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Among the shrub communities of the highlands of the Ukrainian Carpathians, there are rare ones that are on the verge of extinction in the modern conditions of anthropopression and climate change. These are the primary creeping shrub communities of the class Loiseleurio procumbentis -Vaccinietea Eggler ex Schubert 1960. They are considered as relicts and require monitoring and special attention in order to preserve them. Such vegetation centers include communities of the association Empetro-Vaccinietum gaultherioides Br.-Br. In Br.-Br. et Jenny 1926 corr. Grabherr 1993, which were discovered in the Borzhava massif in the last few years. The article provides information on the modern distribution of this communities in the Ukrainian Carpathians in general, and on the Borzhav massif in particular, its species composition and structure, as well as the prospects for its preservation. It was found that since the middle of the last century, the area of the communities Empetro-Vaccinietum gaultherioides association has halved at least, and some species of vascular plants characteristic only for the highlands are no longer recorded here. Climate changes manifested in the aridization of the air and disruption of the temporal and territorial distribution of the precipitation in the highlands, as well as the increased anthropogenic load due to uncontrolled tourism in the Borzhav massif, create threatening conditions for the development of Empetrum nigrum, which is on the verge of extinction here. The creation of the «Polonina Borzhava» Regional Landscape Park, which has been proposed by the authors for several years in a row, is urgent. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the seasonal floristic composition of grasses, forbs, and shrubs in a kermes oak (Quercus coccifera L.) shrubland in Chalkidiki, Greece, to estimate their nutritive value and to relate it to the nutritional requirements of small ruminants. All the herbaceous and woody species that were present in the study area were identified and collected at the beginning of each season. The samples were categorized into grasses, forbs, and shrubs. Dry matter (DM), ash, ether extract (EE), neutral detergent fiber assayed with heat stable amylase (aNDF), crude protein (CP), in vitro dry matter digestibility (IVDMD), calcium (Ca), and phosphorus (P) contents were determined. Forty-three plant taxa were identified (30 forbs, 7 grasses, and 6 shrubs). Forbs had higher mean values of ash (94.7 g/kg DM), CP (120.9 g/kg DM), Ca (16.9 g/kg DM), P (1.2 g/kg DM), and IVDMD (590.5 g/kg DM) compared to grasses (72.5 g/kg DM, 86.5 g/kg DM, 3.9 g/kg DM, 0.9 kg-1 DM, and 517.8 g/kg DM), and shrubs (44.5 g/kg DM, 79.9 g/kg DM, 11.0 g/kg DM, 0.7 g/kg DM, and 494.7 g/kg DM), respectively. Cool-season grasses can offer sufficient nutrients to grazing animals during autumn and winter, while shrubs support them during spring and winter. • 43 plant taxa were identified in a grazed by goats kermes oak shrubland in Greece. • Shrubs support the nutrition of grazing goats during spring and winter. • Cool-season grasses offer enough nutrients to grazing goats in autumn and winter. • Forbs have higher in vitro dry matter digestibility than grasses and shrubs. [ABSTRACT FROM AUTHOR]

The aim of this article is to identify both the diversity of plant associations in the extensive grasslands of the Geneva city parks as well as the different factors potentially influencing their composition and to propose suitable management measures. Methods: The vegetation was characterised according to the sigmatist phytosociological method. The data were then entered and standardised with the VEGEDAZ software, then attached to a reference unit according to the identification key of the Geneva syntaxonomic reference system. The settlement types and practices were identified and coded, then analysed with the R studio software. Results and discussion: Forty-three readings were carried out and sixteen associations identified. The most common association is Salvio-Mesobrometum. This demonstrates the resilience of urban parks to recover a diverse oligotrophic flora despite past intensive management. At the same time, the extensive grasslands of the Arrhenatherion (Lolio-Arrhenatheretum, Ranunculo-Arrhenatheretum and Tanaceto-Arrhenatheretum) are mostly the result of transformation linked to practices, for which the use of scythes and the removal of hay, seems to favour the number of species present. Finally, the ruderal environments constitute refuges for several heritage species. [ABSTRACT FROM AUTHOR]

