检索结果-南通市图书馆

Morphometry and Mineral Content in the Seeds and Soil of Two Species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert

引用

Phyton-International Journal of Experimental Botany 2024年第2期93卷 371-386页

作者： Perla Patricia Ochoa-García Jaime Sánchez-Salas Ricardo Trejo-Calzada Jesús JosafathQuezada-Rivera Fabián García-González Unidad Regional Universitaria de ZonasÁridas BermejilloUniversidad Autónoma ChapingoDurango35230México Facultad de Ciencias Biológicas Universidad Juárez del Estado de DurangoGómez PalacioDurango35010México

The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical interest.They are inedible plants considered as scrubs.To date they have not been broadly studied;thus,their ecology is,to our knowledge,unknown.The present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in Mexico.In April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the CD.The seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were determined.The soil samples were obtained under the Mexican regulation NOM-021-RECNAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were performed.The information obtained was grouped by variable,species,and place of precedence.The statistical tests consisted of an ANOVA,Tukey means tests considering p≤0.05,and a Principal Components Analysis.Argemone pleiacantha exhibited differences in terms of weight(F=54.79,p=0.001),length(F=90.83,p=0.001),thickness(F=104.89,p=0.001),and diameter(F=155.82,p=0.001),and the differences in Argemone mexicana were in weight(F=46.71,p=0.001),thickness(F=187.49,p=0.001),length(F=191.56,p=0.001),and diameter(F=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of evaluation.The content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds.

关键词： Micronutrients agricultural area semiarid zone ecoregion buoyancy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An Artificial Neural Network Model to Analyze Maize Price Behavior in Mexico

引用

Applied Mathematics 2018年第5期9卷 473-487页

作者： Raquel Salazar Moreno Oscar Zerecero Salazar universidad autó noma chapingo Texcoco Mexico

Mexican producers were supported by the Government from 1993-2013 through the PROCAMPO (support program, direct subsidy from the federal government), in order to keep the prices stable. The tool used to analyze the basic products price behavior was Artificial Neural Network (ANN) models. Data from the period 1980 to 2014 was available, and two ANN models were implemented, one including only internal prices of related products and the second takes into account also the international maize price. The purpose of this paper was to analyze the impact of internal related products and international maize price on the behavior of internal maize price. Both models demonstrated the powerful of the ANN for prediction of the maize price 3 and 5 years ahead. Also, a sensitivity analysis was performed using Garson’s algorithm, through which was demonstrated that rice, safflower and sorghum are corn’s complementary products. The rice price was the variable with a major positive impact on the national corn price. On the other hand, wheat, soybean and barley behave as corn’s substitute products, with wheat price being the variable with major impact on the corn price. Including the international corn price improves the model performance, besides there was a negative sensitivity between the international and national corn price;this behavior is explained by the fact that during PROCAMPO existence, the national prices were forced to be stable while the international maize price was increasing. Finally, this study showed the application of the ANN models in a particular product price behavior, with the possibility of being used in the decision making process for the application of subsidies to the agricultural producers in public policies.

关键词： PROCAMPO Prediction Sensitivity Analysis Policy Impact

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pb and Cr Content in an Agricultural Soil Irrigated with Wastewater and Their Bioaccumulation in Alfalfa

引用

Journal of Geoscience and Environment Protection 2023年第11期11卷 116-128页

作者： Victor Manuel Duarte Zaragoza Lozano-Camargo Maria Luisa Carrasco Hernández Violeta Pérez Hernández Victoria Sabrina División de Ingeniería Ambiental Tecnológico de Estudios Superiores del Oriente del Estado de México La Paz México Departamento de Ciencias Forestales Universidad Autónoma de Chapingo Texcoco México Facultad de Ciencias del Mar Universidad Autónoma de Sinaloa Mazatlán Sinaloa México

