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1.
采用查询资料和实地调查相结合的方法,收集中国特有种川榛(Corylus kweichowensis Hu)的地理分布资料以及各分布区的气象数据;利用Kira温暖指数、Kira寒冷指数、徐文铎湿度指数、Holdrige生物温度、Holdrige可能蒸散率和Holdrige可能蒸散量对川榛地理分布格局与气候水热指标的关系进行研究;并采用主成分分析法对影响川榛分布的气候水热指标进行了分析.结果表明:川榛分布于中国的15个省(自治区、直辖市),水平分布范围为东经102°06′~121°59′、北纬25°11′~37°38′,分布的最北端和最东端均位于山东省牟平县,最南端和最西端分别位于贵州省安龙县和四川省泸定县;垂直分布海拔为300~2500 m,集中分布海拔为500~1000 m,主要分布于秦岭、伏牛山、大别山和大巴山等山系.川榛分布区的年均温、Kira温暖指数、年降水量和Holdrige生物温度的最适范围分别为1124℃~1772℃、9153℃·月-1~14924℃·月-1、59638~160175 mm和1166℃~1754℃,Kira寒冷指数、徐文铎湿度指数、年空气相对湿度、Holdrige可能蒸散量和Holdrige可能蒸散率的均值分别为-673℃·月-1、911、7481%、86025 mm和089,其分布南界和北界的Kira温暖指数、Kira寒冷指数和年降水量的范围分别为6290℃·月-1~16910℃·月-1、-3990℃·月-1~-110℃·月-1和42550~205820 mm;按照Holdrige分类系统,川榛属于暖温带和亚热带湿润森林生命地带类型中的树种,生态适应性较广.主成分分析结果表明:限制川榛地理分布的气候水热条件由高到低依次为低温条件、高温条件、湿度条件,因此,园艺化栽培川榛时可首先考虑1月均温、Kira寒冷指数、极端低温、无霜期和年均温等因素.  相似文献   

2.
中国榛属植物种质资源分布格局及其适生区气候评价   总被引:2,自引:0,他引:2  
应用地理信息系统和统计学原理,研究中国榛属植物分布规律,评价适生区气候,分析气候因子对其分布的影响,并根据适生气候的相似性,探讨榛属植物种间关系。结果表明:国内榛属植物纬度分布范围在24°31'N~51°42'N,经度分布范围在85°55'E~132°12'E,主要分布区从东北—华北山区、秦岭和甘肃南部及河南—华中—西南呈斜带状分布,分布种数在华中地区达到最多;垂直分布自东至西随经度降低海拔逐渐升高,纬度对各种质分布海拔影响存在显著差异;年均气温和冷温是影响榛属植物分布的关键气候因子;榛属植物分布种数与各气候因子间的回归方程为:Y=11.883-0.051X1+0.131X2-0.003X4-0.004X5-0.001X6+0.051X8,根据分布区气候相似性进行聚类分析,将我国榛属植物分为3类:平榛和毛榛为一类,川榛、华榛、刺榛、绒苞榛和滇榛为一类,维西榛为一类。  相似文献   

3.
关于川榛分类地位的商榷及新变种   总被引:2,自引:0,他引:2  
梁维坚 《植物研究》1988,8(4):115-118
本文深入分析与比较了"川榛"与"榛"在分类性状上的明显区别, 并考虑到榛属种间的平衡, 特别是再结合对其生态习性与地理分布的分析结果, 提出"川榛"由多年沿用的变种地位"Corylus heterophylla Fisch.var.sutchuenensis Franch."上升为独, 立的种其拉丁学名按照国际植物命名法规的规定, 恢复使用"Corylus kweichowensis Hu"之名称。与此同时, 根据作者积年调查之发现, 在"川榛"种内发表了短柄川榛(Corylus kweichowensis var.brevipes W.J.Liang, var.nov, )新变种。  相似文献   

