Landscape-wide changes in land use and land cover correlate with, but rarely explain local biodiversity change

Martin Jung,Pedram Rowhani,Jörn P. W. Scharlemann

doi:10.1007/s10980-020-01109-2

Abstract

ContextThere is an ongoing debate whether local biodiversity is declining and what might drive this change. Changes in land use and land cover (LULC) are suspected to impact local biodiversity. However, there is little evidence for LULC changes beyond the local scale to affect biodiversity across multiple functional groups of species, thus limiting our understanding of the causes of biodiversity change.ObjectivesHere we investigate whether landscape-wide changes in LULC, defined as either trends in or abrupt changes in magnitude of photosynthetic activity, are driving bird diversity change.MethodsLinking 34 year (1984–2017) time series at 2745 breeding bird survey (BBS) routes across the conterminous United States of America with remotely-sensed Landsat imagery, we assessed for each year what proportion of the landscape surrounding each BBS route changed in photosynthetic activity and tested whether such concomitant or preceding landscape-wide changes explained changes in bird diversity, quantified as relative abundance (geometric mean) and assemblage composition (Bray–Curtis index).ResultsWe found that changes in relative abundance was negatively, and assemblage composition positively, correlated with changes in photosynthetic activity within the wider landscape. Furthermore, landscape-wide changes in LULC in preceding years explained on average more variation in bird diversity change than concomitant change. Overall, landscape-wide changes in LULC failed to explain most of the variation in bird diversity change for most BBS routes regardless whether differentiated by functional groups or ecoregions.ConclusionsOur analyses highlight the influence of preceding and concomitant landscape-wide changes in LULC on biodiversity.

Highlights

Ongoing human alteration of the Earth surface causes changes in biodiversity across scales (Gibson et al 2011; Murphy and Romanuk 2014; Newbold et al 2015)
Across all breeding bird survey (BBS) routes the geometric mean of relative bird abundances (GM) increased by 0.01% ± 0.002 standard error (SE) per year in the first two decades from 1984 to 2005, after which annual decreases of 0.01% ± 0.003 SE were observed (Fig. S5a)
Across all BBS routes the mean proportion of land with an abrupt change in the magnitude of EVI fluctuated strongly (Fig. S8a), while the mean proportion of grid cells showing a trend in EVI showed an inverse hump-shaped pattern for greening and a continuous decrease for browning (Fig. S8b)

Summary

Introduction

Ongoing human alteration of the Earth surface causes changes in biodiversity across scales (Gibson et al 2011; Murphy and Romanuk 2014; Newbold et al 2015). Several global meta-analyses have demonstrated that some biodiversity measures, notably species richness, have not declined at local scales, e.g. the scale of biodiversity sampling (Vellend et al 2013, 2017; Dornelas et al 2014) These results have been questioned, whether the data are spatially and temporally biased (Gonzalez et al 2016) or whether sites with and without land change were differentiated (Cardinale et al 2018). Changes in land use and land cover (LULC) have been identified as one of the dominant driver of terrestrial biodiversity loss (Dıaz et al 2019) This raises the question whether such changes on land can explain changes in local biodiversity measures across space and time

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Conclusion