Papers by Jan-robert Baars
Bookmarks Related papers MentionsView impact
BioInvasions Records, 2022
Bookmarks Related papers MentionsView impact
FIGURES 22–26. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., larva. ... more FIGURES 22–26. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., larva. 22. Antenna. 23. Pecten epipharyngis. 24. Premandible. 25. Mandible. 26. Mentum.
Bookmarks Related papers MentionsView impact
BAARS JR 2001. Biology and laboratory culturing of the root-feeding flea beetle, Longitarsus colu... more BAARS JR 2001. Biology and laboratory culturing of the root-feeding flea beetle, Longitarsus columbicus columbicus Harold, 1876 (Chrysomelidae: Alticinae): a potential natural enemy of Lantana camara L. (Verbenaceae) in South Africa. Entomotropica 16(3):149-155. The introduced ornamental plant, Lantana camara L. (Verbenaceae), is one of South Africa’s worst invasive weeds. It has been the target of a biological control programme here for the past four decades. Although several natural enemies have been established, the level of control is considered unsatisfactory, and a number of new potential biocontrol agents are being evaluated. The flea beetle Longitarsus columbicus columbicus Harold is considered to be highly destructive, attacking the roots of lantana, a niche largely ignored by biocontrollers in the past. Little is known about this potential natural enemy, and attributes of its life history and mode of feeding are discussed. Adults feed on the leaves and deposit eggs in the ...
Bookmarks Related papers MentionsView impact
In this paper we present the first records for Ireland of Heminothrus (Capillonothrus) thori (Ber... more In this paper we present the first records for Ireland of Heminothrus (Capillonothrus) thori (Berlese, 1904) and Perlohmannia (Perlohmannia) dissimilis (Hewitt, 1908), both mites belonging to the suborder Oribatida. Both species were recovered from riparian habitats along the River Liffey in Co. Kildare and, in addition to providing number of individuals and precise location of the records, some comments on the biogeography and biology of these species are presented.
Bookmarks Related papers MentionsView impact
BioInvasions Records, 2021
Bookmarks Related papers MentionsView impact
SIL Proceedings, 1922-2010, 2008
Bookmarks Related papers MentionsView impact
Biology and Environment: Proceedings of the Royal Irish Academy, 2014
ABSTRACT Salmonid populations were sampled in 64 first- and second-order headwater streams throug... more ABSTRACT Salmonid populations were sampled in 64 first- and second-order headwater streams throughout the Republic of Ireland in 2008. Streams were selected from neighbouring sub-catchments dominated either by moorland or conifer plantations, across two soil types*peat soil and mineral soil. A range of chemical variables were measured on three occasions over the year. Brown trout and Atlantic salmon populations were quantified on a single occasion for density and biomass in each stream. Data were analysed to test the null hypothesis that neither land use nor soil type had a significant impact on fish or chemical metrics in the streams. Streams draining afforested catchments had a significantly lower pH, DpH and elevated TDOC, total phosphorus, total monomeric aluminium, ammonia and colour. Streams draining peat soil sub-catchments had significantly lower minimum pH and TON, and higher suspended solids, TDOC, ammonia, aluminium and colour. While density and biomass of brown trout were somewhat lower in afforested catchments, the difference was not significant. Densities and biomass of juvenile Atlantic salmon, however, were significantly lower in streams draining afforested catchments. Atlantic salmon also had a much lower threshold tolerance to deleterious forestry-mediated water chemistry than trout. Forestry-mediated acidification of streams apparently remains a severe threat to Atlantic salmon populations, despite the reduction of airborne sulphate pollutants, posing challenges to forest and fisheries managers.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Marine and Freshwater Research, 2015
Despite knowing that agricultural practices affect river ecosystems, studies on water quality and... more Despite knowing that agricultural practices affect river ecosystems, studies on water quality and associated hyporheic invertebrate communities are rare. Yet such knowledge is essential for sustainable use of agricultural and water resources. This study, carried out in the agricultural region of south-eastern Ireland in Spring 2007, examined the effect of water pollution on hyporheic fauna. Six river sites of known water quality were assigned to two treatments, namely, clean and polluted rivers. Two hyporheic habitats, below the wetted channel (hyporheic substream) and below the exposed gravel bank (parafluvial), were sampled within each treatment. Total invertebrate densities and richness, crustacean densities and richness, and densities of Ephemeroptera, Plecoptera and Trichoptera (EPT) were significantly reduced in polluted hyporheic and parafluvial habitats. A higher recorded concentration of nitrate in the polluted hyporheic substream habitats was a significant factor in determ...