Questions: Disturbances change the fundamental properties of grasslands on different spatio‐temporal scales. Uruguay is part of the Río de la Plata grasslands, and 60% is occupied by native grasslands dominated by perennial species. In plant communities dominated by tall tussock grasses, patchy and asynchronous field burns are a traditional practice among ranchers. We asked: how do the structural characteristics of vegetation vary in patches with different time since the last fire? Location: Grassland of the Eastern Hills, Uruguay. Methods: We selected 18 grazed sites in order to obtain a spatial chronosequence with four age categories since the last fire: 6, 18, 30, and more than 60 months before sampling. Plant composition, species richness, coverage of each species, bare soil, and standing dead biomass were determined in plots of 25 m2. We used non‐metric multidimensional scaling (NMDS) and the multiresponse permutation procedure (MRPP) to determine differences in community composition, and the ANOVA or the Kruskal–Wallis test to compare structural variables between patches of different burning ages. Results: Patches of different burning age had different species compositions. Species richness, Shannon diversity index, evenness, and bare soil decreased, whereas plant coverage, standing dead biomass, and vegetation strata increased as time since the last fire increased. Conclusions: Our study confirmed occasional and localized field‐burns as major driver of vegetation change and structural diversity in a grazed native grassland dominated by a tall tussock grass. On a larger scale, we observed the coexistence of patches in different successional stages and differences in species composition between patches belonging to early stages. These grasslands require asynchronous burning of patches to generate structural changes that maximize both the spatial and temporal heterogeneity. [ABSTRACT FROM AUTHOR]

This paper concerns itself with the study of sand beaches of the Boujagh National Park with an area of 3477 ha. The purposes of this study include the determination of the plant species diversity and plant groups. In ad-dition, the determination of the impact of environmental and specific variables on the presence or absence of certain species and their communities is another aim that the study follows. In order to attain those purposes, 52 plots across 6 transects of the district were used. In each plot, the materials were identified and abundance-dominance of species by using Braun-Blanquet criteria were obtained and their life forms were determined according to Raunkiaer clas-sification. To determine the plant groups, a Two-way analysis of significant modified species (Modified TWINSP-AN) was utilized. Detrended Canonical Analysis (DCA) was used to determine factors affecting plant groups. The results showed that four plant groups exist in this district: Convolvulus persicus-Crepis foetida subsp. Foetida grou-p, Argusia sibirica group, Eryngium caucasicum-Juncus acutus group and Rubus sanctus group. The first and seco-nd groups consist of higher percentages of therophytes and spread in areas where the soil contains more sand. Plants in the third and fourth groups spread in areas with stabilized sand and high percentage of silt. DCA analysis results showed that soil factors (texture, OC, Na, K, N, Ca, Mg) have significant relation with plant groups were studied. Among the plant groups, the percentage of silt and sand, species richness and life forms of therophytes and geop-hytes show significant relations. Therefore it can be concluded that these factors affect on the separation and distri-bution of plant groups.

Boujagh National Park, with water ecosystems including Boujagh and Kiashahr wetlands, has an area of approximately 3477.3 hectares. In order to study factors affecting the vegetation in aquatic and wet habitats, 44 releves were implemented in the region. To test the chemical properties of the available water, samples were collected from 22 releves. The results of a two-way species indicator analysis of the modified TWINSPAN suggested that four groups of plants were present in the region. The first group being floating, immersed and submerged and the third and fourth groups being mostly helophytic. The second group of plants grows in areas with sand and mud. The results of comparative DCA analysis of water factors (PH, Depth, P, N, Cl, CO3, Hco3, EC, Na, K) showed a significant correlation between the factors and plant groups and the most important factors influencing the distribution and separation of plants was found to be water depth. In addition, Boujagh and Kiashahr wetlands vegetation map, based on the plant groups, was also prepared.

