Flow-MER research - MARXAN identification of refuge habitat in the Murray-Darling Basin

The Flow-MER research project identification and characterisation of refuge habitat research project applied systematic conservation planning using MARXAN to identify wetlands in the Murray Darling Basin (MDB ) that may act as climate refugia.  Refuge habitats were identified as wetlands with the least deviation in water levels, that were the most feasible to manage and could supported target species, ecosystems and functions.  MARXAN uses a simulated annealing algorithm to identify a set of planning units that maximises the representation of ecological asset, while aiming to capture a defined target for each asset and minimise ‘cost’. The ‘cost’ of a planning unit was weighted by its capacity to act as a refuge (dryness anomaly), catchment condition and connectivity (River Disturbance Index) and management feasibility (previous environmental water delivery).

The two data tables join to the Australian National Aquatic Ecosystems (ANAE) v3.0 Classification of the Murray-Darling Basin (2021)  using the mapped wetland polygon UID attribute.
1.	marxan_cost_managable_floodplain.csv contains MARXAN cost values and final solution set for all lakes and palustrine wetland within scope for water management (on the managed floodplain) in the MDB.
2.	marxan_cost_wetlands_water_mgmnt_2014-2020.csv contains the MARXAN attributes and solution for the subset of wetlands that have previously received Commonwealth environmental water during the 6 year period 2014-2020.

The CEWH’s Flow-MER program examines the contribution of Commonwealth environmental water to the environmental objectives of the Basin Plan 2012 (Basin Plan) and is assisting the CEWH to demonstrate environmental outcomes and adaptively manage the water holdings.

Wetlands and lakes are refuges for plants and animals during droughts and other hard times. Maintaining refugia in the Murray–Darling Basin is a key objective of Commonwealth environmental water management.

### Project Report
Bennett J M, Brooks S, Bush A, Hitchcock J, Linke S (2023) Identifying and characterising refugia habitat for target organisms across the Murray–Darling Basin. Commonwealth Environmental Water Holder’s Science Program: Flow Monitoring, Evaluation and Research (Flow-MER). Department of Climate Change, Energy, the Environment and Water, Australia. 55pp.

### Data Citation
CEWH (2025) MARXAN Identification of refuge habitat in the Murray-Darling Basin. Flow-MER Program. Commonwealth Environmental Water Holder, Australian Government Department of Climate Change, Energy, the Environment and Water. Sourced from https://data.gov.au/data/dataset/flow-mer-research-marxan-refuge-habitat on [date-sourced].
###Acknowledgement

The Commonwealth Environmental Water Holder and Flow-MER program participants acknowledge the First Nations peoples as the Traditional Owners and Custodians of the lands, waterways and skies of the Murray-Darling Basin. We respect their continuing connection to culture and Country, and we thank them for their knowledge and science and the values reflected in these data.

Tags: CEWH, Commonwealth Environmental Water Office, Murray darling basin, environmental management, refuges
Organization: Commonwealth Environmental Water Holder