Dormant Community Research Articles

Taxonomic and functional coherence of active and dormant zooplankton communities between perennial and temporary aquatic environments

Abstract We characterized the functional and taxonomic composition of the active and dormant communities from perennial lagoons and temporary ponds in a coastal plain. We sought to determine the degree of coherence between the egg bank and the active community within the same type of environment (temporary or perennial) and between environments subject to different hydrological cycles. We sampled the zooplankton community and environmental variables in six temporary ponds and five perennial lagoons in the dry and the wet periods of the hydrological cycle. Temporary ponds and perennial lagoons differed in abiotic conditions, with higher values of dissolved carbon in temporary ponds and higher values of salinity in perennial lagoons. The taxonomic coherence between active and dormant communities in temporary environments was greater than in perennial environments. In functional terms, we observed a high coherence between active and dormant communities for both types of environments. Our results highlight the need to conserve both temporary and perennial environments to assure the maintenance of zooplankton diversity. Although these environments are subject to the same set of climatic variables and pool of species, their idiosyncrasies are important forces promoting and sustaining biological diversity.

Chaos and Conception in the openED Archive

This essay discusses implementation of a community-based participatory research project with the goal to reactivate a dormant community archive. The openED project is the focus of this case study as it provides insight into everyday documentation practices through an assessment and inventory of the archival holdings of the Urbana-Champaign Independent Media Center (UCIMC) in Illinois. Established in 2000, the UCIMC is a grassroots collective of citizen journalists, artists, and community organizers. As an early hub in the nascent and global Indymedia network, this collective represents an antiglobalist and anticorporate agenda through magnifying community voices of underrepresented and marginalized groups. The UCIMC archive reflects this agenda, as it is a community-created collection of physical and digital materials representing the everyday documentation of the organization. From protest signs to radio and news articles, the core collection of member-created and member-collected material exists to support the activist mission of Indymedia. From the outset, the openED project faced a number of daunting challenges, both in locating the archival material and as the UCIMC entered a period of severe financial crisis in early 2019. This article is a reflection on lessons learned and strategies applied to create accessible and collaborative everyday documentation at the UCIMC community archive.

Uloga fabrike “Bratstvo” u razvoju Novog Travnika

The establishment of the socialist regime had led to thorough political, economic, social, cultural and other changes in Bosnia and Herzegovina. The first decade after the Second World War was marked by the reconstruction of the war-torn country, and great support in that process was provided by the USSR - the main ally of the new Yugoslavia. Emphasis was placed on the intensive development of the industry, which was to be the carrier of the overall economic development of the entire country. In accordance with this strategy, large industrial plants were established in all parts of Yugoslavia, thanks to which there was an intensive process of urbanization of numerous previously dormant communities. However, when there was a conflict and then a break with the USSR, Yugoslavia was forced to partially modify its economic development plans (the so-called Five-Year Plans). These changes in Bosnia and Herzegovina were most felt by cities such as Zenica, which instead of the originally planned Doboj became a Yugoslav metallurgical center, and Novi Travnik, which arose as a result of relocating part of the arms industry from Kragujevac in Serbia to central Bosnia. The factory “Bratstvo" (meaning Brotherhood) was built on a deserted meadow near Travnik in the heart of central Bosnia, and for the needs of housing workers who built industrial plants, as well as for those who worked in those plants, the first residential buildings were built in the form of low-quality wooden barracks. These were the roots of the workers' settlement that gradually grew into a new town called Novi Travnik. The fateful link between the factory and the city, which was established at that time, was not interrupted during the entire socialist period, so the survival and development of Novi Travnik completely depended on the business opportunities in the "Bratstvo" factory. The expansion of the production and plant of the "Bratstvo" also included the construction of new housing, communal, social, health, sports, cultural, catering and other facilities in Novi Travnik. A successful business year in "Bratstvo" meant a secure inflow of money into the local community budget as well as a sufficient number of funds for the work of cultural, artistic, entertainment, sports and all other societies in the city. The same rule applied in the case of bad business of "Bratstvo", and the most obvious example of how important the factory was for Novi Travnik can be seen in the case of a failed business in Ghana. The local authorities in Novi Travnik were absolutely aware of the role of the "Brotherhood" in the development of Novi Travnik and tried in every way to facilitate the functioning of the company, so, except for a few mere misunderstandings, relations between city and factory management were mostly friendly. After all, when the survival of the "Bratstvo" was called into question due to the failed business in Ghana, local authorities were among the first to appeal for the company's salvation, clearly noting that with the disappearance of the factory, the fate of Novi Travnik would be sealed. The paper presents a brief overview of the history of the company "Bratstvo" from its founding in June 1949 until the end of the socialist period in 1990, and analyses the relations between the city and factory authorities in that period. The aim of the paper was to show the importance that the factory "Bratstvo" had for the overall development of Novi Travnik and to determine how much the local authorities were aware of the role of companies in the development of the city. The paper provides insight into the processes that took place in a particular local community, but which can also be found in other industrial cities of Bosnia and Herzegovina and Yugoslavia during the socialist period.

