Altitudinal Groups Research Articles

Effects of Environmental Factors on the Distribution and Diversity of Aquatic Oligochaetes

The aim of our study was to detect the actual distribution of oligochaete species and to identify their ecological differentiation with respect to environmental factors: altitude, temperature, oxygen concentration, conductivity, total organic carbon, and waterbody type. Although widespread, differentiation of oligochaete communities in four waterbody types and altitudinal groups can be observed through alpha and beta diversity. Their differences were analyzed using MANOVA, while the ecological preferences of species were presented with logistic Gaussian regression analyses. The highest number of the species of Oligochaeta was recorded in oligochaete communities in medium and large rivers. Total beta diversity decreased with the decreasing of waterbody size, the increasing of size of the substrate particles, river flow velocity, as well as altitude. Communities from small mountain rivers and streams and large and medium rivers with coarser substrate differed from other oligochaete communities. When coarser substrate was prevalent in smaller and medium rivers, a domination of a certain family was observed: Lumbriculidae (>800 m a.s.l.), Propappidae and Enchytraeidae (500–800 m), and Naididae (<500 m a.s.l.). Common species of Oligochaeta, with significantly overlapping ranges in running waters in Serbia, still show a clear grouping with respect to preference for certain types of waterbodies.

Past and present risk of spring frosts for fruit trees in the Czech Republic

Recent climate warming is reflected in the advanced onset of spring phenological phases of fruit trees and in so-called false springs. This then manifests as an increased risk of trees being damaged by late frosts in the sensitive growing stage. Based on the homogenised temperature series of 155 climatological stations divided into two altitudinal groups (below 300 m a.s.l. and 301–600 m a.s.l.), a climatological analysis of selected variables in relation to atmospheric circulation over the territory of the Czech Republic during the period 1961–2021 was performed. The number of frost days and the dates of their latest onset exhibited negative linear trends; however, only 16% and 20% were statistically significant. The onset of false spring (at least ten consecutive days with daily maximum ≥ 10 °C) was also characterised by decreasing trends, which significantly deepened after 1980. Spring frost days were particularly attributed to higher frequencies of anticyclonic circulation types such as the central anticyclone and circulation types with northeastern, eastern and southeastern airflow. False spring onset was particularly connected with the central anticyclone and circulation types with western and southwestern airflow. The increasing trends of frost risk days (days between the beginning of the false spring and the date of the latest frost with daily minimum < −1.5 °C) were statistically nonsignificant. Local series of fruit trees from southeastern Moravia proved to have significantly earlier onset of the first blossom and full blossoming phenophases. Although the damage by late frosts has been identified as an important factor contributing to low yields of fruit trees during the period 1996–2021 in the Czech Republic, other factors (e.g. other weather phenomena, diseases, pests, site, taking preventive measures against frost) must also be taken into account.

Distribution patterns of alpine flora for long-term monitoring of global change along a wide elevational gradient in the Western Himalayas

In the current context of climate change, the Western Himalayas are thought to be warming faster than the global average rate. Despite this rapid warming, our understanding of alpine vegetation composition and the underlying factors shaping its patterns in the Western Himalayan alpine highlands of Pakistan remains limited. Extensive field sampling was conducted at 24 sites ranging in altitude from 3300 m to 4200 m. The entire altitudinal range was divided into three belts i.e., low-altitude sites, medium-altitude sites, and high-altitude sites (HAS). Results revealed that alpine flora consisted of 251 species (belonging to 51 families. The findings revealed that 83 of the 251 species evaluated contributed significantly to the change in species composition between three altitudinal sites. The species that contributed the most to the variance in species composition between communities made up 75 % of the total, demonstrating that these species are important in structuring plant communities at different altitudes. Among the alpine flora, a significant (49 %) dominance was observed from nine families, comprising a total of 123 species. The largest family, Asteraceae, had the highest number of species, followed by Poaceae and Rosaceae. Hemicryptophytes emerged as the prevailing life form, while Microphylls were the dominant leaf type. Phytosociological Indices revealed that diversity levels decreased with increasing altitude, indicating a significant impact of altitude on plant diversity. Canonical correspondence analysis suggested that altitude, grazing, and soil erosion are important in explaining variance in plant distribution patterns in the alpine flora. Twelve indicator species were discovered in three different altitudinal groups. In the LAS, Bistorta affinis, Geranium himalayense, Poa nemoralis, and Sibbaldia cuneata, had a significant indicator value, whereas in the medium-altitude sites MAS Allium humile, Bistorta affinis, Juniperus communis, and Rhododendron campanulatum had significant p-values. In high altitude sites HAS, indicator plants were Bistorta affinis, Juniperus communis. Our results identified 51 vulnerable species with very low abundance values whereas 17 threatened species having extremely low (<0.1) abundance values are a vital conservation priority in the region. Results may be helpful to formulate immediate conservation management strategies to conserve the precious floristic wealth of the alpine Region.

