A harvest failure approach to assess the threat from an invasive species

We present the idea of using potential infringements on annual allowable harvest targets as an approach to estimate threats from invasive species to the forest products sector. The approach uses present-day harvest levels as a reference level to estimate when and where the impact of a nonnative forest pest could become economically damaging. We use a generic model that simulates spread and damage by nonnative invasive species, basic harvest and forest growth through time. The concept is illustrated with a case study of a new nonnative invasive pest, Sirex noctilio Fabricius on pine resources in eastern Canada. Impacts of invasion on wood supply, in particular, the point at which present-day harvest levels are not attainable, were identified for 77 non-overlapping geographical regions that delimit the primary wood supply areas around large mills and wood processing facilities in eastern Canada. The results identify the minimum area of a pest outbreak that could trigger harvest shortages (approximately 12.5–14 M ha of pine forests in Ontario and Quebec). Beyond this level, the amount of host resource available for harvesting in any given year declines rapidly. The failure to sustain broad-scale harvest targets may be an attractive and intuitive indicator for policy makers and regulators interested in developing control and “slow-the-spread” programs for non-native forest pests.     

Optimal Pollution Trading Without Pollution Reductions: A Note1

García, Jorge H., Matthew T. Heberling, and Hale W. Thurston, 2011. Optimal Pollution Trading Without Pollution Reductions: A Note. Journal of the American Water Resources Association (JAWRA) 47(1):52‐58. DOI: 10.1111/j.1752‐1688.2010.00476.x Abstract: Various kinds of water pollution occur in pulses (e.g., agricultural and urban runoff). Ecosystems, such as wetlands, can serve to regulate these pulses and smooth pollution distributions over time. This smoothing reduces total environmental damages when “instantaneous” damages are marginally increasing. This paper introduces a water quality trading model between a farm (a pulse‐pollution source) and a firm (a more steady pollution source) where the object of exchange is the “temporary” retention of runoff as opposed to total runoff reductions. The optimal trading ratio requires firm emissions to be offset by more than a proportional retention of the initial agricultural runoff pulse. The reason is twofold: (1) emissions are steady or constant over time and, in this sense, have relatively larger environmental impact; and (2) certain kinds of runoff management cause delayed environmental damages.     

Environmental management system vs green specifications: How do they complement each other in the construction industry?

Environmental Management System (EMS) has been one of the important tools for sustainable construction for around two decades. However, many issues concerning sustainable development have not been properly addressed, and there is a need for the introduction of green specifications to advance green performance in construction through contract management. This paper defines green specifications, identifies the reasons for adopting green specifications and highlights the environmental issues that may not be addressed by solely adopting EMS. It also presents the results of a recent survey of practitioners concerning their opinions towards green specifications and possible impacts arising from their adoption. From the results of the survey, a framework for developing green specifications is deemed valuable for the cities striving for sustainability. Interestingly, the level of acceptable changes brought about by green specifications as perceived by different industry stakeholders is found to be unrelated to whether they were from organizations implementing EMS or not.     

Priority screening of toxic chemicals and industry sectors in the U.S. toxics release inventory: a comparison of the life cycle impact-based and risk-based assessment tools developed by U.S. EPA

Life Cycle Impact Assessment (LCIA) and Risk Assessment (RA) employ different approaches to evaluate toxic impact potential for their own general applications. LCIA is often used to evaluate toxicity potentials for corporate environmental management and RA is often used to evaluate a risk score for environmental policy in government. This study evaluates the cancer, non-cancer, and ecotoxicity potentials and risk scores of chemicals and industry sectors in the United States on the basis of the LCIA- and RA-based tools developed by U.S. EPA, and compares the priority screening of toxic chemicals and industry sectors identified with each method to examine whether the LCIA- and RA-based results lead to the same prioritization schemes. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) is applied as an LCIA-based screening approach with a focus on air and water emissions, and the Risk-Screening Environmental Indicator (RSEI) is applied in equivalent fashion as an RA-based screening approach. The U.S. Toxic Release Inventory is used as the dataset for this analysis, because of its general applicability to a comprehensive list of chemical substances and industry sectors. Overall, the TRACI and RSEI results do not agree with each other in part due to the unavailability of characterization factors and toxic scores for select substances, but primarily because of their different evaluation approaches. Therefore, TRACI and RSEI should be used together both to support a more comprehensive and robust approach to screening of chemicals for environmental management and policy and to highlight substances that are found to be of concern from both perspectives.     