Urban wastewater contains various pollutants, with heavy metals being common, posing risks to the environment and public health, especially when used for irrigation in agricultural systems. This study aimed to assess the total and bioavailable content of Pb and Cr in agricultural soil irrigated with wastewater and their accumulation in alfalfa crops. Five alfalfa sites were sampled, and ten surface soil samples were collected from the top 30 cm of each plot. Plant samples were also collected at each sampling point. A composite sample of irrigation water from the main channels was also collected and prepared. The concentration of heavy metals was determined using atomic absorption spectrophotometry. The results revealed concentrations of Pb and Cr (VI) in the irrigation water above the maximum permissible limits according to environmental regulations. The soil had high organic matter content, neutral pH, elevated electrical conductivity (EC), and Pb and Cr contents of up to 103 and 89 mg/kg, respectively. In alfalfa tissues, Pb and Cr concentrations were recorded at 26 mg/kg and 4.6 mg/kg, respectively (Cr (VI), with lower concentrations observed in the roots. Cr (VI) was higher at all sites, with ranges from 2.25 to 43.56, while lead (Pb) had an AR ranging from 0.64 to 27.04. The Pb presented a mean of 1.45 of the Bioaccumulation factor values, which can be considered a metal-accumulating plant.

关键词： Heavy Metals Bioavailability Lead Bioaccumulation Factor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photovoltaic Prickle Pear Harvesting Tool

引用

Natural Resources 2013年第3期4卷 263-265页

作者： Federico Hahn Departamento Irrigación Universidad Autónoma Chapingo Chapingo México.

Mexico is the largest cactus exporter of the world and 40% of the production cost is provided from the harvest operation. Many workers are required to operate daily and suffer wrist pain after two weeks of collecting pears with mechanical pruners. A motor driven tool supplied from a photovoltaic system was employed for harvesting;different blades were tested at different cutting speeds. It was found that toothed blades sliced the pears with efficiencies over 90%. Abrasive blades were finally selected as the current required per cut was minimum, permitting a longer battery lifetime before requiring recharging.

关键词： Prickle Pear Harvesting Tool Current Integral

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparative Analysis of Biogas Estimation Models versus <i>In-Situ</i>Measurement in a Landfill Site in the State of Mexico, Mexico

引用

Journal of Environmental Protection 2017年第12期8卷 1460-1473页

作者： Pablo Emilio Escamilla-García María Elena Tavera-Cortés Francisco Pérez-Soto universidad autónoma chapingo Chapingo México Instituto Politécnico Nacional Mexico City Mexico

This paper shows a comparative analysis of theoretical model for biogas estimations in landfill sites in order to determine reliability, accuracy and efficiency by comparing results with actual data obtained in-situ. The model from the Environmental Protection Agency (EPA) and the Mexican model were selected to estimate biogas generation in a landfill site located in the State of Mexico, Mexico with 36 wells. Both models are based on a first order equation for degradation of organic matter assuming that the biogas generation reaches its maximum after a period of time and then biogas generation decreases exponentially while the organic fraction of waste is consumed. Measurement in-situ, using a landfill gas analyser (GA5000), resulted in values of percentage concentration of landfill gas (CH4, CO2 and O2) with an average Frequency of 35.44 Hz (1/s) and emissions of methane of 3355.99 m3/hr in contrast with 4885.74 m3/hr from EPA model and 6780.56 m3/hr from Mexican model. The experiment evidenced significant variations in estimations versus actual measurements. authors discuss the aspects and parameters that cause such variations in order to provide a comprehensive analysis which will help decision makers to base waste management strategies in Mexico on reliable data.

关键词： Biogas Methane Landfill Gas Estimation Models

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evaluation of Ocimum basilicum L.with Different Concentrations of K^(+)as an Inhibitor of Pathogenic Bacterial Strains

引用

Phyton-International Journal of Experimental Botany 2021年第2期90卷 533-541页

作者： Mercedes Georgina Ramírez-Aragón Victoria Jared Borroel-García Ramón Valenzuela-Soto Ricardo David Valdez-Cepeda Francisco Javier Wong-Corral JoséLuis García-Hernández universidad Politécnica de Gómez Palacio Gómez Palacio35120México universidad autónoma chapingo Centro Regional Universitario Centro-NorteZacatecasZac.Universidad Autónoma de ZacatecasFacultad de MatemáticasZacatecas98053México Departamento de Investigación y Posgrado en Alimentos Universidad de SonoraHermosillo83000México Facultad de Agricultura y Zootecnia Universidad Juárez del Estado de DurangoGómez Palacio34000México

