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1.
GENALEX软件是一种在Microsoft Excel程序中运行的跨操作系统平台的居群遗传分析软件包,它可以对共显性数据、单倍体数据和二元数据进行分析。GENALEX还提供了一系列基于频率的分析。例如,GENALEX可进行F统计检验、Nei’s遗传距离和地理距离的同一性检验以及偏性分布的检验。基于距离的计算如AMOVA分析、相关性PCA分析、Mantel检验、居群遗传变异的空间自相关分析和TWOGENER分析也能够在GENALEX中实现。该软件包还提供了20多种不同的图表总结数据已经辅助检测。除此之外,序列信息和基因型数据可以方便地在相关软件中转化格式。最初以辅助教学为目的设计的GENALEX软件现在也为研究人员提供了可以应用的功能。  相似文献   

2.
中国基因组生物信息学回顾与展望   总被引:1,自引:0,他引:1  
顾坚磊  周雁 《中国科学C辑》2008,38(10):882-890
基因组生物信息学是随着大规模基因组测序而兴起的一门交叉学科, 其研究对象是基因组数据. 因此, 对基因组数据的各方面的深入了解, 有助于把握基因组生物信息学的来龙去脉. 本文从基因组数据展开, 围绕着这些数据的收集、储存、分析和比较, 分别列举了相关的数据库、算法和软件包. 今天, 由新一代测序技术所带来的对数据处理、算法设计和功能信息挖掘等技术和研究方面的挑战, 应该及时得到充分的重视.  相似文献   

3.
FACE条件下水稻冠层蒸散和水分利用率的模拟   总被引:1,自引:0,他引:1  
利用开放式CO2浓度增高(FACE)系统平台,通过在水稻拔节期至成熟期对水稻冠层微气候及相关生理指标的连续观测,并结合能量平衡分析,模拟研究了FACE对水稻冠层蒸散和水分利用率的影响.结果表明:将水稻叶片气孔导度与光合有效辐射、饱和水气压差的定量关系与Penman-Monteith方程相结合,可以较好地模拟FACE和对照条件下的水稻蒸散量;观测期间,CO2浓度升高使水稻的水分利用比对照减小约10 mm,结合水稻生物量增加12%,FACE条件下水稻水分利用率(WUE)增加约12%.  相似文献   

4.
化石燃料的燃烧和城市化进程的加快导致大气中二氧化碳(CO_2)和臭氧(O_3)浓度日益升高,大气气体浓度的变化会对植物个体和陆地生态系统结构与功能产生影响。CO_2浓度升高增加了陆地生态系统碳汇能力,而O_3导致作物减产和生态系统固碳损失。自由空气中气体浓度增加(FACE)系统是最接近自然的一种模拟大气气体浓度增加对生态系统影响的研究平台,已广泛应用于各种生态系统,为理解陆地生态系统生态过程对全球变化的响应及评估未来情景的生态风险提供了重要科学依据。该文从FACE技术特点出发,介绍了国内外建成的大型CO_2/O_3-FACE系统,分析了FACE系统的不同布气方式在不同生态系统研究过程中的优点与缺点,概述了全球FACE运行的现状和取得的主要成果,并指出了FACE系统存在的主要问题和前沿研究方向。  相似文献   

5.
化石燃料的燃烧和城市化进程的加快导致大气中二氧化碳(CO2)和臭氧(O3)浓度日益升高, 大气气体浓度的变化会对植物个体和陆地生态系统结构与功能产生影响。CO2浓度升高增加了陆地生态系统碳汇能力, 而O3导致作物减产和生态系统固碳损失。自由空气中气体浓度增加(FACE)系统是最接近自然的一种模拟大气气体浓度增加对生态系统影响的研究平台, 已广泛应用于各种生态系统, 为理解陆地生态系统生态过程对全球变化的响应及评估未来情景的生态风险提供了重要科学依据。该文从FACE技术特点出发, 介绍了国内外建成的大型CO2/O3-FACE系统, 分析了FACE系统的不同布气方式在不同生态系统研究过程中的优点与缺点, 概述了全球FACE运行的现状和取得的主要成果, 并指出了FACE系统存在的主要问题和前沿研究方向。  相似文献   

