Rubber and oil palm are clearly the two most important income sources for the population in rural Jambi. This holds true for farm households and also for non-farm households that often find employment on rubber and oil palm plantations (Euler et al. 2016, Bou Dib et al. 2018a). While rubber has been a traditional crop in the region for more than 100 years, oil palm was only introduced in the 1980s and has expanded rapidly since then (Gatto et al. 2017). Both crops are grown on large company plantations as well as by smallholder farmers. Smallholder oil palm cultivation in Jambi started as a result of the transmigration program of the Indonesian government in the late 1980s. This program moved people who had no land from densely populated areas to less populous areas of the country. Initially, smallholders produced oil palm under contract with large companies. However, nowadays most of the smallholder oil palm cultivation takes place independently, without company contracts. It is estimated that smallholders currently produce around 40% of the total palm oil in Indonesia (Byerlee et al. 2017, Euler et al. 2017).
Comparing the economic effects of rubber and oil palm in the smallholder sector, rubber led to higher profits per unit area than oil palm when a lot of family labour is used (Fig. 1E). However, rubber was much more labour-intensive than oil palm, so that the return per unit labour cost was higher in oil palm cultivation (Euler et al. 2017; Fig. 1F). Our representative data from smallholder farm households in Jambi showed that oil palm was more profitable than rubber and that households that cultivated oil palm had higher incomes and enjoyed higher living standards than households that had not adopted the oil palm crop (Krishna et al. 2017). These economic gains from oil palm cultivation were also the main reason for the rapid expansion of the oil palm area in the small farm sector (Kubitza et al. 2018).
Rural non-farm households benefited from the shift from forest to monoculture rubber and oil palm plantations through additional employment opportunities (Bou Dib et al. 2018a). The associated gains in employment incomes were important from a social perspective, because non-farm households typically belong to the poorest population segments in rural Jambi. Our data showed that poverty rates are close to 20% in villages where little rubber and oil palm were cultivated. In villages where rubber was the dominant land-use type, the average poverty rate was around 14%; whereas in villages where oil palm was the dominant land-use type, the poverty rate was only around 8% (Bou Dib et al. 2018b).
Our qualitative case studies showed that the expansion of oil palm plantations and the simultaneous expansion of protected areas have fostered tensions over land (Hein et al. 2015; Hein 2018, Kunz et al. 2017). The research results demonstrated that land tenure regulations are complex. We found that regulations, which were added over time by various political authorities at different levels of governance, to customary laws created a situation of legal pluralism (Kunz et al. 2017). Recent territorial conflicts mirror the contradictory interests of different governmental organisations, transnational actors, and local people, influenced by conservation-oriented and development-oriented groups of the society (Hein et al. 2018, Hein 2019). This also resulted in smallholders being deprived of access to land due to the allocation of concession areas for development or conservation purposes by the state, often lacking secure title deeds for sustaining their livelihoods (Beckert 2017).


Figure 1 Multiple aggregate ecosystem functions and their indicators. Yield/harvested biomass (A), carbon stocks (B), naturalness (C), observed local species richness (D), gross margin per hectare (E), and gross margin per hour labor (F). Indicators for naturalness (C) are: proportion forest species among bird communities, proportion indigenous tree species, proportion common weed species present. Indicators for biodiversity/species richness (D) are: number of species/operational taxonomic unit of trees, understory plants, birds, litter invertebrates, termites, ants, testate amoebae, archaea and bacteria recorded per plot. Variables in a-d were standardised to allow joint plotting. Details are given in Clough et al. 2016.