｃ氧化酶活力和α－磷酸甘油氧化酶活力,在夏季处于一年中的最低水平,到了冬季这些指标达到一年中的最高水平。在非冬眠季节ＢＡＴ产热能力升高时,ＮＳＴ能力也相应升高,这表明ＢＡＴ产热能力的增强是ＮＳＴ能力提高的部分机制。达乌尔黄鼠血清Ｔ＿４含量在年周期中没有明显改变,冬眠时血清Ｔ＿３含量显著高于其它各季。     

武汉东湖透明溞和隆线溞一亚种体长-体重回归方程式

透明溞(Daphnia hyalina)和隆线溞一亚种(Daphnia carinata ssp.)是东湖优势枝角类。       

鱼类的重量-身体维数关系的研究

在运用一元数学公式:W=alb(或W=aLb)来描述鱼类的重量与身体维数关系时存在许多缺陷。作者从确立一条模式鱼的边界曲线方程出发,应用求旋转体体积的方法建立了鱼类重量与长度、体高的多元数学公式: W=alb1Hb2(或W=aLb1Hb2),并推演出鱼类重量与长度、体高、体周长之间的另外两种关系式: W=alb1Sb3(或W=aLb1Sb3) 和W=alb1Hb2Sb3(或W=aLb1Hb2Sb3)。上述几类多元数学公式在用来拟合白鲢、翘嘴红鲌和长春鳊种群及它们的不同生长阶段的观测数据时,都比一元数学公式更接近于实际情况,由多元数学公式进行预报的精度也比一元数学公式高。多元数学公式之所以优于一元数学公式是因为多元数学公式能够较全面地反映不同维数对鱼体重量的综合影响。对于不同体形的鱼类,不同维数对重量影响的程度是不同的,因此在应用时应有所选择。从多元数学公式的组成及应用情况看,真正有使用价值的是考虑了体周长的二元数学公式。由于体高易于测量,为此考虑了体高的二元数学公式更具有实用价值。作者建议,在鱼类生长的理论与应用研究中,可采用: W=alb1Hb2(或W=aLb1Hb2) 和W=alb1Sb3(或W=aLb1Sb3) 来描述鱼类的重量与身体维数之间的关系。       

SEASONAL VARIATIONS IN RESERVE AND STRUCTURAL COMPONENTS OF PINUS RESINOSA CONES

Changes in reserve materials, lignin, hemicellulose, and cellulose of 1st-year conelets and 2nd-year cones of red pine (Pinus resinosa Ait.) were studied by chemical extraction of the respective fractions. During the first 11 months after emergence of conelets, reserve materials, primarily carbohydrates, constituted approximately half of the dry weight of cones. Cellulose and hemicellulose contents were low but cells were highly lignified. During summer of the 2nd year of cone development, marked compositional changes occurred. A rapid surge of cone growth, possibly triggered by resumption of pollen-tube growth and fertilization, occurred from mid-June to early August and was accompanied by transformation of reserve materials into cellulose and, to a lesser extent, into hemicellulose and lignin. During this transformation, the thickening and lignification of cells responsible for the opening of cone scales probably occurred. The developing seeds also mobilized readily available cone reserves during this time.     

禁食对小鼠体重、SOD和丙二醛含量的影响

给小鼠禁食4天后观察体重、肝SOD和心肌丙二醛的影响。结果表明,禁食期间小鼠的体重明显减轻,复食后体重很快恢复;肝脏SOD的活性明显提高,心肌丙二醛的含量显著下降。提示短期禁食具有抗衰老的效应,可提高机体的生存能力。     

SEASONAL GROWTH AND NUTRIENT ECO-PHYSIOLOGY OF ECKLONIA RADIATA FROM DOUBTFUL SOUND, FIORDLAND, NEW ZEALAND

The kelp, Ecklonia radiata , dominates the sublittoral zone within the Doubtful Sound complex. Doubtful Sound is one of a series of fourteen fiords indenting the southwestern coast of the South Island, New Zealand. A feature of these fiords is the freshwater layer that resides atop the salt water, creating a unique marine environment. Mature sporophytes were collected from three sites (two outer sites towards the coastline and one site within the fiord) over a fourteen-month period (October 1998 to December 1999). Growth rates, measured using the hole punch technique, were greatest in spring at all three sites. The nutrient eco-physiology of mature E. radiata was investigated by measuring inorganic nitrogen (NO⁻³ and NH⁺⁴) uptake rates at eight concentrations (2–64 μM). Soluble tissue nitrogen (NO⁻³ and NH⁺⁴) and tissue carbon:nitrogen (C:N) ratios were also determined. At all sites, E. radiata showed higher uptake rates for ammonium than for nitrate. In winter, soluble tissue nitrogen was lower at the two outer sites compared to the inner site, while in summer, levels at all sites were similar but had decreased from the winter values. C:N ratios greater than 20 were observed at all sites, increasing in summer to a peak in autumn, suggesting E. radiata may be nitrogen limited, particularly in late summer. Environmental parameters (photon flux density, water temperature, rainfall and wind) were measured, as was sea water velocity around the primary blade of E. radiata , and multivariate correlations used to determine which (if any) environmental parameter exerted greatest influence on eco-physiological parameters accessed.     

上海淀山湖浮游桡足类群落组成与季节变动研究

本文报道了1984年2月至1985年2月上海淀山湖浮游桡足类的群落及优势种数量季节变动的调查结果．在淀山湖共获得11种浮游桡足类,隶属2目5科10属;根据各种类出现的月份,可以把这儿种桡足类划分成4种类型,终年出现型、夏秋季型、冬春季型和畏严冬型;在湖泊敞水区的浮游桡足类,年数量变动曲线有春季、夏季以及秋季三次高峰,秋季高峰比春季、夏季高峰更突出,持续时间约两个月;中华窄腹剑水蚤、汤匙华哲水蚤、广布中剑水蚤和近邻剑水蚤这4个优势种制约了桡足类群落总数量的季节消长。浮游桡足类生物量的季节变动有4次高峰,春季及秋季高峰出现时间迟于总数量高峰,其原因是数量高峰期桡足类群落中含有约80—90％的幼体,幼体成长之后方能达到生物量高峰期。本文还就影响浮游桡足类群落数量、生物量的生态因子作了初步的讨论。