Phosphorus and nitrogen in runoff after phosphorus- or nitrogen-based manure applications

Application of beef cattle () manure based on nitrogen (N) requirements of crops has resulted in elevated concentrations of soil test phosphorus (P) in surface soils, and runoff from this cropland can contribute to eutrophication of surface waters. We conducted a 3-yr field study (2005-2007) on a Lethbridge loam soil cropped to dryland barley () in southern Alberta, Canada to evaluate the effect of annual and triennial P-based and annual N-based feedlot manure on P and N in runoff. The manure was spring applied and incorporated. There was one unamended control plot. A portable rainfall simulator was used to generate runoff in the spring of each year after recent manure incorporation, and the runoff was analyzed for total P, total dissolved P, total particulate P, dissolved reactive P, total N, total dissolved N, total particulate N, NO-N, and NH-N. Annual or triennial P-based application resulted in significantly ( ≤ 0.05) lower (by 50 to 94%) concentrations or loads of mainly dissolved P fractions in runoff for some years compared with annual N-based application, and this was related to lower rates of annual manure P applied. For example, mean dissolved reactive P concentrations in 2006 and 2007 were significantly lower for the annual P-based (0.12-0.20 mg L) than for the annual N-based application (0.24-0.48 mg L), and mean values were significantly lower for the triennial P-based (0.06-0.13 mg L) than for the annual N-based application. In contrast, other P fractions in runoff were unaffected by annual P-based application. Our findings suggested no environmental benefit of annual P-based application over triennial P-based application with respect to P and N in runoff. Similar concentrations and loads of N fractions in runoff for the P- and N-based applications indicated that shifting to a P-based application would not significantly influence N in runoff.     

Effect of surface incorporation of broiler litter applied to no-till cotton on runoff quality

Surface application of broiler litter to no-till cotton could lead to degradation of water quality. Incorporation of broiler litter into the top surface soil (0.05 m) could alleviate this risk. A 2-yr field study was conducted on a silt loam upland soil to determine the effect of incorporation of broiler litter into the soil surface on nutrient and bacterial transport in runoff. The experimental design was a randomized complete block with four treatments and three replications. Treatments were (i) unfertilized control; (ii) surface-appliedbroiler litter at 7.8 Mg ha(-1) without incorporation; (iii) surface-applied broiler litter at 7.8 Mg ha(-1) with immediate incorporation; and (iv) inorganic fertilizer N (urea ammonium nitrate, 32% N) and inorganic fertilizer P (triple superphosphate) at the recommended rate. Phosphorus was surface appliedat 25 kg ha(-1) and N was injected at 101 kg ha(-1) into the soil using a commercial liquid fertilizer applicator. Runoff was collected from small runoff plots (2.4 m by 1.6 m) established at the bottom side of main plots (13.7 m by 6.0 m). Incorporation of broiler litter reduced total N (TN), NO3-N, water soluble P (WSP), and total P (TP) concentrations in runoffby 35, 25, 61, and 64%, respectively, and litter-associated bacteria by two to three orders of magnitude compared with unincorporated treatment. No significant difference in total suspended solids (TSS) in runoffwas obtained between incorporated and unincorporated treatments. Incorporation of broiler litter into the surface soil in the no-till system immediately after application minimized the potential risk for surface nutrient losses and bacteria transport in runoff.     