4.
海南龙血树野生资源分布及其与水热关系的分析   总被引:1,自引:0,他引:1  
在全面调查海南龙血树(Dracaena cambodiana)野生资源地理分布的基础上,用温度指数、湿度指数等气候指标分析了海南龙血树野生资源地理分布与气候因子间的关系。结果表明,海南龙血树野生资源在中国仅分布于海南岛西南部山区及南部沿海地区,水平分布于108°42′40.9″~110°27′36.8″E,18°14′27″~19°20′28.5″N,垂直分布范围为0~900 m,仅发现10个现存分布点;海南龙血树属于热带雨林、季雨林小乔木状植物,具有强耐旱、喜阳和喜钙等生态习性,其分布区的绝大部分水热因子是其分布的主要限制因子。主成分分析表明,影响海南龙血树地理分布的主要水热指标的排序为热量因子>降水因子>湿度因子。根据野生居群的生境特点,我们推测水分和光照强度可能是影响海南龙血树种子萌发率或幼苗成活率的重要因子。  相似文献   

5.
为明确云南猕猴桃属种质资源的遗传背景,进一步发掘利用和保护野生种质资源,本研究对滇东北、滇东、滇东南、滇南和滇西北等5个野生猕猴桃资源主要分布区域开展实地调查和收集,对果实进行形态学鉴定评价分析,采用高效液相色谱法对果实糖酸、VC含量进行测定分析,利用10对SSR引物对211份野生猕猴桃资源进行遗传多样性分析。结果表明:云南野外分布有中华猕猴桃、美味猕猴桃、京梨猕猴桃、紫果猕猴桃、贡山猕猴桃等多种猕猴桃属植物,表型性状丰富多样,其中滇东北昭通地区的野生资源类型分布最为丰富广泛。66份资源的总糖含量范围为0.08%~8.90%,其中含量0.08%~5%的资源占比为57.58%;45份资源的总酸含量范围为0.75%~2.90%,其中含量1%~2%的资源占比为71.11%;61份资源VC含量范围为4.74~523 mg/100 g,含量为0~100 mg/100 g的资源占比78.69%、含量为100~200 mg/100 g的资源占比19.67%、含量为200 mg/100 g以上的资源占比1.64%。所考察野生资源的果实总糖、总酸和VC含量存在明显差异和多样性。10对SSR引物共扩增出421条条带,其中多态性条带421条,多态性比率为100%,对211份种质材料的区分率达100%,平均有效等位基因数为1.077,Shannon′s信息指数为0.1246,从DNA层面印证了云南猕猴桃属种质资源具有丰富的遗传多样性,并筛选出6份具有较高开发利用价值的野生资源。本研究为加快云南猕猴桃属种质资源的研究利用提供参考。  相似文献   

6.
李平星  高晨真  罗艳华  郭辉  孙伟 《生态学报》2024,44(5):1808-1821
科学合理地开发生态资产、促进其价值转化,是发展生态经济、推动生态文明建设的重要举措,对于促进生态敏感地区人与自然和谐共生、保障高质量可持续发展具有现实意义。以青藏高原为研究区,基于土地利用类型及其质量,从资源实物和生态服务两个类别开展生态资产评估和空间分布研究,融合生态产品供给-需求理论评价生态资产价值化潜力,进而解析生态资产及其价值化潜力的空间匹配关系,提出促进生态资产价值化的科学建议。结果表明:青藏高原生态资产类型多样,空间集聚特征明显,生态资产综合指数热点区主要分布在中部的羌塘、青南和川西藏东等地区,冷点区则分布在南部的山地灌丛及周边地区;生态服务类资产指数与生态资产综合指数呈现类似的空间分布格局,资源实物类资产指数的格局随地形地貌和气候气象的不同而有所差异;生态资产价值化潜力受到区位交通、资源禀赋、经济社会发展条件等多重因素影响,川西藏东、青东祁连的东部边缘地带价值化潜力更高、热点区更为集聚。基于生态资产禀赋及其价值化潜力划分为高资产-高潜力、高资产-低潜力、低资产-高潜力、低资产-低潜力四种分区类型,针对性提出了加大生态保护力度、合理开发生态资源、完善交通和服务设施、差异化开发生态产品等政策建议。  相似文献   

