Nitrogen use in the United States from 1961-2000 and potential future trends

Nitrogen inputs to the US from human activity doubled between 1961 and 1997, with most of the increase in the 1960s and 1970s. The largest increase was in use of inorganic N fertilizer, but emissions of NOx from fossil-fuel combustion also increased substantially. In 1961, N fixation in agricultural systems was the largest single source of reactive N in the US. By 1997, even though N fixation had increased, fertilizer use and NOx emissions had increased more rapidly and were both larger inputs. In both 1961 and 1997, two thirds of reactive N inputs were denitrified or stored in soils and biota, while one third was exported. The largest export was in riverine flux to coastal oceans, followed by export in food and feeds, and atmospheric advection to the oceans. The consumption of meat protein is a major driver behind N use in agriculture in the US Without change in diet or agricultural practices, fertilizer use will increase over next 30 years, and fluxes to coastal oceans may increase by another 30%. However, substantial reductions are possible.     

Past,present, and future use of phosphorus in Chinese agriculture and its influence on phosphorus losses

Large inputs of phosphorus (P) in chemical fertilizers and feed supplements since 1978 have improved soil P status in arable land in China, but have also created challenges by increasing P concentrations in manure and exacerbating water quality degradation. Arable land in China can be divided into five management zones based on soil P chemistry, with 15–92 % of arable land having lower P status than the agronomic optimum and 0.3–7.2 % having severe risks of P leaching losses. A scenario analysis of soil P budget and agronomic P demand during 2011–2030 highlighted the great pressure China faces in sustainable P management and the need for drastic changes in current practices. This includes new policies to reduce P supplementation of feed and improved P use efficiency by livestock and programs to expand the adoption of appropriate fertilization, soil conservation, and drainage management practices to minimize P losses.     

Phosphorus recovery from fosfomycin pharmaceutical wastewater by wet air oxidation and phosphate crystallization

Fosfomycin pharmaceutical wastewater contains highly concentrated and refractory antibiotic organic phosphorus (OP) compounds. Wet air oxidation (WAO)-phosphate crystallization process was developed and applied to fosfomycin pharmaceutical wastewater pretreatment and phosphorus recovery. Firstly, WAO was used to transform concentrated and refractory OP substances into inorganic phosphate (IP). At 200 °C, 1.0 MPa and pH 11.2, 99% total OP (TOP) was transformed into IP and 58% COD was reduced. Subsequently, the WAO effluent was subjected to phosphate crystallization process for phosphorus recovery. At Ca/P molar ratio 2.0:1.0 or Mg/N/P molar ratio 1.1:1.0:1.0, 99.9% phosphate removal and recovery were obtained and the recovered products were proven to be hydroxyapatite and struvite, respectively. After WAO-phosphate crystallization, the BOD/COD ratio of the wastewater increased from 0 to more than 0.5, which was suitable for biological treatment. The WAO-phosphate crystallization process was proven to be an effective method for phosphorus recovery and for fosfomycin pharmaceutical wastewater pretreatment.     

Global potential of phosphorus recovery from human urine and feces

This study geospatially quantifies the mass of an essential fertilizer element, phosphorus, available from human urine and feces, globally, regionally, and by specific country. The analysis is performed over two population scenarios (2009 and 2050). This important material flow is related to the presence of improved sanitation facilities and also considers the global trend of urbanization. Results show that in 2009 the phosphorus available from urine is approximately 1.68 million metric tons (with similar mass available from feces). If collected, the phosphorus available from urine and feces could account for 22% of the total global phosphorus demand. In 2050 the available phosphorus from urine that is associated with population increases only will increase to 2.16 million metric tons (with similar mass available from feces). The available phosphorus from urine and feces produced in urban settings is currently approximately 0.88 million metric tons and will increase with population growth to over 1.5 million metric tons by 2050. Results point to the large potential source of human-derived phosphorus in developing regions like Africa and Asia that have a large population currently unserved by improved sanitation facilities. These regions have great potential to implement urine diversion and reuse and composting or recovery of biosolids, because innovative technologies can be integrated with improvements in sanitation coverage. In contrast, other regions with extensive sanitation coverage like Europe and North America need to determine how to retrofit existing sanitation technology combined that is combined with human behavioral changes to recover phosphorus and other valuable nutrients.     

Energy recovery from waste by use of fluidized-bed technology

Revolving type fluidized-bed technology, developed by Ebara Corp., is installed in more than 100 facilities worldwide. The technology is applied for waste, coal and in situations where a conventional fluidized bed is difficult to use. Waste and/or coal can be treated and valuable energy can be recovered from a non-renewable source. This paper describes the application of the revolving fluidized bed for waste, coal and tyres.     

Phosphorus removal and recovery: state of the science and challenges

Environmental Science and Pollution Research - Phosphorus is one of the main nutrients required for all life. Phosphorus as phosphate form plays an important role in different cellular processes....     

