Peculiarities herb-bunchgrass steppes of Western Predcaucasia

Relevance. The article presents the materials of the geobotanical examination of the virgin steppes of the Western Predcaucasia. The relevance of the study is due to the modern state of natural grass stand, which is under constant anthropogenic influence.Methods. The research points are located in the southwestern part of the Stavropol Territory and the northeastern part of Karachay-Cherkessia, within the absolute heights of 500–880 m. The description of vegetation and its analysis was carried out on ten accounting sites (10x10 m) according to methods generally accepted in geobotany.Results. It was revealed that in the grass stand the grass familyhas on average 17,5% (its weight fraction is 70–80%). In the formation of grass stand plant associations, the leading role belongs to the dominant sod steppe-grasses: Stipa pulcherrima, Festuca valesiaca, Festuca rupicola, Bothriochloa ischaemum, etc. Legumes (Medicago romanica, Trifolium pratense, Onobrychis arenaria) are the main source of protein for animals, they are diverse and have on average 10,8%, but in weight terms they are inferior to sod steppe-grasses. The flora of the studied steppes is represented by a number of economically valuable plants. These are sod steppe-grasses — the creators of the main feed mass of the steppe. They are also sources of a protein component for animals. But the main source of protein in the steppe grass stands are representatives of the legume family (species Trifolium, Medicago, Onobrychis, etc.). Nectariferous plants (Filipendula vulgaris, Galium ruthenicum, Echium russicum) and drug plants (Adonis vernalis, Glycyrrhiza glabra, Thymus marschallianus, etc.) are found in the steppe. The spectrum of life cycles of the flora is noteworthy. There is a high percentage of perennials — from 66,7 to 97,8%. This fact indicates that the axes of ecological niches are packed relatively tightly by perennials — persistent competitors of annual plants (more often weeds). Until mid-summer the generative stage of development of wild plant species reaches on average 80%. Their gene pool can be recommended for the restoration of low-productive steppe grass stand, as well as for use in selection work.

Nilai VFA dan NH3 Rumput Alam Padang Penggembalaan Kecamatan Haharu Kabupaten Sumba Timur

This study aims to determine the value of volatile fatty acids (VFA) and ammonia (NH3) of natural grass in grazing fields in vitro. The study used a direct survey method in the field. Natural grass was tested in vitro using Bali cattle rumen fluid. The data obtained were analyzed using descriptive analysis based on the mean and standard deviation. Natural grass consisted of Heteropogon insignis, Bracharia decumbens, Bothriochloa ischaemum. The measurement of the value of VFA uses steam distillation, while the method of measuring the value of NH3 uses Conway micro diffusion. The results showed that Bracharia decumbens grass had a total VFA value of 74.48 mM and an NH3 value of 8.50 mM which was higher than Heteropogon insignis grass (total VFA 65.79 mM and NH3 6.67 mM), and Bothriochloa ischaemum grass (total VFA 60.64 mM and NH3 5.34 mM). The conclusion of this study was based on the value of VFA and NH3, Bracharia decumbens grass was a natural grass that may be cultivated for ruminants.

Soil Water Availability Changes in Amount and Timing Favor the Growth and Competitiveness of Grass Than a Co-dominant Legume in Their Mixtures

