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Mediterranean forests represent critical areas that are increasingly affected by the frequency of droughts and fires, anthropic activities and land use changes. Optical remote sensing data give access to several essential biodiversity variables, such as species traits (related to vegetation biophysical and biochemical composition), which can help to better understand the structure and functioning of these forests. However, their reliability highly depends on the scale of observation and the spectral configuration of the sensor. Thus, the objective of the SENTHYMED/MEDOAK experiment is to provide datasets from leaf to canopy scale in synchronization with remote sensing acquisitions obtained from multi-platform sensors having different spectral characteristics and spatial resolutions. Seven monthly data collections were performed between April and October 2021 (with a complementary one in June 2023) over two forests in the north of Montpellier, France, comprised of two oak endemic species with different phenological dynamics (evergreen: Quercus ilex and deciduous: Quercus pubescens) and a variability of canopy cover fractions (from dense to open canopy). These collections were coincident with satellite multispectral Sentinel-2 data and one with airborne hyperspectral AVIRIS-Next Generation data. In addition, satellite hyperspectral PRISMA and DESIS were also available for some dates. All these airborne and satellite data are provided from free online download websites. Eight datasets are presented in this paper from thirteen studied forest plots: (1) overstory and understory inventory, (2) 687 canopy plant area index from Li-COR plant canopy analyzers, (3) 1475 in situ spectral reflectances (oak canopy, trunk, grass, limestone, etc.) from ASD spectroradiometers, (4) 92 soil moistures and temperatures from IMKO and Campbell probes, (5) 747 leaf-clip optical data from SPAD and DUALEX sensors, (6) 2594 in-lab leaf directional-hemispherical reflectances and transmittances from ASD spectroradiometer coupled with an integrating sphere, (7) 747 in-lab measured leaf water and dry matter content, and additional leaf traits by inversion of the PROSPECT model and (8) UAV-borne LiDAR 3-D point clouds. These datasets can be useful for multi-scale and multi-temporal calibration/validation of high level satellite vegetation products such as species traits, for current and future imaging spectroscopic missions, and by fusing or comparing both multispectral and hyperspectral data. Other targeted applications can be forest 3-D modelling, biodiversity assessment, fire risk prevention and globally vegetation monitoring.

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Plants are vital to human health and well-being, as well as helping to protect the environment against the negative impacts of climate change. They are an essential part of the 'One Health' strategy that seeks to balance and optimize the health of people, animals and the environment. Crucially, plants are central to nature-based solutions to climate mitigation, not least because soil carbon storage is an attractive strategy for mitigating greenhouse gas emissions and the associated climate change. Agriculture depends on genetically pure, high-quality seeds that are free from pests and pathogens and contain a required degree of genetic purity. This themed collection addresses key questions in the field encompassing the biochemical mechanisms that underlie plant responses and adaptations to a changing climate. This collection encompasses an analysis of the biochemistry and molecular mechanisms underpinning crop and forest resilience, together with considerations of plant adaptations to climate change-associated stresses, including drought, floods and heatwaves, and the increased threats posed by pathogens and pests.

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In this article we focus on the issue of determining the presence and status of the priority habitat 91I0* Euro-Siberian steppic woods with Quercus spp. in the South Slovak basin. As part of the issue, we try to verify the correctness of the procedure of the State Nature Conservancy of the Slovak Republic in the search for potential habitats and areas of European importance by converting the typological map to a map of habitats. Habitat 91I0* occurs in Slovakia in the form of three subtypes, namely Thermophilous and supra-Mediterranean oak woods (Carpineto-Quercetum and Betuleto-Quercetum), Acidophilous oak forests (Quercetum), while the last-named subtype is divided into two subunits: Medio-European acidophilous oak forests-part A and Pannonic hairy greenweed sessile oak woods-part B. Due to the current unsatisfactory state of the mentioned habitats, the requirement of the State Nature Conservancy of the Slovak Republic is to find and add new areas with the occurrence of habitat 91I0* in the south of Central Slovakia. During the mapping in the Lucenecká and Rimavská basins, greater emphasis was placed on the occurrence of the subtype Thermophilic Pontic-Pannonian oak forests on loess and sand, but its presence has not been confirmed. Subsequently, we focused on the search and identification of habitats in the model area, which is the area of European importance SKUEV0957 Uderinky. The result is a map of habitats in this area, which we then compare with a typological map, which determines the reliability of the converter used by the State Nature Conservancy of the Slovak Republic.

