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1.
2007年9月-2008年9月,采用诱捕法采集粪金龟子,以不同水土治理措施植被、耕作农田和天然草地为研究样地,分析了内蒙古皇甫川流域不同土地管理方式对粪金龟子群落的影响.共捕获粪金龟子6169头,隶属于2科5属15种,优势种为直蜉金龟和小驼嗡蜣螂,分别占总捕获量的66.54%和13.26%.缺少适宜林地环境生存的种类是研究地区粪金龟子群落的基本特征.与耕作农田和天然草地相比,几种水土治理措施均未导致粪金龟子群落多度、生物量和物种丰度显著提高.粪金龟子群落生物量和物种丰度以及功能群Ⅱ和Ⅲ的多度与树(草)高呈显著负相关.受长期农业耕作以及缺少大型食草动物的影响,皇甫川流域的粪金龟子群落组成以功能群Ⅱ和Ⅲ为主,功能群Ⅰ的多度和物种丰度较低.研究地区居民点的人畜粪便为粪金龟子提供了充足的食物,导致附近耕作农田中的粪金龟子群落具有较高的多度和丰度.天然草地是该流域粪金龟子群落的适宜生境.在区域尺度推广水土流失综合治理成功经验的同时,保护天然草地和饲养适当数量家畜(特别是大型食草牲畜)是维护粪金龟子群落多样性和生态系统功能的有效措施.  相似文献   

2.
2008年6月-2009年9月,在内蒙古典型草原放牧区,分析了马、牛和羊鲜粪中粪金龟子的物种多样性、群落结构、功能群和取食偏好.共捕获粪金龟子7805头,隶属于3科4属32种,优势种为符号蜉金龟(Aphodius comma)、游荡蜉金龟(Aphodius erraticus)和泥蜉金龟(aphodius sordec...  相似文献   

3.
【目的】为研究内蒙古典型草原粪食性金龟对放牧牲畜粪的取食偏好和日活动节律特征。【方法】2010年6、8和10月,以3种放牧牲畜(牛、马和羊)鲜粪块为诱饵,采用诱捕法采集粪食性金龟。【结果】内蒙古典型草原粪食性金龟显示对3种放牧牲畜(牛、马和羊)粪块的多食性特征,但不同功能群或不同物种显示不同取食偏好以及不同的日活动节律特征。中型掘洞型粪食性金龟(如小驼嗡蜣螂Onthophagus gibbulus、黑缘嗡蜣螂O.marginalis nigrimargo和游荡蜉金龟Aphodius erraticus)显示对牛粪的取食偏好、以及昼行性行为特征;中型和小型粪居型粪食性金龟(如马粪蜉金龟A.subterraneus、泥蜉金龟A.sordescens和符号蜉金龟A.comma等)则偏好取食马粪,小型粪居型粪食性金龟(如符号蜉金龟)有全天活动的行为特征。【结论】在内蒙古典型草原粪食性金龟取食偏好和日活动节律的形成和进化中,体型和行为特征是主要内因,牲畜粪块的外形和理化性质、以及季节更替中的气温变化是重要外因。  相似文献   

4.
内蒙古中部地区土壤金龟子群落特征   总被引:3,自引:2,他引:1  
刘新民 《生态学杂志》2008,27(7):1161-1166
2003-2004年,采用土壤样方法和粪诱捕法调查了内蒙古中部地区7个不同生境中的土壤金龟子群落特征,并以群落系数、欧氏距离、百分率相似系数和因子分析等方法对不同土壤金龟子群落之间的相似性进行了分析.共计捕获土壤金龟子101 788头,分属于7科22属59种.其中,植食性种类3科12属18种,主要为鳃金龟科和丽金龟科的种类;粪食腐食性种类4科10属41种,主要为金龟科、蜉金龟科和粪金龟科的种类.对几种群落相似性聚类分析方法所得结果的对比表明,因子分析方法所得的结果是较为合理的,因子分析排序的结果将7个土壤金龟子群落分为2类:一类为典型草原、草甸草原、荒漠草原和沙地;另一类为农田、退耕地和人工林地.  相似文献   

5.
2007年4-10月,采用野外和室内实验相结合的方法,研究了荒漠草原马粪中的粪金龟子群落组成和对马粪分解的影响.共捕获粪金龟子13528头,隶属于3科4属26种,优势种为符号蜉金龟(Aphodius comma),占总捕获量的88.5%,不同季节粪金龟子群落组成明显不同;在鲜马粪中活动的粪金龟子以粪居型蜉金龟为主,在鲜马粪堆置3d时种数和个体数达到最高,6d后全部离开;马粪经过136 d分解,残留率为52.5%,残留粪样中氮和磷释放较慢,钾释放较快;结合室内分解实验的结果,认为粪金龟子主要通过在马粪中活动对其分解产生影响,并与风蚀作用成为荒漠草原马粪块破碎的重要动因,主要发生在春季和秋季.  相似文献   

