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1.
2004年8—9月在若尔盖湿地国家自然保护区采用样方法对高原林蛙(Ranakukunoris)、倭蛙(Nanoranapleskei)和岷山蟾蜍(Bufominshanicus)的生境选择性进行了研究。先设置16个50m×50m的样地,再在每个样地内分25个10m×10m的样方,测量每个样方中的12个生境因子(牧场性质、草本高度、草本盖度、牛粪数量、鼠兔洞口数量、鼢鼠土堆数量、地表温度、地表湿度、土壤温度、离小型水体距离、离大型水体距离、离道路距离)。结果表明:这3种两栖类均偏好离溪流、水塘等小型水体距离较近(≤100m)、离河流、湖泊等大型水体距离较远(>1000m)、适度放牧(牛粪数量1~20)以及无鼠兔(Ochotonasp·)洞口的生境。通过比较,发现高原林蛙和倭蛙显著选择夏牧场、草本高度5·1~10·0cm、离小型水体0~50m的生境,显著不选择鼢鼠土堆太多(>10)的生境;岷山蟾蜍对牧场性质、离道路距离无显著选择性,显著选择草本高度>20·0cm、离小型水体51~100m的生境,不选择无鼢鼠土堆的生境;高原林蛙显著选择离道路>50m的生境;倭蛙显著选择离道路0~50m的生境。3种两栖类在生境选择上产生了一定的分离,表明各自有着特殊的生境需求。判别分析表明,牧场性质、草本高度、地表湿度、土壤温度、鼢鼠土堆数量、离大或小型水体距离、离道路距离是区别3种两栖类生境选择的重要参数。  相似文献   

2.
道路交通是社会和经济发展的枢纽,了解道路如何影响野生动物种群的连通性是道路生态学的挑战之一。小型哺乳动物作为检验环境影响的指示物种,对维持生态系统健康有重要作用。2020年7月10—17日,调查了新疆卡拉麦里山有蹄类野生动物自然保护区内国道216、县级道路和沙石道路3种不同类型道路对大沙鼠Rhombomys opimus分布(洞穴数量、洞群数量和洞群面积)的影响。研究发现,保护区内3种道路对大沙鼠分布的影响从大到小依次为国道216、县级道路和沙石道路。3种道路主要影响大沙鼠的洞群数量和洞群面积。洞群数量的峰值出现在国道216两侧800 m,远高于县级道路的100 m和沙石道路的10 m。国道216和县级道路两侧洞群面积峰值出现在800 m,洞群面积并未随距沙石道路距离而改变。路面基质而非车流量可能是3种道路对大沙鼠影响显著不同的主要原因。本研究可为保护区内道路管理提供重要的科学指导。  相似文献   

3.
风力发电作为绿色新能源在近年来快速发展的同时,其对周边环境的影响尤其是对鸟类的影响成为研究的热点。为探究鸟类对风电场风机的响应,2019年1、3、4、5月,采用样线法对广东省连州风电场的鸟类多样性进行了4次调查。共设置样线32条,根据样线离风机的距离分为4个梯度,其中,100~300 m样线6条,300~500 m 13条,500~700 m 8条,700 m 5条。结果显示:1)共记录鸟类112种,隶属于12目37科,目、科数量最多的分别为雀形目Passeriformes(78种)、画眉科Timaliidae(12种);2)鸟类物种、属和科的丰富度随着离风机距离的增加而呈增加趋势:在500 m以内无显著性差异,500 m外显著增加;种-属比率也呈现出相似的增加趋势。本研究结果表明,风力发电机对鸟类的影响主要在距离500 m的范围,这种影响可能与风机产生的噪音、直接或间接的栖息地改变等有关。  相似文献   

