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1.
牦牛种群的能量流动态及其在系统能量流中的地位和作用   总被引:5,自引:0,他引:5  
蒋志刚  夏武平 《生态学报》1987,7(3):266-275
继作者(1984)初步探讨了高寒草甸生态系统中牦牛种群的能流动态以后,本文深入探讨了牦牛种群的能流动态及其在生态系统能流过程中的地位和作用。从测定牦牛的日摄入能、消化能着手,估算了由于瘤胃微生物发酵而产生的甲烷能量损失和代谢能,研究了高寒草甸生态系统中,每公顷面积上通过绿色植被和牦牛种群的能量流密度之物候期动态。比较了次级营养层上3种优势草食动物的种群密度、现存生物量以及每公斤体重、每公斤代谢体重的物质和能量消耗,分析了牦牛种群在高寒草甸生态系统中的地位和作用。  相似文献   

2.
本文对栖息于高寒草甸优势种小哺乳动物--高原鼠兔(Ochotona curzoniae)种群的密度、食物的摄入、消化和同化、平均每日代谢率(ADMR)、每日能量收支(DEB)、种群的生产量(P)和呼吸量(R)进行了长期研究的基础上,按照 A=P+R的途径,估计了通过高原鼠兔种群的能流。  相似文献   

3.
通过对高寒草甸生态系统内香鼬、艾虎和大鵟3种食肉类稳定性碳和氮同位素比值(δ^13C和δ^15N)的测定,依据同位素的质量平衡原理和IsoSource软件计算得到:小型哺乳类在香鼬、艾虎和大鵟食谱中的分配比例分别为26.8%、27.0%和29.2%;雀形目成鸟的分配比例为22.3%、47.7%和69.1%;雀形目幼鸟为50.9%、25.6%和1.70%。3种食肉类的稳定性碳和氮同位素分布模式在二维空间上存在明显分割,由此说明.香鼬、艾虎和大鵟之间存在明显的食物资源分割现象,同时也反映了三者在高寒草甸生态系统内共存的基础。  相似文献   

4.
易现峰   《动物学研究》2005,26(1):1-7
通过对高寒草甸生态系统内香鼬、艾虎和大kuang 3种食肉类稳定性碳和氮同位素比值(δ[13]C和δ[15]N)的测定,依据同位素的质量平衡原理和IsoSource软件计算得到:小型哺乳类在香鼬、艾虎和大kuang食谱中的分配比例分别为26.8%、27.0%和29.2%;雀形目成鸟的分配比例为22.3%、47.7%和69.1%;雀形目幼鸟为50.9%、25.6%和1.70%。3种食肉类的稳定性碳和氮同位素分布模式在二维空间上存在明显分割,由此说明,香鼬、艾虎和大kuang之间存在明显的食物资源分割现象,同时也反映了三者在高寒草甸生态系统内共存的基础。  相似文献   

5.
本文在根田鼠(Microtus oeconomus)种群动态及种群生产量研究的基础上,探讨了根田鼠对天然食物选择、食物的摄入、消化率和同化水平、每日能量收支、年能量收支、并在种群生产量(P=Pg+Pr)和呼吸量(R)的基础上,按照A=P+R的途径,估计了通过根田鼠种群的能流。  相似文献   

6.
通过对高寒草甸生态系统内香鼬、艾虎和大(狂鸟)3种食肉类稳定性碳和氮同位素比值(δ13C和δ15N)的测定,依据同位素的质量平衡原理和IsoSource软件计算得到:小型哺乳类在香鼬、艾虎和大(狂鸟)食谱中的分配比例分别为26.8%、27.0%和29.2%;雀形目成鸟的分配比例为22.3%、47.7%和69.1%;雀形目幼鸟为50.9%、25.6%和1.70%.3种食肉类的稳定性碳和氮同位素分布模式在二维空间上存在明显分割,由此说明,香鼬、艾虎和大(狂鸟)之间存在明显的食物资源分割现象,同时也反映了三者在高寒草甸生态系统内共存的基础.  相似文献   

