Meio- and macrofauna communities in three sandy beaches of the northern Adriatic Sea protected by artificial reefs

Interactions between meio- and macrofaunal assemblages and food availability were investigated in relation to tourism pressures on three beaches of the northern Adriatic Sea. All beaches were characterised by the presence of artificial reefs, freshwater inputs and tourism pressures. Beach sediments displayed high organic loads and low protein and chlorophyll a contributions to the bulk of the organic matter. Consequently, the organic matter was of mostly refractory composition and, thus, of scarce nutritional quality. Macrofaunal community structure and biomass were related to the quantity and nutritional quality of sedimentary organic matter, whereas meiofauna was apparently not. No relationships were found between physical variables and the metazoan communities. Most likely, the presence of artificial reefs reduced the physical impact of waves on the beach assemblages, whereas the presence of synergistic human impacts, including freshwater inputs and the tourism pressure, negatively influenced both the meio- and the macrofaunal assemblages.     

Treatment of swine wastewater in aerobic granular reactors: comparison of different seed granules as factors

The granulation process, physic-chemical properties, pollution removal ability and bacterial communities of aerobic granules with different feed-wastewater (synthetic wastewater, R1; swine wastewater, R2), and the change trend of some parameters of two types of granules in long-term operated reactors treating swine wastewater were investigated in this experiment. The result indicated that aerobic granulation with the synthetic wastewater had a faster rate compared with swine wastewater and that full granulation in R1 and R2 was reached on the 30th day and 39th day, respectively. However, although the feed wastewater also had an obvious effect on the biomass fraction and extracellular polymeric substances of the aerobic granules during the granulation process, these properties remained at a similar level after long-term operation. Moreover, a similar increasing trend could also be observed in terms of the nitrogen removal efficiencies of the aerobic granules in both reactors, and the average specific removal rates of the organics and ammonia nitrogen at the steady-state stage were 35.33 mg·g⁻¹ VSS and 51.46 mg·g⁻¹ VSS for R1, and 35.47 mg·g⁻¹ VSS and 51.72 mg·g⁻¹ VSS for R2, respectively. In addition, a shift in the bacterial diversity occurred in the granulation process, whereas bacterial communities in the aerobic granular reactor were not affected by the seed granules after long-term operation.     

Functional traits and the growth-mortality trade-off in tropical trees

A trade-off between growth and mortality rates characterizes tree species in closed canopy forests. This trade-off is maintained by inherent differences among species and spatial variation in light availability caused by canopy-opening disturbances. We evaluated conditions under which the trade-off is expressed and relationships with four key functional traits for 103 tree species from Barro Colorado Island, Panama. The trade-off is strongest for saplings for growth rates of the fastest growing individuals and mortality rates of the slowest growing individuals (r2 = 0.69), intermediate for saplings for average growth rates and overall mortality rates (r2 = 0.46), and much weaker for large trees (r2 < or = 0.10). This parallels likely levels of spatial variation in light availability, which is greatest for fast- vs. slow-growing saplings and least for large trees with foliage in the forest canopy. Inherent attributes of species contributing to the trade-off include abilities to disperse, acquire resources, grow rapidly, and tolerate shade and other stresses. There is growing interest in the possibility that functional traits might provide insight into such ecological differences and a growing consensus that seed mass (SM), leaf mass per area (LMA), wood density (WD), and maximum height (H(max)) are key traits among forest trees. Seed mass, LMA, WD, and H(max) are predicted to be small for light-demanding species with rapid growth and mortality and large for shade-tolerant species with slow growth and mortality. Six of these trait-demographic rate predictions were realized for saplings; however, with the exception of WD, the relationships were weak (r2 < 0.1 for three and r2 < 0.2 for five of the six remaining relationships). The four traits together explained 43-44% of interspecific variation in species positions on the growth-mortality trade-off; however, WD alone accounted for > 80% of the explained variation and, after WD was included, LMA and H(max) made insignificant contributions. Virtually the full range of values of SM, LMA, and H(max) occurred at all positions on the growth-mortality trade-off. Although WD provides a promising start, a successful trait-based ecology of tropical forest trees will require consideration of additional traits.     

