International audienceThe ‘4 per mille Soils for Food Security and Climate’ was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia). We asked whether the 4 per mille initiative is feasible for the region. The outcomes highlight region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates globally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha−1), and at the first twenty years after implementation of best management practices. In addition, areas which have reached equilibrium will not be able to further increase their sequestration. We found that most studies on SOC sequestration only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille number was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille in the top 1m of global agricultural soils, SOC sequestration is between 2-3 Gt C year−1, which effectively offset 20–35% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become viable. The challenge for cropping farmers is to find disruptive technologies that will further improve soil condition and deliver increased soil carbon. Progress in 4 per mille requires collaboration and communication between scientists, farmers, policy makers, and marketeers

Legacy soil data have been produced over 70 years in nearly all countries of the world. Unfortunately, data, information and knowledge are still currently fragmented and at risk of getting lost if they remain in a paper format. To process this legacy data into consistent, spatially explicit and continuous global soil information, data are being rescued and compiled into databases. Thousands of soil survey reports and maps have been scanned and made available online. The soil profile data reported by these data sources have been captured and compiled into databases. The total number of soil profiles rescued in the selected countries is about 800,000. Currently, data for 117, 000 profiles are compiled and harmonized according to GlobalSoilMap specifications in a world level database (WoSIS). The results presented at the country level are likely to be an underestimate. The majority of soil data is still not rescued and this effort should be pursued. The data have been used to produce soil property maps. We discuss the pro and cons of top-down and bottom-up approaches to produce such maps and we stress their complementarity. We give examples of success stories. The first global soil property maps using rescued data were produced by a top-down approach and were released at a limited resolution of 1km in 2014, followed by an update at a resolution of 250m in 2017. By the end of 2020, we aim to deliver the first worldwide product that fully meets the GlobalSoilMap specifications.

Crop production needs to double to feed the world’s growing population. Indonesia, as the fourth most populated country in the world, needs to meet its food security challenge with a shrinking arable land area. Indonesia has over 34 million ha of swampland. The scarcity of arable land in Indonesia means wetlands are likely to be converted to agricultural use. The challenge is to both profitably and sustainably do so. This paper presents a framework for developing wetlands for food production, which includes (1) the characterization of land and problem of development; (2) analysis of historical development and lessons learned; (3) technology development; and (4) optimization of development. We analyze each of the components and its relation to regional economic growth and lessons learned. For successful future wetland development, three factors must be considered: Land-soil-water characterization, landscape and land use design, and community development. This framework can be adopted by other tropical areas for the development of wetlands.

Indonesia is the fourth most populated country in the world with an annual population growth rate of 1.3%. This growth is accompanied by an increase in sugar consumption, which is occurring at an annual rate of 4.3%. The huge demand for sugar has created a large gap between sugar production and demand. Indonesia became the world’s largest sugar importer in 2017–2018. Sugarcane farmers have an important role in sugar production. They are facing problems with declining sugarcane productivity and arable land decreasing. We aimed to understand the sugar production issue in Indonesia and to examine options to increase sugar production. To achieve these aims, a framework consisting of four steps was developed: Analysis of the current situation; problems identification; resolution; and delivering programs; and strategies. The main problems in sugar production in Indonesia were identified, including a stagnation in sugarcane harvest area, low sugarcane productivity, lack of good varieties, and inefficient sugar mills. Based on the identified problems, strategies to increase production were created. Two approaches need to be executed simultaneously: An increase in sugarcane planting area, and an increase in productivity and sugar yield. The first approach in increasing sugar production is the exploration of new sugarcane planting areas outside of Java both on existing agricultural land and in new areas. A land suitability analysis for the whole country was conducted based on a semi-detailed soil map. The main priority for development was the existing agricultural area via an integration system or existing crop exchange. The second approach is restructuring sugar factories through the revitalization of existing sugar mills and investment in the construction of new mills. The challenges that need to be addressed include land availability, provision of high-yielding varieties, and improving the efficiency of sugar mills. General strategies and medium-term programs are presented and discussed. These efforts, if well-executed, will boost Indonesia’s sugar production to meet its domestic demand by 2025, achieving competitiveness in the world market by 2045.