scholarly journals Nematodes down under: State of knowledge and future trends

2018 ◽  
Vol 1 ◽  
Author(s):  
Gerhard du Preez ◽  
Nabil Majdi ◽  
Antoinette Swart ◽  
Walter Traunspurger ◽  
Hendrika Fourie
Keyword(s):  
Ecosystem Services ◽  
Food Source ◽  
Microbial Mats ◽  
Trophic Levels ◽  
Atmospheric Conditions ◽  
Community Assemblage ◽  
Nematode Assemblage ◽  
Nutrient Mineralization ◽  
Scientific Outputs ◽  
Ecological Importance

Nematodes inhabit most environments that address their need of water, carbon, and energy. They also play an important role in epigean food webs by occupying different trophic levels, while providing essential ecosystem services such as regulating decomposition and nutrient mineralization. Conversely, little is known about the role that nematodes play in subterranean ecosystems. For this reason, an in-depth review was undertaken in order to concatenate data from existing literature and provide a baseline for future studies. A total of 41 surveyed scientific works, published over a time period of 138 years, reported 295 unique taxa from 78 different cave systems. Although an increase in scientific outputs was recorded from the late 1990s, there is a considerable lack of information on cave-dwelling nematodes from Asia, South America, and North America. Also, only seven true cave-dwelling (troglobitic) species have been discovered, which may indicate a lack of comprehensive taxonomic efforts. From an ecological perspective, very few works have reported on the importance of nematode assemblages associated with cave ecosystems. This has resulted in the causal factors leading to population resilience processes, as well as trophic interactions, remaining mostly speculative. Nonetheless, the isolated cave-dwelling nematode assemblage associated with Movile Cave, including the true cave-dwelling species Chronogaster troglodytes, fulfills an important role by feeding on microbial mats and in turn serving as a food source for predators. This example of a cave nematode assemblage providing ecosystem services has inspired the undertaking of the Gcwihaba Caves Research Project, which aims at studying artificially opened caves in Ngamiland, Botswana. Compared to other caves in the area with natural openings, the artificially opened systems present different food source pathways, atmospheric conditions, and community assemblage structures. This provides a unique opportunity to study isolated cave communities, including nematode assemblages, as well as their ecological importance.

Multi-level social-ecological networks in a payments for ecosystem services programme in central Veracruz, Mexico

2020 ◽  
pp. 1-7
Author(s):  
Alfonso Langle-Flores ◽  
Adriana Aguilar Rodríguez ◽  
Humberto Romero-Uribe ◽  
Julia Ros-Cuéllar ◽  
Juan José Von Thaden
Keyword(s):  
Ecosystem Services ◽  
Spatial Scales ◽  
Payments For Ecosystem Services ◽  
Collaboration Network ◽  
Governmental Organizations ◽  
Social Ecological ◽  
Non Governmental Organizations ◽  
Conservation Activity ◽  
Ecological Importance ◽  
Hydrological Services

Summary Payments for ecosystem services (PES) programmes have been considered an important conservation mechanism to avoid deforestation. These environmental policies act in social and ecological contexts at different spatial scales. We evaluated the social-ecological fit between stakeholders and ecosystem processes in a local PES programme across three levels: social, ecological and social-ecological. We explored collaboration among stakeholders, assessed connectivity between forest units and evaluated conservation activity links between stakeholders and forest units. In addition, to increase programme effectiveness, we classified forest units based on their social and ecological importance. Our main findings suggest that non-governmental organizations occupy brokerage positions between landowners and government in a dense collaboration network. We also found a partial spatial misfit between conservation activity links and the forest units that provide the most hydrological services to Xalapa. We conclude that conservation efforts should be directed towards the middle and high part of the Pixquiac sub-watershed and that the role of non-governmental organizations as mediators should be strengthened to increase the efficiency and effectiveness of the local PES programme.

scholarly journals The Ecological Importance of Toxicity: Sea Anemones Maintain Toxic Defence When Bleached

