Extant Water Research Articles

Chromium "(VI)" phytoremediation using Azolla pinnata: effects on Vicia faba growth, physiology, cytogenetics, and gene expression profiling

BackgroundOne of the primary challenges that the expanding population faces is water scarcity. Thus, a global imperative has been established to safeguard extant water resources and optimize their utility through sustainable practices and efficient management. In the present investigation, Azolla pinnata, a pteridophyte (fern), was employed to phytoremediate Cr (VI) from chromium-polluted water. The potential of this treated water for agricultural purposes was verified through the use of Vicia faba plants.ResultsIn vitro, A. pinnata effectively remediates Cr (VI) from an array of liquid concentrations (0.05 to 90 ppm) in a ratio of 25:1 {volume (mL): fresh weight of Azolla (g)} after 2 days incubation period at room temperature. At low concentrations (0.1 ppm), the phytoremediation capacity peaked at 70%, falling to 19.53% at a high concentration (90 ppm). Upon continuous irrigation with Cr-polluted water (0.05 to 50 ppm), the in vivo pot experiment on Vicia faba plants revealed high Cr accumulation in the roots reached 52.5 mg Kg-1 dry weight (Dwt) at the 50 ppm Cr treatment. Nevertheless, a reduced Cr content of 19.5 mg Kg-1 Dwt was observed when the plants were irrigated with 50 ppm Cr-polluted water that had been treated with Azolla. At 50 ppm of Cr, Azolla's treatment significantly increased shoot length, fresh weight, and Chl a content to 25.25 cm, 3.4 g, and 6.5 mg g-1 Dwt, respectively, up from 10.25, 1.8, and 4.7 in untreated plants. The chromosomal aberrations were significantly induced in the dividing cells of all Cr treatments, with the highest value of 4.8% at 50 ppm. This value was reduced to 2.88% at the same concentration when treated with Azolla. At a concentration of 10 ppm Cr, the mitotic index was significantly improved to 6.99% when combined with Azolla, as opposed to 3.63% when the same concentration was used without Azolla. The DNA degradation assay showed partial DNA degradation at 50 ppm Cr, which the Azolla treatment eliminated. Furthermore, the gene expression levels of both the PM H+-ATPase and the calcium-dependent protein kinase CDPK5 were upregulated in response to Cr, despite the fact that the expression level was altered in a dose- and concentration-dependent manner by Azolla treatment.ConclusionAzolla exhibits substantial potential for reducing the detrimental effects of chromium stress including oxidative stress on plants. It modulates stress-related gene expression, protects DNA integrity, enhances cell mitosis, and reduces chromosomal damage. These results indicate that Azolla has the potential to be a valuable asset in phytoremediation strategies for chromium-contaminated environments, and that it may enhance plant survival and growth under Cr stress conditions.Key messageAzolla pinnata can be effectively utilized as an environmentally-friendly method to remediate chromium-contaminated water for agricultural usage.

Cranial ontogenetic development and sexual dimorphism of the extant water chevrotain Hyemoschus aquaticus

AbstractTragulids or mouse-deer live in tropical Asia and Africa. They are the sister group of Pecora and have a long fossil record dating back into the Eocene. The extant African species, Hyemoschus aquaticus, is the sister taxon of all other extant tragulids and is therefore often used for comparison with fossil mouse deer. However, although many fossil tragulid skulls were found and studied within the last years, no attempt has been made for a comprehensive and comparative study of the ontogenetic development of cranial sexual dimorphism of H. aquaticus. Based on 39 extant skulls we establish an ontogenetic categorization of this species, comprising nine stages of tooth wear. We show that (I) in H. aquaticus upper canine development remains the main character for distinction of male and female, (II) that the eruption of the permanent upper canines and the development of sagittal crests starts before sexual maturity after the eruption of the second upper molar, and (III) that the development of further cranial crests (nuchal crests, temporal lines) varies greatly within the same age class and among the sexes. Thus cranial ornamentation is not useful as a primary distinction feature between the sexes and of limited importance in identifying ontogenetic age. The newly established categories of wear stages and the observed sexual similarity in cranial crest development can be used in future comparative studies with the other extant mouse-deer and especially with their fossil representatives.

Spectroscopic identification of water emission from a main-belt comet.

