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Another survey of Odonata on the Indonesian island of Belitung is reported. This survey was the second survey conducted in the Belitung area with International Dragonfly Fund support and was focused to Belitung Regency's outer islands. Seventy two species were recorded during the survey. Significant records from the surveyed islands include Amphicnemis kuiperi, Mortonagrion arthuri, Mortonagrion appendiculatum, Teinobasis ruficollis, Platylestes heterostylus, Pornothemis serrata, Pornothemis starrei and Tramea phaeoneura. Almost all the records are new to the small islands surveyed, except for Mendanau Island for which there were already records of four species. A checklist of the odonate fauna of the outer islands is given in an appendix.
The present checklist covers the fauna of the Trichopteran family Rhyacophilidae Stephens, 1836. Based on extensive surveys done during 2003–2019 and previous species records, we find that the family Rhyacophilidae is represented by two genera and 184 species in India. The genus Rhyacophila Pictet contains 165 species in India while the genus Himalopsyche Banks contains 19 described species. The Indian Himalayan region is inhabited by more species than the rest of India.
Die Iris-Wiesen sind im Untersuchungsgebiet typische Streuwiesen. Das Iridetum sibiricae bevorzugt nährstoffärmere, basenreiche, hydromorphe Böden im Karbonat- oder Silikat-Pufferbereich. Die Oberböden weisen meist einen relativ hohen Humusgehalt und ein relativ weites C/N-Verhältnis auf. Sie sind oft mit Ca oder Mg übersättigt, und sie haben in der Regel einen niedrigen Gehalt an laktat- und wasserlöslichem Phosphor. Die Subassoziation von Crepispaludosa besiedelt vorwiegend mäßig nasse Niedermoore, Anmoore und Augleye. Die Typische Subassoziation kommt in erster Linie auf feuchten Augleyen vor. Die Subassoziation von Galium verum bevorzugt mäßig feuchte vergleyte Graue Auböden. Bei regelmäßiger Düngung und Zweischnittnutzung wird das Iridetum sibiricae von der Cirsium oleraceum-Persicaria bistorta-Gesellschaft ersetzt. Auf regelmäßig überfluteten, nassen Standorten wird das Iridetum sibiricae insbesondere vom Caricetum gracilis abgelöst. Auf tiefgründig versauerten Niedermooren erfolgt ein Ersatz durch das Junco-Molinietum caeruleae. Bei Iris sibirica bewirken die frühe Cutinisierung der Rhizodermis, die besonders starke Verholzung der Exodermis und die Gerbstoffeinlagerung in die Rindenzellen einen ausgeprägten Fäulnisschutz. Durch Auflösung des Rindengewebes wird der Gasaustausch auf den hydromorphen Böden verbessert. Die Wurzeln von Iris sibirica sind mit VAM infiziert; dadurch dürfte die P-Aufnahme aus den P-armen Böden verbessert werden. Das Streugut der Iris-Wiesen kann nur als Stalleinstreu verwendet werden; es hat de facto keinen Futterwert für Milchkühe. Es zeichnet sich in erster Linie durch einen relativ hohen Rohfasergehalt und durch einen ziemlich niedrigen Rohproteingehalt aus; auch die Verdaulichkeit der organischen Masse und die Netto-Energielaktation sind sehr niedrig. Das Kräuter-reiche Streugut weist einen niedrigen Gehalt an N, P, K und Na auf; die Gehalte an Ca, Mg, Fe, Mn, Zn, Co, Cr, Ni, Cd, Pb und As sind zum Teil sehr hoch. Der hydromorphe Boden und der Kräuter-reiche Pflanzenbestand sind hauptverantwortlich für die relativ hohen Schwermetall- und As-Gehalte im Streugut der Iris-Wiesen. Die relativ artenreichen Iris-Wiesen sind Lebensraum für viele seltene und geschützte Pflanzen- und Tierarten. Die Pflege und Erhaltung der Iris-Wiesen ist eine wichtige Aufgabe der Landwirtschaft; sie wird nur durch eine traditionelle Streuwiesennutzung gewährleistet.