Genomic analysis of Plasmodium falciparum isolates across different altitudinal zones along the slope of Mount Cameroon

BackgroundMalaria elimination is threatened by the emergence and rapid spread of drug resistance. Understanding the demographic history of Plasmodium falciparum and the genetic basis of adaptation to antimalarial treatment and host immunity is critical to elimination efforts. This study sought to characterize the diversity of P. falciparum isolates across different altitudes along the slope of Mount Cameroon.MethodologyUsing the Illumina next-generation sequencing platform P. falciparum isolates from low, intermediate and high altitudes along the slope of Mount Cameroon were studied to determine their genetic diversity, population structures, and signatures of selection in known drug resistance alleles.ResultsA total of 77,253 single-nucleotide polymorphisms were identified from 220 quality P. falciparum clinical isolates from high (24,214), intermediate (24,426), and low (28,613) altitude. About 49%, 48.2% and 30% of the parasite isolates from high, intermediate, and low altitudes, respectively had FWS values &amp;gt; 0.95 indicative of dominant mixed genotype infections and low population sub-structure with high potential for out-crossing. No significant difference was observed in within-host diversity while population structure analysis did not separate the isolates in the three major altitudinal groups by PCA, FST and admixtures, suggesting bidirectional gene flow among the populations. A total of 94 antigenic genes under balancing selection were detected in the area including vaccine candidate gene ama1, eba175, msp1, trap, dblmsp, and clag2. Moreover, 17 of these genes were identified to be under both recent positive directional and positive balancing selection including the prominent host immune target genes surfin 8.2, trap, and ama1. Recent directional selection analysis using integrated standardized haplotype score (iHS) did not detect any selection signatures in the Pfdhfr, Pfdhps, Pfmdr1, and PfK13 genes. Furthermore, no PfKelch13 validated mutation associated with artemisinin resistance was identified in this study and no structural divergence was noticed among the P. falciparum parasite populations across different altitudes around the Mount Cameroon region.DiscussionFindings revealed high genetic diversity and low population structure suggesting that malaria transmission remain high in the study area and parasite populations circulating around the slope of Mount Cameroon are homogenous.

Fish biodiversity and assemblages along the altitudinal gradients of tropical mountainous forest streams

