@article{17f5048f9be14d56ae4c0ffc5057c73f,
title = "Multi-scale assessment of human-induced changes to Amazonian instream habitats",
abstract = "Context: Land use change and forest degradation have myriad effects on tropical ecosystems. Yet their consequences for low-order streams remain very poorly understood, including in the world´s largest freshwater basin, the Amazon. Objectives: Determine the degree to which physical and chemical characteristics of the instream habitat of low-order Amazonian streams change in response to past local- and catchment-level anthropogenic disturbances. Methods: To do so, we collected field instream habitat (i.e., physical habitat and water quality) and landscape data from 99 stream sites in two eastern Brazilian Amazon regions. We used random forest regression trees to assess the relative importance of different predictor variables in determining changes in instream habitat response variables. Results: Multiple drivers, operating at multiple spatial scales, were important in determining changes in the physical habitat and water quality of the sites. Although we found few similarities in modelled relationships between the two regions, we observed non-linear responses of specific instream characteristics to landscape change; for example 20 % of catchment deforestation resulted in consistently warmer streams. Conclusions: Our results highlight the importance of local riparian and catchment-scale forest cover in shaping instream physical environments, but also underscore the importance of other land use changes and activities, such as road crossings and upstream agriculture intensification. In contrast to the property-scale focus of the Brazilian Forest code, which governs environmental regulations on private land, our results reinforce the importance of catchment-wide management strategies to protect stream ecosystem integrity.",
keywords = "Amazon basin, Anthropogenic impacts, Deforestation, Freshwater, Land use change, Physical and chemical habitat, Random forest models, Tropical forest, Watershed management",
author = "Cecilia Leal and Paulo Pompeu and Toby Gardner and Rafael Leit{\~a}o and Robert Hughes and Phil Kaufmann and Jansen Zuanon and {de Paula}, Felipe and Silvio Ferraz and {MAC NALLY}, Ralph and Joice Ferreira and Jos Barlow",
note = "Funding Information: We dedicate this paper to Manoel Nascimento (aka “Nego”) for his invaluable work as a field technician and naturalist. We thank Ceceo Chaves, D{\'e}bora de Carvalho, Douglas Bastos, Elbin da Silva, Francisco Cunha (“Pita”), Jana{\'i}na de Brito, Jos{\'e} Max de Oliveira-Silva, Karina Silva, Leandro Brasil, Leandro Juen, Lenise Flores, Lucas Pires, Marcos Vin{\'i}cius da Silva, Martinez de Oliveira, M{\'i}riam de Almeida, Rafael Duarte, Renilson de Freitas (“Graveto”), T{\'u}lio Franco, Valderir Nascimento, and Vivian de Oliveira for their assistance in the field work and the farmers and workers unions of Santar{\'e}m, Belterra, and Paragominas and all collaborating private landowners for their support. We are also grateful for financial support from Instituto Nacional de Ci{\^e}ncia e Tecnologia—Biodiversidade e Uso da Terra na Amaz{\^o}nia (CNPq; 574008/2008-0), Empresa Brasileira de Pesquisa Agropecu{\'a}ria (Embrapa; SEG: 02.08.06.005.00), the UK government Darwin Initiative (17-023), The Nature Conservancy, Natural Environment Research Council (NERC; NE/F01614X/1 and NE/G000816/1), and Fulbright Brasil. Individual funding included a Coordena{\c c}{\~a}o de Aperfei{\c c}oamento de Pessoal de N{\'i}vel Superiror (CAPES) scholarship in Brazil and a Science without Borders Grant in the United Kingdom (PDSE-2943/13-1) to CGL; a CNPq (304002/2014-3) and a FAPEMIG (PPM-00608/15) research fellowship to PSP; CNPq (#156915/2011-1) and CAPES Science Without Borders Grant in France (PDSE-1914/13-8) to RPL, and a CNPq Award (400640/2012-0) to JB. Our manuscript benefitted greatly from reviews by Dr. P{\'e}ter S{\'a}ly, Dr. Ryan Hill, and two anonymous reviewers. It was subjected to review by the U.S. Environmental Protection Agency National Health and Environmental Effects Research Laboratory{\textquoteright}s Western Ecology Division and approved for publication. Approval does not signify that the contents reflect the views of the Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. This paper is #47 in the Sustainable Amazon Network ( http://www.redeamazoniasustentavel.org/ ) and #43 in Projeto Igarap{\'e}s ( http://www.igarapes.bio.br ) publication series. Publisher Copyright: {\textcopyright} 2016, The Author(s).",
year = "2016",
month = oct,
day = "1",
doi = "10.1007/s10980-016-0358-x",
language = "English",
volume = "31",
pages = "1725--1745",
journal = "Landscape Ecology",
issn = "0921-2973",
publisher = "Springer",
number = "8",
}