The apparent monotony of the sparse steppe vegetation in the area of Ouled Dabbeb in southern Tunisia conceals a wide variety of flora and physiognomy. Based on several fieldcampaigns observations, the statistical analysis of collected data and a detailed phytoecological mapping, this work aims to highlight the influence of microtopography and topoclimates on the distribution of plant communities and on their diversity in the study-area. Indeed, most of the slopes of the pediments strips exposed to the South and South-East are marked by the presence of arid species e.g. Anthyllis sericea, Calligonum comosum, while the slopes facing North and North-East are marked by the presence of dry species e.g. Hammada scoparia, Hammada schmittiana. Therefore, a set of adjustments between climate and soil conditions at local level is at the origin of this fine mosaic of vegetal cover in the Ouled Dabbeb steppe region, where various plant species are coming into contact. [ABSTRACT FROM AUTHOR]

The relationships between species richness and driving factors might vary with taxa and spatial scale. For this study we used plant species data of eight groups from nature reserves in China, namely pteridophytes, gymnosperms, angiosperms, vascular plants, Chinese endemic species, rare and endangered plants, woody plants, and herbaceous plants, and eight putative environmental predictors to explore the relationships between plant species richness and environmental factors at two spatial scales (temperate region and national scale). Our data suggested that area, mean annual temperature, and mean annual precipitation were the determinants of variation in species richness within these eight groups in the temperate nature reserves of Shandong Province in China. The relationships between plant species richness and environmental factors were consistent in different groups. However, the relationships between species richness and mean annual temperature varied with spatial scale. In the temperate region, species richness was negatively correlated with mean annual temperature and positively correlated with mean annual precipitation, whereas on a national scale species richness was positively correlated with both mean annual temperature and mean annual precipitation. Our study confirmed that the relationships between plant species richness and environmental factors in nature reserves were consistent in the studied groups and varied with spatial scale. [ABSTRACT FROM AUTHOR]

The micromosaic structure of plant communities in dark conifer forests of dwarf shrub-true moss, boreal small herb-true moss, tall fern, and boreal tall herb subsections was studied in the Pechora-Ilych reserve. A typological scheme of microsites was constructed and the alpha-diversity of plants was assessed in microsites of different types; dominant and high-constancy species were identified. The proportions of area occupied by different microsites in test plots were calculated, and amounts of aboveground and belowground phytomass were estimated for every vascular plant species, dominant moss species, and the moss synusia as a whole in microsites of each type. [ABSTRACT FROM AUTHOR]

Nitrogen (N) enrichment has been pinpointed as a main driver for biodiversity change. Most of our knowledge of effects of increased N availability on ecosystems comes from northern Europe and America. Most other ecosystem types have been neglected. In contribution to filling this gap, our study examined the short-term effects of N enrichment in a N-manipulation (doses and forms) field study of a severely nutrient-limited Mediterranean ecosystem located in a Natura 2000 site in Portugal. Our aims were to (a) understand the effects of N enrichment on plant diversity, and to (b) link N-driven plant community changes with changes in soil inorganic N availability. In general, the standing plant community responded to short-term N enrichment with increased richness and evenness. Changes in the plant community occurred through changes in species composition and cover, and were correlated with soil N, and N and phosphorus availability. Fertilization with 80 kg NHNO ha y was the treatment which changed plant composition the most, while geophytes, hemicryptophytes and therophytes were the biological types more responsive to N enrichment. Dittrichia viscosa was the only species that responded significantly to increased N, i.e., its cover decreased in control plots, but increased in fertilized plots, suggesting that it could be used as an indicator of N enrichment in Mediterranean maquis. Changes in plant richness and evenness were correlated with the mean and/or the variation (standard deviation) of soil inorganic N parameters (e.g. nitrate concentration in the soil solution and the soil's ratio of bioavailable N and phosphorus) measured along the time between the two plant community assessments. However, short- and long-term effects can be quite distinct, thus highlighting the need for further studies. [ABSTRACT FROM AUTHOR]