Community structure and concordance patterns among zooplankton life stages in subtropical temporary ponds

In this study, we assessed the community structure (species richness and composition) and examined concordance patterns between the active and dormant life stages of the zooplankton (Rotifera, Cladocera and Copepoda) in Southern Brazilian temporary ponds. We also examined pairwise concordance patterns in the species richness and composition between each taxonomic group. We recorded 77 species in the study area. Active communities had higher species richness and a higher number of exclusive species compared to the dormant community. Low concordance was observed in the species richness and composition of the active and dormant communities. Significant patterns were detected between similar life stages of zooplankton taxonomic groups. We found significant concordance between the species richness of dormant stages of Cladocera and Rotifera, and between the active stages of Cladocera and Copepoda. We also detected significant concordant patterns in the similarity for composition of the active stages of Cladocera and Copepoda, and of Rotifera and Copepoda. The lack of concordance between life stages indicates that the dormant communities are not adequate surrogates of the overall diversity of the zooplankton in Southern Brazilian temporary wetlands, at least under similar experimental incubation conditions. However, there is initial evidence that cladocerans and copepods can be employed as surrogates of other zooplankton groups, if the conclusions are strictly limited to active stages of the community.

Spatial heterogeneity and long-term dynamics of cladoceran ephippia in a monsoonal reservoir, driven by hydrology and eutrophication

Most freshwater Cladocera produce ephippia to survive harsh episodes in their life cycle. Ephippia represent the dormant community in sediments and allow tracing population dynamics and community succession with environmental change in water bodies in time. As reservoirs are created by damming rivers, the species composition and structure of a dormant cladoceran community are expected to depend on trophic state as well as on hydrological conditions. We collected ephippia from sediments in the transition and lacustrine zones of Liuxihe reservoir, a warm-water impoundment in southern China. High species richness with low abundance was found in the transitional zone, while high abundance was found at the lacustrine zone. Ephippia identified Daphnia galeata as the first Cladocera colonizer of the newly created water body, but littoral or small sized species—Scapholeberis sp. and Bosmina sp. fast increased and became dominated from damming till the end of 1970s. Medium-sized pelagic species—Moina micrura and D. galeata—increased from 1975 onwards, corresponding to an increase in diatom abundance with slight eutrophication and hydrological shift due to the construction of two small dams in the upstream zone of the feeding rivers. A two-way stepwise linear regression analysis showed that spatial variables explained 33% of ephippial total abundance while diatom abundance explained 5.2%. Hydrological conditions in the dry season (October to next March) were unrelated to total ephippial abundance but explained 37.5% in the wet season (April to September). We conclude the distinct longitudinal gradient and vertical variation of the dormant community provide useful information for understanding of long-term dynamics of site-specific hydrological processes, primary productivity and hydrologic events.

