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Analysing changes in spatial point patterns:A proposal using data from a forest thinning experiment

Forest Ecosystems 2022年第6期9卷 878-887页

作者： Christian Salas-Eljatib Joaquín Riquelme-Alarcon Pablo J.Donoso Diego Ponce Daniel P.Soto Centro de Modelacion y Monitoreo de Ecosistemas Escuela de Ingeniería ForestalUniversidad MayorSantiagoChile Vicerrectoría de Investigacion y Postgrado Universidad de La FronteraTemucoChile departamento de Silvicultura y Conservacion de la Naturaleza Universidad de ChileSantiagoChile Instituto de Bosques y Sociedad Universidad Austral de ChileValdiviaChile Corporacion Nacional Forestal ValdiviaChile departamento de Ciencias Naturales y Tecnología Universidad de AysenCoyhaiqueChile

Spatial patterns reveal critical features at the individual and community levels.However,how to evaluate changes in spatial characteristics remains largely unexplored.We assess spatial changes in spatial point patterns by augmenting current statistical functions and indices.We fitted functions to describe unmarked and marked(tree size)spatial patterns using data from a large-scale silvicultural experiment in southern Chile.Furthermore,we compute the mingling index to represent spatial tree diversity.We proffer the pair correlation function difference before and after treatment to detect changes in the unmarked-point pattern of trees and the semivariogram-ratio to evaluate changes in the marked-point pattern.Our research provides a quantitative assessment of a critical aspect of forest heterogeneity:changes in spatial unmarked and marked-point patterns.The proposed approach can be a powerful tool for quantifying the impacts of disturbances and silvicultural treatments on spatial patterns in forest ecosystems.

关键词： Spatial diversity Marked-point process Spatial heterogeneity Conspecific Variable-density thinning Nothofagus

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Functional diversity in an Andean subparamo affected by wildfire in Colombia

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Plant Diversity 2023年第4期45卷 385-396页

作者： Korina Ocampo-Zuleta Angela Parrado-Rosselli Instituto de Ciencias Ambientales y Evolutivas.Facultad de Ciencias.Universidad Austral de Chile.Campus Isla Teja 5090000 ValdiviaChile Programa de Doctorado en Ciencias Mencion Ecología y Evolucion Escuela de GraduadosFacultad de CienciasUniversidad Austral de ChileValdiviaChile Jardín Botanico de Bogota Jose Celestino Mutis Subdireccion CientíficaLínea de Investigacion en Restauracion Ecologica111071BogotaColombia Facultad del Medio Ambiente y Recursos Naturales Universidad Distrital Francisco Jose de CaldasSede Vivero111711BogotaColombia

Recently,the Andean subparamo in Colombia has experienced severe wildfires,but little is known about the functional composition of recovering or not after a wildfire.Therefore,we examined the functional community composition subparamo affected byfire in 2016.We documented how functional traits changed 31 months after the disturbance and compared them with an unburned site.We sampled from one to two years after the fire every four months,then registered all recruits in 1655m plots.New individuals were classified into strategy functional groups based on the traits of persistence and dispersal.The first group was stem type and regeneration mechanism(seedling and resprout),and the second was fruit type and dispersal mode.We investigated the degree to which functional diversity changes plant communities over time(woody and non-woody),and we compared it with an unburned site.The most relevant results showed that resprouts and seed regenerated increased post-fire time and significant differences between sampling periods.The anemochory is the most relevant dispersal mode that indicates the community capacity to colonize the new gaps opened by the fire rapidly.We discuss how wildfire appears to be a triggering factor for persistence and dispersal strategy groups in subparamo burned given their characteristics of tolerance to stress.For this reason,a greater functional divergence between the ecosystems studied post-fire recovery has been related to higher levels of biodiversity at the landscape scale due to the high degree of endemism and significant differences in species composition between paramos.

