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英德西南旅游区水源河流水质与浮游生物群落特征 总被引:1,自引:0,他引:1
通过野外采样及实验室分析,调查了英德市西南旅游区水源河流上、中、下游的水质状况及浮游生物的多样性。结果表明,(1)英德市西南旅游区上、中、下游河段亚硝酸盐、氨、硝酸盐、总氮、镉、铅、铬、镍、铜、锌的含量低于国家标准,铝、钙、钴、铁、钼、硒的含量超过国家标准,而总磷、砷、镁、锰的含量在部份区段已超过国家标准;(2)浮游动物种类的个体数在整条河中以桡足类最多,上游通天岩中浮游动物个体数最多,下游碧落湖浮游动物多样性最低;此次调查总共发现68种浮游植物,其中主要集中在下游碧落湖,在中游碧落洞绿藻、蓝藻、硅藻总个体数最低,上游通天岩绿藻及甲藻总个体数最多,而下游碧落湖的蓝藻和硅藻的总个体数最多;(3)总氮、总磷、铅、钙、浮游动物Shannon-Weaver指数与浮游植物Shannon-Weaver指数从上游向下游增加,而锰与镍含量则成相反趋势。文中探讨了水中元素之间、元素与生物之间、浮游动植物之间的相互关系。本文对风景区水源的生态环境的研究风景区旅游资源开发与管理提供参考。 相似文献
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The general potential, exchange, and actual (pH) acidities were investigated in the litter of the succession row of swamp birch woods. Their variabilities constitute, respectively, 75.9–174.4, 3.7–25.8 mmol (+)/100 g of the sampling, 3.7–5.5. For the first time, using the methods of geostatistics, their spatial variability was analyzed and the contributions of the trend, autocorrelation component, and the radius of the spatial correlation were estimated. It was established that in combination with the woody plants detritus, which is uniformly distributed along the ecological profile, the specific composition of the grass-moss tier, which corresponds to the humidity of edaphon, forms the picture of the spatial structure of acid properties of the litter. It was noted that the prime cause of variability consists in the particularities of the water regime of the habitats of swamp birch woods. 相似文献
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基于构件理论,采用灰色关联度分析技术,对四川缙云山1989年风灾迹地林窗内大头茶(Gordoniaacumenata)幼苗种群构件结构及其与环境因子的关系进行了研究。结果表明,四川缙云山大头茶幼苗种群构件结构主要分为一级枝、二级枝、当年生枝、空间结构、叶片等几大部分,分别可以以一级枝数或茎粗或长度、二级枝数或基粗或长度、当年生枝数、3年生一级枝数、总叶数等的变化特征来表达其动态特点。前四者间的相关性亦很高,后者(包括主茎上叶面积)和主茎上第一一级枝离地面高、主茎上第一叶距地高为比较稳定的特征,受其它生态因子作用影响不十分显著。相对而言,土壤全N、全P、全K、有机质含量及其pH值是比较关键的环境因子;而海拔高度和林自大小及地形坡度却比较次要。灰色关联度分析不失为一种比较简捷而有效的分析植物种群构件结构特征间及与环境因子间关系的方法。关键词 相似文献
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研究沿用不可转移生态足迹反映旅游城镇化地区所承受的生态压力,利用偏最小二乘法构建足迹与驱动因子之间的回归模型,并通过构建驱动指数模型,比较各驱动因素对不可转移生态足迹变化的贡献。以张家界为案例地,研究旅游城镇化各阶段足迹演变及驱动规律。研究结果显示:(1)旅游城镇化地区不可转移生态足迹、人均不可转移生态足迹总体上呈现出平缓增长的动态变化,发展能力具有不稳定性。对外开放程度的提高,并不能抑制足迹的增长。在不控制生产总量的情况下,资源生产效率的提高会带来更多的不可转移足迹。(2)各因素对人均不可转移生态足迹影响的弹性系数由大到小分别为城镇居民人均可支配收入、第二产业增加值、城镇化率、第三产业增加值、资源生产效率、城市建设用地、第一产业增加值、旅游人口密度。产业内部结构会影响产业增加值对人均不可转移足迹的弹性系数。(3)旅游城镇化初级阶段,不可转移生态足迹增加,最主要的驱动因素是第二产业增加值、旅游人口密度、第三产业增加值;旅游城镇化高级阶段,不可转移生态足迹增加,最主要的驱动因素是第三产业增加值、第二产业增加值、第一产业增加值。建议如下:在旅游城镇发展的初级阶段,合理推进城镇化进程,控制旅... 相似文献
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国家大型煤电基地生态环境监测技术体系研究——以内蒙古锡林郭勒盟煤电基地为例 总被引:2,自引:0,他引:2
