Imitating Natural Ecosystems through Successional Agroforestry for the Regeneration of Degraded Lands A Case Study of Smallholder Agriculture in Northeastern Brazil Jennifer Schulz - Jorge Aubad

Overview 1. Land use and degradation worldwide 2. Objective and Strategy 3. Cultivation concept 4. Case studies in Northeastern Brazil 5. Conclusions

Land use and degradation globally 3 Degradation of land ~ Mio. Hektar / Year (UNEP 2002) 4 Increase in cultivated area ~ 3,8- 5 Mio Hektar / Year (FAO 2003) 1 Population (UNO 2004) 2 Area of agriculture (Wood et al. 2001) % continental surface World population in billion people

Objective and Strategy Objective: Regeneration of degraded agricultural land and environmental functions and services on areas of land use Landscape scale: Environmental functions need to be gradually replaced on the area of agricultural land use Strategy for land use: Approximation of agricultural uses to natural ecosystems  Imitation of the functional principles of local natural ecosystems

Guiding image: « natural, intact ecosystems » Imitation of structure and function of ecosystems

Guiding image: « natural, intact ecosystems » Imitation of structure and function of ecosystems Perennialism and Diversity Vegetation strategies: Optimal use of locally limited ressources (solar energy, water, nutrients) Succession: 1. Maximum accumulation of biomass 2. Coupling / Association of functional different, mostly complementary species  Short cycles of water, energy and nutrients, reduction of losses

Concept „Successional Agroforestry“ Font: Götsch, 1997

Imitation of successional trajectories of the local ecosystem Acceleration of natural processes through systematic interventions:  dense seeding of fast growing plants (first successional step includes mainly pioneer colonizers e.g. Leguminosae)  systematic trimming  production of mulch for fast accumulation of organic material  systematic creation of gaps through cuttings for the plantation of use-plants of a higher successional level Concept „Successional Agroforestry“

Selection of a mixture of locally endemic and culture species according to 2 criteria: Stratum + Lifetime Goals: increasing coupling of different functional types Concept „Successional Agroforestry“ Font: adapted from Milz, 2004

Case studies on degraded areas in Northeastern Brazil  1/3 of population of brazil  ~ 88% smallholder farmers  Degradation of soils: ca. 50%  Desertification ca km 2  strong rural- urban migration Font: EMBRAPA, 2000

Project A: humid coastal zone Precipitation: mm/a Soil: sandy loam, low fertility Size: 1 hectar Project start: 1994

Initial situation

after 10 years

Leguminosa trees trimmed Fresh layer of leeves (ground)

Neighbours´ field Successional system Development of an organic soil horizon

Regeneration of a degraded unproductive site  Provision food, construction- and firewood  High level of subsistency for 4 persons on 1 hectar and increased income due to direct marketing of organic products including: Banana, mango, jackfruit, papaya, coffee, avocado, cocoa, orange, lime, cupuaçu, açai, corn, rice, beans, cassava Results

Project B: semiarid zone Prec.: ca. 550 mm/a pot. ETP: 2000 mm/a Dry period: 7-9 Month, in periodical dry years 18 months Size: 1500 collaborating farmers, 1000 m² experimental area Project start: 1999/2000

Fotos: Instituto de Permacultura da Bahia 2. cultivation year end of rainy season 1. cultivation year 2. month of rainy season Initiation of the successional system in the rainy season

3. cultivation year end of rainy season 3. cultivation year beginning of dry season Fotos: Instituto de Permacultura da Bahia

Productivity Province Cafarnaum Medium production kg/ ha Production increase through successional AF Rizinus monoculture Regional Ø 800 kg/ha factor 1 Rizinus successional system 1497,5~ factor 1,9 Productivity * per ha success. system ~ factor 4 * At least 5 additional crops in production

Participation of 1500 farmer families in 5 communities facilitated by a payment of 18 US$ per month during 4 years  from the 4th year on - complete subsistency possible Regeneration of degraded sites and increase of productivity without irrigation and external inputs Decrease of risk for harvest loss through diversity of perennial and anual plants  higher resilience  Provision of environmental goods as an existential basis  Reduction of the strong rural-urban migrations Project results

farmers adopt SAF rather in drier zones and conditions of stronger degradation Critical for success are: Capacity building in two directions: Local knowledge in exchange with external expert impulse - Training of multiplicators  Organisation of local knowledge exchange and the creation of farmers associations  Development of local market chains for organic products Comparison & Critical aspects:

Concept „Successional Agroforestry“ is successful Conclusions:  Regeneration of an existential basis, local ecological knowledge and farmers empowerment  improvement of the local livelihood  Stabilization and regeneration of environmental regulation functions at local scale  Potential for regeneration of regulation functions on critical areas within the landscape

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