Open Access Publications

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Open access publications related to sustainability research.

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Lateral Transport Controls the Tidally Averaged Gravitationally Driven Estuarine Circulation: Tidal Mixing Effects
(Journal of Physical Oceanography, 2024-08-01) Kukulka, Tobias; Chant, Robert J.
In classic models of the tidally averaged gravitationally driven estuarine circulation, denser salty oceanic water moves up the estuary near the bottom, while less dense riverine water flows toward the ocean near the surface. Traditionally, it is assumed that the associated pressure gradient forces and salt advection are balanced by vertical mixing. This study, however, demonstrates that lateral (across the estuary width) transport processes are essential for maintaining the estuarine circulation. This is because for realistic estuarine bathymetry, the depth-integrated salt transport up the estuary is enhanced in the deeper estuary channel. A closed salt budget then requires the lateral transport of this excess salt in the deeper channel toward the estuarine flanks. To understand how such lateral transport affects the estuarine salt and momentum balances, we devise an idealized model with explicit lateral transport focusing on tidally averaged lateral mixing effects. Solutions for the along-estuary velocity and salinity are nondimensionalized to depend only on one single nondimensional parameter, referred to as the Fischer number, which describes the relative importance of lateral to vertical tidal mixing. For relatively strong lateral tidal mixing (greater Fischer number), salinity and velocity variations are predominantly vertical. For relatively weak lateral tidal mixing (smaller Fischer number), salinity and velocity variations are predominantly lateral. Overall, lateral transport greatly affects the estuarine circulation and controls the estuarine salinity intrusion length, which is demonstrated to scale inversely with the Fischer number.
Water-Energy-Food (WEF) Nexus and the SDGs in Central and South Asia
(Springer, Cham, 2024-08-04) Akram, Humayoun Akram; Mohazzam, Sardar; Ali, Saleem H.
The international research community has been attracted to the concept of a “water-energy-food” nexus as an approach for more integrated planning for global environmental change. The Sustainable Development Goals may well be approached using such a nexus approach for data gathering and for holistic policy implementation. This chapter considers how Central and South Asia might adopt this approach, particularly in the context of rapid development which is taking place across the region. We focus on energy efficiency and public-private partnerships as two key areas where robust metrics for such a nexus being realized hold promise. We also consider some of the criticism of the nexus approach in terms of research depth and policy implementation and the use of tools such as the Water Energy Food Nexus Index in the context of this region. Overall, we find the concept is appropriate for use in this region, particularly as a means of cross-border and regional development planning.
The Future Vintages of a Cultural Commodity in China: Silver Heights Winery Leader, Emma Gao
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Sanghvi, Shuchi; Sava, Nicholas; Wild, Kelly; Bullough, Amanda; Idowu-Kunlere, Tosin
This case study examines the outlook of China’s wine market from 2021 to 2022 with focus on the operations of Silver Heights Winery and its leader, Emma Gao. Due to Western influence and an expanding middle class, China has seen a recent spike in alcohol consumption, particularly with the luxury commodity of wine. Currently, China is one of the world’s leading populations in total wine drank per year, and winemakers from across the world rely heavily on these Asian consumer markets to maintain steady profits. In addition, the Chinese government is eager to become one of the world’s largest producers of wine to take a proverbial sip of these potential profits. The kicker is that in recent years, Chinese consumers seemed less likely to purchase a domestic commodity than their international counterparts, despite China’s growing popularity among wine connoisseurs. This case poses the question of whether Chinese winemakers should attempt to bridge the culture gap between Chinese wine labels and foreign audiences or if it is better to diagnose the issues that would allow them to tap the keg of a huge potential domestic consumer base in China. Learning Outcomes By the end of this case study, students should be able to: • Appraise the need for continued focus on cabernet sauvignon or product diversification. • Identify the competitors of Silver Heights Winery and how the organization can leverage its competitive advantage. • Identify the roles of the leadership of Silver Heights in preparing for global climate change. • Assess Emma Gao’s global mindset competencies and offer suggestions for how she can improve. • Recommend to the leaders of Silver Heights Winery whether to focus their operations on domestic Chinese markets or international markets.
