Koeleria Macrantha Research Articles

Acidophilous grasslands in the Locarnese region (Southern Switzerland): description and classification of main plant communities

This paper presents a phytosociological study of dry and mesophilous meadows and pastures in the Locarnese region (Insubria - Southern Switzerland). Seventy-one vegetation relevés were analysed using both hierarchical classification and nonmetric multidimensional scaling (NMDS) ordination. Seven main clusters were identified and described as follows: (i) xerophytic grasslands on sandy soil dominated by Koeleria macrantha; (ii) mesophilous meadows with Arrhenatherum elatius and Centaurea transalpina; (iii) semi-dry meadows with Chrysopogon gryllus; (iv) semi-dry grasslands with Carex fritschii and Thalictrum minus; (v) nutrient-poor Phyteuma betonicifolium-Festuca nigrescens montane zone grasslands; Nardus stricta grasslands dominated by (vi) Festuca paniculata or (vii) Carex pilulifera. From a phytosociological point of view, a new association named Phyteumo betonicifolii-Festucetum nigrescentis, classified into the Nardo strictae-Agrostion tenuis alliance was proposed. In addition, we confirmed the presence of the Holco-Chrysopogonetum grylli association, within the Bromion erecti, which up to now was provisional only.

Plant Community Transformations in Desert Rangeland Ecosystems – Evidence from the North-Western Caspian Lowland

Abstract—The article presents the results of long-term monitoring of successions, and the production dynamics in desert rangeland phytocoenoses over an 8-year period (2014–2021). It shows the current state of vegetative cover of the Chernozemelskaya sandy plain (north-west of the Caspian lowland, Republic of Kalmykia) following forest reclamation of fine-grained sands, carried out in the 1970s–1990s. The centers of soil deflation (aeolian erosion) differed by the degree of soil and vegetative cover transformation and the methods of the reclamation of open sands. Currently, a secondary vegetative cover has been formed on the previously identified deflation patches. The expansion and evolution of the current species composition suggests the development of secondary succession. The features of the synusial structure of desert phytocenoses reflect the state of plant communities. The relationship of the productivity of model pastures (shrub Callygonum aphyllum, subshrub Krascheninnikovia ceratoides, herbaceous species Stipa lessingiana, Artemisia lerchiana, Alyssum deserforum, Bromus tectorum, Carex stenophylla, Koeleria macrantha, Poa bulbosa) with precipitation in warm and cold periods of the growing season is analyzed. Under changing temporal and spatial climate dynamics, the successional processes are greatly influenced by wildfires and anthropogenic impact. It has been established that secondary successions under heavy transformation of the agro-pasture landscape develop more slowly. Thus, the natural and landscape environment of the current deflation centres in the rangelands of the North-Western Caspian region is an important factor determining the direction of succession.

Псаммофитная растительность долины реки Худан (Республика Бурятия)

Псаммофитная растительность долины реки Худан (Республика Бурятия)

Soil Infiltration Properties Are Affected by Typical Plant Communities in a Semi-Arid Desert Grassland in China

A process of infiltration from the soil surface to form soil water is known as soil infiltration; this is the only way for plants to absorb and use soil water. This process is closely related to nutrient migration, surface runoff, and soil erosion. The objectives of this study were to quantify the effect of typical plant communities on soil infiltration performance, reveal the interaction between soil infiltration rate and soil characteristics and plant roots, and determine the primary influencing elements on the Xilamuren grassland. The ring knife method was used to determine the soil infiltration rate at the 0–30 cm soil layer of six typical vegetation communities. The results indicated that the infiltration rate of the Koeleria macrantha community was highest at the soil depth of 0–5 cm, while that of the Convolvulus ammannii community was lowest, reaching 4.25 mm·min−1 and 0.53 mm·min−1, respectively. The soil infiltration rate of different plant communities gradually declined with the increment of soil depth. The strongest correlations were found between bulk density, total porosity, organic matter, root characteristics, and soil infiltration rate. The bulk density, initial water content, capillary porosity, and clay content were the primary influencing factors acting on soil infiltration in the region. Other factors indirectly impacted the infiltration rate by modifying bulk density, which was a crucial limiting factor determining the infiltration rate in the research region. The study’s findings will give theoretical and practical assistance for the prevention and management of soil deterioration and grassland restoration in this area.

