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1. chinaXiv:202104.00053 [pdf]

黄土高原苹果树叶片气孔导度的环境响应与模拟

苗玉
Subjects: Biology >> Ecology

气孔导度(gs)是衡量植物与外界环境中水、CO2 等物质交换速率的重要参数,其观测与模拟 可以有效指示物质交换情况及各项生理参数。通过 LI-6400 便携式光合测定仪对黄土高原苹果树 叶片各项生理参数进行观测,分析 gs 日变化特征及其与环境因子的响应关系,运用 Jarvis 模型和 Ball-Woodrow-Berry(BWB)模型对 gs 进行模拟。研究结果显示:(1)黄土高原苹果树 gs 日变化在气 温较高、辐射较强的 8、9 月观测日内呈双峰曲线。上午(8:00—12:00)随着太阳辐射逐渐增强,气孔 张开,gs 在 11:00—13:00 出现第一次峰值;中午(12:00—14:00)由于气温(Ta)升高,为避免细胞散失 过多水分,气孔关闭出现短暂的“光合午休”现象;午后(14:00—18:00),随着 Ta、光合有效辐射(PAR)下降,gs 逐渐增加并在 15:00—17:00 出现第二次峰值。(2)通过灰色关联度分析,发现 gs 与各 环境因子的关联程度依次为:PAR(0.731)>CO2 浓度(Ca,0.712)>饱和水汽压差(VPD,0.702)>Ta(0.689)>相对湿度(hs,0.673)。gs 与各环境因子的响应关系表现为:随 PAR、Ta、Ca、hs 的增大而增大, 随 VPD 的增大而减小。(3)从 gs 的模拟结果可以看出,Jarvis 模型的决定系数(0.678)、修正效率系数(0.335)和修正一致系数(0.803)均优于 BWB 模型各值(0.329、-1.630、0.138),而平均绝对误差 (0.103)小于 BWB 模型(0.143),表明 Jarvis 模型模拟效果较好。通过对黄土高原苹果树叶片 gs 环境 响应与模拟的分析研究,对于掌握苹果树叶片一天内不同时刻对水分的需求变化,进一步提高该地区苹果树种植的水资源利用效率具有重要意义。

submitted time 2021-04-14 From cooperative journals:《干旱区地理》 Hits22Downloads8 Comment 0

2. chinaXiv:202104.00056 [pdf]

陇中黄土高原区旱地春小麦产量 对干旱胁迫响应的模拟研究

王钧; 李广
Subjects: Biology >> Ecology

为进一步探明陇中黄土高原区旱地春小麦产量形成对不同干旱胁迫的响应机制,依据甘肃 省定西市安定区凤翔镇安家沟村 2016—2018 年大田控水试验数据以及定西市安定区 1971—2018 年气象数据,验证农业生产系统模拟(Agricultural production systems simulation,APSIM)模型模拟不 同干旱胁迫旱地春小麦产量及产量构成要素的适宜性,基于 APSIM 模型分析不同生育期、不同程 度干旱胁迫对旱地春小麦籽粒数、千粒重和产量的影响,利用多元逐步回归方程确定陇中黄土高 原区旱地春小麦最佳灌水时间和灌水量。结果表明:(1)APSIM 模型模拟陇中黄土高原区旱地春 小麦生育期、籽粒数、千粒重和产量的均方根误差(Root mean square error,RMSE)均小于 3.67 d、300.52 个·m-2、2.56 g、267.43 kg·hm-2,归一化均方根误差(Normalized root mean square error,NRMSE) 均小于 3.89%、2.86%、9.71%、11.58%,模型有效性指数(Model effectiveness index,ME)均大于 0.62、 0.78、0.60、0.66,表明 APSIM 模型对模拟干旱胁迫条件下陇中黄土高原区旱地春小麦产量形成具有 较好的适应性。(2)不同生育期干旱胁迫下,拔节期干旱胁迫对小麦籽粒数影响最大,其次由大到 小依次为出苗期、分蘖期、无胁迫、抽穗期、开花期和灌浆期;灌浆期干旱胁迫对小麦千粒重影响最 大,其次由大到小依次为开花期、抽穗期、无胁迫、拔节期、出苗期和分蘖期;拔节期干旱胁迫对小 麦产量影响最大,其次由大到小依次为灌浆期、抽穗期、开花期、出苗期、无胁迫和分蘖期。(3)不同 程度干旱胁迫下,灌水量 300.00 mm 旱地春小麦产量最大为 4866.19 kg·hm-2,与其他 4 种灌水相比 产量分别增加 283.53%、39.65%、0.46%和 15.58%。(4)出苗后第 1 d、47 d、60 d、82 d、86 d 灌水,且灌 水量达到 343.09 mm 时,旱地春小麦产量最大为 5578.91 kg·hm-2。干旱胁迫发生时间和程度对研 究区小麦产量形成具有明显的交互作用,分蘖期适度干旱胁迫有利于提高陇中黄土高原区旱地春 小麦产量,而拔节期和灌浆期为旱地春小麦田间水分管理的关键生育期,小麦生长发育过程中应 加强该生育期的水分管理以提高陇中黄土高原区粮食产量。