The Future of Fast Fashion: H&M CEO, Helena Helmersson
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Melia, Lauren; Soja, Marie; Velazquez-Segura, Noe; Bullough, Amanda; Idowu-Kunlere, Tosin
The fast fashion industry has long been known for its negative impacts on the environment, and exploitation of workers due to its mass production business model. One brand is leading the charge to rewrite the narrative surrounding fast fashion and make it a greener and safer industry. The current CEO of H&M, Helena Helmersson, is addressing these concerns as part of her long-term vision for the brand to improve. H&M's mission is to embrace sustainability, respect human rights, and make fashion accessible for all. This case study looks at the impact Helmersson and her leadership strategies have had on the sustainability and ethical initiatives at H&M. It will also highlight how she has become a changemaker in the fashion industry by leading with a global mindset and ensuring H&M's focus on sustainability, human rights, diversity in the company, and changes in new market conditions. Learning Outcomes By the end of this case study, the students should be able to: • Appraise Helena Helmersson’s environmental and human rights efforts in alignment with public policy initiatives and UN Goals for sustainability. • Evaluate Helena Helmersson’s Global mindset. • Appreciate how Helena Helmersson evolved the H&M brand to adapt to new market conditions and behaviors.
Menstrual Health and Women’s Leadership: Flex Co. Global Expansion by Entrepreneur, Lauren Schulte Wang
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Greer, Brett; Maciolek, Michala; Williams, Lea; Bullough, Amanda; Idowu-Kunlere, Tosin
Flex Co’s vision is to “reimagine and deliver life-changing period products everywhere” by “creating body-positive and life-changing experiences through the products that we make and the conversations we spark” (Wang, 2017). This case examines period poverty and social stigma as issues women and girls face during their menstrual cycle and how insufficient infrastructure impacts women’s menstrual health and hygiene. It also analyzes how Flex Co., the U.S.’s #1 sustainable period brand, can expand its success into the Global Market. It also considers the effectiveness of its marketing strategy in the U.S. market and considerations to adapt or adjust the strategy when marketing to other cultures. Learning Outcomes By the end of this case study, the students should be able to: • Understand how culture shapes the perception of women and girls on their menstrual period, especially in developing countries. • Identify the challenges women and girls face in maintaining healthy menstrual hygiene. • Reflect on how the company leaders can turn their pain points into a global solution that many can access, just as Lauren Schulte Wang did. • Explore the growth opportunities for global expansion available to Flex Co.
Striving to Fix Social Problems: The Better Woman Foundation, Uganda
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Dunham, Aynsley; Gill, Ava; Hayden, Cam; Baker, Christine; Peng, Shihong; Bullough, Amanda
This case study examines the Better Women Foundation (BWF), a Ugandan nonprofit organization with the goal of helping Ugandan women and girls who face challenges related to education, healthcare, income generation, and gender-based violence. Topics included in the study include difficulties in promoting the organization, obtaining funding, recruiting and retaining volunteers, and infrastructure issues—particularly a lack of access to clean drinking water and reliable internet access and poor website construction—that hinder the ability of the organization to obtain funding or promote itself. Learning Outcomes By the end of this case study, the students should: ● Recognize common issues of financial resource scarcity facing nonprofits. ● Learn about the challenges that women in rural areas like Uganda face daily related to accessing clean water. ● Understand the importance of human capital to the success of a nonprofit organization. ● Appreciate the challenges and value of internet marketing and website formation for nonprofits.
