DISTURBING FLOWS: RECOVERY CAPACITY OF MACROINVERTEBRATE ASSEMBLAGE AND TRAITS TO FLOW EXTREMES Daniela P. Cortez 1, Prof. Ross Thompson 1, Dr. Ivor Growns 2 and Assist. Prof. Ben Kefford 1 1 Institute for Applied Ecology, University of Canberra, Australia 2 NSW Office of Water, Australia

BACKGROUND

Poff et al BioScience 47 FLOW REGIME Magnitude Frequency Duration Timing Rate of change WATER QUALITY ENERGY RESOURCES PHYSICAL HABITAT BIOTIC INTERACTIONS ECOLOGICAL CONDITION

Time Ecosystem condition Resistant Resilient EVENT/RESPONSE Disturbance

RESISTANCE: amount of disturbance a system can absorb & still remain within the same state or domain RESILIENCE: ability of an ecosystem to reorganise & renew itself when subject to disturbance

3 Elmqvist et al (2003). Front. Ecol. Environ. 1(9), HUMAN IMPACTS: altered capacity of ecosystems to buffer disturbance 3

Time Ecosystem condition EVENT/RESPONSE Abstraction Resistant Resilient Disturbance

GAPS IN KNOWLEDGE 1 Woodward et al (2015). Freshwater Biol. 60, Reiss et al (2009). Trends Ecol. Evol. 24, Responses in absence of environmental flows – disturbance (droughts, floods) Very few studies have tracked how species traits respond to extreme events in the field 1 – Responses of community structure and ecosystem function to disturbances are essential 2

EFFECT OF ABSTRACTION ON COMMUNITY COMPOSITION EFFECT OF ABSTRACTION ON RESISTANCE AND RESILIENCE TO DISTURBANCE RESEARCH AIMS

METHODS

RIVER C RIVER B RIVER A Subtropical humid forest (SCf) – US: Subtropical Division (230) – Middle east: sub-humid Mediterranean – Africa: subtropical lowland (sub)humid – Europe: swamp & fen forests (T), caucasian mixed hornbeam-oak forest (F7) US DS

Discharge (mL/day) IRRIGATION SEASON (8 MONTH PERIOD) BACKGROUND HYDROLOGY Dry Flood V. Dry

DISCHARGE WATER QUALITY HABITAT BENTHIC ALGAE MACROINVERTS Rapid bioassessment (Chessman 1995) Live-picking on site (1 hr) Identified to lowest taxonomic level – EPT to Genus min.

RESULTS

EFFECT OF ABSTRACTION ON COMMUNITY COMPOSITION RESEARCH AIMS

Abstraction (ppn. water allocated for irrigation) 1 – INV. TAXA RICHNESS Invert. Taxa Richness Dry Flood V. Dry BACKGROUND HYDROLOGY

Abstraction (ppn. water allocated for irrigation) 1 – INV. TAXA RICHNESS + 12 sp. + 5 sp. + 3 sp. -2 sp. - 8 sp.+ 1 sp. ~ 0 sp. +1 sp. + 5 sp. -7 sp. - 5 sp. Δ sp. - 4 sp. + 2 sp. Δ sp. - 6 sp. Δ Total Invert. Taxa Richness Dry Flood V. Dry BACKGROUND HYDROLOGY

– INVERT. ASSEMBLAGE PCO1 (log x+1) (40.8% of variation) PC02 (logx+1) (14.1% of variation) Dry Flood V. Dry ABSTRACTION BACKGROUND HYDROLOGY Low High

ASSEMBLAGES DRIVEN BY ABSTRACTION 1. HIGH ABSTRACTION SITES SIMILAR 2. LOW ABSTRACTION SITES MORE VARIABLE EFFECT OF ABSTRACTION ON COMMUNITY COMPOSITION

1 Chessman BC (2012). Journal of Biogeography 39, Figure 1 (a): Map of New South Wales and Australian Capital Territory showing the stream network and locations sampled for macroinvertebrates between Rheophily trait calculated on hydraulic score 1 – 0 for pool edge-waters, still waters – 1 for glides – 2 for runs, – 3 for riffles, – 4 for rapids and – 5 for cascades and waterfalls

3 – RHEOPHILY TRAITS PCA1 PCA2 Dry Flood V. Dry BACKGROUND HYDROLOGY ABSTRACTION Low High

STRONGER RELATIONSHIPS BETWEEN LOW AND HIGH ABSTRACTED SITES LOW (MORE LENTIC) CHARACTER = HIGHER ABS. HIGHER (MORE LOTIC) CHARACTER = LOW ABS. EFFECT OF ABSTRACTION ON COMMUNITY COMPOSITION

EFFECT OF ABSTRACTION ON RESISTANCE AND RESILIENCE TO DISTURBANCE RESEARCH AIMS

5 -5 PCA2 (logx+1) 10 Dry Flood V. Dry BACKGROUND HYDROLOGY RESISTANCE: hypothetical PCoA1 (log x+1) ABSTRACTION Low High

5 -5 PCA2 (logx+1) 10 Dry Flood V. Dry BACKGROUND HYDROLOGY RESILIENCE: hypothetical PCoA1 (log x+1) ABSTRACTION Low High -5

– INVERT. ASSEMBLAGE PCoA2 (logx+1) PCoA1 (log x+1) Dry Flood V. Dry BACKGROUND HYDROLOGY ACTUAL DATA ABSTRACTION Low High

EFFECT OF ABSTRACTION ON RESISTANCE AND RESISTANCE TO DISTURBANCE NO STRONG RELATIONSHIP BETWEEN ABSTRACTION AND AMOUNT OF COMMUNITY CHANGE IN RESPONSE TO NATURAL FLOW EVENTS

EFFECT OF ABSTRACTION ON COMMUNITY COMPOSITION EFFECT OF ABSTRACTION ON RESISTANCE AND RESILIENCE TO DISTURBANCE RESEARCH AIMS

FLOW WATER QUALITY HABITAT BENTHIC ALGAE MACROINVERTS PHD THESIS: Water abstraction effects on Australian river ecology: monitoring, management & implications

THANKS AND APPRECIATION.. Institute for Applied Ecology, Water Science UNIVERSITY OF CANBERRA, AUSTRALIA Bill Williams Travel Scholarship AUSTRALIAN SOCIETY FOR LIMNOLOGY Peter Cullen Postgraduate Award, NSW GOVERNMENT, WITH DPI WATER

Abstraction (% water allocated for irrigation) 1 – INV. TAXA RICHNESS + 12 sp. + 5 sp. + 3 sp. -2 sp. - 8 sp.+ 1 sp. ~ 0 sp. +1 sp. + 5 sp. -7 sp. - 5 sp. Δ sp. - 4 sp. + 2 sp. Δ sp. - 6 sp. Δ Total Invert. Taxa Richness Dry Flood V. Dry BACKGROUND HYDROLOGY

A – INVERT. ASSEMBLAGE PCO1 (log x+1) (40.8% of variation) PC02 (logx+1) (14.1% of variation) Dry Flood V. Dry ABSTRACTION BACKGROUND HYDROLOGY

B – INVERT. ASSEMBLAGE PCA2 (logx+1) PCA1 (log x+1) Dry Flood V. Dry ABSTRACTION BACKGROUND HYDROLOGY

3 – RHEOPHILY TRAITS PCA1 PCA2 Dry Flood V. Dry ABSTRACTION BACKGROUND HYDROLOGY

– INVERT. ASSEMBLAGE PCOA2 (logx+1) PCOA1 (log x+1) 5 Dry Flood V. Dry ABSTRACTION BACKGROUND HYDROLOGY