scholarly journals Functional Feeding Groups of Macrofauna and Detritus Decomposition along a Gradient of Glacial Meltwater Influence in Tropical High-Andean Streams

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3303
Author(s):  
Patricio Andino ◽  
Rodrigo Espinosa ◽  
Verónica Crespo-Pérez ◽  
Sophie Cauvy-Frauníe ◽  
Olivier Dangles ◽  
...  
Keyword(s):  
Negative Relationship ◽  
Functional Feeding Groups ◽  
Minor Effect ◽  
Taxon Richness ◽  
Benthic Assemblages ◽  
Decomposition Rates ◽  
Feeding Mode ◽  
Chl A ◽  
Feeding Groups ◽  
The Difference

Tropical Andean glaciers are retreating rapidly, with possible consequences for trophic structure and ecosystem processes in high Andean meltwater streams. Here, we measured the environmental characteristics, quantified pools of particulate organic matter (POM) and periphyton (Chl. a), sampled benthic macroinvertebrates, determined functional feeding groups (FFG), and performed mesh bag decomposition experiments with Calamagrostis grass detritus at 17 stream sites along a gradient of glacial influence (GI) with 0–23% glacier cover in the catchment at 4050–4200 m a.s.l. in the Andes of Ecuador. POM was unrelated to GI while Chl. a. showed a weak (non-significant) negative relationship to GI. The macrofauna abundance decreased while taxon richness and the number of FFGs per site showed a hump-shaped relationship with increasing GI. Taxa with an opportunistic and generalist feeding mode generally dominated benthic assemblages and were related to high GI levels and low Chl. a. Only shredders were negatively related to GI, but unrelated to POM. Decomposition rates were comparable to those found in temperate alpine streams, and for both fine (0.0010–0.0065; median 0.0028 d−1) and coarse (0.0019–0.0088; median 0.0048 d−1) mesh bags, peaked at intermediate GI values, while the difference between bag types was small and almost constant along the GI gradient. This indicates an overall minor effect of macroinvertebrate shredders compared to that of microbes, in particular at high GI. It also suggests that the relatively high average temperature of these high-altitude equatorial streams (7–10 °C) does not produce higher decomposition rates than those in comparable but colder streams at temperate latitudes. The results suggest that, at the lower end of glacier cover, tropical glacier loss will not change the dominant microbial role in detritus decomposition, but that part of the physical abrasion could be partially replaced by biological shredding.

Preliminary Results on Aquatic Insects in the Me Linh Station for Biodiversity, Vinh Phuc Province

2017 ◽  
Vol 33 (4) ◽  
Author(s):  
Nguyen Van Hieu ◽  
Nguyen Van Vinh
Keyword(s):  
Quantitative Analysis ◽  
Aquatic Insects ◽  
Field Survey ◽  
Aquatic Insect ◽  
Insect Species ◽  
Functional Feeding Groups ◽  
Species Number ◽  
Feeding Groups ◽  
Preliminary Results

An intensive field survey on aquatic insects of Me Linh Station for Biodiversity in Vinhphuc province was conducted in December 2015. Specimens were collected at 8 different sites and aquatic insects were collected both quantitatively by Surber net and qualitatively by hand net, pond net. As a result, a total of 110 aquatic insect species belonging to 98 genera, 49 families and 9 orders were recognized. Among these, the order Ephemeroptera had the highest species number with 26 species, followed by Odonata with 25 species, Trichoptera with 18 species, Coleoptera with 15 species, Hemiptera with 11 species, Diptera with 9 species. Lepidoptera, Plecoptera and Megaloptera had the lowest of species number, represented by 3 species of Lepidoptera, 2 species of Plecoptera and 1 species of Megaloptera. Besides, the quantitative analysis results and the functional feeding groups were provided.

scholarly journals The Water Footprint of Primary and Secondary Processing of Beef from Different Cattle Breeds: A Value Fraction Allocation Model

2021 ◽  
Vol 13 (12) ◽  
pp. 6914
Author(s):  
Frikkie Alberts Maré ◽  
Henry Jordaan
Keyword(s):  
Water Footprint ◽  
Negative Relationship ◽  
High Water ◽  
Allocation Model ◽  
Cattle Breeds ◽  
A Value ◽  
Average Production ◽  
High Water Intake ◽  
The Difference ◽  
By Products