Main-belt comets are small Solar System bodies located in the asteroid belt that repeatedly exhibit comet-like activity (that is, dust comae or tails) during their perihelion passages, strongly indicating ice sublimation1,2. Although the existence of main-belt comets implies the presence of extant water ice in the asteroid belt, no gas has been detected around these objects despite intense scrutiny with the world's largest telescopes3. Here we present James Webb Space Telescope observations that clearly show that main-belt comet 238P/Read has a coma of water vapour, but lacks a significant CO2 gas coma. Our findings demonstrate that the activity of comet Read is driven by water-ice sublimation, and implies that main-belt comets are fundamentally different from the general cometary population. Whether or not comet Read experienced different formation circumstances or evolutionary history, it is unlikely to be a recent asteroid belt interloper from the outer Solar System. On the basis of these results, main-belt comets appear to represent a sample of volatile material that is currently unrepresented in observations of classical comets and the meteoritic record, making them important for understanding the early Solar System's volatile inventory and its subsequent evolution.

Determining the effect of mineral scaling formation under different injection water sources on the performance of Mishrif carbonate reservoir in Halfaya oilfield, Southern Iraq

The chief source of the oilfield scale is the mixing of incompatible waters. This study demonstrated that mixing the reservoir of Mishrif formation (Halfaya oilfield) with six types of injection water sources, including Tigris River water, producing water formation, Gulf seawater, Marshes water, Middle Kirkuk formation water, and Main Outfall Drain water (AL-Masab AL-Aam Channel), leads to the formation of salt crusts that cause the reduction of reservoir rock permeability. According to the Piper diagram, the Mishrif formation water of all extant water samples was of the sodium chloride type (NaCl), except for HF-81, which was between (NaCl) and mix (CaMgCl) type. A geochemical simulation model of water alignment (PHREEQC) was used to simulate this problem, and it revealed the mineral scaling from mixing processes. These minerals precipitate in rock pores and clog them, which then cause damage to the petrophysical properties of the reservoir and prevent the passage of liquids. Results showed that the best water types used for injection are Middle Kirkuk formation water, followed by the general downstream, then Gulf seawater, but treatment before injection is needed. The study of geochemical modeling method can help to better understand scaling issues by efficiently identifying the best injection water from various selected types with the lowest possible cost, which in turn improves oil production.

Extensive glaciation in the Erebus Montes region of Mars

Lobate debris apron (LDA) in the Mars' mid-latitudes substantiate extensive glaciation during the Late Amazonian. Detailed investigation of these landforms is imperative because different areas distributed at different latitudes, distinct geologic settings and varied regional topography may have responded to climate in different ways. In this study, mapping of LDA deposits in Erebus Montes region in the flat, low-lying plains of the northern mid-latitudes has been undertaken and examined at a detail previously not attempted to infer new insights on the history of extensive glaciation. LDA deposits show convex-up, steep terminus profiles consistent with typical down-gradient flow characteristics, and integrated flow patterns akin to the glacial landforms reported along the dichotomy boundary. Evidence for a broad piedmont-like lobe, down-gradient flow within a possible oblique-impact crater, and infilled craters, suggest focused localized flow and glaciation. Lobate flows emanating from small alcoves and superposed on the main LDA are not observed, which likely suggests that there is a lack of multi-stage glaciation facilitated by the alcove microclimatic conditions in the region. Linear-curvilinear ridges on the LDA deposits could be the remnant of the internal flow lineations, and are most likely produced by the sublimation of debris-rich ice. Brain-terrain textures, polygonal cracks and ring-mold craters are ubiquitous on the upper surface of LDA deposits, which provides the morphological evidence for the past accumulation of LDM in the region. Hitherto, radar-based investigations do not provide substantial evidence for the presence of extant water ice beneath LDA deposits. We find that the LDA deposits examined here are more consistent with the cold-based glacial behavior - morphological observations supports existence of the sublimation process in the region. We suggest that the derived best-fit age of ~30 Ma for the LDA deposits indicates age of the debris apron that has been mantled and the mapped LDA deposits in our study should be better represented by a broad age range of ~10–100 Ma. Together, our findings add another well-documented case to support the rapidly accumulating evidences for widespread extensive debris-covered glacial landsystems in the northern mid-latitudes of Mars in the Late Amazonian geological history.

