Desertification, resulting from climatic variability and irrational human activities, is currently one of the most important environmental problems. Because desertification has brought poverty, famine, and displacement, hindering the improvement of eco-environment and social-economy in the developing countries and regions, it has attracted the attention of the whole world. Since 1994, when the United Nations Convention to Combat Desertification (UNCCD) was established, all kinds of battles against desertification have been conducted worldwide with hopes to bring about a positive change.

Nevertheless, a large number of questions concerning desertification still remain, depending on the different contexts and objectives of national strategies (Xue et al., 2015; Muñoz-Rojas et al., 2021). The large gap between sciences and policies concerning the rehabilitation of the desertified land requires urgent attention in many countries. To design effective land restoration and rehabilitation strategies and achieve the global goals for sustainable development, including Land Degradation Neutrality, a systemic and comprehensive understanding of desertification and rehabilitation is necessary (see discussions in: Wang et al., 2015; Kong et al., 2021; Xue, 2022). Following a brief conceptual overview and an introduction to the context and planning of Chinese national investments in land rehabilitation, this Editorial introduces fifteen collected contributions to this debate from interested scientists in China.

Due to the scale of the land degradation, desertification and drought challenges in China, it accounts for a large portion of the total area of degraded land globally (Alexander et al., 2019)1. The achievement of the global target for land degradation neutrality and the objectives of the UN Decade on Ecosystem Restoration will depend on significant progress to be made in China. The Chinese Government is investing heavily in the achievement of its ecological objectives, and reporting substantial achievements (PRC, 2021). For example, from 2015 to 2018, the net area of land restored in China was calculated to account for about one fifth of the global total. On this basis, the 2021 Chinese Voluntary National Review stated that China had restored more land than any other country (PRC, 2021 p28). The role of Chinese scientists, and their commentaries on this achievement should therefore be of considerable interest to the international-science-policy community (Kong et al., 2021).

Conceptual Framings of Desertification, Degradation, Rehabilitation and Restoration
According to the UNCCD, “desertification” means land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities; “land” means the terrestrial bio-productive system (that comprises soil, vegetation, other biota, and the ecological and hydrological processes that operate within the system); and “land degradation” means reduction or loss of the biological or economic productivity and complexity in that terrestrial system. More recently, the millennium ecosystem assessment has defined measures of productivity (or loss of productivity) in terms of ecosystem services. The Paris Agreement has captured emerging understanding of the complexity of food-related aspects of the terrestrial system.

According to the United Nations Convention for Combatting Desertification (Article 1b)2, “Combating desertification” includes activities which are part of the integrated development of land for sustainable development which are aimed at: (i) prevention and/or reduction of land degradation; (ii) rehabilitation of partly degraded land; and (iii) reclamation of desertified land. Rehabilitation aims to improve to some degree a degraded site by re-establishing associated ecosystem functions such as trophic interactions, water, and nutrient cycles (Gurr et al., 2014). The goals are determined by what society wants and needs, the level of degradation, and the economic, political, and social environment (Gurr et al., 2014). Dryland ecologists observe a distinction between the limited objectives of ecosystem rehabilitation versus the more ambitious agenda for ecological restoration (Aronson et al., 1999; Alexander et al., 2016).

Rehabilitation is used to refer to restoration activities that may fall short of fully restoring the biotic community to its pre-degradation state, including natural regeneration and emergent ecosystems (Fisher et al., 2018 p6). The Society for Ecological Restoration (SER) defines standards for rehabilitation as follows (Gann et al., 2019):

Rehabilitation–management actions that aim to reinstate a level of ecosystem functioning on degraded sites, where the goal is renewed and ongoing provision of ecosystem services rather than the biodiversity and integrity of a designated native reference ecosystem.