Analysis of the environmental impact on a stream: is only tannery to blame?

The contribution of wastewater from a tannery industry to the pollution of a stream was investigated. The main parameters studied were biochemical oxygen demand, chemical oxygen demand, chromium, dissolved oxygen, fecal and total coliforms, nitrogen, oils and greases, pH, phosphorous, sulfides, suspended solids, turbidity, and volatile solids. Three sampling points were located: (1) at the discharge point of tannery wastewater, (2) 50 m upstream, and (3) 80 m downstream of discharge point. Also was investigated the pollution at the stream source.     

Seasonal evaluation of outdoor/indoor air quality in primary schools in Lisbon

The aim of this study was to evaluate the indoor (I) and outdoor (O) levels of NO?, speciated volatile organic compounds (VOCs) and carbonyls at fourteen primary schools in Lisbon (Portugal) during spring, autumn and winter. Three of these schools were also selected to be monitored for comfort parameters, such as temperature and relative humidity, carbon dioxide (CO?), carbon monoxide (CO), total VOCs, and both bacterial and fungal colony-forming units per cubic metre. The concentration of CO? and bioaerosols greatly exceeded the acceptable maximum values of 1800 mg m?3 and 500 CFU m?3, respectively, in all seasons. Most of the assessed VOCs and carbonyls occurred at I/O ratios above unity in all seasons, thus showing the importance of indoor sources and building conditions in indoor air quality. However, it has been observed that higher indoor VOC concentrations occurred more often in the colder months, while carbonyl concentrations were higher in the warm months. In general, the I/O NO? ratios ranged between 0.35 and 1, never exceeding the unity. Some actions are suggested to improve the indoor air quality in Lisbon primary schools.     

Incorporating stakeholders’ preferences into a multi-criteria framework for planning large-scale Nature-Based Solutions

Hydro-meteorological risks are a growing issue for societies, economies and environments around the world. An effective, sustainable response to such risks and their future uncertainty requires a paradigm shift in our research and practical efforts. In this respect, Nature-Based Solutions (NBSs) offer the potential to achieve a more effective and flexible response to hydro-meteorological risks while also enhancing human well-being and biodiversity. The present paper describes a new methodology that incorporates stakeholders’ preferences into a multi-criteria analysis framework, as part of a tool for selecting risk mitigation measures. The methodology has been applied to Tamnava river basin in Serbia and Nangang river basin in Taiwan within the EC-funded RECONECT project. The results highlight the importance of involving stakeholders in the early stages of projects in order to achieve successful implementation of NBSs. The methodology can assist decision-makers in formulating desirable benefits and co-benefits and can enable a systematic and transparent NBSs planning process.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01419-4) contains supplementary material, which is available to authorized users.     

Interference of iron as a coagulant on MIB removal by powdered activated carbon adsorption for low turbidity waters

Powered activated carbon (PAC) is widely used in water treatment plants to minimize odors in drinking water. This study investigated the removal of 2-methylisoborneol (MIB) by PAC adsorption, combined with coagulation using iron as a coagulant. The adsorption and coagulation process were studied through different case scenarios of jar tests. The analysis evaluated the effect of PAC dosing in the liquid phase immediately before or after the coagulant addition. Ferric sulphate was used as the coagulant with dosages from 10 to 30 mg/L, and PAC dosages varied from 10 to 40 mg/L. The highest MIB removal efficiency (about 70%) was achieved without the coagulant addition and with the highest PAC dosage (40 mg/L). Lower MIB removal efficiencies were observed in the presence of coagulant, showing a clear interference of the iron precipitate or coagulant in the adsorption process. The degree of interference of the coagulation process in the MIB removal was proportional to the ratio of ferric hydroxide mass to the PAC mass. For both cases of PAC dosing, upstream and downstream of the coagulant injection point, the MIB removal efficiency was similar. However, MIB removal efficiency was 15% lower when compared with experiments without the coagulant application. This interference in the MIB adsorption occurs potentially because the coagulant coats the surface of the carbon and interferes with the MIB coming in contact with the carbon’s surface and pores. This constraint requires an increase of the PAC dosage to provide the same efficiency observed without coagulation.     

AN Amazon Perspective on the Forest-Climate Connection: Opportunity for Climate Mitigation, Conservation and Development?

Amazonia contains more carbon (C) than a decade of global, human-induced CO₂ emissions (60–80 billion tons). This C is gradually being released to the atmosphere through deforestation. Projected increases in Amazon deforestation associated with investments in road paving and other types of infra-structure may increase these C emissions. An increase of 25–40% in Amazon deforestation due to projected road paving could counterbalance nearly half of the reductions in C emissions that would be achieved if the Kyoto Protocol were implemented. Forecasted emission increases could be curtailed if development strategies aimed at controlling frontier expansion and creating economic alternatives were implemented. Given ancillary benefits and relative low costs, reducing deforestation in Amazonia and other tropical areas could be an attractive option for climate mitigation. Projects that help contain deforestation and reduce frontier expansion can play an important role in climate change mitigation but currently are not allowed as an abatement strategy under the climate regime. Creating incentives for forest conservation and decreased deforestation can be a unique opportunity for both forest conservation and climate mitigation.     