7.
本文研究“番北金”雏鸭的能量代谢和同化率。其结果:代谢率与体重呈线性负相关(r=-0.6834,y=3.3801-0.0037x)。每日代谢能消耗随体重增长而下降。雏鸭的能量摄入、可代谢能量、代谢能消耗和生长能量均随体重增长而增多。单位体重的能量摄入变动在2.07—2.67千焦/克之间。能量同化率,1周龄时(70.84%)较低,2—5周龄时则保持在82.60%—84.20%之间,6周龄时(89.36%)有所提高。在可代谢能量中,代谢能消耗占58.75%,生长能量消耗占41.25%。“番北金”鸭是金定鸭、北京鸭和番鸭三元杂交的杂种鸭。该鸭具有生长快、产肉性能好和饲料报酬高的特点,颇受群众欢迎。本文就“番北金”雏鸭的能量代谢和同化水平进行研究,为拟定该鸭饲料的能量标准提供参考依据。现将测定结果报告如下。  相似文献   

8.
戈峰  丁岩钦 《生态学报》1995,15(4):399-406
本文以能量为统一单位,以生理学时间为尺度,建立了计算世代重叠的棉蚜种群能流参数模型,分析和比较了不同播种时间、间套作、免耕和化学防治处理的棉田生态系统中棉蚜种群的生产力、摄入量及生态学效率。结果表明:(1)棉蚜种群能量生产的98%来自于伏蚜时期,而苗蚜与秋蚜不足2%;(2)播种期推后,苗蚜种群生产力、摄入量减少,而伏蚜、秋蚜的生产力、摄入量增加;套间作,使苗蚜、秋蚜种群生产力、摄入量减少,伏蚜种群的生产力、摄入量增加;(3)化学防治对棉蚜种群生产力、摄入量有一定的作用,其作用强度依农药品种及施药次数而异;(4)各类型棉田棉蚜种群的同化效率与净生态学效率变化幅度较小,而摄入利用效率变化幅度较大。由此进一步探讨了不同类型棉田棉蚜的管理对策。  相似文献   

9.
草原生态系统狭翅雏蝗种群的能量动态   总被引:3,自引:3,他引:3  
为揭示蝗虫在草原生态系统中的地位和作用,作者从一关键种着手,采用室内能量参数(取食量、排泄量、呼吸量、生产量)的测定结合野外自然种群数据的方法,讨论了3个植物群落(代表不同的退化程度)中狭翅雏蝗的能量动态。结果表明:(1)狭翅雏蝗种群的生产量(P)为1.1—2kJ/m~2,通过种群的能流(A)为3.4—6.6kJ/m~2,(2)其同化效率(A/C)为48%—58%,生态效率(P/C)为14%—18%,生长效率(P/A)为30%—32%;(3)狭翅雏蝗总摄食量(C)为6.9—13.8kJ/m~2,占地上初级生产量的0.21%—1.03%;另有0.21%—1.93%的牧草因蝗虫取食而掉落;狭翅雏蝗对牧草的压力表现为在越退化的草场,其压力越大。  相似文献   

10.
高寒草甸十种雀形目鸟类繁殖生物学的研究   总被引:7,自引:2,他引:5  
本文主要将作者1976年至1980年收集的高寒草甸10种常见的小型雀形目鸟类的繁殖特性作一概述,并对繁殖参数和影响繁殖的某些因素作一初步分析。此外,有关鸟类繁殖的许多指标,如种群中参加繁殖的雌体比例、繁殖期、产卵数、成活率等都是估测通过鸟类群落能量流的重要参数。因此,有关繁殖指标的数据将按估测能量流的要求处理(Wiens,1974),以供高寒草甸鸟类能量流的估测作为参考。  相似文献   