7.
金荞麦是蓼科荞麦属的多年生药用植物。为了研究我国野生金荞麦的分布特点,探明各地区的资源密度和遗传特性,我们依托第三次全国农作物种质资源普查与收集行动,考察了我国13个省(区),62个县(市、区),共采集到金荞麦种质资源530份。调查结果表明:我国野生金荞麦资源分布广泛,在调查范围内分布于90°44′28″~119°36′37″E、24°59′66″~33°53′16″N的广大区域,一般分布于海拔3500 m以下的亚热带季风气候区。金荞麦的群体数量和遗传特征呈现明显的区域差异,形成了西藏东南部高海拔的特殊类型集中分布区,西南地区中低海拔的遗传多样性富集区和长江中下游低海拔的遗传类型单一区的分布特点。野生群体中存在诸多优异材料,可在医药、保健、畜牧、观光、育种多个领域中开发利用。该研究在珍稀植物保护、荞麦属的分类进化研究、种质资源的创新利用和作物遗传改良等方面具有重要参考价值。  相似文献   

8.
利用9对SSR引物对山西省平榛(Corylus heterophylla Fisch)和毛榛(C.mandshurica Maxim.et Rupr.)野生居群、欧榛(C.avellana L.)和平欧杂种榛(C.heterophylla Fisch.×C.avellana L.)的人工栽培居群,共205个样本进行PCR扩增,共扩增出172个等位基因。每个位点的等位基因数为5~18个,平均等位基因数为12.5个。居群观测杂合度(Ho)和预期杂合度(He)的变化范围分别为0.395~0.665和0.778~0.906,表明榛属植物遗传多样性较高,其中平欧杂种榛的遗传多样性最高(He=0.867,I=2.271),毛榛遗传多样性最低(He=0.825,I=2.006)。不同物种居群间遗传分化系数FST=0.106,平均基因流Nm=2.609,表明居群间的遗传分化水平较低。各居群在大多数位点上偏离Hardy-Weinberg平衡,主要原因是人工选择或近交所致。分子方差分析(AMOVA)表明,遗传变异主要发生在物种居群内。NJ聚类结果显示毛榛和平榛多数个体聚在各自居群内,平欧杂种榛和欧榛个体交互混合组成一小支后再与平榛聚在一起,表明平欧杂种榛与欧榛、平榛的亲缘关系较近,而毛榛与其它3种榛属植物的亲缘关系较远。本研究还分析讨论了山西省榛属植物居群具有较高遗传多样性的原因,并提出了野生榛子的保护利用策略。  相似文献   

9.
野生沙葱的资源分布与保护利用   总被引:5,自引:0,他引:5  
分析了野生沙葱的资源分布、生态适应性、营养价值、研究与利用现状,提出了在全国范围内进行沙葱资源的分布范围、分布类型、种源特征、遗传变异、群落特征及其演替规律的调查与确定,建立沙葱的种质资源库和数据库,全面开展不同种源沙葱的迁地保护、生态适应性、保护生物学及人工优质丰产栽培技术研究等一系列保护、利用的思路与措施。  相似文献   

10.
椰甲截脉姬小蜂在中国的适生性分布   总被引:1,自引:0,他引:1  
研究极端温度对椰甲截脉姬小蜂Asecodes hispinarum Bouek存活的影响。在2℃、33℃和36℃恒温条件下放置48h后,该蜂羽化率较对照来说大大降低,基本上不能羽化;而在0℃和39℃恒温条件下即使只放置24h,该蜂全部死亡。在该实验的基础上,结合其它生态学特性的研究结果,利用地理信息系统ARC VIEW3.2分析预测该虫在我国的可能适宜分布范围。结果表明:椰甲截脉姬小蜂在我国的最适宜分布范围在16.53°~19.1°N,108.61°~112.33°E,只集中在海南省的南部;适宜分布范围大体在20.03°~24.27°N,101.98°~117.65°E,集中在海南、广东、广西、云南和福建5省;潜在分布范围大体在23.3°~33.4°N,98.5°~122.1°E,主要集中在西南、华东、华中等地区的172个县。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.  相似文献   

18.
We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf) and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair, K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements.  相似文献   

19.
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   

20.
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   

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