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1.
我国的黑颈鹤与研究   总被引:5,自引:1,他引:4  
黑颈鹤芷云贵高原和青藏高原分布范围在北纬26°43′—39°,东径79°45′—104°18′之间;垂直分布,繁殖区在海拔2500—5000米,越冬区在海拔2200—4000米;数量在800只左右。 繁殖地四川若尔盖4—9月与越冬地贵州草海地区10—3月的主要气候指标基本相似。 在自然条件下,黑颈鹤的食物主要取食植物,一般不寻觅动物性食物。  相似文献   

2.
东北边境地带吸血蠓的区系和生态研究   总被引:6,自引:0,他引:6  
刘国平  虞以新 《生态学杂志》1992,11(4):18-21,40
我国东北吉林省和黑龙江省的边境地带共有18个县区,东起于吉林省珲春县,北止于我国最北端的黑龙江省漠河县,全长约2500km,位于东经122°4′—129°50′,北纬53°—41°25′之间,一般海拔500—1000m,年平均降水量300—700mm,昆虫地理区划属东北区大兴安岭亚区和长白山亚区。多年来,吸血蠓对边境  相似文献   

3.
我国金花茶组植物的地理分布   总被引:12,自引:0,他引:12  
苏宗明  莫新礼   《广西植物》1988,(1):75-81
世界产金花茶组植物22种,其中我国20种,特有18种,仅产广西。其分布区在北纬21°30′—23°40′,东经106°40′—108°35′,北界基本上与广西北热带半常绿季雨林、湿润雨林地带北界吻合。该组植物分布于石灰(岩)土的13种,红壤的7种。它们出现的地段比较固定,天然林下,沟谷或溪边处,相对高度10—15米;峰丛圆洼地底部和荫蔽的坡面下部。该组植物个体最多的地区(几何中心)一个在防城县,一个在龙州县;种类最多的地区(最大变异中心)一个也在龙州县,9种,一个在扶绥县,7种。该分布区从南到北分化成六个小分区。其垂直分布一般在海拔700米以下。水平分布种的更替表现为:北纬21°31′为小瓣金花茶等五种;北纬22°10′—22°45′为鼻岗金花茶等八种更替;北纬22°50′为顶生金花茶等三种更替;北纬23°40′为平果金花茶更替。金花茶分布幅度最宽,可由北纬21°31′到22°55′。在土山,东西以东经107°30′为界,以东为金花茶等四种,以西为小瓣金花茶等二种。  相似文献   

4.
暗腹雪鸡的繁殖及食性   总被引:7,自引:0,他引:7  
常城  刘乃发 《动物学报》1993,39(1):107-108
暗腹雪鸡 Tetraogallus himalayensis 属国家保护动物,郑作新等(1978)、沈孝宙等(1963)对其生态仅有零星报道。1984年4月至 1989年 5月,我们在甘肃东大山(39°00′—39°04′N;100°45′—100°51′E.)、冷龙岭(39°34′—38°14′N;101°49′—102°22′E.)和野马山(39°40′—39°50′N;95°15′—95°45′E.)对暗腹雪鸡青海亚种 T.h.koslowi 的繁殖和食性进行了研究。 一、暗腹雪鸡繁殖期的生态分布 在东大山,暗腹雪鸡繁殖期主要分布于海拔 2 400—3 200m的亚高山草甸、山地草原和荒漠草原。其中,山地草原是营巢区,余为觅食区。冷龙岭植被与东大山相似,暗腹雪鸡的生态分布也类似。野马山植被单调,暗腹雪鸡仅分布于山地草原。  相似文献   

5.
大邑县位于成都平原西部边缘,地跨北纬30°25′至30°49′,东经102°54′至103°45′。境内地形复杂,山势陡峻,系成都平原向西北高原过渡地带。而高山无人烟地区多峡谷,并有暖湿海洋气流顺坡谷而上,因而气候温湿、林木生长茂盛,植物垂直分布明显,在海拔1500—2000米范围内,主要以樟科、槭树科、壳斗科、胡桃科等常绿或落叶树种为主。海拔2000—3000米内,以松科的冷杉、紫果云杉和桦木科的红桦为主。海拔3500米以上为高山杜鹃林及高山草甸。竹类资源丰富,据调查,在海拔1000—1500米内,通常生长着白夹竹、刺竹及其它杂竹和少量的丰实箭竹,纯林…  相似文献   

6.
一、云南植胶区的自然地理条件云南橡胶种植区位于云南高原南部,北纬20°09′—24°59′,东经93°31′—105°08′,海拔100—1000m之间的热带季风地区。包括文山、红河、思茅、西双版纳、临沧和德宏地区  相似文献   

