Artículos de revistas: "Transect altitudinal"

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Bender, O. G. "Assessment of acclimation of Pinus sibirica mountain ecotypes ex situ on CO2 -gas exchange parameters". Проблемы ботаники южной сибири и монголии 20, n.º 1 (14 de septiembre de 2021): 66–69. http://dx.doi.org/10.14258/pbssm.2021014.

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Carbon dioxide gas exchange of vegetative scion Siberian stone pine ecotypes (Pinus sibirica Du Tour)from the West Sayan mountains altitudinal transect grown on the geographical grafting plantation in the south of theTomsk Region were studied. The altitudinal transect was represented by two ecotypes: low mountain zone and alpine zone.The age of the grafted trees was 20 years. It was shown that the photosynthesis intensity did not differ between ecotypessignificantly, and respiratory activity increased significantly along altitudinal transect and the differences were 40 %between ecotypes. The results of the experiment revealed that the respiration / photosynthesis ratio was 1.5 times higher inalpine ecotype than in low mountain ecotype, which indicates a lower plant productivity of the alpine ecotype. The resultsof measuring stomatal and mesophyll conductance showed that these values differ between ecotypes significantly. Alpineecotype was characterized with more high values of stomatal conductance, but low values of mesophyll conductancerelatively low-mountain ecotype. Alpine ecotype had more high values of CO2 in chloroplasts and electronic transportrates. The obtained data indicate the photosynthetic acclimation when ecotypes were moved to the warmer climate. Therespiratory activity are largely regulated by hereditary factors.

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Frahm, Jan-Peter y Ralf Ohlemüller. "Ecology of bryophytes along altitudinal and latitudinal gradients in New Zealand. Studies in austral temperate rain forest bryophytes 15." Bryophyte Diversity and Evolution 20, n.º 1 (31 de diciembre de 2001): 117–37. http://dx.doi.org/10.11646/bde.20.1.20.

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Six altitudinal transects through temperate rain forests were studied at different latitudes in the South and North Island of New Zealand with respect to species numbers of bryophytes, cover and phytomass of epiphytic bryophytes, composition of life forms and ratio liverworts : mosses. Phytodiversity of bryophytes is almost constant from the lowlands to the high montane belt but decreases in the subalpine belt. Similarly, phytomass and cover increase with elevation but decrease in the subalpine belt. The percentage of liverworts increases accordingly and can reach maxima of 80-90%. The most significant life forms are tails and wefts characteristic for hyperhygric conditions, pendents for cloud belts and cushions for subalpine belts. The altitudinal gradient is much stronger then the latitudinal gradient, that means the differences between the elevations within a transect are more important than the differences between the transects. They are attributed to the humidity. The temperate rain forests of New Zealand have similar bryological characteristics as the tropical rain forests in equatorial latitudes in 2000 – 3000 m altitude but differ in the drier subalpine belt and higher phytomass.

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Perales R., Hugo, S. B. Brush y C. O. Qualset. "Landraces of Maize in Central Mexico: An Altitudinal Transect". Economic Botany 57, n.º 1 (enero de 2003): 7–20. http://dx.doi.org/10.1663/0013-0001(2003)057[0007:lomicm]2.0.co;2.

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Choden, Kelzang, Jambay, Arjun Nepal, Choden y Bhagat Suberi. "Habitat Ecology of Epiphytic & Terrestrial Orchids in Langchenphu, Jomotsangkha Wildlife Sanctuary, Bhutan". Indonesian Journal of Social and Environmental Issues (IJSEI) 2, n.º 2 (22 de agosto de 2021): 143–54. http://dx.doi.org/10.47540/ijsei.v2i2.256.

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Orchids are the largest and diverse families of flowering plants. Orchids are found growing mostly in tropical climates affecting various communities socio-economically. Among many protected areas in Bhutan, Jomotshangkha Wildlife Sanctuary (JWS) is the least explored in terms of flora and fauna. The study was carried out to assess diversity, host tree preferences and to determine the growth zone of epiphytic orchids along the altitudinal gradient in Langchenphu gewog in JWS. Transect technique was used in which three trails transect were laid out with 10 sampling plots in each transect. Plots size of 20 m × 20 m along the altitudinal gradients were established maintaining an altitudinal interval of 100 meters between each sample plot. A total of 42 species of epiphytic orchids from 20 genera was recorded of23 host tree species under 15 families were recorded. A significant correlation between diversity of orchid and altitude was observed (r = .927, p < .05). Myrtaceae and Theaceae were the most preferred host tree families (14%) followed by Bignoniaceae (13%) and others respectively. The Study concludes that 57% of total species encountered prefers higher canopy & on a tree with rough bark, Pearson chi-square test (X2(1) = 4.7, p< .05) showed a significant difference between trunk, branches, and canopy. Many epiphytic orchids prefer dense canopy (n = 73, 47%) and living trees (99%). Future studies should be focused more on the flowering season for obtaining better information on orchid diversity in the study area.

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Drapikowska, Maria. "Variability of Anthoxanthum species in Poland in relation to geographical-historical and environmental conditions: morphological and anatomical variation". Biodiversity: Research and Conservation 30, n.º 1 (1 de junio de 2013): 3–61. http://dx.doi.org/10.2478/biorc-2013-0010.

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Abstract Three Anthoxanthum species are found in Poland: the native A. odoratum L. s. str. and A. alpinum Á. Löve & D. Löve, and the alien A. aristatum Boiss. Major problems within this genus concern: (1) population variation of the native A. odoratum, representing various phases of ecological expansion to anthropogenic habitats; (2) population variation of A. odoratum and A. alpinum along the altitudinal transect; and (3) variation between populations of A. aristatum colonizing new areas and habitats outside its natural range of distribution (chorological expansion). In this study, morphological and anatomical variation of the three Polish Anthoxanthum species was analysed in detail. The variation of A. odoratum and A. aristatum was analysed in respect of environmental differences: habitat types and soil parameters. In the Babia Góra massif, variability distribution along the altitudinal transect was analysed for two vicariants: A. odoratum and A. alpinum. A odoratum in this massif does not cross the upper forest limit (i.e. forest line), and lower montane populations are morphologically very similar to lowland populations. Morphological and anatomical differences were detected between populations of A. alpinum along the altitudinal transect in the Babia Góra massif, with distinct upper montane populations. Moreover, clear morphological differences were found between the two altitudinal vicariants. Lowland populations of A. odoratum are characterized by great morphological variation, only weakly correlated with the type of occupied habitat and the phase of ecological expansion. The detected morphological variation reflects only to a limited extent the environmental variation of occupied habitats, and is not significantly correlated with the phase of chorological expansion. Some soil parameters are significantly correlated with some morphological characters studied in all the Anthoxanthum species. The analysed anatomical features of stems and leaves show continuous variation in the three species.

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Zelazowski, Przemyslaw, Stefan Jozefowicz, Kenneth J. Feeley y Yadvinder Malhi. "Establishing the Position and Drivers of the Eastern Andean Treeline with Automated Transect Sampling". Remote Sensing 15, n.º 10 (22 de mayo de 2023): 2679. http://dx.doi.org/10.3390/rs15102679.