Nanocalorimetric Characterization of Microbial Activity in Deep Subsurface Oceanic Crustal Fluids.

Although fluids within the upper oceanic basaltic crust harbor a substantial fraction of the total prokaryotic cells on Earth, the energy needs of this microbial population are unknown. In this study, a nanocalorimeter (sensitivity down to 1.2 nW ml-1) was used to measure the enthalpy of microbially catalyzed reactions as a function of temperature in samples from two distinct crustal fluid aquifers. Microorganisms in unamended, warm (63°C) and geochemically altered anoxic fluids taken from 292 meters sub-basement (msb) near the Juan de Fuca Ridge produced 267.3 mJ of heat over the course of 97 h during a step-wise isothermal scan from 35.5 to 85.0°C. Most of this heat signal likely stems from the germination of thermophilic endospores (6.66 × 104 cells ml-1FLUID) and their subsequent metabolic activity at temperatures greater than 50°C. The average cellular energy consumption (5.68 pW cell-1) reveals the high metabolic potential of a dormant community transported by fluids circulating through the ocean crust. By contrast, samples taken from 293 msb from cooler (3.8°C), relatively unaltered oxic fluids, produced 12.8 mJ of heat over the course of 14 h as temperature ramped from 34.8 to 43.0°C. Corresponding cell-specific energy turnover rates (0.18 pW cell-1) were converted to oxygen uptake rates of 24.5 nmol O2 ml-1FLUID d-1, validating previous model predictions of microbial activity in this environment. Given that the investigated fluids are characteristic of expansive areas of the upper oceanic crust, the measured metabolic heat rates can be used to constrain boundaries of habitability and microbial activity in the oceanic crust.

Assembly of Active Bacterial and Fungal Communities Along a Natural Environmental Gradient.

Dormancy is thought to promote biodiversity within microbial communities, but how assembly of the active community responds to changes in environmental conditions is unclear. To measure the active and dormant communities of bacteria and fungi colonizing decomposing litter in maple forests, we targeted ribosomal genes and transcripts across a natural environmental gradient. Within bacterial and fungal communities, the active and dormant communities were phylogenetically distinct, but patterns of phylogenetic clustering varied. For bacteria, active communities were significantly more clustered than dormant communities, while the reverse was found for fungi. The proportion of operational taxonomic units (OTUs) classified as active and the degree of phylogenetic clustering of the active bacterial communities declined with increasing pH and decreasing C/N. No significant correlations were found for the fungal community. The opposing pattern of phylogenetic clustering in dormant and active communities and the differential response of active communities to environmental gradients suggest that dormancy differentially structures bacterial and fungal communities.

Community structure of resting egg banks and concordance patterns between dormant and active zooplankters in tropical lakes

Little effort has been devoted to charac- terizing the resting egg banks in tropical lakes. In this study, we evaluated the structure of egg banks across 26 Brazilian lakes located in four geographical regions. We also evaluated cross-taxon concordance in species richness and community similarity between dormant rotifers and dormant cladocerans, and searched for concordant patterns between dormant and active communities. We observed 88 taxa among all the hatchlings that belonged mainly to rotifers and cladocerans. Lakes located in the same geographical region displayed more similar dormant communities. Overall, no concordance was observed between dormant rotifers and dormant cladocerans. Concor- dance in community similarity was observed between dormant and active organisms but only for rotifers and the entire zooplankton community. Resting egg banks were not associated to a set of environmental variables. Our results demonstrate the occurrence of resting egg banks in several tropical lakes. Due to the weak concordant patterns, rotifers or cladocerans found in egg banks should be used cautiously as a surrogate of the other group in zooplankton surveys. Finally, the lack of strong concordance between the active and dormant stages of cladocerans suggests that some species may not receive appropriate cues to induce diapause.