Knowledge of the fundamental aspects of ecology such as the patterns of fish species distribution and biodiversity in the forest streams is the first and basic step to develop effective conservation strategies. Yet, studies on altitudinal changes of fish composition and assemblages in Bornean forest streams are scarce despite being one of the hotspots of biodiversity conservation. Hence, surveys on freshwater fish composition along the altitudinal gradients of the Baleh River Basin in Sarawak, Borneo were conducted from April 2014 to August 2015. The Baleh River Basin was divided into seven altitudinal groups with a total of 72 stations. Group elevation ranged from 53 to 269 m above sea level. The fish samples and environmental parameters were taken concurrently during samplings. A total of 3565 specimens belonging to six orders, 14 families, and 76 species were found in the present study. The most dominant family in the Baleh River Basin was Cyprinidae (74.4%), followed by Gastromyzontidae (16.2%) while the most dominant species was Tor tambra (12.9%), followed by Lobocheilos ovalis (12.3%). Fish abundance significantly higher at high altitude sites than those at low altitude sites except for Mengiong River which has the lowest fish abundance despite with high elevation. Species richness was found significantly lower in midstream segment. Noticeable altitudinal gradient of fish assemblages was observed along the Baleh River except a discontinuity at the midstream segment which is attributable to the poorer quality inflow from the Mengiong River coupled with the meandering feature of the segment. Fish abundance was significantly and positively correlated with elevation, water pH and conductivity while negatively correlated with turbidity. Anthropogenic activities in the Baleh River Basin had altered the environmental variables thus disrupted the altitudinal gradient of fish assemblages. This phenomenon is apparent when the Canonical Correspondence Analysis (CCA) revealed that the first axis (CCA1) explained 42.5% of the variation and has positive loading on dissolved oxygen (DO) and negative loading on water conductivity; whereas CCA2 explained 37.5% of the variation and positively loaded on elevation, water pH, and DO. The results demonstrated that Gastromyzon fasciatus preferred more oxygenated water than Protomyzon sp., G. sp 1, and G. punctulatus although they are all from Gastromyzontidae family that inhabiting high altitude sites. Barbonymus schwanenfeldii was also found most abundant with elevated dissolved oxygen value. On the other hand, Rasbora volzii and R. hosii inhabiting lower altitude sites with less oxygenated and more acidic water.

Observed changes in precipitation during recent warming: The Czech Republic, 1961–2019

AbstractThis paper presents a comprehensive spatiotemporal analysis of precipitation patterns over the territory of the Czech Republic for the 1961–2019 period. Monthly, seasonal and annual series of precipitation totals and numbers of precipitation days were calculated for four altitudinal groups and the entire Czech Republic, based upon the daily precipitation totals recorded by 531 rain‐gauge stations run by the Czech Hydrometeorological Institute. Analysis of series of monthly, seasonal and annual precipitation totals revealed relatively stable fluctuations, while linear trends remained largely insignificant. However, wavelet analysis indicated significant interannual variability on a timescale of 4–8‐years in seasonal and annual series. The minimum in annual variation tended to appear in February (also in January and, at higher altitudes in particular, in April) with the maximum favouring July (but also June and August). The relative proportions of annual totals taken up by winter precipitation increased with altitude, while the proportions for summer precipitation decreased with altitude. Linear trends in the numbers of precipitation days exhibited the most pronounced decreases from April to June, reflected in negative precipitation trends in April–June and positive in July–September. The results obtained are also presented in the broader (central) European context.

Newborn anthropometry, maternal capital, and altitude in the highland population from the province of Jujuy, Argentina.

To analyze variability in newborn (NB) anthropometry among Jujenean NBs as a function of geographic altitude (500 m to ≈4000 masl), maternal anthropometry and other maternal characteristics within the maternal capital framework. Data obtained from 41,371 mother/child pairs recorded in the Jujuy Perinatal Information System (SIP) between 2009 and 2014, including: NB and maternal weight, length/height and BMI; gestational age (corrected); maternal age, educational level, nutritional status, and marital status; birth interval; and planned pregnancy. Based on the declared place of residence, the prevalence of unsatisfied basic needs (% UBN) was determined and the data was split into two altitudinal groups: highlands (HL, >2500 masl) and lowlands (LL, <2500 masl). ANOVA, Chi-squared and Pearson tests were applied as needed. Statistical associations between the response variables-NB weight, length and BMI-and maternal and environmental variables were tested using a Generalized Additive Mixed Model (GAMM). All NB and maternal anthropometric variables were lower in HL compared to LL; they also presented negative correlations with altitude, except NB length. Apart from gestational age and birth interval, HL and LL presented statistically significant differences in all study variables. GAMM results showed that maternal anthropometry was the main influence on NB weight and length. Of all the maternal capital features examined, only maternal anthropometric variables were found to protect offspring against the negative impact of HL environments.