11.
青海海北地区艾虎的某些生态学特征及种群能量动态资料   总被引:2,自引:1,他引:1  
艾虎,又名艾鼬(Mvstela eversmanni Lesson)在生态系统的牧食食物链(grazingfood chain)结构上,属二级消费者。其在能流和物质循环中起着重要作用。 有关艾虎生态学研究,报道甚少。Ванников(1954)和Новиков(1956)仅作过一般简单的综述,嗣后,Сысоев(1966),лалваниявов(1968)。Попов等(1968),Маръпп(1974)Bednarz(1964),Bardu(1971)亦均系简报之类。至于其能量的研究,涉及者甚少。国内有关艾虎生态学研究,尚乏报道。  相似文献   

12.
The quantities of consumed food and water, quantity and moisture contents of faeces as well as quantity and concentration of excreted urine were determined in representatives of Martes—European pine marten (M. martes) and sable (M. zibellina)—as well as in polecat (Mustela putorius). Under the same cage conditions and free access to food, all three species have similar energy value of their daily diet. However, the level of drinking water consumption and the ratio between the daily total water and energy intake was reliably higher in both Martes species than in polecat. In addition, both marten and sable featured much higher rate of evaporation loss in the overall water balance and, consequently, a higher quantity of heat dissipated with evaporation as compared to polecat. Comparison of the obtained and previous data (Sokolov et al., 1995; Rozhnov, 1991) allowed us to propose that the mentioned differences are specific for representatives of Martes and Mustela genera irrespective of ecological specialization of particular species.  相似文献   

13.
The purpose of this study was to evaluate the effects of metabolic alkalosis on differentiated ratings of perceived exertion during intermittent high-intensity exercise. Six endurance-trained females participated as subjects in this investigation. Each subject underwent three separate experimental trials in which NaHCO3 was ingested in either a single (0.3 g NaHCO3/kg body wt) or periodic schedule (0.12 g NaHCO3/kg body wt initially, with 0.18 g/kg body wt distributed in equal doses before each 5-min exercise bout). Calcium carbonate served as a placebo control. An intermittent exercise protocol was used in which each subject rode a cycle ergometer at 90% maximum O2 consumption for 5 min. Within each acid-base condition, the exercise protocol was repeated three times with 10-min rest periods interspersed. Differentiated ratings of perceived exertion for the legs (RPE-L), chest (RPE-C), and overall body (RPE-O) were attenuated under alkalotic treatment relative to placebo control regardless of pattern of NaHCO3 administration. RPE-L, RPE-C, and RPE-O were negatively correlated to the bicarbonate concentration of venous blood. This investigation suggests that perception of effort during high-intensity intermittent exercise can be related to buffering capacity of the blood.  相似文献   

14.
The aim of the current investigation was to ascertain the role of ACTH and adrenal hormones on adrenomedullary and glycemic functions in soft-shelled turtles, Lissemys punctata punctata. All the experiments were carried out on sexually immature animals. Findings revealed that: (1) ACTH administration (0.5 IU/1.0 IU/2.0 IU per 100 g body wt. daily for 10 days) in all doses stimulated adrenomedullary function by increasing medullary cell nuclear diameter with elevations of norepinephrine, epinephrine and blood sugar levels. Only moderate and higher doses (50 microg/100 microg per 100 g body wt. daily for 10 days) of dexamethasone suppressed adrenomedullary activity and blood sugar level by reversing the changes to those of ACTH; the responses were dose-dependent. But these changes were no longer observed after ACTH treatment in dexamethasone (DMS) recipients (DMS: 100 microg/ 100 g body wt daily for the first 10 days and ACTH: 0.5 IU / 100 g body wt daily for the next 10 days); (2) Only moderate and higher doses (50 microg/100 microg per 100 g body wt daily for 10 days) of corticosterone increased adrenomedullary activity and blood sugar level and the responses were also dose-dependent. But aldosterone treatment in all doses (same as for corticosterone) had no significant effect on the adrenal medulla or blood sugar level; (3) Only moderate and higher doses of norepinephrine or epinephrine (same as for corticosterone) caused adrenomedullary atrophy with depletions of norepinephrine and epinephrine levels but elevated the glycemic level. The findings are briefly discussed.  相似文献   

