Bioindicators

Comparison of ant community composition across different land-use types: assessing morphological traits with more common methods

by Michelle Yates

Australian Journal of Entomology

Quantitative measures (morphological traits), which are influenced by species ecology, habitat use and more Quantitative measures (morphological traits), which are influenced by species ecology, habitat use and
evolutionary history, may be as important as species identity when assessing differences in community
structures among land-use types. We used ant communities as the response taxa to assess how three
different measures of community diversity differ across three different land-use types (Native Remnant,
Native Pasture and Crop Stubble). Ants were collected using pitfall traps and sorted into morphospecies,
abundances recorded, and classified into Andersen’s functional groups. Two morphological traits
(thorax length and mid-femur length) related to body size and dispersal ability were also measured to
assess if morphologically different suites of ants (e.g. short thorax and short mid-femur) were selected
for in each land-use type. Native Remnants exhibited the most speciose ant assemblages, as anticipated;
however, functional group structure did not differ significantly between land-use types. The relationship
between thorax and mid-femur length differed significantly between land-use types, with assemblages
within Crop Stubble exhibiting significantly higher femur: thorax ratio compared to Native
Remnants. We found that land management strategies not only impact on species richness but also on
the morphological traits exhibited by ants.

Multivariate approach in Lichen biomonitoring studies: Validation of Lichens as an efficient bioindicator

by Himanshu Rai

Conference Proceedings:
Himanshu Rai,Rajan K. Gupta, D.K. Upreti,  Multivariate approach in Lichen biomonitoring studies: Validation of Lichens as an efficient bioindicator,1st World Congress for Man and Nature, Global Climate Change & Biodiversity Conservation, 11-13 Nov. 201, Gurukul Kangri Vishwavidyalaya, Haridwar, Uttarakhand, India,pp.427.

Sedentary nestlings of Wood Stork as monitors of mercury contamination in the gold mining region of the Brazilian Pantanal

by Jo-Szu (Ross) Tsai

Del Lama, S. N., C. D. Rocha, W. F. Jardim, J.-S. Tsai, and P. C. Frederick. 2011. Environmental Research. In Press. DOI:10.1016/j.envres.2011.07.007

Sedentary organisms that are at top trophic levels allow inference about the level of local mercury contamination. We... more Sedentary organisms that are at top trophic levels allow inference about the level of local mercury contamination. We evaluated mercury contamination in feather tissue of nestling Wood Storks (Mycteria americana), sampled in different parts of the Brazilian Pantanal that were variably polluted by mercury releases from gold mining activities. Levels of mercury in feathers sampled in seven breeding colonies were determined by atomic absorption spectroscopy, and the mean value of mercury concentration was 0.557 μg/g, dry weight (n=124), range 0.024–4.423 μg/g. From this total sample, 21 feathers that represent 30% of nestlings collected in Porto da Fazenda and Tucum colonies, in the northern region, ranged from 1.0 to 4.43 μg/g, dry weight (median value=1.87 μg/g). We found significant differences among regions (H=57.342; p=0<0.05). Results suggest that permanently flooded areas, or along mainstream rivers are more contaminated by mercury than dry areas, regardless of the distance from the gold mining center, which is located in the northern Pantanal. Highest values found in nestlings feathers were similar to those found in feathers of adult birds and in tissues of adult mammals that are less sedentary and were captured in the same region of Pantanal. These findings indicate that mercury released has been biomagnified and it is present in high concentrations in tissues of top consumers. We suggest a program to monitor mercury availability in this ecosystem using sedentary life forms of top predators like Wood Storks or other piscivorous birds.