4.
风电作为清洁可再生绿色能源越来越受到世界各国的重视,其建设规模也在不断扩大,导致风电建设与鸟类保护的矛盾进一步凸显,如何协调风电发展与物种保护已成为生态学家和保护生物学家关注的热点主题。为了探究风机对鸟类物种、功能和谱系的影响,本研究于2019年1、3、4、5月,采用样线法对连山风电场的鸟类多样性进行了4次调查。根据样线离风机距离的远近设置4个梯度: 100~300 m有6条样线,300~500 m 有13条样线,500~700 m 有8条样线,>700 m 有5条样线。结果表明: 本次调查中记录了繁殖留鸟76种,隶属于11目31科,目、科中数量最多是雀形目(53种)和画眉科(12种)。鸟类物种丰富度、功能丰富度(FRic)和谱系多样性(Faith PD)随着离风机距离的增加呈增加趋势: 在500 m以内未显著增加,500 m外呈显著增加趋势;鸟类群落水平的扩散能力呈现出增加趋势。鸟类群落的平均成对功能和谱系距离的标准化效应值(SES.MFD和SES.MPD)均小于0,其中显著低于随机值的样线占比约为50%(P<0.05)。风力发电机对鸟类物种、功能和谱系的影响主要在前500 m的距离;本研究的4个梯度中,鸟类群落的功能和谱系结构均表现为聚集特征。研究证实,风机对鸟类的影响是多维度的,在评估风机对鸟类群落的影响时仅考虑物种多样性可能难以提供全面的信息。  相似文献   

5.
祁连山东段高原鼢鼠对高寒草甸危害评价   总被引:1,自引:0,他引:1  
周延山  花立民  楚彬  刘丽  姬程鹏  田永亮 《生态学报》2016,36(18):5922-5930
为了客观评价高原鼢鼠(Myospalax baileyi)对高寒草甸的危害程度,在祁连山东段研究了高原鼢鼠不同种群密度与草地质量之间的关系,共设置了3个高原鼢鼠种群密度梯度,调查了3个危害等级变量(鼠丘数、鼠丘面积和鼠丘产草量)和6个生境变量(草地产草量、总盖度、可食牧草产量、植被组成、土壤水分和土壤紧实度),通过One-Way ANOVA检验法研究这些因子与高原鼢鼠危害程度的关系。结果表明:在设置的3个种群密度梯度下,草地产草量、总盖度、可食牧草产量和鼠丘产草量无显著性差异;草地植物群落结构、新鼠丘面积占调查区面积的比例无显著性差异,除高原鼢鼠采食深度(0—20 cm)外,3个种群密度区土壤紧实度无显著性差异,而0—30 cm处土壤水分存在显著性差异,说明本研究中不同高原鼢鼠种群密度区的草地质量没有显著性差异。此外,研究结果表明调查样地大小与危害评价有着密切关系,在高寒草甸区,单个样方调查面积以0.5 hm~2以上为宜。  相似文献   

6.
野猪是非洲猪瘟(ASF)传播的重要媒介,神农架林区野猪种群数量高、分布广,调查野猪分布对ASF防控有着重要意义。本研究首先通过布设红外相机117台、样线287条调查神农架林区野猪实体和痕迹位点后,应用最大熵模型预测林区野猪分布,再根据野猪、居民区、交通要道的空间分布数据,应用核密度估计法分析神农架林区各地野猪传播ASF的风险。调查发现野猪实体及其粪便、足迹链、巢穴等共2070处,遍布神农架林区全境,预估野猪数量为18424头;林区松柏镇、阳日镇、新华镇、省道S307和国道G209沿线等野猪密度高、人口集中的地区为野猪传播ASF极高风险区;极高风险区约4km外的地区为高风险区;其他地区为中低风险区。本研究表明,松柏镇、阳日镇、新华镇、省道S307、国道G209及周围地区是ASF疫情防控工作中的重点区域,应在这些重点区域做好主动监测防控工作,实时监测ASF动态变化。  相似文献   

