Abstract
The terrestrial biosphere has now been almost completely transformed by
human populations and their use of land. Here we map and characterize
anthropogenic transformation of the terrestrial biosphere from 1700 to
2000 using a rule-based anthrome (anthropogenic biome) classification
model applied to gridded global data for human population density and
land use. Anthropogenic transformation of terrestrial biomes into
anthromes was then characterized by map comparisons at century
intervals. This analysis reveals that between 1700 and 2000, the
terrestrial biosphere made the critical transition from mostly wild to
mostly anthropogenic, passing the 50% mark early in the 20th century. In
1700, nearly half of the terrestrial biosphere was wild, without human
settlements or substantial land use. Most of the remainder was in a
Seminatural state (45%) having only minor use for agriculture and
settlements. By 2000, the opposite was true, with the majority of the
biosphere in agricultural and settled anthromes, less than 20%
Seminatural and only a quarter left wild. Anthropogenic transformation
of the biosphere during the Industrial Revolution resulted about equally
from land use expansion into Wildlands and land use intensification
within Seminatural anthromes. Transformation pathways differed strongly
between biomes and regions, with some remaining mostly wild but with the
majority almost completely transformed into Rangelands, Croplands and
Villages. In the process of transforming almost 39% of Earth's total
ice-free surface into agriculture and settlements, an additional 37%
without such use have become embedded within agricultural and settled
anthromes. At present and ever more in the future, terrestrial ecosystem
form and process in most biomes will be predominantly anthropogenic, the
product of land use and other direct human interactions with ecosystems.
Earth science and ecological research and conservation efforts in all
but a few biomes would benefit from a primary focus on the novel
remnant, recovering and managed ecosystems embedded within used lands.
Historical analysis of global transitions between wild and anthropogenic
biomes provides a simple framework for assessing and modeling both past
and future global biotic and ecological patterns based on the form,
extent, duration, and intensity of their modification by humans.
Original language | English |
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Pages | 682 |
Publication status | Published - 1 Dec 2009 |
Externally published | Yes |
Keywords
- [0439] BIOGEOSCIENCES / Ecosystems
- structure and dynamics
- [1622] GLOBAL CHANGE / Earth system modeling
- [1630] GLOBAL CHANGE / Impacts of global change
- [1632] GLOBAL CHANGE / Land cover change