Search results for "Biomas"

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…

Initial Fish-Farm Impact on Meiofaunal Assemblages in Coastal Sediments of the Western Mediterranean

1999

We studied the initial impact of organic loads due to the biodeposition of a new fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and meiofaunal assemblages were investigated from July 1997 to February 1998 on a monthly basis at two stations: the first was located under the fish farm, while the second was at about 1 km distance, and served as control. Variations in the biochemical composition of the sedimentary organic matter and meiofaunal community structure were also related to changes in reared fish biomass. The presence of the cage-induced rapid changes in the benthic compartment: the sediments reached rapidly (i.e., after only …

Could cattle ranching and soybean cultivation be sustainable? A systematic review and a meta-analysis for the Amazon

2021

Abstract: Tropical forests are being destroyed to make space for agricultural activities with the assumption that they are required to feed the growing global population. Consequently, more sustainable practices are needed to guarantee food security and environmental protection of highly threatened natural biodiversity hotspots like the Amazon rainforest. Cattle ranching and soybean cultivation are by far the greater drivers of land use change and deforestation in the Amazon region. We performed a systematic review of papers related to these two main drivers and a meta-analysis on the effects of sustainable practices on different ecosystem services. The results of the review highlight a lar…

The effect of seagrass loss on macrozoobenthos community in a Mediterranean semi-enclosed coastal system

2009

Particulate Organic Matter Composition in A Semi-Enclosed Marine System

2001

Spatial and temporal changes in the biochemical composition of particulate organic matter in a semi-enclosed marine system (Stagnone di Marsala, Mediterranean Sea) were studied, on a monthly basis, from January to December 1994, in order to assess nutritional value of suspended particles for benthic suspension feeders. According to previous findings, the study site displayed a strong oligotrophy. Chlorophyll-a accounted for a very low fraction of the total suspended matter pool (0.1%), whereas at least 75% of POC was of detrital/heterotrophic origin. POC: PON ratio values indicate that bacterioplankton biomass accounted for a significant fraction of the total POC pool, displaying values com…

Palladium clusters on BNNT as catalysts for biomass conversion

2015

The construction of a heterogeneous catalytic systems by a bottom-up approach is a fascinating strategy well assisted by molecular level characterizations. In this sense, DFT investigations can be used with predictive and descriptive purposes both for the treatment of the catalyst/support and for the substrate/catalyst characterization. This should be particularly useful for highly perspective but scarcely treated systems such as boron nitride based supports. Among these, boron nitride nanotubes (BNNT) have been demonstrated to have high chemical and thermal stability as well as great mechanical strength and high thermal conductivity.[1] Moreover, a high affinity toward hydrogen [2] as well…

Performance of a MBR pilot plant treating high strenght wastewater: analysis of biomass activity and fouling behaviour

2012

Nowadays, due to the increasing awareness about environmental impact of discharges, it is necessary to realize biological processes that allow complete treatment of wastewater, able to produce high quality effluents that could be used for recycling and reuse purpose. A possible solution to cope with this issue is represented by membrane bioreactors (MBRs), which are combined systems including a bioreactor and a filtration unit. However, in presence of high strenght domestic or industrial wastewater, a modification in biomass kinetics as well as in sludge characteristics may occur. This situation is of importance, since microbial community characteristics can play an important role in membra…

Biokinetic Behaviour of Autochthonous Halophilic Biomass at Different Salinity: Comparison Between Activated Sludge and Granular Sludge Systems

2017

The main goal of this study was the evaluation of the impact of increasing salinity on halophilic biomass in forms of flocculent and granular sludge for the treatment of hypersaline fish-canning wastewater, focusing on the metabolic behavior of autotrophic biomass. For this purpose, two sequencing batch reactors, one with aerobic granular sludge (GSBR) and the other with flocculent activated sludge (SBR) were monitored. In both reactors, a halophilic biomass was cultivated from a real saline wastewater collected from a fish-canning industry. The salt concentration was stepwise increased (2 gNaCl L-1) from 30 gNaCl L-1 to 50 gNaCl L-1. Therefore, ammonia and nitrite uptake rates for granular…

TREATMENT OF LANDFILL LEACHATE IN SBR SYSTEMS: ANALYSIS OF BIOMASS ACTIVITY BY MEANS OF RESPIROMETRIC TECHNIQUES

2013

In the last decades landfilling has been the main method of municipal solid waste (MSW) disposal in many countries. MSW landfills are usually considered as a large biological reactor where the MSWs undergo anaerobic digestion producing gas and liquid emissions. Aged, or mature leachate, which is produced by older landfills, can be very refractory; for this reason mature leachate is difficult to treat alone, but it can be co-treated with sewage or domestic wastewater. The aim of the study was to investigate the feasibility of co-treatment of landfill leachate and synthetic wastewater in different percentages, in terms of process performance and biomass activity, by means of respirometric tec…

Respirometry for the assessment of biomass activity in Membrane Bioreactors

2017

The aim of the study was to use respirometric techniques for the characterization of biomass biokinetic behaviour in several MBR pilot plants characterized by different configurations, different operational conditions and fed with wastewater of different features (domestic/industrial). Four different MBR pilot plants were investigated: i) a sequencing batch MBR (SB-MBR) subjected to a gradual salinity increase; ii) a pre-denitrification MBR system for the treatment of saline wastewater contaminated by hydrocarbons; iii) a University of Cape Town MBR system (UCT-MBR) for the treatment of domestic wastewater subjected to a carbon-to-nitrogen (C/N) ratio variation; iiii) a UCT-IFAS-MBR for the…