Traversing the landscapes of dryland regions around the world one experiences the connections between climate and ecosystems and the vulnerability of human activities to vagaries of the changing elements. From the rain shadows of continental and mountainous regions to the vast windswept landscapes of the horse latitudes, the seasonal cycles and availability of water controls the life patterns of the vegetation, wildlife, and the people who inhabit these regions. Ecosystems and societies have evolved to match these rhythms over millennia of coexistence. From desiccated and parched landscapes and water courses life springs forth with the return of growing season moisture. Arid lands support a variety of life and livelihoods, which have evolved over millennia of climate weather patterns structuring the cycle of ecosystem services. Water availability and access are essential in connecting the environment to biological responses and ecosystem processes.
This rhythm is being disrupted by climate change over the past several decades. The warming climate has resulted in longer and more intensive droughts, fire seasons extending over more seasons, and severe rainfall events exacerbating erosion of landscapes. The consequence of these climate changes is challenging ecosystems and people across the global drylands. Recently, in the central plains region of the United States, “flash droughts” have literally sucked the life out of ecosystems. These flash droughts are in response to the increased warming during the growing season increasing the evaporative demand of the atmosphere drawing moisture from the soil and vegetation, even if the winter recharge has been adequate.
The fire seasons in many semiarid regions have become a year-round threat resulting in the loss of critical land resources. Fires in the dryland systems are consuming grasslands, crops and metropolitan areas throughout the world, with several areas in Australia under threat in late 2019 and further damages projected in the early part of 2020.
The onset of the rainy season in these regions provides temporary relief to persistent droughts. However, the intensification of rainfall in these regions is causing flash floods and increased erosion, especially in fire-scarred landscapes. The loss of topsoil in these fragile ecosystems reduces the potential forage productivity of these landscapes.
These dryland ecosystems cover approximately 45% of the world’s land surface and support 40% of the global population. They also hold approximately a third of the biodiversity hot spots and provide habitat for 28% of endangered species. Though these lands are diverse and their peoples are innovative in the face of tough environments, they are especially sensitive and vulnerable to rapid rates of physical and social changes. Water crisis, land degradation and/or desertification is pervasive and leading to a potential collapse of life support systems in some drylands. It has posed far-reaching impacts on the livelihoods of marginalized peoples locally, and it drives migration, unrest and economic instability at regional and global levels. Both local communities and institutions, and global policy systems, need to innovate with the support of actionable research, in order to help drylands become more resilient and avoid increasingly catastrophic disruptions due to future change.
From a systems point of view, drylands are strongly coupled social and ecological systems (SES) whose ecological management and sustainability are heavily influenced by people. This SES perspective is incorporated in the development of a new research program to assess changes in ecosystem dynamics, the impacts on social-ecological interactions, and the response strategies of SES to meet challenges due to climate and other changes impacting these dryland regions. This new international initiative, Global Dryland Ecosystem Program (Global-DEP), is aimed at developing an actionable research agenda to support sustainable dryland social-ecological systems that advance ecosystem management and sustainable livelihoods in the context of Sustainable Development Goals (SDGs):
- Understand how dryland ecosystems of the world will respond to global environmental changes
- Promote researchers to facilitate the development of pathways to support enhanced social-ecological system resilience and sustainable development in these dryland ecosystems
Global-DEP will act as a platform for integration of insight from different disciplines on dryland ecosystems within social-ecological processes and contribution to SDGs. Its main objectives are:
- Quantify the magnitude and direction of changes and feedback of dryland ecosystems to earth system and societal processes.
- Determine the factors controlling vulnerability and resilience of dryland ecosystems.
- Reveal the impact of global environmental changes to ecosystem services, human-well-being, and social-ecological system dynamics in dryland ecosystems.
- Study science-based solutions on dryland ecosystem management and sustainable livelihood.
Main components of the dryland SES include: dryland ecosystem dynamics and driving forces, dryland ecosystem structure and functions, dryland ecosystem series, human well-being, and sustainable livelihoods. Essential dryland variables, which should ideally encompass both social and ecological aspects, will be meaningfully developed and used to measure each component of dryland SES. Such an interdisciplinary and integrative approach of ecology and sociology will offer a better understanding of and synergetic solutions to the impacts of these drivers on drylands.
Regional efforts will be carried out to capture the local nuance of climate impacts and particular response strategies of specific social-ecological system characteristics in different regions of the globe. Implementation of the coordinated international effort will be undertaken through various regional coordination nodes in Asia, Africa, Australia, and the Americas.
The Global Dryland Ecosystem Program (Global-DEP) was presented at the 2019 4th GLP Open Science Meeting held in Bern, Switzerland. Discussion following the presentation highlighted the synergies of this coordinated research effort and other ongoing GLP activities, especially in areas such as Central Asia and Africa. Additional comments included the importance of highlighting ecosystem process changes that may further challenge meeting sustainability goals.
Further information can be found at:
- Global Dryland Ecosystem Program Secretariat: firstname.lastname@example.org
- http://www.unep-iemp.org/index.php?menu=12 & id=161
Co-chairs: Prof. Bojie Fu (RCEES, CAS) and Dr. Mark Stafford Smith (CSIRO)