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Air pollution around refineries and factories is one of the major environmental challenges affecting forest ecosystems' health. Although there have been many studies on Iran's forest ecosystems, the physiological and morphological responses of Brant's oak (Quercus brantii Lindl.) leaves to the pollution of the gas refineries in the semiarid forests have not received much attention. We sampled healthy and mature leaves from four oak stands in different seasons (spring, summer, and autumn of 2019) and at various distances from the gas refinery (1,000, 1,500, 2,000, 2,500, and 10,000 m). The results showed that oak trees in different seasons and at different distances from the refinery had different physiological and morphological leaf trait responses to the pollution source. Oak trees with an air pollution tolerance index value of less than 11 were in a sensitive range to air pollution and can be used to biomonitor air pollution around the gas refinery in Zagros forests. Physiological traits in different seasons and at various distances in comparison with morphological traits (persistent reaction responses) were well distinguished from one another and were more affected by pollution. Oak trees in summer and autumn and at distances up to 2,500 m had rapid reaction responses, including oxidative stress indicators such as electrolyte leakage (EL), hydrogen peroxide, and different enzymatic and nonenzymatic antioxidants such as phenol, flavonoids, catalase, and proline. Because of their high sensitivity to atmospheric pollutant stresses, we recommend that these traits be used for rapid and low-cost environmental monitoring of pollution in different seasons and distances from pollution sources in semiarid ecosystems.

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Ant-like flies comprise nine Iberian endemic species of flightless Tachydromia. Severe knowledge gaps on distribution and ecological requirements hinder conservation assessments. Species distribution models were applied to unveil habitat suitability and to provide guidelines for future studies. An ensemble modeling approach combining ten different techniques was implemented with the biomod2 package. Occurrence data was partitioned into six sets, including two multi-species groups and four species. The most relevant drivers of habitat suitability are climate-related, followed by forest type and structure, according to well-defined biogeographic gradients. T. lusitanica and T. ebejeri are adapted to mild temperatures and high-humidity environments. Their distribution is connected to the Temperate-Eurosiberian life zone. T. semiaptera and T. iberica are adapted to progressively drier and hotter central and southern parts of the Iberian Peninsula, connected to transitional Temperate-submediterranean areas. Ant-like fly' ranges overlap with deciduous/marcescent oak species, acting as suitable indicators of their presence in Iberia. Southern marcescent forests emerge as "islands" with particular interest for future prospections. Ant-like flies are threatened by several factors such as climate change and habitat destruction, including urbanization and forest fires. This study provides vital tools to better assess the ant-like flies' conservation status and to manage their habitat.

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The oak lace bug (OLB), Corythucha arcuata (Hemiptera: Tingidae), was first identified as an invasive pest in Europe in northern Italy in 2000 and since then it has spread rapidly, attacking large forested areas in European countries. The OLB is a cell sap-sucking insect that is native to North America, with Quercus spp. as its main host. Its rapid expansion, successful establishment in invaded countries, and observations of more damage to hosts compared to native areas are most likely due to a lack of natural enemies, pathogens and competitors. In its native area, various natural enemies of OLBs have been identified; however, little is known about the occurrence and impact of OLB pathogens. None of the pathogenic fungi found on OLBs in natural conditions have been identified until now. In this study, we provide evidence of four entomopathogenic fungi that are naturally occurring on invasive OLBs found in infested pedunculate oak forests in eastern Croatia. On the basis of their morphology and multilocus molecular phylogeny, the fungi were identified as Beauveria pseudobassiana, Lecanicillium pissodis, Akanthomyces attenuatus and Samsoniella alboaurantium. The sequences generated for this study are available from GenBank under the accession numbers MT004817-MT004820, MT004833-MT004835, MT027501-MT27510, and MT001936-MT0011943. These pathogenic species could facilitate biological control strategies against OLBs.

