Sustainable resource use or imminent collapse - project description

Sustainable resource use or imminent collapse?

Climate, livelihoods and production

in the Southwest Pacific

CLIP

Research project part of the

 Galathea 3 Scientific Expedition

Danish partners:

Institute of Geography, University of Copenhagen (IGUC), Denmark

Danish Meteorological Institute (DMI), Denmark

International partners

University of the South Pacific, Solomon Islands and Fiji Campuses

University of Cambridge, United Kingdom

Australian National University, Australia

East-West Center, Hawaii, USA

1.      Introduction – objectives and research questions

This project addresses the sustainability or collapse of production systems, which are the key to understanding the survival of the populations and civilizations of the Southwest (SW) Pacific islands in the past, present and future. In the past, the causes of collapse have been either external and/or internal; Easter Island is often men-tioned as a classical case of a collapse resulting from the workings of internal forces (1), while other islands are reported to have been deserted due to climate change. Today, the SW-Pacific islands face challenges related to ‘classical’ problems of sustaining growing populations, as well as ‘modern’ problems of globalisation and global change. In the future these challenges will become even more pronounced and islands are likely to be extremely vulnerable to changes in climate, affecting the agricultural potential, and in sea level, affecting the land resources available, especially in the case of atolls.

In this context, this interdisciplinary project will address two closely linked questions:

-          Firstly, have the changes over the last 30-50 years in subsistence production systems and livelihoods on the islands improved or worsened the prospects for sustainable development, and what have been the main drivers of these changes?

-          Secondly, how do the predicted changes in climate and sea level and economic globalisation processes affect production and livelihoods in small island communities, and to what extent is the quantification of relationships between these parameters possible?

The results of the project are believed to have considerable general applicability and popular appeal; understan-ding the persistence or collapse of civilizations living in confined spaces within well-defined resource con-straints provides a model for conceptualising the in principle similar, but far more complex, problems of survi-val on Planet Earth. Similarly, the handling of the consequences of global climate change, which poses a serious threat to populations on these islands, constitutes a more widely relevant test of the balancing of global solida-rity against economic/utilitarian rationalism.

2.      Subsistence and global change in the SW Pacific

This study will focus on three islands which have all been subject to earlier studies of agricultural systems and land use: Christiansen (2) provided a classic analysis of subsistence systems on Bellona, Bayliss-Smith gave detailed accounts of survival and development on Ontong Java (3-6) as did Firth (7) for Tikopia. While differing in many respects, these studies all provide a baseline against which the current situation can be assessed and form the basis for analysing the changes over the past 30-50 years. Before addressing the specific situation of these islands, however, we will outline the dynamics of subsistence systems and the impact of global change in the SW Pacific.

Subsistence production, predominantly agriculture supplemented by fishing, gathering and hunting, has tradi-tionally been the main livelihood strategy for most of the small island communities in the SW Pacific as repor-ted in the studies mentioned above. It is regulated by local land and sea tenure systems (8-11), which are essen-tial institutions that enable or constrain natural resource management practices and thus are central to understan-ding change and resilience of these (12). Fishing and forest products provide important additions to the diet (13,14), but agriculture remains one of the most important economic activities (15). The traditional agriculture is based on taro, yams and sweet potatoes in garden plots, often using shifting cultivation (2,7), but in many islands this is being supplemented or replaced by cash crops (2,16). Cash income earned from the sale of copra and other sources has been used to purchase foodstuffs for the latter part of the 20^th century, which has increa-singly substituted local subsistence crops in the diet (17). A study from Ontong Java reports that the share of imported food in the diet doubled from 25% in 1970 to 51% in 1986, and increased reliance on modern boat technology caused per capita consumption of outboard engine fuel to increase 100-fold in the same period (18).

Such dramatic changes reflect increasingly complex livelihoods partly caused by high annual population growth rates (approximately 2.7-3.0% between 1999 and 2003 (19) and increased contact with both regional and global economies. The latter has in some places lead to what is termed ‘economic crowding’ (20) as tourism, and asso-ciated resource use, has become another potential source of income for the island communities and has created increased pressure on natural resources (9,21-23). Moreover, circular and return migration both within the is-lands and elsewhere to gain waged employment, partly driven by preferential access to labour markets in some industrialised countries (e.g. Australia, New Zealand and the US), have resulted in the increasing importance of remittances in livelihood strategies (24-27). Research is needed to explore how important subsistence produc-tion on the different islands is relative to production for the market and/or waged employment and how histori-cal and recent changes have affected food security and vulnerability.