The high water intake and wastewater discharge of slaughterhouses have been a concern for many years. One neglected factor in previous research is allocating the water footprint (WF) to beef production’s different products and by-products. The objective of this article was to estimate the WF of different cattle breeds at a slaughterhouse and cutting plant and allocate it according to the different cuts (products) and by-products of beef based on the value fraction of each. The results indicated a negative relationship between the carcass weight and the processing WF when the different breeds were compared. Regarding a specific cut of beef, a kilogram of rib eye from the heaviest breed had a processing WF of 614.57 L/kg, compared to the 919.91 L/kg for the rib eye of the lightest breed. A comparison of the different cuts indicated that high-value cuts had higher WFs than low-value cuts. The difference between a kilogram of rib eye and flank was 426.26 L/kg for the heaviest breed and 637.86 L/kg for the lightest breed. An option to reduce the processing WF of beef is to lessen the WF by slaughtering heavier animals. This will require no extra investment from the slaughterhouse. At the same time, the returns should increase as the average production inputs per kilogram of output (carcass) should reduce, as the slaughterhouse will process more kilograms.

scholarly journals Microhabitat selection and distribution of functional feeding groups of mayfly larvae (Ephemeroptera) in lotic karst habitats

2018 ◽  
pp. 17 ◽  
Author(s):  
Marina Vilenica ◽  
Andreja Brigić ◽  
Michel Sartori ◽  
Zlatko Mihaljević
Keyword(s):  
Water Current ◽  
Functional Feeding Groups ◽  
Feeding Strategies ◽  
Microhabitat Selection ◽  
Dinaric Karst ◽  
Feeding Groups ◽  
Microhabitat Preferences ◽  
One Year ◽  
Physical And Chemical ◽  
Chemical Water

Research examining mayfly ecology in karst streams and rivers has increased in recent years, though microhabitat preferences remain poorly characterized. We examined mayfly assemblage taxonomy, functional feeding groups and microhabitat preferences in two contrasting lotic Dinaric karst catchments, one pristine and one anthropogenically impacted. At monthly intervals over a one-year period, all major microhabitats (i.e. dominated by boulders, cobbles, sand, silt, mosses, or angiosperms) were sampled at sites spanning springs, upper, middle and lower river reaches, and tufa barriers. In both catchments, mayfly species richness was comparable among microhabitats, while mayfly abundance was highest on mosses and lowest on silt. NMDS ordination did not group assemblages according to microhabitat type, which may reflect the greater influence of physical and chemical water properties. In both catchments and all microhabitats, mayfly assemblages were dominated by grazers/scrapers at upstream sites and by detritivores at downstream sites. Active filter feeders were more abundant in microhabitats with silt substrates and lower current velocities. This study demonstrated that certain mayfly species strongly preferred a specific microhabitat type, reflecting their water current preferences and feeding strategies, while other species shifted between microhabitats, likely in search of food resources and shelter. The results emphasize the importance of habitat heterogeneity in supporting diverse communities in karst rivers.

scholarly journals Interaction among Controlling Factors on Riverine DIN Export in Small Mountainous Rivers of Taiwan: Inseparable Human-Landscape System

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2981
Author(s):  
Wen-Shiuan Lee ◽  
Jr-Chuan Huang ◽  
Chung-Te Chang ◽  
Shih-Chien Chan ◽  
Ying-San Liou ◽  
...  
Keyword(s):  
Inorganic Nitrogen ◽  
Seasonal Pattern ◽  
Water Quality Management ◽  
Negative Relationship ◽  
Dry Season ◽  
Mitigation Strategies ◽  
Minor Effect ◽  
Dominant Form ◽  
Wide Range ◽  
Human Landscape

Increasing anthropogenic nitrogen (N) emission via different pathways has shown prominent impact on aquatic ecosystems for decades, but the effects of interaction among climate-, landscape- and human-associated variables on riverine DIN (dissolved inorganic nitrogen, mainly NO3− and NH4+) export are unclear. In this study, the data of 43 watersheds with a wide range of climate-, landscape- and human-associated gradients across Taiwan were evaluated with partial redundancy analysis (pRDA) to examine their interactive controls on riverine DIN export. Results show that the annual riverine DIN export in Taiwan is approximately 3100 kg-N km−2 yr−1, spanning from 230 kg-N km−2 yr−1 in less disturbed watersheds (eastern and central Taiwan) to 10,000 kg-N km−2 yr−1 in watersheds with intensive human intervention (southwestern and northern Taiwan). NO3− is generally the single dominant form of DIN, while NH4+ renders significance in disturbed watersheds. Nearly all environmental variables display a positive correlation with DIN export, except for landscape setting variables (e.g., slope, area, channel length), which show a negative relationship. In terms of seasonal pattern, climate and human-landscape variables are related to NO3− export independently in the wet season, yet in the dry season climate-human variables jointly dominate NO3− export. Meanwhile, human-landscape (LH) variables (λ1 of LH > 0.60) control NH4+ exports in both seasons, and human-associated (H) variables (λ1 of H = 0.13) have a minor effect on NH4+ exports in dry season. Precisely, the contribution of controlling variables on DIN export vary with species and seasons, indicating water quality management could be time-dependent, which should be taken into consideration for designing mitigation strategies.