Diversity and distribution of terricolous lichens as indicator of habitat heterogeneity and grazing induced trampling in a temperate-alpine shrub and meadow

by Himanshu Rai

Himanshu Rai, D. K. Upreti and Rajan K. Gupta

Lichens are among the most sensitive biomonitors of ecosystem health and human induced disturbances. Terricolous... more Lichens are among the most sensitive biomonitors of ecosystem health and human induced disturbances. Terricolous lichens of Chopta–Tungnath (Garhwal, western Himalaya, India) were analysed for their ability to indicate habitat variability and disturbances induced by livestock grazing. Terricolous lichens were sampled from 12 sites, distributed across the three macrohabitats between 2,700 and 4,001 m, using 50 × 10 cm narrow frequency grids having five 10 × 10 cm sampling units. The terricolous lichen community of the area constituted, 20 species belonging to 10 genera, five families and four growth forms. Altitude and relative humidity were the major habitat factors found influencing the terricolous lichen community of the landscape. Fruticose and compound soil lichen growth forms were found indicative of habitat disturbance largely caused by grazing induced trampling. Terricolous lichen diversity of the area was delimited by grazing pressure at mid-altitudes (3,000–3,400 m) and by decreasing soil cover at higher altitudes (>3,400 m).

A mussel watch in the Ria Formosa lagoon Programa de vigilancia de mejillones en la Ría Formosa

by Michele Morgado

Diversity and distribution of terricolous lichens as indicator of habitat heterogeneity and grazing induced trampling in a temperate-alpine shrub and meadow

by Himanshu Rai

Himanshu Rai, D. K. Upreti and Rajan K. Gupta

Lichens are among the most sensitive biomonitors of ecosystem health and human induced disturbances. Terricolous... more Lichens are among the most sensitive biomonitors of ecosystem health and human induced disturbances. Terricolous lichens of Chopta–Tungnath (Garhwal, western Himalaya, India) were analysed for their ability to indicate habitat variability and disturbances induced by livestock grazing. Terricolous lichens were sampled from 12 sites, distributed across the three macrohabitats between 2,700 and 4,001 m, using 50 × 10 cm narrow frequency grids having five 10 × 10 cm sampling units. The terricolous lichen community of the area constituted, 20 species belonging to 10 genera, five families and four growth forms. Altitude and relative humidity were the major habitat factors found influencing the terricolous lichen community of the landscape. Fruticose and compound soil lichen growth forms were found indicative of habitat disturbance largely caused by grazing induced trampling. Terricolous lichen diversity of the area was delimited by grazing pressure at mid-altitudes (3,000–3,400 m) and by decreasing soil cover at higher altitudes (>3,400 m).

Application and assessment of a Nutrient Pollution Indicator using eelgrass (Zostera marina L.) in Barnegat Bay-Little Egg Harbor Estuary, New Jersey

by Ben Fertig

Kennish, M.J., Fertig, B. 2012, Application and assessment of a Nutrient Pollution Indicator using eelgrass (Zostera marina L.) in Barnegat Bay–Little Egg Harbor Estuary, New Jersey, Aquatic Botany 96: 23-30.
DOI: 10.1016/j.aquabot.2011.09.005

Eutrophication degrades numerous estuaries worldwide and a myriad of assessment metrics have been developed. Here, we... more Eutrophication degrades numerous estuaries worldwide and a myriad of assessment metrics have been developed. Here, we apply an example of a previously developed metric (Lee et al. 2004) designed to indicate incipient estuarine eutrophication to validate this technique in an already eutrophic estuary end-member, Barnegat Bay-Little Egg Harbor, New Jersey. The metric, termed ‘Nutrient Pollution Indicator’ (NPI) uses eelgrass (Zostera marina L.) as a bioindicator and is calculated as the ratio of leaf nitrogen content (%N) to area normalized leaf mass (mg dry weight cm-2). Eelgrass samples were collected along the entire length of the Barnegat Bay-Little Egg Harbor from June to October 2008 to determine if leaf chemistry and morphology reflect eutrophication status and a north-south gradient of nitrogen loading from the Barnegat Bay watershed. Nitrogen content, area normalized leaf mass, and NPI values all significantly (p < 0.05) varied temporally but not spatially. NPI values did not significantly correspond to the north-south gradient of nitrogen loading from the Barnegat Bay watershed. The NPI metric is therefore not deemed to reliably indicate estuarine eutrophic status. Differences between sampling effort (number of stations) and replication did not bias the overall conclusions.