随着我国煤电基地建设进程的不断加快,煤电基地建设与开发活动引起的环境问题也日趋严重。了解生态环境质量现状,评估其对生态系统与人民健康水平的影响,制定合理的保护、治理、恢复策略是煤电基地环境保护工作的重中之重,而生态环境监测是解决上述问题的基础。然而,现有的监测技术体系普遍存在自动化水平较低、成本较高、时空覆盖面较低等问题。鉴于物联网技术在提高信息采集效率和改善信息获取方式方面的作用日益显著,所以将物联网技术应用于煤电基地生态环境监测,从感知层、传输层、支撑层、应用层、用户层的角度明确生态环境监测技术体系,为解决上述问题提供有效途径。 相似文献
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Pilet C 《Comptes rendus biologies》2012,335(5):350-355
The creation of the Veterinary Schools in the 18th century would reveal a plethora of scientists, some of whom would be the precursors of Pasteur, some rivals, others followers collaborators or friends of the Master. Among the precursors let us name Chabbert, Huzard, Girard, Delafond, Renault, Toussaint, Galtier ; among the rivals: Chauveau, Arloing, Cornevin and Thomas; among the followers, collaborators or friends of Pasteur: Bouley, at first a resolute spontaneist, then the most fervent in defense of Pasteur (President of the Academy of Medicine and of the Academy of Sciences) and Nocard, Director of the School in Alfort, an important collaborator of Pasteur. Later, there was Leclainche, who created the International Office of Epizootics, and who was President of the Academy of Sciences; Guérin, who with Calmette developed the BCG vaccination; Ramon, the father of anatoxins (vaccines against diphtheria, and tetanus, combined vaccines, adjuvants to immunity). Thus, the creation of the Veterinary Schools contributed not only to the evolution of the notion of contagion, to the amelioration of animal health and the economics of agricultural production, but also to serious advances in human care, and to the protection of public health. 相似文献
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赤松毛虫越冬幼虫生化物质变化与抗寒性的关系 总被引:12,自引:2,他引:12
昆虫的抗寒性与其体内生化物质的种类、含量密切相关。测定了赤松毛虫(Dendrolimusspectabilis)越冬幼虫体内和血淋巴内抗寒物质含量的变化,结果表明,血淋巴内小分子碳水化合物总量1月份为10月份的3.8倍,其中以葡萄糖、海藻糖和山梨醇增加幅度较大,依次为10月份的10.08倍、2.84倍、7.44倍。3月份有较大幅度的下降,虫体内糖原含量下降了56.5%。越冬期苏氨酸、丝氨酸、谷氨酸、丙氨酸、胱氨酸增加幅度较大,分别比越冬前增加了493.8%、433.7%、474.2%、21.5%和47.1%,甘氨酸、天门冬氨酸、蛋氨酸、亮氨酸、酪氨酸、苯丙氨酸、组氨酸、精氨酸、脯氨酸含量则有较大幅度的降低。越冬幼虫体内脂肪含量下降,蛋白质含量上升。应用蛋白质垂直平板电泳法对糖蛋白进行电泳分析发现糖蛋白含量增加,为越冬前的300%。综合分析认为赤松毛虫越冬幼虫体内抗寒物质系统为小分子碳水化合物类(山梨醇、海藻糖、葡萄糖)-糖蛋白-氨基酸类(丙氨酸、苏氨酸、谷氨酸等)。该系统可随生态条件的改变而变化。 相似文献
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基于生态系统服务视角的山水林田湖草生态保护与修复——以洞庭湖流域为例 总被引:2,自引:0,他引:2
山水林田湖草系统保护与修复的重要目标是维护和提升区域生态系统服务。基于山水林田湖草生命共同体理念,以维护和提升人类福祉所需的重要生态系统服务为目标,提出生态系统服务视角下的山水林田湖草系统治理框架,以实现流域生态系统整体保护、质量提升和格局优化。基于该框架,以洞庭湖流域为例,通过流域生态系统格局、生态系统质量状况分析、流域生态系统服务重要性评估和生态问题识别,构建流域生态安全格局,为实现可持续的山水林田湖草生命共同体提出系统保护与修复布局建议。通过洞庭湖流域的分析案例为流域山水林田湖草生态保护与修复重要区域的识别提供了可借鉴的指标和定量分析方法,为流域尺度构建生态安全格局、实现山水林田湖草系统保护和修复提供思路和途径。 相似文献
