Open Steppe Research Articles

Palaeolithic occupation of the Anatolian High Plateau during a cold period: An MIS 6 aged artifact from the Avlamış Valley, Eskişehir, NW Turkey

AbstractIn the Avlamış Valley, 10 km north of Eskişehir (NW Anatolia), an undamaged triangular Levallois flake was encountered in a paleosol, 430 cm beneath the ground surface. The artifact has a minimal dorsal retouch on the right margin, and there is a light beige partial patina on the ventral surface. Based on the technological investigations, this artifact was made using the centripetal recurrent Levallois technique. An observation of the trench walls revealed the triple nature of the stratigraphy: an upper gravelly sand (Unit‐1), an underlying reddish‐brown pebbly paleosol (Unit‐2), and a lowermost dominantly pink, finer‐grained deposit (Unit‐3) where the artifact was retrieved. Optically stimulated luminescence ages indicate a strong influence of global marine isotopic stages (MIS) on the trench stratigraphy, with the deposit hosting the artifact dating to 148 ± 20 ka (MIS 6 cold period). The available pollen data from the same stratigraphic level verified an open steppe landscape with some arboreal plant cover during deposition. This is the first stratigraphically dated Middle Palaeolithic artifact from NW Anatolia, and one of the few in the whole country, thus igniting further discussion about the ways Pleistocene hominins adapted to cold and arid environmental conditions.

Restoration prioritization for industrial area applying multiple potential natural vegetation modeling

Scaling‐up ecological restoration demands the involvement of private sector actors. Experience regarding science‐based habitat restoration programs in the sector should be made available to support further joint projects. In our case, hierarchical restoration prioritization was applied to select best target for habitat reconstruction at a Hungarian industrial area. Multiple potential natural vegetation model, a novel approach, supported restoration prioritization satisfying both ecological (sustainability and nature conservation value) and other needs (feasibility, rapid green surface, amenity, and education value). The target that met all priorities was the open steppe forest that has a mosaic arrangement with open and closed sand steppes. The potential area of this xero‐thermophile oak wood is expected to expand in Hungary with climate change, therefore the selected target has a likelihood of long‐term sustainability, if established. A matrix of sand steppes was created first at the factory area in 2014–2015, and tree and shrub saplings were planted in this matrix. The seeding induced rapid changes in vegetation composition: the second year samples became close to reference sand steppes in the principal component analysis ordination space. Tree and shrub survival was species dependent, reaching a maximum of 52 and 73% for tree and shrub species, respectively. One tree and 2 shrub species did not survive at all. Altogether 53 of 107 target species have established. So far, restored vegetation development confirmed the suitability of the applied hierarchical prioritization framework at factory scale.

Environmental dynamics of the Baraba forest-steppe (Siberia) over the last 8000 years and their impact on the types of economic life of the population

This article offers a reconstruction of the vegetation and climate of the south-western Siberian Baraba forest-steppe area during the last ca. 8000 years. The analysis of palynological data from the sediment core of Lake Bolshie Toroki using quantitative methods has made it possible to reconstruct changes of the dominant types of vegetation and mean July air temperatures. Coniferous forests grew in the vicinity of the lake, and mean July air temperatures were similar to present-day ones between 7.9 and 7.0 kyr BP. The warmest and driest climate occurred at 7.0–5.0 kyr BP. At that time, the region had open steppe landscapes; birch groves began to spread. A cooling trend is seen after 5.5 kyr BP, when forest-steppe began to emerge. Steppe communities started to dominate again after 1.5 kyr BP. Mean July air temperatures lower than now are reconstructed for the period of 1.9–1 kyr BP, and then the temperatures became similar to present-day ones. Comparing the archaeological data on the types of economy of the population which inhabited the Baraba forest-steppe with the data on changes in the natural environment revealed a connection between the gradual transition from hunting and fishing to livestock breeding and the development of forest-steppe landscapes with a decrease in the area covered by forests. The development of the forest-steppe as an ecotonic landscape starting around 5 kyr BP might have contributed to the coexistence of several archaeological cultures with different types of economy on the same territory.

