兽类的死亡率

本文共收集了３３种兽类的年均死亡率数据。求得陆生兽类的死亡率和体重的回归模型为： Ｄｔ＝０．６９５－０．０９７３ｌｎ Ｗｔ（ｒ２＝０．８６５,ｐ＜０．００１） Ｄｈ＝０．７３２－０．１００ｌｎ Ｗｈ（ｒ２＝０．８９１,ｐ＜０．００１） Ｄｃ＝０．６１９－０．０９０８ｌｎ Ｗｃ（ｒ２＝０．８６９,ｐ＜０．００１）这里,Ｄｔ、Ｄｈ和 Ｄｃ分别为陆生兽类、食植兽类和食肉兽类的年均死亡率;Ｗｔ、Ｗｈ和 Ｗｃ则分别是它们的体重（公斤）。研究发现：陆生兽类的体重决定了年均死亡率８６％以上的变异：食肉兽类比同样体重的食植兽类的年均死亡率小;飞行兽类比同样体重的陆生兽类的年均死亡率小。兽类死亡率的这一变异规律被认为和能量限制有关。     

孵化期间鹌鹑蛋各成分的水分变化及胚胎生长

孵化期间鹌鹑蛋中黄和蛋白的含水量变化呈互补性，即蛋黄含水多时，蛋白含水量少，蛋黄含水少时，蛋白含水量多，但人孵前蛋黄含水同出壳时剩余蛋黄含水量无显著差异，孵化期间胚胎含水是逐渐减少的，第９日龄前胚胎生长缓慢，第９日龄后胚胎呈直线生长，湿重的生长模型为Ｙ＝０．０００４Ｘ＾３．５９（ｒ＝０．９９，Ｐ〈０．０１），干重的生长模型为Ｙ＝０．００００２Ｘ＾４．１０８４（ｒ＝０．９９，Ｐ〈０．０１）。     

承德市油松针叶硫及重金属含量动态及其与大气SO2之间的关系

本文分析了承德市油松（ＰｉｎｕｓｔａｂｕｔａｅｆｏｒｍｉｓＣａｒｒ．）针叶硫和重金属含量变化及其与大气ＳＯ＿２浓度之间的相关性,探讨了油松针叶对大气ＳＯ＿２的生物监测作用,结果认为：植物Ｓ含量生长末期＞休眠期＞生长初期＞生长旺盛期（ｐ＜０．００１）;重金属中Ｐｂ表现为类似的规律,Ｓ和Ｐｂ含量分别从０．７５ｍｇ·ｇ￣（－１）和０．７μｇ·ｇ￣（－１）上升到１．５８ｍｇ·ｇ￣（－１）和２．０μｇ·ｇ￣（－１）。Ｎｉ变化不明显;Ｚｎ、Ｃｕ和Ｆｅ呈下降趋势,但Ｚｎ在休眠期略有回升。Ｍｎ在休眠期最高,但生长期也很高,其余季节相对较低。这种变化特点与大气中ＳＯ＿２和总悬浮颗植物（ＴＳＰ）的变化趋势基本一致;油松针叶Ｓ含量与大气ＳＯ＿２浓度之间具有很显著的相关性,其中火车站监测点生长季节相关公式Ｙ＝－０．０２６３＋０．０９６５Ｘ（ｒ＝０．８９１１,ｐ＜０．００１）;城区Ｙ＝０．０１２６＋０．０６１８Ｘ（ｒ＝０．７８４１,ｐ＜０．０１）。利用后者可对整个承德市区的大气ＳＯ＿２污染状况进行生物监测。     

白水江自然保护区糙花箭竹天然林生物量与生产力的初步研究

本文根据样方上测定糙花箭竹的地径,茎高,密度,茎重,枝条重,叶重和鞭系重资料,研究竹林生物量和生产力,并建立回归数学模型为“茎重ＷＳ＝１６０．９４２＋０．２７７（Ｄ＾２ＮＨ） ｐ＜０．００１,枝条重ＷＢ＝７６．００８＋０．０３９（Ｄ＾２ＮＨ） ｐ＜０．００１,叶重ＷＬ＝８０．６４３＋０．０５１（Ｄ＾２ＮＨ） ｐ＜０．００１,鞭系重ＷＲ＝２８５．５５４＋０．０７４（Ｄ＾２ＮＨ） ｐ＜０．００１     