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The eastern Andean treeline (EATL) is the world’s longest altitudinal ecotone and plays an important role in biodiversity conservation in the context of land use/cover and climate change. The purpose of this study was to assess to what extent the position of the tropical EATL (9°N–18°S) is in near-equilibrium with the climate, which determines its potential to adapt to climate change. On a continental scale, we have used land cover maps (MODIS MCD12) and elevation data (SRTM) to make the first-order assessment of the EATL position and continuity. For the assessment on a local scale and to address the three-dimensional nature of environmental change in mountainous environments, a novel method of automated delineation and assessment of altitudinal transects was devised and applied to Landsat-based forest maps (GLAD) and fine-resolution climatology (CHELSA). The emergence of a consistent longitudinal gradient of the treeline elevation over half of the EATL extent, which increases towards the equator by ~30 m and ~60 m per geographic degree from the south and north, respectively, serves as a first-order validation of the approach, while the local transects reveal a more nuanced aspect-dependent pattern. We conclude that the applied dual-scale approach with automated mass transect sampling allows for an improved understanding of treeline dynamics.

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Tariq, Akash, Muhammad Adnan, Naser M. AbdElsalam, Hassan Fouad, Kamran Hussain, Riaz Ullah y Ahsan Ullah. "Richness and Cover of Nontimber Economic Plants along Altitude in Temperate Himalayan Forest-Use Types". Scientific World Journal 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/748490.

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Pakistani Himalaya stretches over a wide range of altitudinal gradients and supports high diversity of medicinal plants that are an important source for rural livelihood. Altitudinal effects on ground vegetation have already been indicated but ground vegetation is also under severe threat of grazing and over collection. The present study investigated the effect of altitude on medicinal plants abundance in both old-growth and derived woodland forests. Each of the five line transects was selected in old-growth and derived woodland forests. Each line transect consisted of four plots distributed at four altitudinal levels (2200, 2300, 2400, and 2500 m asl). Species richness under derived woodland had shown strong negative correlation (r=-0.95) with altitude while it was found to be nonsignificant under old-growth. Cover of most of the species such asVeronica laxa(r=-0.95,P≤0.05) had shown significant negative correlation with altitude under derived woodland. Cover abundance of some species likeValeriana jatamansiand Violacanescenshas also shown significant negative correlation under old-growth forest. Derived woodland can decrease the cover abundance of valuable medicinal plants towards extension at higher altitudes. Thus, protection of the derived woodland could serve as a tool for the improvement of rural livelihood and ecological restoration.

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Zhong, Mengying, Xinqing Shao, Ruixin Wu, Xiaoting Wei, Richard S. P. van Logtestijn y Johannes H. C. Cornelissen. "Contrasting altitudinal trends in leaf anatomy between three dominant species in an alpine meadow". Australian Journal of Botany 66, n.º 5 (2018): 448. http://dx.doi.org/10.1071/bt17247.

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Variation in leaf anatomical traits underpins the adaptations and phenotypic responses of plant species to their different natural environments. Temperature is a primary driver of plant trait variation along altitudinal gradients. However, other environmental drivers may also play important roles, and the interactions between drivers may have different effects on leaf anatomy for different species of the same larger clade. Such interactions might be especially important along shorter altitudinal (i.e. temperature) gradients. We predicted, therefore, that different monocot species could show idiosyncratic responses of leaf anatomical traits to a short altitudinal gradient. Moreover, for a species in which vegetative growth and reproduction are separated in time, its anatomical responses to altitude may differ and trade-offs between leaf and flowering stem anatomy may occur. To test these hypotheses, we examined leaf anatomy and δ13C signature (a possible indicator of anatomy-related water use efficiency or indicator of response to a decrease in CO2 concentration with altitude) of three dominant and widely distributed monocot species (Scirpus distigmaticus, Elymus nutans, Carex moorcroftii) from seven elevations in an alpine meadow on the Qinghai-Tibetan Plateau. In addition, we examined the flowering stem anatomy of S. distigmaticus, across a short altitudinal gradient (four elevations) in the same region. Leaf anatomical traits (e.g. epidermal cell area, epidermal cell thickness, cuticular layer thickness, xylem transect area, phloem transect area) varied with altitude, but the patterns varied substantially among species and among anatomical traits within species. Additionally, for S. distigmaticus, (allometric) coordination between leaves and flowering stems was apparent for xylem transect area and phloem transect area. Trade-offs between leaf and flowering stem traits were also found for epidermal cell area, epidermal cell thickness and mesophyll cell area. Leaves were more responsive to altitude in their anatomical traits than flowering stems in S. distigmaticus, perhaps reflecting their relatively short period of stem development during a climatically relatively favourable season compared with that for leaves, which already start growing earlier in the year. Further research is needed on the interactive effects of environmental variables, as well as vegetative versus reproductive phenology both across and within suites of species to better understand and upscale plant anatomical responses to climate warming in alpine environments.

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9

Kürschner, Harald. "Wissenschaftliche Ergebnisse der BRYOTROP-Expedition nach Zaire und Rwanda 5. Höhengliederung epiphytischer Moose im östlichen Kongobecken und den angrenzenden Gebirgsstöcken (Parc National de Kahuzi-Biega/Zaire, Forêt de Nyungwe/Rwanda)." Bryophyte Diversity and Evolution 11, n.º 1 (31 de diciembre de 1995): 77–85. http://dx.doi.org/10.11646/bde.11.1.5.

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By mean of a line-taxation (ordination), the floristic discontinuities of epiphytic bryophytes were shown within an altitudinal gradient from the eastern Congo basin to the mountains of the Riftvalley (Mt. Kahuzi) (BRYOTROP III-transect). By this ordination, the epiphytic vegetation can be grouped into four ecological groups, indicating the climatic factors. They show a strong correlation to the known altitudinal zonation, the different forest zones, and the plantsociological classification. These groups consist of taxa of different relationships which grow and evolve under similar environmental conditions.

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10

Osono, Takashi y Dai Hirose. "Altitudinal distribution of microfungi associated with Betula ermanii leaf litter on Mt. Rishiri, northern Japan". Canadian Journal of Microbiology 55, n.º 7 (julio de 2009): 783–89. http://dx.doi.org/10.1139/w09-030.

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The altitudinal distribution of microfungi associated with Betula ermanii Cham. leaf litter was investigated on Mt. Rishiri (1719 m), northern Japan. Fallen leaves were collected at five sites of different altitudes (appoximately 300, 600, 900, 1200, and 1500 m above sea level) along a transect on the northern slope of Mt. Rishiri. A total of 35 species were isolated from Betula leaf litter of which 12 occurred frequently and were regarded as dominant microfungi. Species richness, diversity, and equitability of microfungal assemblages were lower at Site 1500 than at the other sites. Similarities in species composition were relatively high among Sites 300, 600, and 900, but similarities between these sites and sites at the higher altitudes (i.e., Sites 1200 and 1500) were relatively low. Similarity of species composition was relatively low between Sites 1200 and 1500. Cluster analysis showed that the 12 major microfungal species were classified into four groups according to their pattern of altitudinal distribution that peaked at Sites 600, 900, 1200, and 1500, respectively. These results suggest that the diversity and species composition of Betula microfungi are sensitive to environmental changes along the altitudinal transect on Mt. Rishiri, and this is especially so at the altitudes higher than approximately 1200 m. This implies that future environmental changes will have impacts on mountainous ecosystems through the changes in diversity and functional aspects of microfungal assemblages.

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11

Brühl, Carsten A., Maryati Mohamed y K. Eduard Linsenmair. "Altitudinal distribution of leaf litter ants along a transect in primary forests on Mount Kinabalu, Sabah, Malaysia". Journal of Tropical Ecology 15, n.º 3 (mayo de 1999): 265–77. http://dx.doi.org/10.1017/s0266467499000802.