Methods for using pastures in semi-desert zone of West Kazakhstan

The research allowed one to prove the seasonal organization of pasture economy using the distant pasture. The studies were carried out in 2018-2021 in the semi-desert zone of Western Kazakhstan. The aim of the research is to study and select the best ways to use pastures for organizing measures for their rational management. The soil of the areas of unsystematic and seasonal grazing is light chestnut medium loamy. Driving pastures are located in the sands zone. In the summer period, an increase in the number and occurrence of valuable pasture plants Kochia prostrata, Agropyron desertorum, Festuca valesiaca, Leymus ramosus, Koeleria cristata was noted on seasonal pastures. On the distant site of sandy pastures, 23 plant species of different economic and botanical groups have been determined, and due to the natural conditions of sands in the phytocenosis, the occurrence of valuable plants in the forage ratio is high. By the middle of summer, in the area of seasonal and distant pastures, despite the loss of forbs from the vegetation composition and drying of cereals, the yield of green phytomass was 0.81-1.03 t/ha, which is 0.43-0.65 t/ha. In this work, it was concluded that to improve the efficiency of pasture resource management, it is important to use seasonal pastures with the inclusion of a distant site in pasture rotation, which is the scientific novelty of the research.

The current state of pastures in Western Kazakhstan, depending on the method of their use

The process of pasture resources management in Western Kazakhstan is complicated by the deterioration of vegetation cover with the manifestation of degradation and desertification processes as a result of unsystematic grazing. The aim of the research is to study distant pasture grazing on the productivity of pastures for their rational use. Field experiments were carried out in 2018–2021 on the pastures of the semi-desert zone of the Western Kazakhstan region on the territories of the “Miras” peasant farm in the Bokeyurdinsky district. As experimental plots, 4 pastures were selected, used in different ways: unsystematic, seasonal and distant pastures. 3 pasture areas are located on the relief part of the semi-desert zone, and the distant-pasture area is located in the sandy part of Ryn-Peski. To study the influence of the methods of use on the productivity of pastures on the polygon areas, regular observations of the quantitative and qualitative parameters (projective cover, height, species composition, yield) of phytocenoses were carried out. The research allowed to prove the seasonal organization of pasture economy using the distant pasture. In the summer period, an increase in the number and occurrence of valuable pasture plants Kochia prostrata, Agropyron desertorum, Festuca valesiaca, Leymus ramosus, Koeleria cristata was noted on seasonal pastures. On the distant site of sandy pastures, 23 plant species of different economic and botanical groups have been determined, and due to the natural conditions of sands in the phytocenosis, the occurrence of valuable plants in the forage ratio was high. By the middle of summer, in the area of seasonal and distant pastures, despite the loss of forbs from the vegetation composition and drying of cereals, the yield of green phytomass was 8.09–10.25 c/ha, which is higher than in the area of unsystematic grazing by 4.28–6.44 c/ha. In this work, it was concluded that to improve the efficiency of pasture resource management, it is important to use seasonal pastures with the inclusion of a distant site in pasture rotation, which is the scientific novelty of the research.

