The relative importance of COVID-19 pandemic impacts on biodiversity conservation globally

The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future.     

Production of hydrogen and value-added carbon materials by catalytic methane decomposition: a review

Environmental Chemistry Letters - Dihydrogen (H2), commonly named “hydrogen”, is attracting research interest due to potential applications in fuel cells, vehicles, pharmaceuticals and...     

Carbon dioxide methanation on heterogeneous catalysts: a review

Environmental Chemistry Letters - The Ukraine war has strongly accentuated the ongoing energy and environmental issues, thus requiring a fast development of alternative and more local fuels. For...     

A practical application of Driscoll's equation for predicting the acid-neutralizing capacity in acidic natural waters equilibria with the mineral phase gibbsite

A practical application of Driscoll's equation for predicting the acid-neutralizing capacity (ANC) in acidic waters equilibria with the mineral phase gibbsite is reported in this paper. Theoretical predication values of ANC are compared with the experimental data obtained from different literatures. The effect of aluminum (Al) on the value of ANC is investigated. It indicates that Al plays an important role in regulating the buffering effects in acidic natural waters. Failure to consider Al in acidic waters may bias assessment results in certain situations so as to overestimate the ANC values in response to increase in atmospheric deposition.     

Dynamics of aluminum speciation in forest-well drainage waters from the Rhode River watershed, Maryland

This paper reports an investigation of the dynamics of aluminum (Al) speciation in the forest-well waters from study site 110 of the Rhode River watershed, a representative sub-unit of Chesapeake Bay. Seasonal changes of Al speciation are evaluated by a modified MINEQL computer model using chemical equilibrium calculation. It was found that Al-F and Al-Org complexes were the dominate forms, whereas toxic forms of Al3+ and Al-OH were not significant. This indicates that Al toxicity is not very serious in the Rhode River area due to the high concentrations of fluoride and organic materials, even though sometimes pH is very low (approximately 4). Increased H+ or some other associated factors may be responsible for the decline in fish and amphibian population on the watershed.     

Observation and simulation of net primary productivity in Qilian Mountain, western China

We modeled net primary productivity (NPP) at high spatial resolution using an advanced spaceborne thermal emission and reflection radiometer (ASTER) image of a Qilian Mountain study area using the boreal ecosystem productivity simulator (BEPS). Two key driving variables of the model, leaf area index (LAI) and land cover type, were derived from ASTER and moderate resolution imaging spectroradiometer (MODIS) data. Other spatially explicit inputs included daily meteorological data (radiation, precipitation, temperature, humidity), available soil water holding capacity (AWC), and forest biomass. NPP was estimated for coniferous forests and other land cover types in the study area. The result showed that NPP of coniferous forests in the study area was about 4.4 tCha(-1)y(-1). The correlation coefficient between the modeled NPP and ground measurements was 0.84, with a mean relative error of about 13.9%.     

Assessing the organic composition of urban surface films using nuclear magnetic resonance spectroscopy

Recently it has been shown that urban surfaces are covered with a thin film which mediates the fate, distribution and accumulation of semi-volatile organic compounds in the environment. In this study we apply a combination of solution, semi-solids, and solid state nuclear magnetic resonance (NMR) methods to provide a general overview of the organic constituents. In surface film collected from 30 m2 of outside windows over an area of 12 km2 in downtown Toronto, we roughly estimate that the organic carbon is approximately 35% carbohydrate, approximately 35% aliphatics, approximately 20% aromatics, and approximately 10% carbonyl groups. Various aliphatic groups can be identified including a number of acids, alcohols, alkanes, and alkenes. Also, numerous intact aliphatic esters are apparent that have not been observed before, as well as carbohydrates. The aromatic species include a small portion that appears to be derived from a polymer of styrene, in addition a larger fraction is consistent with polyhydroxylated PAH derived material, although this assignment is tentative and based solely on 1-D NMR data only. In addition, signals from polybutadiene are present and while accurate quantification is not possible, it appears that this polymer may be up to a few percents by weight of the total organic material.     