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The ant communities of the leaf litter were studied along an elevational gradient on Mount Kinabalu in primary rain forest systems ranging from dipterocarp hill forest to dwarf forest of the highest altitudes (560, 800, 1130, 1360, 1530, 1740, 1930, 2025, 2300, 2600 m a.s.l.). The litter ant fauna along the gradient included 283 species of 55 genera. The number of ant species in the leaf litter decreased exponentially without evidence of a peak in species richness at mid-elevations. This result is in contrast to many findings on altitudinal gradients in ants and other animal groups. Most ant species have a very limited altitudinal range leading to high turnover values when comparing communities of different altitudes. Of the ant species, 74% were even restricted to one site. As evident from this study, altitudinal ranges of species are very narrow. Elevational gradients are therefore extremely species-rich and might serve as a prime example of hot spots of biodiversity. This fact is of great concern when implementing conservation strategies.

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Albano, Paolo G., Pamela D'occhio, Grazia Strazzari, Fabio Succetti y Bruno Sabelli. "Land-mollusc forest communities along an altitudinal transect in northern Italy". Journal of Molluscan Studies 80, n.º 1 (febrero de 2014): 55–61. http://dx.doi.org/10.1093/mollus/eyt041.

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13

Hackenberger, Branimir K., Davorka Jarić y Stjepan Krčmar. "Distribution of Tabanids (Diptera: Tabanidae) Along a Two-Sided Altitudinal Transect". Environmental Entomology 38, n.º 6 (1 de diciembre de 2009): 1600–1607. http://dx.doi.org/10.1603/022.038.0611.

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14

El Sawaf, B. M., A. Shoukry, S. El Said, R. P. Lane, M. A. Kenawy, J. C. Beier y S. Abdel Sattar. "Sandfly species composition along an altitudinal transect in southern Sinai, Egypt". Annales de Parasitologie Humaine et Comparée 62, n.º 5 (1987): 467–73. http://dx.doi.org/10.1051/parasite/1987625467.

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15

Kitayama, K. "An altitudinal transect study of the vegetation on Mount Kinabalu, Borneo". Vegetatio 102, n.º 2 (octubre de 1992): 149–71. http://dx.doi.org/10.1007/bf00044731.

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KURT, Yusuf, Behiye B. BILGEN, Nuray KAYA y Kani ISIK. "Genetic Comparison of Pinus brutia Ten. Populations from Different Elevations by RAPD Markers". Notulae Botanicae Horti Agrobotanici Cluj-Napoca 39, n.º 2 (21 de noviembre de 2011): 299. http://dx.doi.org/10.15835/nbha3926276.

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Turkish Red Pine (Pinus brutia Ten.) is an important forest tree species in Turkey for various economic and ecological reasons. In this study, nine RAPD (Randomly Amplified Polymorphic DNA) primers were used to determine genetic variation within and among populations of P. brutia located at the Duzlercami common-garden test site. This site was established in 1979 and includes six natural populations of P. brutia from two altitudinal transects extending from the coast to higher elevations in the Antalya region of Turkey. A total of 32 polymorphic RAPD loci were found in the analyzed six populations. The mean proportion of polymorphic loci among population samples equals 100%, mean number of alleles for each locus = 2.0, effective allele number = 1.71, Shannon’s information index = 0.58, and mean Nei (1973)’s gene diversity value = 0.4. According to GST results, a high proportion of genetic diversity (95-99%) is found within populations. A relatively high genetic differentiation was found among altitudinal population pairs in both transect. Also, data on quantitative traits (total height and/or diameter) at different ages (13, 17, 30 years) were compared with molecular data. There are similarities between the results obtained from RAPD markers and those obtained from the quantitative traits. The differentiation in quantitative traits appears to be due to local adaptation of populations. Data suggest that priority should be given to the selection of material based on geographic origin along the altitudinal gradients of P. brutia populations to conserve the genetic resource of species.

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Halffter, Gonzalo, José R. Verdú, Juan Márquez y Claudia E. Moreno. "BIOGEOGRAPHICAL ANALYSIS OF SCARABAEINAE AND GEOTRUPINAE ALONG A TRANSECT IN CENTRAL MEXICO (COLEOPTERA, SCARABAEOIDEA)". Fragmenta Entomologica 40, n.º 2 (31 de octubre de 2008): 273. http://dx.doi.org/10.4081/fe.2008.99.

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Scarabaeinae and Geotrupinae (Coleoptera, Scarabaeoidea) species composition is analyzed along a 150 km long altitudinal transect that runs S-NE in the Mexican Transition zone. The transect is located in the state of Hidalgo in central-eastern Mexico. The spatial unit of analysis is the landscape. The transect crosses five different landscapes. As terms of reference for studying the geographic distribution of the species, the entomofauna distribution patterns for the Mexican Transition zone were used. The transect includes all the patterns established by Halffter for this zone. Only genera with northern origins were found in landscape of the Pachuca Sierra (mountain range). The two landscapes of the High Plateau (temperate and arid) have one genus with a northern origin (<em>Onthophagus</em>), along with species belonging to genera with Neotropical origins that evolved on the High Plateau. For the landscapes of the zacualtipán Sierra and the slope down to the Gulf–Las Huastecas region genera of Neotropical affinity dominate, and there are also some species with a tropical distribution and of northern-Old World origin. The relationship between the mountains and the phyletic lineages or genera of northern origin and of recent entry into the Mexican Transition zone is confirmed, as is that between the tropical lowlands and the Neotropical lines or genera, also recent arrivals. Taxa that arrived a long time ago, of either origin, do not exhibit this geographic-ecological dependence. The Hidalgo Transect is compared with two other, similar transects sampled in the Mexican Transition zone: the Cofre de Perote–Gulf Coast transect (Veracruz) and that of Manantlán (Jalisco). In the mountain landscapes, High Plateau and Tropical Lowlands, there were no important differences in the species composition of the groups studied. In contrast, in the Transition landscape (zacualtipán in the Hidalgo Transect) there were very notable differences. In the Cofre de Perote transect, an important functional group is missing from the treeless habitats: the roller Scarabaeinae. For the same landscape, in Manantlán, lineages with Neotropical affinities are represented by a single species which completely dominates the beetles of northern affinities. This contrasts markedly with the Hidalgo and Cofre de Perote transects where, in the Transition landscape, Neotropical taxa are well represented. It appears that, unlike the tropical lowlands where (geologically recent) penetration of Neotropical taxa is massive in all three transects, in the transition landscapes (originally covered by cloud forest) the penetration of Neotropical taxa is highly variable, and depends on the mountain range in which they are found. In the Conclusions section, we analyze how the beetle fauna with different distribution patterns have contributed to the composition of the fauna of the Hidalgo Transect and in general that of the Mexican Transition zone, resulting in a mixture (genera with northern-Old World affinity, and genera with Neotropical affinities) that give the Mexican Transition zone its unique character.

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18

Zhang, Man, Haktan Suren y Jason A. Holliday. "Phenotypic and Genomic Local Adaptation across Latitude and Altitude in Populus trichocarpa". Genome Biology and Evolution 11, n.º 8 (22 de julio de 2019): 2256–72. http://dx.doi.org/10.1093/gbe/evz151.