Current and future perspectives on energy use and environmental impact

Energy consumption throughout the world contributes to pollution, environmental deterioration, and greenhouse gas emissions. Increases in energy consumption are usually driven by population growth and economic development that tends to increase energy use per capita. Thus, the projected increase in population in the near future, and the economic development that is likely in many countries, have serious implications for the environment. Since the early 1980s the relationship between energy use and environmental impact has received attention, and a number of activities have focused on this topic. In this paper, four important areas related to current and future patterns of environmental impact are introduced and discussed in detail: environmental impact, energy consumption, energy efficiency and conservation, and fuel substitution. We conclude that further political, economic and institutional changes from the standpoint of environmental impact appear to be necessary for future energy policies. To this end, energy efficiency improvements and renewable energy resources can play important roles in controlling and reducing environmental impact.     

Still present after all these years: persistence plus potential toxicity raise questions about the use of atrazine

As one of the worlds’ most heavily applied herbicides, atrazine is still a matter of controversy. Since it is regularly found in ground and drinking water, as well as in sea water and the ice of remote areas, it has become the subject of continuous concern due to its potential endocrine and carcinogenic activity. Current findings prove long-held suspicions that this compound persists for decades in soil. Due to the high amount applied annually all over the world, the soil burden of this compound is considered to be tremendous, representing a potential long-term threat to the environment. The persistence of chemicals such as atrazine has long been underestimated: Do we need to reconsider the environmental risk?     

Microwave treatment and struvite recovery potential of dairy manure

Microwave digestion of liquid dairy manure was tested for the release of nutrients, such as orthophosphates, ammonia-nitrogen, magnesium, calcium and potassium, both with and without the aid of an oxidizing agent (hydrogen peroxide). The orthophosphate to total phosphorus ratio of the manure increased from 21% to greater than 80% with 5 minutes of microwave treatment. More than 36% of total chemical oxygen demand (t-COD) of the manure was reduced when microwave digestion was assisted with peroxide addition. In addition, the volatile fatty acids (VFAs) distribution shifted to simpler chain acids (acetic acid in particular) with an increase in operating temperature. In the second part of the study, digested manure with increased soluble phosphate was tested for the recovery of struvite (magnesium ammonium phosphate) at different pH. It was found that up to 90% of orthophosphate can be removed from the solution. Overall, it was concluded that the oxidizing agent-assisted microwave digestion process can be used upstream of anaerobic digestion, following which the anaerobically digested manure can be used for struvite recovery. Thus, this microwave digestion process presents the potential for enhanced efficiencies in both manure digestion and struvite recovery.     

Microwave treatment and struvite recovery potential of dairy manure

Microwave digestion of liquid dairy manure was tested for the release of nutrients, such as orthophosphates, ammonia-nitrogen, magnesium, calcium and potassium, both with and without the aid of an oxidizing agent (hydrogen peroxide). The orthophosphate to total phosphorus ratio of the manure increased from 21% to greater than 80% with 5 minutes of microwave treatment. More than 36% of total chemical oxygen demand (t-COD) of the manure was reduced when microwave digestion was assisted with peroxide addition. In addition, the volatile fatty acids (VFAs) distribution shifted to simpler chain acids (acetic acid in particular) with an increase in operating temperature. In the second part of the study, digested manure with increased soluble phosphate was tested for the recovery of struvite (magnesium ammonium phosphate) at different pH. It was found that up to 90% of orthophosphate can be removed from the solution. Overall, it was concluded that the oxidizing agent-assisted microwave digestion process can be used upstream of anaerobic digestion, following which the anaerobically digested manure can be used for struvite recovery. Thus, this microwave digestion process presents the potential for enhanced efficiencies in both manure digestion and struvite recovery.     

Environmental threat and change detection in saline lakes from 1960 to 2021: background,present, and future

Environmental Science and Pollution Research - Saline lakes are internationally known for unique chemical compositions, incorporate assorted foliage, and give a few biological system benefits and...     

Rural landscape, production and human consumption: past, present and future

Production and consumption of food and in a rural area over the last 400 years were reconstructed for a parish in south east Sweden. This was based on a number of different data sources, including historical maps and official demographic and agricultural statistics. Changes in population (and thus consumption) and the production from arable land and livestock were calculated and used to provide an estimate of the area's supply and demand over time, and of the historical sustainability of the area. Overall food productivity was remarkably constant over time, at approximately 0.04 kgC m(-2) y(-1), despite recent changes in population size and the area of cultivated land. The empirical results from the past and the present, together with the future land changes due to shoreline displacement were used to predict the situation in the future. These final estimates can be used in the assessment of risk for exposure to contaminated food for the future population in the area.     