Avian electrocution rates associated with density of active small mammal holes and power-pole mitigation: Implications for the conservation of Threatened raptors in Mongolia

Avian electrocution at power lines is a well-documented phenomenon, yet factors influencing the frequency of electrocution events and the efficacy of mitigation techniques remain relatively under-reported. During May-July, we surveyed a 56km long 15kV electricity distribution line running across open steppe in Mongolia recording electrocuted birds of prey under the power poles. We recorded high rates of electrocution of several Threatened raptor species, particularly the Endangered Saker Falcon Falco cherrug, which was killed at a monthly rate of 1.6 birds per 10km during the period of our study. Electrocution frequency at line poles was associated with density of small mammal holes and the deployment of mitigation measures. It is likely that local prey abundance influences the frequency of birds of prey perching on power poles, which is consequently reflected in electrocution rate. We evaluated the efficacy of mitigation measures and found that the use of perch deflector spikes on the crossarms of line poles reduced electrocution rates when 3 or 4 spikes were deployed. Perch deflectors probably worked by reducing the opportunity for birds to perch adjacent to pin insulators rather than by reducing the frequency of birds perching on the crossarm per se. At anchor poles, reconfiguration of jump wires at two phases, so they passed under the crossarm rather than over, significantly reduced electrocution rates. These mitigation measures potentially represent a relatively inexpensive method to reduce the frequency of raptor electrocution events in regions where cost is a key factor for power line managers in determining whether or not any form of mitigation is used.

Pupilla alluvionicaMeng & Hoffmann, 2008: A Land Snail Extant in the Altai Refugium Recognised for the First Time in Central European Early-Middle Pleistocene Glacials

Pupilla alluvionica Meng & Hoffmann, 2008 is an extant land snail species known until now only from a few sites in the Russian Altai Mountains. We have now identified it in fossil loess assemblages of Early-Middle Pleistocene age at three Central European sites. Fossil materials match those of Altaian populations, being only slightly smaller in mean shell width. In addition to the details of the locations and biometrics of these fossil finds, we list the faunas associated with P. alluvionica in the deposits. These are compared with the ecological conditions and associated faunas of living populations from the Altai. Pupilla alluvionica is a typical inhabitant of xeric habitats: steppes with rocky limestone outcrops. This matches the known habitat preferences of associated species in the fossil deposits that are typical of open loess steppe.

Vegetation responses to abrupt climatic changes during the Last Interglacial Complex (Marine Isotope Stage 5) at Tenaghi Philippon, NE Greece

The discovery that climate variability during the Last Glacial shifted rapidly between climate states has intensified efforts to understand the distribution, timing and impact of abrupt climate change under a wide range of boundary conditions. In contribution to this, we investigate the nature of abrupt environmental changes in terrestrial settings of the Mediterranean region during the Last Interglacial Complex (Marine Isotope Stage [MIS] 5) and explore the relationships of these changes to high-latitude climate events. We present a new, temporally highly resolved (mean: 170 years) pollen record for the Last Interglacial Complex from Tenaghi Philippon, north-east Greece. The new pollen record, which spans the interval from 130,000 to 65,000 years ago, forms part of an exceptionally long polleniferous sediment archive covering the last 1.35 million years. The pollen data reveal an interglacial followed by alternating forest and steppe phases representing the interstadials and stadials of the Early Glacial. Superimposed on these millennial-scale changes is evidence of persistent sub-millennial-scale variability. We identify ten high-amplitude abrupt events in the pollen record, characterised by rapid contractions of closed forest to open steppe environment and interpreted to indicate major changes in moisture availability and temperature. The contractions in forest cover on millennial timescales appear associated with cooling events in the Mediterranean Sea, North Atlantic and Greenland regions, linked to the Dansgaard-Oeschger (DO) cycles of the Early Glacial. On sub-millennial timescales, the pattern of changes in forest cover at Tenaghi Philippon display a structure similar to the pattern of short-lived precursor and rebound-type events detected in the Greenland ice-core record. Our findings indicate that persistent, high-amplitude environmental variability occurred throughout the Early Glacial, on both millennial and submillennial timescales. Furthermore, the similarity of the pattern of change between Tenaghi Philippon and Greenland on sub-millennial timescales suggests that teleconnections between the high-latitudes and the Mediterranean region operate on sub-millennial timescales and that some terrestrial archives, such as Tenaghi Philippon, are particularly sensitive recorders of these abrupt climate changes.