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Abstract Local adaptation to climate allows plants to cope with temporally and spatially heterogeneous environments, and parallel phenotypic clines provide a natural experiment to uncover the genomic architecture of adaptation. Though extensive effort has been made to investigate the genomic basis of local adaptation to climate across the latitudinal range of tree species, less is known for altitudinal clines. We used exome capture to genotype 451 Populus trichocarpa genotypes across altitudinal and latitudinal gradients spanning the natural species range, and phenotyped these trees for a variety of adaptive traits in two common gardens. We observed clinal variation in phenotypic traits across the two transects, which indicates climate-driven selection, and coupled gene-based genotype–phenotype and genotype–environment association scans to identify imprints of climatic adaptation on the genome. Although many of the phenotype- and climate-associated genes were unique to one transect, we found evidence of parallelism between latitude and altitude, as well as significant convergence when we compared our outlier genes with those putatively involved in climatic adaptation in two gymnosperm species. These results suggest that not only genomic constraint during adaptation to similar environmental gradients in poplar but also different environmental contexts, spatial scale, and perhaps redundant function among potentially adaptive genes and polymorphisms lead to divergent adaptive architectures.

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Olson, David M. "The distribution of leaf litter invertebrates along a Neotropical altitudinal gradient". Journal of Tropical Ecology 10, n.º 2 (mayo de 1994): 129–50. http://dx.doi.org/10.1017/s0266467400007793.

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ABSTRACTLeaf litter invertebrates were sampled at eight sites, approximately 250 m apart in elevation, along an altitudinal transect extending from primary lowland rainforest to cloud forest in western Panama. The study focused on several diverse and numerically important litter invertebrate taxa (e.g., ants, spiders, and beetles) that were effectively sampled using a combination of litter sifting and test tube pitfall traps. The mean altitudinal range of species was around 500 m (standard deviation 370 m) and approximately 50% of the species characteristic of a given elevation dropped out after a 500 m change in elevation in either direction. There was no evidence for distinct altitudinal zonation in leaf litter assemblages. Both species richness and number of individuals of most taxa showed a pronounced decline in the vicinity of the upward transition to cloud forests. The data also suggest a broad mid-elevation peak in sample species richness for the litter invertebrate fauna. The implications of the results for biodiversity conservation are discussed.

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POPESCU, Radu y Neculae ȘOFLETEA. "Spring and autumn phenology in sub-mesothermal beech stands from the southwestern extremity of the Carpathians". Notulae Botanicae Horti Agrobotanici Cluj-Napoca 48, n.º 2 (30 de junio de 2020): 1057–69. http://dx.doi.org/10.15835/nbha48211897.

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The research carried out was aimed to assessing the phenological behavior of beech (Fagus sylvatica L.) in the southwestern area of the Carpathians, in submesothermal forest sites, differentiated from the majority mesothermal ones of this species. The data obtained may be used for predicting the phenological changes of the species, especially in the Carpathian area, under the future influence of expected climate change. Assessments for spring and autumn phenology (buds burst -BB and foliation, flowering and leaves senescence) were carried out on a transect with a difference in altitude of 1000 meters, in phenological research areas located at 200 m, 700 m and 1200 m. At each altitude level, 100 trees of I and II Kraft classes were phenologically characterized: 50 trees on the south-facing slope (sunny exposure) and 50 on the north-facing slope (shade exposure).The phenological data were interpreted in relation to climate data recorded in each area by a HOBO U23 Pro v2 sensor. The site conditions of submesothermal climate in the low altitude area led to DOY (day of the year) values below 100. The phenological differentiation of populations is evident in relation with the altitude, while at the same altitudinal level the influence of the exposure was much lower. The gradiental values by altitude sectors highlighted the nonlinearity of the development of foliation phenophase, the value being lower in the first 500 m, where the beech is under the impact of the submesothermal climate. It has been proven both the dependence of the foliation onset depending on the cumulation of temperatures in relation to the DOY moment and also on the values recorded throughout the vegetative rest. The altitudinal gradiental values resulting for flowering in the first and second altitudinal half of transect also differentiate the stands, but are lower than that resulting for BB. The leaves senescence has a delay of 1.8 up to 2.4 days per 100 meters altitude, and the length of the vegetation season is reduced more sharply in the upper half of the analyzed altitudinal transect. The sub-mesothermal climate could be involved in condensation of spring phenophases in the stands of the lower half of the researched area. Our data may be used for predicting the phenological changes, especially in the Carpathian area, under the expected climate change.

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Loewen, Mark, Frank Wania, Feiyue Wang y Gregg Tomy. "Altitudinal Transect of Atmospheric and Aqueous Fluorinated Organic Compounds in Western Canada". Environmental Science & Technology 42, n.º 7 (abril de 2008): 2374–79. http://dx.doi.org/10.1021/es702276c.

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Riebe, Clifford S., James W. Kirchner y Robert C. Finkel. "Sharp decrease in long-term chemical weathering rates along an altitudinal transect". Earth and Planetary Science Letters 218, n.º 3-4 (febrero de 2004): 421–34. http://dx.doi.org/10.1016/s0012-821x(03)00673-3.

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23

Upadhyay, V. P. y J. S. Singh. "Decomposition of woody branch litter on an altitudinal transect in the Himalaya". Vegetatio 64, n.º 2-3 (enero de 1986): 49–53. http://dx.doi.org/10.1007/bf00044780.

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Shiryaev, Anton G., Ursula Peintner, Vladimir V. Elsakov, Svetlana Yu Sokovnina, Denis A. Kosolapov, Olga S. Shiryaeva, Nadezhda M. Devi y Andrei A. Grigoriev. "Relationship between Species Richness, Biomass and Structure of Vegetation and Mycobiota along an Altitudinal Transect in the Polar Urals". Journal of Fungi 6, n.º 4 (9 de diciembre de 2020): 353. http://dx.doi.org/10.3390/jof6040353.

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Aboveground species richness patterns of vascular plants, aphyllophoroid macrofungi, bryophytes and lichens were compared along an altitudinal gradient (80–310 m a.s.l.) on the Slantsevaya mountain at the eastern macroslope of the Polar Urals (Russia). Five altitudinal levels were included in the study: (1) Northern boreal forest with larch-spruce in the Sob’ river valley habitats; (2–3) two levels of closed, northern boreal, larch-dominated forests on the slopes; (4) crook-stemmed forest; (5) tundra habitats above the timberline. Vascular plant or bryophyte species richness was not affected by altitudinal levels, but lichen species richness significantly increased from the river valley to the tundra. For aphyllophoroid macrofungi, species richness was highest at intermediate and low altitudes, and poorest in the tundra. These results indicate a positive ecotone effect on aphyllophoroid fungal species richness. The species richness of aphyllophoroid fungi as a whole was neither correlated to mortmass stocks, nor to species richness of vascular plants, but individual ecological or morphological groups depended on these parameters. Poroid fungal species richness was positively correlated to tree age, wood biomass and crown density, and therefore peaked in the middle of the slope and at the foot of the mountain. In contrast, clavarioid fungal species richness was negatively related to woody bio- and mortmass, and therefore peaked in the tundra. This altitudinal level was characterized by high biomass proportions of lichens and mosses, and by high litter mortmass. The proportion of corticoid fungi increased with altitude, reaching its maximum at the timberline. Results from the different methods used in this work were concordant, and showed significant patterns. Tundra communities differ significantly from the forest communities, as is also confirmed by nonmetric multidimensional scaling (NMDS) analyses based on the spectrum of morphological and ecological groups of aphyllophoroid fungi.

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Kotas, Petr, Hana Šantrůčková, Josef Elster y Eva Kaštovská. "Soil microbial biomass, activity and community composition along altitudinal gradients in the High Arctic (Billefjorden, Svalbard)". Biogeosciences 15, n.º 6 (29 de marzo de 2018): 1879–94. http://dx.doi.org/10.5194/bg-15-1879-2018.

