Nature, Culture, and Conservation in the Anthropocene - Biodiversity Conservation and Environmental Change - page 146

largely abandoned in the tenth century ce, and coastal foci thrived during the post-classic
period (900-1500 ce) (Van der Leeuw et al. 2011).
The final political collapse of Maya society occurred in a century-long drought beginning
in 1020 ce, during the Medieval Warm Period. Though rainfall increased again during the Lit-
tle Ice Age, and forest cover of the elevated interior region recovered in less than three centu-
ries, the human population never returned. By then, the elaborate systems of reservoirs had
fallen into disrepair, and the reconstruction of these was thought to be a major barrier to
reoccupation of the highlands. The abandoned cities, reclaimed by the forest, would also
have been regarded as dangerous, disordered places that bore witness to the failure of once
revered leaders, and were now occupied by ill fortune and malevolent spirits (Kennett et al.
2012, Dunning et al. 2012, Turner and Sabloff 2012).
The cycles of building, collapse, and reorganization reflect the interplay between societal
adaptation and environment. Rainfall, water quality and availability, trade opportunities,
and exposure to hazards varied on moving from the coastal lowland to the elevated interior
regions, and people responded by developing livelihood strategies appropriate to climate,
environment, and local opportunities. The elevated interior region was more sensitive to
rainfall seasonality because there are few areas of permanent water, whereas the lowlands
had perennial springs and swamps. However, the lowlands were more vulnerable to hurri-
canes, forest fires, and sea-level rise (Figure 7.2c). Trade opportunities shifted from interior to
coastal areas as maritime trade routes developed. Thus, it was the interplay between hazard,
environmental innovation and degradation, and trade opportunities that drove population
flux and the spatially and temporally complex patterns of growth and abandonment in differ-
ent areas of the peninsula.
Understanding the linkages between environmental change and socioecological systems
requires an integrated approach that accommodates complex webs of interacting factors at a
range of spatial and temporal scales (Costanza et al. 2007, Van der Leeuw et al. 2011). The Inte-
grated History and future of People on Earth (IHOPE) initiative is a global research network that
links past, present, and future through integrated, cross-scale analysis of biophysical and social
change from the humanities and the biophysical and social sciences (<http://ihopenet.org/>).
The aim is to map and understand socioecological change over the past several millennia, then
to use this information to test the reliability of human-environment models, which can in turn
be made to explore the options for sustainable socio-ecological dynamics in the future (Cos-
tanza et al. 2007, Van der Leeuw et al. 2011). Heckbert (2013) used a dynamic systems model to
simulate the Maya civilization as a linked socio-ecological system. MayaSim includes demo-
graphics, settlements, trade, agriculture, technology, and institutions, alongside environmental
variables like soil degradation, provision of ecosystem services, climate variability, hydrology,
primary productivity, and forest succession. Interactions between agents and networks play
out over a spatial grid of cells, allowing patterns to emerge at the landscape level as resources,
climate, and other variables change over time (Figure 7.3). The model simulates the dynamics
of the system over three major drought periods, showing how rainfall, changes in agricultural
potential and other ecosystem services, and trade networks affect settlement patterns.
The model approximate the Preclassic Classic, Classic, and Postclassic periods, and shows