WP 18: Spacial scale study
Objectives
To estimate how ecosystem biodiversity and different indicator groups can be used for assessing the ecological status of streams and what spatial scale is relevant. To provide complete sets of data from sites of medium-sized, deeper lowland streams from Ecoregion 15 (Baltic), so as to incorporate in EU system of inter-calibration of methods, integration of data from different taxonomic groups, standardisation of their application to ecological assessment of river quality. To contribute to the progress of implementation of methodologies of ecological integrity assessment and monitoring under WFD approach in Latvia.
Methodology/work description
For the purposes of this project, a nested hierarchical propose will be used (catchment area > streamreach > riffle > habitat) for studies of stream biodiversity in accordance with spatial scale. Also medium-sized, deeper lowland streams of Ecoregion 15 are recognised for the assessment of different stages of degradation by organic pollution. The acquisition of existing data and selection of sampling sites for data set for these objectives will be carried out. Data for cross-comparisons and the preparation of standards for Europe in accordance with WFD will be acquired.
The specific of the number and type of sites to be sampled are as follows:
- Three streams from three selected catchments with a high ecological status will be sampled. Within each stream three reaches will be sampled for studies of fishes and macrophytes.
- Five separate samples aggregated to one sample will be taken in each of three riffles in every reach for the investigations of diatoms and benthic macrofauna for spatial scale studies.
- In one stream of each catchment area one of the riffles will be intensively tested for the assessment of within-riffle variability by taking three aggregated replicate samples of benthic macroinvertebrates and diatoms. The benthic macrofauna will also be studied in stream edges and pools, i.e., two additional habitats. One intensively studied riffle in each catchment will also be a core stream sampling point.
- For core stream type 2 in Ecoregion 15 (represented by territory of Latvia) eight reference sites with no stress (Ecological Status = high) and four sites for three ecological grades of organic pollution ecological stress (Ecological Status = 'Good', 'Moderate', 'Poor' and 'Bad') will be sampled in accordance with Workpackage 7
The following samples will be taken:
- Electro-shocking of fish and inventory of macrophytes will be conducted within each site for studies of spatial scale biodiversity and different stages of degradation. Fishes and macrophytes will be sampled in only one season (summer).
- Fish surveys will be undertaken using the proposed CEN standard CEN/TC230/WG2/TG4/N8. Identification and measurement of fish will take place at the bank side, if possible. Identification will always be to species level.
- Standardised macrophyte surveys will be undertaken in summer only, using MTR (Mean Trophic Rank) and/or equivalent European Member State standard protocols.
- Diatoms will be sampled using the standard TDI (Trophic Diatom Index) protocol.
- Macroinvertebrate samples will be taken according to AQEM standard protocol at all sampling sites. Sampling for spatial scale study will be done in summer. Studies of stress factors impact will be sampled in two seasons (spring and autumn).
- Other 'macroinvertebrate method' for the purpose of method inter-calibration will be Latvian Standard LVS 240:1999 (Water quality - Operative evaluation of biological quality of small stream by saprobity index of macro-zoobenthos community).
- River corridor/habitat surveys will be undertaken using RHS (River Habitat Survey) protocols. River Habitat Survey is a field based recording systems, supplemented by additional time variant information acquired from cartographic/GIS sources. For each sampling site the AQEM site protocol containing 130 hydrological, abiotic and morphological parameters will be completed to gain comparable information on the ecological status.
The sampling, survey and sample processing protocols to be used are all standard techniques currently in use in one or more EU Member States, NAS or research projects and each are prescribed in detailed, publicly available manuals. Sorting and identification macro-invertebrate samples will be undertaken in the laboratory using prescriptive procedures in standard manuals. Identification will be to the best achievable and should be to species level wherever possible.
The identification of the phytobenthos samples will be carried out by a Polish NAS partner.