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Abstract. The unique and fragile High Arctic ecosystems are vulnerable to global climate warming. The elucidation of factors driving microbial distribution and activity in arctic soils is essential for a comprehensive understanding of ecosystem functioning and its response to environmental change. The goals of this study were to investigate microbial biomass and activity, microbial community structure (MCS), and their environmental controls in soils along three elevational transects in the coastal mountains of Billefjorden, central Svalbard. Soils from four different altitudes (25, 275, 525 and 765 m above sea level) were analyzed for a suite of characteristics including temperature regimes, organic matter content, base cation availability, moisture, pH, potential respiration, and microbial biomass and community structure using phospholipid fatty acids (PLFAs). We observed significant spatial heterogeneity of edaphic properties among transects, resulting in transect-specific effects of altitude on most soil parameters. We did not observe any clear elevation pattern in microbial biomass, and microbial activity revealed contrasting elevational patterns between transects. We found relatively large horizontal variability in MCS (i.e., between sites of corresponding elevation in different transects), mainly due to differences in the composition of bacterial PLFAs, but also a systematic altitudinal shift in MCS related to different habitat preferences of fungi and bacteria, which resulted in high fungi-to-bacteria ratios at the most elevated sites. The biological soil crusts on these most elevated, unvegetated sites can host microbial assemblages of a size and activity comparable to those of the arctic tundra ecosystem. The key environmental factors determining horizontal and vertical changes in soil microbial properties were soil pH, organic carbon content, soil moisture and Mg2+ availability.

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26

MORADI, HALIME y FARIDEH ATTAR. "Comparative study of floristic diversity along altitude in the northern slope of the central Alborz Mountains, Iran". Biodiversitas Journal of Biological Diversity 20, n.º 1 (4 de diciembre de 2018): 305–12. http://dx.doi.org/10.13057/biodiv/d200135.

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Moradi H, Attar F. 2019. Comparative study of floristic diversity along altitude in the northern slope of the central Alborz Mountains, Iran. Biodiversitas 20: 305-312. The Alborz is one of two main mountain chains in the north of Iran. The flora and vegetation of the sub-alpine and alpine zone of the central Alborz are less known comparing to the vegetation of lower altitudes with Hyrcanain forests. In this study, floristic composition and life-form spectra were investigated along an altitudinal transect ranging from 2000 m to the alpine and sub-nival peak of Mt. Rostam-Nisht at 4500 m. We compared the floristic diversity of the studied transect with the data obtained from an earlier studied transect in Kheyrud forest. A total of 299 taxa were found in the survey which showed high species diversity in the area. In addition, our results showed remarkable difference in life form categories between lower altitudes (Hyrcanian forests) and sub-alpine and alpine zones.

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27

Sáenz-Romero, C. y B. L. Tapia-Olivares. "Genetic Variation in Frost Damage and Seed Zone Delineation within an Altitudinal Transect of Pinus devoniana (P. michoacana) in Mexico". Silvae Genetica 57, n.º 1-6 (1 de diciembre de 2008): 165–70. http://dx.doi.org/10.1515/sg-2008-0025.

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AbstractWe explored the patterning of genetic variation among Pinus devoniana Lindl. (also known as P. michoacana Martínez) populations to develop guidelines for seed and seedling movements, intended for improving the matching between genotypes and environments regarding frost tolerance, in reforestation programs. Open-pollinated seed from 16 populations along an altitudinal transect (1600 to 2450 m) were collected near Morelia, State of Michoacán, México. A common-garden provenance test, established with 2.5-year-old seedlings, was assessed for frost resistance conducting a laboratory frost damage test (-9°C). Results indicate that there were significant differences among provenances (P = 0.0261) for frost damage. Variation among provenances was structured as an altitudinal cline, with populations from lower altitudes being the least tolerant to frost. Linear regression statistics suggest that for each increment of 100 m of provenance altitude, there will be a 5.2% decrease in frost damage. We suggest the use of two provisional altitudinal seed zones of 400 m breadth each (lower and upper limits for zone 1: 1600 m and 2000 m of altitude; for zone 2: 2000 and 2400 m, respectively), and for reforestation of a given site, the use of seedlings originated from seed of the same seed zone or within ±200 m of altitude from the elevation of the reforestation site.

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28

Gömöryová, Erika, Viliam Pichler, Ján Merganič, Peter Fleischer y Marián Homolák. "Changes of Soil Properties along the Altitudinal Gradients in Subarctic Mountain Landscapes of Putorana Plateau, Central Siberia". Land 11, n.º 1 (14 de enero de 2022): 128. http://dx.doi.org/10.3390/land11010128.

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Changes of soil properties along elevational gradients were studied in a less accessible and explored forest-tundra ecotone in the NW part of Central Siberia. Data on soil physical and chemical properties were collected along three horizontal transects at an elevation of 100–420 m a.s.l., at two localities differing in the slope angle. At each transect, five soil pits were excavated to a depth of 0.3–0.4 m. Soil samples were taken from the depths of 0–0.1 m, 0.1–0.2 m, and 0.2–0.3 m. The results showed a pronounced effect of slope angle on the pattern of soil properties along the elevational gradient. At the locality with a gentle slope, soils exhibited 2.5 times larger thickness of the surface organic layer (SOL), higher pH, and Na+ content, and lower C, N, Ald, and Fed concentration indicating slower pedogenic processes on this site. On the other hand, at the locality with a steeper slope, soil properties were better differentiated between transects situated along elevational gradient especially at the depths of 0.1–0.2 and 0.2–0.3 m. However, a clear positive or negative trend with the altitude was observed only for some soil characteristics, e.g., SOL, C, N, or Ald concentrations on the Lama location.

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Etges, William J. "Chromosomal Influences on Life-History Variation Along an Altitudinal Transect in Drosophila robusta". American Naturalist 133, n.º 1 (enero de 1989): 83–110. http://dx.doi.org/10.1086/284903.

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30

Herwitz, S. R. "Rainfall totals in relation to solute inputs along an exceptionally wet altitudinal transect". CATENA 14, n.º 1-3 (febrero de 1987): 25–30. http://dx.doi.org/10.1016/s0341-8162(87)80003-6.

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31

Brunello, Camilla Francesca, Christoff Andermann, Gerhard Helle, Francesco Comiti, Giustino Tonon, Achyut Tiwari y Niels Hovius. "Hydroclimatic seasonality recorded by tree ring δ18O signature across a Himalayan altitudinal transect". Earth and Planetary Science Letters 518 (julio de 2019): 148–59. http://dx.doi.org/10.1016/j.epsl.2019.04.030.

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32

Taylor, Peter John, Aubrey Munyai, Ian Gaigher y Rod Baxter. "Afromontane small mammals do not follow the hump-shaped rule: altitudinal variation in the Soutpansberg Mountains, South Africa". Journal of Tropical Ecology 31, n.º 1 (8 de diciembre de 2014): 37–48. http://dx.doi.org/10.1017/s0266467414000613.