15.
孕貂摄入日粮比孕前高8.03%,即摄入总能量高11.70%。产后,母貂摄入日粮与总能量的变化,近似S型曲线。孕貂体重与妊娠时间呈正相关,与泌乳时间呈负相关。妊娠期,孕貂每天摄入总能量超过呼吸量与粪便排出量之总和,则体重增加。泌乳期,母貂每天摄入总能量少于呼吸量、粪便排出量及泌乳量之总和,故体重减轻。  相似文献   

16.
Ray PP  Maiti BR 《Folia biologica》2002,50(3-4):115-120
The aim of the current work was to investigate the role of gonadotropins and female sex hormones on interrenal activity in soft-shelled turtles, Lissemys punctata punctata. 1) FSH treatment (3 microg/100 g body wt daily for 10 days) caused interrenal hypertrophy with increased nuclear diameter, raises of acid phosphatase and alkaline phosphatase concentrations, and depletions of cholesterol (except the free fraction) and ascorbic acid levels from the interrenal gland. However, LH treatment (3 microg/100 g body wt daily for 10 days) failed to produce any perceptible change in the interrenal activity. The combined treatments of FSH and LH (3 microg each/100 gm body wt daily for 10 days) produced no further change beyond that of FSH alone. 2) Estrogen treatment with the low dose (25 microg/100 g body wt daily for 10 days) had no effect, but with higher doses (50 microg or 100 microg/100 gm body wt daily for 10 days) is caused interrenal stimulation by inducing the same manifestations to those of FSH. The degree of manifestations was higher with the higher dose (100 microg daily) than that of the moderate dose (50 microg daily). Progesterone treatment with the low dose (25 microg /100 g body wt daily for 10 days) had no significant effect, but with the moderate (50 microg daily) and higher (100 microg daily) doses suppressed interrenal activity by showing the reverse changes to those of estrogen. The degree of manifestations was higher with the higher dose than that of the moderate one. The combined treatments of estrogen and progesterone (100 microg each/100 g body wt daily for 10 days) caused interrenal stimulation but to a lesser extent than that of estrogen alone. The findings are briefly discussed.  相似文献   

17.
The study measured the concentration of Cd, Cr, Pb, Cu, and Zn in various fish tissues (muscle, gills, and liver) of 18 fish species (C. gachua, C. marulius, C. punctatus, C. nama, C. ranga, H. fossilis, C. batrachus, P. ticto, P. phutunio, L. rohita, L. calbasu, L. gonius, T. putitora, T. tor, R. rita, G. chapra, H. ilisa, and N. botia) collected from Ganga river. It is the survey regarding metal concentration in fish tissues increasing day by day. The metal concentration in different fish tissues varied on the following range: Cu (0.45–8.54 µg/g wet wt), Zn (0.07–2.2 µg/g wet wt), Pb (0.20–2.62 µg/g wet wt), Cd (0.07–2.32 µg/g wet wt), and Cr (0.09–1.74 µg/g wet wt). The results show the concentration of Pb, Cd, and Cr metals to be higher than internationally recommended standard limits (as determined by the WHO and FAO) and other similar studies. Generally, higher concentrations of metals were found in liver and gills than muscles. Despite lower estimated daily intake (EDI) of fish in the area (per recommended daily allowance guidelines), values of daily average consumption were lower than the recommended values by FAO/WHO/EFSA, and in fish samples these were below the provisional permissible levels for human consumption. The continuous exposure to heavy metals has been linked to the development of mental retardation, kidney damage, various cancers, and even death in instances of very high exposure in human body.  相似文献   

