Early Results and Guidance from a Coastal Habitat Restoration Project Twenty Years after the 1991 Gulf War Oil Spill

Transcription

1 Early Results and Guidance from a Coastal Habitat Restoration Project Twenty Years after the 1991 Gulf War Oil Spill Christopher D. Cormack Jason A. Hale, Owen Langman, Thomas G. Minter, Michael J. Risk, Linos Cotsapas, Jacqueline Michel

2 Overview Background Gulf Spill Principles - UNCC Restoration Program Actions - What are we doing, and why? Channelization Tilling Planting Guidance Lessons learned

3 Oil Spill 1991 Gulf War 10 M barrels 800 km KSA shoreline

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6 Deepwater Horizon

7 The Consequences 20 years later: Little natural recovery Heavy oil loading (physical + toxicity effects) Low energy setting Deep penetration into burrows Physical alterations to habitat (disrupted hydrology by algal mats)

8 Heavily Impacted Marsh Healthy Marsh How do we go from..to..

9 Guiding Principles Adhering to Decision 258 and F4 panel principles; remediation activities aim to: avoid techniques that pose unacceptable risks result in more positive than negative results facilitate natural recovery to the extent possible rely on proven techniques utilize adaptive management be cost effective consider short- and long-term effects and landscape connectivity

10 Approach Target Ecological Restoration Methods must include: Adaptively managed Understand and characterize conditions and site Identify stressors Design appropriate remediation activities Test and monitor effects of remediation activities

11 Adaptive Management Increasing Knowledge Demonstration Contracts Large-scale Remediation Contracts Pilot Projects Small-scale Studies Increasing Scale and Complexity

12 Adaptive Management Increasing Knowledge Demonstration Contracts Large-scale Remediation Contracts Pilot Projects Small-scale Studies Increasing Scale and Complexity

13 Progression of Stress Part 1: Oil

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15 Progression of Stress Part 2: Algal Mat

16 Progression of Stress Part 2: Algal Mat What s wrong with this picture? Algal mat as a barrier

17 Progression of Stress Part 3: Hydrology

18 Progression of Stress Part 3: Hydrology What s wrong with this picture?

19 Oil Algal Mat Hydrology

20 How to Restore Salt Marsh Habitat?

21 Choosing Remediation Activities EXCAVATE - Refresh (existing) and/or excavate (new) tidal channels TILL Remove algal mats/de-compact and aerate substrate in marsh and tidal flat habitats PLANT - Transplantation of mangroves/halophytes to rapidly increase the populations

22 Channel Excavation What s wrong with this picture? better?

23 CRC1 Colonization Two months post excavation South Channel North Channel Nasima Snails Amphipods

24 CRC1 Colonization Three months post excavation South Channel North Channel Nasima Snails Amphipods

25 CRC1 Colonization Four months post excavation South Channel North Channel Nasima Snails Amphipods

26 CRC1 Colonization Five months post excavation South Channel North Channel Nasima Snails Amphipods

27 CRC1 Colonization Six months post excavation South Channel North Channel Nasima Snails Amphipods

28 CRC1 Colonization Seven months post excavation South Channel North Channel Nasima Snails Amphipods

29 CRC1 Colonization Eight months post excavation South Channel North Channel Nasima Snails Amphipods

30 CRC1 Colonization Nine months post excavation South Channel North Channel Nasima Snails Amphipods

31 CRC1 Colonization Ten months post excavation South Channel North Channel Nasima Snails Amphipods

32 CRC1 Colonization Eleven months post excavation South Channel North Channel Nasima Snails Amphipods

33 CRC1 Colonization Twelve months post excavation South Channel North Channel Nasima Snails Amphipods

34 Excavation of Tidal Channels

35 10-May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr-2012 Number of Burrows present in channel along 10 m transect Monitoring Results To Date Low Elevation Mid Elevation High Elevation

