An integrated assessment of Baltic Sea ecosystems

Transcription

1 An integrated assessment of Baltic Sea ecosystems Swedish Institute of the Marine Environment Annual Conference Lena Bergström, SLU-Aqua

2 Current policy supports an ecosystem-based management

3 Ecosystem-based management is based on integrated ecosystem monitoring and assessment has management strategies for entire systems, not only for components of the system considers interactive and cumulative effects

4 The full management cycle (Tallis et al. 2010, Marine Policy)

5 Identify main goals and critical ecosystem components The full management cycle (Tallis et al. 2010, Marine Policy) Identify indicators for trackning state Identify minimum levels how much is too much Identify susceptible components and main hazards Assess state Compare management options (by conceptual or quantative models) Monitoring (Convert areas from data poor to data rich)

6 A Baltic Example

7 The ICES/HELCOM Working Group on Integrated Assessments of the Baltic Sea (WGIAB) a forum for developing and combining ecosystem based management efforts for the Baltic Sea

8 The main tasks of WGIAB in Main focus for this talk 1) Conduct holistic ecosystem assessments based on datasets on biotic and abiotic monitoring variables in each basin and in selected coastal areas 2) Develop ecosystem modelling in the assessment framework assessments of single species based on ecosystem indicators, studies on environmental forcing on species and food-webs (ensemble modelling), ecological and economic models 3) Develop adaptive management strategies for the different Baltic Sea ecosystems developing the full Integrated Ecosystem Assessment cycle, contributing to present fish stock assessment

9 Study areas For these areas, multivariate data sets are continuosly updated NB. Many areas are of potential common interest with national programs and reporting Studies on coastal areas initiated in 2011, to be developed further

10 An example of integrated trend analysis - the Kvädofjärden Coastal Baltic sea area

11 Step 1. Data collation Data series for 12 abiotic and 12 biotic variabels were included Time period studied: Analyses were performed on normalised data Variables representing salinity, temperature, ph, offshore nitrate, offshore phosphate, nutrient loading from land, fishing pressure, 4 zoobenthic species, 6 fish species and grey seal

12 Overview of temporal trends in each variable

13 Step 2. Multivariate ordination (PCA) 15,6% start end 25,4%

14 Here, ordination was performed separately for biotic data only Recent years characterised by high levels of grey seal, perch and white bream

15 Step 3. Discontinuity analyses Are the changes continuous over time or are they more pronounced at some points in time? Important for Understanding ecosystem processes (trophic interactions) Identifying the scale of change (by comparing areas) For target setting, eg to identify reference years with similar external preconditions

16 Chronological clustering In this example, the observed changes where mainly continuous, discontinuous patterns where identified only at alpha = 0.2

17 General overview, main changes in studied off shore ecosystems Katte Gat Öresund Central Baltic Sea Based on Chronological clustering at alpha = 0.05, Ref. ICES WGIAB 2010

18 General overview, main changes in studied off shore ecosystems (cont.) Gulf of Riga Gulf of Finland Bothian Sea Bothnian Bay

19 Summary, usefulness of ITA Integrated analysis of monitoring data Characteristic features of different years Relative changes over time Identify management targets Define reference years Potential tool for balancing conflicting targets Identify the most influential pressures on ecosystem changes Support for further modelling steps Provide ecosystem indicators to support sectorial management, eg fish stock assessments

20 Interested in joining the 2012 meeting? The ICES/HELCOM Working Group on Integrated Assessments of the Baltic Sea (WGIAB), chaired by Martin Lindegren, Denmark, Maciej Tomczak, Sweden, and Lena Bergström, Sweden, will meet in Stockholm, April 4-8, 2012 For an invitation, please contact any of the chairs The meeting will be held back-to-back with the corresponding North Sea group (WGNOSE), which is chaired by Gerd Kraus and Christian Möllmann

21 Thank you for your attention!