submitted time 2021-04-14 From cooperative journals:《干旱区地理》 Hits12Downloads2 Comment 0

3. chinaXiv:202104.00064 [pdf]

泛基因组研究在遗传多样性和功能基因组学中的应用

向坤莉; 贺文闯; 邹益; 彭丹; 张晓妮; 廖雪竹; 王杰; 杨健康; 武志强
Subjects: Biology >> Botany >> Applied botany

相对于单个参考基因组仅聚焦于个体遗传信息的挖掘,泛基因组研究则能够反映整个物种或类群全部的遗传信息。随着基因组测序和分析技术的不断发展,泛基因组学逐渐成为新的研究热点,并已在植物、动物和微生物多个物种中获得了广泛应用,为全面解析物种或类群水平的遗传变异和多样性、功能基因组和系统进化重建等研究提供了强有力的工具,取得了很多显著的研究成果。尽管如此,由于泛基因组学研究尚处于发展阶段,测序费用和分析成本仍然较高,难以广泛普及;且存在分析标准不一、数据挖掘不够全面深入、理论难以应用于生产实际等尚待解决的问题,仍有较大的发展空间。该文系统总结了泛基因组在生物遗传多样性挖掘和功能基因组学中的研究进展,主要包括其在泛基因组图谱的构建、基因组变异和有利基因的发掘、功能基因的多态性、群体遗传多样性和系统进化等多个领域中的应用和研究,探讨了其在不同领域的应用潜力。同时,讨论了目前泛基因组研究中存在的局限性和可能的解决方法,并对其将来的发展前景进行了展望。

submitted time 2021-04-13 From cooperative journals:《广西植物》 Hits11Downloads3 Comment 0

4. chinaXiv:202104.00023 [pdf]

动脉粥样硬化ApoE-/-小鼠模型尿液蛋白质组学变化探究

华元瑞; 孟文书; 魏静; 刘永涛; 高友鹤
Subjects: Biology >> Biochemistry

心血管疾病是当今世界第一大致死因素,动脉粥样硬化是其重要病理基础,其早期诊断具有重要意义。尿液更利于积累和反应机体生理状态的变化且不受到稳态机制的调节,是疾病早期生物标志物的良好来源。本文通过高脂饮食诱导ApoE-/-小鼠5个月构建动脉粥样硬化动物模型,选取七个时间点收集实验组及正常饮食对照组c57BL/6小鼠尿液样品,使用蛋白质组学分析方法,进行自身对照和组间对照。自身对照结果表明高脂饮食1周前后尿液蛋白质组差异显著,同时多种差异蛋白被报道过与动脉粥样硬化相关或可作为其生物标志物。组间对照结果表明差异蛋白GO分析得出的生物学过程能够对应疾病发生发展的进程。两种对照方式得到的差异性化学修饰也多被报道与该疾病进程相关。实验证明了尿液蛋白质组学有敏锐监测机体变化的潜力,为寻找动脉粥样硬化早期生物标志物提供了可能。

submitted time 2021-04-08 Hits49Downloads22 Comment 0

5. chinaXiv:202104.00021 [pdf]

“One-to-three” droplet generation-based digital microfluidics for parallel immunoassay.docx

Kai, Jin; Chenxuan, Hu; Siyi, Hu; Jinhua, Li; Hanbin, Ma
Subjects: Biology >> Bioengineering

