Primary goals

• Understand soil water availability across sloping, degraded tropical landscapes & how this varies across seasons in response to rainfall across wetter/drier periods. A combined approach integrating environmental monitoring data, soil sampling for stable water isotope analysis & drone-based multispectral, thermal & LiDAR data.
• To use this data, alongside species/plant traits data, to inform plantation design/ managements & make better use of available water by targeting appropriate species to site conditions.
• Address:
  a) how long into the dry season can tree seedlings be planted
  b) can strategic planting based in species’ water use maximise tree growth and carbon gain?

Key outcomes*

*Data analysis (isotope-based, drone-based, and monitoring data) is ongoing.

1. Nine hill sites have been instrumented with weather stations and soil moisture datalogging equipment to monitor soil water availability across hillslopes (top to bottom), across soil parent materials (limestone/volcanic derived soils) across 3 islands in the rural tropical Eastern Visayas region. These sites were planted with either single-species or mixed-species designs incorporating slow and fast-growing tree species. A paired sensor-seedling site was also established to assess variations in soil water content and understand their relationship with the growth of seedlings of four of the most commonly-planted species in the project.
2. Three key data collection campaigns have been carried out: in the mid-wet season, at the end of the wet season and in the dry season, in addition to regular rainwater sampling for stable water isotope analysis. A paired destructive soil sampling and drone-based data collection was conducted across one limestone and one basalt hill site at the end of the wet season.

Progress

This project commenced in June 2024. Data analysis (isotope-based, drone-based, and monitoring data) is ongoing. 

Lead researchers

• Alexandra Catling
• Adriana Vega Grau
• Calum McRae
• Nick Kokkas

Project partners

• Project Tarsier
• Shell

Sustainable Development Goals

This project works towards these UN Sustainable Development Goals:

• SDG 13: Climate Action
• SDG 15: Life on Land