Spatial trends of Potamogetonaceae along an altitudinal gradient

Studying the effect of altitude on species distribution may help us to predict the response of species to future climate changes, which will likely cause upward migration of vegetation zones. In this study, we aimed to analyze distribution and abundance patterns of Potamogetonaceae along an altitudinal gradient and to determine the species characterizing a priori defined five altitudinal groups. We included 294 sampling for 19 species from 141 wetlands across Turkey with an elevation gradient of 2700 m. Analysis of similarities (ANOSIM) found significant differences in species assemblages only between some altitudinal groups. Seven species were found in either high or low altitudes. Stuckenia pectinata had the highest contribution to all groups except one in analysis of similarity percentages. Detrended correspondence analysis revealed a clear altitudinal gradient by placing species under six clusters. Even widespread species occurring in all altitudes showed a tendency of altitudinal preference. The results were inferred from our physicochemical measurements for the species and relevant literature. Exclusively highland species were found in waters with similar physical and chemical properties (i.e. low electrical conductivity, salinity, and ammonium concentrations). However, lowland species were sampled from very diverse aquatic habitats. Among the lowland species Potamogeton acutifolius was found under low values for the above-mentioned physicochemical water parameters but Althenia orientalis showed extremely high values, as well as Potamogeton coloratus and Potamogeton nodosus. Understanding elevational distribution of macrophytes is especially important due to difficulties in their upward migration and availability of suitable aquatic habitats.

Reflections of global warming in trends of temperature characteristics in the Czech Republic, 1961–2019

AbstractThis paper presents a comprehensive trend analysis of spatiotemporal temperature change patterns over the territory of what is now the Czech Republic (CR) during the 1961–2019 period. Employing daily mean temperatures (TAVG), maximum (TMAX) and minimum (TMIN) temperatures and diurnal temperature range (DTR), supplied by 133 stations of the Czech Hydrometeorological Institute, daily, monthly, seasonal and annual series were calculated for four altitudinal groups and the entire CR, for which linear trends were calculated and further analysed. For the purposes of relative trend comparison, the linear trends were also calculated from standardized series (mean 0, SD 1, in 1961–1990). All seasonal and annual TAVG, TMAX and TMIN series exhibit statistically significant increasing trends, with the exceptions of only a few cases for winter (DJF) and autumn (SON). DTR trends increase significantly in spring (MAM) and summer (JJA), but decrease in DJF and SON. The highest increases in trends occur in JJA and from stations at lower altitudes for groups I (up to 300 m asl) and II (301–600 m asl). Trends in JJA and SON TMIN are relatively higher than in TMAX, while the opposite holds true of DJF and MAM. Comparing the three decades after 1990 with the 1961–1990 normal, each decade was generally warmer than the previous period, with particularly enhanced warming in 2011–2019. This is also reflected in prominent increases in cumulative temperature sums throughout the year. The results obtained are discussed in the context of other European papers and with respect to explaining existing differences.

Ecological wood anatomy of Alnus nepalensis (Betulaceae) throughout Nepal

Abstract Variation in the wood structure of Alnus nepalensis D. Don (Betulaceae) in relation to tree size and habitat altitude was studied in four areas of Nepal: Tamur, Rolwaling, Budi Gandaki, and Bajhang-Khaptad. Alnus nepalensis is a pioneer tree distributed in the Himalayas from northern India to southwestern China and grows throughout Nepal in a wide altitudinal range from 200 m in the tropical zone to 3030 m at the upper limit of the temperate zone. Ecological trends in the wood structure of Alnus nepalensis varied between the studied areas, distinct in the Tamur area, but indistinct in other areas, and tended to be detected in areas with specimens from altitudinal ranges of 2000 m. When all the specimens were separated at 1800 m in elevation and analyzed as two altitudinal groups, features of vessel size and distribution and the ratio of solitary vessels had a significant correlation with tree height in both groups, and tall trees tended to have larger, more solitary vessels. Vessel element and fiber lengths did not have any significant trends in the lower group but had a negative correlation with altitude in the upper group along with the reduction of tree height. Thus, vessel size seems to facilitate the height growth of this pioneer tree, and shorter tracheary elements and more vessel multiples seem to be related to the adaptation of smaller trees at higher elevations.