What can a sessile mollusk tell about neotectonics?

by Christophe Morhange

Earth and Planetary Science Letters 296 (2010) 451–458

Dendropoma petraeum are fixed vermitids (mollusk) that colonize and construct abrasion platform rims
along rocky... more Dendropoma petraeum are fixed vermitids (mollusk) that colonize and construct abrasion platform rims
along rocky shorelines. These endemic mollusks are considered good relative sea level indicators in the
eastern and the southern Mediterranean, due to their narrow habitat below the sea surface (about ±10 cm).
The observed relative sea level values recorded (submerged, uplifted or at present mean sea level) reflect a
superposition of eustatic, isostatic, tectonic and possibly local sedimentary instabilities. The present study
examines fossil Dendropoma samples gathered along the Levant coast, from northern Israel to eastern
Turkey. Conventional radiocarbon dates (from Turkey, Syria and partly in Lebanon) and 14C Accelerator
Mass Spectrometer (AMS) from Lebanon and Israel yields Dendropoma ages ranging through Late Holocene.
A numerical model is used for calculating the change in sea level through the Holocene as a function of
glacio-hydrology and isostasy of the eastern Mediterranean. Space–time dependent subtractions of the
model values are used to eliminate the eustatic component of the relative sea level, in order to obtain the
tectonic component. Results show a general northward increase in tectonic uplift of the Levantine coast with
different rates in different tectonic segments. This differential uplift corresponds well to the major tectonic
segments comprising the Levantine continental margin since the Pleistocene, from the Carmel fault to the
East Anatolian fault. Hence, these segments were still active during the last thousands years and even during
the last hundreds years. The general trend of northward increase in vertical displacement is predominantly
dictated by the convergence between the Sinai and Arabian plates with Anatolia and Eurasia, across the
Cyprus arc and Zagros belt; and the secondarily dictated by the northward increase in convergence
component across the sinistral Dead Sea Fault plate boundary.

Berthon V., Bouchez A. & Rimet F., 2011. Using diatom life-forms and ecological guilds to assess organic pollution and trophic level in rivers: a case study of rivers in south-eastern France. Hydrobiologia, 673: 259–271.

by Frederic Rimet

Do fallen fruit-dwelling chironomids respond to stream riparian degradation?

by Tadeu Siqueira

Published in Pan-American Journal of Aquatic Sciences, 4, 357-362, 2009.

Tropical streams host intriguing interactions between fruits and fruit-eating insects. However, there is little... more Tropical streams host intriguing interactions between fruits and fruit-eating insects. However, there is little information on the impacts of deforestation on the aquatic insects associated with fallen-fruits in Neotropical streams. Given that fallen-fruit dwelling insects may depend on the availability of fruits in streams and consequently on the riparian forest condition, we hypothesized that density of the fallen-fruit dwelling chironomid Endotribelos would differ in streams whose catchments differed in land use, particularly riparian forest conditions. To test this hypothesis we experimentally placed fruits in streams characterized by a gradient of riparian forest degradation. We applied correlation analysis between Endotribelos mean density by fruit, number of colonized fruits, and environmental variables. All results evidenced that fallen-fruit chironomid Endotribelos were affected by riparian degradation.

Rimet F., Couté A., Piuz A., Berthon V. & Druart J.C., 2010. Achnanthidium druartii sp. nov. (Achnanthales, Bacillariophyta): A new species invading European rivers. Vie et Milieu, 60: 185-195.

by Frederic Rimet

Lobo EA, Wetzel CE, Ector L, Katoh K, Blanco S, Mayama S 2010. Response of epilithic diatom community to environmental gradients in subtropical temperate Brazilian rivers. Limnetica 29: 323-340