ОСОБЕННОСТИ СЕЗОННОГО РАЗВИТИЯ ПАСТБИЩНЫХ УГОДИЙ ЯШАЛТИНСКОГО РАЙОНА КАЛМЫКИИ

The basis of the forage base of most regions of the Republic of Kalmykia is natural lands. The current state of natural pastures in the republic is due to the specifics of natural and climatic and anthropogenic factors. In our work, we consider the main types of steppe vegetation, which are used as natural pastures in the Republic of Kalmykia. Among them, drought-resistant, salt-tolerant and grazing-resistant perennial herbs and subshrubs, many annuals, ephemers and ephemeroids predominate. Formation of the productivity of forb-ephemeral vegetation, the representatives of which are: kermeks (Limonium platiphyllum, L. sareptanum), blueheads (Eringium planum, E. campestre), kahris (Cachrys odontalgica), ferulas (Ferula caspica, F. nuda), tulips (Tulipa biebersteiniana, T. biflora, T. gesnerii), bulbous bluegrass (Poa bulbosa) and others, begins in the second half of April, reaching a maximum of 5.9 ... 6.7 c/ha in May. The high productivity of pastures of the grass-wormwood plant community up to 9.8 c/ha is provided by Austrian wormwood (Artemisia austriaca), white wormwood (Artemisia lersheana), Welsh fescue (Festuca valesiaca), Lessing's feather grass (Stipa lessingiana), prutnyak (Kochia prostrata), yarrow tansy (Tanacetum achilleifolium), sage (Salvia desertorum, S. stepposa, S. aethiopis) and others. The productivity of the chamomile-fescue community in dry years ranges from 2.0 to 5.3 c/ha, in wet years - 5.4...11.2 c/ha and is characterized by a smooth course with a maximum falling on one of the summer periods. The dominant community is the compound chamomile (Pyrethrum millefolium), edificators are feather grass (Stipa capillata, S. ucrainica, S. lessingiana), fescue (Festuca valesiaca), thin-legged slender (Koeleria cristata) and others.

Threshold dose rates for the cytogenetic effects in crested hairgrass populations from the Semipalatinsk nuclear test site, Kazakhstan

An assessment of cytogenetic effects in crested hairgrass (Koeleria gracilis Pers.) populations was carried out within the Semipalatinsk nuclear test site (Kazakhstan) where combat radioactive substances were tested in 1953–1957. Current levels of radioactive contamination within this site are varied by orders of magnitude, while soil characteristics and heavy metal pollution are similar. The main contribution to the absorbed by plants doses at this site was caused by incorporated 90Sr. The frequency of cytogenetic alterations in crested hairgrass was investigated in a wide range of doses (10−4–13 Gy/growing season) at 100 sampling points. For the first time in the field conditions the shape of the cytogenetic effects - dose rate relationship was evaluated with acceptable accuracy and found to be nonlinear. The frequency of aberrant cells remained practically unchanged up to 49 µGy/h. Exceeding the threshold dose rate lead to a steep increase in the aberrant cells frequency from less than 2% up to 16%. The main contribution to the cytogenetic effects was made by double bridges and fragments. Breakpoints for other types of cytogenetic alterations were also evaluated (7 µGy/h for single fragments and bridges; 74 for double fragments and bridges; 81 for mitotic abnormalities).

Species Distribution in Cenofloras of the Cryophytic Steppes and Cushion Plants with the Participation of Stellaria pulvinata Grub. in the Mongolian Altai

The distribution of the vascular plants species occurring in the composition of high mountain communities with the participation of stitchwort polster (Stellaria pulvinata Grub.) are analyzed. They form a separate altitudinal belt in the altitudinal-zonation range of vegetation and belong to the arid class of zonality types in the central Mongolian Altai (2700–3300 m a.s.l. Baltic System (BS)). The analysis identified cenotically active species in the cenofloras of cryophytic steppes and cryophytes–forb cushion plants, which include distinctive elements of cryo-xerophytic conditions, such as Oxytropis oligantha, O. chionophylla, Saussurea leucophylla, Chamaerhodos altaica, Arenaria meyeri, and Androsace septentrionalis; montane species confined to the high mountain areas of southern Siberia and central Asia (Festuca kryloviana and Poa altaica) and bunchgrasses, which are represented by widely distributed species typical of the steppe (Festuca lenensis and Koeleria cristata). Modeling of the spatial distribution revealed that the ecological–cenotic optimum for the majority of species in the region is found outside of the cryophytic steppes and cushion-plant growth area. According to the identified potential distribution ranges of species accompanying Stellaria pulvinata, a close relationship has been established between the vegetation of the central Mongolian Altai high mountains and the mountains of southern Siberia.