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BACKGROUND: The Mexican hand tree or Canac (Chiranthodendron pentadactylon) is a temperate tree species of cloud and pine-oak forests of southern Mexico and Guatemala. Its characteristic hand-shaped flower is used in folk medicine and has constituted the iconic symbol of the Sociedad Botánica de México since 1940. Here, the evolutionary history of this species was estimated through phylogeographic analyses of nuclear DNA sequences obtained through restriction site associated DNA sequencing and ecological niche modeling. Total genomic DNA was extracted from leaf samples obtained from a representative number (5 to 10 per sampling site) of individuals distributed along the species geographic range. In Mexico, population is comprised by spatially isolated individuals which may follow the trends of cloud forest fragmentation. By contrast, in Guatemala Chiranthodendron may constitute a canopy dominant species near the Acatenango volcano. The distributional range of this species encompasses geographic provinces separated by the Isthmus of Tehuantepec. The objectives of the study were to: (i) estimate its genetic structure to define whether the observed range disjunction exerted by the Isthmus of Tehuantepec translates into separate populations, (ii) link population divergence timing and demographic trends to historical climate change, and (iii) test hypotheses related to Pleistocene refugia. RESULTS: Patterns of genetic diversity indicated high levels of genetic differentiation between populations separated by the Isthmus. The western and eastern population diverged approximately 0.873 Million years ago (Ma). Demographic analyses supported a simultaneous split from an ancestral population and rapid expansion from a small stock approximately 0.2 Ma corresponding to a glacial period. The populations have remained stable since the LIG (130 Kilo years ago (Ka)). Species distribution modelling (SDM) predicted a decrease in potential distribution in the Last Interglacial (LIG) and an increase during the Last Glacial Maximum (LGM) (22 Ka), Mid-Holocene (6 Ka) and present times. CONCLUSIONS: Divergence time estimations support the hypothesis that populations represent Quaternary relict elements of a species with broader and northernmost distribution. Pleistocene climatic shifts exerted major influence on the distribution of populations allowing dispersion during episodes of suitable climatic conditions and structuring during the first interglacial with a time period length of 100 Kilo years (Kyr) and the vicariant influence of the Isthmus. Limited demographic expansion and population connectivity during the LGM supports the moist forest hypothesis model.

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Two new species of Lactifluus subgenus Lactifluus were discovered during a three-year monitoring of the ectomycorrhizal fungi in a tropical oak forest from central Veracruz, Mexico. Systematic sampling of basidiomes allowed recording of the morphological variation of fruit-bodies in different growth stages along with their fructification season. Both new species were distinguished, based on macro- and micromorphological features and on molecular data. A phylogenetic analysis of a concatenated nuc rDNA ITS, D1 and D2 domains of nuc 28S rDNA (LSU) and the 6-7 region of the second largest subunit of the RNA polymerase II (rpb2) sequence dataset of species of Lactifluus is provided. In the phylogeny inferred, one of the new species is sister to L. dissitus Van de Putte, K. Das & Verbeken and the other belongs to the group of species of L. piperatus (L.) Kuntze, sister to an unidentified species from U.S.A. The studied taxa grow under Quercus oleoides in the study site. The species are presented and illustrated here.