by Saúl Blanco

This work aims to analyse the response of epilithic diatom communities to environmental gradients in subtropical... more This work aims to analyse the response of epilithic diatom communities to environmental gradients in subtropical temperate
southern Brazilian rivers to contribute to the development of a widely applicable methodology for water-quality monitoring.
Samples for physical, chemical and biological determination were collected monthly, from December 2001 to November
2002 and from March 2003 to February 2004, at 9 stations along the rivers Pardo and Pardinho in the hydrographical basin
of Rio Pardo, State of Rio Grande do Sul (RS), Brazil. Physical and chemical variables (water temperature, pH, dissolved
oxygen, biochemical oxygen demand, chemical oxygen demand, nitrates, nitrites, phosphates and total dissolved solids) and
biological variables (epilithic diatom communities) were used as parameters for water-quality assessment. The data matrix
was examined by means of a multivariate ordination using Detrended Correspondence Analysis (DCA). In total, 270 taxa
were identied to specic or infra-specic levels. The results showed that of all the physical and chemical variables used, the
main gradient along the DCA rst axis was eutrophication, which was indicated by its signicant correlation with phosphates
( p < 0.001). Hence, the species’ scores on the DCA axis were used as an operational criterion for indicating their tolerance to
eutrophication. From this analysis, the 10 taxa that were the most tolerant to eutrophication were: Cyclotella meneghiniana,
Fallacia monoculata, Nitzschia acicularis, N. clausii, N. nana, N. palea, Nitzschia sp., Pinnularia sp., Sellaphora pupula
sensu lato and Ulnaria acus. The present study showed that epilithic diatom assemblages reect anthropogenic changes in
hydrographic basins in subtropical temperate streams, especially pollution by organic enrichment and eutrophication.

Cejudo-Figueiras C, Morales EA, Wetzel CE, Blanco S, Hoffmann L, Ector L 2010. Analysis of the type of Fragilaria construens var. subsalina (Bacillariophyceae) and description of two morphologically related taxa from Europe and the United States. Phycologia 50: 67-77

by Saúl Blanco

Fragilaria construens var. subsalina is a common diatom found in a wide variety of aquatic systems worldwide. It was... more Fragilaria construens var. subsalina is a common diatom found in a wide variety of aquatic systems worldwide. It was described by Hustedt (1925) from brackish waters in Oldesloe, Germany; a lectotype specimen was established by Simonsen (1987). We analysed the ultrastructure of specimens from the lectotype material by means of light (LM) and scanning electron microscopy (SEM) and show that this taxon should be placed at the species level within the genus Pseudostaurosira (as Pseudostaurosira subsalina). A similar but distinct taxon from the United States, found in waters with low electrolyte content, is proposed as a new species of Pseudostaurosira, namely Pseudostaurosira americana sp. nov. We also describe a second new species from Spain (Pseudostaurosira alvareziae sp. nov.), found in waters with moderate conductivity, which was misidentified as P. subsalina in the past. A morphometric analysis of the valve shape supports the morphological separation between the three species. The present study clarifies the taxonomy, ecology and systematic position of these three taxa and provides a comparison with other, similar taxa.

Cejudo-Figueiras C, Blanco S, Álvarez-Blanco I, Ector L & Bécares E 2010. Nutrient monitoring in spanish wetlands using epiphytic diatoms. Vie et Milieu / Life & Environment 60: 89-94

by Saúl Blanco

The Water Framework Directive requires that the European Union countries
determine the biological state of their... more The Water Framework Directive requires that the European Union countries
determine the biological state of their waters with respect to sites of high quality. Although bioindicators
have been widely applied in running waters and deep lakes throughout Europe, little
is known about their applicability in shallow lakes and wetlands. The objective of this work is to
check the effectiveness of epiphytic diatoms as indicators of the trophic state in two wetlands of
Álava Province (N Spain). Diatom and water chemical samples were collected during summer
and autumn 2007, following standard methodology. Stems of submerged macrophyte (Carex
riparia, Iris pseudacorus, Veronica anagallis-aquatica) were sampled in each lake. Based on
the number of statistically significant correlations between diatom indices and environmental
factors, the SID index was show as the most suitable method to assess nutrients within these
systems. SID was significantly correlated with TP, NTK and ammonium levels. Among three
different plants, only the indices calculated from I. pseudacorus samples were significantly correlated
with nutrients.