Landscape evolution and agro-sylvo-pastoral activities on the Gorgan Plain (NE Iran) in the last 6000 years

The Gorgan Plain (NE Iran) is characterized by fertile soils formed on a loess plateau and is at present primarily exploited for intensive agriculture. However, the timing and intensity of the human impact on the landscape in the past are still unclear. A sediment core, taken from the centre of the eastern Gorgan Plain in the Kongor Lake covering the major part of the Holocene from 6.1 to 0.8 ka (all ages are calibrated before present), has been studied for pollen, non-pollen palynomorphs, botanical macroremains, insects, charcoal, geochemistry, biomarkers and magnetism in order to provide new insights into the evolution of the landscape and to estimate the intensity of human activities. The data obtained suggest a dry period between 5.9 and 3.9 ka and an increase in regional humidity afterwards with a maximum between 2.7 and 0.7 ka, during the period of the Persian empires (Achaemenid through Sasanian) and the Islamic era. The eastern part of the Gorgan Plain was characterized by open steppe landscapes during the last 6 ka, which most likely were used for pasture and at least since 2.7 ka for agriculture including arboriculture. The strongest anthropogenic impact on the environment around the Kongor site is documented during the Parthian and Sasanian Empires (200 BC–651 AD) and the Islamic era up to the eve of the Mongol invasion.

Holocene cold storage practices on the eastern Snake River Plain: A risk-mitigation strategy for lean times

Previous archaeological research in southern Idaho has suggested that climate change over the past 8000years was not dramatic enough to alter long-term subsistence practices in the region. However, recent isotopic analyses of bison remains from cold storage caves on the Snake River Plain contest this hypothesis. These results, when examined against an archaeoclimate model, suggest that cold storage episodes coincided with drier, warmer phases that likely reduced forage and water, and thus limited the availability of bison on the open steppe. Within this context we build a risk model to illustrate how environment might have motivated cold storage behaviors. Caching bison in cold lava tubes would have mitigated both intra-annual and inter-annual food shortages under these conditions. Our analysis also suggests that skeletal fat, more than meat, may have influenced the selection, transport and storage of bison carcass parts. Deciphering when and how cold storage caves were utilized can ultimately provide a more comprehensive understanding of foraging behaviors in a broad range of hunting-gathering economies.

Las Quemas Rockshelter: Understanding Human Occupations of Andean Forests of Central Patagonia (Aisén, Chile), Southern South America

Hunter-gatherer occupations of the forests of Patagonia are still not well understood compared to those of the open steppe and the coasts. The paucity of forest sites with a thorough chronological framework and the incomplete picture of climate-human dynamics in such environments pose a challenge to understanding the occupations of such habitats. This paper presents recent work at the Las Quemas rockshelter, an archaeological site located in the Andean forests of the Aisén region (44°38’ S) dating between 6100 and 2400 cal B.P. We examine the context of the site, its rock art, and the technological and functional dimensions of its lithic assemblage. By comparing these records with local environmental reconstructions that report forest area fluctuations after the Post-Glacial period, this study provides novel data for a comprehensive regional-scale model of human occupations in central Patagonian forests. Following an initial mid-Holocene occupation, recurring occupational events at the site coincide with a significant contraction of forested area in the region during the late Holocene. The results are discussed in regard to regional archaeological data and current models of forest occupation in Patagonia.

A Harkány-Nagynyárádi-sík zárt lösztölgyesei (Pulmonario mollis-Quercetum roboris Kevey 2008)

The study deal with the phytosociological charac-teristics of oak forests growing on the loess-covered hills on the Harkány-Nagynyárád plain, where the author found rep-resentative stands of a recently described community, the closed pedunculate oak forest on loess (Pulmonario mollis-Quercetum roboris). This community occupies xero-mesic habitats between the more xeric habitat of the open steppe woodland (Aceri tatarici-Quercetum roboris) and the mesic habitats of the closed oak-hornbeam forest (Corydali cavae-Carpinetum). In terms of its ecological role, this community is the ecological equivalent of the closed pedunculate oak forest on calcareous sand (Convallario-Quercetum roboris). In the closed pedunculate oak forest, character species of dry grasslands (Festuco-Brometea, Festucetalia valesia-cae, Festucion rupicolae, etc.) play a subordinate role as opposed to the open steppe woodland, in which these spe-cies are prevalent. Unlike the open steppe woodland, the community harbors a number of mesic species (Querco-Fagetea, Fagetalia, Carpinenion) in the understorey, owing to the xero-mesic character of its habitat. It is separated from the often adjoining stands of closed oak-hornbeam forest, which grows at the bottom of the valleys, by the oc-currence of species characteristic of dry oak woods (Quer-cetea pubescentis-petraeae, Quercetalia cerridis, Aceri tatarici-Quercion), and the absence of several mesic spe-cies (Querco-Fagetea, Fagetalia, Carpinenion) typical in the oak-hornbeam forest. This community is thus classified as a member of the Polygonato latifolio-Quercenion roboris Kevey 2008 suballiance.