Bookmarks Related papers MentionsView impact
Hydrobiologia, 2010
Bookmarks Related papers MentionsView impact
Hydrobiologia, 2009
Abstract Eutrophication still continues to be an issue of major concern for the protection of wat... more Abstract Eutrophication still continues to be an issue of major concern for the protection of water quality, and accordingly, the European Union Water Framework Directive has set a minimum target for all waters where ''good status'' is defined as a slight departure from the ...
Bookmarks Related papers MentionsView impact
Hydrobiologia, 2011
Bookmarks Related papers MentionsView impact
Oceanological and …, 2004
Benthic diatom samples were collected from 45 potential reference river sites in Ireland. Diatom ... more Benthic diatom samples were collected from 45 potential reference river sites in Ireland. Diatom samples were also collected from 24 lowland eutrophic sites. The main objective for sampling the potential reference sites was to determine the type-specific biological typologies ...
Bookmarks Related papers MentionsView impact
... (FORWATER) 2008 MARY KELLY-QUINN I,ROBERT CRUIKSHANKS I, JAMES JOHNSON I , ... 1990; Bowman, ... more ... (FORWATER) 2008 MARY KELLY-QUINN I,ROBERT CRUIKSHANKS I, JAMES JOHNSON I , ... 1990; Bowman, 1991; Allott et al., 1997) as well as the east have been shown to be acid-sensitive (Kelly-Quinn et al., 1996a; Kelly-Quinn, Tierney & Bracken, 1997). The potential ...
Bookmarks Related papers MentionsView impact
African Entomology, 2013
The leaf-mining fly, Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), was investigated in it... more The leaf-mining fly, Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), was investigated in its native range in South Africa, to determine its potential as a biological control agent for Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae), an invasive submerged macrophyte that is weedy in many parts of the world. The fly was found throughout the indigenous range of the plant in South Africa. High larval abundance was recorded at field sites with nearly all L. major shoots sampled ontaining larvae, with densities of up to 10 larvae per shoot. Adults laid batches of up to 15 eggs, usually on the abaxial sides of L. major leaves. The larvae mined internally, leaving the epidermal tissues of the upper and lower leaves intact. The larvae underwent three instars which took an average of 24 days and pupated within the leaf tissue, from which the adults emerged. Impact studies in the laboratory showed that H. lagarosiphon larval feeding significantly restricted the formation of L. major side branches. Based on its biology and damage caused to the plant, Hydrellia lagarosiphon could be considered as a useful biological control candidate for L. major in countries where the plant is invasive.
Bookmarks Related papers MentionsView impact
Management of Biological Invasions, 2014
Bookmarks Related papers MentionsView impact
FIGURES 17–21. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., pupa. 1... more FIGURES 17–21. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., pupa. 17. Thorax. 18. Frontal apotome. 19. Abdominal segments I–VII. 20. Abdominal segments VIII–IX. 21. Caudolateral spur.
Bookmarks Related papers MentionsView impact
FIGURES 12–16. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., female.... more FIGURES 12–16. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., female. 12. Genitalia, ventral view. 13. Tergite IX. 14. Dorsomesal lobe. 15. Ventrolateral lobe. 16. Apodeme lobe.
Bookmarks Related papers MentionsView impact
FIGURES 5–6. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., male. 5. ... more FIGURES 5–6. Polypedilum (Pentapedilum) tuburcinatum Andersen et Bello González sp. n., male. 5. Hypopygium, dorsal view. 6. Hypopygium with anal point and tergite IX removed, dorsal aspect to the left and ventral aspect to the right.
Bookmarks Related papers MentionsView impact
Uploads
Papers by Jan-robert Baars