Toxins ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 266 ◽  
Author(s):  
Cassie M. Hoepner ◽  
Catherine A. Abbott ◽  
Karen Burke da Silva
Keyword(s):  
Food Source ◽  
Environmental Stressors ◽  
Sea Anemones ◽  
Venomous Animals ◽  
Ecological Importance ◽  
Endosymbiotic Algae ◽  
Entacmaea Quadricolor ◽  
Impacts Of Climate Change

Cnidarians are amongst the most venomous animals on the planet. They are also under significant threat due to the impacts of climate change. Corals and anemones undergo climate-induced bleaching during extreme environmental conditions, where a loss of symbiotic photosynthetic algae (zooxanthellae) causes whitening in colour, loss of internal food supply, and reduction in health, which can ultimately lead to death. What has yet to be determined is whether bleaching causes a reduction in the production or quality of venom. In this study, the sea anemone Entacmaea quadricolor was exposed to long-term light-induced bleaching to examine the effect that bleaching has on venom. Venom quality and quantity, as determined through lethality and haemolysis measures and nematocyst production was highly preserved over the five-month imposed bleaching event. Maintenance of venom and nematocyst production, despite a loss of an internal food source provided by endosymbiotic algae, indicates both the ecological importance of maintaining toxicity and a remarkable resilience that anemones have to major environmental stressors.

scholarly journals Use of 3-Dimensional Videography as a Non-Lethal Way to Improve Visual Insect Sampling

Land ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 340
Author(s):  
Michael F. Curran ◽  
Kyle Summerfield ◽  
Emma-Jane Alexander ◽  
Shawn G. Lanning ◽  
Anna R. Schwyter ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Ecosystem Services ◽  
Ecosystem Restoration ◽  
Trophic Levels ◽  
Floral Resources ◽  
Sampling Techniques ◽  
Type I ◽  
3 Dimensional ◽  
Essential Components ◽  
Insect Sampling

Insects, the most diverse and abundant animal species on the planet, are critical in providing numerous ecosystem services which are significant to the United Nation’s Sustainable Development Goals (UN-SDGs). In addition to the UN-SDGs, the UN has declared the period 2021–2030 as the “Decade on Ecosystem Restoration.” Insects, because of the ecosystem services they provide, are critical indicators of restoration success. While the importance of insects in providing ecosystem services and their role in helping fulfil the UN-SDGs is recognized, traditional techniques to monitor insects may result in observer bias, high rates of type-I and type-II statistical error, and, perhaps most alarmingly, are often lethal. Since insects are critical in maintaining global food security, contribute to biological control and are a key food source for higher trophic levels, lethal sampling techniques which may harm insect populations are undesirable. In this study, we propose a method to visually sample insects which involves non-lethal 3-dimensional video cameras and virtual reality headsets. A total of eight observers viewed video captured insects visiting floral resources in a landscaped area on a university campus. While interobserver variability existed among individuals who partook in this study, the findings are similar to previous visual sampling studies. We demonstrate a combination of 3D video and virtual reality technology with a traditional insect count methodology, report monitoring results, and discuss benefits and future directions to improve insect sampling using these technologies. While improving quantitative monitoring techniques to study insects and other forms of life should always be strived for, it is a fitting time to introduce non-lethal sampling techniques as preservation and restoration of biodiversity are essential components of the UN-SDGs and the “Decade on Ecosystem Restoration”.