Struggling to Educate Children: Erevuka Dada, Kenya
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Dunham, Aynsley; Reilly, Lexi; Stoll, Kameron; Reeves, Stephen; Bullough, Amanda
Erevuka Dada is a Kenyan nonprofit organization focused on providing sexual and reproductive health education to children in the rural east coast of Kenya. Unfortunately, the organization is struggling to establish programs or grow due to a lack of funding resulting from a lack of internal structure. Topics for discussion include the importance of written business plans and budgets and the value of mission and vision statements. Learning Outcomes By the end of this case, students should: ● Understand the importance of written business documents in obtaining funding for nonprofit organizations. ● Appreciate the need for clear professional structures and internet visibility for a nonprofit’s credibility and ability to carry out its mission. ● Consider possible challenges with the location of the business vis-à-vis the leaders.
Lacking Motivation, Legitimacy, and Structure: The Case of Être Une Femme, a Cote d’Ivoire Non-profit
(Women’s Leadership Initiative, Lerner College of Business & Economics, University of Delaware, 2024) Dunham, Aynsley; Mastronardi, Jack; Ruoff, Grace; Jones, Lynn; Bullough, Amanda
This case study examines Être Une Femme, a nonprofit organization in Côte d’Ivoire, known in English as the Ivory Coast in West Africa, to defend the right to education for women and girls, to empower women and girls to be financially independent and to speak out against domestic violence and defend the victims. Topics discussed in this case include difficulties in motivating leadership in a non-profit, considering limited success from their efforts and an inability to receive monetary incentives and support. This case also explores interweaving needs and structures to ensure tasks can be completed to realize the organization’s mission and goals. Learning Outcomes By the end of this case, students should: ● Understand the importance of motivation among the leaders of an organization and how to motivate others ● Appreciate clear professional procedures and internal structures for a non-profit’s ability to carry out its mission.
Neighborhood disadvantage is associated with working memory and hippocampal volumes among older adults
(Aging, Neuropsychology and Cognition, 2024-04-24) Wright, Regina S.; Allan, Alexa C.; Gamaldo, Alyssa A.; Morgan, Adrienne A.; Lee, Anna K.; Erus, Guray; Davatzikos, Christos; Bygrave, Desirée C.
It is not well understood how neighborhood disadvantage is associated with specific domains of cognitive function and underlying brain health within older adults. Thus, the objective was to examine associations between neighborhood disadvantage, brain health, and cognitive performance, and examine whether associations were more pronounced among women. The study included 136 older adults who underwent cognitive testing and MRI. Neighborhood disadvantage was characterized using the Area Deprivation Index (ADI). Descriptive statistics, bivariate correlations, and multiple regressions were run. Multiple regressions, adjusted for age, sex, education, and depression, showed that higher ADI state rankings (greater disadvantage) were associated with poorer working memory performance (p < .01) and lower hippocampal volumes (p < .01), but not total, frontal, and white matter lesion volumes, nor visual and verbal memory performance. There were no significant sex interactions. Findings suggest that greater neighborhood disadvantage may play a role in working memory and underlying brain structure.
Disruption, adaptation, and maintenance of domestic violence services during the COVID-19 pandemic
(Critical Public Health, 2024-04-18) Horney, Jennifer A.; Pena, Annaliese; Scales, Sarah E.; Fleury-Steiner, Ruth E.; Camphausen, Lauren C.; Miller, Susan L.