Carici supinae–Betuletea pendulae — новый класс лесной растительности в степной зоне Западно-Сибирской равнины и Зауралья

Carici supinae–Betuletea pendulae — новый класс лесной растительности в степной зоне Западно-Сибирской равнины и Зауралья

Нелинейность зависимости частоты цитогенетических нарушений от содержания Sr-90 в растениях Тонконога тонкого с территории Семипалатинского испытательного полигона

To construct dose-response curves for basic biological indicators, such as mortality, fertility, ra-diation-related morbidity, genetic effects, data of experimental studies of acute radiation expo-sure carried out under controlled conditions within laboratory walls are mainly used. However, the results of experimental research cannot be applied to research of radiation effects on biological species inhabiting and growing in large territories, contaminated with the mixture of -, - and -emitting radionuclides with different penetrativeness, biological efficiency and mobility in the soil-plant system. Large scale study of impact of 90Sr in different concentrations in the Koeleria gra-cilis plants on the frequency of cytogenetic damage formation. For the study 105 experimental points on the «4A» landing in the Semipalatinsk test site were selected. The landing was earlier used for radioactive substances testing, the 90Sr concentration in plants varied between 102 and 108 Bq/kg. It was the first open-air study that allowed researchers to obtain the curve of the rela-tionship between the radioniuclide content in the plants and the frequency of cytogenetic altera-tions. The threshold for cytogenetic alterations induction in the plants below 1.58105 Bq/kg was found. At the higher 90Sr concentrations statistically significant increase (p<0.001) in the frequen-cy of cytogenetic alterations induction from <2% to 18% was observed. Among all cytogenetic disorders found in the plants double bridges and fragments occurred more frequently; it indicates that formed cytogenetic alterations were induced by radiation.

Structure and ecological features of the Yeravninsky steppes flora (Western Transbaikalia)

The paper is devoted to the characteristics of the floristic diversity of steppe vegetation in the southern part of the Vitim plateau in Yeravninskaya and Uldurginskaya basins. There is a southern border of the permafrost. The flora of the steppes is characterized by a depleted composition in comparison with the steppes of the Selenga middle mountains. Some widespread plant species of the true steppes of the Central Asia are absent here. The basis of the ecological and phytocoenotic structure is the steppe group, which is dominated by mountain and forest-steppe plant species. There is less participation of the true steppe species; this fact indicates an insular nature of these steppes. A group of light-coniferous species is significant; they are the part of the cryoarid forest-steppe complexes of the Vitim plateau. In the ecological structure of the flora xeromesophyte and gemixerophyte species dominate. They have the most important coenotic role in the formation of the vegetation cover of these steppes. The cereals species are of high coenotic significance, there are indicators of the dry bunchgrass steppes of Southern Siberia (Poa botryoides (Trin. ex Griseb.) Roshev., Agropyron cristatum (L.) Gaertn., Koeleria cristata (L.) Pers.). The role of mesoxerophytic of East Asian and Daurian-Manchurian species is also high (Filifolium sibiricum (L.) Kitam., Stellera chamaejasme L., Bupleurum scorzonerifolium Willd.). They are typical for meadow steppes of the Central Asian sector of the Palearctic.