In digital microfluidics, droplet generation is the fun, as the basis for a series of droplet manipulations including mixing, separation, dispensing, etc., has always been the focus in the field of digital microfluidics. Currently, the performance of DMF-based droplet splitting is highly influenced by the ratio of electrode size and the gap between the upper and lower plates. Here we propose a "one to three" droplet splitting method. In "one to three" spitting method, a pair of opposite electrowetting forces are applied to the droplet. As the electrowetting force is applied on the splitting position, a middle child droplet and two mother liquid droplets generate. The aspect ratio of child droplet is close to 1:2. "One to three" spitting method is then applied to magnetic beads immunoassay. Magnetic beads are retained in child droplets under small magnetic force with high magnetic bead washing efficiency. Simultaneous detection of five B-type natriuretic peptide analyte samples are performed on a single chip within 10 minutes. Correlation coefficient (R2) of the calibration curve was 0.9942, and the detection limit was less than 5pg/mL. This unique method of digital microfluidic droplet splitting has great potential in other application fields.

submitted time 2021-04-07 Hits134Downloads61 Comment 0

6. chinaXiv:202104.00005 [pdf]

Taxonomic revision of the holotype of Proboselaphus watasei Matsumoto, 1915 (Bovidae, Artiodactyla) from Chuanyu area, China

NISHIOKA Yuichiro; KOHNO Naoki; KUDO Yuichiro
Subjects: Biology >> Zoology

A taxonomic revision of Proboselaphus watasei Matsumoto, 1915 (Bovidae, Artiodactyla) from the Pleistocene of Chuanyu area, China demonstrates that this genus and species names are invalid. The holotype with a skull and mandibles was recently rediscovered in the fossil collection by Nobuo Naora, which is housed in the National Museum of Japanese History, Chiba Prefecture, Japan. Proboselaphus watasei was described as a closely-related species to living nilgai, or Boselaphus tragocamelus, in South Asia, based on general characteristics of pecorans, such as small bony horn-cores and hypsodont cheek teeth. However, the cranial and dental morphologies re-examined in the present study clearly show that the holotype has cervid-specific characteristics: e.g., the fronto-parietal surface curving dorsally, the basioccipital with a triangular outline, and molars with isolated anterior and posterior lobes. The molars of the holotype are comparable to those of Cervus unicolor, in having strong accessary structures (or spurs, cingulums/cingulids, and styles/stylids), and are as large as those of Cervus cf. C. unicolor from the Pleistocene deposits in southern China. This taxonomic change suggests that any crown-boselaphins had not dispersed into East Asia since the Pleistocene.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits175Downloads79 Comment 0

7. chinaXiv:202104.00006 [pdf]

Climate change and evolution of early lagomorphs (Mammalia): a study perspective based on new materials of Ordolagus from Nei Mongol (northern China)

Chiara ANGELONE; ZHANG Zhao-Qun
Subjects: Biology >> Zoology

The Early Oligocene is a critical time for global climate changes in the Cenozoic. This epoch witnessed severe mammalian faunal turnovers known as “Grande Coupure” in Europe and “Mongolian Remodelling” in Asia. However, insights about morphological changes in Oligocene mammal lineages have not been explored in detail. One of the least diversified groups of recent mammals, lagomorpha, is globally common in the fossil records, especially in Asia. During the Oligocene, many Eocene archaic lagomorph taxa died out and were replaced by more advanced forms. New findings from Nei Mongol and re-examination of the specimens from older collections enabled a revision of a common Asian lagomorph genus, Ordolagus, which possibly has a close affinity with the Middle–Late Eocene genus Gobiolagus. In Nei Mongol, we recognized the presence of Ordolagus during the basal Early Oligocene. Comparisons with coeval and slightly older lagomorph taxa from Asia and North America show that Ordolagus attained some salient tooth morphological characters (i.e., development of anteroconid on p3, full hypselodonty of cheek teeth, and lingual connection of trigonid and talonid on p4–m2), which are also the key features of modern leporids. The appearance of those morphologic features in Ordolagus is coeval to major global or regional climatic changes. Further investigations on Asian early lagomorphs compared with the study of other small mammals and local climatic factors will be essential to refine the role of lagomorphs as palaeoclimatic proxies.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits146Downloads63 Comment 0

8. chinaXiv:202104.00007 [pdf]

An Upper Miocene “Hipparion fauna” locality sandwiched by basalts in Hanjiaying, Nei Mongol

WANG Qian;LIU Yan;WANG Li-Hua; Mikael FORTELIUS; ZHANG Zhao-Qun
Subjects: Biology >> Zoology