For four consecutive years, following the fires in November 1993, temporal variations in species richness, cover and biomass of component plant groups in early post-fire chaparral succession were monitored on different aspects at the Stunt Ranch Santa Monica Mountains Reserve, southern California. Plant groups were categorized based on growth form, life form, ability to fix nitrogen, geographic origin and regeneration strategies. North-facing slopes exhibited higher species richness, higher species turnover rate over time and faster vegetation recovery in terms of biomass accumulation and return to pre-fire species composition. This was probably due to higher species richness and biomass of nitrogen-fixing species found on north-facing slopes in comparison to south-facing slopes. On both north- and south-facing slopes, annuals had the highest species turnover rate, followed by herbaceous perennials and shrubs. In the first four post-fire years, annual species were the largest floristic group, but herbaceous perennials and shrubs were the major contributors to community biomass. Nitrogen-fixing species and exotics contributed significantly to early post-fire community structure. Although the general trends in post-fire succession are clear in terms of temporal changes in the relative proportions of different plant groups, environmental variation and the nature of plant life histories of component species, especially dominant species, could alter such trends significantly. [ABSTRACT FROM AUTHOR]

Soil to plant transfer factor (TF) of radionuclides is an important input parameter in dose assessment models. The wide range of TF for each radionuclide reported in the literature for a particular plant type indicates that radionuclide concentration in soil is not the only factor influencing its uptake by the plant. Different soil properties and agricultural practices may influence the TF and these are also a function of the climate. Considering the wide variation in TF data, here we attempt to review the available literature on TF of radionuclides in tropical countries of the Indian subcontinent (India, Bangladesh, and Sri Lanka). TF under equilibrium conditions are not available for all radionuclides, in such cases TF of naturally existing stable analogs elements were compiled. With an emphasis on, transfer of radionuclides from soil to the edible compartment of the plant; the TF data for 21 elements are compiled for 12 plant groups classified as per IAEA, Technical Reports Series No. 472. The article also presents the analysis and discussion of the extent and limitations of the compiled data. The compiled TF may be useful in assessing the food chain transfer of radionuclides when site-specific information is not available. • Transfer factor (TF) data were compiled for Tropical region of Indian Subcontinent. • TF data were grouped based on element-plant group-edible compartment-soil types. • Wide variation was observed within and in between plant groups for same element. • Limitations of available TF data set also addressed in the review. [ABSTRACT FROM AUTHOR]

Studies focused on field measurements have been conducted to investigate how leaf wax n -alkane δ13C values vary among photosynthetic pathways (C 3 vs. C 4) or plant types (dicots, monocots, gymnosperms, magnoliids), and how n -alkane δ13C values respond to climate factors (precipitation, temperature). However, a systematic global analysis of plant n -alkane δ13C values with respect to major plant groups is still lacking, and the corresponding mechanism remains unknown. In this study, we compiled globally published n -alkanes δ13C data in modern plants. We find significantly negative correlations between δ13C wt values and mean annual precipitation (MAP) for C 3 plants (R2 = 0.30; p <.05), dicots (R2 = 0.28; p <.05) and magnoliids (R2 = 0.55; p <.05), but non-significant correlation between δ13C wt values and MAP for C 4 plants (R2 = 0.08; p =.12) or monocots (R2 = 0.01; p =.89). However, there are significantly positive correlations between δ13C wt values and mean annual temperature (MAT) in C 4 plants (R2 = 0.33; p <.05) and monocots (R2 = 0.35; p <.05), instead of weak correlations in C 3 plants (R2 = 0.09; p <.05), dicots (R2 = 0.03; p <.05) and gymnosperms (R2 = 0.06; p =.06). These results indicate that n -alkane δ13C values in C 3 dicots have more potential for paleoprecipitation reconstruction, while those in C 4 monocots are more likely to indicate paleotemperature changes. Our study supports use of leaf wax n -alkane δ13C values to gain information about paleoprecipitation and paleotemperature, but only in an appropriate paleoecological context [ABSTRACT FROM AUTHOR]