Into Tibet: An Early Pliocene Dispersal of Fossil Zokor (Rodentia: Spalacidae) from Mongolian Plateau to the Hinterland of Tibetan Plateau.

This paper reports the fossil zokors (Myospalacinae) collected from the lower Pliocene (~4.4 Ma) of Zanda Basin, southwestern Tibet, which is the first record in the hinterland of Tibetan Plateau within the Himalayan Range. Materials include 29 isolated molars belonging to Prosiphneus eriksoni (Schlosser, 1924) by having characters including large size, highly fused roots, upper molars of orthomegodont type, m1 anterior cap small and centrally located, and first pair of m1 reentrants on opposing sides, high crowns, and high value of dentine tract parameters. Based on the cladistics analysis, all seven species of Prosiphneus and P. eriksoni of Zanda form a monophyletic clade. P. eriksoni from Zanda, on the other hand, is nearly the terminal taxon of this clade. The appearance of P. eriksoni in Zanda represents a significant dispersal in the early Pliocene from its center of origin in north China and Mongolian Plateau, possibly via the Hol Xil-Qiangtang hinterland in northern Tibet. The fast evolving zokors are highly adapted to open terrains at a time when regional climates had become increasingly drier in the desert zones north of Tibetan Plateau during the late Miocene to Pliocene. The occurrence of this zokor in Tibet thus suggests a rather open steppe environment. Based on fossils of large mammals, we have formulated an “out of Tibet” hypothesis that suggests earlier and more primitive large mammals from the Pliocene of Tibet giving rise to the Ice Age megafauna. However, fossil records for large mammals are still too poor to evaluate whether they have evolved from lineages endemic to the Tibetan Plateau or were immigrants from outside. The superior record of small mammals is in a better position to address this question. With relatively dense age intervals and numerous localities in much of northern Asia, fossil zokors provide the first example of an “into Tibet” scenario–earlier and more primitive taxa originated from outside of the Tibetan Plateau and the later the lineage became extinct in southwestern Tibet.

The large mammals of North-Minusinsk basin in the Last Glacial period

Twenty five species of large mammals are reliably established for the North-Minusinsk basin in the Last Glacial period. Another nine species of large mammal remains whose regular habitation is questionable are also known. The species biodiversity of mammals of open steppe landscapes is three times higher than the biodiversity of animals of closed and semi-closed forest biotopes. Species of closed and semi-closed forested landscapes are dominant in the modern fauna of the region. Most of the species who lived in open landscapes of the region became extinct. A possible reason for the extinction of large representatives of the mammoth fauna is the reduction of their migration ability. As a result of reduction of the area steppe landscapes beyond the depression, migration routes of large representatives of the mammoth fauna were disrupted. The steppe phytocoenoses, preserved in the territory of Minusinsk depression to the present, were not able to maintain the stability of the mammoth fauna. This may have led to the extinction of large animals. However, the stability of steppe ecosystems in the region promoted the preservation of most micro-mammals, as well as the later extinction of some large mammals in the region.

Small mammals from the Strashnaya cave (Northwest Altai, West Siberia, Russia)

A sequence of small mammal associations has been studied from the Paleolithic site of Strashnaya cave (Altai Mountains, West Siberia, Russia). The total faunal composition includes 45 species of rodents, bats, insectivores, and lagomorphs. The dominant groups in each of 10 layers that included small mammal remains are rock voles, grey voles and zokors. Co-dominating groups are ground squirrel, marmots, steppe lemmings, and red-backed voles. Small mammals from the Strashnaya cave indicate that during Late Pleistocene winters in the region could have been warmer than now. They also suggest highly mosaic biotopes around the cave in Late Pleistocene that includes open steppe, desert, floodplain, and forest. Small mammals show open areas such as steppes, floodplain and meadows in the early Holocene. The modern small mammal fauna confidently indicate taiga forest environments.