6.
水稻产量及其构成因子对空气CO2浓度增高响应的QTL分析   总被引:3,自引:0,他引:3  
自由空气CO2浓度增加设施(Free air carbon dioxide enrichment.FACE)使得实际地模拟未来植物生长所处的CO2浓度增加环境变为可能。FACE下.作物生长和产量发生不同程度的加速和提高,而分析作物产量因子对CO2浓度增加响应的遗传基础将有利于对CO2环境变化做出敏感响应的遗传特性的认识,有利于适合未来空气CO2浓度增加环境的高产品种的培育。以粳稻品种Asominori与籼稻品种IR24的杂交组合所衍生的染色体片段置换系(CSSLs)为材料进行田间试验,分别在FACE(约570umol CO2/mol)和正常大气(约370umol CO2/mol)下对籽粒产量及其构成因子等数量性状位点(QTL)进行了分析。结果表明,在FACE下,Asominori和IR24的有效穗数、穗粒数和单株籽粒产量均显著高于对照下的,并且FACE下,65个置换系的变幅范围均大于对照下的;在第1.2,4,6.7,9和12染色体上检测到LOD值在2.5—5.7范围内的控制上述产量性状的20个QTL.其中有3个可以同时在FACE和正常大气下检测到.其余的则只是在某一种CO2环境下检测到。此外,还检测到2个QTL(qFT12 and qGP4)存在着与环境的加性互作效应。可以推论.空气中CO2浓度的增加诱导了部分对CO2浓度敏感的QTL表达,控制水稻产量性状的QTL与CO2增加的环境发生了互作效应。预计利用分子标记辅助育种途径可以培育出适用于未来CO2浓度增加环境下的高产水稻品种。  相似文献   

7.
FACE水稻生育期模拟   总被引:7,自引:0,他引:7  
利用农田开放式空气CO2浓度增高(FACE)技术平台,设置大气CO2浓度比对照高200μmol mol^-1的FACE处理和不同的施N量水平,以水稻钟模型为基础,构建了FACE水稻生育期模拟模型。通过不同年度试验数据的检验,表明模型对CK及FACE条件下水稻不同生育期天数的预测性能好。不同生育期预测误差的根均方差(RMSE)最大为2.64d,最小只有0.15d,且相关系数均达到了极显著水平。说明FACE水稻生育期模型具有较高的预测性和适用性。  相似文献   

8.
大田栽培条件下,研究了开放式大气CO2浓度提高(FACE)200 μmol·mol-1对粳稻品种武香粳14各生育期功能叶片硝酸还原酶活力(NRA)的影响.结果表明,FACE明显提高了各生育期功能叶片NRA,拔节期、孕穗期、抽穗期、穗后10 d、穗后20 d水稻功能叶片NRA平均值分别比对照提高了50%、20%、60%、80%和30%,其中,FACE处理对拔节期、抽穗期和穗后10 d水稻功能叶片NRA水平影响较大.施氮处理明显影响了FACE条件下水稻功能叶片NRA,并且在不同生育期存在不同的趋势:拔节期,中氮>低氮>高氮;孕穗期和抽穗期,高氮>中氮>低氮;而穗后10 d及20 d则为中氮>高氮>低氮.FACE处理与施氮量对NRA存在互作效应,拔节期及穗后20 d两者互作效应达极显著水平,穗后10 d达显著水平,而孕穗期及抽穗期互作效应不显著.  相似文献   

9.
稻米品质性状对开放式空气二氧化碳浓度增高的响应   总被引:17,自引:4,他引:13  
利用开放式空气CO2浓度增高(FACE)系统平台。研究大田栽培条件下粳稻武香粳14号稻米品质性状对CO2浓度增高200μmol·mol^-1的响应。结果表明.FACE处理稻谷的出糙率平均比CK高1.4个百分点,整精米率平均比CK低12.3个百分点,较低的供N水平有利于提高FACE条件下的出糙率.较高的供N水平有利于提高FACE条件下的整精米率;FACE处理的稻米垩白略有增加。垩白粒率平均比CK高11.9个百分点,垩白度平均比CK平均高2.8个百分点,较高的供N和供P水平有利于降低FACE条件下垩白大小、垩白粒率和垩白度;FACE处理稻米糊化温度平均比CK平均高0.52℃,胶稠度有提高的趋势,但对稻米直链淀粉含量影响较小,较高的供N和供P水平有利于降低FACE条件下稻米的直链淀粉含量,较低的供N和较高的供P水平有利于降低FACE条件下稻米胶稠度,较低的供N水平有利于降低FACE条件下稻米糊化温度;FACE处理使稻米蛋白质含量比CK平均低0.6个百分点,较低的供N和供P水平有利于降低FACE条件下稻米蛋白质含量。  相似文献   

