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1.
谢帆  王素珍 《生态学报》1983,3(1):89-90
常绿阔叶林是我国亚热带的地带性植被。井冈山区蕴藏着相当丰富的典型的常绿阔叶林。该山区的地理位置是北纬26°36′—29°00′,东经113°50′—114°20′之间,地处中亚热带湿润季风气候,土壤是山地红黄壤。据作者采集所见,整个井冈山区共有野生乔木130种,隶属于45科,70属。常绿阔叶林主要覆盖在海拔1,000—1,300米以下的低山丘陵地上。 本文的目的在于初步揭示常绿阔叶林更新的某些规律。野外工作的重点放在调查样地内  相似文献   

2.
树鹨数量及繁殖的初步观察   总被引:1,自引:1,他引:0  
1986—1988年的4—10月,在山西庞泉沟国家级自然保护区,对树鹨(Anthus hodgsoni)的数量和繁殖进行了观察,现将资料整理报道如下。工作地点和方法本区位于山西省吕梁山脉中段,地处交城和方山两县交界(东经111°21′—111°33′,北纬37°45′—37°55′)。其植被、气候等资料已有报导〔1〕。将全区划为4个植被类型即:一、八水沟农作疏林灌丛区,海拔1600—1900米。二、大路峁针阔混交林区,海拔1900—2000米。三、罗板沟针叶落叶林区,海拔2200—2600米。四、云顶山亚高山草甸区,海拔2600—2800米。在上述4个植被带中,选定一条长2000米的固定路…  相似文献   

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后河自然保护区位于鄂西南五峰土家族自治县境内,北纬30°03′至30°08′,东经110°30′至110°35′,面积约1万公顷。保护区内海拔最高1934m,最低980m,整个地势周围高,中间低。区内山峦重叠,沟壑纵横,地形地貌复杂。本区属亚热带气候,年平均气温131℃,年积温为38079—49843℃,无霜期约250天,年降水量约1460mm,年相对湿度为76%。该区发育的地带性植被类型为中亚热带常绿阔叶林与落叶混交林。经调查,这里有维管植物2002种,隶属810属190科。其中蕨类19…  相似文献   

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白水江自然保护区位于东经104°18′—105°25′,北纬32°35′—33°50′;总面积198488公顷(核心区90358公顷,实验区108310公顷)。全境为南秦岭山地,区内山峦重迭,山间河谷深陷。区内水系为长江水系。气候除河谷属亚热带湿润气候外,大部分为暖温带湿润气候,年平均温度15.9℃,最高37.5℃,最低—7.4℃。无霜期262天左右,年均降水量442毫米。植被呈明显垂直分布,可分下列四个植被带:一、低山常绿、落叶林带:海拔1600米以下,有大面积农耕区和居民点,植被以次生阔叶林为主。常见有麻栎、山楠、马桑、蔷薇等。二、中山阔叶林和混交林带:海拔1600—…  相似文献   

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一、自然环境概况江苏位于东经116°22′—121°55′,北纬34°46′—35°07′之间,东濒黄海,地跨暖温带、北亚热带和中亚热带三个生物气候带。灌溉总渠以北为落叶阔叶林地带,年均温13.8℃,一月均温-0.7℃,极端最低均温-13.4℃,年降水量912毫米。境内东北部有胶东、鲁南山地延伸入境的丘陵低山,一般海拔100—200米,连云港的云台山达625米,为全省最高岭。地带性土类为棕壤。植被受海洋性气候影响,并有复杂山岳地貌的有利生  相似文献   