The extraction of bioactive compounds has become one of the most interesting areas of modern chemistry.For therapeutic reasons,it´s important to obtain antimicrobial agents from natural origin.The objective of the present study was to determine the inhibitory effect of ethanolic extract of basil(Ocimum basilicum L.var.Red Rubin)subjected to different concentrations of potassium(K^(+))on the activity of three bacterial strains that are pathogens in humans.Susceptibility was evaluated by inhibition surface and these results were compared to two antibiotics:Gentamicin(GE)and Ciprofloxacin(CPF)for their efficacy against each bacterial strain.Analyzed variables presented significant difference(p≤0.05).According to the results,basil extract evaluated showed positive antibacterial activity against the three strains of Pseudomonas aeruginosa,Listeria monocytogenes and Staphylococcus aureus on Mueller Hinton agar.It was observed highest inhibition areas of different diameters(15.3 mm,21.3 mm and 21.6 mm respectively)when the extract used was obtained from the plants with the highest concentration of potassium(13 mmol L-1).These values were even superior to the highest values showed on the treatments with the antibiotic gentamicin.

关键词： Basil inhibition potassium secondary metabolites antibiotics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Drought and Spatiotemporal Variability of Forest Fires Across Mexico

引用

Chinese Geographical Science 2018年第1期28卷 25-37页

作者： Pompa-García MARíN Camarero J.JULIO Rodríguez-Trejo DANTE ARTURO Vega-Nieva DANIEL JOSE Facultad de Ciencias Forestales Universidad Juarez del Estado de Durango Durango 34120 MExico Instituto Pirenaico de Ecologia IPE-CSIC 50059 Spain Divisian de Ciencias Forestales Universidad Autonoma Chapingo Chapingo 56230 MExico

Understanding the spatiotemporal links between drought and forest fire occurrence is crucial for improving decision-making in fire management under current and future climatic conditions. We quantified forest fire activity in Mexico using georeferenced fire records for the period of 2005–2015 and examined its spatial and temporal relationships with a multiscalar drought index, the Standardized Precipitation-Evapotranspiration Index(SPEI). A total of 47975 fire counts were recorded in the 11-year long study period, with the peak in fire frequency occurring in 2011. We identified four fire clusters, i.e., regions where there is a high density of fire records in Mexico using the Getis-Ord G spatial statistic. Then, we examined fire frequency data in the clustered regions and assessed how fire activity related to the SPEI for the entire study period and also for the year 2011. Associations between the SPEI and fire frequency varied across Mexico and fire-SPEI relationships also varied across the months of major fire occurrence and related SPEI temporal scales. In particular, in the two fire clusters located in northern Mexico(Chihuahua, northern Baja California), drier conditions over the previous 5 months triggered fire occurrence. In contrast, we did not observe a significant relationship between drought severity and fire frequency in the central Mexico cluster, which exhibited the highest fire frequency. We also found moderate fire-drought associations in the cluster situated in the tropical southern Chiapas where agriculture activities are the main causes of forest fire occurrence. These results are useful for improving our understanding of the spatiotemporal patterns of fire occurrence as related to drought severity in megadiverse countries hosting many forest types as Mexico.

关键词：空间统计墨西哥干旱时间土壤水分蒸发蒸腾损失总量可变性加利福尼亚森林火

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Assessing the Performance of Two Hydrologic Models for Forecasting Daily Streamflows in the Cazones River Basin (Mexico)

引用

Open Journal of Modern Hydrology 2016年第3期6卷 168-181页

作者： Fernando González-Leiva Rodrigo Valdés-Pineda Juan B. Valdés Laura A. Ibáñez-Castillo Posgrado en Ingeniería Agrícola y Uso Integral del Agua Universidad Autónoma Chapingo Chapingo México Department of Hydrology and Water Resources University of Arizona Tucson AZ USA

Floods have caused significant human and economic losses in the Cazones River Basin, located on the Gulf of Mexico. Despite this knowledge, steps towards the design and implementation of an early warning system for the Cazones are still a pending task. In this study we contributed by establishing a hydrological scheme for forecasting mean daily discharges in the Cazones Basin. For these purposes, we calibrated, validated and compared the HyMod model (HM) which is physics-based, and an autoregressive-based model coupled with the Discrete Kalman Filter (ARX-DKF). The ability of both models to accurately predict discharges proved satisfactory results during the validation period with RMSEHYMOD = 2.77 [mm/day];and RMSEARX-DKF = [2.38 mm/day]. Further analysis based on a Streamflow Assimilation Ratio (SAR) revealed that both models underestimate the discharges in a similar proportion. This evaluation also showed that, under the most common conditions, the simpler stochastic model (ARX-DKF) performs better;however, under extreme hydrological conditions the deterministic HM model reveals a better performance. These results are discussed under the context of future applications and additional requirements needed to implement an early warning hydrologic system for the Cazones Basin.