Localizing the Human Right to Water in Lagos State, Nigeria

Nigeria’s water sector is characterised by abysmal network coverage despite significant natural water resources potential. Most of the water sector reforms across the country encourage private sector participation in service delivery, to improve quality and efficiency. Early attempts at water privatization in Lagos State, a pioneer for water sector reforms in Nigeria, have met with stiff opposition from local water justice advocates, mostly on human rights grounds. Similar opposition has followed water reforms and privatization efforts in other parts of the country as well. Hence, this paper uses Lagos State as a case study to examine the prospects for the localisation of the human right to water within the context of private sector participation in the water sector. The findings suggest that: (a) private sector participation solely cannot account for the failure to localize the human right to water and the legal framework regulating the water sector plays an important role in determining the outcome; (b) the extant water sector law in Lagos State entrenches various forms of inequality in water access for personal and domestic uses; and (c) there is need for further legal reforms to elevate access to safe drinking water services beyond the contractual obligation on consumers to pay for services to a human right.

Greater effect of warming on community composition with increased precipitation and in moister landscape location

AbstractQuestionsWe asked how plant community composition responded to experimentally produced warmer and drier climate conditions at the landscape scale with existing variation in local species composition and environmental conditions. We aimed to identify changes in community composition overall and the species with greatest response in abundance, and hypothesized that locally restricted species may be more sensitive to warming than more widespread species within the landscape based on the assumption that they have a narrower niche breadth with respect to environmental conditions.LocationSemiarid, northern Mongolian steppe.MethodsOpen‐top passive warming chambers (OTCs) elevated temperatures at two slope locations that differed in elevation, degree of slope, environmental conditions, and species composition. The OTC treatment was crossed with watering on the drier upper slope. Community composition differences among treatments were examined using canonical analysis of principal coordinates (CAP), which identified species contributing the most to differences. In response to warming, we also compared species locally restricted to one slope location with locally widespread species.ResultsOpen‐top passive warming chambers affected community composition more where soil moisture was greater, at the lower slope location and where warming was combined with supplemental watering on the drier upper slope. Locally restricted species responded negatively to the OTC while locally widespread species showed no overall response.ConclusionsCommunity composition responses to warming differ even within the landscape over and above the initial differences that exist in community structure and abiotic factors. Our results suggest that a warmer and drier climate will impact community composition sooner under more mesic conditions, affect locally restricted species more strongly, and reduce variation in species composition across the landscape. To better predict community responses to future warming, we must consider combined and interactive effects with changes in precipitation and extant water availability.

Designing and modeling innovation across scales for urban water systems

Effective, sustainable management of urban water systems, including drinking water, stormwater, wastewater, and natural water systems, is critical to the health and well-being of people in urban areas and the ecosystems that encompass them. The demands of human population growth, aging infrastructure, and changing climate will increase pressure on these systems and require future innovations in water management. Planning for urban water systems will increasingly require collaborations between water professionals and researchers to imagine, design and model the response of novel urban water systems to future conditions. We highlight benefits and challenges of transdisciplinary projects for integrated urban water management; organized broadly into: (1) engagement of water managers and planners; (2) transdisciplinary design of innovative systems, and once designed; (3) modeling and evaluation of urban water system response to various innovations. We describe the development of a multi-scale approach to design and evaluation of innovative urban water systems, and illustrate its application using examples from the Willamette River Basin and Portland, Oregon. The scenario-based approach described here offers several key contributions to the design and modeling of innovation. First, this process provides the opportunity to convene professionals and researchers, who do not typically collaborate, as participants in a collaborative process. Second, it engages participants in thinking together across land and water management sectors to develop plausible futures at multiple spatial extents and multidecadal time horizons. Third, it helps to identify critical gaps in extant water modeling capabilities, and thus helps define the near-term research agenda for modelers.

Political economy of water reallocation in South Africa: Insights from the Western Cape water crisis

The severity of the recent drought combined with significant population pressure in the Western Cape Province has exposed flaws within extant water resource governance structures and institutional arrangements in South Africa. Equity driven water (re)allocations are at the heart of post-Apartheid water reform and have become a highly contested space within and between rural and urban spheres. Equity-efficiency trade-offs are simultaneously the primary driver of and barrier to effective reallocation, closely interwoven with centralised institutional structures and the disjuncture between policy and legal reallocation objectives. This analysis highlights the risks associated with not addressing reallocation challenges. Thus, providing insight into the nuanced yet critical role reallocation can play in maximising benefits associated with managing water and development across increasingly integrated rural-urban systems.

