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1.
Facilitating access to journals for a multidisciplinary field of study requires an understanding of the literature used by those researchers. This study examines the journals used for publication and those cited by 85 faculty affiliates of the New Mexico State University (NMSU) Water Science and Education Center (WSEC), a multidisciplinary faculty group with a water research focus. The authors have used information gained from this study to enhance collections and outreach at NMSU. This study also adds to the literature on citation analysis as a tool for informing collection development and management.  相似文献   

2.
Summary Voucher specimens ensure that the identity of organisms studied in the field or in laboratory experiments can be verified, and ensure that new species concepts can be applied to past research. Guidelines on the collection, preparation, and deposition of voucher specimens and means of referral to them are given. Type specimens and the nomenclature of species names are briefly described.Dedicated to the late Prof. Dr. W. Kühnelt  相似文献   

3.
In 1996 the assessment of tree condition in Italy was subjected to a Quality Assurance (QA) program. The QA program consisted in (i) the adoption of Standard Operating Procedures (SOPs), the set of Measurement Quality Objectives (MQOs) expressed by Data Quality Limits (DQLs), (iii) a national training and intercalibration course, and (iv) field checks, performed on a number of areas spread over the country. In general, DQLs were achieved for a number of tree condition indices. However, problems were identified with crown transparency, the most used index in the international reports. Additional problems arose when considering the data quality at plot level as a result of the combined achievement of DQLs for the different tree condition indices.  相似文献   

4.
As the sophistication and sensitivity of chemical instrumentation increase, so does the number of applications. Correspondingly, new questions and opportunities for systems previously studied also arise. As with most plants, the emission of volatiles from agricultural products is complex and varies among commodities. Volatiles are indicative of characteristics such as food quality, cultivar type, phenological stage, and biotic and abiotic stressors; thus, their systematic and accurate evaluation is important. Early volatile analyses entailed removal of the sample matrix in question, transport to the laboratory, and subsequent investigation. More recently, scientists are moving the laboratory to the field to obtain realistic emission patterns of the sample in its natural environment. This perspective proposes that a methodical and collaborative approach to the complex relationship between volatiles and agricultural commodities and their various phenological stages, oxidative degradation products, and fungal contamination is needed in order to fully comprehend the sample and associated relationships as a whole. These methodical approaches should incorporate both in situ and ex situ investigations of the sample. Ultimately, there exists an opportunity for development of methodologies that integrate both laboratory- and field-based collection of volatiles to explore and address the complex biological interactions of agricultural systems.  相似文献   

5.
ABSTRACT

A five year project to identify the most vital or core literature of the agricultural sciences was undertaken with results for the advanced countries as well as the Third World countries. Citation analysis and other bibliometric techniques were used to identify the most valuable literature for university-level instruction and research. Monographs in seven sub-disciplines of agriculture were evaluated by researchers resulting in a composite list of 8,400 volumes and in 363 core journals. Methods of analysis, evaluation techniques, and end products are described. Four of seven books describing the literature of agriculture have been published. A final product will be the transfer of the full text of the monographs and the journals for a five year period onto compact disk for use in the Third World. Because of copyright and other restrictions, the estimated 280 disk library will not be available to developed countries.  相似文献   

6.
The Electric Power Research Institute's (EPRI) Environmental and Health Sciences Business Unit, within the Environment Group, has initiated a multi-disciplinary applied research program to develop constructed wetland treatment systems as a cost-effective technology for the treatment of metal-bearing electric utility aqueous discharges. EPRI's program involves the building of constructed wetland treatment systems, collection of field data from these systems, and conduct of controlled laboratory experiments to more fully understand their functions and the factors affecting these functions. Both data collected through this program and existing data will be used to develop and deliver design criteria for the effective use of this technology to reduce or eliminate the risk that electric utilities will not meet regulatory-imposed effluent discharge limits. Currently, EPRI along with one of its members, is funding the construction of a state-of-the-art constructed wetland treatment system to treat a discharge from a closed dry ash management facility in Pennsylvania. This constructed wetland treatment system, along with existing ones located in California and Tennessee, will be used to collect data on the cycling of trace metals. Controlled laboratory experiments are underway to develop trace element uptake curves for wetland plant species, to determine which plant species one should plant in a wetland in a particular geographic area to maximize trace element removal. Plants also will be identified that are high volatilizers for selenium, arsenic and lead. As part of this research, the best plant/microbe associations (i.e., best plant species with the best microbe species) will be identified for achieving the highest rates of trace metal removal. Once this work is completed, these plants will be introduced into the three constructed wetland treatment systems mentioned above and the wetlands will be monitored to determine if any improvement in trace metal uptake is occurring. Additionally, EPRI is coordinating its research program with the Tennessee Valley Authority's (TVA) program, where design criteria for manganese rock drains for the removal of manganese and successive alkalinity-producing constructed wetlands for the treatment of acidic aerobic discharges will be developed. TVA is also supporting the development of EPRI's Wetland Environmental and Management (WEM) Model and is conducting research on anoxic limestone drains.  相似文献   

