The semi-natural grasslands in Romanian mountains are particularly important for the sustainable development of this region. Therefore, the objective of this paper was to evaluate the effects of mineral and manure fertilization upon the sward in order to recommend certain versions which have minor repercussions upon the plant diversity. In this study, we examined the influence of organic and mineral fertilizers on the production, biodiversity and quality of green fodder. The experiment was set up in mountain grassland of Festuca rubra L. and Agrostis capillaris L., during five years. In the experiment was evaluated the effects of management treatments on productivity, biodiversity and quality of the forage grass. The rate applications of fertilizers determine the number of species and the rate of production. The small quantities of organic and mineral nutrients (10 t·ha-1 manure and 30 kg·ha-1 nitrogen) can lead to larger yields while at the same time, improving biodiversity conservation and the quality of forage. Using a low input-based management system can be a solution that will lead to higher yields and contribute to biodiversity conservation and the good quality of the forage. In conclusion the use of a fertilizer management regime based on small quantities of organic and mineral nutrients can lead to larger yields while at the same time, improving biodiversity conservation and the quality of forage.

High nature value (HNV) grasslands in mountain areas are important ecosystems for biodiversity maintenance and offer a multitude of ecosystem services, but they are constantly threatened by abandonment or intensive fertilization. The aim of this study was to assess the effects of organic and mineral fertilization, under mulching and abandonment scenarios, on the floristic composition and diversity of Nardus stricta-dominated grasslands located in the North-Eastern Carpathians (Romania). The field experiment included 11 variants (control, low, moderate, and high inputs), analyzed as communities with cluster, ordinations, indicator species, and α indices. The results showed a clear separation of communities along the input gradient, from the oligotrophic grassland dominated by Nardus stricta (control variant) to mesotrophic/eutrophic communities dominated by Dactylis glomerata, Festuca pratensis, and Trifolium pratense at moderate and high inputs. Moderate fertilization (10–20 t ha⁻¹ manure; N₅₀P₅₀K₅₀–N₁₀₀P₁₀₀K₁₀₀) maximized species richness (37–38 species), Shannon diversity (H′ = 2.5–2.6), and evenness (E = 0.70–0.75). High inputs reduced diversity and favored competitive grasses. Indicator species analysis highlighted a multitude of species that show the plant communities’ response to adaptive management. Moderate fertilization provides a viable trade-off between productivity and biodiversity, while abandonment or overfertilization accelerates biodiversity loss.

The pastoral area of Romania, covering of over 4.8 million ha, has been influenced, over the last decades, by natural and human factors, which affect the normal functioning of the grassland ecosystem. The aim of this paper is to point out the dynamics of phytocoenotic biodiversity, as a result of applying grassland technical measures, in order to improve the yield and quality of grassland ecosystems with minimum effects on the environment. Therefore, the main aim of our study is to establish a positive relationship between biodiversity and the optimum quantity of organic fertilizers, which would improve the quality and quantity of the yield, without diminishing the floristic biodiversity. In the case of the studied grasslands, the phytocenotic biodiversity is influenced by the type of fertilization, the used rates and by the soil and climatic conditions. These grasslands may be improved by manure fertilization and reasonable usage, if proper management is applied. In Gradinari, Caras-Severin county, the dominant species are Festuca rupicola and Calamagrostis epigeios, in Magurele, Brasov county, Agrostis capillaris, Festuca pratensis, Poa pratensis and Trifolium repens, and in Pojorata, Suceava county, Agrostis capillaris, Trisetum flavescens, Trifolium repens and T. pratense species. The highest number of identified species (43) has been recorded by the meadow made up of Agrostis capillaris and Festuca rubra, from Pojorata, Suceava county.

In order to obtain more data concerning the influence of fertilizers (organic and mineral) on different forage plants in the northeastern Romanian grassland, the mass fractions of 14 essential, enzymatic, or toxic elements were determined by instrumental neutron activation analysis together with the amount of crude proteins, ash, fibers, as well as fat ether extract. The final results showed a significant variance in the content of analyzed elements on organic as well as on mineral fertilized experimental plots. At the same time, increased content of crude protein and fat ether extract was evident in fertilized grasses for all applied fertilizers, while other global indicators such as neutral and acid fibers of sulfuric lignin content decreased, suggesting significantly higher nutritional values for fertilized forage plants.

The history of spread and habitat preferences during invasion of four alien species of Lepidium in Romania, namely L. densiflorum, L. oblongum, L. sativum, and L. virginicum are presented in this paper. The floristic records of these species, collected between 1816 and 2013, were used in the study. L. sativum was sporadically mentioned by earlier botanic references, as a casual alien plant in ruderal places. L. oblongum was reported from a single locality, but it may be considered a potential invader of ruderal habitats from southern regions. For L. densiflorum and L. virginicum, distribution maps were made in the Universal Transverse Mercator system, and exponential regression models were fitted to the cumulative number of records against time. Both L. densiflorum and L. virginicum are invasive in Romania, and their spread was initiated at the middle of last century. The slope of invasion curves, which was used as a measure of the invasion rate, did not differ significantly between the two invasive species. Although both L. densiflorum and L. virginicum were first reported in the North-West of the country, they followed different paths of migration in Romania. Ruderal habitats associated with railways played an important role in the invasion process of both species, but invaded habitats became more diversified over the time. Among the four species, only L. densiflorum tends to invade agricultural crops.

High Nature Value (HNV) mountain grasslands in the Eastern Carpathians are sensitive to fertilization intensification. This study evaluated the effects of organic and mineral inputs on the floristic composition, vegetation types, and diversity of an oligotrophic grassland with Nardus stricta in a long-term experiment established in 2002, with results presented here from three recent experimental years (2022–2024) with nine variants (unfertilized control, 10–30 t ha⁻¹ manure applied in autumn/spring, and 200–300 kg ha⁻¹ nitrocalcar). Vegetation composition was analyzed using hierarchical classification, PCoA, MRPP, Indicator Species Analysis, and α-diversity indices (species richness, Shannon, Simpson, and evenness). The results revealed six floristic types arranged along a clear trophic gradient, ranging from oligotrophic to eutrophic communities. Specifically, low-moderate manure treatments (10–20 t ha⁻¹) simultaneously maximized community diversity and balance, maintaining a rich core of oligotrophic and mesotrophic species. Conversely, high doses of manure (30 t ha⁻¹) and mineral fertilization led to a marked reduction in species richness and the dominance of a few competitive-grass species. Ultimately, this study demonstrates that moderate organic fertilization is compatible with the adaptive management of HNV grasslands, whereas intensive mineral fertilization is incompatible with conservation objectives.