Trading intensity for space: Aquaculture land sparing through the climate smart shrimp model and field evidence from Central Sulawesi, Indonesia

Title : Trading intensity for space: Aquaculture land sparing through the climate smart shrimp model and field evidence from Central Sulawesi, Indonesia

Abstract:

Shrimp aquaculture is the single largest driver of mangrove loss in Southeast Asia: 48.6% of Indonesian mangrove deforestation between 2000 and 2012 was converted to ponds. The land-sparing framework predicts that intensification on a smaller footprint can release space for ecosystem recovery, yet this prediction remains almost untested in tropical coastal systems. We evaluated the Climate Smart Shrimp (CSS) model, a green-grey protocol that trades controlled intensification for obligatory mangrove restoration within a single land-holding boundary. A five stage protocol was implemented and documented: geospatial site screening against ten weighted criteria; ecosystem characterisation via the Mangrove Health Index, sediment carbon and associated biodiversity; engineering of a wastewater treatment installation hydrologically connected to a restoration block; intensive culture governed by Nature based Solutions principles; and a four dimension Measurement, Reporting and Verification system. Of 58 sites surveyed between 2021 and 2024, only two (3.4%) reached implementation; the binding filters proved to be land tenure legality, partnership arrangements and conservation commitment rather than biophysical suitability. At Lalombi Village, Central Sulawesi, spatial negotiation yielded an allocation of 35% mangrove to 65% ponds and treatment installation across a 10 ha site. The first production cycle from four intensive ponds (1.0 ha water surface; stocking density 170 individuals m?²) yielded 54 t of export-grade shrimp, equivalent to 54 t ha?¹ cycle?¹, 2.7–3.6 times the productivity of conventional intensive ponds and 35% above the design target. The 3.5 ha restoration block showed natural recruitment, with the greatest stem diameter increment in Avicennia officinalis (+1.88 cm), 3.9 times that of Rhizophora apiculata. Aquaculture land sparing is therefore technically achievable, but its conservation multiplier is set by land economics and tenure governance rather than by production capacity.

Keywords: land sparing, ecological intensification, Climate Smart Shrimp, mangrove restoration, green–grey infrastructure, blue carbon

Biography:

Hanggar Prasetio is a coastal conservation practitioner at Konservasi Indonesia, working on the integration of aquaculture and mangrove ecosystem restoration. He leads the site identification and ecosystem assessment components of the Climate Smart Shrimp initiative, including development of the geospatial site-screening protocol and application of the Mangrove Health Index at pilot sites in Central Sulawesi and East Java. He is lead author of the module on site determination and ecosystem condition assessment within Indonesia’s national technical guidance series on sustainable shrimp aquaculture, and has presented CSS implementation results at international forums in New Zealand and Singapore.