Zooplankton resting egg banks in permanent and temporary tropical aquatic systems

AIM: We evaluated zooplankton resting egg banks and active communities in five coastal lagoons and in five temporary pools, aiming to compare the active and the dormant communities in such environments. As they differ in hydroperiod, we expected that pools present richer resting egg banks in comparison to those found in lagoons. METHODS: Zooplankton community was sampled twice in 2006 (lagoons) and in 2010 (pools) and resting egg banks were sampled once in December 2007 (lagoons) and in May 2010 (pools). Resting eggs were isolated from the sediment by applying the sugar flotation method. RESULTS: In opposition to our expectation, species richness in the resting egg banks of pools did not differ from those of lagoons. Additionally, no difference was found between the active and the dormant zooplankton communities in each water body for both temporary and permanent environments. However, similarity between active and dormant communities was greater in permanent environments than it was in temporary environments. CONCLUSIONS: It seems that the diapause strategy observed in certain tropical zooplankton populations cannot be predicted based on the awareness of the environment type (permanent or temporary), since hatching cues may be species-specific.

Patterns of extracellular enzyme activities and microbial metabolism in an Arctic fjord of Svalbard and in the northern Gulf of Mexico: contrasts in carbon processing by pelagic microbial communities

The microbial community composition of polar and temperate ocean waters differs substantially, but the potential functional consequences of these differences are largely unexplored. We measured bacterial production, glucose metabolism, and the abilities of microbial communities to hydrolyze a range of polysaccharides in an Arctic fjord of Svalbard (Smeerenburg Fjord), and thus to initiate remineralization of high-molecular weight organic matter. We compared these data with similar measurements previously carried out in the northern Gulf of Mexico in order to investigate whether differences in the spectrum of enzyme activities measurable in Arctic and temperate environments are reflected in “downstream” aspects of microbial metabolism (metabolism of monomers and biomass production). Only four of six polysaccharide substrates were hydrolyzed in Smeerenburg Fjord; all were hydrolyzed in the upper water column of the Gulf. These patterns are consistent on an interannual basis. Bacterial protein production was comparable at both locations, but the pathways of glucose utilization differed. Glucose incorporation rate constants were comparatively higher in Svalbard, but glucose respiration rate constants were higher in surface waters of the Gulf. As a result, at the time of sampling ca. 75% of the glucose was incorporated into biomass in Svalbard, but in the northern Gulf of Mexico most of the glucose was respired to CO2. A limited range of enzyme activities is therefore not a sign of a dormant community or one unable to further process substrates resulting from extracellular enzymatic hydrolysis. The ultimate fate of carbohydrates in marine waters, however, is strongly dependent upon the specific capabilities of heterotrophic microbial communities in these disparate environments.

Reactivation of dormant and nonculturable bacterial forms from paleosoils and subsoil permafrost

Methods of reactivating the dormant forms (DFs) and nonculturable cells (NCs) of the bacterial communities of buried paleosoils and subsoil permafrost stored for long periods of time (thousands to millions of years), including completely sterile samples (CFU = 0), were developed. They were based on washing the DFs and NCs to remove anabiosis autoinducers (spore germination autoinhibitors) and introducing low molecular weight extracellular growth regulators of microbial or plant origin, such as alkylhydroxybenzenes of the alkylresorcinol subtype, indoleacetic acid, and wheat germ agglutinin. It was revealed that the dormant communities of permafrost and buried soils differed in their sensitivity to reactivating factors, probably due to different natural storage conditions of the tested soil substrates and the heterogeneity of dormant populations. The latter was confirmed by FISH (fluorescent in situ hybridization): applying the reactivation methods to the cells of the dormant permafrost community resulted in an increase in the number of metabolically active cells from 5 to 77% of their total number. In contrast, the addition of microbial anabiosis autoinducers (C12-AHB) to background surface soil and permafrost samples caused the transition of bacterial cells to the dormant or the nonculturable state, depending on the C12-AHB concentration and the sensitivity of the cells from the control soil or permafrost’ to it. The data obtained contribute to our knowledge concerning the role of intercellular communication factors and the survival of microorganisms under extreme environmental conditions.