7.
Abstract

A computer data collection program requiring a minimum of program maintenance and technician training and allowing technician involvement with analytical instrument operation, was developed for a high volume production laboratory. The program, which complemented existing laboratory methodology, was written in top‐down, block‐style format. This structure insured easy maintenance and allowed individual instruments and their calibrations to be easily added to the program for data collection. The program was menu‐driven and limited direct technician involvement with instrument operation to changing samples, monitoring the instrument for calibration, monitoring the final readings, and intervening in the event of an obvious error. A two hour familiarization period requiring no instruction manuals was all that was required of a technician with no prior computer knowledge or training of any kind to become proficient with using the program.  相似文献   

8.
9.
A sorghum core collection representing a wide range of genetic diversity and used in the framework of a sorghum breeding and genetics program was evaluated by near-infrared reflectance spectroscopy (NIRS) to predict food grain quality traits: amylose content (AM), protein content (PR), lipid content (LI), endosperm texture (ET), and hardness (HD). A total of 278 sorghum samples were scanned as whole and ground grain to develop calibration equations. Laboratory analyses were performed on NIRS sample subsets that preserved the core collection racial distribution. Principal component analysis performed on NIRS spectra evidenced a level of structure following known sorghum races, which underlined the importance of using a wide range of genetic diversity. Performances of calibration equations were evaluated by the coefficient of determination, bias, standard error of laboratory (SEL), and ratio of performance deviation (RPD). Ground grain spectra gave better calibration equations than whole grain. PR equation (RPD of 5.7) can be used for quality control. ET, LI, and HD equations (RPD of 2.9, 2.6, and 2.6, respectively) can be used for screening steps. Even with a small SEL in whole sample analysis, a RPD of 1.8 for AM confirmed that this variable is not easy to predict with NIRS.  相似文献   

10.
Visible–near infrared (vis–NIR) spectroscopy can be used to estimate soil properties effectively using spectroscopic calibrations derived from data contained in spectroscopic databases. However, these calibrations cannot be used with proximally sensed (field) spectra because the spectra in these databases are recorded in the laboratory and are different to field spectra. Environmental factors, such as the amount of water in the soil, ambient light, temperature and the condition of the soil surface, cause the differences. Here, we investigated the use of direct standardization (DS) to remove those environmental factors from field spectra. We selected 104 sensing (sampling) sites from nine paddy fields in Zhejiang province, China. At each site, vis–NIR spectra were recorded with a portable spectrometer. The soils were also sampled to record their spectra under laboratory conditions and to measure their soil organic matter (SOM) content. The resulting data were divided into training and validation sets. A subset of the corresponding field and laboratory spectra in the training set (the transfer set) was used to derive the DS transfer matrix, which characterizes the differences between the field and laboratory spectra. Using DS, we transferred the field spectra of the validation samples so that they acquired the characteristics of spectra that were measured in the laboratory. A partial least squares regression (PLSR) of SOM on the laboratory spectra of the training set was then used to predict both the original field spectra and the DS‐transferred field spectra. The assessment statistics of the predictions were improved from R2 = 0.25 and RPD = 0.35 to R2 = 0.69 and RPD = 1.61. We also performed independent predictions of SOM on the DS‐transferred field spectra with a PLSR derived using the Chinese soil spectroscopic database (CSSD), which was developed in the laboratory. The R2 and RPD values of these predictions were 0.70 and 1.79, respectively. Predictions of SOM with the DS‐transferred field spectra were more accurate than those treated with external parameter orthogonalisation (EPO), and more accurate than predictions made by spiking. Our results show that DS can effectively account for the effects of water and environmental factors on field spectra and improve predictions of SOM. DS is conceptually straightforward and allows the use of calibrations made with laboratory‐measured spectra to predict soil properties from proximally sensed (field) spectra, without needing to recalibrate the models.  相似文献   