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河南鸡公山国家级自然保护区昆虫多样性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
2018年5-10月在河南鸡公山国家级自然保护区内开展了昆虫多样性调查工作,共采集到昆虫2110头,分别隶属于15目106科880种.其中以鳞翅目Lepidoptera(274种)、鞘翅目Coleoptera(206种)、半翅目Hemiptera(185种)和膜翅目Hymenoptera(89种)为主,种数占比分别为31.14%、23.41%、21.02% 和10.11%,其他类群(共126种)占14.32%.9种不同植被类型中昆虫群落多样性分析结果表明:针阔混交林、阔叶混交林、灌草丛和马尾松林中昆虫群落多样性的各项指标均较高,落羽杉林和杉木林次之,草甸、水生植被和竹林最低.在区系组成上,古北种昆虫最丰富,有372种,占总数的42.26%;其次是东洋种,有269种,占30.57%;广布种最少,有239种,占27.15%.在昆虫群落相似性方面,总体上两种混交林与其他森林类型的相似性较高,而竹林、草甸和水生植被与其他森林类型的相似性较低.  相似文献   

7.
浙西南山区蝗虫的生态地理研究   总被引:1,自引:0,他引:1  
<正> 丽水地区位于浙江西南部(北纬29°25′—28°57′,东径118°41′—120°24′),地形复杂,山地面积占全区总面积的87%。森林植被属中亚热带阔叶林区,沿江平原、丘陵以水稻、麦类、甘薯等粮食作物为主。 我们先后在有代表性的平原、半山区、山区和高山区调查采集,其中包括凤阳山(1,921米)和九龙山自然保护区(1,724米)及百山祖(1,857米)三座高峰的考察,对全区蝗虫种类、地理分布及生态适应性方面作了一些探讨。 一、种类组成 全区已鉴定出蝗虫种名的计38种,隶属于4亚科28属(见统计表)。 1.斑腿蝗亚科数量最多,计13属19种。其  相似文献   

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分析了中国蛱蝶科已知324种昆虫的分布与区系组成,主要由古北区、东洋区、古北一东洋区共有种类组成,共计309种,占总数的95.37%;其种类组成与澳洲区、新北区有明显差异;特有种类较少,占总数的12.65%;广布种很少,仅占1.74%。同时统计分析了324种蛱蝶在我国各省的贫富指数。  相似文献   

9.
关于白蜡虫在我国的地理分布,王辅(1963,1978)认为:“白蜡虫以北纬26°-32°40′之间为其适生地带,26°以南或33°以北均不适其生存。”近年来,我们通过考察认为:在北纬26°以南和33°以北地区,均有白蜡虫自然种群存在。 一、鞍山地区自然概况 鞍山位于东径123°,北纬41°10′,辽河平原东南边缘,东邻千山山脉,南与辽宁半岛相连;海拔20—708米;本地属大陆性半湿润型温带气候,年均气温8.8℃,最冷月均温-10.2℃,极端最低气温-30.4℃,极端最高气温36.9℃,≥10℃年积温3536.3℃,相对湿度63%,年降水量713.5毫米;本市海拔21.6米;植被为暖温带落叶阔叶林。  相似文献   

10.
 本文对陕西省化龙山植被的垂直分布特点进行了初步研究。文中采用了数量分类结合对群落生态特点及区系组成的分析,划分出森林植被垂直带如下:常绿、落叶阔叶混交林带,海拔1600m以下;落叶阔叶林带,海拔1600—2200m;亚高山针叶林带,海拔2200—2917m。  相似文献   

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A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.  相似文献   

13.
2-Dimethylaminomethylene-1-benzosuberone 1 was coupled with diazotized aniline derivatives to afford a series of the hitherto unreported 2-arylazo-1-benzosuberones 3ai. The tautomeric structure and the effect of substituents on the tautomeric form (s) of the products 3ai were discussed. Similar coupling of the enaminone 1 with diazonium salts of heterocyclic amines gave the respective fused azolotriazino-benzosuberones. Some of the newly synthesized compounds showed potent antimicrobial, anti-HCV, antioxidant, antitumor (as topoisomerase I inhibitors), and antimicrobial activities.  相似文献   

