Human-nature interactions in the Chambal Badlands, India: geomorphological perspectives on the dual challenges of land degradation and geoheritage promotion

In many drylands globally, badlands (coalesced gully networks) have developed in colluvial (e.g. hillslope, pediment) and alluvial (e.g. river terrace, floodplain) landforms.  Badland development can have serious on-site and off-site impacts including soil loss and reservoir sedimentation but can also create striking visual scenery that may have aesthetic appeal and geoheritage potential.  Vigorous debate surrounds the relative importance of human and natural factors in badland development, with some researchers attributing their development mainly to human causes such as poor land management, while others have argued for natural causes, including decadal-scale climatic fluctuations, susceptible soil characteristics, and/or breaching of hard rock barriers along river beds.  Intrinsic land surface adjustments may also account for some gullies, such as valley floor oversteepening that leads to erosion and slope adjustment.  In short, is badland development dominantly a human-induced problem, a natural part of landscape development, or some combination of both factors? The answer has implications not only for advancing our understanding of Earth surface dynamics and human–nature interactions, but also for the targeting of the limited resources aimed at erosion control, sustainable land management, and geoheritage promotion.

 

The Chambal Badlands in semiarid, north-central India exemplify these issues.  The ~4800 km² badlands are some of the largest in the world and present striking development challenges: soil erosion threatens food and water security but the deeply dissected terrain provides opportunities for geoheritage promotion.  The region faces intertwined socio-economic and environmental challenges: marginal agriculture, limited alternative livelihoods, and widespread soil loss. In places, the badlands are heavily degraded by poorly controlled agricultural developments. Attempts to infill gullies and level the land for cultivation often fail within years as the soil simply re-erodes, trapping farmers in never-ending cycles of nutrient, water and soil carbon loss.  At the same time, the badlands and associated bedrock channels, potholes, waterfalls and gorges of the Chambal and other nearby rivers illustrate landform combinations rarely present elsewhere on Earth, and certainly not at the same scale, and their promotion as geoheritage could enhance geoeducation (e.g. for local schools) and geotourism (e.g. for domestic/international markets).

 

We report here on the initial findings from a UK-India collaborative project that is combining field data, laboratory analyses and science communication to address key questions, including: i) when and why did the badlands form?; ii) do modern agricultural practices enhance badland growth?; iii) how can we best use this information to address the development challenges?  Geomorphological perspectives are a crucial element of the project, which hopes to develop a scientific, practical, and social blueprint for transforming the fragile badlands into productive and culturally-valued, resilient landscapes.