Agricultural Conservation Practices and Aquatic Ecological Responses

Richard E Lizotte,Peter C Smiley,Scott S Knight,Robert B Gillespie

doi:10.3390/w13121687

Abstract

Conservation agriculture practices (CAs) have been internationally promoted and used for decades to enhance soil health and mitigate soil loss. An additional benefit of CAs has been mitigation of agricultural runoff impacts on aquatic ecosystems. Countries across the globe have agricultural agencies that provide programs for farmers to implement a variety of CAs. Increasingly there is a need to demonstrate that CAs can provide ecological improvements in aquatic ecosystems. Growing global concerns of lost habitat, biodiversity, and ecosystem services, increased eutrophication and associated harmful algal blooms are expected to intensify with increasing global populations and changing climate. We conducted a literature review identifying 88 studies linking CAs to aquatic ecological responses since 2000. Most studies were conducted in North America (78%), primarily the United States (73%), within the framework of the USDA Conservation Effects Assessment Project. Identified studies most frequently documented macroinvertebrate (31%), fish (28%), and algal (20%) responses to riparian (29%), wetland (18%), or combinations (32%) of CAs and/or responses to eutrophication (27%) and pesticide contamination (23%). Notable research gaps include better understanding of biogeochemistry with CAs, quantitative links between varying CAs and ecological responses, and linkages of CAs with aquatic ecosystem structure and function.

Highlights

Identification and collection of studies reported globally in this synthesis included Identification andarticles collection studiesreviewed reportedbook globally in thisgovernment synthesis included peer-reviewed journal and of non-peer chapters, reports, peer-reviewed journal articles and non-peer reviewed book chapters, government restudent graduate theses, and proceedings papers published from years 2000–2020
Because the focus of the synthesis is on aquatic ecosystems, initial keyword and Because the focus of the synthesis is on aquatic ecosystems, initial keyword syntax used for the literature search included this focus: stream, river, lake, and pond
2000–2020 delineated that research aquatic tice, ecological structure, function, the ecological response to CAson

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Proper management of water resources including water quality and water quantity in agricultural watersheds is a key component to maintaining healthy aquatic ecosystems. Healthy aquatic ecosystems are sustainable ecosystems that exhibit resilience in their structure (i.e., biodiversity) and function (i.e., organic matter processing) in response to external stress [1] and subsequently able to provide a variety of ecosystem services including clean water, climate regulation, habitat for plants and animals, nutrient cycling, and productivity [2,3,4]. Ecosystem management approaches that focus on maximizing one ecosystem service result in declines of biodiversity and other ecosystem services [5]

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Results