Here we report a Hipparion fauna locality discovered in between two basalt layers near Hanjiaying Village, Jining District, Wulanchabu City, Nei Mongol. K-Ar isotopic dating of the lower and upper level of the basalt constrains the age of the fauna from 7.2 to 6.8 Ma. Compared with classical Hipparion fauna from northern China, the Hanjiaying fauna is closer to those from Baode of Shanxi, Siziwang Banner of Nei Mongol and the Linxia Basin of Gansu. It is similar to the Loc. 43, 44 and 49 from Baode by faunal composition, confirming their age to be ~7.0 Ma rather than 5.5 Ma. The high similarity with the fossils from Wulanhua, Siziwang Banner, Nei Mongol, verified the age of Wulanhua fauna at about 7 Ma. Compared with faunas from the Linxia Basin, Gansu, it is more similar to those from the upper part of the Liushu Formation, especially the Yangjiashan fauna. Based on the faunal composition and their tooth morphology, the Hanjiaying fauna could be included in the “Gazella dorcadoides” fauna, which is supposed to be at the west paleobiome in northern China during the Late Miocene.

submitted time 2021-04-02 From cooperative journals:《古脊椎动物学报》 Hits98Downloads38 Comment 0

9. chinaXiv:202104.00008 [pdf]

桂林岩溶石山落叶阔叶林种类组成及其环境解释

林红玲; 梁士楚; 姚义鹏; 姜勇; 包含; 农彩汪; 宋静; 黄佳; 甘鑫梅
Subjects: Biology >> Botany >> Applied botany

落叶阔叶林是亚热带岩溶石山典型的森林植被类型之一,为了了解此类森林植被的群落类型和组成结构,本研究在桂林阳朔县和灵川县岩溶生境典型的落叶阔叶林内设置了 49 个 20 m× 20 m 的随机样方,在野外调查的基础上进行群落数量分类和排序,对其群落类型进行划分。在此基础上对不同类型的群落种类组成、结构及其分布与环境因子的耦合关系进行深入分析。结果表明:(1)桂林岩溶石山落叶阔叶林可划分 3 个群丛组类型,即群丛组 A:南酸枣-喜树+巴豆群丛组(ASS. Choerospondias axillaris-Camptotheca acuminata+Croton tiglium),群丛组 B:光皮梾木-喜树群丛组(ASS. Swida wilsoniana-Camptotheca acuminata),群丛组 C:麻栎-檵木群丛组(ASS. Quercus acutissima-Loropetalum chinense)。(2)不同群落类型中常绿和落叶物种的丰富度、多度、胸高断面积及重要值的变化:在乔木层中,3 个群丛组均为落叶物种占优势;在灌木层中,群丛组 A、B 以落叶物种占优势,群丛组 C 以常绿物种占优势。(3)在 1~5 cm 和5~10 cm 径级内,群丛组 A 和 B 的落叶物种在 4 个度量指标上均大于常绿物种,群丛组 C 除了物种丰富度以外,均为常绿物种大于落叶物种;在 ≥10 cm 径级中,除了群丛组 B 的物种丰富度外,3 个群丛组中的各项指标均为落叶物种占主导地位。(4)岩石裸露率、海拔、坡向、土壤含水量、土壤 pH、土壤有机质、全氮、速效氮、速效钾、林冠开阔度和人为干扰是影响研究区不同类型群落分布的主要环境因子。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits120Downloads66 Comment 0

10. chinaXiv:202104.00009 [pdf]

中国仙人掌科一新归化种——匍地仙人掌

王琦; 严靖
Subjects: Biology >> Botany >> Applied botany

在进行多肉植物资源调查时,在我国山东发现一仙人掌科仙人掌属新记录种——匍地仙人掌[Opuntia humifusa (Raf.) Raf.]。该种具有独特的匍匐生长习性,叶状茎深绿色,无白霜,无针状刺,花黄色,与国内分布的仙人掌属其他物种区别明显。匍地仙人掌原产于北美洲,是仙人掌科为数不多的耐寒种类之一,现归化于中国山东省日照市五莲县,系目前发现的在我国野外分布最北的仙人掌科植物。该种可能于? 20 世纪? 50 年代在国家推广中药材时期引入种植,人类活动致使其种群逐渐扩散。同时,对匍地仙人掌与江苏报道的二色仙人掌之间的分类学问题进行了论述,并对将来匍地仙人掌在我国暖温带地区合理的开发利用进行了展望。

submitted time 2021-04-02 From cooperative journals:《广西植物》 Hits94Downloads42 Comment 0

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