COVID-19 disrupted many aspects of domestic violence services including sheltering, in-person advocacy, and access to mental health, visitation, and legal services. Increased demand for services occurred concurrent with the highest levels of pandemic disruptions. Adaptations to many systems and services were made to address survivor’s changing needs. To understand how various aspects of service provision were disrupted during the pandemic, we surveyed a national census of U.S. based domestic violence direct service agencies. Email addresses were collected from online directories and each agency received a link to complete a survey using the online platform Qualtrics. The survey included five sections: services provided; work environment during COVID-19; disruptions caused by COVID-19; personal and organizational disaster preparedness; and demographics. Twenty-two percent of 1,341 agencies responded to the survey. At the start of the pandemic, the most disrupted services were legal and court, sheltering, and mental health/counselling services. Hazard pay, flexible scheduling, and additional information technology support were most frequently mentioned supports provided to mitigate disruptions and support providers and advocates. Disruptions and supports changed over the course of the pandemic. The COVID-19 pandemic disrupted the provision of services and advocacy to victims and survivors of domestic violence. Adaptations were made as new control measures were available (e.g. vaccines) and lessons learned were identified (e.g. successful implementation of virtual legal and court services). Maintaining supportive measures post-pandemic will require continued investment in this chronically underfunded, yet critical, sector and applying lessons learned from COVID-19 related disruptions and adaptations.
A comparative assessment of household power failure coping strategies in three American cities
(Energy Research and Social Science, 2024-05-19) Andresen, Adam X.; Kurtz, Liza C.; Chakalian, Paul M.; Hondula, David M.; Meerow, Sara; Gall, Melanie
Household power outage experiences vary based on outage characteristics and the household's ability to cope with a disruption. While disaster management scholarship has produced methods to predict where the most significant impacts of a hazard may occur, these methods do not anticipate secondary effects, such as those from power outages. This research is necessary as the expected risks associated with power outages will increase in the United States due to climate change, increasing electricity demand, and aging infrastructure. To understand households' power outage experiences, we collected 896 surveys from three cities in the United States: Detroit, MI; Miami, FL; and Phoenix, AZ. Participants were recruited through Amazon's Mechanical Turk (MTurk) service to complete a survey. We hypothesized that racial/ethnic minority groups, specifically non-white households and lower-income households experienced more frequent and prolonged power outages. We also hypothesized that the same groups were more likely to have experienced more significant adverse effects, such as throwing away perishable food and not receiving assistance. We found that non-white households in Phoenix and Detroit were more likely to experience longer outages than white households; however, this association was not present in Miami and was not statistically significant in any city. Income was not a major factor in predicting food waste or assistance received during the longest self-reported outage. Further assessments in varying geographical contexts and more generalizable samples are necessary to increase understanding of how households experience power outages.
Spatiotemporal patterns in habitat use of natal and non-natal adult Atlantic sturgeon in two spawning rivers
(Animal Biotelemetry, 2024-04-24) White, Shannon; Breece, Matthew; Fox, Dewayne; Kazyak, David; Higgs, Amanda; Park, Ian; Busch, Cassia; Lubinski, Barbara; Johnson, Robin; Welsh, Amy
Background Monitoring movement across an organism’s ontogeny is often challenging, particularly for long-lived or wide-ranging species. When empirical data are unavailable, general knowledge about species’ ecology may be used to make assumptions about habitat use across space or time. However, inferences about habitat use based on population-level ecology may overlook important eco-evolutionary contributions from individuals with heterogenous ethologies and could diminish the efficacy of conservation and management. Methods We analyzed over a decade of acoustic telemetry data to understand individual differences in habitat use of federally endangered adult Atlantic sturgeon (Acipenser o. oxyrinchus) in the Delaware and Hudson rivers during spawning season. In particular, we sought to understand whether sex or natal origin could predict patterns in habitat use, as there is a long-held assumption that adult Atlantic sturgeon seldom stray into non-natal rivers. Results In both rivers, migration timing, spawning habitat occupancy, and maximum upstream migration distance were similar between natal and non-natal individuals. While non-natal individuals represented only 13% of fish detected in the Hudson River, nearly half of all tagged fish detected in the Delaware River were non-natal and generally occupied freshwater habitats longer than natal individuals. In both systems males had more heterogenous patterns of habitat use and longer duration of occupancy than did females. Conclusions This study demonstrates the importance of non-natal rivers for fulfilling ontogenetic habitat requirements in Atlantic sturgeon. Our results may also highlight an opportunity to improve conservation and management by extending habitat designations to account for more heterogenous patterns in individual habitat use in non-natal freshwater environments.