scholarly journals Temporal variability predicts the magnitude of between-group attentional blink differences in developmental dyslexia: a meta-analysis

2014 ◽  
Author(s):  
Nicholas A Badcock ◽  
Joanna C Kidd
Keyword(s):  
Attentional Blink ◽  
Developmental Dyslexia ◽  
Meta Analysis ◽  
Negative Relationship ◽  
Visual Presentation ◽  
Stimulus Onset ◽  
Future Research ◽  
Temporal Position ◽  
Group Effect ◽  
The Difference

Background. Here we report on a meta-analysis of the attentional blink (AB) research focussed on specific reading impairment, commonly referred to as developmental dyslexia. The AB effect relates to a limitation in the allocation of attention over time and examined in a dual-target rapid serial visual presentation paradigm. When the second target appears in close temporal proximity to the first target, the second target is reported less accurately. Method. A Web of Science search with terms 'dyslexia attentional blink' returned 13 AB experiments (11 papers) conducted with developmental dyslexia (9 were included in this meta-analysis). The main pattern of performance was lower overall accuracy in groups of individuals with dyslexia relative to typically reading peers. That is, a between-group main effect. This meta-analysis examined the size of the between-group effect in relation to physical presentation characteristics, which differed between and within experiments. Results. Four noteworthy variables were related to the between group effect-size; fixation duration (positive relationship, R2 = .89, p <.01, n = 6), maximum temporal position of T2 (negative relationship, R2 = .46, p <.05, n = 9), the difference between the minimum and maximum temporal position of T2 (negative relationship, R2 = .53, p <.05, n = 9), and the stimulus onset asynchrony (negative relationship, R2 = .46, p <.05, n = 9). Discussion. These are discussed with respect to the preparation of task-set, temporal orienting, and speed of processing, recommending these as considerations for future research.

scholarly journals The Sensitivity of Wellbeing to Inequalities in Local Wellbeing

2021 ◽  
Author(s):  
◽  
Pascarn Ronald Dickinson
Keyword(s):  
New Zealand ◽  
Standard Deviation ◽  
Local Government ◽  
Subjective Wellbeing ◽  
General Social Survey ◽  
Negative Relationship ◽  
Cross Sectional ◽  
Underlying Causes ◽  
Important Addition ◽  
The Difference

<p>Research points to a robust negative relationship between average levels of subjective wellbeing and the distribution of subjective wellbeing. The fact that our wellbeing falls as wellbeing distributions widen suggests we care about inequalities in the lives of others. Central to this relationship is the role of place and human geography. The literature relating wellbeing to inequality in wellbeing is confined almost exclusively to inter-country comparisons. Virtually no attention has been paid to the relationship between wellbeing and inequality within countries - at the level of regions and below. The aim of this thesis is to test the generality of the inter-country evidence in the sub-national context.  I present four hypotheses which I test on three separate cross-sectional surveys: the New Zealand Quality of Life Survey, The New Zealand General Social Survey and the survey of Māori wellbeing, Te Kupenga. I follow the literature in using the standard deviation of wellbeing as a measure of wellbeing inequality. In each case the negative relationship between individual wellbeing and wellbeing inequality is clearly identifiable. The wellbeing effect of living in a place one standard deviation higher than another is roughly equivalent to the difference between the wellbeing of someone who is fully employed and someone who is unemployed and looking for work. Clearly we are highly sensitive to disparities in the subjective wellbeing of those around us.  I conduct several tests of the psychological drivers that lie behind the wellbeing response to local inequality in wellbeing. The first tests fairness perceptions, and finds sensitivity to wellbeing inequality to be higher among those who do not believe society is intrinsically fair. My test of altruism, while not as convincing empirically, suggests altruistic people may also be less affected by local wellbeing inequality. Both conclusions are consistent with the implied causation running from inequality to wellbeing.  While an important addition to the wellbeing literature, the more important implication of my findings is political. As the New Zealand Local Government Act comes up for renewal, the evidence I have assembled strongly supports providing local government with a clear purpose and the necessary funding to address the underlying causes of local inequalities in wellbeing. On empirical grounds alone, reducing wellbeing inequality is likely to make us all much happier.</p>