Spatial distribution of enhanced atrazine degradation across northeastern Colorado cropping systems

Reports of enhanced atrazine degradation and reduced residual weed control have increased in recent years, sparking interest in identifying factors contributing to enhanced atrazine degradation. The objectives of this study were to (i) assess the spatial distribution of enhanced atrazine degradation in 45 commercial farm fields in northeastern Colorado (Kit Carson, Larimer, Logan, Morgan, Phillips, and Yuma counties) where selected cultural management practices and soil bio-chemo-physical properties were quantified; (ii) utilize Classification and Regression Tree (CART) Analysis to identify cultural management practices and (or) soil bio-chemophysical attributes that are associated with enhanced atrazine degradation; and (iii) translate our CART Analysis into a model that predicts relative atrazine degradation rate (rapid, moderate, or slow) as a function of known management practices and (or) soil properties. Enhanced atrazine degradation was widespread within a 300-km radius across northeastern Colorado, with approximately 44% of the fields demonstrating rapid atrazine degradation activity (laboratory-based dissipation time halflife [DT50] < 3 d). The most rapid degradation rates occurred in fields that received the most frequent atrazine applications. Classification and Regression Tree Analysis resulted in a prediction model that correctly classified soils with rapid atrazine DT50 80% of the time and soils with slow degradation (DT50 > 8 d) 62.5% of the time. Significant factors were recent atrazine use history, soil pH, and organic matter content. The presence/absence of atzC polymerase chain reaction (PCR) product was not a significant predictor variable for atrazine DT50. In conclusion, enhanced atrazine degradation is widespread in northeastern Colorado. If producers know their atrazine use history, soil pH, and OM content, they should be able to identify fields exhibiting enhanced atrazine degradation using our CART Model.     

Microbiological quality of roof-harvested rainwater and health risks: a review

Roof-harvested rainwater (RHRW) has been considered an effective alternative water source for drinking and various nonpotable uses in a number of countries throughout the world. The most significant issue in relation to using untreated RHRW for drinking or other potable uses, however, is the potential public health risks associated with microbial pathogens. This paper reviews the available research reporting on the microbial quality of RHRW and provides insight on the capacity of fecal indicator bacteria to monitor health risks and disease outbreaks associated with the consumption of untreated RHRW. Several zoonotic bacterial and protozoan pathogens were detected in individual and communal rainwater systems. The majority of the studies reported in the literature assessed the quality of rainwater on the basis of the presence or absence of specific pathogens, with little information available regarding the actual numbers of such pathogens. In addition, no information is available concerning the ongoing prevalence of different pathogens in RHRW over time. The published data suggest that the microbial quality of RHRW should be considered less than that expected for potable water and that the commonly used indicators may not be suitable to indicate the presence of pathogens in RHRW. Several case control studies established potential links between gastroenteritis and consumption of untreated RHRW. Therefore, health risks assessment models, such as those using Quantitative Microbial Risk Assessment, should be used to manage and mitigate health risks associated with drinking and nonpotable uses of RHRW.     

Green shipping practices in the shipping industry: Conceptualization, adoption, and implications

There have been increasing concerns about the adverse impacts on the environment caused by cargo movement in international trade. Different stakeholders ranging from shippers and carriers to government bodies and international communities have expressed worries about the environmental impacts brought by shipping related activities. The pollution and waste created in the shipping processes have imposed environmental burdens and accelerated resource depletion. The situation is set to worsen in the face of intensifying trade globalization, which has contributed to sustained growth in international shipping activities. To help protect the environment, many shipping firms have taken the initiative to find ways to lessen the environmental damage of their operations while enhancing their performance. The objective of this study is to examine the environmental awareness and the environmental measures taken in the shipping industry. We propose a conceptual framework for evaluating green shipping practices and develop several propositions stating the conditions under which shipping firms would behave in an environmentally responsible manner. We conclude with managerial and policy implications of the conceptual framework to promote green shipping practices in the shipping industry.