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Resumen El conocimiento sobre la riqueza y la distribución de las plantas epifítas vasculares es aún incompleto en muchas áreas de México. Un ejemplo es la región terrestre prioritaria (RTP) Cerros Negro-Yucaño, que se ubica en el noroeste del estado de Oaxaca y pertenece a la región mixteca alta (Ñuu Savi Sukun, Ñuu vixi). Con base en la revisión de material de herbario en 12 colecciones institucionales mexicanas y en la recolección de especímenes en algunas localidades, principalmente cubiertas por bosque de encino, en 17 de los 18 municipios que incluye la RTP, se compilo un listado de las angiospermas epífitas. Se registró la presencia de 40 especies, distribuidas en 13 géneros y cinco familias; 28 taxa son endémicos de México y tres de ellos se conocen solamente de Oaxaca. Los géneros Tillandsia (18 spp.) y Peperomia (4) fueron los mejor representados en el área. El bosque de encino fue el tipo de vegetación en el cual se encontraron más epífitas (32 spp.) y también el intervalo altitudinal de 1 900 a 2 100 m (19 spp.). Plantas en floración de Artorima erubescens, Laelia albida, L. furfuracea y Prosthechea karwinskii, son utilizadas por pobladores de la región como ornamentales, durante las celebraciones religiosas de Día de Muertos y Semana Santa. Este impacto humano podría representar una amenaza para las poblaciones silvestres de estas especies en el futuro.(AU)

Abstract The knowledge on richness and distribution of epiphytic vascular plants is still incomplete in many areas of Mexico. An example is the terrestrial priority region (RTP) Cerros Negro-Yucaño, which is located in the Northwest portion of Oaxaca and belongs to the Mixteca Alta Region (Ñuu Savi Sukun, Ñuu Vixi). Based on herbarium material revision of 12 Mexican institutional collections and the collection of specimens in some localities, mainly covered by oak forest, in 17 of the 18 municipalities included in the RTP, we compiled a list of epiphytic angiosperms. The presence of 40 species, distributed in 13 genera and five families was recorded; 28 taxa are endemic to Mexico and three of them are only known from Oaxaca. The genera Tillandsia (18 spp.) and Peperomia (4) were the best represented genera in the area. Oak forest was the type of vegetation in which the most of the epiphytes were found (32 spp.), and also the altitudinal range between 1 900 and 2 100 m (19 spp.). Flowering plants of Artorima erubescens, Laelia albida, L. furfuracea, and Prosthechea karwinskii are used by the local people as ornamentals during the religious celebrations of Day of the Dead (Mexico) and Holly Week. This human impact might be a threat to the wild populations of these species in the future.(AU)

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In northern Japan, coastal oak forests consist of Quercus dentata (Qd) on the coastal side and Q. mongolica var. crispula (Qc) on the inland side. In the forests of northern Hokkaido, Qd is rare, and a coastal ecotype of Qc with some Qd-like traits grows on the coastal side. To reveal the genetic background of this ecotype, nuclear microsatellite genotypes in closely related oak taxa were obtained from the Eurasian continent, Sakhalin, and Hokkaido. The clustering of these genotypes suggests an admixture of Qd in the coastal ecotype of Qc. Next, we evaluated the effects of admixture and coastal stress on the leaf and shoot traits of Qc and Qd along coastal-inland gradients in northern Hokkaido. The admixture of Qd in Qc was quantified by the Qd ancestry proportions. Coastal stress causes bud mortality in the upper parts of shoots and was quantified by the survival patterns of buds in shoots. The genetic and environmental effects on the traits at Qd-abundant and Qd-rare sites were estimated using linear mixed models. The genetic effect was detected in all traits. Both genetic and environmental effects were detected in most traits. Some traits differed between Qd-abundant and Qd-rare sites in addition to these effects, indicating more Qd-like traits at Qd-rare sites. The findings suggest that an admixture of Qd characterizes the genetic background of the coastal ecotype of Qc and that not only the coastal stress but also the genetic background is responsible for the leaf and shoot traits of Qc and Qd in northern Hokkaido.

