Heike K. Lotze

Heike K. Lotze
Dalhousie University | Dal · Department of Biology

PhD

About

222
Publications
100,610
Reads
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23,673
Citations
Introduction
Heike K. Lotze currently works at the Department of Biology, Dalhousie University.
Additional affiliations
July 2003 - June 2005
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research
Position
  • Research Associate
June 1994 - December 1998
GEOMAR Helmholtz Centre for Ocean Research Kiel
Position
  • Research Associate
May 1994 - December 1998
Christian-Albrechts-Universität zu Kiel
Position
  • PhD Student

Publications

Publications (222)
Article
Full-text available
Cumulative human impact analysis is a promising management tool to estimate the impacts of stressors on ecosystems caused by multiple human activities. However, connecting cumulative impact scores to actual ecosystem change at appropriate spatial scales remains challenging. Here, we calculated cumulative effects (CE) scores for 187 seagrass beds in...
Article
Full-text available
Climate change and biodiversity loss are twin crises that are driving global marine conservation efforts. However, if unaccounted for, climate change can undermine the efficacy of such efforts. Despite this, integration of climate change adaptation and resilience into spatial marine conservation and management has been limited in Canada and elsewhe...
Article
Full-text available
Projections of climate change impacts on marine ecosystems have revealed long-term declines in global marine animal biomass and unevenly distributed impacts on fisheries. Here we apply an enhanced suite of global marine ecosystem models from the Fisheries and Marine Ecosystem Model Intercomparison Project (Fish-MIP), forced by new-generation Earth...
Article
Full-text available
Non-technical summary We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding about the remaining options to achieve the Paris Agreement goals, through overcoming political barriers to carbon pricing, taking into account non-CO 2 factors, a well-designed implem...
Article
Marine biodiversity is the essential foundation for the structure and functioning of ocean ecosystems and for providing the full range of ecosystem services that benefit humans on local, regional, and global scales. These benefits include many visible as well as unseen functions and services such as the oxygen we breathe, the seafood we eat, the su...
Article
Globally, lobsters are one of the most economically valuable wild species caught in capture fisheries. Catches are dominated by American lobster (Homarus americanus) landed entirely in Atlantic Canada and northeastern United States. In Atlantic Canada, lobster fishing and marine finfish aquaculture take place in the same coastal waters creating the...
Article
Climate change is altering ecosystems and fisheries throughout the world's oceans, demanding climate-adaptive governance for conserving and managing living marine resources. While in some regions fisheries management systems address wider ecosystem dynamics within management frameworks and decision-making, which may facilitate resilience to climate...
Article
Diatoms often dominate phytoplankton in temperate, polar and upwelling regions. Decreases in silicate availability or silicon to nitrogen (Si:N) ratios may induce silicon limitation in diatoms and lower their proportion within phytoplankton communities. The effects of such changes on the nutritional quality of phytoplankton are not well understood....
Article
Full-text available
A Correction to this paper has been published: https://doi.org/10.1038/s41586-021-03271-2.
Technical Report
Full-text available
Eelgrass (Zostera marina) meadows are influenced by human activities occurring at various spatial scales. We applied a standardized human impact metric previously applied to eelgrass in Atlantic Canada to ten eelgrass meadows in six bays in southern British Columbia to quantify the extent of human activities occurring at both the bayscale and local...
Article
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The United Nations Convention on Biological Diversity was established in 1993. Canada is a signatory nation that has adopted, and exceeded, the UN Aichi biodiversity target to protect 10% of coastal and marine areas through marine protected areas or “other effective area-based conservation measures” (OECMs) by 2020. However, the science of OECMs as...
Article
Full-text available
Our societies will change following the COVID-19 crisis, as well as ocean management. Here we present 10 action points in a marine context, to re-energize our economies and avert the biodiversity and climate change crises of which the present COVID-19 crisis represents a portend: (1) promote carbon neutral economies to mitigate global warming; (2)...
Article
Full-text available
Seagrass meadows are among the most productive and diverse marine ecosystems, providing essential structure, functions, and services. They are also among the most impacted by human activities and in urgent need of better management and protection. In Canada, eelgrass ( Zostera marina) meadows are found along the Atlantic, Pacific, and Arctic coasts...
Chapter
Ambient temperature is a leading environmental factor determining the distribution and diversity of life in the oceans. Hence, climate change is fundamentally changing marine biodiversity on a global scale and will continue to do so into the future. Here, we review observed and predicted effects of climate change on the diversity of marine species....
