Using historical ecology to understand patterns of biodiversity in fragmented agricultural landscapes

Abstract

Aim To enhance current attempts to understand biodiversity patterns by using an historical ecology approach to highlight the over‐riding influence of land‐use history in creating past, current and future patterns of biodiversity in fragmented agricultural landscapes. Methods We develop an integrative conceptual framework for understanding spatial and temporal variations in landscape patterns in fragmented agricultural landscapes by presenting five postulates (hypotheses) which highlight the important role of historical, anthropogenic disturbance regimes. We then illustrate each of these postulates with examples drawn from fragmented woodlands in agricultural areas of south‐eastern Australia, and discuss these findings in an international context. Location examples are drawn from agricultural areas in south‐eastern Australia. Results We conclude that there is limited potential to refine our understanding of patterns of biodiversity in human‐modified landscapes based on traditional concepts of island biogeography, or simple assumptions of ongoing destruction and degradation. Instead, we propose that in agricultural landscapes that were largely cleared over a century ago: (1) present‐day remnant vegetation patterns are not accidental, but are logically arrayed due to historic land‐use decisions, (2) historic anthropogenic disturbances have a major influence on current ecosystem conditions and diversity patterns, and (3) the condition of remnant ecosystems is not necessarily deteriorating rapidly. Main conclusions An historical ecology approach can enhance our understanding of why different species and ecosystem states occur where they do, and can explain internal variations in ecological conditions within remnant ecosystems, too often casually attributed to the ‘mess of history’. This framework emphasizes temporal changes (both past and future) in biotic patterns and processes in fragmented agricultural landscapes. Integration of spatially and temporally explicit historical land‐use information into ecological studies can prove extremely useful to test hypotheses of the effects of changes in landscape processes, and to enhance future research, restoration and conservation management activities.

Vegetation of a tropical dry forest in a landscape with chronic disturbance: the case of the indigenous community of San Nicolás Zoyatlan (Guerrero, Mexico)

“…While it might be expected that they could be evident in Zoyatlan due to fragmentation and chronic disturbance over more than five centuries, this was not conclusive because there are still many features in the vegetation that characterize the TDFs of the Balsas basin. The dynamics of vegetation regeneration, which has its best expression in fragments less suitable for the development of agriculture due to their inaccessibility was also evident; this suggests that agriculture and grazing has not exceed the threshold that would prevent the dynamics and reorganization of the socio-ecological system (Lunt & Spooner 2005, Cramer & Hobbs 2007. According to land use in 1998 (Cervantes et al 2014) and the results of this research, the fragments with U-2, U-3 and U-4 are represented in nearly 600 ha.…”

Andean Land Use and Biodiversity: Humanized Landscapes in a Time of Change

“…The continued persistence of native species in these landscapes may depend as much on the patterns and dynamics of landscape mosaics as on species characteristics themselves (Danielson, 1991;Ovaskainen et al, 2002). Knowledge of current mosaic patterns, land-use change, and historical legacies will permit better understanding of landscape processes and possible conservation goals (Lunt & Spooner, 2005). For example, the carbon found in Andean fields will have value for carbon sequestration payments (Antle et al, 2007), giving additional conservation reasons for working with agricultural landscapes.…”

Why are woodland-dependent avian insectivore populations vulnerable to declines in highly-modified landscapes?

“…In the past, farmers preferentially cleared woodlands that grew on the most productive soils or that were located near a reliable water source (Fensham and Fairfax 2003;Lunt and Spooner 2005;Watson 2011;Simmonds et al 2017).…”