Sorption of inorganic and total phosphorus from dairy and swine slurries to soil

Understanding P sorption from animal manures is essential to formulate best management practices with regard to land application of manure from the standpoint of crop production and environmental quality. Little research has focused on the construction of P sorption isotherms where the P source is manure. The objectives of this study were to: (i) develop a procedure to characterize how inorganic P (P(i)) and total P (P(t)) from dairy slurry and swine slurry sorbs to soil; and (ii) compare the sorption characteristics of P(i) and P(t) where the P source was dairy slurry, swine slurry, or potassium phosphate (KH2PO4). Sorption solutions were prepared in 0.1 M KCl at pH 6 and equilibrated with soils at a 1:25 (w/v) soil/solution ratio for 24 h. Inorganic P, P(t), Al, and Fe in the equilibrated solutions were measured. For all soils, P(i) and P(t) sorption capacity of dairy slurry was greater than KH2PO4. Total P sorption capacity of swine slurry was greater than KH2PO4, while P(i) sorption capacity was less than KH2PO4. Overall, P(i) and P(t) sorption strengths of the manure slurries were less than or equal to KH2PO4. Increased P(i) sorption from dairy slurry was correlated with Fe and Al desorption. Reduction of P(i) sorption capacity from swine slurry was related to preferential sorption of organic P. Additional studies need to be conducted to determine how differences in P sorption between manures and fertilizer impact in-field P availability to a crop and potential for losses in runoff water.     

Measurements show that marginal wells are a disproportionate source of methane relative to production

ABSTRACT

Oil and natural gas wells are a prominent source of the greenhouse gas methane (CH₄), but most measurements are from newer, high producing wells. There are nearly 700,000 marginal “stripper” wells in the US, which produce less than 15 barrels of oil equivalent (BOE) d^?1. We made direct measurements of CH₄ and volatile organic carbon (VOC) emissions from marginal oil and gas wells in the Appalachian Basin of southeastern Ohio, all producing < 1 BOE d^?1. Methane and VOC emissions followed a skewed distribution, with many wells having zero or low emissions and a few wells responsible for the majority of emissions. The average CH₄ emission rate from marginal wells was 128 g h^?1 (median: 18 g h^?1; range: 0– 907 g h^?1). Follow-up measurements at five wells indicated high emissions were not episodic. Some wells were emitting all or more of the reported gas produced at each well, or venting gas from wells with no reported gas production. Measurements were made from wellheads only, not tanks, so our estimates may be conservative. Stochastic processes such as maintenance may be the main driver of emissions. Marginal wells are a disproportionate source of CH₄ and VOCs relative to oil and gas production. We estimate that oil and gas wells in this lowest production category emit approximately 11% of total annual CH₄ from oil and gas production in the EPA greenhouse gas inventory, although they produce about 0.2% of oil and 0.4% of gas in the US per year.

Implications: Low producing marginal wells are the most abundant type of oil and gas well in the United States, and a surprising number of them are venting all or more of their reported produced gas to the atmosphere. This makes marginal wells a disproportionate greenhouse gas emissions source compared to their energy return, and a good target for environmental mitigation.     

Status and trends of terrestrial arthropod abundance and diversity in the North Atlantic region of the Arctic

Ambio - The Circumpolar Biodiversity Monitoring Programme (CBMP) provides an opportunity to improve our knowledge of Arctic arthropod diversity, but initial baseline studies are required to...     

Entrepreneurial activities in policy implementation: Sweden’s national wind coordinators

Regional Environmental Change - A growing body of literature focuses on how the context in which policy entrepreneurs operate shapes their actions. This study contributes to this perspective by...     

A transformative mission for prioritising nature in Australian cities

Australia is experiencing mounting pressures related to processes of urbanisation, biodiversity loss and climate change felt at large in cities. At the same time, it is cities that can take the leading role in pioneering approaches and solutions to respond to those coupling emergencies. In this perspective piece we respond to the following question: What are the required transformations for prioritising, valuing, maintaining and embracing nature in cities in Australia? We adopt the mission framework as an organising framework to present proposed pathways to transform Australian cities as nature-positive places of the future. We propose three interconnected pathways as starting actions to steer urban planning, policy and governance in Australian cities: First, cities need to establish evidence-based planning for nature in cities and mainstream new planning tools that safeguard and foreground urban nature. Second, collaborative planning needs to become a standard practice in cities and inclusive governance for nature in cities needs to prioritise Aboriginal knowledge systems and practices as well as look beyond what local governments can do. Third, for progressing to nature-positive cities, it is paramount to empower communities to innovate with nature across Australian cities. Whilst we focus on Australian cities, the lessons and pathways are broadly applicably globally and can inspire science-policy debates for the post COP15 biodiversity and COP26 climate change implementation processes.     

Creating an integrated historical record of extreme particulate air pollution events in Australian cities from 1994 to 2007

Epidemiological studies of exposure to vegetation fire smoke are often limited by the availability of accurate exposure data. This paper describes a systematic framework for retrospectively identifying the cause of air pollution events to facilitate a long, multicenter analysis of the public health effects of vegetation fire smoke pollution in Australia. Pollution events were statistically defined as any day at or above the 95th percentile of the 24-hr average concentration of particulate matter (PM). These were identified for six cities from three distinct ecoclimatic regions of Australia. The dates of each event were then crosschecked against a range of information sources, including online newspaper archives, government and research agency records, satellite imagery, and aerosol optical thickness measures to identify the cause for the excess particulate pollution. Pollution events occurred most frequently during summer for cities in subtropical and arid regions and during winter for cities in temperate regions. A cause for high PM on 67% of days examined in the city of Sydney was found, and 94% of these could be attributed to landscape fire smoke. Results were similar for cities in other subtropical and arid locations. Identification of the cause of pollution events was much lower in colder temperate regions where fire activity is less frequent. Bushfires were the most frequent cause of extreme pollution events in cities located in subtropical and arid regions of Australia. Although identification of pollution episodes was greatly improved by the use of multiple sources of information, satellite imagery was the most useful tool for identifying bushfire smoke pollution events.     