Altitudinal variations in wing morphology of Aedes albopictus (Diptera, Culicidae) in Albania, the region where it was first recorded in Europe.

The rapid spread and settlement of Aedes albopictus mosquitoes across at least 28 countries in Europe, as well as several countries in Asia Minor, the Middle East and Africa, has made it one of the most invasive species of all time. Even though the biology of Ae. albopictus in its native tropical environment has been documented for a long time, the biology and ecology of this species in newly colonized temperate environments remain poorly known despite its important role as a vector for about twenty arboviruses. In this context, the main goals of this work were to investigate Ae. albopictus phenotypic variations at a local scale in Albania, the country where Ae. albopictus was first recorded in Europe, and to determine if its phenotypes could be affected by altitude. Analysis of Ae. albopictus wing phenotypes was performed using a geometric morphometric approach. We observed shape and size variations among altitudinal populations of Ae. albopictus. Differences of wing phenotypes were highlighted between altitude groups for male and female mosquitoes. The phenotypic variations observed in Ae. albopictus between altitudinal groups indicated these populations are exposed to environmental and ecological pressures. These results suggest the presence of phenotypic plasticity in this species.

Altitudinal differentiation of Quercus robur in Bosnia and Herzegovina

Morphological variation based on eight measured and four derived traits was studied to establish whether there was significant variation between populations and to identify the influence of the altitude on morphological differentiation among 44 natural stands of common oak (Quercus robur L.) in Bosnia and Herzegovina, ranging from 82 to 860 m. The results point to significant intra- and inter-population differences. Elevation-related variation is less pronounced and determined largely by microclimatic factors. The results could provide management strategies for species reintroduction in the study area. There are no differences in leaf morphology between the different branches of individual trees. However, there are important variations between the altitudinal groups and closely linked to environmental factors in all traits. An important recommendation is to use seeds from oak with attention to their altitudinal origin.

The variability of maximum wind gusts in the Czech Republic between 1961 and 2014

ABSTRACTThis contribution employs instrumental records to analyse the temporal and spatial variability of monthly, seasonal and annual maximum wind gusts (MWGs) in the Czech Republic. The development of an observation network capable of measuring wind gusts, the possible technical weaknesses of wind measurements and problems with establishing homogeneity in wind‐gust data are described. For the 1961–2014 period, quality‐checked data from 19 synoptic stations of the Czech Hydrometeorological Institute throughout the territory of the Czech Republic are examined, divided into three altitudinal groups. In terms of the spatial variability of MWGs, correlation coefficients between stations decrease more strongly in relation to station distance rather than altitude. Spatial correlations are better expressed (by higher correlation coefficients) in the winter half‐year than in the summer half‐year. Linear trends in monthly, seasonal and annual MWGs for the 19 synoptic stations, for their three altitudinal groups, and for the entire Czech Republic show statistically significant decreases (deepest in November and autumn), with the exception of spring (for stations above 300 m) and summer. The 10 highest MWG events of all are selected. The spatial distribution of wind gusts for two prominent windstorms, Kyrill (18–19 January 2007) and Emma (1–2 March 2008), are presented. Changes in MWGs series are compared with fluctuations in atmospheric circulation responding to the North Atlantic Oscillation. Decreasing MWG trends are discussed with respect to diminishing storminess and surface wind speeds (wind stilling) recorded during recent decades in Europe, as well as over other continents.

