The effect of diesel fuel sulfur content on particulate matter emissions for a nonroad diesel generator

The effect of sulfur content on diesel particulate matter (DPM) emissions was studied using a diesel generator (Generac Model SD080, rated at 80 kW) as the emission source to simulate nonroad diesel emissions. A load simulator was used to apply loads to the generator at 0, 25, 50, and 75 kW, respectively. Three diesel fuels containing 500, 2100, and 3700 ppm sulfur by weight were selected as generator fuels. The U.S. Environmental Protection Agency sampling Method 5 "Determination of Particulate Matter Emissions from Stationary Sources" together with Method 1A "Sample and Velocity Traverses for Stationary Sources with Small Stacks or Ducts" was adopted as a reference method for measurement of the exhaust gas flow rate and DPM mass concentration. The effects of various parameters on DPM concentration have been studied, such as fuel sulfur contents, engine loads, and fuel usage rates. The increase of average DPM concentrations from 3.9 mg/Nm3 (n cubic meter) at 0 kW to 36.8 mg/Nm3 at 75 kW is strongly correlated with the increase of applied loads and sulfur content in the diesel fuel, whereas the fuel consumption rates are only a function of applied loads. An empirical correlation for estimating DPM concentration is obtained when fuel sulfur content and engine loads are known for these types of generators: Y = Zm(alphaX + beta), where Y is the DPM concentration, mg/m3, Z is the fuel sulfur content, ppm(w) (limited to 500-3700 ppm(w)), X is the applied load, kW, m is the constant, 0.407, alpha and beta are the numerical coefficients, 0.0118 +/- 0.0028 (95% confidence interval) and 0.4535 +/- 0.1288 (95% confidence interval), respectively.     

Modeling mercury fluxes and concentrations in a Georgia watershed receiving atmospheric deposition load from direct and indirect sources

This paper presents a modeling analysis of airborne mercury (Hg) deposited on the Ochlockonee River watershed located in Georgia. Atmospheric deposition monitoring and source attribution data were used along with simulation models to calculate Hg buildup in the subwatershed soils, its subsequent runoff loading and delivery through the tributaries, and its ultimate fate in the mainstem river. The terrestrial model calculated annual watershed yields for total Hg ranging from 0.7 to 1.1 microg/m2. Results suggest that approximately two-thirds of the atmospherically deposited Hg to the watershed is returned to the atmosphere, 10% is delivered to the river, and the rest is retained in the watershed. A check of the aquatic model results against survey data showed a reasonable agreement. Comparing observed and simulated total and methylmercury concentrations gave root mean square error values of 0.26 and 0.10 ng/L, respectively, in the water column, and 5.9 and 1 ng/g, respectively, in the upper sediment layer. Sensitivity analysis results imply that mercury in the Ochlockonee River is dominated by watershed runoff inputs and not by direct atmospheric deposition, and that methylmercury concentrations in the river are determined mainly by net methylation rates in the watershed, presumably in wetted soils and in the wetlands feeding the river.     

A salamander’s toxic arsenal: review of skin poison diversity and function in true salamanders,genus <Emphasis Type="Italic">Salamandra</Emphasis>

Terrestrial salamanders of the genus Salamandra represent one of the most prominent groups of amphibians. They are mainly distributed across Europe but also reach Northern Africa and the Near East. Members of the six currently accepted species have long been known to be poisonous; however, work on their toxins was mostly published in German language, and therefore, many nuances of these studies have remained hidden from the majority of herpetologists and toxinologists. Several Salamandra species are called fire salamanders due to their highly contrasted, black-yellow colouration which probably serves to deter predators, although thorough evidence for aposematism in Salamandra is still lacking. Salamandra skin toxins do not only represent a potent antipredator defence but may also have antimicrobial effects. A better understanding of this dual function of Salamandra skin secretions is of utmost importance in the face of the emergence of a fungal disease causing catastrophic declines of fire salamanders in Central Europe, caused by the fungus Batrachochytrium salamandrivorans. In this review, we summarize the knowledge on Salamandra toxins, providing a list of the compounds so far isolated from their secretion and focusing on the bioactivity of the major compounds in Salamandra secretions, the steroidal alkaloids. We identify priorities for future research, including a screening of co-occurrence of steroidal alkaloids and tetrodotoxins in salamandrids, chemical characterization of already identified novel steroidal compounds, elucidation of the presence and role of peptides and proteins in the secretion, and experimental in vitro and in vivo study of the interactions between bioactive compounds in Salamandra skin secretions and cutaneous fungal and bacterial pathogens.     