7.
梵净山自然保护区蕨类植物区系   总被引:15,自引:2,他引:13  
邓莉兰  杨传东   《广西植物》1991,11(1):44-50
梵净山属武陵山脉主峰,位于贵州省东北部,东经108°45′55″—108°48′30″,北纬27°49′50″—28°1′30″,海拔500—2493.4米,面积约600平方公里,其蕨类植物区系组成共39科83属182种。在区系结构}二表现出下列几个一般的特征:(1)种系密度大,成分多样1(2)温带性质,是泛北极区系的一部分,与热带地区有一定的亲缘联系;(3)特有现象明显;(4)是东南亚成分(含中国一喜马拉雅和中国—日本成分)分布中心的一部分:是中国—喜马拉雅和中国一日本成分交汇中心的一部分;(5)属内种系贫乏;(6)与华东地区的关系密切。  相似文献   

8.
四川卧龙自然保护区天牛区系及其起源与演化的研究   总被引:2,自引:0,他引:2  
卧龙自然保护区位于东经102°52′—103°24′,北纬30°45′—31°25′。据1980—1983年的调查材料,该自然保护区的天牛共有45属、73种,其中,东洋种47种,占64.4%;古北种10种,占13.7%;广布种5种,占6.8%;特有种11种,占15.1%。从区系组成上看,这个地区似位于东洋区与古北区的过渡带上,并且有靠近东洋区的趋势。高道蓉等(1981)在对峨嵋山(东经103°20′,北纬29°31′)白蚁区系的研究中也认为,峨嵋山位于这条过渡带上。然而,这两个地区的地带性植被、气侯和昆虫组成都与古北区迥然不同,而且,这两个地区的古北种都分布在高海投带上。因此,卧龙自然保护区应属东洋区;昆虫的地理区划主要应以地带性植被、气侯和昆虫组成为依据。 卧龙天牛的垂直分布可分为四个带:(1)亚热带常绿阔叶林带(海拔1120—1600米);(2)常绿、落叶阔叶混交林带(海拔1600—2000米);(3)针、阔叶混交林带(海拔2000—2600米);(4)亚高山针叶林带(海拔2600—3600米)。第1带(基带)东洋种占88.9%,没有古北种;第2带东洋种占50%,古北种占14.3%;第3带东洋种占44.4%,古北种占33.3%;第4带全部为古北种。与中国东部的植被相似,天牛分布每向上移一个垂直带,其成员在水平上也向北移一个带。研究结果还表明,在水平方向分布广的种类在垂直方向也表现  相似文献   

9.
马家山自然保护区(105°28′~105°40′E,32°50′~32°56′N)属秦岭西段的南坡山地。采用样线调查法和访问调查法,于2004年10~11月,对该保护区大中型兽类(包括灵长类、食肉动物和偶蹄动物)的资源、区系和生态分布进行了研究。该保护区共有23种大中型兽类,其中属我国Ⅰ级、Ⅱ级重点保护动物的兽类分别有5种和9种。它是秦岭物种多样性保护的关键地区之一。金丝猴和猕猴在此同域分布,大熊猫和羚牛四川亚种也分布于此地,该保护区是这4个珍稀濒危物种的一个新分布区。区内的23种兽类中没有古北界的区系成分,而属于东洋界成分的兽类有17种,占73.9%;其余6种为广布种,占26.1%。分析该区域23种兽类的生态分布发现,常绿落叶阔叶混交林、落叶阔叶林和针阔叶混交林中分别有16种、20种和12种动物活动。这些物种的垂直分布幅度有很大的差异。垂直分布幅度在海拔高差1000 m以上、500~1000 m、500 m以下的物种分别有5种、13种和5种。区内不同海拔带的兽类物种数随海拔升高的变化比较平稳,没有表现出明显上升或下降的规律性变化。  相似文献   

10.
山东白头鹎的一些生态观察   总被引:3,自引:3,他引:0  
据记载白头鹎Pycnontus sinensis的分布区,北至山东南部郯城(东经118°17′—118°40′、北纬34°251—34°57′)……。1984—1988年作者在山东省泰山(东经117°5′—117°24′、北纬36°5′—36°75′)、徂徕山(东经117°16′—117°20′、北纬36°02′—36°07′)的连续观察和冬季采到的标本,得知此鸟在上述两地为留鸟。常在海拔500米以下的低山一带活动,多停落在树的  相似文献   