云南花椒园中昆虫群落特征的海拔间差异分析

分析了金沙江畔7个不同海拔区域花椒园中昆虫群落特征的动态变化及其与温、湿度变化的关系。结果表明：花椒园中昆虫群落的多样性、均匀度、丰富度、<em>S</em>_<em>s</em>/<em>S</em>_i、<em>S</em>_<em>n</em>/<em>S</em>_<em>p</em>指标随海拔升高先增加后减少，而个体数、优势集中性指数则随海拔升高先减少后增加；低海拔（450-750 m）区域花椒园中由于总体温度高、湿度低，较高海拔（1300-1550 m）区域总体温度低、湿度高，均不利昆虫群落多样性、均匀度、丰富度、<em>S</em>_<em>s</em>/<em>S</em>_i、<em>S</em>_<em>n</em>/<em>S</em>_<em>p</em>指标的提高和群落的稳定，而中等海拔（750-1300 m）区域的温度、湿度较为适中，昆虫群落的物种数及个体数量均相对较高，昆虫群落多样性、均匀度、丰富度、<em>S</em>_<em>s</em>/<em>S</em>_i、<em>S</em>_<em>n</em>/<em>S</em>_<em>p</em>指标也较高，群落较稳定；相反，低海拔、较高海拔区域花椒园中昆虫群落优势集中性指数较高，而中等海拔区域却相对较低。综合分析表明，海拔高度及温湿度对花椒园昆虫群落特征影响较大，而海拔高度及温湿度的测量和分析较为方便。;<em>Zanthoxylum bungeanum</em> (Rutaceae) is one of the most important economic plants in some areas of China, because <em>Z. bungeanum</em> could be used to mitigate water and soil loss through the reforestation of barren hillsides where cultivation and tree removal has occurred. The mechanisms of insect community dynamics and pest insect outbreaks can be identified through their relationship with environmental factors such as altitude, temperature, humidity and insect community characteristics.<br>This study investigated the relationship between the environmental variables and insect communities in <em>Z. bungeanum</em> gardens near the Jinshajiang River, Yongshan County, Yunnan, China. Insect communities were sampled from seven different gardens at varying altitudes (low 450-750 m; medium 750-1300 m; high 1300-1550 m) from March to September, 2008. All data were analyzed using multivariate analysis of variance (MANOVA) and the level of correlation using the Gray-system theory. The results were: 1) Insect community structure varied with altitude, suggesting altitude is a key factor influencing insect communities in <em>Z. bungeanum</em> gardens; 2) Increases in altitude resulted in higher species diversity, evenness, richness, <em>S</em>_<em>s</em>/<em>S</em>_i (the number of species divided by the number of individuals) and <em>S</em>_<em>n</em>/<em>S</em>_<em>p</em> (the number of natural enemy species divided by the number of phytophagous species) at lower altitudes followed by a decline at higher altitudes. However, the species abundance and dominance indices decreased at lower altitudes then increased at higher altitudes; 3) Where <em>Z. bungeanum</em> gardens grew under more extreme climatic conditions, such as higher temperatures and lower humidity at lower altitudes, or lower temperatures and higher humidity at higher altitudes, there were less diverse insect communities. Thus, insect community characteristics such as species diversity, evenness, richness, <em>S</em>_<em>s</em>/<em>S</em>_i and <em>S</em>_<em>n</em>/<em>S</em>_<em>p</em> indices were lower and more unstable in gardens at lower and higher altitudes. The seasonal dynamics of insect communities at lower and higher altitudes changed more quickly compared with those at medium altitudes. The climatic conditions at the gardens at medium altitudes (750-1300 m) were more suitable for diverse insect communities with ideal temperatures and humidity. Thus, the number of insects at the individual and species level in gardens between 750 and 1300 m (medium altitude) were relatively higher compared with gardens at lower and higher altitudes. The insect communities at medium altitudes indicated better stability based on insect community diversity, evenness, richness, <em>S</em>_<em>s</em>/<em>S</em>_i and <em>S_n/S_p </em>indices, which were higher compared with the other two altitudinal groups. In comparison with the gardens at low and high altitudes, the seasonal dynamics of the insect community at medium altitudes changed slightly; 4) The dominance indices for the insect communities were higher at 450-750 m and 1300-1550 m altitude gardens, but lower in the 750-1300 m gardens. Furthermore, the dominance indices at the low and high altitude gardens showed a more significant change among seasons compared with the medium altitude gardens.<br>Overall, insect community dynamics in <em>Z. bungeanum</em> gardens (Yunnan Province) may be influenced by altitudinal factors such as temperature and humidity, affecting insect species and abundance in various sub-communities. The key influencing factors were the extremes of temperature and humidity. The stability of insect communities in <em>Z. bungeanum</em> gardens could be improved under suitable temperature and humidity conditions similar to those found between 750 and 1300 m.

