Maia Akhalkatsi

Recent Plant Diversity Changes on Europe’s Mountain Summits

Climb Every Mountain Mountaintop floras across Europe appear to be responding to climatic change in terms of upslope species range shifts. Pauli et al. (p. 353) systematically analyzed data gathered from standardized permanent plots on 66 high-mountain environments across Europe. On average, mountaintop species numbers have increased significantly during the last decade. However, this increase is a net effect of gains and losses, with losses particularly affecting mountains of Mediterranean regions and their endemic species. This turnover is largely consistent with model predictions and indicates that high-altitude species, and in particular the rich endemic alpine flora of many Mediterranean mountain ranges, will come under increasing pressure in the predicted warmer and drier climates in this region. European mountaintop flower species richness is increasing on northern summits but decreasing on southern summits. In mountainous regions, climate warming is expected to shift species’ ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe’s major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras’ species richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (–1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region.

Facilitation of Seedling Microsites by Rhododendron caucasicum Extends the Betula litwinowii Alpine Treeline, Caucasus Mountains, Republic of Georgia

ABSTRACT In the Central Greater Caucasus Mountains, Georgia, Betula litwinowii (birch) occurs on north-facing slopes of east-west ridgelines that extend upward to high mountain peaks, forms the alpine timberline at higher elevation, and reaches its highest treeline limit only when associated with the broadleaf evergreen shrub, Rhododendron caucasicum. This association might generate an ecological facilitation of either temperatures or sky exposure, both of which have been related to the altitudes at which timberlines/treelines occur. At the lowest site (2072 m) the greatest abundance of birch seedlings (up to 2.3 seedlings/m2) occurred at shaded microsites beneath the B. litwinowii overstory and along shaded north-facing walls of polyhedral soil depressions just beyond this treeline. These seedling microsites also had substantially colder air and soil temperature regimes than more sun-exposed microsites. Similarly, at the highest elevation site (2512 m) the second greatest seedling abundance (0.73 seedlings/m2) occurred in the shaded understory beneath R. caucasicum. Moreover, these microsites had the coldest minimum air and soil temperatures (−1.3°C at 5 cm depths), along with the greatest number of days (40) with minimum soil temperatures <5°C recorded for the measurement period (11 July to 25 October 2003). In addition to the lowest number of seedlings, the more sun-exposed microsites at all sites also had the greatest percent (28–32%) of red leaves per plant, indicative of high concentrations of photoprotective anthocyanins. Thus, reduced sky exposure, and not cold temperature effects, was associated with greater seedling abundance and fewer red leaves per seedling, despite colder temperature regimes. Thus, facilitation of B. litwinowii seedling establishment by the R. caucasicum overstory appeared to extend the maximum altitude of the Betula treeline via reductions in sunlight exposure, despite lower temperatures.

Characterizing Betula litwinowii seedling microsites at the alpine-treeline ecotone, central Greater Caucasus Mountains, Georgia

Abstract Seedling establishment is an important factor dictating the altitudinal limits of treeline species. Factors which affect seedling mortality and survival, however, have yet to be fully characterized, especially for deciduous treeline species. Here we describe microsite characteristics of successfully established Betula litwinowii seedlings at the alpine-treeline ecotone. Possible harmful effects of sky exposure on seedling physiology (i.e. photoinhibition of photosynthesis) were also examined, as well as possible facilitative effects of co-occurring Rhododendron caucasicum shrubs on northern slopes and microtopographical depressions (mainly watercourses) in ridgetop meadows. On northern slopes, seedling density was highest in newly exposed soils, with 90% of the youngest seedlings (<2 cm) occurring in patches of rocky, bare, or moss-covered soils within the Rhododendron thicket. R. caucasicum was not a significant source of shade for B. litwinowii, as most seedlings were established 0.25–0.5 m away from the nearest shrub, and shade cover generated by R. caucasicum was observed in only 1% of seedlings at midday. On ridgetops, density of B. litwinowii was sixfold higher inside microtopographical depressions compared to outside. Sky exposure of seedlings within depressions was similar to northern slopes, ranging from 50% to 87%. Across all microsites, seedlings were most abundant under 70–87% sky exposure. This preference for open microsites, combined with the observation that sustained photoinhibition of photosynthesis (Fv/Fm < 0.65) was observed only in the most open microsites (i.e. >80% sky exposure), suggests that sky exposure is likely not a significant factor affecting seedling mortality in B. litwinowii, in contrast to results reported for conifer and broadleaf evergreen species at treeline. A higher photosynthetic capacity and a deciduous life history may provide both tolerance and avoidance to the physiological stresses associated with high sky exposure for B. litwinowii seedlings, and other factors, such as soil moisture, more likely account for successful establishment within microtopographical depressions and R. caucasicum thickets.