北京山区辽东栎林土壤释放CO_2的模拟实验研究

模拟北京山区辽东栎林群落,对该类型土壤释放ＣＯ２过程进行了连续３ａ的实验研究,结果表明：辽东栎林土壤呼吸强度平均为５．９２±１．３２μｍｏｌＣＯ２ｍ－２ｓ－１,在不同月份中,以８月份最高,１０月最低,依次为８月＞７月＞６月＞９月＞１０月（Ｐ＜０．０５）;１３：００为土壤日呼吸的最高峰。温度为影响土壤呼吸的主要因子,二者存在极显著相关关系（ｒ＝０．５６６８,ｐ＜０．００１,ｎ＝９４）。据３ａ观测的土壤呼吸日平均值计算得出,模拟辽东栎林土壤释放ＣＯ２的通量估计范围为１７１．５～２７５．１ｋｇＣＯ２ｈｍ－２ｄ－１,平均为２２３．３ｋｇＣＯ２ｈｍ－２ｄ－１。     

桐粮间作林带的配置方式与农作物产量关系的研究

以桐粮间作为例,研究了林带的不同配置结构、林带冠覆盖率及小麦产量之间的关系。结果表明,林带距（Ｘｄ）、小麦相对产量（Ｙ）及间作年（Ａ）之间的关系为：Ｙ＝９０．３２９０－１．９９８２Ａ＋１．１９２４Ｘｄ－０．３３４９Ａ＾２＋０．２９１０ＡＸｄ－０．００３２ＡＸｄ＾２;林带冠覆盖率（Ｘｃ）与小麦相对产量（Ｙ）之间的关系为：Ｙ＝－０．０４６Ｘｃ＾２＋１．１５３９Ｘｃ＋９８．１７３（Ｘｃ≤２８％）,Ｙ＝ｅ     

胎羊缺氧模型的血流动力学改变

目的和方法：健康妊娠绵羊７只,体重２０～３０ｋｇ。于妊娠１１６～１２５ｄ行胎儿外科手术。经胎儿股动脉插管引出腹主动脉血压,放置脐动脉电磁流量计探头记录血流信号。术后恢复１ｈ。从胎儿动脉导管注入明胶微球悬浮液（≈５０μｍ）造成胎盘微血管阻塞,每隔１５～２０ｍｉｎ注射一次,构成胎儿缺氧动物模型。采集胎儿动脉血样。分析ｐＨ、ＰａＣＯ２和ＰａＯ２值。分析脐动脉输入阻抗。结果：１、外周阻力Ｒ与血管阻塞程度呈指数关系（ｒ＝０．９７,Ｐ＜０．００１）,但脐动脉特征阻抗基本不变;２、胎儿动脉血氧分压随血管阻塞程度增加而下降（ｒ＝０．８７,Ｐ＜０．００１）;ｐＨ值随血管阻塞程度的增加而减小（ｒ＝０．８５,Ｐ＜０．０１）;二氧化碳分压随血管阻塞程度增加而上升（ｒ＝０．７１,Ｐ＜０．０５）;３、脐动脉血流量与外周阻力呈幂函数关系（ｒ＝０．９９,Ｐ＜０．００１）。结论：本工作为研究胎儿窘迫的病理生理机制提供了成功的动物模型     

黑鲷的胃排空率

在实验室内,18℃条件下测量了体重在 2 0～40g的黑鲷的胃排空率,并用 3种数学模型拟合了黑鲷的排空率.结果表明,3种模型都能很好地拟合实验数据,但通过统计学分析发现不论是用湿重还是用干重表示胃含物,线性模型都拟合得最好.用湿重表示时模型为Y=1.14-0.06t(r²=0 82,p<0.001);而用干重表示时模型为Y=1.36-0.07t(r²=0.62,p<0.001).实验还得出体重20～40g的黑鲷在 18℃的胃排空率为每小时排出摄入食物量的 6%～7%.     

败血症大鼠肝细胞核Ca^2＋转运功能的改变

本实验观察败血症时肝细胞核钙转运的变化。早期败血症（结扎盲肠及穿刺后,９ｈ）大鼠肝细胞和肝细胞核钙含量分别增加２０％和３６％（Ｐ〈０．０５）。败血症大鼠肝细胞核Ｃａ＾２＋－ＡＴＰａｓｅ活性增加９４％（Ｐ〈０．０１）,核＾４５Ｃａ＾２＋转运显著增强（增加３２％,Ｐ〈０．０１）。核＾４５Ｃａ＾２＋转运与Ｃａ＾２＋－ＡＴＰａｓｅ活性呈明显正相关（ｒ＝０．９１４,Ｐ〈０．０１）。加入钙调素显著刺激而加入钙     

