Search results for "Richne"

Forest drainage: a threat to benthic biodiversity of boreal headwater streams?

1998

1. Forest drainage, including mainly ditching of waterlogged peatlands in order to increase wood growth, has caused substantial changes in the hydrology and water quality of Finnish streams. However, knowledge on the ecological impact of these changes is poor. This paper studies the potential impact of forest drainage, catchment characteristics and habitat factors on the water quality and benthic macroinvertebrates in headwater streams of the River Isojoki, western Finland. An intensive programme of water sampling was carried out at nine study sites, while zoobenthic samples covered a total of 18 streams. 2. According to multivariate regression models concentrations of aluminium and suspend…

Groundwater biodiversity in Europe

2009

18 páginas, 7 figuras, 4 tables et al

The component helminth community in six sympatric species of Ardeidae.

2005

We studied the helminth communities in 6 sympatric species of Ardeidae (Ixobrychus minutus (Linnaeus, 1766), Nycticorax nycticorax (Linnaeus, 1758), Bubulcus ibis (Linnaeus, 1758), Egretta garzetta (Linnaeus, 1766), Ardea cinerea (Linnaeus, 1758), and Ardea purpurea (Linnaeus, 1766)) from "La Albufera de Valencia," Spain. The survey revealed 13 species of helminth parasites: 5 digeneans, 2 cestodes, and 6 nematodes. The component helminth communities of the Ardeidae examined are depauperate and conform to the pattern typically found in isolationist communities, probably because of their high trophic dependence on a few prey species. Evenness was positively correlated with richness and abund…

Cost-Efficiency of Decaying Wood as a Surrogate for Overall Species Richness in Boreal Forests

2006

Decaying wood is one of the most important elements for species richness in boreal forests. We tested how well reserve selection based on the amount and quality of decaying wood results in a representation of four ecologically different taxa (beetles, birds, wood-inhabiting fungi, and vascular plants). We also compared the cost-efficiency of the use of dead-wood indicators with comprehensive species inventory. Our database included 32 seminatural old-forest stands located in northern Finland. Decaying wood was a relatively good indicator of saproxylic species but not overall species richness. Even though dead wood did not reflect accurately overall species richness, our results indicated th…

Follow-up trends of parasite community alteration in a marine fish after the Prestige oil-spill: shifting baselines?

2008

This study evaluates the follow-up trends in the composition and structure of the parasite communities in the marine sparid Boops boops after the Prestige oil-spill. A total of 400 fish comprising 11 seasonal samples was analyzed from three impacted localities on the Atlantic coast of Spain. A large number of parasite species was recovered only after the spill thus suggesting a substantial alteration of the marine food webs. Post-spill communities exhibited higher richness and abundance due to the significant changes in the abundance of the common species, the latter indicating accelerated parasite transmission rates. Multivariate analyses at two nested scales detected a directional trend i…

Plant diversity effects on the water balance of an experimental grassland

2014

In the literature, contrasting effects of plant species richness on the soil water balance are reported. Our objective was to assess the effects of plant species and functional richness and functional identity on soil water contents and water fluxes in the experimental grassland of the Jena Experiment. The Jena Experiment comprises 86 plots on which plant species richness (0, 1, 2, 4, 8, 16, and 60) and functional group composition (zero to four functional groups: legumes, grasses, tall herbs, and small herbs) were manipulated in a factorial design. We recorded meteorological data and soil water contents of the 0·0–0·3 and 0·3–0·7 m soil layers and calculated actual evapotranspiration (ETa)…

2005

Las Tablas de Daimiel National Park is a semiarid, hypertrophic wetland located in La Mancha (Ciudad Real, Central Spain). During the period 1996-2002 we carried out monthly samplings at three sites of Las Tablas. Thirty five taxa of Euglenophytes of the genera Astasia (1 taxon), Euglena (15), Lepocinclis (6), Phacus (9), and Trachelomonas (4) were identified. Six taxa are new records for Spain. Abundance, species richness, species groups and absolute and relative biomass of Euglenophytes widely fluctuated spatio-temporally in Las Tablas, without any statistically significant relationship (P > 0.05) with organic carbon (either particulate or dissolved), which has been long considered the ma…

What is a tree in the Mediterranean Basin hotspot? A critical analysis

2019

Background: Tree species represent 20% of the vascular plant species worldwide and they play a crucial role in the global functioning of the biosphere. The Mediterranean Basin is one of the 36 world biodiversity hotspots, and it is estimated that forests covered 82% of the landscape before the first human impacts, thousands of years ago. However, the spatial distribution of the Mediterranean biodiversity is still imperfectly known, and a focus on tree species constitutes a key issue for understanding forest functioning and develop conservation strategies. Methods: We provide the first comprehensive checklist of all native tree taxa (species and subspecies) present in the Mediterranean-Europ…

Spatial Representation of Plant Diversity at Geographical Scale: The Italian Experience

2021

The first attempts to draw up plant biodiversity maps in Italy are identified, some of which represent re-workings of data collected for chorological atlases of geographic areas of different extents. These were based particularly on the UTM grid, introduced and codified in Italy by Pignatti [6]. The limited examples made in Italy concern regional, provincial or district areas, some also in protected natural areas. As examples considered original, the maps developed at the Phytotaxonomy and Phytogeography Laboratory of the University of Palermo are presented. These involve the province of Palermo, the Madonie Natural Park in Palermo province, and the eastern Sicani mountains. The map of this…

A Plant Sociological Procedure for the Ecological Design and Enhancement of Urban Green Infrastructure

2021

AbstractUrban green infrastructure could represent an important mean for environmental mitigation, if designed according to the principles of restoration ecology. Moreover, if suitably executed, managed and sized, they may be assimilated to meta-populations of natural habitats, deserving to be included in the biodiversity monitoring networks. In this chapter, we combined automatised and expert opinion-based procedures in order to select the vascular plant assemblages to populate different microhabitats (differing in terms of light and moisture) co-occurring on an existing green roof in Zurich (Switzerland). Our results lead to identify three main plant species groups, which prove to be the …