DOI: 10.5061/dryad.jm63xsjn0
title: Data from: Addressing grand ecological challenges in aquatic ecosystems: How can mesocosms be used to advance solutions?

description: Rapid and drastic anthropogenic impacts are affecting global
 biogeochemical processes and driving biodiversity loss across Earth’s
 ecosystems. In aquatic ecosystems, species distributions are shifting,
 abundances of many species have declined dramatically, and many are
 threatened with extinction. In addition to loss of diversity, the
 ecosystem functions, processes and services on which humans depend are
 also being heavily impacted. Addressing these challenges not only requires
 direct action to mitigate environmental impacts but also innovative
 approaches to identify, quantify and treat their effects in the
 environment. Mesocosms are valuable tools for achieving these goals as
 they provide controlled environments for evaluating effects of stressors
 and testing novel mitigation measures at multiple levels of biological
 organisation. Here, we summarise discussions from a survey of marine and
 freshwater researchers who use mesocosm systems to synthesise their
 opportunities and limitations for advancing solutions to grand ecological
 challenges in aquatic ecosystems. While most research utilising mesocosm
 systems in aquatic ecology has focused on quantifying the effects of
 environmental threats, there is a largely unexplored potential for using
 them to test solutions. To overcome spatio-temporal constraints, there are
 opportunities to scale up the size and time-scales of mesocosm studies, or
 alternatively, test the outcomes of habitat-scale restoration at a smaller
 scale. Enhancing connectivity in future studies can help to overcome the
 limitation of isolation and test an important aspect of ecological
 recovery. Conducting ‘metacosm’ studies: co-ordinated, distributed
 mesocosm experiments spanning wide climatic and environmental gradients
 and utilising more regression-based experimental designs can help to
 tackle the challenge of context dependent results. Finally, collaboration
 of theoretical, experimental and applied ecologists and biogeochemists
 with environmental engineers and technological developers will be
 necessary to develop and test the tools required to advance solutions to
 the impacts of human activities on Earth’s vulnerable aquatic ecosystems.
description: A survey titled “<em>Mesocosms as a tool to address grand
 challenges: current research and future opportunities in aquatic
 ecology”</em> was designed using the SurveyMonkey online
 survey-building platform and was tested and adapted based on test feedback
 prior to distribution. Distribution of the survey was primarily achieved
 via email and social media platforms. The survey link was also advertised
 on the aquacosm.eu home webpage. The survey was open for responses for
 five months from April 28th to September 31st, 2022. Survey participants
 were informed of the purpose of the study, the method for gathering data,
 the use(s) of gathered data and the process of data storage. All
 contributors consented to participating in the survey according to these
 ethical guidelines and the use of gathered data in publication.
 Participant data was stored in compliance with GDPR. A
 diverse group of researchers across different aquatic ecosystems was
 targeted, including both freshwater and marine environments to foster
 cross-system perspectives. While responses were welcomed from researchers
 regardless of their prior use of mesocosms, the majority of respondents
 were, understandably (given the survey topic), those with direct
 experience using mesocosm systems in their work. The potential sampling
 and response bias in our approach is acknowledged, as respondents were
 likely to be proponents of mesocosm research, particularly if they were
 active users of mesocosms. This is an inherent limitation of our approach,
 however, advantages of the survey approach were that it enabled gathering
 information not yet available in the published literature and informed
 insights and perspectives from experts with extensive hands-on knowledge,
 who are best positioned to identify the practical applications and
 limitations of these systems. There were two central
 questions in the survey used to gather information about the utility of
 aquatic mesocosm systems for addressing grand ecological challenges and to
 understand perspectives of how they could be used in future
 solution-focused research: <strong>1.     
 </strong><strong>Which grand ecological challenges has your
 aquatic ecology research already addressed (with the mesocosm system you
 have used most)?</strong> o   Please select a
 weight from 1 (none) to 4 (mostly in this area) indicating how much
 research has been done in each area below. o   Note
 that some of these may be sub-categories of each other (in which case you
 can tick research in both) and there is also an opportunity to suggest
 additional challenges in each category (environmental threats and
 solution-focused research topics).
 <strong>2.      </strong><strong>Which grand
 challenges do you think your system could be used to address in the
 future?</strong> o   Please select a weight from
 1 (no potential) to 5 (very strong potential) indicating the potential for
 this system to address the grand challenges listed. For those that you
 rank good or very strong potential (4-5), please provide a brief
 indication with relevant details why in the comment box at the bottom of
 the page. o   Note there is also an opportunity to
 provide additional challenges in each category.
description: # Addressing grand ecological challenges in aquatic ecosystems: How can
 mesocosms be used to advance solutions?
 [https://doi.org/10.5061/dryad.jm63xsjn0](https://doi.org/10.5061/dryad.jm63xsjn0) ## Description of the data and file structure ### Files and variables #### File: Survey\_responses\_collated\_data.xlsx **Description:** Response data collated for the survey; “*Mesocosms as a tool to address grand challenges: current research and future opportunities in aquatic ecology”* ##### Variables * Applied research category (either *Environmental threat* or *Solution*). * Environmental threat or solution topic (i.e. "grand challenge") * Aquatic system (*Still freshwater, Running freshwater,* or* Marine*). * Responses (number of responses) * Skipped (number of respondents who skipped this answer (but provided demographic information, etc.)) * 1\. No research in this area (percentage of respondents who selected this weighting to indicate how much research has been done in each topic ("grand challenge") using their mesocosm system) * 2\. A little research in this area (percentage of respondents who selected this weighting to indicate how much research has been done in each topic ("grand challenge") using their mesocosm system) * 3\. A lot of research in this area (percentage of respondents who selected this weighting to indicate how much research has been done in each topic ("grand challenge") using their mesocosm system) * 4\. Most research in this system is in this area (percentage of respondents who selected this weighting to indicate how much research has been done in each topic ("grand challenge") using their mesocosm system) * 1\. No potential (percentage of respondents who selected this weighting to indicate the potential for their mesocosm system to address each research topic/grand challenge) * 2\. Some, but limited potential (percentage of respondents who selected this weighting to indicate the potential for their mesocosm system to address each research topic/grand challenge) * 3\. Medium potential (percentage of respondents who selected this weighting to indicate the potential for their mesocosm system to address each research topic/grand challenge) * 4\. Good potential (percentage of respondents who selected this weighting to indicate the potential for their mesocosm system to address each research topic/grand challenge) * 5\. Very strong potential (percentage of respondents who selected this weighting to indicate the potential for their mesocosm system to address each research topic/grand challenge) "NA" indicate no responses because this category was missing from this question in the survey. "-" indicates responses are not relevant for this category in this system, as determined by co-authors (not that there is a reponse of zero percent).