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Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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林业研究:英文版 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-Salazar Marcela Rosas-Chavoya Marín Pompa-García Pablito Marcelo López-Serrano emily García-Montiel Arnulfo Meléndez-Soto Sergio Iván Jiménez-Jiménez instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico instituto de silvicultura e industria de la madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-CeNID RASPA Centro Nacional de Investigación Disciplinaria en Relación Agua-Suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal versatility.UAV with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of vegetation.This study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one year.The study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea coexist.Multispectral images were acquired with UAV and information on meteorological variables was obtained from NASA/POWeR database.An ANOVA explored possible differences in NDVI among the three species.Pearson correlation was performed to identify the linear relationship between NDVI and meteorological variables.Significant differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their phenology.Quercus grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and temperatures.Although the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

Variable-top stem biomass equations at tree-level generated by a simultaneous density-integral system for second growth forests of roble, raulí,and coigüe in Chile

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Journal of Forestry Research 2019年第3期30卷 993-1010页

作者： Carlos Valenzuela eduardo Acuna Alicia Ortega Geronimo Quinonez-Barraza Jose Corral-Rivas Jorge Cancino departamento Manejo de Bosques y Medio Ambiente Facultad de Ciencias ForestalesUniversidad de Concepcion Victoria 631Barrio Universitario4070386 ConcepcionChile instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austral de ChileCampus Isla Teja5110566 ValdiviaChile Campo experimental Valle del Guadiana Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias (INIFAP)km 4.5 Carretera Durango-Mezquital34170 DurangoDGOMexico instituto de silvicultura e industria de la madera Universidad de Juarez del Estado de Durango34120 DurangoMexico

Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral system, which combines a stem taper model and a wood basic density model. For each model, an autoregressive structure of order 2 and a power equation of residual variance were incorporated to reduce residual autocorrelation and heteroscedasticity, respectively. By using dummy variables in the regression analysis, zonal effects on the parameters in the variable-top stem biomass equations were detected in roble. Consequently, equations for clusters of zones were obtained. These equations presented significant parameters and a high precision in both fitting and validation processes (i.e., CVespectively), demonstrating that they are unbiased. The advantage of these types of functions is that they provide estimates of volume and biomass of sections of the stem, defined between any two points of the stem in the three species. Thus, depending on the final use of the wood and the dimensions of the tree, a stem fraction can be quantified in units of volume and the remaining fraction in units of weight.

关键词： Autocorrelation density-integral Dummy variables Autoregressive error structure Heteroscedasticity

Abiotic and biotic drivers of struvite solubilization in contrasting soils

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Pedosphere 2023年第6期33卷 828-837页

作者： Antonio RUIZ-NAVARRO Manuel deLGADO-BAQUeRIZO Concha CANO-DíAZ Carlos GARCíA Felipe BASTIDA Centro de edafologia y Biologia Aplicada del Segura Consejo Superior de Investigaciones Cientificas(CEBAS-CSIC)Department of Soil and Water ConservationEspinardoMurcia E-30100Spain ICL Specialty Fertilizers Iberia TotanaMurcia E-30850Spain laboratorio de Biodiversidad y Funcionamiento ecosistemico Instituto de Recursos Naturales y Agrobiologia de Sevilla(IRNAS)CSICAv.Reina Mercedes 10Sevilla E-41012Spain IRNAS-CSIC Unidad Asociada Universidad Pablo de OlavideUniversidad Pablo de Olavide(UPO)Sevilla 41013Spain Centre for Research and development in Agrifood Systems and Sustainability(CISAS) Instituto Politecnico de Viana do Castelo(IPVC)Rua Escola Industrial e Comercial Nun'Alvares 34Viana do Castelo 4900-347Portugal

Phosphorus(P) limitation in the coming decades calls for the utilization of alternative fertilizers in agriculture. Struvite is a promising P source, but its potential role as a fertilizer is dependent on different physical, chemical, and biological properties, which are very heterogeneous in soil, complicating the prediction of the best soil conditions for its application. Here, we evaluated the solubility of struvite in soil, its redistribution into P fractions, and its potential abiotic and biotic drivers in 62 globally distributed soils with contrasting properties through an incubation assay. We found that after 40 d, about 35% of struvite P was redistributed into soil fractions more accessible to plants and microbes. Phosphorus redistribution from struvite was driven by a complex suite of soil physical, chemical, and microbial properties as well as environmental factors that varied across soils. Soil texture played a critical role in determining the redistribution of P in struvite-amended soils in soluble(H2O extraction), labile(NaHCO3 extraction), and moderately labile(NaOH extraction) fractions.In addition, the soil solution cation concentration was one of the most important drivers of available struvite-derived P fractions. The great importance of texture and cations in determining struvite-derived P fractions in soil was contrasted with the relatively minor role of pH. At the microbial level, the number of bacterial operational taxonomic units(OTUs) from the unfertilized soils that correlated with struvite-derived P fractions was higher than that of fungi. The number of OTUs that correlated with the struvite-derived soluble P fraction was dominated by fungi, whereas the number of OTUs that correlated with the struvite-derived labile P fraction was dominated by bacteria. Overall, this study provided a predictive framework for the potential use of struvite as a P fertilizer in contrasting soils.