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This study had the purpose to compare with development of fitness, motor ability and health among various living environments of the sea-side, the urban, and the mountain districts, where were situated at Nadachi town on the suburbs of Niigata Prefecture. Five hundred thirty-five children (aged 4-15 yrs) were measured at the kindergarten, the fundamental school, and the junior high school. Measuring items of the physique were the height, the weight, the chest circumference, the sitting height, and the foot area. Physical fitness tests were the muscular grip-strength, the lung vital capacity, the closed-eye single-leg balance, the dipping time of the upper extremity, the vertical jump, the standing trunk flexibility, the endurance run, and pull-up. And, motor ability tests were the finger tapping, 5m shuttle run, 50m dash, and the ball throwing. As items of health inspection, the blood pressure (systolic and diasystolic) and the visual ability were adopted. As results of this study, following data were obtained; 1) At the sea-side environment, development of the muscle power, the respiratory function, and the physique were showed much faster rate of growth at the childhood than that of the other ones, significantly (P less than 0.01). 2) At the mountain environment, the arch-bend of the foot print only were appeared larger areas than that of the other ones, significantly (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Tohno Y Tohno S Mahakkanukrauh P Azuma C Vaidhayakarn P Moriwake Y Ohnishi Y Minami T 《Biological trace element research》2003,91(3):217-230
To elucidate quantitative changes of Ca, P, and Mg in the arteries with aging, the authors investigated changes of the mass
ratios of Mg to Ca and P in the arteries of Japanese and Thai by inductively coupled plasma-atomic emission spectrometry.
The arteries of Japanese that were used were the thoracic and abdominal aortas, coronary, common iliac, internal iliac, external
iliac, and femoral arteries, in which very high accumulations of Ca and P occurred in old age. The arteries of Thai that were
used were the abdominal aorta, ramifying site of the abdominal aorta, coronary, common iliac, internal iliac, and external
iliac arteries.
It was found that there were extremely significant correlations both between Ca and Mg contents and between P and Mg contents
in all of the arteries of the Japanese and the Thai. With regard to the mass ratio, the mass ratios of Mg to Ca ranged from
1.5% to 2.1% in the six arteries of the Japanese, except for the thoracic aorta at 3.1%, at an advanced stage of atherosclerosis,
being similar to each other. In the arteries of the Thai, the mass ratios of Mg to Ca ranged from 1.9% to 3.0%, except for
the coronary artery at 0.5%, at an advanced stage of atherosclerosis.