Genetic differentiation in Pinus brutia Ten. using molecular markers and quantitative traits: the role of altitude

Turkish red pine (Pinus brutia Ten.) is widespread in the eastern Mediterranean Basin. In the late 1970s, four common gardens were established along steep altitudinal transects extending from the coast to about 1,200 m in the Taurus Mountains (Antalya, Turkey). The aim was to study the role of altitude in shaping Turkish red pine genetic diversity and population structure as well as to evaluate the existence of local adaptation along altitudinal gradients in this species. Genetic diversity and population structure were evaluated in replicated altitudinal gradients using chloroplast microsatellite (cpSSR) markers. Genetic differentiation for neutral markers was compared with quantitative differentiation for growth traits for the same populations evaluated at different altitudes. Genetic differentiation among altitudinal groups was higher than among transects. A high portion of the genetic variance corresponded to families within populations (up to 10.75%). Overall quantitative genetic differentiation (Q ST) was higher than molecular differentiation in most test sites for all the traits and ages considered. Turkish red pine shows signatures of local adaptation to environmental gradients related to altitude. For forestry practices, such as selection of seed sources, both altitude and the family level of variation need to be considered.

The subnival–nival vascular plant species of Iran: a unique high-mountain flora and its threat from climate warming

This study provides a first country-wide overview of the vertical distribution patterns and the chorology of vascular plant species that occur in the uppermost elevation zones in Iran. The current distribution patterns are discussed with respect to potential warming-induced species losses. Iran’s subnival and nival vegetation zones are found at elevations above 3600–3900 m in a highly fragmented distribution across Alborz, Zagros, and NW-Iran. Based on literature research and on field observations, all vascular plant species living in the subnival–nival zone of Iranian mountains were identified (151 species) and classified into three altitudinal groups: Group A comprises species that occur mainly in subnival–nival habitats (51 species). Group B are species being common in subnival–nival areas but are equally present in the alpine zone (56 species). Group C are species that can reach to subnival areas but also grow in alpine, subalpine and sometimes lower altitudes (44 species). The chorological patterns differ among the three groups. The percentage of species being endemic to Iran decreases from group A, to B and C, with 68, 53 and 20%, respectively. A narrow altitudinal distribution at high elevations is clearly related to a small-scaled geographical distribution range. The outstanding rate of high-altitude endemism appears to result mainly from orographic isolation of the country’s highly scattered cold areas and by the absence of extensive Pleistocene glaciations. The narrow distribution of most of Iran’s cold-adapted mountain flora and the low potential of alternative cold habitats render it highly vulnerable to climate change.

Altitudinal diversity in horsegram (Macrotyloma uniflorum (Lam.) Verdc.) landraces collected from Himalayan hill region

A total of 54 horsegram landraces collected from three altitudinal zones (lower hills, mid hills and higher hills) of Himalayan region were characterized and evaluated for nine quantitative characters. Accessions collected from lower and higher hills were more diverse and differed significantly from mid hills accessions for characters viz., days to flowering, days to physiological maturity, plant height and grain yield per plant. The plotting of first and second principal component axes scores revealed that there was dispersion among the accessions collected from different altitudinal groups. It reveals a less variability among the landraces collected from same altitudinal group but high variability among the landraces collected from different altitudes. This suggests that the horsegram landraces are adapted to specific zone due to different selection pressure practiced by the farmers at different altitudes. Farmers in lower and higher hills select the landraces having high grain yield coupled with less reproductive phase duration and taller in nature.