11.
树干茎流研究方法及其述评   总被引:14,自引:2,他引:14  
树干茎流研究是国内外森林水文学研究中的重要内容,对国内外树干茎流的研究方法及研究成果进行综述,并将树干茎流研究方法分为野外实测法和数学模型估测法,分别进行了系统分类和简要述评。树干茎流的野外实测法有观测标准株的选取与树干茎流水的收集两个关键技术环节。树干茎流的数学模型分为3种类型,即经验模型、概念模型、理论模型。经验模型反映的是树干茎流量(或茎流流率)与降雨量的定量关系,概念模型描述的是茎流量与降雨特征及林分特征因子的数量关系,理论模型刻画了树干茎流形成的机理和动态变化过程(树干茎流随降雨的时空变化规律),分别给出了各类模型主要的数学表达式,并分析了各类模型主要的优点和缺点。  相似文献   

12.
根据作者20多年从事奶牛胚胎移植研究与推广工作的实践,全面总结了我国奶牛胚胎移植和胚胎工程发展的历程及取得的主要成果,指出了目前存在的问题,提出了“十一五”重点研究领域。  相似文献   

13.
14.
We describe a raft designed to act both as a monitoring device and as a trap site for American mink, Mustela vison. The raft uses a wet tracking medium to record footprints. It was evaluated during summer in a chalk-stream river catchment in central southern England. The raft detected mink at significantly more sites (55%) than did either owners and managers relying on field observation and trapping (19%), or established biological survey techniques (33%).

The primary value of the raft is seen to be in experimental field research to determine appropriate policies for mink management. In the pilot application described, rafts were used to derive a minimum mink population estimate for the catchment, and to determine the benefit of a commercially available scent attractant for mink. The raft also has immediate value in management to improve several aspects of trapping for mink population control: efficiency, non-target involvement, and post-removal monitoring.  相似文献   


15.
This paper is an extensive review of the research that has been undertaken on near-infrared (NIR) and mid-infrared (MIR) spectroscopy applied to soil particularly for determining carbon (C) content. The objective is to determine which acquisition method (NIR, MIR, in the field or in the laboratory) might be recommended for the purpose of C stock measurement with a particular interest in carbon credit trading. For this purpose, an optimal method has to satisfy the dual constraints of low-cost and high throughput analysis. The various methods proposed in the literature are compared. In order to make comparisons as reliable as possible, special attention has been paid to the conditions of data acquisition (sample preparation), and to calibration and validation procedures. In particular, whether the validation has been carried out on fully independent samples or on samples similar to the ones of the calibration set greatly influences the results. Also, for C stock measurement, it is absolutely necessary to measure the bias of the prediction in order to be conclusive about the feasibility of the method. However, only few researchers provide this parameter and we recommend including it as a matter of course in future reports. Finally, although MIR on dried and ground samples is the most accurate method, on-the-go and in-field sensors provide predictions accurate enough to show promise in being a valuable component of technologies that would be used for C-credit purposes. But in order to meet the cost/accuracy trade-off, the main issue using such field sensors is to be able to simultaneously measure the bulk density or, better, to directly measure the volumetric concentration of C in soil. This circumvents the costs of field extraction and laboratory analysis. This is the next great challenge to be met by soil scientists.  相似文献   

16.
按照实验室测定油泥污染土壤等复杂介质样品中的多环芳烃分析要求,从消除背景干扰、提高测定数据质量出发,对样品前处理和仪器分析的各环节进行了系统的试验研究,建立了该类污染土壤中多环芳烃的气相色谱-质谱(GC-MS)测定方法,并对该方法进行了质量控制研究.结果表明:针对含油污泥污染土壤中的多环芳烃,该方法对16种多环芳烃的相关系数为0.999 3 ~ 0.999 7,各化合物线性关系良好;最低检出限为0.11 ~ 2.54 ng/ml;回收率为70.5%~107.0%;相对标准偏差为0.09% ~ 3.15%.本方法能够满足油泥污染土壤等复杂介质样品中的多环芳烃分析要求.  相似文献   