14.
The Precautionary Principle is in sharp political focus today because (1) the nature of scientific uncertainty is changing and (2) there is increasing pressure to base governmental action on more “rational” schemes, such as cost-benefit analysis and quantitative risk assessment, the former being an embodiment of ‘rational choice theory’ promoted by the Chicago school of law and economics. The Precautionary Principle has been criticized as being both too vague and too arbitrary to form a basis for rational decision making. The assumption underlying this criticism is that any scheme not based on cost-benefit analysis and risk assessment is both irrational and without secure foundation in either science or economics. This paper contests that view and makes explicit the rational tenets of the Precautionary Principle within an analytical framework as rigorous as uncertainties permit, and one that mirrors democratic values embodied in regulatory, compensatory, and common law. Unlike other formulations that reject risk assessment, this paper argues that risk assessment can be used within the formalism of tradeoff analysis—a more appropriate alternative to traditional cost-benefit analysis and one that satisfies the need for well-grounded public policy decision making. This paper will argue that the precautionary approach is the most appropriate basis for policy, even when large uncertainties do not exist, especially where the fairness of the distributions of costs and benefits of hazardous activities and products are a concern. Furthermore, it will offer an approach to making decisions within an analytic framework, based on equity and justice, to replace the economic paradigm of utilitarian cost-benefit analysis.  相似文献   

15.
We compared the cardiovascular effects evoked in conscious dogs by 1) submaximal exercise; 2) infusion of dobutamine (40 micrograms X kg-1 X min-1); and 3) infusion of a combination of atropine (0.15 mg/kg), norepinephrine (0.19 micrograms X kg-1 X min-1), and epinephrine (0.05 micrograms X kg-1 X min-1). Myocardial O2 demand, as estimated by the double product (heart rate X systolic blood pressure), was similar during all three interventions. Cardiac output and heart rate increased significantly (P less than 0.05) during each of the three interventions. Arteriovenous O2 difference and total body O2 consumption, however, increased only during submaximal exercise. Although myocardial blood flow increased similarly during each of the three interventions, blood flow to skeletal muscle and the tongue increased only during exercise. Exercise and the combined infusion of atropine, norepinephrine, and epinephrine produced similar increases in blood flow to the diaphragm and similar decreases in blood flow to the stomach. These changes in blood flow were associated with appropriate changes in vascular resistance. Additionally, blood flow to the brain, kidney, adrenal glands, liver, and intestine did not change during any of the three interventions. Thus, in dogs, submaximal exercise, infusion of dobutamine, and infusion of a combination of atropine, norepinephrine, and epinephrine to evoke a given level of estimated myocardial O2 consumption produce similar increases in cardiac output, heart rate, and myocardial blood flow. In contrast, the changes in total body O2 consumption, arteriovenous O2 difference, regional blood flow, and regional vascular resistance that occur during each of these three interventions are different.  相似文献   

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Indians, Markets, and Rainforests: Theory, Methods, and Analysis. Ricardo A. Godoy. New York: Columbia University Press, 2001. 274 pp.  相似文献   

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《Journal of lipid research》2017,58(12):2289-2298
This study addresses the question: why do rats get cataracts at 2 years, dogs at 8 years, and whales do not develop cataracts for 200 years? Whale lens lipid phase transitions were compared with the phase transitions of other species that were recalculated. The major phospholipids of the whale lens were sphingolipids, mostly dihydrosphingomyelins with an average molar cholesterol/phospholipid ratio of 10. There was a linear correlation between the percentage of lens sphingolipid and lens lipid hydrocarbon chain order until about 60% sphingolipid. The percentage of lens sphingolipid correlated with the lens lipid phase transition temperature. The lifespan of the bowhead whale was the longest of the species measured and the percentage of whale lens sphingolipid fit well in the correlation between the percentage of lens sphingolipid and lifespan for many species. In conclusion, bowhead whale lens membranes have a high sphingolipid content that confers resistance to oxidation, allowing these lenses to stay clear relatively longer than many other species. The strong correlation between sphingolipid and lifespan may form a basis for future studies, which are needed because correlations do not infer cause. One could hope that if human lenses could be made to have a lipid composition similar to whales, like the bowhead, humans would not develop age-related cataracts for over 100 years.  相似文献   

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