Fractionation and spectroscopic properties of fulvic acid and its extract

Novel results were obtained when a fulvic acid was isolated from Acros humic acid and fractionated by traditional preparative thin-layer chromatography. Eight colorful bands were directly viewed and analyzed showing very different fluorescence and absorption properties. The fluorescence quantum yield of the bands ranged from 2% to 9.4%, significantly higher than that of natural humic substances. An aqueous fulvic acid solution was also extracted with methylene chloride (CH(2)Cl(2)) by continuous liquid-liquid extraction. The CH(2)Cl(2) extract was further fractionated by thin-layer chromatography. Eleven highly fluorescent colorful bands and six weakly fluorescent bands were observed and examined. UV-vis absorption and fluorescence (including 3D matrix) spectra and fluorescence quantum yields revealed that each band still represented a mixture of compounds. Moreover, substantial differences in optical properties were observed among bands. A single band possessed the highest fluorescence quantum yield (6%) and highest specific fluorescence (fluorescence/mass), and accounted for 21% of the total fluorescence of the extract. The mass of individual bands varied from 1.6% to 14.1% of the total materials recovered. Components of all fractions were grouped into 11 fluorophore families according to their maxima on 3D matrix fluorescence spectra. No component is dominant in the whole fulvic acid or extracted portion in terms of optical properties. Over 40 natural products are proposed for model chromophores.     

Assessment of Changes in Stream and Riparian Conditions of the Marys River Basin,Nevada1

Abstract: Stream and riparian managers must effectively allocate limited financial and personnel resources to monitor and manage riparian ecosystems. They need to use management strategies and monitoring methods that are compatible with their objectives and the response potential of each stream reach. Our objective is to help others set realistic management objectives by comparing results from different methods used to document riparian recovery across a diversity of stream types. The Bureau of Land Management Elko Field Office, Nevada, used stream survey, riparian proper functioning condition (PFC) assessment, repeat photographic analysis, and stream and ecological classification to study 10 streams within the Marys River watershed of northeast Nevada during all or parts of 20 years. Most riparian areas improved significantly from 1979 to 1992‐1993 and then additionally by 1997‐2000. Improvements were observed in riparian and habitat condition indices, bank cover, and stability, pool quality, bank angle, and depth of undercut bank. Interpretation of repeat photography generally confirmed results from stream survey and should be part of long‐term riparian monitoring. More attributes of Rosgen stream types C and E improved than of types B and F. A and Gc streams did not show significant improvement. Alluvial draws and alluvial valleys improved in more ways than V‐erosional canyons and especially V‐depositional canyons. Stream survey data could not be substituted for riparian PFC assessment. Riparian PFC assessments help interpret other data.     

Innovation in the Knowledge Age: implications for collaborative science

Current trends validate the notion that multifaceted, multimodal interdisciplinary collaborations lead to increased research productivity in publications and citations, compared to those achieved by individual researchers. Moreover, it may be that scientific breakthroughs are increasingly achieved by interdisciplinary research teams. Nonetheless, despite the perceived importance of collaboration and its bibliometric benefits, today’s scientists are still trained to be autonomous, work individually, and encourage their graduate students to do the same—perpetuating values which impede the creation of collaborative space between disciplines. As a consequence, scientists working in teams typically report serious obstacles to collaboration. This paper builds off of recent recommendations from a 2015 National Academies report on the state of team science which emphasizes greater definition of roles, responsibility, accountability, goals, and milestones. However, these recommendations do not address the subjective, relational components of collaboration which can drive innovation and creativity. The relational side of collaboration is key to understanding the capacity and capabilities of the knowledge workers, such as scientists and engineers, who comprise interdisciplinary research teams. The authors’ recommendations, grounded in organizational communication and knowledge worker literature, include a renewed focus on the process of organizing through communication rather than focusing on organization as an outcome or consequence of teamwork, leading and cultivating team members rather than managing them, and the need to address self-driven, rather than external, motivations to engage in knowledge work.     

Water Supply Reliability Tradeoffs between Removing Reservoir Storage and Improving Water Conveyance in California

Population growth, climate change, aging infrastructure, and changing societal values alter how water must be managed in the 21st Century. O'Shaughnessy Dam, located in Yosemite National Park, has been identified as a possible candidate for dam removal. It is a component of San Francisco's Hetch Hetchy System and is operated for water supply and hydropower. This article describes a spatially scaled approach to analyze water reliability without O'Shaughnessy Dam, but with improved water conveyance between the Hetch Hetchy System and existing reservoirs and aqueducts at the watershed, regional Bay Area, and statewide scales. It broadens previous research to highlight larger scale implications of removing O'Shaughnessy Dam and evaluates the role of improved water conveyance for water management. CALifornia Value Integrated Network, a large‐scale hydro‐economic model evaluates intertied water management using estimated urban and agricultural water demands for year 2050 with 72‐year historical and warm, dry hydrologic conditions. Results suggest that O'Shaughnessy Dam can be removed with additional conveyance at any spatial scale while maintaining water reliability. With a warm, dry climate, water reliability, and storage decline, indicating removing O'Shaughnessy Dam may have less effect on water management than climate change when conveyance is improved between the Hetch Hetchy System and nearby systems. Improving water conveyance can sometimes substitute for water storage in storage‐rich watersheds.