关键词： Hydrologic Models Cazones Basin HyMod Discrete Kalman Filter Hydrologic Uncertainty

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Distribution of Prunus serotina Ehrh. in North America and Its Invasion in Europe

引用

Journal of Geoscience and Environment Protection 2018年第9期6卷 111-124页

作者： Sergio Segura Félix Guzmán-Díaz Javier López-Upton Catherine Mathuriau Jósé López-Medina Centro Regional Universitario Centro Occidente-universidad autónoma chapingo Morelia México IH-universidad autonoma chapingo Chapingo México Instituto Recursos Naturales Colegio de Postgraduados Montecillos México Freelance Researcher Lyon France Facultad Agrobiología-universidad Michoacana de San Nicolás de Hidalgo Uruapan México

Black cherry (Prunus serotina Ehrh.) is a native North American plant species. It includes five subspecies and is currently invasive in Europe. Since pre-Hispanic times, black cherry has been known and used by American inhabitants, and its botanical use was reported in the 19th century. The present study describes the taxonomic richness and taxonomic diversity of the species based on data from 554 taxonomically confirmed collection sites. Additionally, 19 climatic parameters were used to estimate the current and future potential distribution patterns of black cherry applying a climate change model to North America and Europe. Regions of northeast Mexico, northwestern Mexico, the Great American Basin, and the Mississippi River-Great Lakes region in the USA are shown as areas where taxa of P. serotina are present. The potential distribution model of black cherry in North America shows a continuous pattern starting in the Center of Mexico and following both main Mexican mountain ranges (Sierra Madre Oriental and Sierra Madre Occidental). The pattern extends following two different paths throughout northern Mexico toward the Rocky Mountains and the Appalachians in the USA. Based on the NOAA-CCM3 climatic change model, decreased rainfall in wetlands will result in changes in future patterns in America. When applied to Europe, our model shows more extensive regions and more accurately than previous estimations;thus, the current potential distribution of the species includes important areas in the western part of the continent. The potential effect of climate change on P. serotina distribution suggests new and wider areas of possible invasion of this species throughout the continent mainly in France, Germany, and Italy. We suggest take into account the whole American taxa included in this species in the end to study its potential invasion in Europe and establishing suitable control strategies.

关键词： Black Cherry Taxonomic Richness Taxonomic Diversity Invasion Climate Change

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Design of a Methane Monitoring System for Landfill and Duct Emissions

引用

Natural Resources 2020年第11期11卷 520-529页

作者： Federico Hahn Gaudencio Grande Irrigation Department Universidad Autonoma Chapingo Texcoco México IAUIA Universidad Autonoma Chapingo Texcoco México

Methane is released from waste disposal areas as a result from anaerobic decay of food. Methane causes more greenhouse effects than carbon dioxide so a methane monitoring system is required to warn its release from gas emitting environments. The low explosive limit of methane is 5% in ambient air, so gas leakage is dangerous and can produce explosions. An entire head monitoring system was built around a MQ-4 methane gas sensor as it is cheap and reliable. The design proves to be flexible enough as it can measure CH4 emissions in ducts, CH4 in landfills at different depths and even in cattle barns. The measuring system head consists of a suction pump, solenoids, and a methane sensor. Measurements are taken 13 seconds after methane gas sucking. A timing of 100 seconds is required for purging the chamber before the second solenoid is turned-on. Devices temperature during operation was sampled with a thermal Flir-One camera and solenoid coil temperature was of 24.9˚C after a continuous operation of 30 seconds. As hoses for emission sampling become larger time for sampling increases as well as energy consumption.

关键词： Methane Detection MQ-4 Sensor Monitoring Head Current Consumption

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：