Agent based simulation of a small catchment water management in northern Thailand: Description of the CATCHSCAPE model

Due to mounting human pressure, stakeholders in northern Thailand are facing crucial natural resources management (NRM) issues. Among others, the impact of upstream irrigation management on downstream agricultural viability is a growing source of conflict, which often has both biophysical and social origins. As multiple rural stakeholders are involved, appropriate solutions should only emerge from negotiation. CATCHSCAPE is a Multi-Agent System (MAS) that enables us to simulate the whole catchment features as well as farmer’s individual decisions. The biophysical modules simulate the hydrological system with its distributed water balance, irrigation scheme management and crop and vegetation dynamics. The social dynamics are described as a set of resource management processes (water, land, cash, labour force). Water management is described according to the actual different levels of control (individual, scheme and catchment). Moreover, the model’s architecture is presented in a way that emphasises the transparency of the rules and methods implemented. Finally, one simulated scenario is described along with its main results, according to different viewpoints (economy, landscape, water management).     

Emission study of a diesel engine fueled with higher alcohol-biodiesel blended fuels

This work examines the effect of butanol (higher alcohol) on the emission pattern of neat neem oil biodiesel (NBD100) fueled diesel engine. Single-cylinder, 4-stroke, research diesel engine was employed to conduct the trial. Blends comprising the mixture of biodiesel and higher alcohol were prepared by employing an ultrasonic agitator. Four test fuels such as neat neem oil biodiesel, diesel, and two blends of higher alcohol/neem oil biodiesel: 10% and 20% (by volume). Experimental result showed that increasing alcohol content to biodiesel brought down the various emissions such as Smoke, NO_x, HC, and CO by 6.8%, 10.4%, 8.6%, and 5.9%, respectively, at all loads. It was also concluded from the trail that a 20% higher alcohol/neem oil biodiesel blends show the promising signs in reducing all the emissions associated with biodiesel fuelled diesel engine.     

Modelling interactions between scavenger behaviour and farming practices: Impacts on scavenger population and ecosystem service efficiency

Long term conservation of ecosystem services requires a deep understanding of their basic processes and the development of tools to assess the effects of human practices on their efficiency. As an example of recycling service, we focus on the consumption of livestock carcasses by obligate scavengers, taking the case of vultures which face a dramatic decline worldwide. We investigate whether maintaining this recycling service through individual feeding stations called light feeding stations in contrast to aggregated resource on heavy feeding stations can meet the double objectives of vulture conservation and service efficiency. We built a spatially explicit multi-agent model to investigate the long term effects of livestock farmers practices on both the recycling service efficiency for farmers and vulture population carrying capacity including: (i) carcass disposal practices that drive the quantity and spatial distribution of resources for vultures and (ii) temporal distribution of livestock mortality due to economic choices that drive the dynamics of resources for vultures. In addition, we examine various scenarios related to vulture feeding behaviour - i.e. central place vs. random foraging and contest vs. scramble intraspecific competition - that may play a role in the vulture carrying capacity and recycling service efficiency. When accounting for vulture central place foraging, we found that favouring the use of light feeding stations instead of heavy feeding station does not affect vulture population carrying capacity and increases the number of farmer for which vulture service is optimal. The increase of light feeding station users poorly affects the number of farmers for which vulture service is optimal in contrast to results obtained with a vulture random foraging behaviour. Both of the recycling service efficiency and the vulture carrying capacity vary with the kind of intraspecific competition and with the seasonal distribution of livestock mortality. Livestock mortality distributions with a seasonal peak of mortality result in a mismatch between vulture food requirement and farmers needs for carcass removal. Finally we raise several points on the relevance of light feeding stations as a sustainable management for vulture conservation and for the recycling service and discuss the potential implications of seasonal scarcity of resources due to farming economic constraints.