A method for calculating a land‐use change carbon footprint (LUC‐CFP) for agricultural commodities – applications to Brazilian beef and soy,Indonesian palm oil

The world's agricultural system has come under increasing scrutiny recently as an important driver of global climate change, creating a demand for indicators that estimate the climatic impacts of agricultural commodities. Such carbon footprints, however, have in most cases excluded emissions from land‐use change and the proposed methodologies for including this significant emissions source suffer from different shortcomings. Here, we propose a new methodology for calculating land‐use change carbon footprints for agricultural commodities and illustrate this methodology by applying it to three of the most prominent agricultural commodities driving tropical deforestation: Brazilian beef and soybeans, and Indonesian palm oil. We estimate land‐use change carbon footprints in 2010 to be 66 tCO₂/t meat (carcass weight) for Brazilian beef, 0.89 tCO₂/t for Brazilian soybeans, and 7.5 tCO₂/t for Indonesian palm oil, using a 10 year amortization period. The main advantage of the proposed methodology is its flexibility: it can be applied in a tiered approach, using detailed data where it is available while still allowing for estimation of footprints for a broad set of countries and agricultural commodities; it can be applied at different scales, estimating both national and subnational footprints; it can be adopted to account both for direct (proximate) and indirect drivers of land‐use change. It is argued that with an increasing commercialization and globalization of the drivers of land‐use change, the proposed carbon footprint methodology could help leverage the power needed to alter environmentally destructive land‐use practices within the global agricultural system by providing a tool for assessing the environmental impacts of production, thereby informing consumers about the impacts of consumption and incentivizing producers to become more environmentally responsible.     

Carbon outcomes of major land‐cover transitions in SE Asia: great uncertainties and REDD+ policy implications

Policy makers across the tropics propose that carbon finance could provide incentives for forest frontier communities to transition away from swidden agriculture (slash‐and‐burn or shifting cultivation) to other systems that potentially reduce emissions and/or increase carbon sequestration. However, there is little certainty regarding the carbon outcomes of many key land‐use transitions at the center of current policy debates. Our meta‐analysis of over 250 studies reporting above‐ and below‐ground carbon estimates for different land‐use types indicates great uncertainty in the net total ecosystem carbon changes that can be expected from many transitions, including the replacement of various types of swidden agriculture with oil palm, rubber, or some other types of agroforestry systems. These transitions are underway throughout Southeast Asia, and are at the heart of REDD+ debates. Exceptions of unambiguous carbon outcomes are the abandonment of any type of agriculture to allow forest regeneration (a certain positive carbon outcome) and expansion of agriculture into mature forest (a certain negative carbon outcome). With respect to swiddening, our meta‐analysis supports a reassessment of policies that encourage land‐cover conversion away from these [especially long‐fallow] systems to other more cash‐crop‐oriented systems producing ambiguous carbon stock changes – including oil palm and rubber. In some instances, lengthening fallow periods of an existing swidden system may produce substantial carbon benefits, as would conversion from intensely cultivated lands to high‐biomass plantations and some other types of agroforestry. More field studies are needed to provide better data of above‐ and below‐ground carbon stocks before informed recommendations or policy decisions can be made regarding which land‐use regimes optimize or increase carbon sequestration. As some transitions may negatively impact other ecosystem services, food security, and local livelihoods, the entire carbon and noncarbon benefit stream should also be taken into account before prescribing transitions with ambiguous carbon benefits.     

Bioenergy production and Skylark (Alauda arvensis) population abundance – a modelling approach for the analysis of land‐use change impacts and conservation options

Bioenergy production is seen as one way of meeting future energy needs. The growing demand for biomass for energy production induces the cultivation of a few fast growing and high‐yielding energy crops on vast areas of arable land. This land‐use change has been found associated with the reduction of habitat suitability for farmland birds and a decline in farmland biodiversity in general. A large number of studies have assessed the ecological effects of energy crop cultivation at the local scale of a single field. This study focuses on regional landscape changes caused by increased energy crop cultivation, which includes reduction of crop‐type richness and spatial concentration of single crop‐types. We present a spatially explicit ecological model to assess the population‐level consequences of these effects on the abundance of the farmland bird species Skylark (Alauda arvensis). We also investigate the impacts of different land‐use scenarios and aim to identify adaptive conservation options. We show that (1) the impacts of increased energy crop cultivation on Skylark population abundance depend strongly on the landscape structure; (2) impacts could be tolerated as long as a certain minimum level of crop‐type heterogeneity is retained at the landscape level and (3) conservation actions are required and effective especially on landscapes where crop‐field size is large.