Sediment Delivery to Sustain the Ganges-Brahmaputra Delta Under Climate Change and Anthropogenic Impacts

The principal nature-based solution for offsetting relative sea-level rise in the Ganges-Brahmaputra delta is the unabated delivery, dispersal, and deposition of the rivers’ ~1 billion-tonne annual sediment load. Recent hydrological transport modeling suggests that strengthening monsoon precipitation in the 21st century could increase this sediment delivery 34-60%; yet other studies demonstrate that sediment could decline 15-80% if planned dams and river diversions are fully implemented. We validate these modeled ranges by developing a comprehensive field-based sediment budget that quantifies the supply of Ganges-Brahmaputra river sediment under varying Holocene climate conditions. Our data reveal natural responses in sediment supply comparable to previously modeled results and suggest that increased sediment delivery may be capable of offsetting accelerated sea-level rise. This prospect for a naturally sustained Ganges-Brahmaputra delta presents possibilities beyond the dystopian future often posed for this system, but the implementation of currently proposed dams and diversions would preclude such opportunities

Developing Sources of Native Grass Seed for Revegetation in Florida

On the Ground • As with much of the eastern United States, the native plant communities present in Florida when European settlers arrived have been converted to cropland, pastureland, and industrial forest production. • Increasingly, both public and private entities have been making efforts to restore some of the converted acreage to a semblance of the original plant community for reasons of water quality, wildlife habitat, and aesthetics. • The lack of a commercial source of seed for Florida ecotypes of native grasses is one of the main costs associated with current revegetation efforts. • A long-term program, by the USDA, NRCS, Brooksville Plant Materials Center and various cooperating public and private institutions, has fostered the development of a commercial, native grass-seed industry in the state.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202