Transported zooplankton from the Okhotsk Sea facilitate feeding and growth of juvenile walleye pollock on a continental shelf along the Oyashio Current, western subarctic Pacific

The advective transport of zooplankton provides an important source of energy on continental shelves. On a continental shelf along the Oyashio Current, western subarctic Pacific (42°30′N, 144°00′E), the extant water mass is replaced biannually by inflows of water masses from the highly productive Okhotsk Sea. These inflows and accompanying zooplankton are hypothesized to enhance biological production on the shelf. In this study, seasonal feeding and growth of a juvenile planktivorous fish, walleye pollock (Gadus chalcogrammus), on the shelf were examined in relation to water mass exchanges from September 2003 to June 2005. Zooplankton were sampled from February to April in 2004 and 2005, and in April 2014 and 2015. Juvenile pollock frequently consumed an Arctic copepod, Calanus glacialis, and a boreal euphausiid, Thysanoessa inermis, after January when the shelf was occupied by cold water masses that originated from the southwestern Okhotsk Sea. Juvenile pollock whose diet contained higher contributions of these energy-rich prey items exhibited positive growth in February–March 2005, whereas fish with lower proportions of these prey exhibited little growth during this period in 2004. The winter distributions of the copepod and euphausiid extended from a continental slope area in the southwestern rim of the Okhotsk Sea to the shelf along the Oyashio Current. Together, these results suggest the transport of zooplankton from the Okhotsk Sea likely influences the biological production of the coastal Oyashio ecosystem by enhancing the availability of energy-rich prey for juvenile pollock.

First evidence of insect herbivory on Albian aquatic angiosperms of the NE Iberian Peninsula

ABSTRACTEvidence of herbivory on Laurasian Nymphaeaceae leaves from Lower Cretaceous (Upper Albian) deposits is presented for the first time. The types of damage on leaves consist of both hole feeding and margin feeding, which were found on foliar remains of the taxa Ploufolia cerciforme and Aquatifolia cf. fluitans. Within the first category of damage, the Damage Type 78 (DT78) type on Ploufolia leaves and type DT02 on Aquatifolia foliar lamina were recorded. The second category of damage has only been identified in Ploufolia leaves, and it corresponds to type DT12. The subsequent palaeoichnologic interpretation made it possible to compare these records with damage caused by the extant water lily pest to make a possible palaeoecological interpretation.

Deficit irrigation with reclaimed water in a citrus orchard. Energy and greenhouse-gas emissions analysis

Irrigated agriculture brings important socio-economic benefits, but requires high energy consumption, which in turn generates environmental problems by emissions of greenhouse gases. To maintain agricultural activity in the Segura River Basin in the face of extant water shortages, farmers are increasingly using non-conventional water resources such as reclaimed water, and implementing water conservation techniques such as regulated deficit irrigation. The present study quantified the energy consumption and production and greenhouse gas emissions of a grapefruit orchard under the implementation of two irrigation regimes (full and regulated deficit irrigation) and the alternative use of reclaimed water instead of water transferred from the Tajo-Segura Basin for irrigation. The study additionally included the novelty of performing the analyses considering four different stages of crop development. The energy and the greenhouse gas emissions assessment was performed for each study case based on an inventory of inputs of the selected plot and their corresponding energy conversion and greenhouse gas factors. The results indicate that, under the conditions studied, the use of reclaimed water and/or the implementation of regulated deficit irrigation strategies had no significant effect on energy productivity and specific greenhouse gas emissions, irrespective of the stage of crop lifecycle analysed. Moreover, in order to increase the energy efficiency of the orchard and reduce greenhouse gas emissions, the energy consumption associated with the transportation of water to the plot, the manufacture of the irrigation system and the manufacture and transport of fertilisers should be reduced.