Patterns and processes of cladogenesis among taxa living on the Mozambique ‘sky islands’ remain poorly studied. During the present study, we report on a new freshwater crab species from Mount Lico, an inselberg and ‘sky island’ in the Zambezia Province of Mozambique. Phylogenetic analyses using three mitochondrial DNA sequence loci (12S rRNA, 16S rRNA and COI) were used to determine the evolutionary placement of the freshwater crab specimens from Mount Lico. The freshwater crab specimens from Mount Lico were retrieved sister to Potamonautes choloensis. The new species, Potamonautes licoensis sp. nov., is described and compared with other southern African freshwater crab species. Divergence time estimations for the Mozambican freshwater crab species suggest a Miocene / Plio–Pleistocene diversifi cation. Some endemic ‘sky island’ species form an early branching and are sister to other predominantly East African species, while other ‘sky island’ species are more recently derived and nested within a predominantly southern African clade. The present study presents the description of the fourth endemic freshwater crab species from Mozambique and suggests that the species diversity in the country is likely highly underrepresented, reiterating the call for renewed systematic surveys. An argument for the conservation of these mountainous ‘sky islands’ is presented.
Four new species of Brueelia Kéler, 1936 are described and illustrated. All of them parasitize African endemic host species in the families Passeridae, Ploceidae, and Estrildidae (Passeriformes). They are: Brueelia pofadderensis sp. nov. ex Passer melanurus damarensis Reichenow, 1902 and P. m. vicinus Clancey, 1958; B. semiscalaris sp. nov. ex Granatina granatina (Linnaeus, 1758); B. sima sp. nov. ex Malimbus nitens (Gray, 1831); B. terpsichore sp. nov. ex Euplectes jacksoni (Sharpe, 1891) and E. progne delamerei (Shelley, 1903). In addition, Brueelia bicurvata (Piaget, 1880) is redescribed and reillustrated from non-type material. A summary of all published records of lice in the Brueelia complex from Africa since 1980 is provided. We also estimate the unknown diversity of African species of Brueelia based on an index of host specificity calculated for each host family independently. The unknown diversity is estimated to be over 1000 species of Brueelia from African hosts, compared to the < 50 species in this genus currently recorded from Africa.
The current forest policy in Germany is to change forest monocultures into mixed forests. This is based on the assumption that monocultures are less robust against climatic influences (e.g. storm, drought), more susceptible to pest organisms (JACTEL et al. 2002, WOODS 2003, BURTON et al. 1992) and are for several insect taxa known to show a lower species richness in comparison to mixed forests (YOUNG 1986, BARKMAN 1992, BURKHART & THAM 1992, DENNIS 1997, BRAGANCA et al. 1998). This investigation wanted to verify this thesis in forests consisting of European beech (Fagus sylvatica), Norway spruce (Picea abies) and of both tree species. The area of investigation was in the Solling region, a large woodland in Lower Saxony (Germany).
Es wird über vierjährige Untersuchungen auf zwei Parzellenversuchen sowie Praxisschlägen in Bayern berichtet, bei denen im Vergleich zum intensiven Ackerbau die Auswirkungen von Extensivierungsprogrammen (Rotationsgrünbrache, Ökologischer Landbau, Bayerisches Kulturlandschaftsprogramm) und ihren Varianten auf die Segetalvegetation verfolgt wurden. Die Programme tragen in unterschiedlichem Maße zur Erhaltung einer standortgemäßen Segetalarten-Grundgarnitur bei. Besonders der Ökologische Landbau und die Rotationsgrünbrache mit Selbstbegrünung wirken sich positiv auf die Wildflora der Äcker aus. Generell ist für die Erhaltung von Segetalarten
- Extensivierung besser als Stillegung,
- Rotationsbrache besser als Dauerbrache,
- Selbstbegrünung besser als Ansaat.