Full scale treatment of ASR wastes in a modified rotary kiln

A plant, designed for the thermo-valorisation of tyres, was specifically modified in order to treat Automobile Shredder Residue (ASR). Results from two full-scale combustion experiments, carried out on large ASR feeding lots (thousands of tons) indicate the proposed technology as a potential route to help the fulfilling of impending 95% reuse and recovery target set by the End of life Vehicle (ELV) Directive (January 2015). The paper describes the main operational troubleshot occurred during the first experiment (emissions at the stack out of regulatory limits and problems of clogging on the conveyer belt) and the consequent upgrading solutions (pre-treatment, introduction of waste double low-flow screw feeder and a cyclone prior to the main fan, modification of rotatory kiln inlet) adopted to allow, during the second long-term experiment, a continuous basis operation of the plant in full compliance with the discharge limit to the atmosphere. Characterization of both ASR and combustion residues allowed to quantify a 18% of combustion residues as not dangerous waste while only the 2% as hazardous one. A pre-treatment for the reduction of fines in the ASR was recommended in order to achieve the required energy recovery efficiency.     

Water quality in Minho/Miño River (Portugal/Spain)

Minho River, also called Miño (in Spain), extends to about 300 km from Spain to Portugal. The source of the river lies in Spain and in the last 75 km, the river defines the border between Portugal and Spain. Under the scope of a cooperation project between North Portugal and Galicia region of Spain, titled: “Valorization of the natural resources of the Minho/Miño drainage basin”, seven water-sampling campaigns were carried out during the last 2 years in Minho River basin. Seven sampling sites were selected along the international stretch, and five were chosen in the main Portuguese and Spanish tributaries of Minho River. Water quality based on the physicochemical and microbial parameters was assessed. According to the Portuguese legislation for surface waters, the international section of Minho River presents a reasonably good water quality (BOD₅ <5 mg/L, TNK <2 mg/L, and total phosphorous <1 mg P/L). Valença and Louro were found to be the most polluted sampling sites and Louro the most polluted tributary (maximum values observed: TSS?=?26 mg/L, BOD₅?=?6.6 mg O₂/L, COD?=?20.8 mg O₂/L, total nitrogen?=?9.9 mg N/L; minimum value observed: OD?=?1.3 mg O₂/L). A one-dimensional stream water quality model QUAL2Kw was calibrated using data measured in field surveys along the international stretch of Minho River. QUAL2Kw was also used to predict the impact of flow conditions, discharges, and tributaries on the water quality of international stretch of Minho River, essential to establish proposals for management and planning of Minho River Basin.     

Soluble and insoluble fractions of heavy metals in wet and dry atmospheric depositions in Bologna,Italy

Atmospheric depositions were collected monthly using a modified wet and dry sampler (dry deposition was collected on a water surface) located in Bologna, a northern Italian urban area, to evaluate the impact of airborne heavy metals on the local pollution load. Wet deposition samples were filtered and heavy metal contents in soluble and insoluble fractions were determined. The same procedure was applied to the water samples which collected dry deposition. The entire procedure was tested using a certified reference material (CRM), which provided satisfying recovery results. The percentage of heavy metal soluble fraction in dry deposition was generally lower than in wet one; Cd, V, Cu and Zn showed a higher average solubility than Cr, Ni and Pb both in wet and dry deposition. Factor analysis, after a varimax rotation of principal components, suggested possible anthropogenic sources which explain different metal deposition patterns. This data analysis also allowed to distinguish different clusters formed by monthly fluxes of heavy metals.     

Enrichment of organic pollutants in the sea surface microlayer (SML) at Terra Nova Bay, Antarctica: influence of SML on superficial snow composition

Concentrations of dissolved and particle-associated n-alkanes, phthalates and polycyclic aromatic hydrocarbons (PAHs) were measured in sea surface microlayer (SML) and sub-surface water (SSL) samples collected in the coastal area of Terra Nova Bay, Antarctica, during the Austral spring 1998/1999. SML concentrations of the selected organic compounds were higher than SSL values and the enrichment factors were greater in the particulate phase than in the dissolved phase. During the same campaign, "fresh" snow samples, collected at different altitudes (from sea level up to 2670 m) near the coast on Mt Melbourne, immediately after a snowy event, were analysed in order to provide more information on air/sea exchange processes. The same classes of organic compounds found in sea water were also present in "fresh" snow samples. The surfactant fluorescent organic matter (SFOM), adsorbed on the microdrop aerosol surface, could be considered the main constituent of the enrichment and the carrier at higher altitudes of organic compounds. In fact, hydrocarbons (n-alkanes and PAHs), which are not surfactants like phthalates, could interact with SFOM and follow the same fate.     

Production and biomass accumulation of periphytic diatoms growing on glass slides during a 1-year cycle in a subtropical estuarine environment (Bay of Paranaguá, southern Brazil)

Production rates, chlorophyll concentrations and general composition of periphytic diatom communities growing on glass slides were studied in relation to environmental parameters during one seasonal cycle in the Bay of Paranaguá, southern Brazil. Slides were routinely submersed at 1, 2 and 3 m depth and recovered weekly for microscopic examinations, analyses of chlorophyll, cell counts and in situ photosynthetic incubations using the Winkler titration method. Water samples were also collected at surface and bottom layers for determinations of temperature, salinity, nutrients and chlorophyll in the water. The periphytic community was mainly formed by epipelic and epipsammic species, dominated by Navicula phyllepta, Cylindrotheca closterium, Navicula spp. and Amphora sp. Weekly chlorophyll a and cell accumulations on slides varied from <1–32 mg m⁻² and up to 31 × 10⁸cells m⁻², respectively. Photosynthetic rates varied from <1 to 35 mg oxygen mg chlorophyll a ⁻¹ h⁻¹, with higher values in summer. Daily production varied from 5 to 3,600 mg oxygen m⁻² day⁻¹ (<0.01–1.4 g carbon m⁻² day⁻¹). Multiple regression analysis revealed that vertical differences in light conditions and grazing pressure jointly affected the influence of temperature on the seasonal patterns of cell densities and chlorophyll concentrations according to depth. Received: 27 April 2000 / Accepted: 16 August 2000