Living, learning, working, and playing during COVID-19: tackling existing and exacerbated problems of low-income Singaporean youth
(Asia Pacific Journal of Social Work and Development, 2024-02-12) Kwan, Jin Yao; Tan, Joshua; Yi Jie, Chua; Khor, Joanna
COVID-19’s adverse, disproportionate impact on low-income youth — prompting youth-serving professionals to adapt and adjust — is well-documented. However, research gaps exist, including explanatory processes underlying COVID-19’s deleterious impact, systematic documentation of existing and exacerbated problems, and short- and long-term responses of youth-serving professionals. Using a multi-informant mixed methods design guided by a live-learn-work-play theoretical framework, exploratory findings indicated that COVID-19 worsened existing problems across all domains. In the short-term, Singaporean professionals prioritised, moved online, and evaluated programmes. Progressively, they sought to build youth communities, empower families, collaborate, and experiment. Findings have implications for understanding and resolving structural problems perpetuating pre-disaster vulnerabilities.
Evolving wildlife management cultures of governance through Indigenous Knowledges and perspectives
(The Journal of Wildlife Management, 2024-04-17) Fisk, Jonathan James; Leong, Kirsten Mya; Berl, Richard E. W.; Long, Jonathan W.; Landon, Adam C.; Adams, Melinda M.; Hankins, Don L.; Williams, Christopher K.; Lake, Frank K.; Salerno, Jonathan
Within governance agencies, academia, and communities alike, there are increasing calls to recognize the value and importance of culture within social-ecological systems and to better implement Indigenous sciences in research, policy, and management. Efforts thus far have raised questions about the best ethical practices to do so. Engaging with plural worldviews and perspectives on their own terms reflects cultural evolutionary processes driving paradigm shifts in 3 fundamental areas of natural resource management: conceptualizations of natural resources and ecosystems, processes of public participation and governance, and relationships with Indigenous Peoples and communities with differing worldviews. We broadly describe evolution toward these paradigm shifts in fish and wildlife management. We then use 3 case studies to illustrate the ongoing cultural evolution of relationships between wildlife management and Indigenous practices within specific historical and social-ecological contexts and reflect on common barriers to appropriately engaging with Indigenous paradigms and lifeways. Our case studies highlight 3 priorities that can assist the field of wildlife management in achieving the changes necessary to bridge incommensurable worldviews: acknowledging and reconciling historical legacies and their continued power dynamics as part of social-ecological systems, establishing governance arrangements that move beyond attempts to extract cultural information from communities to integrate Indigenous Knowledges into dominant management paradigms, and engaging in critical reflexivity and reciprocal, accountable relationship building. Implementing these changes will take time and a commitment to processes that may initially feel uncomfortable and unfamiliar but have potential to be transformative. Ethical and culturally appropriate methods to include plural and multivocal perspectives and worldviews on their own terms are needed to transform wildlife management to achieve more effective and just management outcomes for all.