Rhizosphere priming is tightly associated with root-driven aggregate turnover

The root-driven soil aggregate turnover dynamics and rhizosphere priming effect (RPE, changes in soil organic carbon (SOC) decomposition caused by living roots) are central to the understanding of SOC cycling. However, the association between aggregate turnover and the RPE has not been illuminated in plant-soil systems because of methodological difficulties. Using rare earth oxides to trace the transformations among different aggregates and 13C natural abundance labeling, we for the first time simultaneously investigated aggregate turnover and the RPE at two phenological stages of two grass species (Agropyron cristatum and Koeleria cristata): tillering (40 days after planting, DAP40) and jointing-heading (DAP63). We found that aggregate turnover rates varied widely, with a range between 0.006 day−1 and 0.024 day−1, i.e., turnover times (the reciprocal of turnover rates) ranged from 41 to 168 days, and were significantly influenced by plant species, sampling date and their interaction. Particularly, greater aggregate turnover rates (2% ~ 68%) and transformations in breakdown and formation pathways were found for K. cristata than for A. cristatum at DAP63. The RPEs increased with plant growth and ranged from −29% to +163%. Especially, the RPE and microbial biomass C were significantly greater for K. cristata than for A. cristatum at DAP63. Root-driven aggregate turnover was tightly associated with the RPE, possibly because of the release of aggregate-protected C for microbial decomposition. There was no net C loss mainly because increased aggregate formation could have sequestrated root-derived C in macroagrgegates and thus counteracted the C loss by the positive RPE. We therefore propose a new framework of root-driven aggregate turnover for considering how plant roots influence SOC dynamics via aggregate turnover. Root-accelerated aggregate turnover acts as a “key”: enhancing SOC decomposition (i.e. RPE), while simultaneously accelerating the occlusion of root-derived C and thus facilitating new C sequestration. This framework highlights that living root-driven aggregate turnover alters the physical protection of SOC and regulates the RPE, which aligns well with the emerging perspective of SOC stabilization.

СОСНОВЫЕ ЛЕСА КЛАССА ERICO-PINETEA HORVAT 1959 В ДАГЕСТАНЕ (СЕВЕРНЫЙ КАВКАЗ)

The paper represents the results of grass pine forests classification in Dagestan by the Brown-Blanquet method. A number of 68 releves of pine forests (taken from the paper by Abdurakhmanova et al., 2018) were included in two higher categories of vegetation – the boreal forests of the class Vaccinio–Piceetea Br.-Bl. in Br.-Bl. et al. 1939 and the sub-Mediterranean thermophilous forests of the class Erico–Pinetea Horvat 1959 based on the quantitative classification. Comparative syntaxonomic analysis of the Caucasian communities of the Erico–Pinetea class revealed their high level of floristic originality in comparison with similar forests of southern Europe, Western Asia and Crimea. This corresponds to the unique bioclimatic conditions of Dagestan located on the territory with a clear effect of «rain shadow» from the high mountain ranges of the Greater Caucasus stretching on the way of the western Atlantic moist air masses that result in the high climate continentality. These essential ecological and floristic peculiarities of the grass pine forests of the Eastern Caucasus provided a basis for the description of a new order — Alchemillo sericaceae–Pinetalia sylvestris ord. nova hoc loco representing the extreme eastern part of the Erico–Pinetea class range. The diagnostic species group of the order includes dominantly Eastern-Euxinian, Caucasian endemics and Eurasian xerophilous species: Juniperus oblonga, Alchemilla sericata, Galium valantioides, Peucedanum ruthenicum, Thalictrum foetidum, Rosa elasmacantha, Filipendula vulgaris, Koeleria cristata, as well as diagnostic species of subordinated alliances. The order includes two alliances demonstrating the ecological and floristic differences of Dagestan pine forests due to the thermic factor. The alliance Bupleuro polyphylli–Pinion sylvestris all. nova hoc loco (holotypus of the order) includes grass pine forests with predominance of thermophilous floristic elements. Differential species of the alliance are Astrantia major, Valeriana alliariifolia, Polygonatum verticillatum, Pyrethrum coccineum, Psephellus daghestanicus, Galium rubioides, Calamagrostis arundinacea, Rubus saxatilis, Brachypodium pinnatum, Fragaria vesca, Fragaria viridis, Primula macrocalyx, Anthriscus sylvestris, Amoria ambigua, Bupleurum polyphyllum, Hylocomium splendens, Pleurozium schreberi, Dicranum scoparium, Rhytidiadelphus triquetrus, Rhodobryum roseum, Climacium dendroides, Abietinella abietina, Plagiomnium cuspidatum, Betula litwinowii, B. pendula. Three associations and two non-rank communities were included in the alliance (Carici albae–Pinetum sylvestris Ermakov, Abdurakhmanova, Potapenko 2019 — holotypus of the alliance, Ranunculo caucasicae–Pinetum sylvestris ass. nova hoc loco, Viburno lanatae–Pinetum sylvestris Ermakov, Abdurakhmanova, Potapenko 2019, community Stachys atherocalyx–Pinus sylvestris, community Centaurea phrygia–Pinus sylvestris). The alliance Onobrichido cornutae–Pinion sylvestris all. nova hoc loco includes unique cryophilous pine forests with predominance of the cushion plants in the gound layer and numerous constant species of Caucasian cryophilous and xerophilous endemics. Diagnostic species of the alliance are Onobrychis cornuta, Festuca woronowii, Gypsophila tenuifolia, Salvia canescens, Rosa elasmacantha, Androsace koso-poljanskii, Galium brachyphyllum, Thymus daghestanicus, Asperula alpina, Anthemis dumetorum, Scutellaria oreophila, Satureja subdentata, Potentilla recta, Teucrium polium, Euphorbia virgate, Scabiosa gumbetica, Astragalus alexandri, A. fissuralis, Seseli alexeenkoi, Pseudomuscari pallens, Rhamnus pallasii, Vincetoxicum funebre, Jurinea ruprechtii, Helianthemum dagestanicum, Stipa caucasica, Centaurea edmondii, Selaginella helvetica, Scorzonera filifolia, Dracocephalum austriacum, Viola somchetica, Oxytropis lanata. At present the alliance is represented by a single association – the Onobrichido cornutae–Pinetum sylvestris ass. nova hoc loco. The results of the classification have demonstrated a significant level of originality of the Caucasian grass pine forests and a high floristic status of the Caucasus as a one of the important centers of modern phytodiversity.