36 Natural Channel Development Aug 1

37 Natural Channel Development Oct 31

38 Natural Channel Development Dec 12

39 Natural Channel Development Dec 12

40 Natural Channel Development Dec 12

41 Tilling Three alternative marsh surface treatments: Tilling Algal mat removal Algal mat removal followed by tilling Treatment directly adjacent to channel excavation in 5 x 5 m plots

42 CRC1 Alternative Treatment Plots - 0 Months South Channel North Channel - Till - Remove Algal Mat - Remove Mat and Till

43 CRC1 Alternative Treatment Plots 3 Months South Channel North Channel - Till - Remove Algal Mat - Remove Mat and Till - Colonized by Nasima

44 CRC1 Alternative Treatment Plots 6 Months South Channel North Channel - Till - Remove Algal Mat - Remove Mat and Till - Colonized by Nasima

45 CRC1 Alternative Treatment Plots 9 Months South Channel North Channel - Till - Remove Algal Mat - Remove Mat and Till - Colonized by Nasima

46 CRC1 Alternative Treatment Plots 15 Months South Channel North Channel - Till - Remove Algal Mat - Remove Mat and Till - Colonized by Nasima

47 Jan-11 Feb-11 Apr-11 Jun-11 Jul-11 Sep-11 Nov-11 Dec-11 Feb-12 Apr-12 May-12 Jul-12 Average number of Nasima burrows per m 2 +/- SE Tilling/Algal Mat Removal 30.0 Algal mat Removal Algal mat Removal and Tilling Tilling Only 15.0 Control - No Surface Treatment

48 Planting

49 Planting Mangroves Avicennia marina Perennial Halophytes Halocnemum strobilaceum Arthrocnemum macrostachyum

50 Mangroves Observable changes (same plant) after 2 months after 6 months after 1 year

51 Mangroves Observations: Majority of previously surviving plants continue to grow Overall plant height has not increased, however, branch density and leaf count is increasing

52 1/22/2010 5/2/2010 8/10/ /18/2010 2/26/2011 6/6/2011 9/14/ /23/2011 Average number of healthy leaves per plant Monitoring Results To Date C1 C2 C3 80 Natural B channel

53 Mangroves Transplanting mangroves in oiled sediments can be successful Poor survival in areas lacking drainage, having high oil concentration, and high algal mat cover Highest survival on banks of newly excavated channels. Linkage between excavation and planting

54 Adaptive Restoration Process Increasing Knowledge Small studies Meters Pilot Projects Demonstration Contracts Increasing Scale Large Scale Remediation Contracts Hectares

55 Lessons Learned Rapid increases in colonization can occur in areas of remediation until balanced state is achieved Abundance of organisms colonizing areas may follow seasonal trends Channels not expected to fill or slump Planting success is species dependant

56 Guidance Lessons Learned Channel Excavation Efficient method in low energy environment to increase tidal flushing and promote recolonization.

57 Guidance Lessons Learned Channel Excavation Efficient method in low energy environment to increase tidal flushing and promote recolonization. Channels will continue to be the primary method of remediation of the salt marsh habitats

58 Guidance Lessons Learned Tilling Effective at reducing oil residues and de-compact areas covered by barrier increasing potential for recolonization

59 Guidance Lessons Learned Tilling Effective at reducing oil residues and de-compact areas covered by barrier increasing potential for recolonization Increased areas of tilling have been incorporated into future contracts

60 Guidance Lessons Learned Planting Recommended for species that are slow to recruit and grow but also able to survive and establish following transplanting

61 Guidance Lessons Learned Planting Recommended for species that are slow to recruit and grow but also able to survive and establish following transplanting Mangroves are to be included along the banks of the channels in all future contracts Other halophytes remain limited to small scale/demonstration tests until successful methods can be determined

62 Adaptive Restoration Process Increasing Knowledge Small studies Meters Pilot Projects Demonstration Contracts Increasing Scale Large Scale Remediation Contracts Hectares

63 Adaptive Restoration Process Other Remediation Projects Increasing Knowledge Small studies Meters Pilot Projects Demonstration Contracts Increasing Scale Hectares

64 Thank You Christopher Cormack Pandion Technology