关键词： Subparamo Cerro aguanoso Dispersal mode Functional traits Postfire regeneration

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Plant Nitrogen Metabolism: Balancing Resilience to Nutritional Stress andAbiotic Challenges

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 581-609页

作者： Muhammad Farhan Manda Sathish Rafia Kiran Aroosa Mushtaq Alaa Baazeem Ammarah Hasnain Fahad Hakim Syed Atif Hasan Naqvi Mustansar Mubeen yasir Iftikhar Aqleem Abbas Muhammad Zeeshan Hassan Mahmoud Moustafa department of Plant Pathology Faculty of Agricultural Sciences&TechnologyBahauddin Zakariya UniversityMultan60800Pakistan Centro de Investigación de Estudios Avanzados del Maule(CIEAM) Vicerrectoría de Investigación y PostgradoUniversidad Católica del MauleTalca3460000Chile College of Food Science and Nutritional Engineering China Agricultural UniversityBeijingChina department of Biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia department of Biotechnology Faculty of Biological SciencesLahore University of Biological and Applied SciencesLahorePakistan department of Plant Pathology College of AgricultureUniversity of SargodhaSargodha40100Pakistan department of Agriculture and Food Technology Karakorum International UniversityGilgitPakistan department of Biology Faculty of ScienceKing Khalid UniversityAbhaSaudi Arabia

Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen metabolism.This review explores nitrogen’s regulatory role in plant responses to these challenges,unveiling a dynamic interplay between nitrogen availability and abiotic stress.In the context of soil salinity,a nuanced rela-tionship emerges,featuring both antagonistic and synergistic interactions between salinity and nitrogen levels.Salinity-induced chlorophyll depletion in plants can be alleviated by optimal nitrogen supplementation;however,excessive nitrogen can exacerbate salinity stress.We delve into the complexities of this interaction and its agri-cultural implications.Nitrogen,a vital element within essential plant structures like chloroplasts,elicits diverse responses based on its availability.This review comprehensively examines manifestations of nitrogen deﬁciency and toxicity across various crop types,including cereals,vegetables,legumes,and fruits.Furthermore,we explore the broader consequences of nitrogen products,such as N_(2)O,NO_(2),and ammonia,on human health.Understand-ing the intricate relationship between nitrogen and salinity,especially chloride accumulation in nitrate-fed plants and sodium buildup in ammonium-fed plants,is pivotal for optimizing crop nitrogen management.However,prudent nitrogen use is essential,as overapplication can exacerbate nitrogen-related issues.Nitrogen Use Efﬁ-ciency(NUE)is of paramount importance in addressing salinity challenges and enhancing sustainable crop productivity.Achieving this goal requires advancements in crop varieties with efﬁcient nitrogen utilization,pre-cise timing and placement of nitrogen fertilizer application,and thoughtful nitrogen source selection to mitigate losses,particularly urea-based fertilizer volatilization.This review article delves into the multifaceted world of plant nitrogen metabolism and its pivotal role in enabling plant resilience to nutritional stress and abiotic challenges.It offers insights into future directions

关键词： Synthetic nitrogen nitrogen signaling sustainable agriculture eutrophication ammonium nitrate

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Characterization of Chemical Bath deposited CdSe Thin Films Doped with S^2-

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材料科学与工程（中英文B版） 2011年第5期1卷 657-666页

作者： Jorge Indalecio Contreras Rascon Oscar Portillo Moreno Gustavo Abarca Avila Jorge R. Cerna Juan Hernandez Tecorralco Javler Martinez Juare Rosendo Lozada Morales Orlando Zelaya Angel CIDS-ICUAP Benemerita Universidad Autonoma de Puebla 14 Sur y Av. Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexieo Facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla 14 Sur y Av. Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexico Facultad de Ciencias Fisicomatematicas postgrado en Optoelectroniea Benemerita Universidad Autonoma de Puebla 14 Sur y A v Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexico departamento de Fisiea del Centro de investigacion y de Estudios Avanzados del IPN 07360 Mexico D. F. Mexico