Materials to the creation of the botanical preserve of local importance «Novozhanivskyi»

The results of ecological and floristic studies of the rarity component of the urban flora of Kharkiv City in the valley of the Udy River within the Novobovarskyi microdistrict are presented. Field studies were conducted in 2017‒2020. A triangular section of 30.48 hectares was investigated near the Novozhanovo railway station. It is located on the left bank of the river Udy and is bounded on both sides by railway embankments. The Udy River valley is situated in the northeast of the city, mainly in the previously underdeveloped areas; its significant part lays in the exclusion zone of the Kharkiv railway junction and road transport routes. A large area of the river valley is swampy, therefore unsuitable for economic use. The Udianskyi eco-corridor of local importance passes through the city. It consists of two key areas: the Zhovtnevyi Hydropark wetlands and the Kriukivskyi hydrological reserve of local importance. Currently, it has been proposed to create a botanical preserve of local importance "Novozhanivskyi" for the protection of species and associations rare for Kharkiv Region and for conservation of the true meadow formation (Prata genuine) of the class Festuceta pratensis. The site is of scientific importance, since a number of species growing there are listed in the Red Data Book of Ukraine and need protection under Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) – Ophioglossum vulgatum, Botrychium lunaria, Anacamptis coriophora, A. palustris, Epipactis palustris, Parnassia palustris, Centaurium erythraea, C. pulchellum, Valeriana officinalis, Inula helenium, Dianthus stenocalyx. The investigated area phytodiversity is represented by meadow and psammophytic species of vascular plants: Calamagrostis epigeios, Agrostis vinealis, Poa pratensis, Koeleria cristata, Nardus stricta, Sieglingia decumbens, Anthoxanthum odoratum, Festuca orientalis, Juncus gerardii, Botrychium lunaria, Genista tinctoria, Solidago virgaurea, Euphrasia pectinata, Stellaria graminea, Hieracium villosum, H. umbellatum, Polygala sibirica, Plantago lanceolata, Equisetum arvense, Achillea submillefolium. For the five plant species listed in the Red Data Book of Ukraine, the distribution maps within the area of proposed preserve are given.