Chapter
Climate change is already influencing life in the ocean and will continue to do so into the future with consequences for fisheries and seafood production. Observed physical and chemical climate-change effects alter basic biological processes, such as the survival, growth, and reproduction of marine organisms, the distribution and abundance of targe...
Article
Full-text available
Despite decades of management and conservation efforts, we have seen only limited success in rebuilding marine life and restoring ocean ecosystems from human-inflicted damage on a global scale. I suggest that we need to harness both our emotional (love) and rational (knowledge) sides to create a more powerful movement to heal the ocean and rebuild...
Article
Full-text available
Considerable effort is being deployed to predict the impacts of climate change and anthropogenic activities on the ocean's biophysical environment, biodiversity, and natural resources to better understand how marine ecosystems and provided services to humans are likely to change and explore alternative pathways and options. We present an updated ve...
Article
Full-text available
Climate-induced changes in the world’s oceans will have implications for fisheries productivity and management. Using a model ensemble from the Fisheries and Marine Ecosystem Model Intercomparison Project (Fish-MIP), we analyzed future trajectories of climate-change impacts on marine animal biomass and associated environmental drivers across the No...
Preprint
Full-text available
A group of ocean experts brainstormed about the most pressing actions to be taken in favour of ocean conservation in the context of SARS-CoV2
Article
Many coastal oceans experience not only increased loads of nutrients but also changes in the stoichiometry of nutrient supply. Excess supply of nitrogen and stable or decreased supply of silicon lower silicon to nitrogen (Si:N) ratios, which may decrease diatom proportion in phytoplankton. To examine how Si:N ratios affect plankton community compos...
Article
Full-text available
Future climate impacts and their consequences are increasingly being explored using multi-model ensembles that average across individual model projections. Here we develop a statistical framework that integrates projections from coupled ecosystem and earth-system models to evaluate significance and uncertainty in marine animal biomass changes over...
Article
Sustainable Development Goal 14 of the United Nations aims to “conserve and sustainably use the oceans, seas and marine resources for sustainable development”. Achieving this goal will require rebuilding the marine life-support systems that deliver the many benefits that society receives from a healthy ocean. Here we document the recovery of marine...
Article
Climate change is increasingly impacting marine protected areas (MPAs) and MPA networks, yet adaptation strategies are rarely incorporated into MPA design and management plans according to the primary scientific literature. Here, we review the state of knowledge for adapting existing and future MPAs to climate change and synthesize case studies (n...
Article
Full-text available
Under climate change, species composition and abundances in high-latitude waters are expected to substantially reconfigure with consequences for trophic relationships and ecosystem services. Outcomes are challenging to project at national scales, despite their importance for management decisions. Using an ensemble of six global marine ecosystem mod...
Article
Full-text available
The impacts of climate change and the socioecological challenges they present are ubiquitous and increasingly severe. Practical efforts to operationalize climate-responsive design and management in the global network of marine protected areas (MPAs) are required to ensure long-term effectiveness for safeguarding marine biodiversity and ecosystem se...
Article
Harvesting wild seaweeds has a long history and is still relevant today, even though aquaculture now supplies >96% of global seaweed production. Current wild harvests mostly target canopy-forming kelp, rockweed and red macroalgae that provide important ecosystem roles, including primary production, carbon storage, nutrient cycling, habitat provisio...
Article
Eelgrass (Zostera marina) is the dominant perennial canopy-forming vegetation along the soft-sediment shores of the Northwest Atlantic. Eelgrass is considered an ecologically significant species in Atlantic Canada as it provides essential ecosystem functions and services and is an indicator of ecosystem health. Recent declines of eelgrass habitats...
Article
Full-text available
While the physical dimensions of climate change are now routinely assessed through multimodel intercomparisons, projected impacts on the global ocean ecosystem generally rely on individual models with a specific set of assumptions. To address these single-model limitations, we present standardized ensemble projections from six global marine ecosyst...
Article
Full-text available
Coastal biogenic habitats are vulnerable to human impacts from both terrestrial and marine realms. Yet the broad spatial scale used in current approaches of quantifying anthropogenic stressors is not relevant to the finer scales affecting most coastal habitats. We developed a standardized human impact metric that includes five bay-scale and four lo...