Combined effect of fire and water scarcity on vegetation patterns in arid lands

In many arid zones around the word, the vegetation spontaneously forms regular patterns to optimize the use of the scarce water resources. The patterns act as early warning signal that fragile ecosystems may suddenly undergo irreversible shifts, thus, interpreting the structural shape of vegetation patterns is crucial to deciphering the ecosystem history and its expected further development. The sudden and irreversible shift of delicate ecosystems as a consequence of minor variation of the climatic forcing has been studied extensively in the past. The attitude of the ecosystem to recover after a catastrophic event, such as fire, did not receive as much attention so far. Here we modelled fire, as a sudden shift of the ecosystem state variables and functionality and evaluated post-fire scenarios under the hypothesis that two major feedbacks shaped the vegetation patterns: a positive feedback between preferential infiltration and plant growth, and a second feedback between infiltration and vegetation burning. A simple model solving a set of partial differential equations for soil moisture, plant biomass, surface water and dead biomass balance predicted significantly diverse post-fire vegetation patterns depending on the fire severity and on the degree of soil water repellency induced by the vegetation burning.     

Ecotoxicological evaluation of fungicides used in viticulture in non-target organisms

Environmental Science and Pollution Research - The effect of fungicides, commonly used in vine cultures, on the health of terrestrial and aquatic ecosystems has been poorly studied. The objective...     

Crossing technology and sustainability in cities’ development

This paper deals with sustainability in cities and the role technology plays in furthering sustainable results. Recently, many interventions have been implemented in cities to propose paths and models promoting the sustainability of cities from an overall perspective. Technologies are favouring the achievement of aims recalling the three spheres of sustainability as proposed by Arcadis (2017), namely “planet”, “profit”, and “people”. The ties between technology and the three spheres are investigated through a content analysis of reports issued by the 10 cities with the most significant advances in terms of becoming sustainable cities, as indicated in the Arcadis Report 2016. The results highlight technology as an element crossing sustainability, as processes and models in cities management and service provisions to citizens are significantly changing. New tools are innovating the processes addressing environmental issues, thus leading to cost efficiency and better economic conditions. Parallel to this, new models for city management and the provision of public services are addressing the need for a better quality of life for citizens and cities’ other stakeholders. Technology itself is thought of as sustainable because it should lead to efficiency and being efficient itself. A qualitative cluster analysis and a focus on excerpts from reports are proposed to highlight the ties between technologies and the elements representing key issues in managing and leading a city towards more sustainable conditions.     

Reduced riparian zone width compromises aquatic macroinvertebrate communities in streams of southern Brazil

Recent changes in Brazilian legislation reduced the width of riparian forest buffer needed to be preserved in private properties from 30 to 15 m or less. The consequences of these modifications can be dramatic, mainly because riparian buffer width is an important parameter for riparian forest structure and functioning. Our study assessed whether (1) macroinvertebrate family richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) family richness decrease with reduced riparian buffer width; (2) taxonomic composition and functional feeding group (FFG) composition of macroinvertebrates vary with a reduced riparian buffer width; and (3) reduced riparian buffer width similarly influence the macroinvertebrate community in different stream substrates. We selected three fragments with different riparian buffer widths (>40, <30, and <15 m) in three streams (fourth and fifth orders) in the Sinos River watershed, southern Brazil. Our results show that on all substrate types, reducing the width of the riparian buffer altered neither the macroinvertebrate richness nor EPT richness. However, EPT richness was greater in the substrates stone and gravel than leaf litter, independent of riparian buffer width. There was a significant difference in macroinvertebrate composition among riparian buffer widths. The macroinvertebrate composition and FFG differed among substrates, independent of riparian buffer width. This study showed that riparian buffer widths <15 m altered the macroinvertebrate community. A width greater than 15 m is necessary to maintain the composition and trophic conditions of macroinvertebrate families similar to those found in reference states of conservation.     