Biodiversity

2019 ◽  
pp. 27-44
Author(s):  
Nicola P. Randall ◽  
Barbara Smith
Keyword(s):  
Ecosystem Services ◽  
Environmental Change ◽  
Farming Systems ◽  
Growth Patterns ◽  
Natural Growth ◽  
Agricultural Change ◽  
Artificial Environment ◽  
Ecological Importance ◽  
The Impact ◽  
Soil And Water

This chapter discusses biodiversity in farming systems, including a consideration of the ecological importance of non-agricultural habitats within farm systems. The chapter outlines patterns of biodiversity in space and time, as well as at varying levels (genetic, organismal, landscape), before exploring the impact of agriculture on biodiversity at local, regional, and global scales. Farmland is an artificial environment, often characterized by monocultures grown at a density that differs from natural growth patterns. This can generate instability, resistance to environmental change, susceptibility to pests, pollution, and impacts on other ecosystem services such as soil and water. The chapter ends with a discussion of the biological implications of continued agricultural change (e.g. specialization, intensification).

Bioaccumulation trends of arsenic and antimony in a freshwater ecosystem affected by mine drainage

2016 ◽  
Vol 13 (1) ◽  
pp. 149 ◽  
Author(s):  
Meghan A. Dovick ◽  
Thomas R. Kulp ◽  
Robert S. Arkle ◽  
David S. Pilliod
Keyword(s):  
Food Web ◽  
Trophic Level ◽  
Microbial Mats ◽  
Mine Drainage ◽  
Trophic Levels ◽  
Whole Body ◽  
Freshwater Ecosystem ◽  
High Tolerance ◽  
Mine Site ◽  
The Past

Environmental context The food web behaviours of As and Sb are poorly understood. We compare As and Sb bioaccumulation in a contaminated freshwater ecosystem. Metalloid accumulation decreased with increasing trophic level. Bioprecipitated minerals in microbial mats represent a direct route of uptake (by ingestion) of metalloids to tadpoles, which contained the highest concentrations ever reported. We demonstrate food web bioaccumulation, but not biomagification, of As and Sb. We also report an unexpectedly high tolerance of tadpoles to metalloid toxicity. Abstract We compared As and Sb bioaccumulation and biomagnification when these metalloids co-occurred at varying environmental concentrations in a stream and wetlands near a contaminated mine site in Idaho (USA). We measured As and Sb concentrations in water and substrate samples, and in tissues of organisms representing several trophic levels. Bioaccumulation of both As and Sb was observed in stream organisms with the following trend of bio-diminution with increasing trophic level: primary producers>tadpoles>macroinvertebrates>trout. We also note reductions in metalloid concentrations in one of two stream remediation reaches engineered within the past 17 years to ameliorate metalloid contamination in the stream. Several wetlands contained thick microbial mats and were highly populated with boreal toad tadpoles that fed on them. The mats were extremely contaminated (up to 76564mgkg–1 As and 675mgkg–1 Sb) with amorphous As- and Sb-bearing minerals that we interpret as biogenic precipitates from geomicrobiological As- and Sb-cycling. Ingested mat material provided a direct source of metalloids to tadpoles, and concentrations of 3867mgkg–1 (As) and 375mgkg–1 (Sb) reported here represent the highest whole body As and Sb levels ever reported in living tadpoles. The bulk of tadpole metalloid burden remained in the gut despite attempts to purge the tadpoles prior to analysis. This study adds to a number of recent investigations reporting bioaccumulation, but not biomagnification, of As and Sb in food webs. Moreover, our results suggest that tadpoles, in particular, may be more resistant to metalloid contamination than previously assumed.

scholarly journals How farmers think about insects: perceptions of biodiversity, biodiversity loss and attitudes towards insect-friendly farming practices

2021 ◽  
Author(s):  
Maria Busse ◽  
Felix Zoll ◽  
Rosemarie Siebert ◽  
Annette Bartels ◽  
Anke Bokelmann ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Biodiversity Loss ◽  
Global Market ◽  
Agricultural Landscapes ◽  
Farming Practices ◽  
Agricultural Policies ◽  
Structured Interviews ◽  
Market Prices ◽  
Insect Biodiversity ◽  
Ecological Importance