10.
开放式空气C02浓度增高对水稻冠层能量平衡的影响   总被引:3,自引:1,他引:2  
大气CO2浓度升高对植物冠层能量平衡的影响是导致植物生长发育和水分利用率发生变化的环境物理原因.利用位于江苏省无锡市安镇的农田自由开放式空气CO2浓度增高(FACE)系统平台,进行水稻冠层微气候和土壤热通量的连续观测,并结合能量平衡分析,研究了FACE对水稻冠层能量平衡的影响.结果表明,水稻冠层显热和潜热通量FACE与对照的差异日最大值出现在14:00左右,与空气相对湿度日最低值出现时间一致;潜热通量FACE与对照的差异日最大值变化在—15-—65J·m^-2·s^-1之间,显热通量FACE与对照的差异最低值变化在12—55J·m^-2·s^-1之间;显热和潜热通量FACE与对照的差异日最大值随冠层上方辐射平衡增加而增大.水稻冠层白天总显热通量FACE均高于对照,而总潜热通量FACE均低于对照.白天总显热和潜热通量FACE与对照的差异在同一生育期内随冠层上方净辐射增强而增大,在不同生育期随生育期推进而减少.开花期至蜡熟期,水稻冠层白天总潜热通量FACE比对照平均低6.7%.FACE使水稻冠层白天总显热通量及其占冠层上方辐射平衡的比例减少,而使总潜热通量及其占冠层上方辐射平衡的比例增大,但对土壤热通量及夜间显热和潜热通量的影响不大.开花期至蜡熟期水稻冠层白天总显热、潜热通量占冠层上方净辐射总量的比例FACE与对照之差平均为5.5%.  相似文献   

11.
稻麦轮作FACE系统平台I.系统结构与控制   总被引:49,自引:4,他引:45  
在稻麦轮作水稻田建立FACE系统 (Free AirCO2 Enrichment) ,即CO2 浓度的控制和监测系统平台 .利用计算机网络系统对平台的CO2 浓度进行监测控制 ,根据大气中的CO2 浓度、风向、风速 ,作物冠层高度的CO2 浓度及昼夜等因素的变化调节CO2 气体的释放速度及方向 ,实现FACE圈的CO2 浓度高于周围大气CO2 浓度 2 0 0 μmol·mol-1.试验表明 ,影响控制精度的主要因素有风速、作物和土壤呼吸作用和扩散层高度 .经过控制方程参数调整 ,在白天 ,控制精度达到 80 %的时间占总时间的白天达到 83% ,夜晚为6 8% .FACE圈内的CO2 分布基本均匀 .平均CO2 设置浓度白天为 5 5 7mol·mol-1,晚上为 6 0 8mol·mol-1.圈内CO2 浓度分布基本上沿放气管对称分布 ,由边沿向中心逐步降低 .2 0 0 1年水稻生长季节平均控制精度 (TAR)达到白天 1.0 3和晚间 1.0 9.  相似文献   

12.
Abstract  The Australian Plague Locust Commission (APLC) is responsible for the monitoring and control of locust populations that pose a threat to agriculture in the inland areas of four Australian States, a total area of 2 million km2. A GIS-based decision support system (DSS) is used to co-ordinate the collection, processing, analysis and display of a range of spatial data for the forecasting of locust population development and to assist control operations. The resultant forecasts are used to help locate population aggregations early in a breeding sequence so as to enable effective preventive control. The data collection components of the DSS include wireless direct transfer of locust survey data from the field and daily internet collections of weather data. Locust distribution and age information is collected by APLC officers on regular vehicle surveys using GPS-connected palmtop computers, and sent directly to a GIS server via high frequency (HF) radio modems. Locust reports from landholders and state extension staff are also incorporated into the system. The current survey data are used to estimate broad distributions, and to seed spatially-explicit development models that can identify the timing of life stages that can be effectively managed. Information on the distribution of rainfall, temperature and wind-fields is collected automatically from the internet and integrated with habitat information and locust distributions. Online weather data products from the Bureau of Meterology are also accessed regularly to assist in operational decision making.  相似文献   