Assessment of soil erosion under rainfed sugarcane in KwaZulu‐Natal,South Africa

Soil erosion from agricultural land use runoff is a major threat to the sustainability of soil composition and water resource integrity. Sugarcane is an important cash and food security crop in South Africa, subjected to an intensive soil erosion, and consequently, severe land degradation. This study aimed to investigate soil erosion and associated soil and cover factors under rainfed sugarcane, in a small catchment, KwaZulu‐Natal, South Africa. Three replicated runoff plots were installed at different slope positions (down, mid and upslope) within cultivated sugarcane fields to monitor soil erosion during the 2016–2017 rainy season. On average, annual runoff (RF) was significantly greater from 10 m² plots with 1163.77 ± 2.63 l/m/year compared to 1 m² plots. However, sediment concentration (SC) was significantly lower in 10 m² (0.34 ± 0.04 g/l) compared to 1 m² (6.94 ± 0.24 g/l) plots. The annual soil losses (SL) calculated from 12 rainfall events was 58.36 ± 0.77 and 8.84 ± 0.20 t/ha from 1 m² and 10 m² plots, respectively. The 1 m² plot, SL (2.4 ± 1.41 ton/ha/year) in the upslope experienced 33% more loss than the midslope and 50% more loss than the downslope position. SL was relatively lower from the 10 m² plots than the 1 m² plots, which is explained by high sediment deposition at the greater plot scale. SL was negatively correlated with the soil organic carbon stocks (r = ?0.82) and soil surface cover (r = ?0.55). RF decreased with the increase of slope gradient (r = ?0.88) and soil infiltration rate (r = ?0.87). There were considerable soil losses from cultivated sugarcane fields with low organic matter. These findings suggest that to mitigate soil erosion, soil organic carbon stocks and vegetation cover needs to be increased through appropriate land management practices, particularly in cultivated areas with steep gradients.     

Protective clothing for pesticide operators: part I – selection of a reference test chemical for penetration testing

A systematic approach was taken to develop a database for protective clothing for pesticide operators; results are reported as a two-part series. Part I describes the research studies that led to identification of a pesticide formulation that could serve as a reference test chemical for further testing. Measurement of pesticide penetration was conducted using different types of pesticide formulations. Six fabrics were tested using 10 formulations at different concentrations. Three formulations were subsequently selected for further testing. Analysis of the data indicated that, when compared with other formulations, mean percent penetration of 5% Prowl 3.3 EC [emulsifiable concentrate diluted to 5% active ingredient (pendimethalin)] is either similar to or higher than most test chemicals. Those results led to choosing 5% Prowl 3.3 EC as a reference test liquid. Part II of the study, published as a separate paper, includes data on a wide range of textile materials.     

Establishing a Regional Monitoring Strategy: The Pacific Northwest Forest Plan

adaptive monitoring design. Adaptive monitoring design is an iterative process that refines the specifications for monitoring over time as a result of experience in implementing a monitoring program, assessing results, and interacting with users. An adaptive design therefore facilitates ecosystem management. We also discuss lessons of temporal and spatial scales raised by the consideration of a design for ecosystem management. Three additional issues—integration of information from different sources, institutional infrastructure, and the roles of individuals working in an interagency setting—are also identified, but not developed in detail.     

A systematic review of animal personality in conservation science

Although animal personality research may have applied uses, this suggestion has yet to be evaluated by assessing empirical studies examining animal personality and conservation. To address this knowledge gap, we performed a systematic review of the peer-reviewed literature relating to conservation science and animal personality. Criteria for inclusion in our review included access to full text, primary research articles, and relevant animal conservation or personality focus (i.e., not human personality studies). Ninety-two articles met these criteria. We summarized the conservation contexts, testing procedures (including species and sample size), analytical approach, claimed personality traits (activity, aggression, boldness, exploration, and sociability), and each report's key findings and conservation-focused suggestions. Although providing evidence for repeatability in behavior is crucial for personality studies, repeatability quantification was implemented in only half of the reports. Nonetheless, each of the 5 personality traits were investigated to some extent in a range of conservations contexts. The most robust studies in the field showed variance in how personality relates to other ecologically important variables across species and contexts. Moreover, many studies were first attempts at using personality for conservation purposes in a given study system. Overall, it appears personality is not yet a fully realized tool for conservation. To apply personality research to conservation problems, we suggest researchers think about where individual differences in behavior may affect conservation outcomes in their system, assess where there are opportunities for repeated measures, and follow the most current methodological guides on quantifying personality.     

The adoption of a Climate Disaster Resilience Index in Chennai,India

Results derived from the Climate Disaster Resilience Index (CDRI)—consisting of five dimensions (economic, institutional, natural, physical, and social), 25 parameters, and 125 variables—reflect the abilities of people and institutions to respond to potential climate‐related disasters in Chennai, India. The findings of this assessment, applied in the 10 administrative zones of the city, reveal that communities living in the northern and older parts of Chennai have lower overall resilience as compared to the flourishing areas (vis‐à‐vis economic growth and population) along the urban fringes. The higher resilience of communities along the urban fringes suggests that urbanisation may not necessarily lead to a deterioration of basic urban services, such as electricity, housing, and water. This indication is confirmed by a strong statistical correlation between physical resilience and population growth in Chennai. The identification of the resilience of different urban areas of Chennai has the potential to support future planning decisions on the city's scheduled expansion.     

The Precautionary Principle and the Prevention of Marine Pollution

This paper argues that the environmental changes witnessed in the past decade call for a new approach to environmental management; an approach based not on the principle of the assimilative capacity of the environment but on the precautionary principle, and the emerging preventive environmental paradigm. Uncertainties in scientific knowledge and complexities in ecological systems have presented specific failures of the assimilative capacity methodology. It is argued that these failures are not circumstantial in nature, nor are they the result of misapplication of science by scientists. Rather, they represent inherent problems in the use of the assimilative capacity concept in environmental management. The emergence of the precautionary principle is discussed and a formulation of the principle is presented. In conjunction with the operational approach of clean production, we believe that this principle offers a sounder basis for the prevention of marine pollution in the next decade.