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High nature value (HNV) grassland systems are increasingly important for the ecosystem services they provide and for their socio-economic impact in the current constant-changing context. The aim of our paper is to evaluate the long-term effect of organic fertilizers on HNV systems in the Apuseni Mountains, Romania. As an objective we want to identify the optimal intensity of conservation management and its recognition based on indicator value plant species. The experiments were established in 2001 on the boreal floor and analyze the effect of a gradient of four organic treatments with manure. Fertilization with 10 t ha−1 manure ensures an increase in yield and has a small influence on diversity, and could be a real possibility for the maintenance and sustainable use of HNV. Each fertilization treatment determined species with indicator value that are very useful in the identification and management of HNV. The indicator species are useful in forecasting the fluctuations and successions in grasslands, determined by the modification of the dominance-codominance ratio and the real coverage of each species.

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Although essential for achieving high crop yields required for the growing population worldwide, nitrogen, (N) in large amounts, along with its inefficient use, results in environmental pollution and increased greenhouse gas (GHG) emissions. Therefore, improved nitrogen use efficiency (NUE) has a significant role to play in the development of more sustainable crop production systems. Considering that wheat is one of the major crops cultivated in the world and contributes in high amounts to the large N footprint, designing sustainable wheat crop patterns, briefly defined by us in this review as the 3 Qs (high quantity, good quality and the quintessence of natural environment health) is urgently required. There are numerous indices used to benchmark N management for a specific crop, including wheat, but the misunderstanding of their specific functions could result in an under/overestimation of crop NUE. Thus, a better understanding of N dynamics in relation to wheat N cycling can enhance a higher efficiency of N use. In this sense, the aim of our review is to provide a critical analysis on the current knowledge with respect to wheat NUE. Further, considering the key traits involved in N uptake, assimilation, distribution and utilization efficiency, as well as genetics (G), environment (E) and management (M) interactions, we suggest a series of future perspectives that can enhance a better efficiency of N in wheat.

Semi-natural grasslands are particularly important in mountainous areas of Romania, being the only source of forage for many farmers. The aim of this study was to investigate the changes in forage quantity and quality as a result of Urea Ammonium nitrate (UAN) liquid fertilization. The experiment was carried out in the eastern part of Apuseni Mountains, Romania on a Festuca rubra L.-Agrostis capillaris L. grassland located at 1240 m altitude. Studies were made over three years of experimental trial (2014–2016) and covered four experimental plots in three replicates, as follows: V1–control plot, unfertilized; V2–plot fertilized with 50 kg UAN ha−1 year−1; V3–plot fertilized with 75 kg UAN ha−1 year−1, and V4–plot fertilized with 100 kg UAN ha−1 year−1. The experimental plots were harvested once per year and the botanical composition, dry matter yield and forage quality were assessed. Our results showed important changes in forage quantity, quality and diversity as a result of UAN fertilization. Starting from the second experimental year the dominance/co-dominance ratio changed favoring the species from Poaceae family. Dry matter increased as a result of UAN fertilization but forage quality was negatively affected by the higher percentage of participation of species from other botanical families which have higher crude fiber content and lower crude protein. Based on our results we recommend moderate fertilization with UAN up to 50 kg UAN ha−1 year−1 for semi-natural grasslands located in soil-climatic conditions similar to those in our experiment.

The present study was carried out to isolate and to investigate biochemical characteristics of twenty rhizobacteria strains from red clover (Rhizobium trifolii) and alfalfa (Sinorhizobium meliloti). The result of the study showed a low diversity in morphological, physiological and symbiotic properties among the rhizobial strains. Phenotypically all isolated strains had the same colony morphology conical with a smooth margin, the color and texture was watery to translucent. The isolates were fast-growing and failed to absorb Congo red. API 20NE and API 20E showed a negative reaction for the reduction of nitrate in RtS1, RtR2, and positive for SmM1, SmM2. The reaction was positive for β-galactosidase, β-glucosidase and negative for urease, arginine dihydrolase, for all rhizobial isolates. Carbon sources: glucose, arabinose, mannose,mannitol, maltose, were also positive for all strains. Rhizobial strains utilized a wider range of carbohydrates and this may be a helpful tool for the characterization of the isolates.

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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.