13.
Dendrometers are vital tools for studying the response of trees to intra-annual environmental changes in different temporal resolutions, ranging from hourly, daily to weekly time resolution. Dendrometers are increasingly used in forest management and tree physiological studies. Besides the data analysis, data processing is also challenging, time-consuming and potentially error-prone due to the immense number of measurements generated by self-registering electronic dendrometers. We present the package ‘dendRoAnalyst’ based on R statistical software to process and analyse dendrometer data using various approaches. This package offers algorithms for handling and pre-cleaning of dendrometer data before the application of subsequent data analytical steps. This includes identifying and erasing artefacts in dendrometer datasets not related to actual stem circumference change, identifying data gaps within records, and the possibility of change(s) in temporal resolution. Furthermore, the package can calculate different daily statistics of dendrometer data, including the daily amplitude of tree growth. The package dendRoAnalyst is therefore intended to facilitate researchers with a collection of functions for handling and analysing dendrometer data.  相似文献   

14.
With the rapidly growing number of data publishers, the process of harvesting and indexing information to offer advanced search and discovery becomes a critical bottleneck in globally distributed primary biodiversity data infrastructures. The Global Biodiversity Information Facility (GBIF) implemented a Harvesting and Indexing Toolkit (HIT), which largely automates data harvesting activities for hundreds of collection and observational data providers. The team of the Botanic Garden and Botanical Museum Berlin-Dahlem has extended this well-established system with a range of additional functions, including improved processing of multiple taxon identifications, the ability to represent associations between specimen and observation units, new data quality control and new reporting capabilities. The open source software B-HIT can be freely installed and used for setting up thematic networks serving the demands of particular user groups.  相似文献   

15.
随着农作物种质资源数量的不断增加,种质资源交流的日益频繁以及种质资源利用的逐步深入,农作物种质资源数据库的建设对农作物的应用研究和基础性研究至关重要。上海市农业生物基因中心借助于本中心保存的近21万份种质资源的信息,开发了一套上海农作物种质资源数据库,本文主要阐述了该数据库设计和构建的目的、原则和数据库的架构、运行环境以及主要功能模块。上海农作物种质资源数据库采用了B/S结构,平台系统利用多层逻辑架构实现了对农作物种质资源数据信息的收集、存储、查询、统计分析等功能。外部用户通过浏览器即可访问平台系统,浏览查询种质资源信息。内部管理员可使用平台的受限功能,需要认证成功后才可使用后台管理功能,实现对整个平台数据的管理。注册用户还可通过基因资源数据库提交引种申请,管理员结合管理信息系统实现对外供种全流程的网络化,借此可提高工作效率,增加工作流程的透明度。  相似文献   

16.
基于GIS的澳大利亚蝗虫治理决策支持系统的运行   总被引:5,自引:0,他引:5  
澳大利亚疫蝗委员会(APLC)负责澳大利亚内陆四个州2000000km^2上严重威胁农业生产的蝗虫种群的监测与防治。应用一个基于GIS的“决策支持系统(DSS)”采集,处理,分析并显示多种空间数据,以预测蝗虫种群的发育并辅助实施防治。所做预测有助于对蝗群集聚区做出早期定位并采取有效的预防措施。该DSS的数据采集包括田间调查资料的无线直传和网上逐日天气资料的下载,蝗群的分布和年龄结构信息通过定期GPS定位调查获得,并连同农场主和地方农技推广人员的虫情报告通过高频调制直接传至APLC总部的GIS服务器上;当前的调查资料用于估测蝗群的分布并作为空间发育模型的输入数据以确定实施防治的最适发育阶段的始期;降水分布和风温场资料从网上自动下载并与栖境条件和蝗群分布信息集成。同时,澳大利亚联邦气象局的在线天气资料及产品也从网上定时存取用于决策支持。  相似文献   