AbstractAn alarming decrease of insects in number and variety calls for measures of protection and promotion, since insects are crucial for the functioning of ecosystems and provide multiple ecosystem services. Agricultural landscapes can provide vast insect habitats if they are managed accordingly. However, little is known about farmers’ problem awareness and attitudes toward insect biodiversity loss, related farming practises, or alternative acceptable insect-friendly solutions. To fill these research gaps, this paper aimed to reveal farmers’ perceptions and attitudes regarding these aspects in two German case studies. We conducted 23 semi-structured interviews with farmers in 2019 and qualitatively analysed them using semantic web analysis. Farmers mostly reported awareness of insects’ ecosystem services and disservices related to agricultural production rather than mentioning the holistic ecological importance of insects. About half of the farmers confirmed insect loss based on their own observations, whereas a similar number doubted there had been a decrease of insects. Most farmers are open-minded towards insect-friendly measures if financially compensated. The farmers also mentioned a joint societal responsibility for insects, economic pressure on farmers to use pesticides due to global market prices, and unbalanced agricultural policies. This study revealed in-depth insights into farmers’ thinking about insects and how farmers contextualise arguments. Our results identified overlaps in farmers’ mental models, which paves the way for co-designing insect-friendly farming practices in landscape labs. Local transformation efforts can also demonstrate new pathways for a shift on the higher levels.

scholarly journals Behavioral Interactions between Bacterivorous Nematodes and Predatory Bacteria in a Synthetic Community

2021 ◽  
Vol 9 (7) ◽  
pp. 1362
Author(s):  
Nicola Mayrhofer ◽  
Gregory J. Velicer ◽  
Kaitlin A. Schaal ◽  
Marie Vasse
Keyword(s):  
Empirical Studies ◽  
Predatory Behavior ◽  
Trophic Levels ◽  
Apex Predators ◽  
Behavioral Interactions ◽  
E Coli ◽  
C Elegans ◽  
Predatory Bacteria ◽  
Ecological Importance ◽  
Microbial Food Chain

Theory and empirical studies in metazoans predict that apex predators should shape the behavior and ecology of mesopredators and prey at lower trophic levels. Despite the ecological importance of microbial communities, few studies of predatory microbes examine such behavioral res-ponses and the multiplicity of trophic interactions. Here, we sought to assemble a three-level microbial food chain and to test for behavioral interactions between the predatory nematode Caenorhabditis elegans and the predatory social bacterium Myxococcus xanthus when cultured together with two basal prey bacteria that both predators can eat—Escherichia coli and Flavobacterium johnsoniae. We found that >90% of C. elegans worms failed to interact with M. xanthus even when it was the only potential prey species available, whereas most worms were attracted to pure patches of E. coli and F. johnsoniae. In addition, M. xanthus altered nematode predatory behavior on basal prey, repelling C. elegans from two-species patches that would be attractive without M. xanthus, an effect similar to that of C. elegans pathogens. The nematode also influenced the behavior of the bacterial predator: M. xanthus increased its predatory swarming rate in response to C. elegans in a manner dependent both on basal-prey identity and on worm density. Our results suggest that M. xanthus is an unattractive prey for some soil nematodes and is actively avoided when other prey are available. Most broadly, we found that nematode and bacterial predators mutually influence one another’s predatory behavior, with likely consequences for coevolution within complex microbial food webs.

scholarly journals Literature Synthesis for Assessment and Management of Seagrasses

2019 ◽  
pp. 67-76
Author(s):  
Cherry C. Favor
Keyword(s):  
Ecosystem Services ◽  
Management Practices ◽  
Anthropogenic Activities ◽  
Marine Ecosystem ◽  
Economic Valuation ◽  
The Philippines ◽  
Small Scale ◽  
Marine Habitat ◽  
Seagrass Meadows ◽  
Ecological Importance