7.
腾格里沙漠东南缘公路对路域植被物种组成的影响   总被引:1,自引:0,他引:1  
Feng L  Li XR  Guo Q  Zhang JG  Zhang ZS 《应用生态学报》2011,22(5):1114-1120
沿腾格里沙漠东南缘省道201线沙坡头-景泰段2侧设置48条垂直于公路的样线,调查距路缘不同距离处植被的物种分布特征,研究干旱荒漠区公路建设和运营对植被物种组成的影响.结果表明:随着距路缘距离的增加,草本植物的种数、盖度、生物量和α多样性均逐渐减小,5 m后与对照差异不显著,高度在0~6 m处较大,密度变化不显著.0~2 m处草本植物的物种周转速率较低,2~5 m处最高,10 m后物种组成与对照相似.路缘处的草本植物群落以禾本科植物占优势,抗干扰能力较强的白草、虎尾草和冰草占草本植物总个体数的68.6%.其中,虎尾草在距路缘1 m后,白草和冰草在距路缘2 m后数量和频度迅速减小,而菊科植物茵陈蒿和冷蒿急剧增加,距路缘2 m后占草本植物总个体数的70%.路缘处灌木植物的盖度和密度显著小于对照,物种组成与对照没有显著差异.  相似文献   

8.
鸟击对民用和军用飞机的飞行安全构成严重威胁,了解和掌握机场及其周边地区的鸟类群落结构对机场开展鸟击防范工作具有重要意义。本研究于2013年6月至2014年5月,采用固定距离样线法对重庆江北机场以机场中心为圆心、半径8 km范围内的区域进行鸟类多样性调查。共记录鸟类102种,隶属于15目、40科。其中留鸟44种,夏候鸟30种,冬候鸟13种,旅鸟15种;雀形目鸟类占绝对优势,计54种,占调查鸟类物种总数的52.94%。对鸟类群落结构分析结果表明,冬季密度最大,夏季最低;秋季的多样性指数最高,夏季最低;春季的均匀度指数最高,夏季最低;夏季的优势度指数最高,秋季最低。结合鸟类的密度D值、分布系数ADC值、鸟击风险值R、相对风险比例RE以及鸟类生活习性等综合分析,与鸟击发生关系密切的鸟种为家燕(Hirundo rustica)、灰椋鸟(Sturnus cineraceus)、八哥(Acridotheres cristatellus)、黑卷尾(Dicrurus macrocercus)、金翅(Carduelis spinus)、珠颈斑鸠(Phasianus colchicus)以及人工饲养物种家鸽(Columba domestica)等,根据调查结果对重庆江北机场的鸟击防范工作提出了综合防治建议。  相似文献   

9.
2011年至2013年每年的5—8月,采用样线法对黑龙江呼兰河口湿地自然保护区夏季鸟类的群落组成与结构进行了研究。野外调查共记录鸟类13目33科91种,其中国家重点保护鸟类11种。区内夏季鸟类以非雀形目鸟类居多,共有18科53种,占总种数的58%;雀形目鸟类15科38种,占总种数的42%。从居留型来看,保护区夏季鸟类群落中留鸟16种,夏候鸟75种。在地理区系构成上,保护区以古北界物种为主,共有47种,占总种数的51.6%,其次是广布种,共有41种,占45.1%,东洋界物种仅有3种。连续3年的多样性指数呈下降趋势,推测人为活动干扰增加与河口湿地公园建设可能是导致鸟类数量减少的最主要因素。  相似文献   

10.
分析道路交通对濒危有蹄类动物行为模式的影响,阐明其行为反馈与适应机制,对制定道路工程干扰下濒危物种的保护方案具有重要意义。2015年和2016年6-8月,调查了国道216线白昼运营对新疆卡拉麦里山有蹄类野生动物自然保护区鹅喉羚(Gazella subgutturosa)集群特征和警戒行为的影响。研究发现,国道216线的扰动导致鹅喉羚集群规模显著增加;随着距国道216线距离越近,鹅喉羚警戒行为投入时间越多,距离道路500m可能是国道216线对鹅喉羚集群和警戒行为影响的阈值。本研究结果表明,道路带来的人为干扰与捕食风险相似,迫使鹅喉羚调节其集群规模和警戒水平。未来应加强道路等交通工程影响下保护区内野生动物的行为反馈和适应机制研究,据此提出减缓措施,降低道路对野生动物的负面影响。  相似文献   

11.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

12.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

13.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

14.
15.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

16.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

17.
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.  相似文献   

18.
A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/antifungal against two or more species as compared to the uncomplexed Schiff-base ligands.  相似文献   

19.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

20.
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