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Deforestation and fragmentation trends of seasonal dry tropical forest in Ecuador: impact on conservation

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Forest Ecosystems 2021年第3期8卷 615-627页

作者： Carlos A.Rivas JoséGuerrero-Casado rafael m.navarro-Cerillo Instituto de Ciencias Básicas Universidad Técnica de ManabíPortoviejoManabíEcuador Department of Forest Engineering Laboratory of DendrochronologySilviculture and Global Change–DendrodatLab–ERSAFUniversity of CordobaCampus de RabanalesCrta.IVkm.396E-14071 CordobaSpain Departamento de medicina Veterinaria Facultad de Ciencias VeterinariasUniversidad Técnica de ManabíPortoviejoManabíEcuador Department of Zoology University of CordobaCampus de Rabanales14071 CordobaSpain

Background:Fragmentation and deforestation are one of the greatest threats to forests,and these processes are of even more concern in the tropics,where the seasonal dry forest is possibly one of the most threatened ecosystems with the least remaining surface area.methods:The deforestation and fragmentation patterns that had occurred in Ecuadorian seasonal dry forests between 1990 and 2018 were verified,while geographic information systems and land cover shapes provided by the Ecuadorian ministry of the Environment were employed to classify and evaluate three types of seasonal dry forests:deciduous,semi-deciduous,and transition.The study area was tessellated into 10 km2 hexagons,in which six fragmentation parameters were measured:number of patches,mean patch size,median patch size,total edge,edge density and reticular fragmentation index(RFI).The RFI was also measured both outside and inside protected natural areas(unprotected,national protected areas and protected forest).moreover,the areas with the best and worst conservation status,connectivity and risk of disappearance values were identified by means of a Getis-Ord Gi*statistical analysis.Results:The deforestation of seasonal dry forests affected 27.04%of the original surface area still remaining in 1990,with an annual deforestation rate of−1.12%between 1990 and 2018.The RFI has increased by 11.61%as a result of the fact that small fragments of forest have tended to disappear,while the large fragments have been fragmented into smaller ones.The semi-deciduous forest had the highest levels of fragmentation in 2018.The three categories of protection had significantly different levels of fragmentation,with lower RFI values in national protected areas and greater values in protected forests.Conclusions:The seasonal dry forest is fragmenting,deforesting and disappearing in some areas.An increased protection and conservation of the Ecuadorian seasonal dry forest is,therefore,necessary owing to the fact that not all protection measures have been effective.

关键词： Deciduous forest Semi-deciduous forest Remnant forest Patch isolation Habitat loss Protected areas

Distribution of malpighia mexicana in mexico and its implications for Barranca del Río Santiago

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Journal of Forestry Research 2021年第3期32卷 1095-1103页

作者： martín Tena meza Rafael M.navarro-Cerrillo Diego Brizuela Torres Instituto de Botánica Centro Universitario de Ciencias Biológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100.Nextipac45200 ZapopanJaliscoMexico Depto.Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio ClimáticoDendrodatLab-ERSAFUniversidad de CórdobaCampus de RabanalesCtra.N-IVkm.39614071 CórdobaSpain Departamento de Producción Forestal Centro Universitario de CienciasBiológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100 Nextipac45200 ZapopanJaliscoMexico

Wild plants represent relatively unexplored resource of high economic potential,especially as an alternative to developing new crops and,even more relevant,for improving existing crops and contributing to nutrition and health.The wild species m alpighia mexicana(manzanita)has a wide tradition of food,medicinal and ornamental use in mexico.It is part of the American-origin group of tropical shrubs that produce edible red fruits,such as A cerola,which is considered the most important natural source of vitamin C in the world.Given the role played by m.mexicana in mexico,and particularly in Barranca del Río Santiago(Santiago River Canyon),we modelled its potential distribution in both geographical areas.We used species'records from databases,local herbaria and records collected by the authors as well as climatic variables representing long term average,variability and extreme conditions of temperature and precipitation.To fit the models we used the modelling algorithm maxent and selected an adequate configuration by testing a range of model complexity settings.The results indicate a clear species preference for warm-dry tropical forest,most extensively in the Balsas river depression and the central valleys of Oaxaca.The probability of the species presence in the western region was also high,although the probability was also high for smaller surface areas,such as the region of Santiago river canyons,which are covered by warm-dry tropical forests.

