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Benthic invertebrate communities, through the nature of their life cycle, are particularly sensitive to the stress caused by polluting discharge. Due to this aspect, the characteristics of the living environment act as an effective tool for detecting and reducing stress conditions. The present study was undertaken to investigate the density, numerical abundance and frequency of the benthic macro invertebrates in four different sampling points of the Bega River in the area of Timișoara and its surroundings, in order to indirectly evaluate the overall water quality condition and trends in the aquatic environment. A total of 20 water samples from each location were seasonally collected, processed and screened for the presence of benthic communities using the specific determination keys. Overall, ten groups of invertebrates including Oligochaeta subclass, Diptera order (larvae of the family Chironomidae, Ceratopogonidae and Tipulidae), Lamelibranchiata, Hirudinea, Nematoda and Gastropoda classes; and Trichoptera, Isopoda, Coleoptera and Odonata orders were identified, with differences in the monitored parameters according to sampling points and seasons. The recorded values of the monitored parameters demonstrated different effects in urban towards rural environment, and the resulted consequences can be represented by undesired noticeable changes on the natural environment. The self-purification phenomenon of the Bega River is developing, with quite good results observable at the level of the monitored two sampling points located downstream from Timișoara. However, the overall water quality condition, is still not superior, fact proved by the absence of the most sensitive invertebrate groups. [ABSTRACT FROM AUTHOR]

The anthropic impact, having various forms, negatively changes the parameters of water quality and disturbs the living environment of benthic macroinvertebrates. The purpose of the present study is to present how the main sources of pollution influence the way of life of the benthic macroinvertebrates community. 20 quantitative benthic samples were collected from different benthic areas of the Bega River water during from June 2014 to February 2017. In addition to identify all the changes that occur in the structure of macroinvertebrates community due to the activities performed by the human population. For the study to lead to conclusive results, samples were collected upstream and downstream from the main sources of pollution. Macroinvertebrates identified the macroinvertebrates and performed tests to determine the density, abundance and frequency of the samples. Based on these data, it is observed that, the presence of benthic macroinvertebrates that are sensitive to pollutants and higher-quality water in the upstream segment waters sector compared to the waters of the central segment where we identified benthic macroinvertebrates that prefer a polluted living environment. In the downstream segment, we could see that the river has a better quality, because naturally flowing on a long distance, allows an improvement in water quality through the self-purification process emphasized by the occurrence of some sensitive groups to pollution. [ABSTRACT FROM AUTHOR]

Festuca Arundinacea is one of the most valuable fodder plants, successfully grown in Romania. Festuca Arundinacea crop quality depends on the quality of seeds, therefore vigour tests are essential, as they describe the behaviour of seeds under various growth conditions. The paper aims at assessing the quality of Festuca Arundinacea seeds and the efficiency of the methods to determine them. The biological material used consisted of Festuca Arundinacea seeds, Palma variety, stored in uncontrolled conditions, one year after harvest. The present paper assesses several seed parameters: total germination, normal seedlings, abnormal seedlings, dead seeds, seed weight, as well as the appearance of normal seedlings ( after 7 to 14 days) through three laboratory methods : BP (between paper) test ( VI, V2, V3, V4), sand S test (V5) and top of paper TP test (V6). Seed germination percentage for Palma variety ranged from 74% (V4) to 79% (VI and V6). Low germination is especially caused by the large number of dead seeds, the main cause being the improper storage conditions. According to the results of this experiment, cluster analysis showed the efficiency of the BP test, without pre-cooling, and of TP test, in emphasizing the quality characteristics of Festuca arundinacea seeds, Palma variety. Sand test S, which is actually the hardest to run, is less suitable for this research. [ABSTRACT FROM AUTHOR]

An abstract of the article "Dynamic of Hill Grassland Floristic Composition in Spring on the Effects of Fertilizers," by Alexandru Moisuc and colleagues is presented.