17.
A free-air CO2 enrichment (FACE) system was designed to permit the experimental exposure of tall vegetation such as stands of forest trees to elevated atmospheric CO2 concentrations ([CO2]a) without enclosures that alter tree microenvironment. We describe a prototype FACE system currently in operation in forest plots in a maturing loblolly pine (Pinus taeda L.) stand in North Carolina, USA. The system uses feedback control technology to control [CO2] in a 26 m diameter forest plot that is over 10 m tall, while monitoring the 3D plot volume to characterize the whole-stand CO2 regime achieved during enrichment. In the second summer season of operation of the FACE system, atmospheric CO2 enrichment was conducted in the forest during all daylight hours for 96.7% of the scheduled running time from 23 May to 14 October with a preset target [CO2] of 550 μmol mol–1, ≈ 200 μmol mol–1 above ambient [CO2]. The system provided spatial and temporal control of [CO2] similar to that reported for open-top chambers over trees, but without enclosing the vegetation. The daily average daytime [CO2] within the upper forest canopy at the centre of the FACE plot was 552 ± 9 μmol mol–1 (mean ± SD). The FACE system maintained 1-minute average [CO2] to within ± 110 μmol mol–1 of the target [CO2] for 92% of the operating time. Deviations of [CO2] outside of this range were short-lived (most lasting < 60 s) and rare, with fewer than 4 excursion events of a minute or longer per day. Acceptable spatial control of [CO2] by the system was achieved, with over 90% of the entire canopy volume within ± 10% of the target [CO2] over the exposure season. CO2 consumption by the FACE system was much higher than for open-top chambers on an absolute basis, but similar to that of open-top chambers and branch bag chambers on a per unit volume basis. CO2 consumption by the FACE system was strongly related to windspeed, averaging 50 g CO2 m–3 h–1 for the stand for an average windspeed of 1.5 m s–1 during summer. The [CO2] control results show that the free-air approach is a tractable way to study long-term and short-term alterations in trace gases, even within entire tall forest ecosystems. The FACE approach permits the study of a wide range of forest stand and ecosystem processes under manipulated [CO2]a that were previously impossible or intractable to study in true forest ecosystems.  相似文献   

18.
19.
介绍了农田FACE(free airCO2 enrichment)试验中的NO和NO2 地 气交换观测方法 ,即静态暗箱采样—NO和NO2 化学发光分析法 ,并对观测结果进行了分析讨论 .此观测方法简单、易于操作 ,并可获得可靠的NO和NO2 净交换通量观测结果 .在稻麦轮作农田的旱地阶段 ,无论FACE还是对照处理 ,NO主要表现为地面净排放 ,NO2 主要表现为地面净吸收 .逐日的NO净排放不依赖于土壤温度 ,但却与土壤含水量呈线性负相关 (R2 =0 .82 ,P <0 .0 0 1) .NO2 净吸收具有明显的季节变化特征 ,逐日的净吸收通量随土壤温度和土壤含水量的变化可分别用抛物线方程拟合 (温度 :R2 =0 .74 ,P <0 .0 0 1;含水量 :R2 =0 .6 9,P <0 .0 0 1) .大气CO2 浓度升高 2 0 0± 4 0 μmol·mol-1使NO净排放减弱 19% (t 检验P =0 .0 96 ) ,NO2 净吸收减弱 10 % (t 检验P =0 .2 6 ) ,这主要是植物生长受到促进的缘故 .  相似文献   

20.

Background

syndromic surveillance system has great advantages in promoting the early detection of epidemics and reducing the necessities of disease confirmation, and it is especially effective for surveillance in resource poor settings. However, most current syndromic surveillance systems are established in developed countries, and there are very few reports on the development of an electronic syndromic surveillance system in resource-constrained settings.

Objective

this study describes the design and pilot implementation of an electronic surveillance system (ISS) for the early detection of infectious disease epidemics in rural China, complementing the conventional case report surveillance system.

Methods

ISS was developed based on an existing platform ‘Crisis Information Sharing Platform’ (CRISP), combining with modern communication and GIS technology. ISS has four interconnected functions: 1) work group and communication group; 2) data source and collection; 3) data visualization; and 4) outbreak detection and alerting.

Results

As of Jan. 31st 2012, ISS has been installed and pilot tested for six months in four counties in rural China. 95 health facilities, 14 pharmacies and 24 primary schools participated in the pilot study, entering respectively 74256, 79701, and 2330 daily records into the central database. More than 90% of surveillance units at the study sites are able to send daily information into the system. In the paper, we also presented the pilot data from health facilities in the two counties, which showed the ISS system had the potential to identify the change of disease patterns at the community level.

Conclusions

The ISS platform may facilitate the early detection of infectious disease epidemic as it provides near real-time syndromic data collection, interactive visualization, and automated aberration detection. However, several constraints and challenges were encountered during the pilot implementation of ISS in rural China.  相似文献   

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