Plant-Soil Feedbacks and Facilitation Influence the Demography of Herbaceous Alpine Species in Response to Woody Plant Range Expansion

Plant species migrations, or range shifts, in response to changing climate are one of many interacting factors influencing plant population and community dynamics in an era of global change. Range shifts may cause novel assemblages of competing species because species may respond to changing climate at different rates. Range-expanding species may directly influence resident species through resource competition or indirectly by modifying the local environment both aboveground and belowground. Further, range-expanding plant species can create novel plant-soil feedbacks (PSFs) by altering soil microbial community structure and function and the interactions of resident plant species with microbial symbionts. These changes can have important implications for resident plant population dynamics and their ability to coexist with novel competitors. Here we test the impacts of competitive interactions and plant-soil feedbacks (PSFs) of a range-expanding sagebrush species (Artemisia. rothrockii) on the demography and population growth rates of two resident alpine plant species (Koeleria macrantha and Eriogonum ovalifolium). We use an experimental, multi-year field approach combined with integral projection modeling to determine how PSFs and competition influence species coexistence in both the historic and range expansion zone of A. rothrockii. We find that sagebrush has an overall net negative effect on herbaceous plant demography, primarily due to negative PSFs for plants growing in sagebrush-conditioned soil. However, these negative soil effects are partially buffered via facilitation effects for herbs growing under or nearby sagebrush canopies. In general, population growth rates were more sensitive to survival than other demographic rates, furthermore this sensitivity to survival was higher for herbaceous species in sagebrush soils. Identifying the major drivers of plant population dynamics and species interactions remains an important and unresolved question in ecology. PSFs are a central mechanism influencing plant species interactions, yet the majority of PSF research has made little direct connection between plant population dynamics and PSFs in situ. We believe that utilizing a field-based approach, focusing on multiple components of plant demography, is an important next step in understanding the role of PSFs and species interactions in a rapidly changing world.

Plants with Horticultural and Ecological Attributes for Green Roofs in a Cool, Dry Climate

Green roofs are building surface treatments where plants are grown in medium on a rooftop to cool or insulate buildings and/or to ameliorate negative environmental impacts of buildings. We initiated a 2-year study to characterize medium and weather conditions on a rooftop in a cool-dry climate and to identify plant species with horticultural and ecological attributes that survive and thrive on an unirrigated semi-intensive green roof in a cool-dry climate. Eighty-eight cold-hardy, drought-tolerant species with horticultural or ecological attributes were identified and planted into 12.7-cm-deep medium in trays that were placed on a rooftop. Medium temperatures and moistures were recorded, and plant survival and vigor were quantified. Hourly medium temperatures varied from –22.3 to 43 °C. Monthly medium water moistures varied from –2.5 to –73.3 kPa from May to September, and from –7.6 to –195 kPa from October to April. Monthly air temperature, relative humidity and irradiance varied from –9.4 to 21.7 °C, 44% to 80%, and from 206 to 1222 μmol·m−2·s−1. Mean survival scores decreased (4 = 100% survival) from 2.6 with grasses, to 2.3 with succulents, to 1.8 with temperate perennials, to 0 for geophytes (all died). Among grasses, Festuca ovina VNS, Koeleria macrantha 07-901 ND, Panicum virgatum, and Sporobolus heterolepis performed well. Among succulents, Sedum acre, S. album ‘Coral Carpet’, S. cauticola ‘Sunset Cloud’, S. ‘Czar’s Gold’, S. ellecombianum, S. hybridum ‘Immergruchen’, S. requieni, S. sexangulare, S. spurium ‘Dragon’s Blood’, ‘John Creech’, ‘Pearly Pink’, ‘Ruby Mantle’, and ‘Tricolor’ performed well. Among temperature nonsucculent perennials, Allium ceranum and senescens ‘Glaucum’, Geum triflorum, Talinum calycinum, and Thymus praecox ‘Red Creeping’ performed well. Data on Sedum suggested that medium-low temperature was more limiting to survival than moisture level. The differences in species that performed well here, compared with other studies, underscores the importance of regionally specific green roof plant species studies.