The success or failure of these strategies is associated with political and economic events in the region. The Pacific Island Countries (PICs) have been relatively marginalised in the intensified economic globalisation partly because of their isolation from the major markets (28). Flows of foreign direct investment are low pri-marily due to what is perceived as a sub-optimal investor climate. State owned companies, often inefficiently managed marketing boards, have controlled the purchase, marketing and export of agricultural cash crops, which traditionally constituted the main sources of the PICs’ foreign exchange revenue together with marine resources (especially tuna), minerals and tourism (29,30). However, most of the state-owned companies have been dismantled as part of World Bank inspired structural adjustment programmes. In general, the public finan-ces of PICs have been in more or less chronic deficit for decades and have only been balanced by substantial bilateral aid flows considered absolutely necessary to sustain economic activities and support job creation. Despite recent ethnically-based violent clashes and the virtual break down of the rule of law (31), the Solomon Islands is presently undergoing a remarkable revival with an annual growth rate of 4-5%, the highest in the Pacific. The growth is led by the primary sector and exports have increased rapidly, not least due to favourable world market prices. Research on the re-structured marketing channels for cash crops, especially copra, produ-ced by smallholders is necessary to understand and predict the effect of reforms on land use, livelihoods and resilience of the production system, including an existing gender-bias towards increasing female workloads in commercial agriculture.

The political-economic challenges are partly a result of the limited resources available and the islands’ vulnera-bility to climate change and resource degradation. The climate has varied substantially over the past 30-50 years with the El Niño/Southern Oscillation (ENSO) phenomenon being the most important factor influencing the general circulation in the region including the risk of drought (32). Tropical hurricane development is the indivi-dual weather phenomenon which has the most devastating effects but the annual frequency of hurricanes in the region varies (33,34). The scenarios for future climate change in the region are still uncertain, in particular chan-ges in tropical hurricane strength and frequency (35,36), and there is no consensus on changes in ENSO. It is ex-pected that the regional future change in sea level will not be dramatically different from the global rise though the magnitude of this rise is still highly uncertain (37). Nonetheless, there is a need for research addressing the vulnerability of agriculture to changes in extreme events and in sea-level. Hurricanes, for example, may have short-term devastating effects but long-term positive effects in terms of replenishing shoreline sediments (6), but systematic accounts of such events and trends are not available. The quantification of the relationship between production/livelihoods and climate will assist in generating scenarios for future livelihoods and for the formula-tion of adaptation strategies.

Conditions for agricultural production are difficult and the maintenance of soil productivity in resource-poor subsistence farming systems is essential as agricultural inputs carry high transport costs. The content of soil nutrients is highly dependent on the pool of soil organic carbon (SOC) (38,39), which is influenced by a range of parameters including soil type, climate and land use. A recent study has demonstrated considerable losses of SOC as a result of shifting cultivation in the Solomon Islands (40), but the rates of these losses are still un-known. No recent studies of the nutrient status of the soils on the islands are available, but a soil survey carried out on Bellona in the early 1970s (41) provides a baseline for establishing the historical changes of the nutrient and SOC pools needed to elucidate long-term effects of land use on soil fertility.

This complex situation of causal relationships driving changes in land use and livelihoods in small island socie-ties needs to be addressed through interdisciplinary analysis in order not to overlook key explanatory factors. Recent research within the land-change science communities has developed conceptual models suitable to guide such analyses (42-44), and the development of efficient remote sensing methods and sources have significantly improved the availability of recent material to document changes. In combination with historical archival material and oral histories this provides an excellent basis for in-depth studies of the historical footprints of contemporary development trends.

3.      Study sites, activities and methodology

Key data of the three islands addressed by this study, Bellona, Ontong Java and Tikopia, are presented in Table 1. Despite the relatively higher altitude of two of the islands, agricultural areas are located in low-lying areas, vulnerable to sea level change and extreme weather. Both research questions will be addressed in all islands and methods employed will be identical, though provision for local differences will be made.

Table 1. Overview of study sites

Changes in land use practices and natural resource management

In order to assess the changes of the land use and natural resource management system,an analysis of current practices will be made, using the early pioneer studies (2,5,7,41) as reference material. For the farming systems, the analyses will focus on relationships between land use practices, yields, vegetation and soil properties. One of the aims is to construct a model that expresses the relationships between current land use, land use history, inhe-rent soil parameters, soil fertility, carbon (C) stocks and turnover rates. Moreover, land tenure arrangements are crucial for understanding land distribution and access, both of which can be key determinants for understanding land use strategies. Assessment of the use of forest products and other terrestrial resources will also be important to obtain a broader understanding of the subsistence economy and pressure on natural resources.