Diversity and Genetic Erosion of Ancient Crops and Wild Relatives of Agricultural Cultivars for Food: Implications for Nature Conservation in Georgia (Caucasus)

The problem of genetic erosion of landraces and their wild relatives needs active contributions by national policies and comprehensive measures are urgently needed to avoid the complete loss of ancient crop genetic resources in Georgia. International nature conservation institutions and Georgian scientific and nongovernmental organizations should show more activity to the restoration of ancient crops, which defined the healthy life of Georgians

Reasons and Processes Leading to the Erosion of Crop Genetic Diversity in Mountainous Regions of Georgia

Abstract Agriculture has a long history in Georgia; it has led to a great variety of ancient crops. However, this diversity is under threat for many reasons. First, introduced crops have caused a loss of traditional cultivars, because the introduced crops are preferred due to their higher yield. Moreover, agricultural machines such as forage and grain combine harvesters imported to Georgia are constructed for widely distributed, imported crops and cannot be used to harvest local cultivars. Until recently, genetic erosion of ancient crop varieties was not a problem in the mountain areas of Georgia, which until the 1990s constituted a depository of local crop varieties of wheat, barley, rye, oat, common millet, traditional legumes, vegetables, herbs, and spice plants with specific varieties adapted to mountain conditions. These mountain areas worked as a depository because local mountain communities preserved their traditional ways of life and socioeconomic structures. Their traditional agricultural equipment, used on a large scale until the 1990s, still allows them to maintain areas under cultivation (with grain or other crops) on steep slopes and at high elevations where modern tractors cannot be used. Moreover, some old landraces of wheat and barley are still being used to prepare bread and beer for religious rituals. Currently, many endemic and native representatives of crop plants are in danger of extinction. International nature conservation institutions and Georgian scientific and nongovernmental organizations have developed plans to preserve the genetic resources of local cultivars.

Biotope Types of the Treeline of the Central Greater Caucasus

Some characteristics (habitat, distribution, characteristic species, ecological importance, practical use and danger factors) are given of 17 typical treeline biotopes in the Kazbegi region, situated on the north-facing macro slope of the central part of the Main Watershed Range of the Greater Caucasus. The diversity of species composition is mainly due to peculiar structural properties of the vegetation of these biotopes, rather than ecological (altitude, moist or dry conditions,) and anthropogenic (grazing, haymaking) factors. The majority of the studied biotopes are referred to the II stage of hemeroby, but untouched shrub communities (dominated by Rhododendron caucasicum), elfin crookedstemmed birch forests (dominated by Betula litwinowii) and fragments of tall herbaceous vegetation should be referred to the I stage of hemeroby (natural and close to natural). Current global climate change will cause the most drastic changes in moist (tall herbaceous vegetation), snowline (humid broad-leaved meadows dominated by Trollius ranunculinus), broad-leaved mesophilous meadows (dominated by Anemone fasciculata), elfin crookedstemmed birch forest and scrub biotopes. The numerous biotopes are characterized by high sensitivity, which is caused by the following factors: landscape mainly devoid of forests, high degree of relief and, consequently, bare soil cover, low and unstable snow cover, frequent solifluction, etc. The following biotopes should be regarded as priority habitat types: tall herbaceous vegetation, scrub and elfin crooked-stemmed birch forest.

