Interlinkages between desertification, land degradation, food security and greenhouse gas fluxes: Synergies, trade-offs and SPM6 integrated response options Coordinating Lead Authors: Pete Smith (United Kingdom), Johnson Nkem (Cameroon), Katherine Calvin (The United States of America) Lead Authors: Donovan Campbell (Jamaica), Francesco Cherubini (Norway/Italy), Giacomo Grassi (Italy/European Union), Vladimir Korotkov (The Russian Federation), Anh Le Hoang (Viet Nam), Shuaib Lwasa (Uganda), Pamela McElwee (The United States of America), Ephraim Nkonya (Tanzania), Nobuko Saigusa (Japan), Jean-Francois Soussana (France), Miguel Angel Taboada (Argentina) Contributing Authors: Cristina Arias-Navarro (Spain), Otavio Cavalett (Brazil), Annette Cowie (Australia), Joanna House (United Kingdom), Daniel Huppmann (Austria), Jagdish Krishnaswamy (India), Alexander Popp (Germany), Stephanie Roe (The Philippines/The United States of America), Raphael Slade (United Kingdom), Lindsay Stringer (United Kingdom), Matteo Vizzarri (Italy) Review Editors: Amjad Abdulla (Maldives), Ian Noble (Australia), Yoshiki Yamagata (Japan), Taha Zatari (Saudi Arabia) Chapter Scientists: Frances Manning (United Kingdom), Dorothy Nampanzira (Uganda) This chapter should be cited as: Smith, P., J. Nkem, K. Calvin, D. Campbell, F. Cherubini, G. Grassi, V. Korotkov, A.L. Hoang, S. Lwasa, P. McElwee, E. Nkonya, N. Saigusa, J.-F. Soussana, M.A. Taboada, 2019: Interlinkages Between Desertification, Land Degradation, Food Security and Greenhouse Gas Fluxes: Synergies, Trade-offs and Integrated Response Options. In: Climate Change and Land: an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems [P.R. Shukla, J. Skea, E. Calvo Buendia, V. Masson-Delmotte, H.- O. Portner, D. C. Roberts, P. Zhai, R. Slade, S. Connors, R. van Diemen, M. Ferrat, E. Haughey, S. Luz, S. Neogi, M. Pathak, J. Petzold, J. Portugal Pereira, P. Vyas, E. Huntley, K. Kissick, M. Belkacemi, J. Malley, (eds.)]. In press. 551 Chapter 6 Interlinkages between desertification, land degradation, food security and greenhouse gas fluxes Table of contents Executive summary ..................................................................................... 553 6.4.2 Sensitivity of the integrated response options to climate change impacts ........................... 623 6.1 Introduction ........................................................................................... 556 Cross-Chapter Box 8 | Ecosystem services and Nature’s Contributions to People, and 6.1.1 Context of this chapter ....................................................... 556 their relation to the land–climate system ....................... 625 6.1.2 Framing social challenges and 6.4.3 Impacts of integrated response acknowledging enabling factors ................................ 556 options on Nature’s Contributions 6.1.3 Challenges and response options in current to People (NCP) and the UN Sustainable ........................................... and historical interventions 558 Development Goals (SDGs) ............................................ 627 Box 6.1 | Case studies by anthrome type 6.4.4 Opportunities for implementing showing historical interlinkages between integrated response options ......................................... 633 land-based challenges and the development Cross-Chapter Box 9 | Climate and of local responses................................................................................. 561 land pathways ..................................................................................... 641 6.1.4 Challenges represented in future scenarios ........ 564 6.4.5 Potential consequences of delayed action ........... 644 6.2 Response options, co-benefits and adverse Frequently Asked Questions ................................................................. 646 side effects across the land challenges ......................... 565 6.2.1 Integrated response options based FAQ 6.1: What types of land-based options can help mitigate and adapt to climate change? ............. 646 on land management ........................................................ 569 6.2.2 Integrated response options based FAQ 6.2 Which land-based mitigation measures could affect desertification, on value chain management ........................................ 576 land degradation or food security? ..................................... 646 6.2.3 Integrated response options based FAQ 6.3: What is the role of bioenergy on risk management .......................................................... 576 in climate change mitigation, and what Cross-Chapter Box 7 | Bioenergy are its challenges? .............................................................................. 646 and bioenergy with carbon capture and storage (BECCS) in mitigation scenarios ......................... 580 References .......................................................................................................... 647 6.3 Potentials for addressing the land challenges ......... 583 6.3.1 Potential of the integrated response options for delivering mitigation ............................... 583 6.3.2 Potential of the integrated response options for delivering adaptation .............................. 589 6.3.3 Potential of the integrated response options for addressing desertification .................... 595 6.3.4 Potential of the integrated response options for addressing land degradation .............. 599 6.3.5 Potential of the integrated response options for addressing food security ....................... 603 6 6.3.6 Summarising the potential of the integrated response options across mitigation, adaptation, desertification land degradation and food security ......................... 609 6.4 Managing interactions and interlinkages .................... 618 6.4.1 Feasibility of the integrated response options with respect to costs, barriers, saturation and reversibility ............................................ 618 552 Interlinkages between desertification, land degradation, food security and greenhouse gas fluxes Chapter 6 Executive summary Two further options with large mitigation potential, dietary change and reduced food waste, have no global estimates for adaptation The land challenges, in the context of this report, are but show no negative impacts across the other challenges. climate change mitigation, adaptation, desertification, land Five options: improved cropland management; improved grazing degradation, and food security. The chapter also discusses land managements; agroforestry; integrated water management; implications for Nature’s Contributions to People (NCP), including and forest management, have moderate mitigation potential, with biodiversity and water, and sustainable development, by assessing no adverse impacts on the other challenges (high confidence). {6.3.6} intersections with the Sustainable Development Goals (SDGs). The chapter assesses response options that could be used to address these Sixteen response options have large adaptation potential (more challenges. These response options were derived from the previous than 25 million people benefit), without adverse side effects chapters and fall into three broad categories: land management, on other land challenges (high confidence). These are increased value chain, and risk management. food productivity, improved cropland management, agroforestry, agricultural diversification, forest management, increased soil The land challenges faced today vary across regions; climate organic carbon content, reduced landslides and natural hazards, change will increase challenges in the future, while socio- restoration and reduced conversion of coastal wetlands, reduced economic development could either increase or decrease post-harvest losses, sustainable sourcing, management of supply challenges (high confidence). Increases in biophysical impacts from chains, improved food processing and retailing, improved energy climate change can worsen desertification, land degradation, and use in food systems, livelihood diversification, use of local seeds, and food insecurity (high confidence). Additional pressures from socio- disaster risk management (high confidence). Some options (such as economic development could further exacerbate these challenges; enhanced urban food systems or management of urban sprawl) may however, the effects are scenario dependent. Scenarios with increases not provide large global benefits but may have significant positive in income and reduced pressures on land can lead to reductions in local effects without adverse effects (high confidence). {6.3, 6.4} food insecurity; however, all assessed scenarios result in increases in water demand and water scarcity (medium confidence). {6.1} Seventeen of 40 options deliver co-benefits or no adverse side effects for the full range of NCPs and SDGs; only three The applicability and efficacy of response options are options (afforestation, bioenergy and bioenergy with carbon region and context specific; while many value chain and risk capture and storage (BECCS), and some types of risk sharing management options are potentially broadly applicable, many instruments, such as insurance) have potentially adverse side land management options are applicable on less than 50% of effects for five or more NCPs or SDGs medium( confidence). the ice-free land surface (high confidence). Response options The 17 options with co-benefits and no