The mass ratios of Mg to P ranged from 2.5% to 2.7% in the six arteries of the Japanese, except for the coronary artery at
1.8%, at an advanced stage of atherosclerosis. With regard to the arteries of the Thai, the mass ratios of Mg to P ranged
from 1.9% to 3.3%, except for the coronary artery at 0.7%, at an advanced stage of atherosclerosis. These results revealed
that both the mass ratios of Mg to Ca and Mg to P were almost similar among the arteries of Japanese and Thai, except for
the coronary arteries. Therefore, these results suggested that the inorganic deposits in the coronary arteries of Japanese
and Thai were similar to those in the intimal tunica of the thoracic aorta, whereas in the other arteries, they were similar
to those in the middle tunica of the thoracic aorta. 相似文献
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结合国家级生态文明先行示范区生态文明建设的基本要求,将欧洲环境局的DPSIR环境管理模型引入到其生态文明建设分析评价当中,阐述了其分析评价的四个核心要点,并据此从生态制度、生态经济、生态社会和生态环境4个方面选取40个指标建立了评价指标体系,以湘江源头国家级生态文明先行示范区为研究对象,运用粗糙集理论和方法,就其生态文明建设展开分析评价,验证了评价模型的合理性、可操作性。结果表明:一是DPSIR模型能够很好地体现生态文明建设各因素间的因果关系信息,模型显示,可通过增强"驱动力"、降低"压力"、优化"状态"、妥对"影响"、全面"响应"等途径来增强示范区生态文明建设效果。二是从指标权重和研究的结果来看,对生态文明建设有着正向影响且权重较大的指标,要重视其正向影响并积极推动其效应最大化,对一些制约或影响生态文明建设的负向指标,要严格做好控制工作并减少其影响效应。三是研究得出湘江源头国家级生态文明先行示范区宁远、江华和蓝山三县生态文明建设总体水平呈现稳步上升的趋势。生态社会、经济和制度的"驱动力"持续增强,生态资源和环境"状态"不断改善,生态社会和经济"影响"逐渐合妥,生态社会、经济和环境"响应"全面迅速,但经济转型、资源和环境"压力"仍然亟待降低。建议从生态文明先行示范区创建的要求着手,对照目标,弥补差距,推动示范区建设高质量发展。 相似文献
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基于构件理论,采用灰色关联度分析技术,对四川缙云山1989年风灾迹地林窗内大头茶(Gordonia acumenata)幼苗种群构件结构及其与环境因子的关系进行了研究。结果表明,四川缙云山大头茶幼苗种群构件结构主要分为一级枝、二级枝、当年生枝、空间结构、叶片等几大部分。分别可以以一级枝数或茎粗或长度、二级枝数或茎粗或长度、当年生枝数、3年生一级枝数、总叶数等的变化特征来表达其动态特点。前四者间的相关性亦很高,后者(包括主茎上叶面积)和主茎上第一级枝离地面高、主茎上第一叶距地高为比较稳定的特征,受其它生态因子作用影响不十分显著。相对而言,土壤全N、全P、全K、有机质含量及其pH值是比较关键的环境因子;而海拔高度和林窗大小及地形坡度却比较次要。灰色关联度分析不失为一种比较简捷而有效的分析植物种群构件结构特征间及与环境因子间关系的方法。 相似文献
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The interactions between the substrates of the 2E1 isoform of the human cytochrome P450 and receptor were simulated. It was found that the CP4 isoform of the cytochrome of the bacterial cell is highly homologous to the 2E1 isoform of the human cytochrome P450. The orientation of the substrates of the 2E1 isoform in the CP4 isoform of the bacterial cell cytochrome was performed. A cavity in the receptor was found that is responsible for the binding of the substrate. Amino acid residues Phe87, Pro89, Val119, Thr185, Leu244, Leu245, Leu246, Val247, Gly248, Gly249, Thr252, Val295, Asp297, Cys357, Ile395, and Val396, the heme, and water molecules are involved in the formation of the cavity. The mode of the interactions of the substrate molecule with cytochrome was analyzed. Active sites of the receptor, and a part of the substrate molecule responsible for the binding to cytochrome were found. Equations for the dependence of the Michaelis constant on the structural parameters of complexes of substrates with cytochrome were derived. 相似文献
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根据床板珊瑚形珊瑚的系统分类特点,自动鉴定程序从高级分类单位开始,逐步向较低级别进行,直至将标本鉴定到种。在仔细分析研究属以上级别分类单位鉴定特征性质的基础上,首次提出了归属度的概念,通过归属度计算判定被鉴定标本的归属;在对每一属的各个种进行数值分类的基础上,利用相似性系数对被鉴定标本进行统计识别,将标本鉴定到种。 相似文献
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C. J. Tsai S. Kumar B. Ma R. Nussinov 《Protein science : a publication of the Protein Society》1999,8(6):1181-1190