Determination and distribution of region-specific background Secchi depth based on long-term monitoring data in the Seto Inland Sea, Japan

Secchi depth has traditionally been used to assess the light transmittance of a water body and to indicate the degree of eutrophication. Anthropogenic eutrophication can decrease Secchi depth by increasing phytoplankton density. However, Secchi depth is determined not only by phytoplankton density but also by suspended particulate matter, chromophoric dissolved organic matter, and by the optical properties of the seawater itself. These latter factors contribute to a region-specific component of the Secchi depth that is independent of phytoplankton density. The present study aims to estimate this region-specific Secchi depth component, which we term the background Secchi depth (BSD). We compared measured Secchi depth for the past 10 years against BSD to understand the optical condition of extant water bodies and the limits of anthropogenic nutrient reduction as a method of increasing the Secchi depth. Our study analyzed 34 years of seasonal monitoring data across 124 sites in the Seto Inland Sea, Japan. BSD was obtained in 67% and 63% of the sites in the spring and summer, respectively, and 37% and 19% of the sites in autumn and winter. High turbulence during the autumn and winter caused unstable background light attenuation, making it difficult to determine an accurate BSD in many sites. BSD was positively correlated with salinity and water depth and could be estimated from these two parameters. Low BSD was observed near the shore and at shallow sites. Measured Secchi depths over 30% smaller than BSD were observed from 20% to 48% of the sites in 1981–1990, those observations were reduced to 4% to 9% of the sites in the past 10 years (2005–2014), indicating that the impact of eutrophication on light transmittance is not severe at present. Consequently, further reduction of anthropogenic nutrient loads will have a limited effect on Secchi depth in many areas. Moreover, we show the existence of a greater discrepancy between measured Secchi depth and BSD in warm seasons than in cold seasons. Similarly, the difference between measured Secchi depth and BSD was higher in geographically enclosed sub-basins than in other sub-basins.

Spatial evaluation of appropriate areas to collect runoff using Analytic Hierarchy Process (AHP) and Geographical Information System (GIS) (case study: the catchment “Kasef” in Bardaskan

Collecting runoff is used to minimize losses and strengthening water reserves (water resources) in the system of catchments. Identifying suitable locations to collect runoff is an important step towards maximizing water availability and optimal utilization of agricultural land in semi-arid areas. Collecting rainwater and runoff is of measures that can be effective in proper utilization of water available in arid areas. Using traditional Knowledge, constructional skills, and local resources and due to geographical and climate conditions, water collection systems are expanded as a means of extant water supply in different areas. Nevertheless, regardless of indirect impacts on downstream hydrological and ecological systems, methods of collecting runoff are needed to understand better the environmental and hydrological effects of catchment system. For the purpose of spatial evaluation of suitable areas to collect runoff in the catchment “Kasef” in Bardaskan, runoff values are first calculated using the model of curve number and the maps of land use, hydrologic groups of soil, runoff production potential, the distance from both the arable lands and residential area are thereafter prepared in the environment of Arc-GIS 9.3 software. Then, they are weighted using Analytical Hierarchy process (AHP) based on the questionnaire forms and the expert choice 11 software and the relative importance of each of the main criteria and their classes are calculated. So the maps are finally combined in Arc-GIS software to determine the convenient localities of collecting runoff. The results showed that, amongst several criteria, according to expert opinions the criterion of runoff potential has allocated the utmost relative importance to assess susceptible areas for collecting runoff. Also, 2.35 % and 114.68 hectares of the catchment area “Kasf” has a very high potential for runoff production and 12.27 % and 598.11 hectares of this catchment has a high potential and 48.66 % and 2371.62 hectares has a very low potential. It was also noticed that 12.39 % and 603.78 hectares of the catchment area “Kasef” has a very high proportion and 0.41 % and 20.14 hectares has a high proportion and 6.89 % and 335.8 hectares has a very low proportion for the susceptible areas to collect runoff. We can finally say that spatial evaluation and identification of suitable areas to collect runoff is an important and necessary step in applying and developing runoff collecting systems in each system of catchments.

