Search results for "Communities"

Ecological network analysis reveals the inter-connection between soil biodiversity and ecosystem function as affected by land use across Europe

2016

Soil organisms are considered drivers of soil ecosystem services (primary productivity, nutrient cycling, carbon cycling, water regulation) associated with sustainable agricultural production. Soil biodiversity was highlighted in the soil thematic strategy as a key component of soil quality. The lack of quantitative standardised data at a large scale has resulted in poor understanding of how soil biodiversity could be incorporated into legislation for the protection of soil quality. In 2011, the EcoFINDERS (FP7) project sampled 76 sites across 11 European countries, covering five biogeographical zones (Alpine, Atlantic, Boreal, Continental and Mediterranean) and three land-uses (arable, gra…

Fungal community assemblage of different soil compartments in mangrove ecosystem

2017

AbstractThe fungal communities of different soil compartments in mangrove ecosystem are poorly studied. We sequenced the internal transcribed spacer (ITS) regions to characterize the fungal communities in Avicennia marina root-associated soils (rhizosphere and pneumatophore) and bulk soil compartments. The rhizosphere but not pneumatophore soil compartment had significantly lower fungal species richness than bulk soil. However, bulk soil fungal diversity (Shannon diversity index) was significantly higher than both pneumatophore and rhizosphere soil compartments. The different soil compartments significantly affected the fungal community composition. Pairwise sample analyses showed that bulk…

Do shifts in life strategies explain microbial community responses to increasing nitrogen in tundra soil?

2016

Subarctic tundra soils store large quantities of the global organic carbon (C) pool as the decomposition of plant litter and soil organic matter is limited by low temperatures and limiting nutrients. Mechanisms that drive organic matter decomposition are still poorly understood due to our limited knowledge of microbial communities and their responses to changing conditions. In subarctic tundra large grazers, in particular reindeer, exert a strong effect on vegetation and nutrient availability causing drastic nutrient pulses in the soils located along the migratory routes. Here we studied the effect of increased nitrogen (N) availability on microbial community structure and activities by lab…

Mercury, lead and cadmium concentrations in Talpa occidentalis and in their digeneans of the genus Ityogonimus

2019

Many parasites living in aquatic ecosystems are useful indicators of environmental health. On the other hand, information is scarcer with respect to the use of helminth parasites of vertebrates living in terrestrial ecosystems as monitoring tools for toxic element environmental pollution. The present study evaluates the suitability of the model Talpa occidentalis/Ityogonimus spp. as a bioindicator system for mercury (Hg), lead (Pb) and cadmium (Cd) contamination in agricultural soils from Asturias (Spain). Kidney and liver samples collected from T. occidentalis specimens (n = 36) and Ityogonimus spp. samples collected from 14 infected hosts were analyzed by ICP-MS. The highest mean levels o…

Peace Mediations: Recourse to the Arbitration in the kingdom of Valencia (XIV-XV Centuries)

2017

Arbitration, as a means of conciliation, had an extraordinary diffusion in the Medieval West. It had the advantage of being more quick and, generally, less expensive that the causes resolved by the ordinary courts. Moreover, it tried to reconcile the interests of the warring parties. This paper seeks to define the main features of the arbitration in the kingdom of Valencia during the Middle Ages focusing the observation on the small rural community of Vilafranca.

Zemes un vides zinātnes: Bioģeogrāfija

2003

Abundance of narG , nirS , nirK , and nosZ Genes of Denitrifying Bacteria during Primary Successions of a Glacier Foreland

2006

ABSTRACT Quantitative PCR of denitrification genes encoding the nitrate, nitrite, and nitrous oxide reductases was used to study denitrifiers across a glacier foreland. Environmental samples collected at different distances from a receding glacier contained amounts of 16S rRNA target molecules ranging from 4.9 × 10 5 to 8.9 × 10 5 copies per nanogram of DNA but smaller amounts of narG , nirK , and nosZ target molecules. Thus, numbers of narG , nirK , nirS , and nosZ copies per nanogram of DNA ranged from 2.1 × 10 3 to 2.6 × 10 4 , 7.4 × 10 2 to 1.4 × 10 3 , 2.5 × 10 2 to 6.4 × 10 3 , and 1.2 × 10 3 to 5.5 × 10 3 , respectively. The densities of 16S rRNA genes per gram of soil increased with…

Weed communities of rice fields in the central Pamir Alai Mountains (Tajikistan, Middle Asia)

2013

The study present results of geobotanical investigations conducted in rice fields in the central Pamir Alai Mts (Tajikistan, Middle Asia), mainly within Syr-Daria, Pyandzh, Zeravshan, Kafirnigan, Khanaka and Surkhandaria river valleys in the years 2009–2011. The researches were focused on classification of plant communities developing within this poorly investigated area. Habitat conditions were checked including conductometry, pH reaction, temperature, depth of water and, for several plots, also soil structure. Altogether 114 phytosociological relevés using the Braun-Blanquet method were sampled. The analyses classified the vegetation into 28 communities including 24 associations. Five new…

Developing Algebraic Thinking in a Community of Inquiry : Collaboration between Three Teachers and a Didactician

2009

In this thesis I report from a study of the development of algebraic thinking of three teachers, from lower secondary school, and a didactician from a university in Norway (myself). The thesis offers an account of the relationship between the participants’ development of algebraic thinking and the processes related to the creation and development of a community of inquiry. In addition, the thesis presents elements of the relationship between the teachers’ development of algebraic thinking and their thinking in relation to their teaching practice. My theoretical framework was elaborated according to the criteria of relevance and coherence. In order to conceptualise the participants’ developm…

Comparing the effects of introduced signal crayfish and native noble crayfish on the littoral invertebrate assemblages of boreal lakes

2015

The introduced North American signal crayfish Pacifastacus leniusculus (Dana) has replaced the native noble crayfish (Astacus astacus) in many European freshwaters and can be considered a new component of these ecosystems. The 2 species are apparently similar in many respects, but their ecological equivalence is uncertain and has been little investigated, especially at the whole-lake scale. We compared the effects of the 2 species on the abundance, species richness, and composition of littoral macroinvertebrate assemblages in a set of small- and mediumsized boreal lakes, which included 8 lakes with noble crayfish, 8 lakes with signal crayfish, and 8 lakes without crayfish. We collected semi…