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Edge effects alter insect biodiversity in several ways. However, we still have a limited understanding on simultaneous responses of ecological populations and assemblages to ecotones, especially in human modified landscapes. We analyze edge effects on dung beetle populations and assemblages between livestock pastures and native temperate forests (Juniperus and pine-oak forests (POFs)) to describe how species abundances and assemblage parameters respond to edge effects through gradients in forest-pasture ecotones. In Juniperus forest 13 species avoided the ecotones: six species showed greater abundance in forest interior and seven in pasturelands, while the other two species had a neutral response to the edge. In a different way, in POF we found five species avoiding the edge (four with greater abundance in pastures and only one in forest), two species had a neutral response, and two showed a unimodal pattern of abundance near to the edge. At the assemblage level edge effects are masked, as species richness, diversity, functional richness, functional evenness, and compositional incidence dissimilarity did not vary along forest-pasture ecotones. However, total abundance and functional divergence showed higher values in pastures in one of the two sampling localities. Also, assemblage similarity based on species' abundance showed a peak near to the edge in POF. We propose that conservation efforts in human-managed landscapes should focus on mitigating current and delayed edge effects. Ecotone management will be crucial in livestock dominated landscapes to conserve regional biodiversity and the environmental services carried out by dung beetles.

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Vaejovis islaserranosp. n. is described from the Sierras Elenita and La Mariquita, Municipio de Cananea, Sonora, Mexico. This species belongs to the "vorhiesi" group of the genus Vaejovis and inhabits pine-oak forests in northern Mexico. This species is compared to its most similar species. This new species presents an interesting morphological difference from the rest of the species in the species-group: the absence of a subaculear tubercle or spine.

ResumenSe describe Vaejovis islaserranosp. n. de las Sierras Elenita y La Mariquita, en el Municipio de Cananea, Sonora, México. Esta especie pertenece al grupo "vorhiesi" dentro del género Vaejovis y que habita en los bosques de pino y encino del norte de México. Se le compara con las especies más similares morfológicamente. Esta nueva especie presenta una característica morfológica interesante para las especies del grupo: la ausencia de un tubérculo o espina subaculear.

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Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

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Increasing evidence indicates that there is ample diversity of plant virus species in wild ecosystems. The vast majority of this diversity, however, remains uncharacterized. Moreover, in these ecosystems the factors affecting plant virus infection risk and population genetic diversity, two traits intrinsically linked to virus emergence, are largely unknown. Along 3 years, we have analyzed the prevalence and diversity of plant virus species from the genus Potyvirus in evergreen oak forests of the Iberian Peninsula, the main wild ecosystem in this geographic region and in the entire Mediterranean basin. During this period, we have also measured plant species diversity, host density, plant biomass, temperature, relative humidity, and rainfall. Results indicated that potyviruses were always present in evergreen oak forests, with a novel virus species explaining the largest fraction of potyvirus-infected plants. We determined the genomic sequence of this novel virus and we explored its host range in natural and greenhouse conditions. Natural host range was limited to the perennial plant mountain rue (Ruta montana), commonly found in evergreen oak forests of the Iberian Peninsula. In this host, the virus was highly prevalent and was therefore provisionally named mediterranean ruda virus (MeRV). Focusing in this natural host-virus interaction, we analyzed the ecological factors affecting MeRV infection risk and population genetic diversity in its native wild ecosystem. The main predictor of virus infection risk was the host density. MeRV prevalence was the major factor determining genetic diversity and selection pressures in the virus populations. This observation supports theoretical predictions assigning these two traits a key role in parasite epidemiology and evolution. Thus, our analyses contribute both to characterize viral diversity and to understand the ecological determinants of virus population dynamics in wild ecosystems.