Using the earlier in situ studies as a baseline, current and past land use practices will be assessed using in situ measurements (such as GPS for field sizes, biomass assessment of fallow land, sample crop cuts to estimate yields) as well as retrospective household questionnaire surveys to obtain information on fallow periods, labour use, agrochemical inputs, past yield levels, and land tenure arrangements. The natural resource use will be quan-tified through interviews and transects accompanied by local people for identification of species. The methods used will be similar to previous studies (45,46).

The soil analysis will be based on volume specific soil samples collected according to pedogenic soil horizon to a depth of about one metre. Bulk samples will be analysed for grain size distribution, SOC, pH, nitrogen, phos-phorous, CEC and clay mineralogy. Furthermore, the soil water retention curve, the plant available water con-tent in the root zone, and the water soluble contents of the main nutrients will be determined. Experiments will be carried out to assess the decomposition rates of SOC according to grain-size fraction, clay mineralogy and nutrient availability.

Land use/cover change

The field-based land use change studies mentioned above will be combined with time-series of remote sensing imagery and will also provide ground truth for these. The backbone of the remote sensing analysis will be a time-series of Landsat TM and ETM images covering the period 1982 to date. In order to add a longer time perspective and spatial detail, old aerial photos will be used, combined with new aerial photos where available, and/or imagery from the IKONOS or QuickBird satellites. Satellite images will be acquired in close collabora-tion with the parallel project ‘Satellite Eye for Scientists and the Classroom for Galathea III’, coordinated by Risø National Laboratory, Denmark. Current land use/cover will be mapped in situ using ‘repeat-track inter-ferometric radar’ (ASAR from the ENVISAT satellite), supported by analysis of stereo-pairs of aerial photos and/or optical satellite images as well as in-situ measurements of terrain profiles. This information will feed directly into the satellite image interpretation as well as into the analysis of agricultural yields, labour produc-tivity, land tenure and vulnerability to climate and sea-level change.

A spatial simulation model of the agricultural systems of the islands will be developed to assist the understan-ding of their spatial dynamics and their responses to population growth. The model, developed in a GIS environ-ment, will be validated against observed changes in agricultural land use and, if appropriate, used to produce scenarios of future agricultural intensification driven by population growth. The model will be a modified ver-sion of the general shifting cultivation model already applied to historical data from Bellona (2,47).

Livelihoods and economic development

In order to arrive at a complete understanding of the survival of the populations of the Solomon Islands, the land use system analyses will be complemented by a broader analysis of livelihood strategies and economic opportu-nities and constraints for development. To gain an understanding of how different groups in the societies think and act, small groups of islanders will be selected for interview varying by both gender and generation to provi-de different perspectives on livelihoods on the islands, such as temporal changes (especially old people) and future aspirations and plans (especially young people). Information on the relative importance of agriculture, fishing, formal and informal employment, migration and remittances in the livelihood strategies will be obtained from the household questionnaire survey employed for the land use study. Subsequently, in order to gain an in-depth understanding of how differing household livelihood strategies develop over time, a range of households will be selected for more detailed analysis.

The relationship between agriculture, livelihoods and the world markets will be examined by the implementa-tion of a number of global commodity chain (GCC) analyses. In principle, GCC analysis tracks the commodity from its place of origin/production to private consumers via intermediary segments of traders, shippers, expor-ters, importers, etc. In addition to the material flow of the commodity, the GCC analysis examines the organisa-tional and political dynamics, at local, national and global levels, that governs the relations between the produ-cers of major export crops (copra, cocoa, palm oil) in the Solomon Islands and consumers in the end markets. A detailed understanding of the present state of world market integration is necessary for an improved and sustain-able exploitation of natural resources and planning of policies for land use as well as land tenure.

Adaptation to climate change

In order to quantify the influence of climate and weather variability (the predictands) on agricultural production and livelihoods (the predictors), linear methods (such as canonical correlation analysis, singular value decompo-sition) and possibly also non-linear methods, for extreme events like the influence of tropical hurricanes, will be employed. The analysis will use data from synoptic climate stations, ”nearby” radiosonde, meteorological satel-lites and archives. Furthermore, climate data will be collected in the household survey to gauge local knowledge on climate change. The period covered will be the last 30-50 years. The relationships between climate and the predictors will be based on or verified using the observed data.