Měkkýši Národní přírodní rezervace Karlštejn v Českém krasu [Molluscs of the Karlštejn National Nature Reserve in the Bohemian Karst

This paper brings findings of recent malacological research (2013) and earlier mostly unpublished data about malacofauna of the Karlštejn National Nature Reserve (abbreviated as NNR) (Czech Republic, Central Bohemia, Bohemian Karst Protected Landscape Area). A total of 89 mollusc species (76 terrestrial snails, 5 freshwater snails, 8 bivalves) were recorded. The mollusc fauna of the NNR represents 35% of the total of 251 mollusc species found in the Czech Republic. The studied area comprises of very diverse habitat types with various and rich mollusc communities. Forest snails are dominating (38%) followed by species of the open steppes (27%). 28 species belong to endangered Red List species of the Czech Republic. Critically endangered Helicopsis striata and endangered Chondrina avenacea, Truncatellina claustralis and Zebrina detrita belong to the species of dry and open habitats. Helicopsis striata is probably extincted in most of localities in the Bohemian Karst. Its presence in the NNR was not confirmed. Bohemian Karst holds most of populations of Chondrina avenacea in the Czech Republic and the most of findings are situated in the Karlštejn NNR. Zebrina detrita inhabits here isolated site in Bohemia, where it was probably introduced in the past. Four new sites of the Holocene optimum relict Truncatellina claustralis were found.

Human subsistence and environmental stability during the last 2200 years in Epullán Chica cave (northwestern Patagonia, Argentina): A perspective from the zooarchaeological record

The faunal content from Epullán Chica archaeological site (ECh, thereafter), a small cave located in northwestern Patagonia, Argentina, was studied from taphonomic and paleoenvironmental points of view. This cave is placed in the ecotone between Monte desert and the Patagonian steppe, in the middle Limay River basin, was occupied since the end of the Late Holocene. Zooarchaeological evidence retrieved from ECh is diverse, including fresh-water mollusk shells (Diplodon chilensis), eggshell and bone fragments of Rheidae, bones and teeth of large (Lama guanicoe), medium (e.g., Chaetophractus villosus, Conepatus chinga), and micro-sized (several species of sigmodontine and caviomorph rodents) mammals. Most of the recorded taxa were the result of human exploitation. However, owl pellets preserved in the sediments, and other taphonomic signatures, clearly indicate that avian predators are responsible for part of the micromammal record. Micromammal abundances during the last 2.2 ka BP are suggestive of a relative environmental stability around ECh, at least until the beginning of the last century. In this sense, Late Holocene landscapes were dominated by open steppe areas and large rocky outcrops, with minor changes in humidity and temperature during this period.

European bison as a refugee species? Evidence from isotopic data on Early Holocene bison and other large herbivores in northern Europe.

According to the refugee species concept, increasing replacement of open steppe by forest cover after the last glacial period and human pressure had together forced European bison (Bison bonasus)—the largest extant terrestrial mammal of Europe—into forests as a refuge habitat. The consequent decreased fitness and population density led to the gradual extinction of the species. Understanding the pre-refugee ecology of the species may help its conservation management and ensure its long time survival. In view of this, we investigated the abundance of stable isotopes (δ13C and δ15N) in radiocarbon dated skeletal remains of European bison and other large herbivores—aurochs (Bos primigenius), moose (Alces alces), and reindeer (Rangifer tarandus)—from the Early Holocene of northern Europe to reconstruct their dietary habits and pattern of habitat use in conditions of low human influence. Carbon and nitrogen isotopic compositions in collagen of the ungulate species in northern central Europe during the Early Holocene showed significant differences in the habitat use and the diet of these herbivores. The values of the δ13C and δ15N isotopes reflected the use of open habitats by bison, with their diet intermediate between that of aurochs (grazer) and of moose (browser). Our results show that, despite the partial overlap in carbon and nitrogen isotopic values of some species, Early Holocene large ungulates avoided competition by selection of different habitats or different food sources within similar environments. Although Early Holocene bison and Late Pleistocene steppe bison utilized open habitats, their diets were significantly different, as reflected by their δ15N values. Additional isotopic analyses show that modern populations of European bison utilize much more forested habitats than Early Holocene bison, which supports the refugee status of the species.