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Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the Americas. To examine diversification and biogeographic patterns in this group of snakes we assemble a multilocus data set consisting of over 6700bp encompassing three nuclear loci (NT-3, RAG-1, C-mos) and seven mitochondrial genes (12S, 16S, ATPase6, ATPase8, ND4, ND5, cytb). Fossil-calibrated phylogenetic and subsequent diversification rate analyses are implemented using maximum likelihood and Bayesian inference, to examine their evolutionary history and temporal dynamics of diversity. Based on ancestral area reconstructions we explore dispersal patterns throughout the New World. Cladogenesis occurred predominantly during the Miocene and Pliocene with only two divergences during the Pleistocene. Two different diversification rate models, advocating diversity-dependence, are strongly supported. These models indicate an early rapid radiation followed by a recent speciation rate decline. Biogeographic analyses suggest that the high elevation pine-oak forests of western Mexico served as a major speciation pump for the majority of lineages, with the desert biome of western North America colonized independently at least twice. All together, these results provide evidence for rapid diversification of rattlesnakes throughout the Mexican highlands during the Neogene, likely in response to continual orogenesis of Mexico's major mountain systems, followed by more recent dispersal into desert and tropical biomes.

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The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity.

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Structure and floristic composition of three oak forests in the northern region of the Central Cordillera in Colombia. Andean ecosystems harbor a high floristic diversity, which is being threatened by human disturbances such us deforestation and by the expansion of the agricultural frontier. One of these ecosystems are the Andean oak forests dominated by Quercus humboldtii, a threatened species in Colombia. We assessed the floristic composition and structure of three Andean oak forests located in three localities (San Andrés de Cuerquia, Belmira and Guarne) of Antioquia. The main goal was to determine whether these forests showed similarities in their structure and floristic composition. In each site, a permanent plot of 5000 m2 (0.5 ha) was established. All trees with D ≥ 10 cm were sampled and identified to species. The Importance Value Index (IVI) was calculated as the sum of relative density (DeR), dominance (DoR) and frequency (FR) of a species. Trees with 5 ≤ D < 10 cm and 2 ≤ D < 5 cm were registered in sub-plots of 0.05 and 0.0144 ha, respectively. Finally, we used Jaccard’s Index to quantify the floristic similarity among oak forest. When we considered all trees with D ≥ 10 cm in the three forests, the number of species ranged from 18 to 54, whilst the number of individuals ranged from 326 to 680. The Guarne oak forest showed the highest species richness. In all sites, Q. humboldtii (Fagaceae) was the most important species in relation to the IVI, while Clusia sp. (Clusiaceae) and Myrsine coriaceae (Myrsinaceae) were the most important species in San Andrés de Cuerquia, Clethra fagifolia (Clethraceae) was important only in Belmira and Myrcia popayanensis (Myrtaceae) was important in Guarne. The families with the highest number of species were Fabaceae, Melastomataceae and Rubiaceae. Floristic similarity among places was low. The size distribution of trees had an inverse J- shape curve for all sites with changes in the abundance for size class. The three oak forests differed in their structure and floristic composition probably because of different disturbance degrees. Rev. Biol. Trop. 57 (4): 1165-1182. Epub 2009 December 01.

La alta diversidad florística que albergan los ecosistemas andinos está siendo amenazada por fuertes presiones de origen antrópico. Uno de estos ecosistemas son los robledales, bosques dominados por la especie Quercus humboldtii, que se encuentra seriamente amenazada en Colombia porque su madera es valiosa comercial y dendroenergéticamente. En este estudio, se caracterizó la composición florística y la estructura de tres robledales de los Andes colombianos, con el fin de determinar su similaridad. En cada sitio, se estableció una parcela permanente (5 000 m²) donde se muestrearon todos los árboles con D ≥ 10 cm. En los tres sitios, la especie dominante fue Q. humboldtii, pero la similitud florística entre ellos no fue alta. La estructura por clases de tamaño para los tres sitios fue en forma de J invertida, aunque varió la abundancia de individuos por clase diamétrica. Los resultados indican que los robledales estudiados difieren en su composición florística y estructura a pesar de presentar características biofísicas similares. Las diferencias encontradas se deben posiblemente, a los diferentes factores que interactúan en cada sitio como la historia de uso, intensidad y duración de las perturbaciones antrópicas pasadas, topografía, fauna y clima local, que se ven reflejados en los parámetros estructurales de la vegetación.

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