Once the potential relationships are identified, the influence of future climate change on the predictors will be estimated. To estimate the future climate, a number of climate change scenario simulations will be performed with a detailed regional climate model (HIRHAM) run at a horizontal resolution of 15 km, covering an area of approximately 2000 by 2000 km around the Solomon Islands. The climate change simulations will be based on the IPCC emission SRES scenarios A1B and B2. The lateral boundary conditions for the simulations will be taken from global coupled atmosphere-ocean simulations with the German model ECHAM5/OM1.

4.      Research schedule and timetable

The research will be conducted by interdisciplinary teams on each island. The teams will include expertise in 1) land use/cover change, 2) natural resources and climate and 3) livelihood strategies and economic development. A preparatory mission will be undertaken in September 2006 (jointly with the project ‘Migration and Culture in the Western Pacific’). Immediately before the main fieldwork, a pilot study will be undertaken to test methods and ensure, to the extent possible, their uniform application on all of the islands (Table 2).

Table 2. Time schedule, distribution of research teams and activities.

¹ Acronyms of DK-researchers (timing of international partners to be determined):  AEC=Andreas Egelund Christensen, AR=Anette Reenberg, BE=Bo Elberling, BF=Bjarne Fog, HBM=Henrik Breuning-Madsen, JA=Jytte Agergaard, JG=Jens Grundtmann, KG=Kate Gough, KR=Kjeld Rasmussen, LK=Lars Krogh, NF=Niels Fold, OM=Ole Mertz, RF=Rasmus Fensholt, SC=Sofus Christiansen, SK=Søren Kristensen, TBB=Thilde Bech Bruun, TBT=Torben Birch-Thomsen, WM=Willi May

5.      Project organisation and relation to other research activities

The project will be hosted by the Institute of Geography, University of Copenhagen (IGUC) where the project will be an integral part of the activities of the ‘Environment and Society in Developing Countries’ research group (http://www.geogr.ku.dk/research). This group consists of an interdisciplinary team of researchers with expertise ranging from soil science, land use/cover to international development studies. The present project is closely linked to research on land use/cover change in West Africa and Southeast Asia under the Danish Research Network for Land System Science (LaSys), SEREIN, SLUSE and USEPAM projects, adaptation to climate change in the AMMA project and the project Rural-urban Dynamics in a Globalizing World. In all of these projects, IGUC is one of the lead partners. IGUC is moreover hosting the Research Network for Environ-ment and Development (ReNED) with communication of research results to users as a main objective.

The Danish Meteorological Institute (DMI) is the other key partner institution. The work will be carried out by the Climate Research Division, which has about 8 years of experience with climate modeling and analysis of climate processes at an international level. The division plays and has played a key role – in several cases as coordinator – in a considerable number of international research projects on climate change and variability and related physical processes, such as the ongoing ENSEMBLES project (EU FP6). Furthermore employees in the division play an active role in the IPCC (Intergovernmental Panel on Climate Change) work and in advising the Danish society on issues related to climate change.

The local partners in the Solomon Islands will be the University of the South Pacific, Solomon Islands Campus, Honiara as well as the local councils governing the islands. We will also collaborate with regional and international institutions through the project Scientific Committee composed of researchers with significant experience from the region: Professor Randy Thaman, University of the South Pacific, Fiji; Professor John Connell, School of Geosciences, University of Sydney, Australia; Dr. Tim Bayliss-Smith, University Reader in Pacific Geography, Department of Geography, University of Cambridge, UK; and Dr. Jefferson Fox, Senior Fellow, East West Center Hawaii, USA. The Scientific Committee will provide comments on the detailed research design and draft review papers and, as far as possible, participate in the fieldwork.

Moreover, students from the University of the South Pacific, Solomon Island Campus are expected to take part in the project.

6.      Plans for publication and dissemination

The preliminary results of the project will be communicated to the media present on the Galathea3 expedition as the researchers meet Galathea3. It will moreover be ensured that research results are communicated to authorities in the Solomon Islands in a form that is readily accessible to government administrators and underlines the possible application of results to development planning. Finally, the research will be communica-ted in peer-reviewed journals focusing on interdisciplinary studies of land use and the environment, such as Ambio, Agriculture, Ecosystems and Environment, Human Ecology, World Development etc.

7.      Assessment of the significance for future research and research training

This research will be an important part of the global land use/cover change assessments, which aim at establish-ing predictive capacity of impacts of climate change, population growth and other globalisation processes. Fur-ther refinement of such models and their applicability at local level will depend on this type of research. The results will moreover be used in on-going efforts at strengthening high school education in natural sciences. It will also feed necessary case studies into the courses at Bachelor and Master’s level at the Institute of Geogra-phy as well as for the PhD school focusing on land use/cover change and globalisation processes.

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