Erosion and Prevention of Crop Genetic Diversity Landraces of Georgia (South Caucasus)

Georgia (South Caucasus) has many ancient crop varieties used with very old farming traditions and owns linguistics of old civilization coinciding with early Neolithic epoch. The traditional landraces used by local people for thousands of years affected the health and human longevity of individuals in the Georgian population predicting adaptation to healthy food. Crop domestication is associated to existence of crop wild relatives (CWRs) on the territory of Georgia. Molecular studies confirmed domestication of grapevine (Vitis vinifera) from wild species (V. vinifera subsp. sylvestris) and pear varieties from wild Caucasian pear (Pyrus caucasica). Many fruits are associated to wild tree species distributed in the refugium territory of the western Georgia. Some crops: wheat, barley, ray, oats, lentil, pea, chickpea, etc., are genetically related with wild species. Therefore, the most important challenges in the near future are certainly the molecular characterization of germplasm collections for preserving them from genetic erosion and the identification of phenotypic variants potentially useful for breeding new varieties. Georgian ancient crop varieties reveal a high level of adaptation to local climatic conditions, and often have high resistance to diseases. The loss of landraces and ancient crop varieties should be considered as main threat to agrobiodiversity in Georgia. Besides the diminishing of the amount of agricultural products, the main threat to agrobiodiversity is the loss of the territory of Georgia. Additionally, there are several reasons for the genetic erosion of the ancient cultivars and the wide distribution of new varieties of introduced crops. Germplasm of the landraces extinct in the local farms are stored only in the gene banks and in the living collections of Georgia and foreign countries. One of the problems is the deficit of information about the current state of ancient crops and recommendations for their conservation are inadequate. Therefore, it is necessary to assess research needs and implications for protection of genetic resources and to formulate recommendations for the conservation and on-farm maintenance of Georgian landraces.

Plant species composition and diversity on the calcareous soils in around of the limestone quarry in Georgia, Caucasus region

The information for educational working was collected from literature data and during field trips. The field work was carried out using phytosociological methods of plot recording. Plant species composition and diversity was determined for each habitat. Statistical analysis of these data gave a possibility to develop complete database information about species diversity changes among succession stages of vegetation recovery. The obtained data demonstrates the role of phytosociological investigation in determination of plant species used for re‒vegetation process during post‒closed rehabilitation of limestone quarry.1 Preliminary study carried out in summer 2012 in Georgia in the framework of the program “the Quarry Life Award” used for the education working two limestone quarries‒Kavtiskhevi and Dedoplistskaro.1

Ancient Crops Continuing for an Extended Period in Samtskhe-Javakheti Region of Georgia – a Review

Introduction Georgian territory (69.700 km2) covers both mountain ranges between 40o and 47o latitude east, and 42o and 44o longitude north. The Caucasus mountain system was formed ca. 28.5–23.8 million years ago as the result of a tectonic plate collision between the Anatolian and Arabian plate moving northward and the Eurasian plate. Georgia is a mountainous country made up of two separate mountain systems: the Greater Caucasus Mountain Range, lying northwest to east-southeast between the Black Sea and Caspian Sea; and the Lesser Caucasus Mountains, which run parallel to the greater range, at a distance averaging about 100 km south. It is made up of two separate mountain systems: the Greater Caucasus mountain range lying north-west to east-southeast between the Black Sea and Caspian Sea; and the Lesser Caucasus Mountains, which run parallel to the greater range, at a distance averaging about 100 kilometres south. Two thirds of the country is mountainous with an average height of 1200 m.a.s.l., with highest peaks of Mount Shkhara (5184 m.a.s.l.) at the Western Greater Caucasus and Mount DidiAbuli (3301 m.a.s.l.) in the Lesser Caucasus [1-3].

Situational Analyses of the Current State of Plant Genetic Resources Important for Food and Agriculture in Georgia (Caucasus Ecoregion)

Conservation of the genetic resources of ancient crops in Georgia are current landraces and primitive forms occurring in Georgia and to publish lists of indigenous landraces and CWRs of cereals, legumes, vegetables, vine and fruits representing direct ancestors, and endemic, rare or endangered species. National policies and comprehensive measures are urgently needed to address the problem of conserving the genetic resources of ancient crops in Georgia. It is necessary to establish a general overview of the types of crops that are current landraces and primitive forms occurring in Georgia. However, the introduction of new parasites has revealed that endemic forms of Georgian crop plants contain valuable selective disease-resistant material for genetic engineering. Establishment and maintenance of ex situ collections and databases should be considered just as a first step in the conservation process of ancient crop varieties. Storage of the ex situ collections should be improved through upgrading the present storage of the field crop genebank facilities.