The current knowledge of the scorpionfly genus Dicerapanorpa Zhong & Hua, 2013 is taxonomically reviewed. Two new species of Dicerapanorpa are described and illustrated, increasing the species number of this genus to 20. Dicerapanorpa bifurcata sp. nov. from the Minshan Mountains, Sichuan Province, is characterized by the absence of the paramere basal branch and the elongated mesal branch in males, and the medigynium having a short basal stalk in females. Dicerapanorpa zhengkuni sp. nov. from the Wuling and Miaoling Mountains, Guizhou Province, is distinguishable by the greatly elongated hypovalves, the very short basal branch of the paramere, and the dorsomedially curved lateral branch in males, and the rounded main plate of the medigynium in females. An updated key to species of Dicerapanorpa is presented.
High grazing pressure from over-abundant macropods (kangaroos) is perceived to have a detrimental impact on biodiversity. Studies have shown potential changes in state and retardation of degraded vegetation recovery while other investigations have shown correlations with increased floristic diversity. The responses of grasslands to high impact macropod grazing may not be universal. Endangered Themeda triandra-dominated grasslands, on coastal headlands of New South Wales (NSW) and the associated threatened flora are thought to be negatively affected by high macropod grazing. We assess these assumptions via a comparative investigation across 46 headlands (467 plots) on the North Coast of NSW, and a BACI (Before and After Control Incident) design grazing exclusion experiment at a particularly significant site. We compare floristic richness, species density, evenness, Shannon H, Whittaker Beta Diversity, occurrence of listed threatened flora, average sward height and macropod density. Look At Me Now Headland (LAMN), between Coffs Harbour and Woolgoolga has one of the highest recorded population densities of macropods. Here 16 permanent plots were placed with grazing exclusion cages erected around half. Sampling occurred annually (October-November) for four consecutive years (2015-2018). Under high macropod grazing pressure LAMN Headland was found to have the highest scores for total richness, species density, species diversity and moderate to high values for species evenness and beta diversity. Within grazing exclusion plots the sward height increased significantly and was associated with a significant decrease in species density, beta and alpha diversity. Our results indicate that macropod grazing, even at the highest intensities, may be beneficial to floristic species diversity within the endangered Themeda-grasslands of coastal headlands and seacliffs within the North Coast Bioregion of NSW; our broader comparative study would suggest that this may also be the case on other headlands.
The intensification of agricultural practices has led to a severe decrease in grassland biodiversity. Although there is strong evidence that organic farming can reduce the negative impacts of land use, knowledge regarding the most beneficial management system for species richness on organic grasslands is still scarce. This study examines differences in the biodiversity of plants and butterflies on rotationally and continuously grazed pastures as well as on meadows cut twice per year on two large organic suckler cow farms in NE Germany. Vegetation and flower abundance, as factors likely to influence butterfly abundance and diversity, were compared and used to explain the differences. The data attained by vegetation assessments and monthly transect inspections from May to August were analyzed using descriptive statistics and nonparametric methods. The abiotic site conditions of the studied plots had more influence on plant species numbers than the management method. Dry and nutrient-poor areas (mainly poor types of Cynosurion) and undrained wet fens (Calthion) were important for phytodiversity, measured by the absolute number of species, indicator species for ecologically valuable grasslands and the Shannon Index. Meadows tended to have more indicator species than pastures, where small-scale special sites such as wet depressions were crucial for plant diversity. Butterfly diversity was very low, and 90% of the recorded butterflies were individuals of the generalist species Pieris napi. Butterfly abundance depended mainly on occurrence of specific habitat types and specific larval host plants. Supply of flowers was crucial only in certain time periods. Differences in butterfly abundance between the management systems could be explained by the site conditions of the studied grasslands. We conclude that meadows are more favorable to support ecologically valuable plant species; however, their extension is contradictory to the organic farming method of suckler cows maintained outside of stables. Rotationally grazed pastures could be a compromise that would enhance the temporal heterogeneity of flower abundance and vegetation structure. The plant diversity on pastures should be improved by less intensive grazing on special sites and plant species enrichment by means of hay transfer. For enhancing butterfly diversity we suggest to reduce land use intensity especially on poor soils. Considering the economic perspective of the farms, small parts of the agricultural area could be sufficient if connectivity to other suitable habitats is assured. Flower abundance and diversity of larval host plants could be promoted by high diversity of farming practices as well as pre-serving small uncut strips of meadows.