We are interested in people’s use of nature to benefit themselves and their households (both directly and indirectly). We are conducting surveys through mobile phones to understand who uses nature’s benefits, how and why they use it, when they use it and where they use it most. We hope to have participants from two locations in Cambodia: Phnom Penh as our urban case study and Preah Vihear as a rural case study. The participants will become our citizen scientists and collect the data via an app, or by receiving phone calls, though the information they provide will be kept strictly confidential (as outlined below). We hope that the data generated will enable us to create a map of the most important places in these regions to the local people, and understand what problems people face in maximising their benefits from nature. The project will take 12 months to complete, with participants receiving small data and talk-time for weekly participation as well as building up credit to ultimately own the phone once the survey is complete (details below). The project will include multiple short tasks each week. Each task will have a set number of points. These points build up and each week you will be given data and talk time corresponding to the number of tasks you have completed that week. It is important to remember that you will not be penalised for failing to complete a task. You can gain the credits later by participating as much as possible in all remaining tasks. Each task completed credit will also gain credit towards owning the phone at the end of the year, when the project is completed. The tasks focus on food, culture, water, wild goods, wellbeing, demographics, income, poverty and natural hazardsDespite being vital for human well-being, ecosystem services (ES) – nature’s contributions to people – are increasingly threatened by human activities (e.g. overexploitation and degradation). The importance of ES is globally recognised. For example, 127 United Nation member states have signed up to the Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services (IPBES; www.ipbes.net). Cambodia (a rapidly developing nation with a high reliance on the agricultural sector but experiencing increasing urbanisation) is among these signatories and has further demonstrated its willingness and commitment to work towards sustainable development by several national-level policies (e.g. National Policy and Strategic Plan on Green Growth). However, the Royal Government of Cambodia has identified a need for more information on how to better manage availability, access, utilisation and stability of ES, arising from a historical bias within ES science (implicitly a social-ecological system linking nature and people) towards ecology at the expense of social science. We use mobile phone surveys administered along the rural-urban spectrum to investigate how people access and use ES, from which ecosystems, how such benefits contribute to people’s well-being, how barriers prevent or reduce these benefits, the sustainability of each of these processes, and by identifying pathways to resilience. We incorporate social science theories into flows and use of ES to transform existing ES models, establishing a step-change in ES research that shifts the focus from natural ecosystems to human beneficiaries. Finally, as well as providing insight into ES access, use and resilience across the rural-urban spectrum, we will validate our technological, smartphone-based approach. Utilising mobile technology to distribute surveys has many potential benefits, including: 1) enabling participants to respond to surveys at a time that suits them , therefore allowing the inclusion of vulnerable groups who can ill afford time away from work to participate; 2) capturing spatially and temporally distinct links between people and nature, which may be unique to the individual and shift over time; and 3) having the potential to be up-scaled, enabling for the inclusion of social science ‘big data’ in ES models. Thus, once properly validated, the smartphone-based method of data collection is inherently scalable and so might enable social science data to be collected over large regions and incorporated into models to address questions about the impacts of ecosystem change on the multidimensional well-being of regional and social-economic groups across scales. In partnership with decision-makers, the advances suggested here could help to ensure ES research contributes to and informs ongoing policy processes (e.g. IPBES) and facilitates the development of ES indicators for monitoring of human well-being and building pathways to resilience in Cambodia and beyond.

MobilES will distribute 480 smartphones to participants: 240 within urban wards of Phnom Penh, and 240 in the rural region of Preah Vihear. The rural sample will be stratified equally across areas that practice i) conventional and ii) wildlife-friendly farming, within the Wildlife-Friendly Ibis Rice Project. All participants will have the opportunity to respond to short qualitative and quantitative survey response tasks on a regular basis, from a daily to monthly timescale (with a maximum of 10 short tasks per week), over a one year period in a ‘microtasks for micropayments’ model (£0.05-0.1 per task, in form of data, sms, or credit toward device ownership), which has shown high retention rates for mobile-phone surveys within south Asia. The microtasks approach via smartphones offers numerous advantages vis-a-vis conventional data collection, such as the ability to capture high-frequency variation (such as shifts in access to ES, or changes in use patterns) without requiring participants to try to recall events of weeks or months in the past. Half the participants (i.e. 120 urban households and 120 rural households, the latter divided equally between conventional and wildlife-friendly farming) will respond to short survey response tasks coded in the Android Open Data Kit (ODK; https://opendatakit.org/) platform. Using ODK, short tasks that can be fit into a moment of downtime enabling a more representative sample than conventional surveys, which can only capture those respondents willing and able to take time away from work to participate - a critical advantage in comparative analysis across strata of income and economic opportunity. Our study design addresses the current challenge associated with this emergent mobile-based mode of data collection - difficulty in validating survey responses - by performing an equivalent telephone survey with the remaining half of our sample. These data contained numerous GPS locations. These have been removed where below the district level as we do not have permission to share these data.