Harnessing the climate commons: an agent-based modelling approach to making reducing emission from deforestation and degradation (REDD)+work

Humans have created a worldwide tragedy through free access to the global common atmosphere. The Conference of the Parties (COP) on climate change increased political commitment to reduce emission from deforestation and degradation and to enhance carbon stocks (REDD+). However, government sectors, political actors, business groups, civil societies, tree growers and other interest groups at different levels may support or reject REDD+. The paper used Arena-Actor-Institution concept to understand REDD+and provides agent-based modeling approach to harnessing its processes. The model explores: (a) how providers are likely to decrease or increase carbon stocks on their landscapes under ‘business as usual’ institutions; (b) how they are likely to negotiate with potential buyers with regards to the involvement of brokers (governments or nongovernmental organizations); and (c) how altruism and collaboration can affect the affectivity of REDD+. The model was developed as a spatially explicit model to consider the complexity of REDD+target landscapes. The simulation results are examined against the 3E+criteria, i.e. effectiveness in carbon emission reduction, cost efficiency and equity among involved stakeholders and co-benefit of other activities. This study took the Jambi landscape in Indonesia as a case. The results explain how REDD+agreement areas increase with higher carbon prices, e.g. US$25 or US$35. However, the simulation also shows that even with low carbon prices GHG emissions will decrease if the altruism degree and collective actions of the actors increases. The paper describes institutional arrangements which would help to harness the global commons of climate change.     

Removal of organic polyelectrolytes and their metal complexes by adsorption onto xonotlite

Natural organic polyelectrolytes (humic and fulvic acids) and their metal complexes were removed by adsorption onto xonotlite. The removal percentages of humic and fulvic acids by xonotlite were approximately 80% and 30%, respectively. Humic acid removal from solution by adsorption onto xonotlite took place more readily than fulvic acid removal. The molecular weight distributions of the humic substances remaining in solution after adsorption with the xonotlite were measured with size exclusion chromatography. A comparison of molecular weight distributions demonstrated conclusively that large molecular weight components were adsorbed preferentially, indicating that adsorption efficiency depends on the number of functional groups of humic substances. Furthermore, the surface topography of the adsorbent was observed before and after adsorption by scanning electron microscopy. The calculated heat of adsorption was of 330 kJ mol(-1) which was evaluated from the Clapeyron-Clausius equation. Therefore, the adsorption type can be considered chemical. Since xonotlite can be easily synthesized and obtained at low cost, the adsorption method of humic and fulvic acids is superior to their precipitation.