Ecological restoration of drylands: practice, outcomes and future perspectives

Transcription

1 Ecological restoration of drylands: practice, outcomes and future perspectives Alice Nunes & Working Group 3 COST Action ES1104 Alice Nunes (amanunes@fc.ul.pt) Cristina Branquinho (cmbranquinho@fc.ul.pt)

2 Ecosystem functioning (biomass, nutrient cycling, etc.) Ecological restoration: the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed (SER) Reclamation Ecological restoration Reference Ecosystem Rehabilitation Attributes of the restored ecosystem Species diversity (similar to the reference ecosystem) Community structure (similar to the reference ecosystem) Presence of functional groups Degraded Ecosystem Natural processes (sucession) Ecosystem structure and diversity (species number, habitat complexity, etc.) Presence of native species Biotic flows with surrounding areas Self-sustainability Resilience (

3 Drylands: cover about 41% of Earth s land surface are inhabited by 38% of the human population Millennium Ecosystem Assessment (2005) Ecosystems and Human Well-Being: Desertification Synthesis (World Resources Institute, Washington, DC).

4 Aim: to gauge the range of restoration projects that have been implemented in dryland areas, to establish current knowledge of best practice for dryland ecological restoration Discussion among the WG3 concerning the survey target areas, format, structure and questions Target: dryland areas in Europe and also in other parts of the world Format: on-line survey (or by other means whenever more convenient) Structure and questions: divided into parts A and B

5 Part A: information about the contributing expert and the restoration project area (10) Part B: detailed information about restoration projects I. Context and motivation (7) II. Planning, practice and maintenance (9) III. Criteria for plant species selection (14) IV. Monitoring and outcome (7) V. Costs and benefits (6)

6 : answers to part A Total of 148 answers, 81% drylands

7 : answers to part A Total of 77 answers (52%) in Europe and surrounding area, from which 74% drylands

8 : answers to part A Europe 77 Armenia 2 Azerbaijan 1 Belgium 1 Bulgary 3 England 1 Georgia 2 Germany 2 Greece 4 Iceland 1 Israel 6 Italy 3 Many 3 Portugal 12 Serbia 2 Spain 24 Switzerland 1 Turkey 8 Netherlands 1 Answers from 46 countries Africa 28 Algeria 4 Botswana 2 Burkina Faso 1 Egypt 2 Ethiopia 1 Ghana 1 Kenya 2 Many 1 Morocco 2 Namibia 1 Niger 1 Rwanda 1 Senegal 1 Tanzania 1 Togo 1 Tunisia 5 Uganda 1 Asia 28 China 5 India 8 Iran 7 Jordan 1 Lebanon 1 Nepal 1 Pakistan 2 Palestine region 1 United Arab Emirates 1 Uzbekistan 1 America 7 Brasil 5 United States 2 Australia 2 Australia 2

9 : answers to part A Ecohydrologist Ecologist Forest_engineer/agronomist Who answered? Geographer/Geomorphologist Project_manager/coordinator Social_sciences Soil_engineer/scientist Governamental instituition Where from? Private University/Research institute

10 : answers to part B (more detailed info) Total of 59 answers, 78% in drylands, 59% in Europe and surrounding area

11 B-I. Context and motivation WP3 survey on ecological restoration of drylands Habitat type Forest/Woodland Evergreen shrubland Perennial grassland Annual grassland Xeric shrubland Savanna Farmland/agricultural Dunes Riparian

12 B-I. Context and motivation Overgrazing Deforestation/Fuel collection Natural (drought, etc.) Intensive agriculture Infrastructure development (roads, dams, etc.) Industry activities/mining Fire Invasive species Extensive agriculture Main degradation causes

13 B-I. Context and motivation Government iniciative General legislation Public pressure Enterprise/private initiative Protected areas legislation Scientific research Public health NGOs Restoration motivation

14 B-I. Context and motivation Soil erosion People livelihood Ecosystem services Biodiversity Landscape impact Conservation Invasive species Pollution Floods Sustainable management Dune stabilization Scientific research Restoration aims

