Biology subjects

Grantham, H. S.

Publications and source records attributed to Grantham, H. S..

3 recordsLinked to original sources

bioRxiv2020

Change in terrestrial human footprint drives continued loss of intact ecosystems

Our ability to map humanitys influence across Earth has evolved, thanks to powerful computing, a network of earth observing satellites, and new bottom-up census and crowd-sourced data. Here, we provide the latest temporally inter-comparable maps of the terrestrial Human Footprint, and assessment of change in human pressure at global, biome, and ecoregional scales. In 2013, 42% of terrestrial Earth could be considered relatively free of anthropogenic disturbance, and 25% could be classed as wilderness (the least degraded end of the human footprint spectrum). Between 2000 and 2013, 1.9 million km2 - an area the size of Mexico - of land relatively free of human disturbance became highly modified. The majority of this occurred within tropical and subtropical grasslands, savannah, and shrubland ecosystems, but the rainforests of Southeast Asia also underwent rapid modification. Our results show that humanitys footprint is eroding Earths last intact ecosystems, and greater efforts are urgently needed to retain them.

ecology↗

bioRxiv2020

Only 40% of the world's forests are in good health

Many global environmental agendas, including halting biodiversity loss, reversing land degradation, and limiting climate change, depend upon retaining forests with high ecological integrity, yet the scale and degree of forest modification remains poorly quantified and mapped. By integrating data on observed and inferred human pressures and an index of lost connectivity, we generate the first globally-consistent, continuous index of forest condition as determined by degree of anthropogenic modification. Globally, only 17.4 million km2 of forest (40.5%) have high landscape level integrity (mostly found in Canada, Russia, the Amazon, Central Africa and New Guinea) and only 27% of this area is found in nationally-designated protected areas. Of the forest in protected areas, only 56% has high landscape level integrity. Ambitious policies that prioritize the retention of forest integrity, especially in the most intact areas, are now urgently needed alongside current efforts aimed at halting deforestation and restoring the integrity of forests globally.

ecology↗

bioRxiv2019

Area requirements to safeguard Earth’s marine species

Despite global policy commitments to preserve Earths marine biodiversity, many species are in a state of decline. Using data on 22,885 marine species, we identify 8.5 million km2 of priority areas that complement existing areas of conservation and biodiversity importance. New conservation priorities are found in over half (56%) of all coastal nations, with key priority regions in the northwest Pacific Ocean and Atlantic Ocean. We identify where different conservation actions, ranging from marine protected areas to broader policy approaches, may best overcome anthropogenic threats to these areas. This analysis shows 26-41% of the ocean (depending on targets used for species representation) needs to be effectively conserved through a combination of site-based actions and wider policy responses to achieve global conservation and sustainable development agendas.\n\nOne Sentence SummaryAt least 26% of the ocean needs a combination of site-based conservation and wider policy responses to achieve global conservation goals.

ecology↗