三突花蛛对茶小绿叶蝉的捕食作用及其模拟模型的研究

在室内条件下,测定结果表明三突花株亚成蛛对茶小绿叶蝉若虫及成虫的日捕食量分别为１８．３头／ｄ,１７．３头／ｄ,对成虫的功能反应曲线可用ＨＯｌｌｎｇ圆盘方程模拟：Ｎａ＝１．０５５８６Ｎｔ／（１＋０．０１３６５／Ｎｔ）自身密度反应用Ｈａｓｓｅｌ－Ｖａｒｌｅｙ模型拟合,Ｅ＝０．５１７Ｐ＾－０．６５６７,经Ｘ＾２检验,以上各方程理论值与实际值误差不显著（〈Ｐ０．１０）。温度（Ｔ）对功能反应的影响可用以下方     

Rates of gastric evacuation in piscivorous brown trout, Salmo trutta

SUMMARY. 1. The dry weight of food remaining in the stomachs of piscivorous trout decreased exponentially with time. Gastric evacuation rates increased exponentially with increasing temperature but were unaffected by predator size, meal size or type of fish prey.
2. Mathematical models were developed to estimate both the rate and time for the gastric evacuation of different meal sizes (expressed as dry weight), and were applicable to piscivorous trout of different sizes (length range 10–32 cm) feeding on trout fry or sticklebacks at different temperatures (range 5–18°C).
3. The wet weight of food in the stomachs also decreased exponentially with time, but evacuation rates both increased with temperature and decreased with increasing meal size; the latter relationship occurred because relative rates of water loss from a meal also decreased with increasing meal size. Use of wet or dry weights can therefore lead to different conclusions about the effect of meal size on evacuation rates.
4. When piscivorous trout were fed three consecutive meals of varying size, the models predicted the total dry weight of food left in the stomach, but not the weight remaining for each individual meal. Interactions between meals led to an increase in evacuation rates for meals consumed early in the series and a decrease in evacuation rates for later meals.
5. Evacuation rates for piscivorous trout were compared with those for trout feeding on invertebrates in an earlier study, and were close to those for caddis larvae as prey, higher than those for mealworms and lower than those for a variety of invertebrate prey. Although a great deal is now known about the daily food intake and growth rates of trout feeding on invertebrates, there is little comparable information for piscivorous trout.     

Gastric evacuation rates for two foods in the black rockfish, Sebastes melanops Girard

The rates of gastric evacuation of two food types, squid and fish, were measured in the laboratory for adult black rockfish, Sebastes melanops , held nominally at 11°C. Linear, logarithmic and square root regression models were applied to analyse the data expressed as both wet and dry weight proportions of the original meal. The linear model provided the best fit for the wet weight relationship of squid. The dry weight of squid and both the wet and dry weight of fish were best described by a logarithmic model, or by a square root model when the regressions were' forced' through the original meal size. The instantaneous evacuation rates (≃ 6% h⁻¹) and times to complete evacuation (≃ 76 h) were similar for all relations except those involving the wet weight of squid. The addition of the meal size as an independent variable improved the models in most cases whereas the addition of the weight of fish used in the experiments did not improve the model in any instance.     

Gastric evacuation of three food types in the black and yellow rockfish Sebastes chrysomelas (Jordan and Gilbert)

The evacuation patterns of shrimp, crab and fish from the stomachs of black and yellow rockfish, Sebastes chrysomelas , were examined by feeding meals of known size and measuring the amount remaining after various post-prandial intervals. Linear, square-root, exponential, power exponential, logistic and Gompertz models (the latter two with unrestricted lower asymptotes, or with lower asymptotes restricted to 0% food remaining) were fitted to the wet weight, dry weight and volume of food remaining in the stomach as a function of post-prandial time. Evacuation patterns ranged from steeply concave (fish wet weight, dry weight, volume, shrimp dry weight), to linear (shrimp wet weight, crab dry weight), to highly convex with lag phases of up to 30 h (crab wet weight, crab and shrimp volume). Friability, the ease with which a food item is fragmented in the stomach, may be an important factor in determining evacuation patterns. The evacuation of a crab meal by tagged, free-ranging S. chrysomelas in the field was not significantly different from that of S. chrysomelas held in the laboratory.     

Gastric evacuation in horse mackerel. I. The effects of meal size, temperature and predator weight

Gastric evacuation experiments were performed on horse mackerel Trachurus trachurus. A nearly full matrix experimental design with respect to the variables predator weight (<10–400 g) meal size (up to 7·8% body weight) and temperature (10–20°) was covered with 0-group smelt Osmerus eperlanus as prey. A general evacuation model without meal size as a variable was fitted to the data on wet weights as well as on dry weights by means of non-linear regression technique. Two methods of data transformation, relative data and square root transformation, were applied to improve variance homogeneity. The most reliable model fit was achieved on dry weight data applying the square root transformation technique: where S_t=stomach content (g wet weight) at time t after ingestion, S₀=the initial meal size, W =predator (g wet weight), and T =temperature. The estimated coefficient of the exponential temperature function, δ=00·032, corresponds to a Q ₁₀ value of 1·4 which is outstandingly low in comparison with results on other species. However additional experiments to determine maximum daily food rations indicated that appetite in contrast to gastric evacuation is strongly temperature dependent.     