15 B-II. Planning, practice and maintenance Original soil disturbed (erosion) Original soil undisturbed Added local topsoil Treated soil (e.g. fertilized, organic amendment) Added non-local topsoil Added unstructured substrate (e.g. spoil WP3 survey on ecological restoration of drylands Soil used Planting plants grown in nursery Seeding/sowing Transplantation from local area Inocculation/transpl. biological soil crusts Hydroseeding Grazing exclusion Topsoil transfer Revegetation techniques

16 B-III. Criteria for plant species selection Drought tolerance Erosion control Nativeness Economic value (e.g. timber, bio-oil) Social acceptance Aesthetic value Salinity tolerance Shading/microclimatic amelioration Biotic interaction Fire High/low ph tolerance Dispersion ability Soil nutrients Fast growth Biodiversity Carbonate tolerance Plant selection purpose

17 B-III. Criteria for plant species selection Plantation Only native Both Only non-native None native non-native (seedlings) Seeding/Sowing Only native Both Only non-native None native non-native (seeds)

18 B-III. Criteria for plant species selection Reasons for the use of non-native species Growth rate Comercial availability Price Timber Nurse, to be removed Knoledge growing requirements Aesthetic Biodiversity Resistance

19 B-III. Criteria for plant species selection Nr woody species Nr herbaceous species >15 < > % compared to the reference/non-disturbed ecosystem? <20% 20-50% 51-80% >80% <10% 10-20% 21-50% 51-80% >80%

20 B-IV. Monitoring and outcome Restoration Results As expected Partially unexpected Unexpected results High mortality Low biodiversity Native species dominance Erosion Fast recovery Low cover Low social involvement Low recruitment Low mortality Non-native species dominance

21 B-IV. Monitoring and outcome Drought/harsh climate Soil degradation/low quality Erosion Not enough time passed Herbivory Fire Invasive species Social reluctance Fragmentation Soil contamination Pests Lack of maintenance Excessive irrigation Causes for unexpected results

22 B-IV. Monitoring and outcome never <1year 1 year 2-5years 6-10years year >20 years Success evaluation Partially successful Successful Unsuccessful

23 B-IV. Monitoring and outcome Plant cover Plant species number Plant diversity Plant mortality/vitality Soil N SOM Soil erosion measures Biomass production Soil physical analysis Plant functional diversity Multi-taxa Litter cover/decomposition Animal species abundance Animal species number C sequestration Soil microbial activity Indicator species Aesthetic Social aproval Eco-turism Soil ph WP3 survey on ecological restoration of drylands How was the success evaluated? Attempt to quantify ES? No Yes

24 Restoration cost ( /ha) B-V. Costs and benefits WP3 survey on ecological restoration of drylands Min: 2 /ha Mean: 2110 /ha Máx outliers: and /ha Restoration Cost Appropriate, considering future benefits Low, considering benefits Appropriate, considering current benefits High, considering benefits

25 Some preliminary conclusions Main restoration aims: protect soil from erosion, improve people livelihood, improve ecosystem services (ES), increase biodiversity Most projects use original soil or add local topsoil; revegetation mainly through planting and seeding and to a lesser extent local transplantation and BSC Mostly native species are used; non-native species are used mainly due to a higher comercial availability and lower price Restoration success is evaluated in short to medium term, and firstly based on plant and soil data High plant mortality and low biodiversity are the main limitations to restoration success, attributed to drought Althoug improving ES is a major restoration aim, few attemps are maid to quantify them

26 Work in progress Which techniques are associated with higher restoration success? Under different aridity levels? Protected vs. unprotected areas? Discuss the evaluation of ecosystem services in restoration Expected output: a peer-reviewed paper

27 Thank you for your attention Alice Nunes Cristina Branquinho Acknowledgments: Authors: Alice Nunes Teresa Mexia Graça Oliveira Otília Correia Benz Kotzen Sarah Milliken Alejandro Valdecantos Ruediger Prasse Eleni Abraham Apostolos Kyriazopoulos Edoardo Costantini Ayman Salah Abdel Rahman Al-Tawaha Cristoph Kuells Gudrun Schwilch & Cristina Branquinho COST Action ES1104 Arid lands restoration and combat of desertification: setting up a drylands and desert restoration hub SFRH/BD/51407/2011)