Format

Send to

Choose Destination
See comment in PubMed Commons below
Sci Total Environ. 2014 Apr 1;476-477:745-56. doi: 10.1016/j.scitotenv.2013.05.056. Epub 2013 Jun 20.

Least Disturbed Condition for European Mediterranean rivers.

Author information

1
Institute of Marine Research, IMAR-CMA, Dept. of Life Sciences, University of Coimbra, Portugal. Electronic address: mjf@ci.uc.pt.
2
Universidade Técnica de Lisboa, Instituto Superior de Agronomia, Centro de Estudos Florestais, Portugal.
3
Department of Biology and GeoBioTec, University of Aveiro, Portugal.
4
Portuguese Environmental Agency (APA, I.P.), Portugal.
5
Institute of Marine Research, IMAR-CMA, Dept. of Life Sciences, University of Coimbra, Portugal.
6
CNR-IRSA Water Research Institute, Brugherio, Italy.
7
Department of Plant Biology, University of Barcelona, Spain.
8
IRSTEA Bordeaux-Cestas, UR REBX, France.
9
Water Development Department, Ministry of Agriculture, Natural Resources and Environment, Cyprus.
10
IRSTEA Lyon, UR MALY, France.
11
Department of Biology, Biotechnical Faculty, University of Ljubljana, Slovenia.
12
National Health Institute, Rome, Italy.
13
Department of Biology, University of Patras, Patras, Greece.
14
ENEA Saluggia Research Center, Saluggia, Italy.
15
Catalan Water Agency, Spain.
16
Department of Ecology, University of Barcelona, Spain.
17
Institute of Aquatic Ecology, University of Girona, Spain.
18
Catalan Institute for Water Research (ICRA), Spain.
19
Institute for Water of the Republic of Slovenia, Slovenia.
20
University of Porto, Department of Biology, Portugal.

Abstract

The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference sites (929 records) from seven countries, sampled for invertebrates, diatoms and macrophytes was used. The analyses of reference sites showed that small (catchment <100 km(2)) siliceous and non-siliceous streams were mainly affected by channelization, bank alteration and hydropeaking. Medium-sized siliceous rivers were the most affected by stressors: 25-43% of the samples showed at least slight alterations regarding channelization, connectivity, upstream dam influence, hydropeaking and degradation of riparian vegetation. Temporary streams were the least affected by hydromorphological changes, but they were nevertheless affected by alterations in riparian vegetation. There were no major differences between all permanent stream types regarding water quality, but temporary streams showed lower values for oxygenation (DO) and wider ranges for other variables, such as nitrates. A lower threshold value for DO (60%) was determined for this stream type and can be attributed to the streams' natural characteristics. For all other river types, common limits were found for the remaining variables (ammonium, nitrate, phosphate, total P, % of artificial areas, % of intensive and extensive agriculture, % of semi-natural areas in the catchment). These values were then used to select the list of reference sites. The biological communities were characterized, revealing the existence of nine groups of Mediterranean invertebrate communities, six for diatoms and five for macrophytes: each group was characterized by specific indicator taxa that highlighted the differences between groups.

KEYWORDS:

Diatoms; Invertebrates; Least-disturbed conditions; Macrophytes; Mediterranean rivers; Thresholds

PMID:
23791044
DOI:
10.1016/j.scitotenv.2013.05.056
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center