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Several studies demonstrated that abandonment changes the functional composition of grasslands; nevertheless, little is known about the effects of grassland abandonment on the flowering-related functional pattern. We hypothesized that invasion by tall grasses affects this pattern. We counted the number of flowering shoots per species at five times during the growing season, in 80 plots placed in mown and in abandoned grasslands (central Apennines), and assessed the differences in the trait composition of flowering species between the two treatments. The selected traits were linked to resource acquisition and stress tolerance strategies. Our results indicated that abiotic environmental control is prevalent in determining the phenological pattern in both conditions and in accordance with the phenological “mid-domain hypothesis”. We demonstrated that when the dominant species is a tall grass with competitive behaviour, the magnitude of this phenomenon is amplified due to the abiotic changes yielded by the tall grass invasion. Indeed, in the central and late phases of the growing season (when invasive tall grasses are growing and blooming), abandoned grasslands were marked by a set of traits devoted to stress tolerance or underlying a long reproductive cycle or linked to competition for light. [ABSTRACT FROM AUTHOR]

In the Peruvian highlands, climate change and inadequate management are causing land degradation and collapse of the pastoral system. Our research project was aimed at assessing the impact of grazing on dry Puna ecosystem, as understanding and predicting vegetation changes in harsh environments in the face of different disturbance regimes is required for aware and effective management. The study area was the Salinas and Aguada Blanca National Reserve. Two experimental areas were selected, characterized by deep soils with gentle slopes and by shallow soils with steeper slopes. In each area, sites with low and high disturbance regimes were identified, and vegetation was sampled using 10 × 10 m plots. The results indicated that the environmental constraints have a marked influence on the species composition, while disturbance quantitatively affects diversity. The floristic changes observed under different disturbance intensities are mainly related to the functional differentiation of the plant communities and to the decrease in vegetation cover. These processes pose a serious risk to the livelihood of the local people, because they can lead to the loss of biodiversity and economic value of pastures, as well as to soil erosion. [ABSTRACT FROM AUTHOR]

The present study examined a sub-Mediterranean pastoral system in the central Apennines (Italy) with a long history of grazing, where winter cold stress is alternated with summer drought stress. The research goals were to ascertain whether different floristic structures correspond to different stress conditions (xeric and semimesic), and whether peculiar functional plant traits (such as avoidance and tolerance mechanisms) respond to stress/disturbance intensities, and understand how vegetation reacts to changeable livestock pressure (through floristic and plant trait variations). Cluster analysis indicated that separate communities develop under different stress intensities. Other analyses highlighted how avoidance strategies predominate within the pastoral system. Observations of grazed and ungrazed patches conducted in 10-m transects revealed spiny cushion formation in semimesic grassland, where a brief period of overgrazing occurs in late summer, causing variations in plant community structure. All these results confirm the importance of historical grazing and current land use, showing how small disturbances and stress variations cause ecosystem responses. Best practices for management were identified. In xeric conditions, it is advisable that the intensity of disturbance be lessened, while in semimesic grassland overgrazing should be forbidden during the dry period, because it could facilitate the development of spiny patches, and subsequent spread of Brachypodium rupestre. [ABSTRACT FROM AUTHOR]