This paper collates seagrass studies from 2008- 2017. The focus of review is on the studies conducted in Philippines and in some areas of world in relation to this dynamic and most productive marine ecosystem the seagrass meadows. The review reveals that there is an abundance in diversity, distribution and cover of seagrass in different parts of the country, wherein articles written in other part of the world provides data and information on physical, biological and economic importance of Seagrass in the human lives. The cause of its destruction was found out to be mostly anthropogenic activities. Limitations on the conducted studies in the Philippines was shown as reflected in the collected studies that are generally done along the coastal areas in the Visayas and Mindanao regions. Which practically shows an opportunity to explore different places in Luzon for an assessment of Seagrass for its ecosystem resiliency, stability, management and sustainability. Foreign studies included in the review reflects studies on assessment of biophysical characteristics of the seagrasses with the use of modern technologies like remote sensing and management practices that illustrates market value of ecosystem services of seagrass meadows on its application for some small-scale fisheries. Knowledge gap on socio-ecological importance of seagrasses, economic valuation of this marine habitat ecosystem services and wake up call for policy maker to consider seagrasses in their proposal for management shift of this ecologically significant habitat are topics needing further investigations.

scholarly journals Impact of the rust Puccinia linkii on Highbush Cranberry, Viburnum edule, near Smithers, British Columbia

2013 ◽  
Vol 127 (3) ◽  
pp. 270 ◽  
Author(s):  
Kiri Daust
Keyword(s):  
British Columbia ◽  
Rural Areas ◽  
Food Source ◽  
Leaf Tissue ◽  
Dead Leaf ◽  
Important Food ◽  
Important Food Source ◽  
Ecological Importance ◽  
The Impact

The berries of Highbush Cranberry (Viburnum edule) are an important food source for wildlife and for people in rural areas. In 2012 and 2013, many Highbush Cranberry plants in northwestern British Columbia were unusually severely infected by the rust Puccinia linkii, with telia covering up to half of each leaf. Given the ecological importance of the overwintering berries, I studied the impact of the infection on the production and quality of berries in mixed forests near Smithers, British Columbia. Sites where Highbush Cranberry bushes were infected with the rust had significantly more undeveloped berries. Plants from sites with higher levels of infection produced berries with significantly less sugar. Dead leaf tissue was also significantly more prevalent in infected plants. This study provides evidence that Puccinia linkii may stress plants, leading to reduced quality and quantity of berries, especially if the severity of the infection increases with the increasingly moist springs that are projected for the region.

scholarly journals Kindergarten Children’s Perception about the Ecological Roles of Living Organisms

2020 ◽  
Vol 12 (22) ◽  
pp. 9565
Author(s):  
Claudia Melis ◽  
Per-Arvid Wold ◽  
Anna Maria Billing ◽  
Kathrine Bjørgen ◽  
Børge Moe
Keyword(s):  
Ecosystem Services ◽  
Food Webs ◽  
Intrinsic Value ◽  
Trophic Levels ◽  
Kindergarten Children ◽  
Ecological Role ◽  
The Public ◽  
Raising Awareness ◽  
Living Organisms

Young children will inherit the biosphere; therefore, it is crucial that they recognize the importance of all living organisms based on their intrinsic value and ecosystem function, not only on their “cuteness”. However, children’s knowledge about the interdependence among organisms has been little investigated. We interviewed 56 kindergarten children (5–6 years old) in Norway. The aim of the study was to investigate their perception of the importance for nature of six organisms, representing different trophic levels of food webs (producers, consumers, decomposers) and providing different ecosystem services (production, decomposition, and pollination). There was no difference in ranking between sexes or between ordinary and farm-based kindergartens. Bumblebees and earthworms were perceived as the most important organisms, followed by squirrel, trees, and wolf. None of the children recognized the ecological role of mushrooms. Our results show that, although upon completing kindergarten many children had gained an early understanding of the role of different organisms in nature, they missed the importance of plants and fungi. Kindergarten children’s “fungi blindness” might reflect a neglect of the public for this extremely important, diverse, and dominating taxon. We should therefore put more emphasis in raising awareness about the interdependence among trophic levels in food webs.

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