The grasslands on the semi-arid Loess Plateau of China are expected to be particularly responsive to the size and frequency changes of extreme precipitation events because their ecological processes are largely driven by distinct soil moisture pulses. However, the plant growth and competitiveness of co-dominant species in response to the changes in the amount and timing of soil water are still unclear. Thus, two co-dominant species, Bothriochloa ischaemum and Lespedeza davurica, were grown in seven mixture ratios under three watering regimes [80 ± 5% pot soil capacity (FC) (high watering), 60 ± 5% FC (moderate watering), and 40 ± 5% FC (low watering)] in a pot experiment. The soil water contents were rapidly improved from low to moderate water and from moderate to high water, respectively, at the heading, flowering, and maturity stages of B. ischaemum, and were maintained until the end of the growing season of each species. The biomass production of both species increased significantly with the increased soil water contents, particularly at the heading and flowering periods, with a more pronounced increase in B. ischaemum in the mixtures. The root/shoot ratio of both species was decreased when the soil water availability increased at the heading or flowering periods. The total biomass production, water use efficiency (WUE), and relative yield total (RYT) increased gradually with the increase of B. ischaemum in the mixtures. The relative competition intensity was below zero in B. ischaemum, and above zero in L. davurica. The competitive balance index calculated for B. ischaemum was increased with the increase of the soil water contents. Bothriochloa ischaemum responded more positively to the periodical increase in soil water availability than L. davurica, indicating that the abundance of B. ischaemum could increase in relatively wet seasons or plenty-rainfall periods. In addition, the mixture ratio of 10:2 (B. ischaemum to L. davurica) was the most compatible combination for the improved biomass production, WUE, and RYTs across all soil water treatments.

Long term changes of the inner-alpine steppe vegetation: the dry grassland communities of the Vinschgau (South Tyrol, Italy) 40–50 years after the first vegetation mapping

Aims: The Vinschgau is the driest inner-alpine valley in the Eastern Alps and harbours a unique steppe vegetation. We studied these dry grassland communities and aimed to answer the following questions: Which plant communities can be found currently? Do the syntaxa described by Braun-Blanquet in the 1960s still prevail in the area? Has there been any change in species composition over the last 40–50 years? Study area: Along an approximately 40 km transect, the south-facing slopes of the Vinschgau valley (South Tyrol, Italy) from Mals to Plaus were investigated. Methods: For the classification, 92 relevés were sampled in 2019 and compared with 76 relevés from the 1960s and ´70s by means of vegetation tables and ordinations (Detrended Correspondence Analysis). Results: Based on our investigation, the majority of dry grassland communities can be classified as Festuco-Caricetum supinae. Three subassociations were defined by the dominant species Stipa capillata, Bothriochloa ischaemum and Stipa pennataagg. The comparison of new and old relevés shows an increase in species from the class Sedo-Scleranthetea (e.g. Trifolium arvense, Erodium cicutarium) and the association Artemisieto-Agropyretum. In addition, ruderal elements (e.g. Erigeron annuus, Convolvulus arvensis) have also migrated into dry grasslands. A shift in the dominance over time can be recognized as well. In particular, Festuca rupicola and to some extent also Stipa capillata, have increased in abundance and frequency. Conclusions: We suggest to include the investigated closed dry grasslands in the alliance Festucion valesiacae. The rank of the character species at association, alliance and order level should be re-analysed. In order to obtain a better syntaxonomic overview of western and eastern alpine dry grassland communities in relation to Eastern European dry grasslands, a comprehensive study is absolutely necessary. Furthermore, long-term vegetation dynamics and vegetation change need to be studied in more detailed future studies. Taxonomic reference: Fischer et al. (2008). Syntaxonomic references: Mucina et al. (2016) for syntaxa from alliance to class level; Braun-Blanquet (1961) for associations. Abbreviations: agg. = aggregate; cf. = confer (means ‘compare’); DCA = Detrended Correspondence Analysis; s. lat. = sensu lato; s. str. = sensu stricto

Seasonal diet composition of Himalayan goral (Naemorhedus goral) in Kajinag National Park, Jammu and Kashmir, India