Enigmatic affinity in the brain morphology between plotopterids and penguins, with a comprehensive comparison among water birds

Plotopterids (Aves: Plotopteridae) are extinct flightless birds that were endemic to the North Pacific Ocean. As flightless, wing-propelled diving birds they exhibit similar skeletal morphology to Sphenisciformes (penguins), especially in their wings. In contrast to the similarity, Plotopteridae have been placed in (traditional) Pelecaniformes in most palaeontological and phylogenetic studies, based on shared characters that are absent in penguins. The postcranial morphology of Plotopteridae has been well studied, but little is known about the cranial morphology, particularly the nervous system. The brain morphology of Plotopteridae, compared with other water birds, could prompt a reconsideration of those previous phylogenetic hypotheses, as the cranial morphology is conservative and could provide powerful signals for the phylogenetic reconstruction. In order to compare the brain morphology of Plotopteridae with that in other water birds (Ciconiiformes, Pelecaniformes, Suliformes, Procellariiformes, and Sphenisciformes), we generated virtual endocasts of Plotopteridae and extant water birds. We investigated the brain morphology of those birds using three-dimensional geometric morphometric and linear measuring methods. The width of the cerebellum and the length of the floccular lobe varied considerably among water birds, and the relative lengths separate Procellariiformes + Sphenisciformes from Ciconiiformes + Pelecaniformes + Suliformes. The former group had a relatively wider cerebellum and longer floccular lobe, whereas the latter group had a relatively narrower cerebellum and shorter floccular lobe. The relative width of the cerebellum and length of the floccular lobe in Plotopteridae was comparable with that of the former group, in addition to many morphological similarities to the Sphenisciformes brain. On the basis of brain morphology alone, we dare not conclude that Plotopteridae forms a clade with, or belongs to, Sphenisciformes; however, the brain configuration of Plotopteridae is distinctly close to that of penguins, and could possibly reflect their phylogenetic relationship. © 2013 The Linnean Society of London

Enigmatic affinity in the brain morphology between plotopterids and penguins, with a comprehensive comparison among water birds

Plotopterids (Aves: Plotopteridae) are extinct flightless birds that were endemic to the North Pacific Ocean. As flightless, wing-propelled diving birds they exhibit similar skeletal morphology to Sphenisciformes (penguins), especially in their wings. In contrast to the similarity, Plotopteridae have been placed in (traditional) Pelecaniformes in most palaeontological and phylogenetic studies, based on shared characters that are absent in penguins. The postcranial morphology of Plotopteridae has been well studied, but little is known about the cranial morphology, particularly the nervous system. The brain morphology of Plotopteridae, compared with other water birds, could prompt a reconsideration of those previous phylogenetic hypotheses, as the cranial morphology is conservative and could provide powerful signals for the phylogenetic reconstruction. In order to compare the brain morphology of Plotopteridae with that in other water birds (Ciconiiformes, Pelecaniformes, Suliformes, Procellariiformes, and Sphenisciformes), we generated virtual endocasts of Plotopteridae and extant water birds. We investigated the brain morphology of those birds using three-dimensional geometric morphometric and linear measuring methods. The width of the cerebellum and the length of the floccular lobe varied considerably among water birds, and the relative lengths separate Procellariiformes + Sphenisciformes from Ciconiiformes + Pelecaniformes + Suliformes. The former group had a relatively wider cerebellum and longer floccular lobe, whereas the latter group had a relatively narrower cerebellum and shorter floccular lobe. The relative width of the cerebellum and length of the floccular lobe in Plotopteridae was comparable with that of the former group, in addition to many morphological similarities to the Sphenisciformes brain. On the basis of brain morphology alone, we dare not conclude that Plotopteridae forms a clade with, or belongs to, Sphenisciformes; however, the brain configuration of Plotopteridae is distinctly close to that of penguins, and could possibly reflect their phylogenetic relationship. © 2013 The Linnean Society of London

Legislating for sustainable basin management: the story of Australia's Water Act (2007)

Australia's Millennium drought, a 13-year dry period unprecedented in the instrumental record, inspired a change in the extant water management principles. The Water Act of 2007 was introduced and required the preparation of a Basin Plan to set environmentally sustainable levels of water extraction and to reduce the over-allocation of water entitlements that threatened water security. The Act was unusual in that environmental considerations were initially interpreted as a non-negotiable constraint on other water uses because of the legislative context in which it was written. This framing shaped subsequent negotiations during development of the Basin Plan. The recent passing of this Plan into law provides a conclusion to this complex, messy and, at times, irrational reform process. The path taken, from genesis of the Act to its eventual culmination in the Basin Plan, provides internationally important lessons in legislating for sustainable water management in inter-jurisdictional river basins. However, the reforms have also created new opportunities for ongoing improvement, including the mutual benefits derived from managing environmental water and irrigation water cooperatively.