Inter simple sequence repeat (ISSR) based analysis of genetic diversity ofLobelia rhynchopetalum(Campanulaceae)

An understanding of the patterns of genetic variation within and among populations of plant species is essential for devising optimum genetic management strategies for their conservation. Here, the inter simple sequence repeat (ISSR) technique was used to study genetic variation of the Afroalpine giant lobelia, Lobelia rhynchopetalum, based on ten populations sampled from Bale and Simen mountains in Ethiopia. The percentage of polymorphic loci across all samples (P(S)) and within population (Pp) was 78% and 27%, respectively. Regardless of a high total genetic variation, the species has quite low variation within populations. All genetic variation analyses revealed higher variation among populations than within populations (G'(ST)= 0.59, G(ST)=0.63, F(ST)=0.58). Analysis of molecular variance (AMOVA) that employed 156 ISSR markers revealed significant variations among populations; among the two mountain systems and among the three altitudinal groups (P < 0.001). The implications of these findings are discussed, especially from conservation point of view.

Changes in Austrian pine forest floor properties in relation with altitude in mountainous areas

Altitudinal studies has become of interest to ecologists concentrated on functional alterations aiming to clarify the effects of limiting factors. Nutrient element release from forest floor (FF) decomposition is suppressed by those factors such as low temperature, shortened vegetation period concluding FF accumulation at high elevation fields. To draw out a response to the FF decomposition issue, FF layers as leaf + fermentation (L + F) and humus (H) were collected from 37 representative sample plots along an altitudinal gradient (from 1,400 m to 1,710 m) on Kaz (Balikesir-Turkey) mountain. Mass, pH, organic matter (OM) and total nitrogen (Nt) contents of FF were investigated to explain the relation between decomposition and altitudinal effects. The results revealed that total FF mass and (L + F), (H) sub-fraction masses through elevation show an insignificant relation with the altitude. No significant difference was found between the altitudinal groups in the OM content of L + F. Besides there are significant negative correlations between OM contents (%) of L + F and H layers and altitude with the coefficient values 0.342 (&lt;I&gt;P&lt;/I&gt;&lt; 0.05) and 0.597 (&lt;I&gt;P&lt;/I&gt; &lt; 0.01), respectively. The Nt content of L + F layer also increases through the elevation revealing a medium correlation with altitude (0.368; &lt;I&gt;P&lt;/I&gt; &lt; 0.05). The increasing Nt and decreasing OM contents show better decomposition rates at higher sites regardless of the altitude induced climatic changes. We assume that the forest floor accumulation under tree canopies provides a better decomposition relying on the microclimatic environment mediated by tree canopies, in spite of the altitude.

Genetic diversity and differentiation of cultivated amochi (Arisaema schimperianum Schott) in Ethiopia as revealed by AFLP markers

Amochi (Arisaema schimperianum Schott) is an off-season crop plant in southern Ethiopia, grown during the dry season on residual moisture, for its edible tubers. It has gained importance as a "security crop" especially during the years of moisture stress and food shortage. Amochi is irritating in contact to the skin. Removal of this effect is an important question for breeding. As the first step, however we attempt to establish base line information of its breeding system and genetic variability using AFLPs. The extent of genetic differentiation among 11 populations (96 individuals) of amochi sampled along altitudinal gradients that varied from 1700 to 3200 m a.s.l. was investigated. The populations were classified in to three altitudinal groups: lowland (1700 to 2200 m a.s.l.), central-highland (2201 to 2600 m a.s.l.) and highland (2601 to 3200 m a.s.l.). Polymorphic loci (167) scored from four primer pair combinations, were used for principal component analysis (PCA), and analysis of molecular variance (AMOVA). Both PCA and unweighed pair group with arithmetic mean (UPGMA) clearly differentiated populations into their respective altitude groups, with large genetic distances. AMOVA analysis revealed 70.5%, 16.7% and 12.8% variability between altitude groups, between populations and within populations respectively. Average diversity indices within populations were also low. Since the largest proportion of variation is located between altitude groups, rather than within populations, we suggest future studies on the chemical composition, low irritation, and other desirable traits should consider populations from different altitude ranges.