Patterns of gastric evacuation, digesta characteristics and pH changes along the gastrointestinal tract of gilthead sea bream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.)

A comparative study of gastric evacuation rates (GERs) and digesta content, moisture and pH values along the gastrointestinal tract was performed between gilthead sea bream and European sea bass. In order to distinguish species-specific differences from diet-elicited effects, all parameters were determined under either a fishmeal diet or a carob seed germ meal diet that contained high levels of total and soluble non-starch polysaccharides. GERs were significantly different between species and they were not affected by diet. Similarly, species-specific patterns were revealed in the distribution of digesta and water content along the gastrointestinal tract. In sea bream, stomach digesta and water content decreased with time, whereas in sea bass stomach retained the highest digesta and water content throughout the sampling period. The anterior and distal intestine exhibited the lowest accommodating capacities of digesta and water in either species. Overall, sea bream performed stomach digestion at lower hydration levels and higher pH compared with sea bass. Diet affected stomach moisture in both species and pH of stomach digesta in sea bass and of all intestinal sections in sea bream. The results obtained indicated that water and inorganic ion exchanges through the gut may differentiate between the species and warrant further investigation.     

In situ estimates of gut evacuation and its dependence on temperature in five cyprinids

Gut evacuation and its dependence on the temperature in bream Abramis brama , silver bream Blicca bjoerkna , roach Rutilus rutilus , gibel Carassius aurtaus gibelio and carp Cyprinus carpio , held in mesh cages in Lake Balaton, was best fitted by an exponential model in 18 of 36 trials, while in 14 and four trials, a linear and a square-root model, respectively, gave a better fit. Adjusted r ² values, however, often did not differ markedly between the three models. The shape parameter, B , was 0.36 for carp and ranged from 0.81 to 1.24 for the other four cyprinids, according to the general evacuation model expanded with the temperature variable, and fitted to whole data sets. Relationships between the food evacuation rates obtained from the exponential models and the temperature were described by exponential functions for bream, silver bream, roach and gibel.     

钻井噪声与振动对草鱼摄食和生长转换效率的影响——Eggers胃含物法在现场模拟研究中的应

研究首次将Eggers胃含物法应用于钻井噪声与振动污染对草鱼影响特征的现场模拟实验中.结果主要阐明(1)钻井噪声与振动的污染特征,定量描述了污染源距离与钻井噪声或振动等效声级之间的关系;(2)草鱼排空率实验中,消化道内含物随时间的变化趋势为St=4.997e-0.3202t,瞬时排空率为Rt=o.3202 gW·W/(kg·h).(3)钻井噪声与振动污染对草鱼最大摄食量、生长和生长转换效率均有显著影响,但影响程度却有所差别.(4)草鱼摄食、生长均随钻井噪声与振动强度增大呈减小趋势;其中摄食量较为敏感,但对生长的影响程度却远大于摄食.     

Gastric evacuation in plaice, Pleuronectes platessa L.: effects of temperature and fish size

Using a volume dependent model of gastric evacuation, the effects of temperature and fish size were examined. Rates of gastric evacuation were unaffected by fish size but increased with increasing temperature. The relationship between maximum stomach volume and fish weight was found to be a linear one. From information of gastric evacuation rates and stomach volume, the amount of food evacuated from the stomach per day was calculated for different size classes of fish. Daily food evacuation increased in proportion to body weight to the power 0·68. Assuming these methods give a crude estimate of daily food intake, the results are discussed in relation to published work on food intake in fishes.     

Feeding ecology and daily food consumption of common sole, Solea vulgaris Quensel, juveniles on the French Atlantic coast

This study describes feeding rhythms in juvenile sole (0- and I-groups) and differences in choice of prey according to age and feeding time. In the same biotype, 0-group fish select amphipods or young opisthobranchs, whereas I-group fish eat chiefly polychaetes such as Pectinaria koreni . The daily food consumption for juvenile soles in the field (T = 19.8°C) is estimated at 7% body dry weight in 0-group and probably less in I-group. When compared with estimates from previous methods or models, these rations are intermediate between estimates from Kuipers' method, with a gastric evacuation rate ( R ) per hour representing three times the amount of food in the stomach, and those from Elliott & Persson's model with R value around 1.46.