El Nino x forest resilience

The widespread and rapid logging of tropical forests may mean they are unable to withstand climate shocks such as El Niño events.

Logging slashes the abundance of invertebrates like ants and earthworms, but vertebrates can take up their roles in the ecosystem. Invertebrates perform essential functions for the smooth running of the ecosystems in tropical forests. For example, creatures such as termites and millipedes help dead leaves decompose and release their nutrients back into the soil, and carnivorous ants and spiders act as predators of herbivorous invertebrates that would otherwise munch through all the foliage.

Nearly a half of all tropical rainforests worldwide have been logged, and this often causes heavy changes to the number and type of invertebrates, with many species being lost from the ecosystem. But when invertebrate diversity declines, their vital functions can be carried out by other members of the ecosystem, including vertebrates including rodents, birds and bats. Because of this, rainforest ecosystems have a remarkable resilience to change.

However, although the ecosystem can continue to function with vertebrates taking more of a leading role, the situation leaves rainforests vulnerable: the forest will keep maintaining itself, but it will be much more susceptible to further change. Relying on vertebrates is probably a bad tactic - they are less diverse and vulnerable to new challenges.

One such new challenge is the drought that accompanies El Niño events. There is already evidence that El Niño events can disrupt the resilience of ecosystem processes to logging disturbance. For example, the number of seedlings germinate and establish in logged forest during an El Niño year is just one-sixth of the number that establish in primary forest during the same year. What's more, those seedlings then die almost twice as fast in a logged forest during El Niño than they do in primary forest.

This project will examine the resilience of tropical forest ecosystem processes to an El Niño event, asking specifically whether El Niño reduces the resilience of ecosystem processes to logging disturbance that otherwise keeps those forests functioning between El Niño events. I will do this by comparing historical data collected in both primary and logged forests with new data that will be collected during the 2016 El Niño event. My goal is to generate a broad picture of the interactive impacts of El Niño and logging on the forest ecosystem as a whole, for which I will necessarily sacrifice detailed understanding of any one ecosystem process.

Instead, I will be looking at a very broad range of data types and measurements of how the forest works and what species are doing the jobs. The data will record the rate at which 15 ecosystem processes operate in primary and logged forest habitats, encompassing metrics of tree dynamics, interactions across plant and animal communities and nutrient recycling processes. These data will be compared to records on the abundance and biomass of 26 functional groups nested within seven plant and animal communities, covering all major trophic groups including early and late successional tree species, and vertebrate and invertebrate herbivores, predators, scavengers and omnivores.

The beneficiaries of this research fall into four broad groupings, the first three of which are interrelated and stand to gain similar benefits.

1. Public sector organisations, particularly the Sabah Forestry Department (SFD): SFD is responsible for the sustainable management of Sabah's extensive forest estate, issuing all logging concessions and permits for conversion of logged forest estates into plantation. I work closely with SFD on the SAFE Project and SAFE has been strongly supported by Datuk Sam Mannan, the SFD Director. I will be able to feed results and management recommendations to Datuk Mannan and the relevant management committees with the potential to directly influence SFD policies and requirements for new logging and land use clearance operations.

2. Private sector, specifically oil palm and forestry companies: This study is based at the SAFE Project, a collaboration between academia (led by myself) and the oil palm industry (particularly Sime Darby, the primary funder of SAFE). This research will help quantify the resilience of logged forest patches that are retained within oil palm plantations - which have almost inevitably been logged - to extreme climatic events such as El Niño. It has considerable relevance to the design of new plantations in which retaining High Carbon Stock forests is rapidly becoming an important consideration. Data collected in this project will also have relevance to designing best-practice Reduced Impact Logging techniques and thresholds of logging intensity beyond which forests lose resilience, and will be of interest to companies such as Usahawan Borneo, the logging company contracted to work at the SAFE Project. I will be able to feed results to the Board of Sime Darby and to the CEO of Usahawan Borneo, along with any recommendations about best practice.

3. Third sector organisations, particularly conservation NGOs and industry groupings such as the Round Table for Sustainable Palm Oil (RSPO) and the High Carbon Stock (HCS) consortium: I will work closely with the South East Asia Rainforest Research Partnership (SEARRP) that supports scientific research in Sabah, including the SAFE Project, and that has two dedicated Impact Managers whose role is to translate science into policy. SEARRP holds a seat on the RSPO Biodiversity Committee and is well placed to feed results from this proposal into this high-level grouping of industry and conservation NGOs. My results will have important implications for the definition of 'sustainable' landscapes and plantations that form a central component of oil palm certification schemes operated by RSPO and the scheme currently in development by HCS. I sit on the Science Advisory Committee for HCS and will be able to feed results directly into their decision making processes.
4. Academic community: The researcher community will benefit from the new knowledge and extensive datasets generated by the project and the scientific advancement on a topic of global importance. All data generated in this research will be made available via the NERC Environmental Information Data Centre and the SAFE Project online database. My proposal will present the broadest assessment of forest ecosystem resilience to El Niño that has ever been conducted, providing a unique opportunity to examine the multitude of linkages within and among functional groups and ecosystem processes.