Article
Full-text available
Aim Climate change is predicted to alter the distribution and abundance of marine species, including canopy‐forming seaweeds which provide important ecosystem functions and services. We asked whether continued warming will affect the distribution of six common canopy‐forming species: mid‐intertidal fucoids (Ascophyllum nodosum, Fucus vesiculosus),...
Article
Full-text available
Global impact models represent process-level understanding of how natural and human systems may be affected by climate change. Their projections are used in integrated assessments of climate change. Here we test, for the first time, systematically across many important systems, how well such impact models capture the impacts of extreme climate cond...
Article
Full-text available
The Atlantic halibut (Hippoglossus hippoglossus) longline fishery is the second most valuable groundfish fishery in Atlantic Canada and received Marine Stewardship Council certification in 2013. The bottom longline fishery accounts for most halibut landings but incidentally catches nontargeted species (bycatch). Since 1998, Fisheries and Oceans Can...
Article
Full-text available
The Atlantic halibut (Hippoglossus hippoglossus) longline fishery is the second most valuable groundfish fishery in Atlantic Canada and received Marine Stewardship Council certification in 2013. The bottom longline fishery accounts for most halibut landings but incidentally catches nontargeted species (bycatch). Since 1998, Fisheries and Oceans Can...
Chapter
Full-text available
This Special Report on the Ocean and Cryosphere1 in a Changing Climate (SROCC) was prepared following an IPCC Panel decision in 2016 to prepare three Special Reports during the Sixth Assessment Cycle2 . By assessing new scientific literature3 , the SROCC4 responds to government and observer organization proposals. The SROCC follows the other two Sp...
Preprint
Full-text available
Climate change is shifting the abundance and distribution of marine species with consequences for ecosystem functioning, seafood supply, management and conservation. Several approaches for future projection exist but these have never been compared systematically to assess their variability. We conducted standardized ensemble projections including 6...
Article
Climate change effects on marine ecosystems include impacts on primary production, ocean temperature, species distributions, and abundance at local to global scales. These changes will significantly alter marine ecosystem structure and function with associated socio-economic impacts on ecosystem services, marine fisheries, and fishery-dependent soc...
Article
Nitrogen loading has been linked to eutrophication and seagrass bed declines worldwide, yet early warning signs and potential mitigating factors are often less clear. Our objective was to use published nitrogen loading model results together with eelgrass habitat surveys from 7 bays in Atlantic Canada to assess linkages between nitrogen loading, ti...
Preprint
Full-text available
Coastal biogenic habitats are particularly vulnerable to cumulative human impacts from both terrestrial and marine realms. Yet the broad spatial scale used in current global or regional approaches of quantifying multiple anthropogenic stressors are not relevant to the local or bay-wide scales affecting most coastal biogenic habitats. To fill this g...
Article
Full-text available
Eelgrass ( Zostera marina ) has been designated an Ecologically Significant Species in Atlantic Canada. The development and rapid expansion of netpen finfish aquaculture into sensitive coastal habitats has raised concerns about the impacts of finfish aquaculture on eelgrass habitats. To date, no studies have been done in Atlantic Canada to examine...
Data
Raw infauna, eelgrass, and environmental data from Port Mouton Bay
Article
Sea-cage finfish aquaculture frequently spatially overlaps and competes with traditional fisheries and ecologically important habitats in the coastal zone. Yet only few empirical studies exist on the effects of sea-cage aquaculture on commercially important fish and shellfish species, due to the lack of data. We present results from a unique collab...
Technical Report
Full-text available
Nutrient loading from anthropogenic sources has implications for the health and functioning of aquatic species and ecosystems. Using a nutrient loading model (NLM), nitrogen loading from point and non-point sources was estimated for 21 Nova Scotia bays where eelgrass (Zostera marina) has been documented. Overall, atmospheric deposition contributed...
Article
Full-text available
Model intercomparison studies in the climate and Earth sciences communities have been crucial to building credibility and coherence for future projections. They have quantified variability among models, spurred model development, contrasted within- and among-model uncertainty, assessed model fits to historical data, and provided ensemble projection...
Preprint
Full-text available
Eelgrass ( Zostera marina ) beds provide important habitat and food sources for a wide range of associated species both above- and belowground. Organic enrichment and nutrient loading from anthropogenic sources can change eelgrass canopy structure and macroinfauna community composition, making them important indicators of ecosystem health. In Atlan...