Evaluation of heavy metal contamination in Phaeozem of northeast China

Surface and profile Phaeozem soil samples from 31 locations affected by various anthropogenic activities such as mining, chemical manufacturing, traffic emission and pesticide application were collected in Heilongjiang Province and Jilin Province, northeast China. The range of total concentrations of four heavy metals Cd, Pb, Cu and Zn in the soil was 0.011–3.137, 10.31–62.34, 9.74–51.21 and 39.54–247.59 mg kg⁻¹, respectively, determined using the acidic digestion procedure. Four methods including single contamination evaluation, background concentration comparison, surface/subsurface concentration comparison and exchangeable fraction evaluation were used to evaluate the extent of metal contamination in Phaeozem. The results indicated that different activities increased the concentrations of the heavy metals in surface soils, where high concentrations of cadmium and lead were found close to chemical plants and in the suburbs of the investigated cities. The four methods showed a general trend of increased soil contamination with heavy metals. Cadmium was of the most concern compared with the other contaminated elements in the study area, due to the long-term phosphatic fertilizer utilization and industrial activities. The proper evaluation method for cadmium contamination was the background concentration comparison, while for zinc and copper was the single contaminative index evaluation. Cadmium and lead could be the potential environmental risk in the Phaeozem area based on the different evaluations.     

Energy maximization by selective feeding on tissues of the venerid clam <Emphasis Type="Italic">Marcia hiantina</Emphasis> in the marine scavenger <Emphasis Type="Italic">Nassarius festivus</Emphasis> (Gastropoda: Nassariidae)

Feeding selectivity of the intertidal scavenging gastropod Nassarius festivus on four types of tissue (soft tissue, adductor muscle, foot, mantle margin) of the venerid clam Marcia hiantina was studied by field observations and laboratory experiments. Both approaches showed similar results with the soft tissue and adductor muscle being much preferred. As the energy content of the four types of tissue was similar and individuals of N. festivus rearing in different types of tissue obtained similar growth rates both in shell length and in body wet weight, differential consumption was most likely determined by the palatability of the tissues. Energy intake in a meal for N. festivus was estimated at 10.92, 9.17, 3.86 and 2.02 cal meal⁻¹ ind⁻¹ for soft tissue, adductor muscle, mantle margin, and foot, respectively. In view of the small size and sporadic distribution of the carrion, and intense competition among the conspecifics, selective feeding on more palatable tissues maximizes energy intake for scavengers like N. festivus.     

Characterization of major chemical components of fine particulate matter in North Carolina

This paper presents measurements of daily sampling of fine particulate matter (PM2.5) and its major chemical components at three urban and one rural locations in North Carolina during 2002. At both urban and rural sites, the major insoluble component of PM2.5 is organic matter, and the major soluble components are sulfate (SO4(2-)), ammonium (NH4(+)), and nitrate (NO3(-)). NH4(+) is neutralized mainly by SO4(2-) rather than by NO3(-), except in winter when SO4(2-) concentration is relatively low, whereas NO3(-) concentration is high. The equivalent ratio of NH4(+) to the sum of SO4(2-) and NO3(-) is < 1, suggesting that SO4(2-) and NO3(-) are not completely neutralized by NH4(+). At both rural and urban sites, SO4(2-) concentration displays a maximum in summer and a minimum in winter, whereas NO3(-) displays an opposite seasonal trend. Mass ratio of NO3(-) to SO4(2-) is consistently < 1 at all sites, suggesting that stationary source emissions may play an important role in PM2.5 formation in those areas. Organic carbon and elemental carbon are well correlated at three urban sites although they are poorly correlated at the agriculture site. Other than the daily samples, hourly samples were measured at one urban site. PM2.5 mass concentrations display a peak in early morning, and a second peak in late afternoon. Back trajectory analysis shows that air masses with lower PM2.5 mass content mainly originate from the marine environment or from a continental environment but with a strong subsidence from the upper troposphere. Air masses with high PM2.5 mass concentrations are largely from continental sources. Our study of fine particulate matter and its chemical composition in North Carolina provides crucial information that may be used to determine the efficacy of the new National Ambient Air Quality Standard (NAAQS) for PM fine. Moreover, the gas-to-particle conversion processes provide improved prediction of long-range transport of pollutants and air quality.