Can the substructure of fossil feathers provide taxonomic information?

In the study reported here we explore a method for extracting information on the identity of fossil bird families from the fossil feather substructure and their possible taxonomic association with extant bird families. Such information can serve as an ecological indicator of the paleo-environment from which the fossil feathers have originated. It has been established that the balance between the water repellency and the resistance to water penetration of feathers can provide taxonomic information on bird families. These properties of feathers can be determined from the diameter of the barbs and their spacing, and their values correlate to the behavior/habitats of a large variety of families, particularly water bird families. The observed relationship between feather structure and habitat/behavior in extant water birds equally applies to fossil feathers and hence offers taxonomic clues about its avian bearer. The method is most productive for body feathers and limited to fossils of sufficient quality to permit evaluation in terms of barb diameter and spacing. The fossil feather collections of the Paleo-biology section of the Smithsonian Institution, Washington DC and the Senckenberg Research Institute and Natural History Museum, Frankfurt a/M were examined, and those specimens most amenable to quantitative evaluation were measured. The family relation of several specimens could be independently verified by the presence of additional anatomic material.

Middle Miocene tragulid remains from Abocador de Can Mata: The earliest record of Dorcatherium naui from Western Europe

In the past, the tragulid species Dorcatherium crassum has been considered a synonym of Dorcatherium naui, although they are currently considered distinct species. The former has an exclusively Aragonian (MN4 to MN6) stratigraphic range, whereas D. naui is considered a typically Vallesian species (MN9 and MN10) that survives until the Turolian (MN11). There are only a few previous citations of Dorcatherium from the European latest Aragonian (MN7+8), and only that of Przeworno (Poland) can be securely attributed to D. naui. Here we describe dentognathic and postcranial remains of Dorcatherium from several localities from the stratigraphic series of the Abocador de Can Mata (ACM), in els Hostalets de Pierola (Vallès-Penedès Basin, Catalonia, Spain). These Dorcatherium remains, from both the lower (ca. 11.9-12.5 Ma, MN7) and upper (ca. 11.6 Ma, MN8) portions of the ACM series, constitute the earliest record of D. naui from the Iberian Peninsula and Western Europe. They most closely resemble D. naui from the Vallesian, but still share several features with D. crassum. On the basis of the unique combination of features displayed by the ACM material, a new subspecies, D. naui meini is erected. Its distinct status from the nominotypical subspecies, D. naui naui, is reinforced by the chronological differences between the two taxa. The morphological similarities between Dorcatherium and the extant water chevrotain ( Hyemoschus aquaticus) tentatively suggest the presence of forested and humid paleoenvironments in this area of the Vallès-Penedès Basin during the latest Aragonian. Nevertheless, Dorcatherium is very rare in ACM and displays a very patchy chronological distribution. Together with the similarly spotty distribution of both primates and castorids along the ACM series, this suggests that very humid conditions might have been only intermittently present in this area throughout the latest Aragonian.

The water mites (Acari: Hydrachnidia) of the Balkan peninsula, a revised survey with new records and descriptions of five new taxa

Based on published records and original data from recent research, a list is presented of the water mite (Acari: Hydrachnidia) fauna of the Balkan countries, i.e. Croatia, Bosnia and Hercegovina, Montenegro, Albania, Serbia, Macedonia, Bulgaria and Greece. It includes 382 species and subspecies in 77 genera and 34 families. Numerous new records for national faunas are reported, and five taxa, Sperchon pelopeius (Greece), Atractides stankovici (Croatia), Axonopsis graeca (Greece), Woolastookia minuta (Bosnia and Hercegovina, Greece) and Arrenurus ornatus graecus (Greece) are described as new to science. Atractides moniezi (Motaş, 1927) is synonymized with A. lacustris (Lundblad, 1925). The assumption of K. O. Viets (1987) that Pionopsis subruber Đ orđević, 1903 is a synonym of P. lutescens (Hermann, 1804) is confirmed. The characteristics of the water mite fauna in the treated area are briefly outlined. Additional field work is highly desirable for a more appropriate evaluation of the extant water mite biodiversity in the Balkans.