Assessing relationships of cover crop biomass and nitrogen content to multispectral imagery
(Agronomy Journal, 2024-02-29) Miller, Jarrod O.; Shober, Amy L.; Taraila, Jamie
Cover crops provide valuable roles in sustainable agriculture, provided they produce enough biomass. To accurately measure their services to field management, spatial estimates would be useful to producers. This study used multispectral drone imagery to produce maps of normalized difference vegetation index (NDVI), normalized difference red edge index (NDRE), and a digital surface model (DSM) of cover crop plots on sandy, Mid-Atlantic soils. Cover crops included cereal rye (Secale cereale), mixtures of rye and crimson clover (Trifolium incarnatum), and mixtures of rye and hairy vetch (Vicia villosa). Their biomass was sampled in the spring of 2019, 2020, and 2021, dried, weighed, and analyzed for total nitrogen (N) content. Measurements of NDVI became saturated (i.e., reached a linear plateau) at 3.86 Mg biomass ha−1, NDRE at 5.72 Mg biomass ha−1, and the DSM at 5.11 Mg biomass ha−1. The measured N content became saturated at 80.9, 139.1, and 75 kg N ha−1 for NDVI, NDRE, and the DSM, respectively. Based on log transformations, NDVI was a stronger predictor of biomass and N, but not C:N. The NDRE was important for biomass, N, and C:N, while the DSM interactions with cover crop species helped predict both the N content and C:N of cover crop tissues. Accumulated growing degree days was important as an individual variable for biomass and N and as an interaction with cover crop species. Abbreviations DSM digital surface model GDD growing degree days NDRE normalized difference red edge index NDVI normalized difference vegetation index
A recreation demand model for warmwater fishing in Delaware with welfare effects for improvements in catch rates, species diversity, and water clarity
(Agricultural and Resource Economics Review, 2024-03-18) Dalvand, Kaveh; Parsons, George
We estimate a recreation demand model for warmwater fishing in Delaware and then use it to measure welfare gains associated with improved fishing quality as measured by catch rate of fish, diversity of species, and clarity of water. We use a “linked” site choice – trip frequency model with data gathered by the Delaware Division of Fish and Wildlife. Our site choice model includes 118 rivers and lakes in the state with detailed characteristics of each. We develop hypothetical scenarios of fishing quality improvement involving combinations of fish catch, fish diversity, and water clarity and apply it to individual water bodies, water basins, selected water body groupings, and statewide. Values are reported in seasonal per angler and aggregate terms.
Common ragweed (Ambrosia artemisiifolia L.) accessions in the Mid-Atlantic region resistant to ALS-, PPO-, and EPSPS-inhibiting herbicides
(Weed Technology, 2024-03-08) D’Amico Jr. , Frank; Besanҫon, Thierry; Koehler, Alyssa; Shergill, Lovreet; Ziegler, Melissa; VanGessel, Mark
Common ragweed is a troublesome weed in many crops. Farmers and crop advisors in the coastal Mid-Atlantic region have reported inadequate control of common ragweed in soybean fields with glyphosate and other herbicide modes of action. To determine whether herbicide resistance was one of the causes of poor herbicide performance, 29 accessions from four states (Delaware, Maryland, New Jersey, and Virginia) where common ragweed plants survived herbicide applications and produced viable seeds were used for greenhouse screening. Common ragweed seedlings from those accessions were treated with multiple rates of cloransulam, fomesafen, or glyphosate, applied individually postemergence (POST). All accessions except one demonstrated resistance to at least one of the herbicides applied at twice the effective rate (2×), 17 accessions were two-way resistant (to glyphosate and cloransulam, or to glyphosate and fomesafen), and three-way resistance was present in eight accessions collected from three different states. Based on the POST study, five accessions were treated preemergence (PRE) with herbicides that inhibit acetolactate synthase (ALS), and two accessions were treated with herbicides that inhibit protoporphyrinogen oxidase (PPO). All accessions treated PRE with the ALS inhibitors chlorimuron or cloransulam demonstrated resistance at the 2× rates. Both accessions treated PRE with the PPO inhibitor sulfentrazone had survivors at the 2× rate. When the same accessions were treated PRE with fomesafen, one had survivors at the 2× rate, and one had survivors at the 1× rate. Results from these tests confirmed common ragweed with three-way resistance to POST herbicides is widespread in the region. In addition, this is the first confirmation that common ragweed accessions in the region are also resistant to ALS- or PPO-inhibiting herbicides when applied PRE.