Discovery of coprolites in an Early Permian fern mesophyll

2022 ◽  
Vol 5 (1) ◽  
Author(s):  
WEI-MING ZHOU ◽  
MING-LI WAN ◽  
JOSEF PŠENIČKA ◽  
JUN WANG
Keyword(s):  
Terrestrial Ecosystem ◽  
Terrestrial Ecosystems ◽  
Functional Feeding Groups ◽  
Early Permian ◽  
Plant Organs ◽  
Feeding Groups ◽  
Fossil Records

Plants and arthropods interact with each other and constitute an important part of the modern terrestrial ecosystem (Schoonhoven et al., 2005). Historically, fossil records of plant-arthropod interactions have been well documented in Paleozoic terrestrial ecosystems, which were evidenced by large coprolites containing various plant fragments (e.g., Salter et al., 2012), small larvae and coprolites remained in plant organs (e.g., Feng et al., 2017), and diverse functional feeding groups discovered on plant stems, rachises, roots, leaves and fertile organs (e.g., Liu et al., 2020).

Functional feeding groups of Protist Ciliates (Protist: Ciliophora) on a neotropical flood plain

2021 ◽  
Vol 57 ◽  
pp. 13
Author(s):  
Bianca Ramos Meira ◽  
Melissa Progênio ◽  
Edilaine Corrêa Leite ◽  
Fernando Miranda Lansac-Tôha ◽  
Carolina Leite Guimarães Durán ◽  
...  
Keyword(s):  
Flood Plain ◽  
Food Resources ◽  
Functional Feeding Groups ◽  
Hydrodynamic Conditions ◽  
Efficient Tool ◽  
Ecological Processes ◽  
Clear Separation ◽  
Feeding Groups ◽  
Temporal Segregation ◽  
Influence Of Food

Functional diversity approaches have been an efficient tool in gaining a better understanding of how environmental conditions selected species in a given environment and how they share resources, linking ecological processes to biodiversity patterns. Although most of the protist ciliates are not highly specialized, functional feeding groups with species which ingest similar food can be identified. Thus, this study aimed to compare the abundance of different Functional Feeding Groups (FFG) of ciliates in environments with different hydrodynamic conditions (lotic and lentic) in different hydrological periods (high and low water) in a neotropical flood plain. The samples for analysis of the community of ciliates were taken in March and September of 2010 and 2011, at the subsurface of 12 different hydrodynamic environments. The results of an RDA showed a spatial and temporal segregation of the sampling units, based on the abundance and occurrence of the FFG. In addition, a clear influence of food resources on the structuring of functional ciliate guilds was evidenced. Thus, there were both temporal (hydrological periods) and spatial (different hydrodynamic environments) differences in the distribution of the FFG, with a clear separation of the FFGs between the years studied. In summary, the results of the categorization of species of ciliates in FFG responded satisfactorily suggesting fluctuations in different food resources, which reinforces the idea that the grouping of species by functional characteristics can be a good indicator of the responses of organisms to environmental fluctuations.

scholarly journals Phosphorus dynamics in a subtropical coastal lake in Southern Brazil

2019 ◽  
Vol 79 (1) ◽  
Author(s):  
Aurea L. Lemes da Silva ◽  
Mariana C. Hennemann ◽  
Mauricio M. Petrucio
Keyword(s):  
Organic Matter Content ◽  
Benthic Fauna ◽  
Size Composition ◽  
Matter Content ◽  
Functional Feeding Groups ◽  
Coastal Lake ◽  
Chl A ◽  
Significant Relationships ◽  
P Concentration ◽  
Total P

Temporal and spatial variations of organic and inorganic forms of phosphorus in the sediments of a subtropical oligo-mesotrophic shallow lake were investigated in relation to water column parameters, sediment characteristics and benthic fauna. The main results found were: 1) Phosphorus (P)  concentration varied seasonally, with organic P and total P  increasing in the sediments in warmer periods; 2) Sediment spatial variation, in terms of grain size composition and organic matter content, influenced P concentrations; 3) quantities and qualities of P in the sediments were positively correlated with water parameters, especially DO and NO3, Chl-a,  water temperature, pH, and total P. Negative correlations were observed between %OP and DO in sites 1, 3 and 4, and with NO3 in sites 2, 3 and 4; 4) benthic functional feeding groups showed significant relationships with temporal variation in sediment P concentration, including gathering-collectors, shredders, filterers and filtering-collectors. The results suggest a high importance of temperature mediated control of sediment-P release, both directly, through its direct effects on primary production and decomposition rates, and indirectly through its effects on other water and sediment parameters, especially dissolved oxygen concentration.

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