关键词： malpighia mexicana maxent Warmdry tropical forest Río Santiago Genetic resources Ecological niche model manzanita

Clones identification of Sequoia sempervirens (D. Don) Endl. in Chile by using PCR-RAPDs technique

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第2期10卷 112-119页

作者： manuel TORALIBAEZ margarita CARU miguel A. HERRERA Luis GONZALEZ Luis m. mARTIN Jorge mIRANDA rafael m. navarro-cerrillo Department of Forest management Faculty of ForestryUniversity of Chile Santa Rosa 11315La PintanaSantiagoChile Department of Ecological Sciences Faculty of SciencesUniversity of ChileSanta Rosa 11315La PintanaSantiagoChile Department of Forestry School of Agriculture and Forestry University of Córdoba14080 CórdobaSpain Department of Genetic School of Agriculture and ForestryUniversity of Córdoba14080 CórdobaSpain Department of Forest management Faculty of ForestryUniversity of ChileSanta Rosa 11315La PintanaSantiagoChile

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D. Don) Endl. in Chile. Ten (out of 34) clones from introduction trial located in Voipir-Villarrica, Chile, were studied. The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction. The PCR tests were carried out employing 10-mer random primers. The amplification products were detected by electrophoresis in agarose gels. Forty nine polymorphic bands were obtained with the selected primers (BG04, BF07, BF12, BF13, and BF14) and were ordered according to their molecular size. The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was con- structed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGmA). Of the primers tested, 5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism. A total of 49 polymorphic RAPD bands were detected out of 252 bands. The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones, suggesting a geographic relationship. The results indicate that the RAPD markers permitted the identification of the assayed clones, although they are derived from the same geo- graphic origin.

关键词： RAPD标记技术 PCR检测基因型鉴定北美红杉无性系随机扩增多态性DNA 智利基因组DNA提取

Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, mexico under community forest management

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Journal of Forestry Research 2019年第1期30卷 143-155页

作者： rafael m~a navarro cerrillo Dennis J.Esteves Vieira Susana Ochoa-Gaona Bernardus H.J.de Jong m~a del mar Delgado Serrano Depto. Ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio Climático.Dendrodat Lab-ERSAF Universidad de Córdoba Depto. de Engenharia Florestal Faculdade de Engenharia Florestal Laboratório de Sensoriamento Remoto e Geotecnologia Universidade Federal de Mato Grosso Departamento de Ciencias de la Sustentabilidad El Colegio de la Frontera Sur-Unidad Campeche Depto. Economía Sociología y Política Agrarias Grupo de Evaluación y Restauración de Sistemas Agrícolas y Forestales-ERSAF Universidad de Córdoba

Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control.

关键词： Tropical and temperate forests Social forestry Land uses segmentation OBIA FRAGSTAT

Spatial pattern of landscape changes and consequence changes in species diversity between 1956-1999 of Pinus halepensis miller plantations in montes de malaga State Park (Andalusia, Spain)

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Open Journal of Ecology 2012年第3期2卷 154-165页

作者： rafael maria navarro-cerrillo José Ramón Guzmán-álvarez Inmaculada Clavero-Rumbao Carlos Ceaceros Department of Forestry Engineering University of Cordoba Cordoba Spain