Supporting physical activity adoption through recommender system technology: A pilot study
(Journal of Health Psychology, 2024-04-16) Agans, Jennifer P.; Ma, Fenglong; Schade, Serena; Sciamanna, Christopher
We tested the potential for recommender system technology to provide personalized physical activity (PA) suggestions for inactive young adults with high bodyweight. We developed a recommender system using data from the 2017 Behavioral Risk Factor Surveillance System and assessed interest in using the system among 47 young adults (mean age = 23.0 years; 63.4% female; 65.0% White; mean BMI = 29.4). Eleven of these participants (mean age = 23.6 years; 90.9% female, 63.6% White; average BMI = 28.5) also received a PA recommendation and a follow-up interview. Approximately half of the survey participants were willing to use the recommender system, and participants interested in the recommender system differed from those unwilling to try the system (e.g., more likely to be female, worse self-perceived health). Furthermore, eight of the 11 interviewees tried the PA recommended to them, but had mixed reviews of the system’s accuracy. Although our recommender system requires improvements, such systems have promise for supporting PA adoption.
Contrasting roles of rice root iron plaque in retention and plant uptake of silicon, phosphorus, arsenic, and selenium in diverse paddy soils
(Plant and Soil, 2024-02-20) Linam, Franklin A.; Limmer, Matt A.; Seyfferth, Angelia L.
Background and aims Iron (Fe) plaque on rice roots is a mixture of Fe oxide and oxyhydroxide minerals thought to protect rice from high levels of arsenic (As) in flooded paddy soils. Silicon (Si), phosphorus (P), and selenium (Se) also exist as oxyanions in rice paddies, but the impacts of Fe plaque on uptake of these nutrients are unknown. Methods We used natural variation in paddy soil chemistry to test how Si, P, As, and Se move from porewater to plaque to plant via multiple techniques. In a pot study, we monitored Fe plaque deposition and porewater chemistry in 5 different soils over time and measured plaque/plant chemistry and Fe plaque mineralogy at harvest. We normalized oxyanion concentrations by Fe to determine the preferential retention on plaque or plant uptake. Results Low phosphorus availability increased root Fe-oxidizing activity, while Fe, Si, P, As, and Se concentrations in plaque were strongly correlated with porewater. Plaque did not appreciably retain Si and Se, and the oxyanions did not compete for adsorption sites on the Fe plaque. Conclusion Root Fe plaque seems to protect rice from As uptake, does not interfere with Si and Se uptake, and roots adapt to maintain P nutrition even with retention of porewater P on plaque.
Environmental drivers of biogeography and community structure in a Mid-Atlantic estuary
(Oecologia, 2024-02-14) Oleynik, Haley A.; Bizzarro, Joseph J.; Hale, Edward A.; Carlisle, Aaron B.
Estuaries include some of the most productive yet anthropogenically impacted marine ecosystems on the planet, and provide critical habitat to many ecologically and economically important marine species. In order to elucidate ecological function in estuaries, we must understand what factors drive community dynamics. Delaware Bay is the third largest estuary in the United States and hosts over 200 species of migrant and resident fishes and invertebrates. The Delaware Division of Fish and Wildlife has conducted two long-term trawl surveys at monthly intervals in Delaware Bay since 1966. The two surveys collect data on environmental conditions, species composition, and number of fishes and macroinvertebrates across different size classes and life histories. Using a suite of multivariate approaches including hierarchical cluster analysis, canonical correlation analysis, and permutational multivariate analysis of variance, we characterized the fish and macroinvertebrate community in Delaware Bay and found that community composition and environmental conditions varied across spatial and seasonal scales. We identified four distinct biogeographic regions, based on environmental conditions and community composition, which were consistent across surveys. We found that the community was driven primarily by gradients in temperature and salinity and that abundant, frequently occurring species in the Bay have well-defined environmental associations. Our work represents the first attempt to use an existing historical survey to better understand how environmental parameters influence diversity and distribution of macrofauna within Delaware Bay, providing insight into how abiotic variables, influenced by climate, may impact the Delaware Bay ecosystem and similar estuarine ecosystems worldwide.

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