关键词： bacteria fungi environmental factor operational taxonomic unit phosphorus fertilizer phosphorus fraction phosphorus solubilization soil fertility soil property

Association of <i>Ammodramus bairdii</i>A. 1844, and Other Species of Grassland Granivorous Birds in Winter Time in Northwestern Mexico

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Open Journal of ecology 2014年第5期4卷 281-288页

作者： Jose Hugo Martinez-Guerrero Martin emilio Pereda-Solis Christian Wehenkel Facultad de MedicinaVeterinaria y Zootecnia. Universidad Juarez del estado de Durango Durango Mexico instituto de silvicultura e industria de la madera Universidad Juarez del Estado de Durango Durango Mexico

During the winter of 2009 grassland birds were monitored in the region of Cuchillas de la Zarca to estimate the association betweenAmmodramus bairdiiAudubon 1844, focal species of grassland and bird species belonging to the trophic guild of grassland granivorous birds (n = 25 ). The study area was divided into monitoring quadrants (n = 16) where 96 transects for bird monitoring were conducted, recording 16,635 individuals of which only 32.9% were in the trophic guild of grassland granivorous birds. The association betweenA. bairdiiand other species was estimated from the nonparametric statistical index of Kendall’s coefficient of concordance (W) and the p value, through permutation analysis (n = 10,000), finding positive and significant associations (p≤0.05) of the target species for study withSturnella magna,Passerculus sandwichensisandAmmodramus savannarum, species that share habitat preferences of natural grassland in good condition, slightly grazed and with little tolerance to the shrub cover. The association W ranged from 0.072 and 0.749. These results can recognize this region as an important area for the conservation of obligate grassland birds during winter, suggesting establish training programs to better utilize this resource by means of cattle activity.

关键词： Grassland Birds Kendall Coefficient Baird’s Sparrow Winter Monitoring

Local and generalized height-diameter models with random parameters for mixed,uneven-aged forests in Northwestern Durango,Mexico

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Forestry Studies in China 2014年第1期16卷 41-49页

作者： Sacramento Corral-Rivas Juan Gabriel lvarez-González Felipe Crecente-Campo José Javier Corral-Rivas instituto Tecnológico de eI Salto Mesa del Tecnologico s/n.Apdo.Postal No.2EI Salto P.N.34950DurangoMéxico departamento de Ingenieria Agroforestal Universidad de Santiago de Compostela.Escuela Politécnica SuperiorCampus Universitario27002 LugoEspana lnstituto de silvicultura e industria de la madera Universidad Jurez del Estado de DurangoBlvd.del Guadiana # 501.Cuidad Universitaria34160 DurangoMexico

Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variables as predictors.Methods:The data were obtained from 44 permanent plots used to monitor stand growth under forest management in the study area.Results:The generalized Bertalanffy-Richards model performed better than the other generalized models in predicting the total height of the species under study.For the genera Pinus and Quercus,the models were successfully calibrated by measuring the height of a subsample of three randomly selected trees close to the mean d,whereas for species of the genera Cupressus,Arbutus and Alnus,three trees were also selected,but they are specifically the maximum,minimum and mean d trees.Conclusions:The presented equations represent a new tool for the evaluation and management of natural forest in the region.

关键词： Conifer and broadleaves forests h-d relationship Mixed models Calibration

Geospatial Model as Strategy to Prevent Forest Fires: A Case Study

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Journal of environmental Protection 2012年第9期3卷 1034-1038页

作者： Marín Pompa-García Maico Zapata-Molina Ciro Hernández-Díaz efraín Rodríguez-Téllez Facultad de Ciencias Forestales Universidad Juárez del Estado de Durango (UJED) Victoria de Durango México instituto de silvicultura e industria de la madera Universidad Juárez del Estado de Durango (UJED) Victoria de Durango México

The forests of the State of Durango have been severely affected by fires in recent years. early detection of fires through watchtowers is essential. In this work a geospatial model was generated to optimize strategic visualization points, using a GIS environment. Analysis of the area of visibility was developed by integrating a digital model of elevation and a plant cover map. The resulting distribution generates more than 50% coverage of the studied area, in points that were not always the highest. It was concluded that this strategy would permit to increase the efficiency, mainly favoring the communities of pine, whose economic importance would justify the required investment.

关键词： Viewshed Analysis Watchtowers Forest Fires

Natural durability of wood of ten native species from northeastern Mexico

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Forestry Studies in China 2013年第2期15卷 160-166页

作者： Artemio CARRILLO Rahim FOROUGHBACHK Verónica BUSTAMANTe Christian WeHeNKeL Humberto GONZáLeZ Universidad Autónoma de Nuevo León (UANL) Facultad de Ciencias ForestalesCarr. Nal. No. 85 Km 145. 66700 041. Linares Nuevo León México Universidad Autónoma de Nuevo León (UANL) Facultad de Ciencias Biológicas San Nicolás de los GarzaNuevo León 66451 México instituto de silvicultura e industria de la madera Universidad Juárez del Estado de DurangoKm 5.5 Carretera Mazatlán 34120 Durango México

