Runoff and Solute Outputs under Different Land Uses: Long-Term Results from a Mediterranean Mountain Experimental Station

Water availability and quality in Mediterranean environments are largely related to the spatial organisation of land uses in mountain areas, where most water resources are generated. However, there is scant data available on the potential effects of land use changes on surface water chemistry in the Mediterranean mountain region. In order to address this gap in the research, this study investigates the effects of various mountain Mediterranean land covers/land uses on runoff water yielded and water chemistry (solute concentrations and loads) using data from the Aísa Valley Experimental Station (Central Pyrenees) for a long-term period (1991–2011). Nine land covers have been reproduced in closed plots, including dense shrub cover, grazing meadows, cereal, fallow land, abandoned field, shifting agriculture (active and abandoned) and 2 burned plots (one burned in 1991 and the second one burned twice in 1993 and 2001). Results show that all solute concentrations differed among land uses, with agricultural activity producing significantly higher solute loads and concentrations than the other types. Two groups have been identified: (i) the lowest solute concentrations and the smallest quantities of solute loads are recorded in the dense shrub cover, the plot burned once (at present well colonized with shrubs), meadows and abandoned field plots; (ii) the plot burned twice registered moderate values and the highest solute concentrations and loads are found in cereal, fallow land and shifting agriculture plots. Water chemistry is clearly dominated by Ca2+ and HCO3− concentrations, whereas other solutes are exported in very low quantities due to the poor nutrient content of the soil. These results complete the information published previously on soil erosion under different land uses in this experimental station and help to explain the evolution of land cover as a consequence of shifting agriculture, cereal farming on steep slopes and the use of recurrent fires to favour seasonal grazing. They also suggest that promoting the development of grazing and cutting meadows is a good strategy to reduce not only soil erosion but also the loss of nutrients.

MATERIALS TO THE SPIDER FAUNA (ARANEI) OF THE BYKOVA SHEYA SITE OF THE “GALICH’YA GORA” NATURE RESERVE (LIPETSK REGION, RUSSIA)

<p>A total of 73 spider species from 15 families were recorded from the Bykova Sheya site of the “Galich’ya Gora” Nature Reserve (Lipetsk Region, Russia) in April – August 2011–2012. The material was collected thorough pitfall-trapping and sweep-netting. Four habitats were investigated: abandoned field on the upper interfluves (31 spider species), stony slope with the typical vegetation of calcareous grasslands (28 species), slope with shrub and fob-bunchgrass vegetation (35 species), and a floodplain meadow (38 species). Hand collecting in a forest shelterbelt and on the riverbank added eight species to the list. Two families, Gnaphosidae (15 species) and Lycosidae (13 species) were the most species-rich. Four registered species are regionally rare (<em>Gnaphosa taurica</em>, <em>Berlandina cinerea,</em> <em>Eresus kollari </em>and<em> Alopecosa solitaria</em>); the latter two can be considered as specific species of the ‘Bykova Sheya’ site. An annotated checklist and a brief description of the spider assemblages of different habitats are given.</p>

Effects of the penetration of Artemisia vulgaris L. into maize crops as a result of the use of reduced tillage

In recent years, a significant increase in weed infestation of agricultural crops with <em>Artemisia vulgaris </em>has been observed in the south-western region of Poland. The ease of migration of this expansive species results from the fact that it does not face competition from segetal weeds and therefore poses a great threat to the ecological balance. During the period 2008–2011, a floristic study was carried out using the Braun-Blanquet method in an abandoned field adjacent to a maize monoculture grown under two tillage systems: plough and ploughless tillage. These observations allowed an evaluation of the actual risk of spread of <em>Artemisia vulgaris </em>depending on tillage system. The vicinity of the abandoned field had a significant effect on the penetration of <em>Artemisia vulgaris </em>into maize crops. Higher numbers of individuals of this species were found under ploughless tillage compared to plough tillage, regardless of the distance from the field edge, and its increased competitive effects on <em>Viola arvensis </em>L. and <em>Veronica persica </em>L. could be observed. The lowest grain yield was obtained under ploughless tillage where the strong competitive effects of <em>Artemisia vulgaris </em>were observed even in the plot most distant from the abandoned field adjacent to the maize crop.