11.
 以荒漠绿洲过渡带植被为研究对象,采用地统计理论与方法,以优势植物泡泡刺(Nitraria sphaerocarpa)和红砂(Reaumuria soongorica)种群为例,采用一个样地内2 500个10 m×10 m小样方中获取的植物盖度数据来研究采样尺度和划区方式对荒漠植被空间异质性的影响。其中尺度效应研究的思路是:一是保持粒度(样方)不变,增加幅度(样地)分析其对空间异质性的影响;二是保持幅度不变,改变粒度进行分析。划区效应是在样地尺度(500 m×500 m)上,把整块样地数据聚合成10 m×200 m、20 m×100 m、40 m×50 m、50 m×40 m、100 m×20 m和200 m×10 m等不同形状和不同方向的网格进行地统计分析。结果表明:荒漠绿洲过渡带植被空间异质性受采样尺度和划区方式影响显著。当样地面积小于200 m×200 m 时,所获取的数据不能真实反映泡泡刺种群的空间异质性;当样地面积小于100 m×100 m 时,所获取的数据不能真实反映红砂种群的空间异质性。调查泡泡刺和红砂种群的空间格局时,样方面积在20 m×20 m到30 m×30 m较为合适。植被空间异质性参数对划区方式的敏感性较强,其中泡泡刺种群的敏感性高于红砂种群。  相似文献   

12.
贵州茂兰的叶附生苔类   总被引:6,自引:0,他引:6  
吴鹏程  林齐维   《广西植物》1988,(4):335-338
贵州南部荔波县茂兰地区的亚热带喀斯特森林为一类罕见的植被类型,散布在约210km_2的洼地内。3科、13属和31种叶附生苔类植物发现于这一特殊的生境中,显然由于受局部环境的长期影响,其中孕育着一些特有的种类。  相似文献   

13.
14.
Although Spirogyra Link (1820) is a common mat‐forming filamentous alga in fresh waters, little is known of its ecology. A 2‐year field study in Surrey Lake, Indiana, showed that it grew primarily in the spring of each year. The population consisted of four morphologically distinct filamentous forms, each exhibiting its own seasonal distribution. A 45‐μm‐wide filament was present from February to late April or early May, a 70‐μm‐wide form was present from late April to mid‐June, a 100‐μm‐wide form was present from February to mid‐June, and a 130‐μm‐wide form appeared only in February of 1 of 2 study years. The 70‐ and 100‐μm‐wide forms contributed to the peak amount of biomass observed in late May and early June. Multiple regression analysis indicated that the presence of the 45‐, 70‐, and 100‐μm‐wide forms was negatively correlated with temperature. Presence of the 130‐μm‐wide form was negatively correlated with irradiance. Isolates of these filament forms were exposed to temperature (15, 25, and 35° C)/irradiance (0, 60, 200, 400, 900, and 1500 μmol·m?2·s?1) combinations in the laboratory. Growth rates of the 45‐μm‐wide form were negative at all irradiances at 35° C, suggesting that this form is susceptible to high water temperatures. However, growth rates of the other forms did not vary at the different temperatures or at irradiances of 60 μmol·m?2·s?1 or above. Net photosynthesis was negative at 35° C and 1500 μmol·m?2·s?1 for the 100‐ and 130‐μm‐wide forms but positive for the 70‐μm‐wide form. All forms lost mat cohesiveness in the dark, and the 100‐ and 130‐μm‐wide forms lost mat cohesiveness under high irradiances and temperature. Thus, the morphological forms differed in their responses to irradiance and temperature. We hypothesize that the rapid disappearance of Spirogyra populations in the field is due to loss of mat cohesiveness under conditions of reduced net photosynthesis, for example, at no to low light for all forms or at high light and high temperatures for the 100‐ and 130‐μm‐wide forms. Low light conditions can occur in the interior of mats as they grow and thicken or under shade produced by other algae.  相似文献   

15.
Abstract— The possible existence of type C MAO, distinct from type A and type B, in circumventricular structures of rat brain was examined by histological studies on the inhibitory effects of clorgyline. a preferential type A MAO inhibitor and deprenyl, a preferential type B inhibitor, on enzyme. Brain slices were preincubated with the inhibitors and then incubated with 5-HT, the substrate for type A MAO, and stained for MAO activity. Deposits of the product formazan were detected in circumventricular structures of slices of brain preincubated with clorgyline and deprenyl at concentrations of 10-7–10-4m at room temperature for 5 min. When the slices were preincubated with either of these inhibitors at room temperature for 60 min, strong activity was observed in this region, whereas when they were preincubated with either 10-5m -clorgyline or 10-5m -deprenyl for 20 and 30 min at 37°C, no MAO activity was seen in any region of the brain. Thus, at the higher preincubation temperature, lower concentrations of each inhibitor and a shorter preincubation period were required for inhibition of the enzyme. Preincubation for 60 min at 37°C with a combination of 10-7m -clorgyline and 10-8m -deprenyl did not inhibit the enzyme in the circumventricular region completely, but at the same temperature, concentrations of 10-7m of both inhibitors inhibited the enzyme completely in 10min, Thus the effects of the inhibitors are synergistic. These results indicate that the inhibitory effects of the two inhibitors on the enzyme in circumventricular structures of the brain is time- and temperature-dependent. Moreover, the activity seems to be sensitive to deprenyl even when 5-HT is used as substrate. The results do not support the idea of the existence of type C MAO, distinct from type A and type B MAO.  相似文献   