Álvarez-Blanco I, Cejudo-Figueiras C, Bécares E, Blanco S. 2010. Spatiotemporal changes in diatom ecological profiles: implications for biomonitoring. Limnology. DOI 10.1007/s10201-010-0333-1

by Saúl Blanco

Diatom indices developed in certain geographic
regions are frequently used elsewhere, despite the strongmore Diatom indices developed in certain geographic
regions are frequently used elsewhere, despite the strong
evidence that such metrics are less useful when applied in
regions other than that where species–environment relationships
were originally assessed, showing that species
have particular autoecological requirements in different
geographic areas. In this study, we define the ecological
profiles for selected environmental variables in three
common epilithic diatom species in the Duero Basin (NW
Spain), comparing our results with data gathered from
different geographic regions. We assess differences in
autoecological parameters obtained from the northern and
southern subbasins, and from different years, in order to
observe whether significant small-scale, spatiotemporal
changes exist. Our results show that there are variations
in species’ autoecological parameters between different
regions. Furthermore, there are significant changes comparing
northern and southern Duero subbasins for certain
species and physiochemical variables. Additionally, different
autoecologies have been observed for certain diatoms
and environmental factors comparing two different
years. It can be concluded that freshwater diatom autoecologies
can vary between different geographic areas. This
implies that, in order to improve water-quality bioassessments,
autoecology-based diatom metrics should be
developed by quantifying species distributions along
environmental gradients, using datasets representative of
the areas or river types where the metrics will be applied.

Cejudo-Figueiras C, Álvarez-Blanco I, Bécares E, Blanco S. 2010. Epiphytic diatoms and water quality in shallow lakes: the neutral substrate hypothesis revisited. Mar. Freshwat. Res. 61: 1457-1467

by Saúl Blanco

For bioassessment of freshwaters, diatom indices have been mainly used in streams although their applicability in... more For bioassessment of freshwaters, diatom indices have been mainly used in streams although their applicability in shallow lakes has been demonstrated in several studies. However, the influence of sampling substrata on periphytic diatom communities and on the ecological quality inferred from them has been paid little attention. In this paper, we test the ‘neutral substrate hypothesis’, which predicts no relevant influence of host plant type on their epiphytic community. Nineteen shallow permanent lakes from north-west Spain were studied and classified into three trophic levels. Epiphytic diatom communities growing on three different macrophytes for each trophic level were sampled and analysed. We assess: (1) which of the most common diatom indices provides a reliable water quality assessment, (2) how different plant substrata influence the diatom communities growing on them and (3) how these differences affect water quality assessment. Similarity tests showed significant differences in the composition of diatom assemblages among nutrient concentrations and host macrophytes. In contrast, ANOVA results for selected diatom-based metrics showed significant differences among trophic levels but not between different plant substrata. This supports the use of epiphytic diatoms as biological indicators for shallow lakes irrespective of the dominant macrophyte.

Bérard A., Rimet F., Capowiez Y. & Leboulanger C., 2004. Procedures for determining the pesticide sensitivity of indigenous soil algae - a possible bioindicator of soil contamination? Archives of Environmental Contamination and Toxicology, 46: 24-31.

by Frederic Rimet

Rimet F., Ector L., Hoffmann L., Gevrey M., Giraudel J.L., Park Y.S. & Lek S., 2005. Prediction with artificial neural networks of diatom assemblages in headwater streams of Luxembourg. In Lek S., Scardi M., Verdonschot P.F.M., Descy J.-P., Park Y.S. (eds), Modelling community structure in aquatic ecosystems. Springer Verlag, 343-354.

by Frederic Rimet

Rimet F., Cauchie H.M., Tudesque L. & Ector L., 2005. Use of artificial intelligence (MIR-max) and chemical index to define type diatom assemblages in Rhône basin and Mediterranean region. In Lek S., Scardi M., Verdonschot P.F.M., Descy J.-P., Park Y.S. (eds), Modelling community structure in aquatic ecosystems. Springer Verlag, 288-303.

by Frederic Rimet

Rimet F., Ciutti F., Cappelletti C. & Ector L., 2005. Ruolo delle Diatomee nell’applicazione della Direttiva Europea Quadro sulle acque. Biologia Ambientale, 19: 87-93.

by Frederic Rimet