Changes in forest diversity and the transforma- tion of coniferous plantations into more natural woodlands are of special interest in the medi- terranean. The aim of this study was to investi- gate changes in land use patterns and vegeta- tion cover from 1956 to 1999 in Pinus halepensis miller plantations in montes de málaga State Park in southern Spain. At the landscape level, a FRAGSTAT analysis was performed using aerial photographs. At the community level, a total of 47 sample plots were analyzed. Field measure- ments indicated the presence of a total of 70 species in the different vegetation types sam- pled. Shannon-Wiener (H), and Simpson’s (D) diversity indices showed the greatest species richness in Aleppo pine plantations (H = 1.54 ± 0.2;D = 3.88 ± 0.6), while Holm oak stands in the forested areas (H = 1.37 ± 0.1;D = 3.35 ± 0.6) and agricultural land (H = 1.33 ± 0.01;D = 2.80 ± 0.03) had lower values. FRAGSTATS analyses at land- scape and community levels indicated increases in patch richness, patch number, and percent of landscape mainly for pine plantations, Holm oak forests and shrub habitats. Replacement of agri- culture by conifer plantations led to the homo- genization of landscape structure. This change has modified the landscape by facilitating the recovery of indigenous tree species including Holm oak, which will likely lead to the future establishment of native forests in this area. Our findings suggest that pine plantations could fa- vour woody species diversity by increasing abundance and species richness in contrast to the situation in non-forested agricultural land.

关键词： Diversity Fragmentation Landscape metrics Vegetation Cover mediterranean Ecosystem

基于“水外交”视角浅论我国与湄公河流域国家的盐差能开发与合作

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安全与环境工程 2018年第2期25卷 23-29页

作者：涂亦楠 rafael m.Plaza 中国地质大学(武汉)公共管理学院湖北武汉430074 中国地质大学(武汉)国土资源部法律评价重点实验室湖北武汉430074

湄公河流域的水电开发竞赛已经对流域生态、各国社会经济发展和区域稳定产生了负面影响。面对湄公河流域错综复杂的"水外交"形势,由我国主导并推动的湄公河流域盐差能开发与合作能缓解上下游国家间的水资源开发争议,能推动"一带一路"倡... 详细信息

湄公河流域的水电开发竞赛已经对流域生态、各国社会经济发展和区域稳定产生了负面影响。面对湄公河流域错综复杂的"水外交"形势,由我国主导并推动的湄公河流域盐差能开发与合作能缓解上下游国家间的水资源开发争议,能推动"一带一路"倡议找到战略支点从而顺利推进。应用国际法和国际政治的价值评判、实证分析和政策定向方法,分析了湄公河流域的盐差能开发与合作对区域脱贫致富、共同发展、实现绿色能源转型和应对气候变化的作用,评估了推动盐差能开发合作的国际机制平台、条约制度和国际及区域融资渠道,并认为在技术成熟的条件下,我国与湄公河流域国家的盐差能开发与合作具有重大价值,能够成为流域未来的合作重点。

关键词：澜沧江-湄公河流域水外交水资源开发合作机制盐差能

On the nonclassical dynamics of cavity-assisted four-channel nonlinear coupler

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Chinese Physics B 2018年第11期27卷 498-505页

作者： rafael Julius Abdel-Baset m A Ibrahim Pankaj Kumar Choudhury Hichem Eleuch Faculty of Applied Sciences Universiti Teknologi MARA (UiTM) Faculty of Applied Sciences Universiti Teknologi Mara (UiTM) Perak Tapah Campus Institute of microengineering and Nanoelectronics Universiti Kebangsaan Malaysia Department of Applied Sciences and mathematics College of Arts and Sciences Abu Dhabi University Institute for Quantum Science and Engineering Texas A&M University College Station

The non-classical properties of light propagating in four-channel Kerr waveguides, confined in an optical cavity, are studied. The solution to the Hamiltonian of field operators is obtained semi-analytically by using symmetrically ordered phase-space representation. Full quantum analysis of the input coherent fields displays a strong transition of photon property between the super-Poissonian and sub-Poissonian statistics. It is found that the cavity-assisted multichannel system exhibits enhanced squeezing both in single-and compound-mode. This multichannel system may be utilized as an efficient quantumlight generator.