16.
分析鼎湖山3种植被类型生态系统水文的长期连续观测资料,采用时空互代的方法,得到如下一些结果:1)鼎湖山自然保护区东沟集水区产水量达到降水量的66.5%,日径流量高峰的出现相对降水的发生滞后1d左右。2)地下水位平均稳定在2.22m,最低为2.84m,最高为1.14m。1999、2000、2001、2002和2003年地下水位平均值分别为2.38,2.27,2.08,2.13和2.11m。鼎湖山东沟集水区每日地下水位与前16d每一天的降水量相关。3)随着时间推移3种不同的植物群落中土壤含水量都有减少的趋势。季风林(p<0.01)和混交林(p<0.05)的土壤含水量减少趋势具有统计上的显著性,松林除外。4)鼎湖山3个处于不同演替阶段的植物群落其穿透水量与大气降水皆呈线性相关,它们的R2值随演替的进展而减小。穿透水占大气降水的比例也随演替进展而减少,松林、混交林和季风林分别为83.4%、68.3%和59.9%。松林、混交林和季风林的树干茎流占大气降水的比例分别为1.9%、6.5%和8.3%。树干茎流和胸径的关系受控于整个群落整体的影响而不仅仅是某个单一物种,并且群落的郁闭程度和结构是影响降水在林内再次分配的关键因素。季风林2月大气降水28.7mm林冠截流率为83.3%,而在大气降水为297.8mm的6月林冠截留率仅为18.9%,并且随着植物群落的演替,从松林、混交林到季风林的过程中林冠截留逐渐增大。  相似文献   

17.
Human casein was separated by gel filtration on a column of Sephadex G–200 with 0.1 m Tris buffer (pH 8.5) containing 1.0 m NaCl. The effluent which increased in turbidity at 25°C was centrifuged at 25,000 × g for 30 min and the precipitate was obtained as Fraction 6. After centrifugation, the effluent was separated into 5 elution fractions.

Disc gel electrophoretic patterns of each fraction showed occurrence of secondary bands other than major bands especially in Fractions 3, 4 and 5. The casein solutions unheated and heated at 100°C for 5 and 10 min were kept at 5°C for 5 days. No marked changes of electrophoretic pattern were observed among these casein solutions. However, when a casein solution heated at 100°C for 5 min was chroma to graphed under the same condition, secondary bands also appeared.  相似文献   

18.
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   

19.
One-month-old fruits of Acer ginnala with winged pericarp attached gave 44% germination and this was not increased by cold treatment at 4°C for 0, 10, 20, or 30 days, gibberellic acid treatment at 0, 1, 10, 100 or 1000 mg litre-1, or ethephon treatment at 0, 2, 20, 200 or 2000 mg litre-1. After 6 months of storage at 20–25 °C, germination of untreated fruits fell to 5% but could be restored to that of 1-month-old fruits by incubation at 4 °C for 30 days. After 9 months storage, no germination occurred in untreated fruits. Cold treatment (30 days at 4 °C partially restored germination (26%). Treatment with either gibberellic acid (1000 mg litre-1) and 30 days at 4 °C (40%) or ethephon (100 mg litre-] and 30 days at 4 °C improved germination (69%). The combination of all three treatments, i.e. 100 mg litre-1 gibberellic acid, 100 mg litre-1 ethephon and 30 days at 4 °C, optimised germination (86%). Thus, dormancy of A. ginnala developed during storage but could be reversed by a combination of treatment with low temperature and growth regulators. The highest germination (86%) was achieved after low temperature and growth regulator treatment of stored fruit.  相似文献   

20.
The influence of oil type on the ability of excipient emulsions to improve the solubility, stability, and bioaccessibility of curcumin was examined. Oil-in-water emulsions were prepared using coconut, sunflower, corn, flaxseed, or fish oils. These excipient emulsions were then mixed with powdered curcumin and incubated at 30 or 100 °C. For all oils, more curcumin was transferred from powder to excipient emulsion at 100 °C (190–200 μg/mL) than at 30 °C (30–36 μg/mL), which was attributed to increased curcumin solubility with temperature. Oil type influenced the stability and bioaccessibility of curcumin when excipient emulsions were exposed to simulated gastrointestinal tract conditions, which was attributed to differences in the molecular composition and physicochemical properties of the oils. Overall, the use of fish oil led to the highest effective curcumin bioavailability (38 %). This study provides valuable information for optimizing excipient emulsions to increase curcumin bioavailability in food, supplement, or pharmaceutical applications.  相似文献   

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