Folding funnels have been the focus of considerable attention during the last few years. These have mostly been discussed in the general context of the theory of protein folding. Here we extend the utility of the concept of folding funnels, relating them to biological mechanisms and function. In particular, here we describe the shape of the funnels in light of protein synthesis and folding; flexibility, conformational diversity, and binding mechanisms; and the associated binding funnels, illustrating the multiple routes and the range of complexed conformers. Specifically, the walls of the folding funnels, their crevices, and bumps are related to the complexity of protein folding, and hence to sequential vs. nonsequential folding. Whereas the former is more frequently observed in eukaryotic proteins, where the rate of protein synthesis is slower, the latter is more frequent in prokaryotes, with faster translation rates. The bottoms of the funnels reflect the extent of the flexibility of the proteins. Rugged floors imply a range of conformational isomers, which may be close on the energy landscape. Rather than undergoing an induced fit binding mechanism, the conformational ensembles around the rugged bottoms argue that the conformers, which are most complementary to the ligand, will bind to it with the equilibrium shifting in their favor. Furthermore, depending on the extent of the ruggedness, or of the smoothness with only a few minima, we may infer nonspecific, broad range vs. specific binding. In particular, folding and binding are similar processes, with similar underlying principles. Hence, the shape of the folding funnel of the monomer enables making reasonable guesses regarding the shape of the corresponding binding funnel. Proteins having a broad range of binding, such as proteolytic enzymes or relatively nonspecific endonucleases, may be expected to have not only rugged floors in their folding funnels, but their binding funnels will also behave similarly, with a range of complexed conformations. Hence, knowledge of the shape of the folding funnels is biologically very useful. The converse also holds: If kinetic and thermodynamic data are available, hints regarding the role of the protein and its binding selectivity may be obtained. Thus, the utility of the concept of the funnel carries over to the origin of the protein and to its function. 相似文献
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Animals and products derived from different organs of their bodies have constituted part of the inventory of medicinal substances used in various cultures since ancient times. The article reviews the history of healing with animals in the Levant (The Land of Israel and parts of present-day Syria, Lebanon, and Jordan, defined by the Muslims in the Middle Ages as Bilad al-Sham) in the medieval and early Ottoman periods. Intensive research into the phenomenon of zootherapy in the medieval and early Ottoman Levant has yielded forty-eight substances of animal origin that were used medicinally. The vast majority of these substances were local and relatively easy to obtain. Most of the substances were domestic (honey, wax, silkworm, etc.), others were part of the local wildlife (adder, cuttle fish, flycatcher, firefly, frog, triton, scorpion, etc.), part of the usual medieval household (milk, egg, cheese, lamb, etc.), or parasites (louse, mouse, stinkbug, etc.). Fewer substances were not local but exotic, and therefore rare and expensive (beaver testicles, musk oil, coral, ambergris, etc.). The range of symptoms that the substances of animal origin were used to treat was extensive and included most of the known diseases and maladies of that era: mainly hemorrhoids, burns, impotence, wounds, and skin, eye, and stomach diseases. Changes in the moral outlook of modern societies caused the use of several substances of animal origin to cease in the course of history. These include mummy, silkworm, stinkbug, scarabees, snail, scorpion, and triton. 相似文献
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试谈禾本科植物生殖器官主要性状的分类价值及其适用等级 总被引:2,自引:0,他引:2
生殖器官性状一直是禾本科植物分类的主要依据,但由于各个性状所附实体的形态特点、着生位置、发育程度和环境饰变的差异,其分类价值是不尽相同的。为了克服该类性状使用上的种种弊病,本文特对主要宏观性状的分类价值进行了评述,总结了它们在应用中各自适宜的等级范围。其中象花序的类型、小穗的着生、小花和果实的形状等价值较高,通常适合于族级以上类群的划分;花序的形状、小穗的排列、果实的类型等价值偏低,通常适合于属、种级类群的区分;而花序的长短与粗细、小穗轴、内稃等价值较低,通常适合于种级或种级之下类群的鉴分。 相似文献