18.
CCK and ghrelin exert antagonistic effects on ingestive behavior. The aim of the present study was to investigate the interaction between ghrelin and CCK administered peripherally on food intake and neuronal activity in specific hypothalamic and brain stem nuclei, as assessed by c-Fos-like immunoreactivity (c-FLI) in nonfasted rats. Ghrelin (13 microg/kg body wt) injected intraperitoneally significantly increased the cumulative food intake when measured at 30 min and 1 h after injection, compared with the vehicle group (2.9 +/- 1.0 g/kg body wt vs. 1.2 +/- 0.5 g/kg body wt, P < 0.028). Sulfated CCK octapeptide (CCK-8S) (2 or 25 microg/kg body wt) injected simultaneously blocked the orexigenic effect of ghrelin (0.22 +/- 0.13 g/kg body wt, P < 0.001 and 0.33 +/- 0.23 g/kg body wt, P < 0.0008), while injected alone, both doses of CCK-8S exerted a nonsignificant trend to reduce food intake. Ghrelin (13 microg/kg body wt ip) markedly increased the number of c-FLI-positive neurons per section in the arcuate nucleus (ARC) compared with vehicle (median: 31.35 vs. 9.86, P < 0.0001). CCK-8S (2 or 25 microg/kg body wt ip) had no effect on neuronal activity in the ARC, as assessed by c-FLI (median: 5.33 and 11.21 cells per section), but blocked the ghrelin-induced increase of c-fos expression in this area when both peptides were administered simultaneously (median: 13.33 and 12.86 cells per section, respectively). Ghrelin at this dose had no effect on CCK-induced stimulation of c-fos expression in the paraventricular nucleus of the hypothalamus and the nucleus of the solitary tract. These results suggest that CCK abolishes ghrelin-induced food intake through dampening increased ARC neuronal activity.  相似文献   

19.
粘虫幼虫密度对幼虫食物利用率的影响   总被引:5,自引:4,他引:1  
罗礼智  徐海忠 《昆虫学报》1995,38(4):428-435
本文对粘虫Mythimna separata(Walker)不同幼虫密度下(1头/瓶、15头/瓶、30头/瓶)5龄至预蛹和6龄至预蛹的幼虫食物取食量、粪便排泄量、近似消化率、体重增长和粗生长效率等进行了研究。结果表明:幼虫的食物取食量、粪便排泄量随幼虫密度的增加而加大,表明群居或幼虫密度的增加可使幼虫的取食量增加从而使为害加重。但是,幼虫的体重增长则随幼虫密度的增加而下降,这是因为近似消化率和粗生长效率也随幼虫密度的增加而下降的缘故。由此认为,食物利用率下降是高密度条件下粘虫个体较小的主要原因之一。但是,些效应均随幼虫密度影响的消失而消失。  相似文献   

20.
作者采用常规生化分析法测定草食性鱼类天然食料(七种水生高等植物)的生化成分和能值。在实验室特定条件下测定了草鱼和团头鲂的系列体重组对七种水生高等植物的最大摄食量和消化率。1.七种水生高等植物的生化成分的含量和能值的分析结果表明,菹草、黄丝草、聚草、苦草、小茨草、轮叶黑藻和紫背浮萍的水分百分含量范围为80.85—92.72%、蛋白质为1.69—4.96%、脂肪为0.35—1.09%、灰分为0.98—2.6%、纤维素为0.66—2.17%、无氮浸出物为2.3—9.95%。七种水生植物的蛋白质均含有常见十七种氨基酸,包括鱼体必需氨基酸九种和非必需氨基酸八种。其中菹草的氨基酸含量最高(36.63mg/g 湿重)、苦草最低(12.92mg/g 湿重);菹草的能值最高(3.36KJ/g 湿重)、小茨藻最低(1.28KJ/g 湿重)。2.草鱼、团头鲂对七种水生植物的最大摄食量(Y,g/24h)及消化率(Y,%)与鱼体重(X,g)相关显著,关系式为 Y=aX~b。从结果表明,随着鱼体重的增加,鱼对七种食料的相对摄食量下降(绝对摄食量上升),消化率提高。草鱼的最大摄食量一般比团头鲂高,而消化率一般比团头鲂低。    相似文献   

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