17.
面向土地精细平整的车载三维地形测量系统设计与实现   总被引:4,自引:3,他引:1  
设计开发了一种基于全地形车(ATV)的农田三维地形快速采集系统,系统由ATV车辆、RTK-GPS、田间作业辅助导航装置、车载计算机和数据采集软件等部分组成。采用高精度RTK-GPS自动测量三维地形数据,车载计算机能实时记录三维地形数据,辅助平行作业导航装置能指引数据采集车辆在测区进行全区域覆盖测量,以提高农田三维地形数据采集质量和效率。田间实测试验表明,基于ATV的三维地形数据自动采集系统测量的三维地形与人工RTK-GPS测量的三维地形与具有很好的空间一致性,最大平均偏差3.54 cm,最大标准偏差2.48 cm,能够满足农田土地精细平整三维地形数据采集工作的需要。  相似文献   

18.
Abstract

Nitrate remains a contaminant of concern for users of well water. Well‐water evaluation, either to assess nitrate contamination or to evaluate sites prior to including them in a larger water quality study, often involves costly laboratory analysis. A cost effective alternative to laboratory analysis are dip‐style test strips. However, the accuracy of these types of products must be reliable, as failure to identify the contaminant may, for example, persuade a homeowner to neglect to have a potential problem further investigated. The testing of nitrate using such strips typically involves dipping the strip into the water sample and reading the color development after a specific period of time. The color development is then compared to a color scale which corresponds to concentration provided with the test. The results of these types of analysis are especially open to interpretation by the evaluator of the results. An experiment was conducted to evaluate test strips in which individuals or “readers” tested water samples collected in the field and nitrate standards prepared in the laboratory with nitrate test strips. The results obtained by the “readers” were compared to analysis of nitrate by high performance liquid chromatography and colorimetric analysis using a colorimetric ion analyzer. There was a good agreement between the “readers” results and the analytical methodologies used. Use of the test strips by non‐technical persons, such as homeowners, could provide an accurate determination of nitrate in well water without the expense involved in a detailed laboratory analysis. The test strips can also be relied upon to accurately determine nitrate concentration when screening wells prior to designing field experiments.  相似文献   

19.
原位现场γ谱仪具有快速准确监测土壤中环境放射性核素137Cs和210Pbex的潜力,可以解决传统环境放射性核素示踪土壤侵蚀在选择参考点和测定时间过长问题。本研究应用现场γ谱仪(ISOCS,In-situObject Counting System),对内蒙古锡林浩特草原土壤中137Cs和210Pbex的含量进行了田间原位(不采样)测定,并与室内γ谱仪测定结果进行了比对。结果显示:现场γ谱仪的探头离地面1m,采用90度准直器,测量时间保证3600s以上时,测定的土壤中137Cs面积浓度与室内测定结果一致,二者的平均偏差为8%,表明现场γ谱仪测定具有较高精度,是快速评价土壤侵蚀速率的有效技术;210Pbex的原位测定结果显著高于室内测定结果,可能由于测定时间较短所致。初步研究结果表明:原位测定具有时间短、精度高的优点,可以克服传统采样造成的空间变异误差。  相似文献   

20.
淤地坝是黄土高原地区水土流失治理中行之有效的沟道治理措施,其通过滞洪拦泥淤地的方式在减沙减蚀方面发挥着至关重要的作用。随着流域生态保护的日趋科学合理,有必要对淤地坝在不同阶段的拦沙量进行定量准确分析,以评估其在水土流失治理中真实具体的效益,为黄河流域高质量发展的精准施策提供参考依据。通过查阅国内外淤地坝相关研究,结合野外调查采样、室内上机测试以及后续相关研究经验,系统总结归纳当前淤地坝拦沙量分析的实地调查、地形测绘法、数理归因法、成因分析法、权重系数法、模型模拟法和指纹识别技术7种方法,阐述各方法原理、步骤、适用性、需要解决的问题等,并对未来淤地坝拦沙量分析进行展望,以期能为进一步精准定量分析淤地坝拦沙量提供参考。  相似文献   

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