6.
北方草地牛粪中金龟子的多样性   总被引:1,自引:0,他引:1  
2006年5—9月,在内蒙古鄂温克族自治旗(典型草原)、内蒙古科尔沁左翼后旗(沙地草原)和吉林省长岭县(草甸草原)3种放牧草地中,采用陷阱法和野外牛粪解剖手捡法采集牛粪中的金龟子,共采集金龟子75981头,分属9科43种。对其进行多样性分析,结果表明:长岭和鄂温克族自治旗牛粪生境中的优势种均是黄缘蜉金龟Aphodius sublimbatus(Motschulsky)(分别占各自生境捕获个体数的88.188%和93.547%),科尔沁左翼后旗的优势种为双顶嗡蜣螂Onthophagus bivertex Heyden(67.067%)、小蜉金龟Aphodius pusillus(Herbst)(14.524%)和独角凯蜣螂Caccobius unicornis(Fabricius)(10.264%)。科尔沁左翼后旗牛粪中金龟子的Simpson指数、Shannon-Wiener指数和均匀度指数在3种草地中均最高,长岭次之,鄂温克族自治旗最低。3种草地牛粪中金龟子的物种数与其丰富度相一致:长岭>科尔沁左翼后旗>鄂温克族自治旗。Sorenson群落相似性系数在0.458—0.578之间。  相似文献   

7.
刘新民 《昆虫学报》2011,54(12):1406-1415
为阐明放牧对粪金龟子群落的影响,于2004年5-9月,选择内蒙古典型草原不同放牧强度(无放牧、适度放牧和过度放牧)草地为样地,采用诱捕法采集粪金龟子标本,分析了放牧对粪金龟子群落的影响.结果表明:共捕获粪金龟子60 839头,隶属于3科5属24种.放牧影响下,粪金龟子群落个体数、种数和生物量均发生显著变化,不同粪金龟子...  相似文献   

8.
长期重度放牧通过加剧水氮限制减少植物多样性与生态系统功能。相反,缺乏放牧干扰(生物量移除)会通过增加光竞争减少物种多样性,从而弱化生态系统稳定性,而这一过程会由于资源富集而加剧。因此,如何维持物种多样性和群落稳定性仍然是世界草原可持续管理的一大挑战。在本研究中,我们在中国内蒙古3个放牧强度的长期实验样地设置了为期4年的控制实验,来探究结合资源添加与生物量移除(同时增加水、氮和光的有效性)对物种丰富度与群落稳定性的影响。研究结果表明,在4年资源添加结合生物量移除处理下,群落初级 生产力增加,同时物种丰富度与群落稳定性能够维持。在物种与功能群水平上,地上生产力能够保持时间稳定性。物种丰富度维持的主要 原因是:在资源富集的情况下,生物量移除能够增加光的有效性。物种异步性与功能群稳定性有助于群落稳定性维持。我们的研究结果表 明,资源添加与生物量移除结合的管理方式,不仅能够增加草地初级生产力,而且能维持其物种多样性、异步性与群落稳定性。在世界范 围内,长期放牧导致的草原退化与资源富集引起的其生物多样性丧失仍将是人类面临的主要生态问题,我们的研究结果对于半干旱草原以 及其它草原的适应性管理具有重要的意义。  相似文献   

9.
保护性耕作和杂草多样性是现代生态农业关注的热点问题.尽管保护性耕作下农田杂草多样性有所提高,但耕作方式与养分管理方式对农田杂草群落多样性的交互影响尚未探明.本研究以山东省济南市一块连续3年施行不同耕作方式(免耕、深松、旋耕、深耕)和不同养分管理措施(农户常规:年施氮肥480 kg·hm-2,高产高效:年施氮肥360 kg·hm-2,优化管理:年施氮肥300 kg·hm-2)的冬小麦-夏玉米轮作农田为研究样地,调查并比较了不同管理模式下农田春季杂草群落特征.结果表明: 该冬小麦-夏玉米农田春季杂草群落共发现杂草15种,其中优势物种为马唐和稗;与深耕和旋耕相比,免耕和深松下杂草密度较高.在群落多样性方面,深耕处理下的物种丰富度和均匀度最低,而群落优势度高于其余3种耕作方式;在养分管理中,随着施肥量的增加,物种丰富度和均匀度均升高;深耕和旋耕处理下,随着施肥量的增加,群落优势度升高;而在免耕深松处理下,群落优势度会随着施肥量的增加而减少.在杂草群落生物量方面,免耕和深松的生物量显著高于深耕和旋耕,农户常规处理均高于其余两种养分管理方式,杂草生物量最高的组合是免耕+农户常规.免耕和施肥将提高农田春季杂草群落丰富度、均匀度和生产力.  相似文献   

10.
基于3龄幼虫首次描述了中国5种蜉金龟幼虫的形态特征,分别是:方胸蜉金龟 Aphodius quadratus Reiche、黄缘蜉金龟 A.sublimbatus Motschulsky、直蜉金龟 A.rectus Motschulsky、游荡蜉金龟 A.erraticus(Linnaeus)(补充描记).文中列出了中国蜉金龟幼虫的分种检索表.主要鉴别特征是:头部、内唇和臀节等.  相似文献   

11.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
14.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

15.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

16.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

17.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

18.
《Ibis》1894,36(3):447-460
  相似文献   

19.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

20.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

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