Search results for " Community"
showing 10 items of 1104 documents
Confronto tra la nematofauna delle monoculture di mais e quella dei sistemi erbacei
2023
Gli studi sugli effetti dell'agricoltura sulla biodiversità del suolo sono diventati molto importanti, al fine di proteggere la salute dell'ambiente e migliorare la qualità dell'agricoltura. Le comunità di nematodi hanno dimostrato di offrire un potente strumento ecologico per valutare gli effetti delle pratiche agricole sul suolo. La ricerca è stata condotta in una monocoltura di mais (della durata di 20 anni) e in un ecosistema erbaceo seminaturale, dominato da Festuca spp. e Trifolium spp.. Ciascun sistema è stato sottoposto a due diverse pratiche di gestione delle colture (input alto (H) e basso (L)). L'obiettivo era quindi quello di studiare gli effetti di due diversi ecosistemi e dive…
Chemical, biochemical and microbial diversity through a Pachic Humudept profile in a temperate upland grassland
2013
There is great interest in understanding the factors that drive soil microbial activity and community composition in upland grassland ecosystems. We investigated the role of vertical gradients of chemical properties and various soluble C and N pools on soil microbial community structure by using a combination of chemical and biochemical methods coupled with PCR-denaturing gradient gel electrophoresis (DGGE) community fingerprinting and phospholipid fatty acid (PLFA) profiling. Soil samples were collected at increasing depth from a temperate upland grassland. Soil organic matter-related pools (total organic C and total Kjeldahl N) and functionally related active pools (microbial biomass C an…
OVERVIEW OF SOME TECHNIQUES ON DETECTION AND CHARACTERIZATION OF ARBUSCULAR MYCORRHIZAL FUNGI (A CASE STUDY IN ITALY)
2019
Arbuscular mycorrhizal fungi are mutualistic symbionts widespread among both cultivated and wild plants. They have different beneficial roles including stimulating plant growth and tolerance to wide varieties of biotic as well as abiotic stresses. So,the exact and optimize methods for quantification and detection of these fungi in roots and soils are necessary.These techniques are based on fungal sporesmorphological characterization as well as molecular characterization of fungi in soil or root samples.The work was carried out at the Institute for Sustainable Plant Protection (IPSP) of the National Research Council of Italy (CNR) in Turin. For this purpose, the AM fungal root colonization p…
The ectomycorrhizal community of Abies nebrodensis: preliminary results
2016
Abies nebrodensis (Lojac.) Mattei is a Critically Endangered forest tree included in Appendix I of the Bern Convention and as a priority species in Annexes II and IV of the Habitats Directive [1]. In situ and ex situ conservation strategies [2] and, more recently, a LIFE Natura project [3] allowed a marked improvement of health conditions of trees and of seedlings renewal. A first attempt to characterize the ectomycorrhizas of A. nebrodensis was carried out by Venturella & Rambelli [4]. In the frame of the activities of the II National Workshop of Ectomycorrhyza (Palermo, 2015), this paper reports the preliminary investigation carried out on the ectomycorrhyzal community of A. nebrodensis i…
Temporal and spatial variation of the algal community in a southern Mediterranean shallow system
2010
The algal community of a shallow system located in Western Sicily (Mediterranean Sea) has been investigated over 1 year in eight ponds (fredde). The spatio-temporal variation in total algal coverage, species richness and coverage in relation to environmental variables has been analysed. The algal community was very species-poor. A total of 50 taxa, mainly detached algae, were identified. A dominance of filamentous and foliose taxa was observed. Significant spatio-temporal differences in total algal coverage, species richness and coverage between the ponds of group A and those of group B were found. The separation into groups A and B was made a priori on the basis of different levels of prox…
Altered epiphyte community and sea urchin diet in Posidonia oceanica meadows in the vicinity of volcanic CO2 vents
2017
Ocean acidification (OA) predicted for 2100 is expected to shift seagrass epiphyte communities towards the dominance of more tolerant non-calcifying taxa. However, little is known about the indirect effects of such changes on food provision to key seagrass consumers. We found that epiphyte communities of the seagrass Posidonia oceanica in two naturally acidified sites (i.e. north and south sides of a volcanic CO2 vent) and in a control site away from the vent at the Ischia Island (NW Mediterranean Sea) significantly differed in composition and abundance. Such differences involved a higher abundance of non-calcareous crustose brown algae and a decline of calcifying polychaetes in both acidif…
Limited potential for bird migration to disperse plants to cooler latitudes
2021
Climate change is forcing the redistribution of life on Earth at an unprecedented velocity1,2. Migratory birds are thought to help plants to track climate change through long-distance seed dispersal3,4. However, seeds may be consistently dispersed towards cooler or warmer latitudes depending on whether the fruiting period of a plant species coincides with northward or southward migrations. Here we assess the potential of plant communities to keep pace with climate change through long-distance seed dispersal by migratory birds. To do so, we combine phenological and migration information with data on 949 seed-dispersal interactions between 46 bird and 81 plant species from 13 woodland communi…
Effects of fish-farm biodeposition on periphyton assemblages on artificial substrates in the southern Tyrrhenian Sea (Gulf of Castellammare, Sicily)
2007
An algal assemblage growing on artificial substrata of fish-farm cages was investigated. Specifically, algal response to the effects of fish-farm facilities was studied, in order to identify a possible future descriptor of biodeposition impact. Some sites were positioned upstream of the farms (at least 750 m; ‘controls’) and other sites were positioned downstream of the farms (‘impacts’). All sites were situated in the Tyrrhenian Sea. Control and impact sites differed significantly with regard to the dissolved nutrient profile. The fouling community (samples were scraped from buoys) displayed a reduction gradient in diversity which increased with the effect of fish farms. A total of 51 taxa…
Nematode community response to fish-farm impact in the western Mediterranean.
2002
A previous investigation on fish-farm biodeposition effects on benthos, carried out in the Gaeta Gulf (northwestern Mediterranean Sea), revealed a strong impact on meiofaunal assemblages. This study implements these findings by examining in detail the nematode assemblage and its response to organic enrichment from the start of a fish farm activity to the conclusion of the fish rearing cycle. Density, community structure and individual size were utilised for univariate (genus, trophic diversity and abundance patterns) and multivariate analyses (MDS) in order to identify the best descriptors of impact and the response of the nematode assemblages. Nematodes displayed significantly reduced dens…
Ecological impacts of global warming and water abstraction on lakes and reservoirs due to changes in water level and related changes in salinity
2015
According to the Intergovernmental Panel on Climate Change report released in September 2014, unprecedented changes in temperature and precipitation patterns have been recorded globally in recent decades and further change is predicted to occur in the near future, mainly as the result of human activity. In particular, projections show that the Mediterranean climate zone will be markedly affected with significant implications for lake water levels and salinity. This may be exacerbated by increased demands for irrigation water. Based on long-term data from seven lakes and reservoirs covering a geographical gradient of 52 of latitudes and a literature review, we discuss how changes in water le…