In temperate environments, forage availability and quality are known to influence life history traits of wild ungulates. However, variations in foraging strategies of these mountain dwellers with changing plant availability have received little attention. The seasonal vegetation availability in temperate climatic conditions of Kajinag National Park (KNP) was assessed by plot method at different altitudes (1900–3600 m a.s.l.) from 2018 to 2020 on seasonal basis. The objective of this study was to determine the impact of availability of vegetation on seasonal diet composition of Himalayan goral (Naemorhedus goral) inhabiting the National Park. We recorded 61 plant species whose availability differed significantly across seasons (F 3,240 = 20.14, p < 0.05). We found seasonal variation in the diet composition of Himalayan goral depicting a strong relationship between plant consumption and dynamic availability in the study area. Himalayan goral consumed herbs in spring (dominated by Dioscorea deltoidea relative importance value (RIV) = 27.20, Poa pratensis RIV = 14.99 and Themeda spp. RIV = 12.87), grasses in summer (dominated by Themeda spp. RIV = 34.12, P. pratensis RIV = 30.14, Bothriochloa ischaemum RIV = 22.72) and autumn (dominated by Themeda spp. RIV = 34.64, P. pratensis RIV = 30.14, Stipa spp. RIV = 29.73) and shrubs in winter (dominated by Indigofera heterantha RIV = 47.05, Prunus tomentosa RIV = 17.51 and Lonicera spp. RIV = 16.98). The annual diet of Himalayan goral was dominated by graze species (72.66%). The proportion of graze items in the diet showed a sharp decline from spring (90.67%) to winter (19.23%) whereas that of browse showed a huge increment from spring (4.67%) to winter (74.43%). This shift shows a survival or foraging strategy of a temperate ungulate in harsh winters with limited forage availability.

Bacterial Community Characteristics and Enzyme Activities in Bothriochloa ischaemum Litter Over Progressive Phytoremediation Years in a Copper Tailings Dam

Litter decomposition is the key link between material circulation and energy flow in ecosystems, resulting from the activity of resident microbes and various enzymes. This study investigated enzyme activity in litter and associated microbial community characteristics to help clarify the internal mechanisms associated with litter decomposition, while also providing researchers a scientific basis for soil remediation in mining areas. Results confirmed that the nutrient content of Bothriochloa ischaemum litter significantly increased as phytoremediation years progressed, while enzyme activities in litter varied over different phytoremediation years. During the litter decomposition process, cellulase predominated in the early phytoremediation stage and catalase predominated in the intermediate phytoremediation stage. Obvious differences were found in bacterial community structure and diversity over progressive phytoremediation years. Predominant bacterial genera mainly included Massilia, Sphingomonas, Curtobacterium, Amnibacterium, and Methylobacterium. Moreover, Methylorosula and Jatrophihabitans had relatively higher betweenness centrality, and played important roles in bacterial community positive interactions. Additionally, total nitrogen (TN) and total zinc in soil, sucrase and catalase activity in litter were the main environmental factors that affected the structural framework of bacteria in B. ischaemum litter. However, TN had the greatest overall effect on the structural framework of bacteria in litter. Results from this study can help our understanding of the role that litter plays in degraded ecosystems. Our results also provide a scientific basis for improving poor quality soil in areas affected by copper tailings while also amending ecological restoration efficiency.

Invasibility and Recoverability of a Native Plant Community Following Invasion Depend on its Successional Stages

Background: Exotic species invasions represent important causes of biodiversity loss in ecosystems. Yet, knowledge remains limited on the invasion advantage of exotic species (invasibility of native plants) and the ability of native species to recover following invasions at different stages of succession.Results: We selected three grasses (Setaria viridis, Artemisia gmelinii, and Bothriochloa ischaemum) representing early, middle, and late successional species, respectively, and an exotic species (Panicum virgatum) from a stable grassland community. Four types of field soil were collected to treat the three early, middle, and later successional species, plus the exotic species. We examined the invasion ability of the exotic species on native communities and the recoverability of these communities following invasion across succession. We compared the performance of the four plant species grown in their “own” and “other” soils in a 2-year glasshouse experiment. Here we show that exotic species performed better in soils of early and mid-successional species, owing to higher soil nutrients and microbial residues, than in the soil of later successional species. In the soil of exotic species, early and mid-successional species exhibited poor growth, while that of later successional species was unchanged.Conclusions: Our study demonstrated that soil nutrients and microbial residues create a soil legacy regulating the invasibility and recoverability (or resilience) of native plant communities and how it changed with vegetation succession.