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Abstract:Altitudinal transects of biodiversity are important to understanding macro-ecological patterns. Hump-shaped altitudinal profiles in species richness are a common pattern in terrestrial small-mammal communities studied previously mostly in New World mountain ranges. Based on capture–mark–recapture live-trapping conducted over four seasons (four nights per session) along an altitudinal transect from 1000 to 1747 m asl on the southern slopes of the Soutpansberg Mountains of northern South Africa, we recorded 12 species of small mammal, including nine rodents, two shrews and one elephant shrew (sengi). Three species of rodent and the sengi dominated the communities whilst six species were recorded with three or fewer captures. Although we found no effect of season, we found a significant linear increase in terrestrial small-mammal richness (but not Simpson's diversity, D) with altitude in the Soutpansberg Mountains located just north of the Tropic of Capricorn in South Africa. This trend could best be explained by an increase in the proportion of rocky cover and a change in vegetation from savanna to grassland. Peak densities of three common rodent species and one common insectivore varied from 10 ha−1 (Elephantulus myurus) to 54 ha−1 (Micaelamys namaquensis) and density showed no significant variation with season. However, density either declined (Aethomys ineptus) or increased (Rhabdomys dilectus and Elephantulus myurus) significantly with altitude; this variation was best explained by the proportion of rocky cover. Seasonal variation had a significant effect on body mass of two rodent species. A review of small-mammal studies from major mountain ranges in Africa and Madagascar found that the hump-shaped pattern is not common. Declines in richness with increasing altitude as well as cases of no significant altitudinal change were the most common patterns noted. Tropical African mountains (including the Soutpansberg with 27 species) have far higher small-mammal diversity than temperate African mountains.

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Hoffmann, Matthias H., Mikhail Yu Telyatnikov y Nikolai Ermakov. "Phytogeographical analysis of plant communities along an altitudinal transect through the Kuraiskaya basin (Altai, Russia)". Phytocoenologia 31, n.º 3 (24 de septiembre de 2001): 401–26. http://dx.doi.org/10.1127/phyto/31/2001/401.

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34

Gallardo-Salazar, José Luis, Roberto A. Lindig-Cisneros, Leonel Lopez-Toledo, Angel R. Endara-Agramont, Arnulfo Blanco-García y Cuauhtémoc Sáenz-Romero. "Analysis of the Vigor of Pinus hartwegii Lindl. along an Altitudinal Gradient Using UAV Multispectral Images: Evidence of Forest Decline Possibly Associated with Climatic Change". Forests 14, n.º 6 (6 de junio de 2023): 1176. http://dx.doi.org/10.3390/f14061176.

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Future climate forecasts predict major changes that will have negative impacts on the distribution, abundance, and dynamics of forest ecosystems. In Mexico, there is evidence of symptoms of massive forest decline; however, there is no consensus in terms of attributing these symptoms to climate change. This study aimed to provide evidence of forest decline possibly associated with climatic change in the highland pine (Pinus hartwegii Lindl.) populations of the Nevado de Toluca Flora and Fauna Protection Area. Using unmanned aerial vehicles (UAV) equipped with multispectral sensors, the study applied digital photogrammetry techniques, automated tree crown detection algorithms, and calculation of the normalized difference vegetation index (NDVI) and leaf chlorophyll index (LCI) to assess forest health across an altitudinal transect (from 3300 m to the timberline at 4040 m elevation). Climate analysis was conducted with TerraClimate data using mean annual temperature (MAT), April temperature, and Palmer Drought Severity Index (PDSI) from the studied altitudinal transect and its xeric limit. We found that lower altitude populations had significantly higher stress levels, indicating forest decline phenomena, while intermediate altitude populations showed greater vigor of the detected trees. Statistically significant differences in the NDVI and LCI values along the altitudinal gradient provided evidence of forest decline in terms of forest vigor and productivity, with the greatest disturbance found at the lower altitude of the examined forest species. The analysis of the climatic data revealed an increase in April temperature +1.4 °C of the xeric limit of the transect (low altitude) when comparing the reference period, 1961–1990 (mean: 12.17 °C), with the decade prior to our study (2011–2020; mean: 13.57 °C). This would be equivalent to an upward shift in elevation of 280 m of the xeric limit. In addition, the PDSI analysis revealed that droughts are becoming increasingly intense at a rate of 0.06 PDSI units per decade, with greater intensity in the last five years. These findings highlight the negative impacts of climate change on forest ecosystems and the urgent need for alternative forest management and conservation practices to increase resilience and adaptation in the temperate forests of Mexico. This study sets a precedent for further research to improve our understanding of the impacts of climate change on forest ecosystems and the development of sustainable management practices.

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Kopij, G. "Avian Diversity Along An Altitudinal Gradient In Highveld/Drakensberg Grasslands". Vestnik Zoologii 49, n.º 4 (1 de agosto de 2015): 351–60. http://dx.doi.org/10.1515/vzoo-2015-0038.

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Abstract Temperature and rainfall related to altitudinal gradients influence ecological and evolutionary responses of organisms to physical factors. In this study, the line transect method was used during the years 1996–2001 to compare resident (potentially breeding) bird communities in three altitudinal divisions in Highveld/Drakensberg grasslands in Lesotho: lowlands (< 1700 m a. s. l.), foothills (1700–2200 m a. s. l.) and highlands (> 2200 m a. s. l.). In total, 105 resident species were recorded. The total number of species recorded in lowlands was higher than that in highlands and foothills, but this difference was not statistically significant. The highland and foothill did not differ in numbers of species. A group of five species dominated at all three sites, and the proportion of dominant species in relation to the whole assemblage was very similar. The composition of the dominant group (species with more than 5 % of pairs) and the group of species most often encountered (in more than 80 % of transects) was, however, different. Only two species, Cape Canary Serinuscanicollis and Karoo Prinia Priniamaculosa were dominant in all three study areas, and just one species, the Cape Bunting Emberizacapensis, was dominant in two plots. Similarly, only two species, the Cape Turtle-Dove Streptopelia capicola and Cape Canary had a high frequency of occurrence in all three study areas, and two otherspecies, theKaroo Prinia and Cape Bunting — in two study areas. Simpson’s Diversity Index was strikingly the same (S = 0.96) for all three avian assemblages (lowland, foothill and highland) investigated. However, proportions of breeding pairs of some congeneric species were found to change with the altitude. The granivores were more common (44–45 %) in the foothills and highlands than in lowlands (36%), while insectivores were more common in the highlands (50 %) than in foothills and lowlands (36–37 %). In general, avifauna is relatively diverse and unique in the Highveld/Drakensberg grasslands. Results presented here provide data for further investigation of the effect of the supposed climate warming on the diversity and structure of avian communities.

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36

Frahm, Jan-Peter. "Ecology of bryophytes along altitudinal and latitudinal gradients in Chile". Bryophyte Diversity and Evolution 21, n.º 1 (24 de agosto de 2002): 67–79. http://dx.doi.org/10.11646/bde.21.1.12.

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The bryophyte vegetation in twenty-eight hectare plots in forests of S-Chile between 38° and 42°S and sea level and the forest line has been studied. Since bryophytes are fully dependend on atmospheric water and nutrient supply, they are good indicators of ecological conditions, especially for humidity. Therefore cover of epiphytic bryophytes, percentage of hepatics, composition of life forms and phytomass of epiphytic bryophytes were used as parameters. Cover and phytomass of epiphytic bryophytes as well as percentage of hepatics show moderate values in the lowlands, peak values in the montane belt (400-800m) and low values in the high montane to subalpine forests. This zonation corresponds with the composition of life forms and is attributed to a higher humidity in the montane belt. Life forms characteristic for the lowlands and submontane belts are pendants, those for the montane belt are wefts and tails, and those for the high montane and and subalpine belts are mats and cushions. The same zonation is found in New Zealand at comparable latitudes. The altitudinal differences are much stronger than the latitudinal ones. Compared with similar transect studies in New Zealand, there is a comparable zonation based on bryphytes. The percentage of hepatics as a good indicator of humidity, is – both in Chile and New Zealand - higher in the transects along the coast with higher precipitation, lower in transects in the inland with less precipitation, and increasing with altitude. Compared with tropical rain forests, the “mossiness” of temperate rain forests expressed by phytomass of epiphytic bryophytes per hectare, cover and percentage of hepatics is comparable to tropical rain forests above 2000 m, which is the corresponding elevation with regard to the mean annual precipitation. In Chile, however, there is a distinct decrease of “mossiness” in the high montane and subalpine forests, which is attributed to special climatological conditions, whereas bryophytes reach maximum cover and phytomass in the tropical high montane and subalpine forests. A comparison with montane forests in Europe in 48°N reveal, that phytomass and percentage of hepatics is distinctly less than in the true rain forests of the southern hemisphere.