Long‐term effects of salinity and disturbance regime on active and dormant crustacean communities

In a large‐scale and long‐term outdoor mesocosm (400‐liter) experiment, we studied the interacting effects of salinity and disturbance (hydrological) regime on the active and dormant crustacean communities of Mediterranean temporary wetlands (Camargue, southern France). Sixty‐four mesocosms, inoculated with a regional species pool (mixed dormant egg banks), were exposed to a full factorial treatment combination of four salinity levels and four disturbance regimes during three consecutive years. Both in the active and dormant community component, considerable shifts in community composition occurred because of direct and probably also second‐order effects of the treatments. All large branchiopod species had low long‐term salinity tolerances and showed species‐specific preferences for disturbance regimes according to their life cycle strategy. The highest salinity (5) was not limiting for cladocerans and ostracods, which thrived in the absence of the competitively stronger, predatory, and bioturbating large branchiopods. Copepods were negatively associated with salinity and coped better with the imposed biotic pressure. Zooplankton diversity and density peaked in intermediate‐disturbance regimes, probably because only specialized species survived the high‐disturbance regimes, whereas at low‐disturbance frequencies high densities of predatory Triops controlled zooplankton communities. Although crustacean dormant egg banks can temporarily buffer against unfavorable conditions, persisting bad conditions may lead to their exhaustion within 4 to 10 yr. Predicted aridification (leading to more intense disturbance regimes) may result in the loss of late successional species (chydorids and ostracods), whereas salinization may wipe out sensitive freshwater species such as large branchiopods.

Management of highland wetlands in central Kenya: the importance of community education, awareness and eco-tourism in biodiversity conservation

The loss of natural habitats through destructive anthropogenic activities has been identified as one of the major drivers of environmental degradation. This is even more prevalent in developing countries where poverty and ignorance of the value of biodiversity is rampant. A pilot study was conducted in two highland wetlands in central Kenya to compile baseline data through the use of field survey, questionnaire and subsequent seminars. The study showed that wetlands offer ecological, social and economic benefits that are not fully appreciated and hence there is a lack of concerted efforts to advocate for their sustainable use. Initial findings showed that both wetlands were rich in biodiversity, especially birds. However, these ecosystems were experiencing environmental problems such as dumping of solid waste, over abstraction of water, encroachment for commercial and residential use, wetland agriculture, overgrazing, improper land use practices on the watershed and wildlife poaching. A follow-up series of public awareness and education campaigns to sensitize the local communities to the importance of the two ecosystems helped change attitudes and perceptions. As a result, the local community organized themselves, revived a dormant community group, and for the last two years have created an eco-tourism venture that has helped address many of the above threats. Future conservation and management efforts for wetlands and their associated watersheds can achieve more with well informed stakeholders. Public education and awareness of the benefits of biodiversity conservation, adoption of wetland user-friendly alternatives, and income generating enterprises offer a unique opportunity to sustainably manage and conserve wetlands amidst increasing populations, poverty and limited resources.

Enhancing community welfare through improved water quality: a case for applying staggered pollution charges in the river Musi sub-basin of Andhra Pradesh, India

In conditions of severe water-pollution and dormant community acceptance of accumulating environmental damage, the regulator's role goes beyond pollution prevention and more towards remediation and solutions based on the community's long-term expectations of economic benefits from clean water. This paper suggests a method to enable these benefits to become perceptible progressively, through participatory clean-up operations, supported by staggered pollution charges. It analyses the relevant literature on pollution prevention and applies a cost-based “willingness to pay” model, using primary basin-level data of total marginal costs. It develops a replicable demand-side approach imposing charge-standard targets over time in urban-industrial basins of developing countries.