Preprint
Full-text available
Eelgrass ( Zostera marina ) beds provide important habitat and food sources for a wide range of associated species both above- and belowground. Organic enrichment and nutrient loading from anthropogenic sources can change eelgrass canopy structure and macroinfauna community composition, making them important indicators of ecosystem health. In Atlan...
Article
In the original article there was an error in Fig. 2a. Shoot density was measured in a 0.25 cm × 0.25 cm subset in the quadrat. To get m⁻², values were multiplied by 4. However, they should have been multiplied by 16. This does not change the results, only the magnitude of shoot density presented.
Article
The ocean is increasingly facing direct and indirect threats from multiple human activities that alter marine ecosystems worldwide. Mitigating these threats requires a global shift in the way people perceive and interact with the marine environment. Marine public perceptions research has emerged as a useful tool to understand public awareness and a...
Article
Seagrass beds and their associated species communities play key roles in coastal ecosystems. The importance of the ecological functions provided by eelgrass (Zostera marina) and macroinfauna are well understood; however, the spatial variation and linkage of the two are much less known. Here, we performed large-scale field surveys across three bioge...
Article
Full-text available
In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a special report in 2018 on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission...
Article
Synthetic organic polymers-or plastics-did not enter widespread use until the 1950s. By 2015, global production had increased to 322 million metric tons (Mt) year⁻¹, which approaches the total weight of the human population produced in plastic every year. Approximately half is used for packaging and other disposables, 40% of plastic waste is not ac...
Preprint
Full-text available
Model intercomparison studies in the climate and earth sciences communities have been crucial to build credibility and coherence for future projections. They have quantified variability among models, spurred model development, contrasted within- and among-model uncertainty, assessed model fits to historical data, and provided ensemble projections o...
Article
Full-text available
Fisheries and aquaculture make a crucial contribution to global food security, nutrition and livelihoods. However, the UN Sustainable Development Goals separate marine and terrestrial food production sectors and ecosystems. To sustainably meet increasing global demands for fish, the interlinkages among goals within and across fisheries, aquaculture...
Research
Full-text available
Lobster, shrimp, squid, crabs, and other invertebrates are increasingly important to the world’s supply of seafood, but managers often lack the information needed to ensure the catch is sustainable. Now, a series of studies has revealed for the first time that invertebrates are as important to marine ecosystems as forage fish, a group widely recogn...
Article
Eelgrass (Zostera marina) forms extensive beds in temperate coastal and estuarine environments worldwide and provides important ecosystem services, including habitat for a wide range of species as well as nutrient cycling and carbon storage. However, little is known about how eelgrass ecosystem structure and services differ naturally among regions....
Article
Over the past decades, much research has focused on understanding the critical factors for marine extinctions with the aim of preventing further species losses in the oceans. Although conservation and management strategies are enabling several species and populations to recover, others remain at low abundance levels or experience further declines....
Article
Eutrophication has caused strong shifts from perennial seagrass to opportunistic macroalgae and phytoplankton in many coastal ecosystems worldwide, yet responses of the primary-producer assemblage can vary with regional environmental and nutrient-loading conditions. The wider consequences of this variable primary-producer response on the associated...
Article
Since the 1950s, invertebrate fisheries catches have rapidly expanded globally to more than 10 million tonnes annually, with twice as many target species, and are now significant contributors to global seafood provision, export, trade and local livelihoods. Invertebrates play important and diverse functional roles in marine ecosystems, yet the ecos...
Article
Full-text available
In New Zealand and Nova Scotia, lobster (Jasus edwardsii and Homarus americanus, respectively) is the most valuable export fishery. Although stock assessments and indicators assist in evaluating lobster fisheries, ecosystem effects are largely unknown, hindering ecosystem-based fisheries management (EBFM). We employed ecosystem models for the Cook...
Chapter
Ambient temperature is very likely the most important environmental factor determining the distribution and diversity of life in the oceans. Hence, climate change is expected to alter marine biodiversity on a global scale. Here we review observed and predicted effects of climate change on the diversity of marine species. Overall, an increasing numb...
Article
Full-text available
Ascophyllum nodosum (rockweed) is a domi- nant, habitat-forming seaweed on intertidal rocky shores in the North Atlantic and commercially harvested in Can- ada, Maine and Europe. Rockweed plant structure varies regionally, and several morphotypes have been identified in Atlantic Canada alone. Yet the regionality of canopy struc- ture, associated sp...