Assessing the potential of smallholder teak for resilient tropical forest landscapes

Tue, 06 Oct 2026 00:00:00 +0000

Teak (Tectona grandis) is one of the world’s most valuable tropical hardwoods, with sustained demand for furniture, construction and high-value wood products. Global planted teak is estimated at about 4.85 million ha, concentrated mainly in Asia but also established across Latin America and Africa. Smallholders manage approximately one quarter of the world’s planted teak—around 1.2 million ha—and ownership is becoming increasingly private and decentralized. Their significance is particularly visible where teak is grown on farms and outside state forests. In Java, for example, many farm households integrate teak into mixed tree-based agroforestry systems supplying domestic wood industries. Such systems can make a substantial contribution to rural livelihoods; in the Indonesian cases examined by some experts, agricultural and timber crops together accounted for approximately 40% of household income. In Myanmar, home to the world’s largest natural teak forests, degradation of natural teak resources has reinforced the importance of well-managed plantations, including stronger support for private teak growers. Smallholders should therefore be viewed as a structural component of the teak economy. Smallholder teak differs fundamentally from large-scale industrial plantation forestry. Trees are often integrated with crops and other species, retained as household assets, and harvested selectively when cash is needed for education, housing, health care or other major expenditures. Teak can therefore function simultaneously as timber, savings, and risk management. Research in Indonesia and Lao PDR shows that smallholder tree growing responds not only to biological productivity but also to tenure security, market demand, regulation, finance and practical silvicultural support. This perspective shifts the question from how to expand teak plantations to how to realize the potential of smallholder teak within resilient tropical forest landscapes. That potential should be assessed through three linked dimensions: economic viability for households, social and institutional viability for producer participation, and environmental viability at farm and landscape scales. The central proposition of this editorial is that environmental benefits are more likely to endure when smallholders can obtain reasonable returns, manage production risks and participate fairly in accessible markets. The analysis draws primarily on the Global Teak Resources and Market Assessment 2022, established research on smallholder teak in Indonesia and Lao PDR, and recent implementation experience from the ITTO–BMLEH Teak Project. The Proceedings of the 5th World Teak Conference (WTC), held in Kochi, Kerala, India, on 17–20 September 2025, are used selectively to reflect recent developments in teak investment, markets, genetics, management and landscape resilience.

Analysis of water-regulating ecosystem services in the Upper Ciliwung Watershed from 2015 to 2025 based on vegetation index, morphometric characteristics, and soil properties

Miesriany Hidiya, Boedi Tjahjono, Dolly Priatna — Tue, 06 Oct 2026 00:00:00 +0000

The Upper Ciliwung Watershed plays an important role in regulating the hydrological system of downstream areas, particularly Jakarta, which is highly prone to flooding. Population growth within the Greater Jakarta metropolitan area and land conversion in the Puncak region have reduced the watershed’s capacity to provide water-regulating ecosystem services. This study aims to (1) assess and map water-regulating ecosystem services in the Upper Ciliwung Watershed in 2015 and 2025 and (2) evaluate their dynamics and formulate management recommendations for flood mitigation. The assessment was conducted using a Multi-Criteria Evaluation (MCE) method based on four parameters: slope, Topographic Wetness Index (TWI), Normalized Difference Vegetation Index (NDVI), and soil depth. The study used 30 m resolution SRTM data, Landsat 8/9 imagery acquired in 2015 and 2025, and a 1:50,000-scale soil map produced by the Indonesian Center for Agricultural Land Resources Research and Development. Spatial analysis was performed using ArcGIS Desktop 10.8, while the reclassified values were categorized using the Natural Breaks method. The results indicate that water-regulating ecosystem services in the Upper Ciliwung Watershed degraded over the ten-year period. The area classified as low increased from 12,493.90 ha (81.94%) in 2015 to 13,630.20 ha (89.39%) in 2025, while the moderate class decreased from 2,644.38 ha to 1,598.94 ha, and the high class declined from 109.17 ha to 18.31 ha. This degradation indicates a decline in the watershed’s capacity to retain and infiltrate rainfall, thereby increasing flood risk in downstream areas. The recommended management measures include revegetation of open areas, implementation of agroforestry practices on agricultural land, stricter spatial planning controls in settlement areas of the Puncak region, and strengthened interjurisdictional coordination based on the one river, one plan approach.

Indonesian Journal of Applied Environmental Studies

Assessing the potential of smallholder teak for resilient tropical forest landscapes

Analysis of water-regulating ecosystem services in the Upper Ciliwung Watershed from 2015 to 2025 based on vegetation index, morphometric characteristics, and soil properties