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37

Geurts, Katrien, Maulid Mwatawala y Marc De Meyer. "Indigenous and Invasive Fruit Fly Diversity along an Altitudinal Transect in Eastern Central Tanzania". Journal of Insect Science 12, n.º 12 (enero de 2012): 1–18. http://dx.doi.org/10.1673/031.012.1201.

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38

Cañellas-Boltà, Núria, Valentí Rull, Josep Vigo y Arnau Mercadé. "Modern pollen—vegetation relationships along an altitudinal transect in the central Pyrenees (southwestern Europe)". Holocene 19, n.º 8 (18 de noviembre de 2009): 1185–200. http://dx.doi.org/10.1177/0959683609345082.

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39

Ernst, Nora, Francien Peterse, Sebastian F. M. Breitenbach, Hiambok J. Syiemlieh y Timothy I. Eglinton. "Biomarkers record environmental changes along an altitudinal transect in the wettest place on Earth". Organic Geochemistry 60 (julio de 2013): 93–99. http://dx.doi.org/10.1016/j.orggeochem.2013.05.004.

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40

Girardin, C. A. J., Y. Malhi, K. J. Feeley, J. M. Rapp, M. R. Silman, P. Meir, W. Huaraca Huasco et al. "Seasonality of above-ground net primary productivity along an Andean altitudinal transect in Peru". Journal of Tropical Ecology 30, n.º 6 (28 de agosto de 2014): 503–19. http://dx.doi.org/10.1017/s0266467414000443.

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Abstract:Solar irradiance and precipitation are the most likely drivers of the seasonal variation of net primary productivity (NPP) in tropical forests. Since their roles remain poorly understood, we use litter traps, dendrometer bands and census data collected from one hectare permanent plots to quantify the seasonality of above-ground NPP components and weather parameters in 13 sites distributed along a 2800-m altitudinal gradient ranging from lowland Amazonia to the high Andes. We combine canopy leaf area index and litterfall data to describe the seasonality of canopy production. We hypothesize that solar irradiance is the primary driver of canopy phenology in wetter sites, whereas precipitation drives phenology in drier systems. The seasonal rhythm of canopy NPP components is in synchrony with solar irradiance at all altitudes. Leaf litterfall peaks in the late dry season, both in lowland (averaging 0.54 ± 0.08 Mg C ha y−1, n = 5) and montane forests (averaging 0.29 ± 0.04 Mg C ha y−1, n = 8). Peaks in above-ground coarse woody NPP appears to be triggered by the onset of rainfall in seasonal lowland rain forests (averaging 0.26 ± 0.04 Mg C ha y−1, n = 5, in November), but not in montane cloud forests.

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41

Montoya, E., V. Rull y B. van Geel. "Non-pollen palynomorphs from surface sediments along an altitudinal transect of the Venezuelan Andes". Palaeogeography, Palaeoclimatology, Palaeoecology 297, n.º 1 (noviembre de 2010): 169–83. http://dx.doi.org/10.1016/j.palaeo.2010.07.026.

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42

Amundson, Ronald G., Oliver A. Chadwick, Janet M. Sowers y Harvey E. Doner. "Soil evolution along an altitudinal transect in the Eastern Mojave Desert of Nevada, U.S.A." Geoderma 43, n.º 4 (marzo de 1989): 349–71. http://dx.doi.org/10.1016/0016-7061(89)90063-3.

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Wilcke, Wolfgang, Yvonne Oelmann, Andrea Schmitt, Carlos Valarezo, Wolfgang Zech y Jürgen Homeier. "Soil properties and tree growth along an altitudinal transect in Ecuadorian tropical montane forest". Journal of Plant Nutrition and Soil Science 171, n.º 2 (abril de 2008): 220–30. http://dx.doi.org/10.1002/jpln.200625210.

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44

Zech, M., R. Zech, K. Rozanski, A. Hemp, G. Gleixner y W. Zech. "Revisiting Mt. Kilimanjaro: Do n-alkane biomarkers in soils reflect the δ<sup>2</sup>H isotopic composition of precipitation?" Biogeosciences Discussions 11, n.º 6 (3 de junio de 2014): 7823–52. http://dx.doi.org/10.5194/bgd-11-7823-2014.

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Abstract. During the last decade compound-specific deuterium (δ2H) analysis of plant leaf wax-derived n-alkanes has become a promising and popular tool in paleoclimate research. This is based on the widely accepted assumption that n-alkanes in soils and sediments generally reflect δ2H of precipitation (δ2Hprec). Recently, several authors suggested that δ2H of n-alkanes (δ2H,sub>n-alkanes) can also be used as proxy in paleoaltimetry studies. Here we present results from a δ2H transect study (~1500 to 4000 m a.s.l.) carried out on precipitation and soil samples taken from the humid southern slopes of Mt. Kilimanjaro. Contrary to earlier suggestions, a distinct altitude effect in δ2Hprec is present above ~2000 m a.s.l., i.e. δ2Hprec values become more negative with increasing altitude. The compound-specific δ2H values of nC27 and nC29 do not confirm this altitudinal trend, but rather become more positive both in the O-layers (organic layers) and the Ah-horizons (mineral topsoils). Although our δ2Hn-alkane results are in agreement with previously published results from the southern slopes of Mt. Kilimanjaro (Peterse et al., 2009, BG, 6, 2799–2807), a major re-interpretation is required given that the δ2Hn-alkane results do not reflect the δ2Hprec results. The theoretical framework for this re-interpretation is based on the evaporative isotopic enrichment of leaf water associated with transpiration process. Modelling results show that relative humidity, decreasing considerably along the southern slopes of Mt. Kilimanjaro (from 78% at ~ 2000 m a.s.l. to 51% at 4000 m a.s.l.), strongly controls δ2Hleaf water. The modelled δ2H leaf water enrichment along the altitudinal transect matches well the measured 2H leaf water enrichment as assessed by using the δ2Hprec and δ2Hn-alkane results and biosynthetic fractionation during n-alkane biosynthesis in leaves. Given that our results clearly demonstrate that n-alkanes in soils do not simply reflect δ2Hprec but rather δ2Hleaf water, we conclude that care has to be taken not to over-interpret δ2Hn-alkane records from soils and sediments when reconstructing δ2H of paleoprecipitation. Both in paleoaltimetry and in paleoclimate studies changes in relative humidity and consequently in δ2Hn-alkane values can completely mask altitudinally or climatically-controlled changes in δ2Hprec.

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45

Rajković, Draženko, Draško Grujić, Radosav Novčić y Radislav Mirić. "Population of Tengmalm’s Owl Aegolius Funereus in Kopaonik National Park (Central Serbia)". Acrocephalus 34, n.º 156-157 (1 de junio de 2013): 27–32. http://dx.doi.org/10.2478/acro-2013-0003.