关键词： squeezed states Kerr effects Langevin equation

multiple ecological strategies explain the distribution of exotic and native C_(4) grasses in heterogeneous early successional sites in Hawai’i

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Journal of Plant Ecology 2017年第3期10卷 426-439页

作者： rafael de Oliveira Xavier Carla m.D’Antonio Ecology and Conservation Lab Department of HydrobiologyFederal University of São CarlosWashington Luís Highwaykm 235São CarlosSão Paulo 13565-905Brazil Environmental Studies Program 4312-L Bren University of CaliforniaSanta BarbaraCA 93106USA

Aims Biotic homogenization results in novel communities contain-ing multiple exotic species.many attributes that contribute to the dominance of invaders and increase invasibility of communities have been identified,but rarely have factors governing the domi-nance of co-occurring invaders been considered.Here we assess the presence and performance of five exotic and one native C_(4) grass species across local(microsite)and more broad-scale variation in fire history,soil age,altitude and precipitation.We ask whether species show preferences for the same conditions,whether all are constrained by poor soil development,and how their performance changes when alone versus co-occurring.In addition to providing information useful to managers who want to control some of these species,such information can help to predict how distributions might change with climate change methods We measured percent cover and plant height of each grass species in 64 plots in each of 15 sites,located in young volcanic substrates across environmental gradients in Hawai’i Volcanoes National Park,Hawai’i,USA.Sites varied in fire history and soil age,across altitu-dinal and precipitation gradients.We estimated microsite heteroge-neity by measuring rock cover and soil depth,where each species was present and in plots as a whole.We analyzed effects of pos-sible controlling variables using chi-square tests and Generalized Additive mixed models.Important Findings Two species(Schizachyrium condensatum and Hyparrhenia rufa)were absent in shallow soil,restricted to more mesic sites and showed increasing performance with soil depth.By contrast,two other species(Andropogon virginicus and melinis repens)tended to occur in shal-low soil with high rock cover across a wide range of sites.One addi-tional species(melinis minutiflora)was weakly affected by soil depth and was the dominant at higher elevation(more mesic)and on burned sites,especially in old soil.This species was largely absent from lower elevation sites,where the more widespread and opportunistic

关键词： elevation gradient fire invasive species melinis minutiflora soil depth

Calibration methodology for microscopic traffic simulation models of land ports of entry along the US-mexico border

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International Journal of modeling, Simulation, and Scientific Computing 2020年第3期11卷 40-59页

作者： David Salgado Peter T.martin Abhisek mudgal rafael m.Aldrete Texas A&m Transportation Institute 4050 Rio Bravo Drive Suite 212El Paso 79912USA New mexico State University Engineering Complex II Rm.215Las Cruces 88003USA Indian Institute of Technology(BHU)Civil Engineering Department Varanasi 221011 Uttar PradeshIndia

Non-commercial Land Ports of Entry(LPOEs)are unique transportation facilities controlling the ingress and egress of passenger vehicles from mexico to the United States and vice versa.The calibration of microscopic traffic simulation models of non-commercial LPOEs requires a deep understanding of operational processes and driving behavior at these facilities.This paper provides a methodology to guide modelers in calibrating microscopic traffic simulation models of non-commercial LPOEs.The methodology establishes a common framework for modeling operational processes and traffic operations.moreover,the methodology includes the value of four state variables that characterizes operations of passenger vehicles at non-commercial LPOEs.These variables are speed,acceleration,deceleration,and headway.The authors evaluated this methodology using the Otay mesa non-commercial LPOE as a case study.Results showed that this methodology could be potentially used to model non-commercial LPOEs along the US-mexico border and other border regions worldwide.

关键词： Land port of entry microsimulation calibration traffic models car-following models state variables