1,298 publications from this institution
This session will explore the benefits and potential risks of implementing nature-based solutions. It will cover land and marine-based approaches, and will examine some key case-studies, including peatlands and REDD+.
Feeding 9–10 billion people by 2050 and preventing dangerous climate change are two of the greatest challenges facing humanity. Both challenges must be met while reducing the impact of land management on ecosystem services that deliver vital goods and services, and support human health and well-being. While supply-side mitigation measures, such as changes in land management, might either enhance or negatively impact food security, demand-side mitigation measures, such as reduced waste or demand for livestock products, should benefit both food security and greenhouse gas (GHG) mitigation. Demand-side measures offer a greater potential (1.5–15.6 Gt CO 2 -eq. yr -1 ) in meeting both challenges than do supply-side measures (1.5–4.3 Gt CO 2 -eq. yr -1 at carbon prices between 20 and 100 US$ tCO 2 -eq. yr -1 ), but given the enormity of challenges, all options need to be considered. Supply-side measures should be implemented immediately, focusing on those that allow the production of more agricultural product per unit of input. For demand-side measures, given the difficulties in their implementation and lag in their effectiveness, policy should be introduced quickly, and should aim to co-deliver to other policy agendas, such as improving environmental quality or improving dietary health.
Abstract. Many former estimates of regional scale C sequestration potential have made use of linear regressions based on long‐term experimental data, whilst some have used dynamic soil organic matter (SOM) models linked to spatial databases. Few studies have compared the two methods. We present a case study in which the potential of different land management practices to sequester carbon in soil in arable land is estimated by different methods. Two dynamic SOM models were chosen for this study, RothC (a soil process model) and CENTURY (a whole ecosystem model with a SOM module). RothC and CENTURY are the two most widely used and validated SOM models worldwide. A Geographic Information System (GIS) containing soil, land use and climate layers, was assembled for a case study in central Hungary. GIS interfaces were developed for the RothC and CENTURY models, thus linking them to the spatial datasets at the regional level. This allowed a comparison of estimates of the C sequestration potential of different land management practices obtained using the two models and using regression based approaches. Although estimates obtained by the different approaches were of the same order of magnitude, differences were observed. Some of the land management scenarios studied here showed sufficient C mitigation potential to meet Hungarian CO 2 reduction commitments. For example, afforestation of 12% current arable land could sequester 0.042–0.092 Tg yr –1 in the soil alone, or 0.285–0.588 Tg C yr –1 in both soil and biomass; 1990 level CO 2 emissions for the study area were 4.7 Tg C with a corresponding reduction commitment of 0.282 Tg C. It is not, however, suggested that this is the only, or the most favourable way, in which to meet the commitments.
Nitrous oxide (N2O) is a potent greenhouse gas in the atmosphere and its emissions are of great concern worldwide. This Chapter reviews the production and importance of nitrous oxide from agricultural soils and provides examples of management practices that may affect the extent of emissions from both grasslands and cereal systems. In addition, the use of geochemical models to estimate the present and future emissions of nitrous oxide is shown using DeNitrification-DeComposition (DNDC) and DayCent (Daily Century) models as working examples.