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Abstract The altitudinal distribution, breeding density and population size of Tengmalm’s Owl Aegolius funereus was studied in Kopaonik National Park (central Serbia) during the 2011 and 2012 breeding seasons. The size of the study area was 24 km2. The survey method applied was a line transect in combination with stop points and playback of territorial male call. During the two-year research project, 37 territories were located. In Kopaonik National Park, Tengmalm’s Owl males inhabit Norway Spruce Picea abies, mixed Norway Spruce-Silver Fir Abies alba and Norway Spruce-European Beech Fagus sylvatica forests in the altitudinal belt stretching between 1,367 and 1,689 m a.s.l. The breeding density in the studied area was 8.3 territories/10 km2 in 2011 and 7.1 territories/10 km2 in 2012. Total population estimate of Tengmalm’s Owl in Kopaonik National Park is substantially higher than previously assumed, its 42-49 breeding territories making it currently the most important breeding site in Serbia.

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46

Gettinger, Donald y Scott L. Gardner. "Ectoparasitic mites of the genus Gigantolaelaps (Acari: Mesostigmata: Laelapidae) associated with small mammals of the genus Nephelomys (Rodentia: Sigmodontinae), including two new species from Peru". Acarologia 57, n.º 4 (4 de julio de 2017): 755–63. http://dx.doi.org/10.24349/acarologia/20174191.

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An extensive survey of small mammals and ectoparasites along an altitudinal transect in the Manu Biodiversity Reserve in Peru found the sigmodontine rodent genus Nephelomys infested by mites of the genus Gigantolaelaps Fonseca, 1939. Two distinct species co-occurred exclusively in the pelage of Nephelomys keaysi, G. inca Fonseca and G. minima n. sp. Nephelomys levipes, which replaces N. keaysi at higher elevations, was infested exclusively with a single new species, G. nebulosa n. sp. In this paper, we formally describe these new mite species, and provide more information on the morphology of G. inca.

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47

Cadavid, Juan, César Román Valencia y Andrés Gómez T. "Composition and structure of Anura (Amphibia) in an altitudinal transect from the Central Andes of Colombia". Revista del Museo Argentino de Ciencias Naturales 7 (2005): 103–18. http://dx.doi.org/10.22179/revmacn.7.329.

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Makunina, Natalya I. y Olga Yu Pisarenko. "Differentiation of forest vegetation across bioclimatic sector border (western part of the West Sayan Ridge)". Turczaninowia 24, n.º 4 (20 de diciembre de 2021): 84–98. http://dx.doi.org/10.14258/turczaninowia.24.4.8.

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A detailed description of the forests of the northern and southern macroslopes of western part of the West Sayan Ridge has been performed and differences in their forest vegetation have been analyzed. Along the West Sayan Ridge watershed, the important botanical and geographical boundary of the Altai-Sayan Mountains occurs. Its northern macroslope belongs to the humid bioclimatic sector; bioclimatic conditions throughout the southern macroslope vary in its different parts: the central and eastern parts are resided in the semihumid sector, while the western one is settled in the «rain shadow», where vegetation is similar to the semiarid sector one. The West Sayan background vegetation type is forest. The work is based on 120 complete geobotanical relevés made by the authors in 2019 using standard methods on test plots of 20 × 20 m. These plots had been uniformly distributed on a 300-kilometer transect crossing the northern and southern macroslopes of West Sayan’s western part. After all, 9 basic units of forest communities have been revealed, 6 of them are found to be altitudinal zone forests. These plant community positions in ecological-phytocenotic and floristic classification hierarchy have been ascertained. The altitudinal allocation and areas of altitudinal zone forests have been characterized and analyzed; the scheme of altitudinal zonation has been specified; the pictures in the text illustrate those results. In West Sayan’s western part, the northern and southern macroslopes are shown to have different altitudinal zone boundary marks and a different set of forest communities: six types of forests follow each other from north to south throughout 300 km. The significant hierarchical level of syntaxonomic differences of altitudinal zone forests on northern and southern macroslopes supports the presence of a bioclimatic barrier. In ecological-phytocenotic classification hierarchy these differences are reflected by the rank of classes of formations (deciduous, dark coniferous, and light coniferous forests substitute each other); in floristic classification hierarchy – the rank of classes (the forests of Brachypodio–Betuletea, Asaro–Abitetea, Vaccinio–Piceetea, and Rhytidio–Laricetea substitute each other from north to south).

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Loya-Rebollar, E., C. Sáenz-Romero, R. A. Lindig-Cisneros, P. Lobit, J. A. Villegas-Moreno y N. M. Sánchez-Vargas. "Clinal variation in Pinus hartwegii populations and its application for adaptation to climate change". Silvae Genetica 62, n.º 1-6 (1 de diciembre de 2013): 86–95. http://dx.doi.org/10.1515/sg-2013-0011.

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AbstractIn order to determine the genetic variation among populations of Pinus hartwegii along altitudinal gradients, and the possible adaptive decoupling due to climatic change, a common garden test was set up with 13 provenances collected along an altitudinal transect (3150 to 3750 masl; collection sites were every 50 m of altitudinal difference) from Pico de Tancítaro, Michoacán, west-central Mexico. The test evaluated trees aged 4.5 to 5.5 years, and contemporary and future (year 2030; six model-emission scenarios) climate variables were estimated. We found significant (P<0.005) differences among populations in total elongation, final seedling height, basal diameter, rate of elongation, dry weight of needles, branches and stem, total dry weight and first principal component. We found a significant association between population performance, expressed as first principal component values, and their climate, where the best climatic predictor was the frost free period (r2=0.90, P<0.0001). This result indicates that the patterning of genetic differentiation among populations is strongly associated with a climatic and altitudinal gradient. We propose a re-delineation of fixed climatic and altitudinal seed zoning for seed and seedling movement, based on intervals of 26 days of difference of frost free period: Zone 1, from 240 to 214 days of frost free period or 12 to 11°C or 3150 to 3350 masl; Zone 2, 214 to 188 days or 11 to 10°C or 3350 to 3550 masl; and Zone 3, 188 to 162 days or 10 to 9°C or 3550 a 3750 masl. Projecting at what altitude will occur the same frost free period values by year 2030, we suggested that populations should be shifted 400 m attitudinally upward, through a program of assisted migration, aiming to realign the populations to the climate for which they are adapted. Seedling deployment should use future (year 2030) fixed seed zones, with the same projected climatic interval values than contemporary climate, although at the following altitudinal limits: Zone 12030, from 3550 to 3750 masl; Zone 22030, 3750 to 3950 masl; and Zone 32030, 3950 to 4150 masl.

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Schneider, Julio V., Daniela Zipp, Juan Gaviria y Georg Zizka. "Successional and mature stands in an upper Andean rain forest transect of Venezuela: do leaf characteristics of woody species differ?" Journal of Tropical Ecology 19, n.º 3 (30 de abril de 2003): 251–59. http://dx.doi.org/10.1017/s0266467403003286.

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Changes in morphological and anatomical leaf characteristics of woody plant species along an altitudinal gradient as well as between a late-successional and mature upper montane rain forest were examined. For leaf size, the Raunkiaer-Webb classification system was applied. The mature-forest transect comprised eight plots of 0.1 ha between 2300 and 3300 m asl, the successional-forest transect, four plots between 2400 and 2750 m asl. The latter comprised structurally heterogeneous vegetation patches. For each plot the proportions of leaf size classes and of the different categories of leaf shape, margin, and apex were calculated. Leaf size and the proportion of drip-tips decreased with increasing elevation. Serrate leaf margins were more prominent at higher elevations. Stomatal density, leaf thickness and related anatomical characteristics did not show significant trends. Differences between the mature and successional forest plots were generally slight. The advanced age of the successional forest probably led to a convergent development of leaf characteristics.

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