Contents lists available at ScienceDirect Ecological Indicators journal homepage: www.elsevier.com/locate/ecolind Original Articles Effects of riverine landscape changes on pollination services: A case study on the River Minho, Portugal Artur Santos, Maria Rosário Fernandes ⁎ , Francisca C. Aguiar, Manuela R. Branco, M. Teresa Ferreira Forest Research Centre (CEF), School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisboa, Portugal ARTICLE INFO Keywords: Historical cartography LULC change Riverscapes Insect pollination Ecosystem services Pollination Suitability Index ABSTRACT Riverine landscapes provide numerous ecosystem services, of which pollination is essential to increase the yield, quality, and stability of crops and the biodiversity of wild flora. Pollinators’ behaviour and their community dynamics are often affected by the spatial distribution of floral and nesting resources at the landscape scale, and are thus sensitive to land-use land-cover (LULC) changes and management practices. The main objective of this study is to understand how changes in riparian vegetation and LULC at River Minho affect pollination services. For this, an approach based on the temporal analysis of historical cartography (1898) and current satellite imagery (2016) was used. We developed a novel Pollination Suitability Index for Riverine Landscapes (PSIRL) using LULC data as a proxy of habitat suitability for insect pollinators. PSIRL scores were derived from expert judgment of the local habitat conditions, floral diversity and field surveys. The PSIRL values obtained for both periods were compared using pairwise T-tests. We detected an overall reduction of the pollination services in the riverine landscape of River Minho from 1898 to 2016. However, at local level we observed gains and losses of pollination suitability as a result of distinct LULC changes. There was a marked decrease in the PSIRL in the most downstream and upstream riverine sec- tions due to generalized conversion of scrublands, broadleaved-forests and heterogeneous agricultural areas to artificial surfaces and managed forests dominated by maritime pine and eucalyptus. However, in the middle section of the river, the area occupied by scrublands, riparian and broadleaved forests increased, resulting in an increase of the foraging resources for insects, and a consequent increase of the PSIRL. This index can be used to monitor and capture changes in the pollination suitability of complex riverine landscapes and support further land and river management decisions. The historical cartography proved to be a valuable source of information to characterize LULC change and hence to assess the evolutionary trajectory of pollination ecosystem services, at global and local level. 1. Introduction Pollination is an essential ecosystem service that increases the yield, quality, and stability of 75% of globally important crops (Klein et al., 2007) and safeguards the conservation of wild plant populations (Potts et al., 2010). Social bees (Hymenoptera: Apidae) are generally regarded as the most important insect pollinators. In particular, the European honeybee (Apis mellifera L.) is considered responsible for 80% of the global agri- cultural pollination services (Carreck and Williams, 1998). Recently, the dominance of honeybees in providing crop pollination services has been questioned (Breeze et al., 2011; Rader et al., 2016). In fact, several studies have shown that wild pollinators such as the solitary bees, hoverflies, bee flies, butterflies, moths, some beetles and some wasps also provide important pollination services (e.g. Garibaldi et al., 2013; Rader et al., 2016). Their individual behaviour, population biology, and community dynamics are affected by the spatial distribution of floral resources at the landscape scale (Kremen et al., 2007). A widespread concern about the health of ecosystems in Europe brought attention to the vulnerability of pollinator species (Potts et al., 2010; Breeze et al., 2014). Several European countries are presently vulnerable to polli- nation declines. For example, in the UK, during the last 50 years there has been considerable reduction in the diversity and distribution of wild bees, butterflies and hoverflies (Thomas et al., 2004; Biesmeijer et al., 2006; Carvell et al., 2006). The intensification of agricultural and urban land-use and the consequent loss and fragmentation of natural habitats https://doi.org/10.1016/j.ecolind.2018.02.036 Received 2 November 2017; Received in revised form 14 February 2018; Accepted 16 February 2018 ⁎ Corresponding author. E-mail addresses: mrfernandes@isa.ulisboa.pt (M.R. Fernandes), fraguiar@isa.ulisboa.pt (F.C. Aguiar), mrbranco@isa.ulisboa.pt (M.R. Branco), terferreira@isa.ulisboa.pt (M.T. Ferreira). Ecological Indicators 89 (2018) 656–666 1470-160X/ © 2018 Elsevier Ltd. All rights reserved. T