CdSe thin films doped with S2-, growing on glass substrates using the chemical bath deposition (CBD) at temperature of T = 80 oC, with precursor solutions: CdCl2 0.01 M, KOH 0.1 M, 0.5 M, SeC(NH2)2 0.04 M, NH4NO3, SC(NH2)2 0.2 M, 5, 10, 15, 20, 25 and 30 mL of doping. The concentration of atoms was obtained by Scanning Electron Microscopy (SEM), S = 14.11-42.57, Cd = 49.11-59.59, and Se = 50.99-2.29, X-ray diffraction, identifies mixture of Wurzite/Zinc blende doped films phases and size of grain of 24-15 nm. Optical Absorption Spectra have redshifts of the forbidden band gap (Eg) of 1.8-2.3 eV. Raman spectra (RS) show the Raman shift, confirming formation of nanocrystals. From the dark conductivity vs. 1/kT behavior on the 100-500 K range, attributed to doping effects at the grain boundaries and quantum confinements. A thermodynamic model is proposed using the equation of Nernst to evaluate changes in the Gibbs free energy and investigate the spontaneity of reactions.

关键词：硒化镉薄膜化学浴沉积掺杂效应 CdSe 扫描电子显微镜 X射线衍射分析表征吉布斯自由能

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Characterization of Chemical Bath deposited CdS, CdSe and PbS

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材料科学与工程（中英文A版） 2011年第5X期1卷 692-704页

作者： Oscar Portillo Moreno Gustavo Abarca Avila Jorge R. Cerna Juan Hernandez Tecorralco Melissa Chavez Portillo Javier Martinez Juarez Rosendo Lozada Morales Orlando Zelaya Angel Facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla Mexico Col. Sn. Manuel Puebla Pue. Mexico CIDS-ICUAP Benemerita Universidad Autonoma de Puebla Mexico. Col. Sn. Manuel Puebla Pue. Mexico Fac. Ciencias Fisicomatematicas Postgrado en Optoelectronica Benemerita Universidad Autonoma de Puebla Mexico Col. Sn Manuel Puebla Pue. Mexico departamento de Fisica Centro de investigacion y de Estudios de Estudios Avanzados del IPN 07360 Mexico D. F. Mexico

CdS, CdSe and PbS films were grown onto glass by chemical bath deposition (CBD). Different constant deposition temperatures (Td) were employed in the range 0-80 °C with subintervals of 10 °C. Concentration of reagents, pH, and stirring were maintained constants. A microcrystalline mixture CdCO3 and CdS were grown. At intermediates Td values a mixture of both materials present. i. e., For Td? 40 °C, the intensity of the main of X-ray Diffraction (XRD) CdS peak is abruptly reduced. By scanning electronic microscopy (SEM) with Td = 80 °C, concentration atomic: Cd = 49.10, S = 51.90, for Td? 70 °C, increase of carbon and oxygen. The CdSe, average grain size (GS) increased monotonic with Td, reaching saturation of 70 °C, with GS values of 5-16 nm. At low Td values (0-20 °C), the structural phase was found, and the high Td = 70 °C on material 5-16 nm was appreciated transition to phase: Wurzite (W)? Zinbclende (ZB) and phases mixture: W/ZB, grain size (GS) 9-27 nm. By (XRD), PbS grow in W phase at all films, for Td = 60 °C, was observed preferential orientation in plane [111] with (GS) of 19-26 nm also a Gibbs free energy calculation is included.

关键词： CdSe 化学浴沉积 PBS 平均晶粒尺寸扫描电子显微镜表征吉布斯自由能薄膜生长

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委内瑞拉产绿散胞盘菌属一新种(英文)

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菌物学报 2013年第3期32卷 457-461页

作者： ITURRIAGA Teresa MARDONES Melissa Laboratorio de Micología Departamento de Biología de Organismos Universidad Simón Bolívar Baruta Edo. Miranda Venezuela

从El Avila国家公园热带云雾森林中发现了绿散胞盘菌属的一个新种。它以其小型的子囊和子囊孢子、椭圆-S型-棒状的子囊孢子以及覆盖于外囊盘被菌丝表面的绿褐色胶化层为显著特征,并与该属已知种相区别。

关键词：盘菌新热带区分类

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