Effect of substrate depth on plant community development on a Michigan green roof

Green roofs are gradually being accepted and implemented across North America as they can mitigate many of the negative effects that urban areas have on humans and the environment. As rooftops are filled with living plants, individual species need to be tested for longevity and suitability. Twenty-two plant species including herbaceous perennials, grasses, and sedum were evaluated on a green roof at substrate depths of 4.5, 10, and 20 cm over an eight-year period in East Lansing, Michigan. Plants were irrigated when needed during the first two years, but had to rely on natural rainfall thereafter. All five species of sedum were still present at the end of the eight-year period, but only seven of the 17 herbaceous perennials and grasses survived. Of the herbaceous perennials and grasses, Allium cernuum was by far the dominant species in both the 10 and 20 cm deep zones. Sporobolus heterolepis and Koeleria macrantha also established themselves in the 20 cm zone, but all other species were either only present in trace amounts or had completely disappeared. Substrate moisture was probably the major factor in terms of species survival and a drought during 2016 was likely the cause for the large loss of species. Deeper substrates supported a larger variety of species, but plant species diversity decreased over time at all substrate depths. This study emphasizes the fact that if herbaceous perennials and grasses are to be successful on green roofs, then irrigation may be critical to mitigate drought and maintain species diversity. It also points out the importance of long-term studies to accurately evaluate green roof plant communities and provides the framework for a continuation of the same study in other areas of the world.

Chromosome Numbers and Male Meiotic Course Analysis in Some Wild Grasses of Tribe Aveneae from Uttarkashi District Hills, Uttarakhand, India

Present study on male meiotic analysis of wild grass species from Uttarkashi district hills, Uttarakhand, India provides chromosome numbers for 10 species belonging to tribe Aveneae, family Poaceae. The study reports chromosome numbers firstly for Helictotrichon uniyalii (2n=4x=28, Rarhi Valley), Trisetum aeneum (2n=2x=14, Assi Ganga Valley) and Tr. clarkei (2n=4x=28, Assi Ganga Valley), and confirmed in the Indian species, Avena fatua (2n=6x=42, Purola Valley), Koeleria macrantha (2n=2x=14, Bhagirathi Valley), Phleum alpinum (2n=4x=28, Har Ki Dun Valley), P. pratense (2n=4x=28, Assi Ganga Valley), Trisetopsis aspera (2n=6x=42,; Assi Ganga Valley), T. virescens (2n=4x=28, Assi Ganga Valley and Bhagirathi Valley) and Tr. spicatum (2n=4x=28, Assi Ganga Valley, Bhagirathi Valley, and Har Ki Dun Valley). The meiotic course was normal in most of the species, although suggested a paracentric inversion in a plant of Tr. spicatum.

Impact of instream sand mining on habitat destruction or transformation using coupling models of HSI and MLR

Several human activities like sand mining, dam construction have intensive effect on river ecosystem. Instream sand mining is one of them to hindrance on riverine biota. Hence, an attempt is made in this study to assess three tier habitat degradation or alteration caused by instream sand mining from channel bed to riparian and bank site in upper, middle and lower segments of Kangsabati River. Habitat Suitability Index (HSI) is applied to detect geo referenced ecological information on two different condition i.e. habitat suitability of two dominating species of Koeleria macrantha and Cynodon dactylon (pre mining) and degraded or altered habitat incorporated with mining responses (post mining). HSI prepared five different suitable class taken seven dominating variables i.e. river channel, sandchar, riparian zone, slope, elevation, dry and moist sand layer using multiple logistic regressions (MLR) under GIS platform. MLR denotes sandchar deposition, elevation as significant variables of Koeleriamacrantha dominance along the bank while moist sand layer, riparian zone signified on Cynodondactylon dominance across the riparian site. HSI indicates low-suitable class of Koeleriamacrantha and Cynodondactylon dominated in largest sand mining area as lower (82%, 86%), middle (58%, 89%) and upper segment (77%, 78%) whereas largest mining area under two dominant species reaches low-suitable class as lower (79%, 58%), middle (89%, 82%) and upper segment (92%, 70%) respectively. In spite of variables influence on species dominance, massive sand mining leads to destroy the habitat suitability. Therefore, in situ habitat suitability of dominant species either degraded or altered throughout the channel.