Thorn scrub vegetation in Mexico is distributed over 50 million ha, where native tree species are the source of forage, timber, firewood and charcoal. Research describing wood durability of species from this vegetation type has not been fully determined, nor classified according to international standards. Thus, the aim of this study was to determine and classify the natural durability of ten woody species. Their natural durability was determined according to the european Pre-Norm 807, the loss of dynamic modulus of elasticity （MOedyo）（MPa） was determined and wood mass loss （g） after being exposed to Trametes versicolor and Coniophora puteana fungi. Wood durability was classified accord- ing to the european Norm 350-1. Highly significant differences （p 〈 0.001） were found between the durability of woody species. The more durable species with lower MOedyn lost were Condalia hooked （57.5% ± 0.6%）, Havardia pallens （58.2% ± 0.4%） and Acacia schaffneri （58.9% ±6.3%）. Species with lower mass loss after exposed to Coniophora puteana were ebenopsis ebano （6.3% ±1.9%）, Condalia hooked （8.6% ±2.3%） and Cordia boissieri （11.8% ±2.3%）. e. ebano （7.1% ±2.4%）, Condalia hooked （8.2% ± 2.5%） and Cordia boissieri （11.5% ± 3.1%） showed the lower mass lost after exposed to T. versicolor. According to european Norm 350-1, three woody species were classified as very durable and durable species.

关键词： native species natural durability dynamic modulus of elasticity mass loss

Suitable conditions for natural regeneration in variable retention harvesting of southern Patagonian Nothofagus pumilio forests

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ecological Processes 2019年第1期8卷 240-251页

作者： Mónica D.R.Toro Manríquez Juan M.Cellini María V.Lencinas Pablo L.Peri Karen A.Peña Rojas Guillermo J.Martínez Pastur Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina laboratorio de Investigaciones en maderas(LIMAD) Universidad Nacional de la Plata(UNLP)Diagonal 113 n°469(1904)La PlataBuenos AiresArgentina instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina departamento de silvicultura y Conservación de la Naturaleza Facultad de Ciencias Forestales y de Conservación de la NaturalezaUniversidad de Chilecc 9206SantiagoChile.

Background:Variable retention(aggregated and dispersed retention)harvesting proposed for Nothofagus pumilio was designed for timber purposes and biodiversity conservation.Harvesting by opening canopy generates different microenvironments and creates contrasting conditions for seedling establishment,growth,and eco-physiology performance due to synergies(positives or negatives)with biotic and abiotic factors.This study evaluated the regeneration in different microenvironment conditions within managed stands during 5 years after harvesting.Remnant forest structure after harvesting and different microenvironments were characterized in managed stands,where 105 regeneration plots were measured(3 stands×7 microenvironments×5 replicas).We characterized the seedling bank,as well as growth and ecophysiology performance of the regeneration.Univariate and multivariate analyses were conducted for the comparisons.Results:Microenvironments offered different environmental conditions for natural regeneration(soil moisture and light availability).Seedling under debris and dicot plants showed better eco-physiological performance,establishment,and growth than plants growing under monocots or located in the dispersed retention without the protection of other understory plants.The most unfavorable microenvironment conditions were high canopy cover of remnant trees(inside the aggregates or close to trees in the dispersed retention)and heavily impacted areas(skidder extraction roads).Conclusions:Favorable microenvironments in the harvested areas will improve the natural recruitment,growth,and eco-physiology performance of the natural regeneration after harvesting.It is necessary to develop new silvicultural practices that decrease the unfavorable microenvironments(e.g.,road density or excessive woody accumulation),to assure the success of the proposed silvicultural method.

关键词： Aggregated retention Dispersed retention Microenvironments environmental variables Biometric values Biomass allocation eco-physiology

Visual grading criteria for Japanese larch ( larix kaempferi ) structural timber from Spain

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Journal of Forestry Research 2020年第6期31卷 2605-2614页

作者： Mari-Jose Barriola José-Ramón Aira edgar lafuente Tknika LHri Aplikatutako Ikerketa eta Berrikuntzako EAEko zentroaZamalbide Auzoa z/g20100 ErrenteriaGipuzkoaSpain escuela de Ingeniería de la industria Forestal Agronómica y de la BioenergíaUniversidad de ValladolidUVa-Campus Duques de Sorias/n42005 SoriaSpain Cesefor Centro de Servicios y Promoción Forestal y de su Industria de Castilla y LeónCalle C42005 SoriaSpain

larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:laricio pine(Pinus nigra Arn.var.Salzmannii),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata D.Don),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(larix kaempferi(lamb.)Carr.)which diff erentiates between 2 visual classes,MeG-1 and MeG-2.Characteristic strength values were calculated for each class(fk,MeG-1=31.80 MPa,f k,MeG-2=24.55 MPa),mean module of elasticity(e 0,mean,MeG-1=13,082 MPA,e 0,mean,MeG-2=12,320 MPA)and density(ρk,MeG-1=456.6 kg m−3,ρk,MeG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MeG-1,and a strength class of C24 to visual class MeG-2.

关键词： Japanese larch wood Visual grading Strength class Mechanical properties density