Vegetation and climate in the eastern Iberian Peninsula during the pre-evaporitic Messinian (late Miocene). Palynological data from the Upper Turolian of Venta del Moro (Spain)

The present paper reports a complete palynological study of the Upper Turolian sediments outcropping at the Venta del Moro site (eastern Iberian Peninsula). The pollen assemblages observed mainly reflect the local and regional vegetation, which must have formed part of a wetland ecosystem within a general setting of open steppe, as indicated by the great abundance and diversity of herbaceous pollen. This reflects the persistence of open vegetation in the Iberian Peninsula after the Middle Miocene when it became extensive. We here report the most recent record of Disanthus for the Iberian Peninsula. This shrub played an important role in an unusual, edaphically-mediated vegetation linked to lacustrine–palustrine or riparian shore conditions. A shift in the water level led to a flooding episode, extending wetland and causing a drastic reduction in Disanthus and Amaranthaceae. The results of quantitative (multivariate and coexistence) and semi-quantitative (integrated plant record) analyses of the pollen dataset support these interpretations of the palaeovegetation and provide insight into the regional palaeoclimate. Stable climatic conditions would appear to have reigned before the onset of the Messinian salinity crisis. The palynoflora of Venta del Moro is compared with counterparts in other areas of the Mediterranean Basin.

BIOLOGICAL ACTIVITY OF SOILS OF ECOTONE COMMUNITIES’ TAMARISK THICKETS OF NORTHWEST CASPIAN

In the article results of comparative estimation of soil biological activity indicators on the basis of studying intensity of vegetative organic and cellulose decomposition and also oxygen consumption in zone of shrubby thickets and open steppe of West Caspian are given. Rates of vegetative organic decomposition in soils of experience sites have made 5,23 and 5,67 mg·g -1 ·24 h -1 and didn't differ on sites. Intensity of cellulose decomposition in open site was above and has made 6,02 mg·g -1 ·24 h -1 against 4,16 mg·g -1 ·24 h -1 in soil of site with shrubby thickets. The estimation of intensity soil oxygen consumption hasn't shown an essential difference on sites.

Climatic effects on plant species distribution within the forest–steppe ecotone in northern China

AbstractQuestionsAs a narrow belt extending from the northern to the southern edges of the temperate forest zone, there is not only a strong temperature gradient and a long geographic distance but also a very sharp precipitation gradient in the temperate forest–steppe in northern China at a regional scale. Patches of forest are scattered in the steppe matrix. At the local scale, each forest patch shows a climatic gradient from patch centre to its edge and to the open steppe. How do these climatic gradients determine plant species distribution for the forest and steppe within this ecotone?LocationThe temperate forest–steppe ecotone in northern China.MethodsSpecies were recorded in paired plots of forest and steppe at 68 sites. t‐tests were conducted to show differences in floristic composition among forest types. Mantel tests were applied to correlate site‐level floristic distances with geographic and climatic distances for forest and steppe separately as well as for their combination. Floristic differences between paired plots of forest and steppe at each site were correlated to MAT, MAP and geographic factors at that site.ResultsThere was no significant floristic difference in the understorey of forests dominated by Betula platyphylla, B. dahurica or Populus davidiana. Quercus mongolica forests, however, were floristically dissimilar to the other forest types. Floristic distance of both forests and steppes were significantly correlated with ΔMAT and geographic distance, while there was a significant correlation with ΔMAP for forests only, but not for steppes. The floristic difference between forest understorey and steppe plots within each site showed no significant correlations with climatic or geographic factors.ConclusionsThe plant species distribution of both forest and steppe was more dependent on temperature than on precipitation gradients. The floristic distance between the forest understorey and steppe plots within sites seemed to depend on factors other than climate.

The availability of mineral nitrogen in Mediterranean open steppe dominated by Stipa tenacissima L.

The area of interest is located in the Sierra de los Filabres in semi-arid steppe of the province of Almeria in Spain. The amount of water in the soil is a limiting factor and its availability affects the structure and species composition of ecosystem. On the other hand, the type of vegetation affects the water loss via evapotranspiration and thus the soil microclimate. It has a great influence on the growth and activity of soil microbial communities and hence the dynamics of decomposition of organic matter and nutrient availability. The aim of this study was to assess the intensity of microbial transformations of soil organic nitrogen and describe changes in the content of nitrogen mineral forms at different depths in the semi-arid climate soil in the Mediterranean region. Availability and movement of nitrogen was monitored by capturing the mineral nitrogen into the structures of ion exchange resin applied to the soil in three different variants (control variant, a variant with the addition of cellulose, and the variant with the addition of raw silk). Ion exchange resins have been installed into soil profile in 2008, 2009, and 2010. After the in situ exposure the ion exchange resins were removed from the soil profile and the quantity of captured mineral N was determined by distillation titration method. The availability of ammonia-nitrogen was significantly affected by the addition of different substrates mainly by the additions of the raw silk, where the availability was regularly the highest. However, the availability of ammonia-nitrogen form was generally higher than the availability of nitrate form.