Influence of the insecticides acetamiprid and carbofuran on arylamidase and myrosinase activities in the tropical black and red clay soils

The objective of this study was to determine the effects of two insecticides, namely, acetamiprid and carbofuran on the enzymatic activities of arylamidase (as glucose formed from sinigrin) and myrosinase (as β-naphthylamine formed from l-leucine β-naphthylamide) in the black and red clay soils collected from a fallow groundnut (Arachis hypogaea L.) fields in the Anantapur District, Andhra Pradesh, India. The study was realized within the framework of the laboratory experiments in which the acetamiprid and carbofuran were applied to the soils at different doses (1.0, 2.5, 5.0, 7.5, 10.0 kg ha^?1). Initially, the physicochechemical properties of the soil samples were analyzed. After 10 days of pesticide application, the soil samples were analyzed for the enzyme activities. Acetamiprid and carbofuran stimulated the arylamidase and myrosinase activities at lower concentrations after 10 days incubation. Striking stimulation in soil enzyme activities was noticed at 2.5 kg ha^?1, persists for 20 days in both the soils. Overall, higher concentrations (5.0–10.0 kg ha^?1) of acetamiprid and carbofuran were toxic or innocuous to the arylamidase and myrosinase activities. Nevertheless, the outcomes of the present study clearly indicate that the use of these insecticides (at field application rates) in the groundnut fields (black and red clay soils) stimulated the enzyme (arylamidase and myrosinase) activities.     

Exploring the use of computer models in participatory integrated assessment – experiences and recommendations for further steps

Integrated assessment (IA) can be defined as a structured process of dealing with complex issues, using knowledge from various scientific disciplines and/or stakeholders, such that integrated insights are made available to decision makers (J. Rotmans, Enviromental Modelling and Assessment 3 (1998) 155). There is a growing recognition that the participation of stakeholders is a vital element of IA. However, only little is known about methodological requirements for such participatory IA and possible insights to be gained from these approaches. This paper summarizes some of the experiences gathered in the ULYSSES project, which aims at developing procedures that are able to bridge the gap between environmental science and democratic policy making for the issue of climate change. The discussion is based on a total of 52 IA focus groups with citizens, run in six European and one US city. In these groups, different computer models were used, ranging from complex and dynamic global models to simple accounting tools. The analysis in this paper focuses on the role of the computer models. The findings suggest that the computer models were successful at conveying to participants the temporal and spatial scale of climate change, the complexity of the system and the uncertainties in our understanding of it. However, most participants felt that the computer models were less instrumental for the exploration of policy options. Furthermore, both research teams and participants agreed that despite considerable efforts, most models were not sufficiently user-friendly and transparent for being accessed in an IA focus group. With that background, some methodological conclusions are drawn about the inclusion of the computer models in the deliberation process. Furthermore, some suggestions are made about how given models should be adapted and new ones developed in order to be helpful for participatory IA. This revised version was published online in July 2006 with corrections to the Cover Date.     

Potential risks of natural mercury levels to wild predator fish in an Amazon reservoir

Mercury (Hg) is a toxic metal that bioaccumulates in aquatic organisms and along food chain. Many studies have reported the problem of mercury exposure in aquatic systems from Amazon basin, but very few have focused on the potential risks to wild fish. The present study reports the bioaccumulation of mercury and alterations in target organs of the predator fish Hoplias malabaricus (traíra) from Samuel reservoir, Amazon basin, Northern Brazil. About 18% of fish had mercury levels in muscle exceeding the safe limit for ingestion through food, established by WHO (0.5 μg Hg g(-1)). Fish were separated in two groups according to mercury bioaccumulation in liver (<0.2 μg Hg g(-1)-group I and >0.2 μg Hg g(-1)-group II) for biomarker comparisons. Catalase activity and number of macrophage centers were statistically higher in group II, confirming the potential of Hg to interfere with redox balance and to recruit defense cells to the liver. Conversely, erythrocyte nuclear alterations were less frequent in group II, indicating a more rigorous selection of erythrocytes or hormesis pattern of response. Glutathione S-transferase activity, lipid peroxidation, and histopathological analyses were not statistically different in the liver and gills of both groups. Comparison of lipid peroxidation levels of these fish with others captured in Southern Brazil during another study and the high incidence of morphological alterations in the liver and gills suggest that the bioaccumulation of mercury during continuous exposure is posing potential risks to the species.