Process evaluation for optimization of EDTA use and recovery for heavy metal removal from a contaminated soil

This study aimed to establish an optimized, closed loop application of ethylenediaminetetraacetic acid (EDTA) in heavy metal removals from a contaminated soil through integrating EDTA recovery/regeneration and metal precipitation processes in the treatment train. Three divalent heavy metals were investigated, namely, Pb, Cd, and Ni. The extractability of the metals by EDTA followed the decreasing order of CdPb>Ni. The first part of this study was to search for the optimal use of the fresh EDTA in removing these heavy metals from the contaminated soil. The second part of this study was devoted to the recovery/regeneration of the spent EDTA which followed the sequential processes involving (1) complex destabilization by adding ferric ion (Fe(III)) to liberate Pb, Cd, and Ni, (2) precipitation of the liberated Pb, Cd, and Ni in phosphate (PO4(3-)) forms, and (3) precipitation of the excess Fe(III) which eventually produced free EDTA for reuse. The process variables were dosages of Fe(III) and PO4(3-), pH and reaction times. Laborious trial experiments would be needed in searching for the optimum conditions for the above processes. To expedite this exercise, a geochemical equilibrium model, MINTEQA2, was used to find the thermodynamically favorable conditions for recoveries of both EDTA and heavy metals. This was then followed by experimental examination of the process kinetics to observe for the optimal reaction time for each thermodynamically favorable process. This study revealed that 2 h of reaction time each for the complex destabilization reaction and the metal phosphate precipitation reaction was sufficient to achieve equilibrium. With the optimized process condition identified in this study, a total of 95%, 89% and 90% of the extracted Pb, Cd and Ni, respectively, could be precipitated from the spent EDTA solution, with 84% EDTA recovery. The reused EDTA maintained more than 90% of its preceding extraction power in each cycle of reuse.     

Assessment of present and future risk to Italian forests and human health: Modelling and mapping

A review of ozone pollution in Italy shows levels largely above the thresholds established by EU regulation for vegetation and human health protection. The Italian air quality monitoring network appears quantitatively inadequate to cover all the territorial surface, because of scarcity and unequal distribution of monitoring sites. By applying the integrated assessment model RAINS-Italy to the year 2000, the whole of Italy exceeds the AOT40 critical level for forest, while Northern and central areas show strong potential of O₃ impact on human health with ∼11% of territory >10 O₃-induced premature deaths. Two scenarios for the year 2020, the Current Legislation and the Maximum Technical Feasible Reduction, show a reduction of AOT40Forest by 29% and 44%, SOMO35 by 31% and 47%, and O₃-induced premature deaths by 32% and 48%, compared to 2000. RAINS-Italy can be used to improve the map quality and cover areas not reached by the national monitoring network.     

Phosphorus Flows to and from Swedish Agriculture and Food Chain

Phosphorus flows in Swedish agriculture and food chain were studied by material flow analysis. The system studied included agriculture, food consumption, related waste and wastewater from private households and municipal wastewater treatment plants. Swedish farmland had net annual phosphorus inputs of ~12 600 metric tons (4.1 kg P ha⁻¹) in 2008–2010. The total import of phosphorus in food and feed to Sweden exceed imports of phosphorus in fertilizers. Despite strict animal density regulations relating to manure phosphorus content, phosphorus is accumulating on Swedish animal farms. The total quantity of manure produced greatly exceeds imported mineral phosphorus fertilizer and almost equals total phosphorus inputs to Swedish farmland.     

Role of multidrug resistance-associated proteins in cancer therapeutics: past,present, and future perspectives

Environmental Science and Pollution Research - Cancer, a major public health problem, is one of the world’s top leading causes of death. Common treatments for cancer include cytotoxic...     

Comparison of the toxicogenetic potential of sewage sludges from different treatment processes focusing agricultural use

Environmental Science and Pollution Research - A problem that has been dragging in recent decades is the final disposal of the waste produced in the wastewater treatment process. In addition to its...     

Fish status survey of Nordic lakes: effects of acidification,eutrophication and stocking activity on present fish species composition

The status of fish populations in 3821 lakes in Norway, Sweden and Finland was assessed in 1995-1997. The survey lakes were chosen by stratified random sampling from all (126 482) Fennoscandian lakes > or = 0.04 km2. The water chemistry of the lakes was analyzed and information on fish status was obtained by a postal inquiry. Fish population losses were most frequent in the most highly acidified region of southern Norway and least common in eastern Fennoscandia. According to the inquiry results, the number of lost stocks of brown trout (Salmo trutta), roach (Rutilus rutilus), Arctic char (Salvelinus alpinus) and perch (Perca fluviatilis) was estimated to exceed 10000. The number of stocks of these species potentially affected by the low alkalinity of lake water was estimated to exceed 11000. About 3300 lakes showed high total phosphorus (> 25 microg L(-1)) and cyprinid dominance in eastern Fennoscandia, notably southwestern Finland. This survey did not reveal any extinction of fish species due to eutrophication. One-third of the lakes had been artificially stocked with at least one new species, most often brown trout, whitefish (Coregonus lavaretus s.l.), Arctic char, rainbow trout (Oncorhynchus mykiss), pike-perch (Stizostedion lucioperca), grayling (Thymallus thymallus), pike (Esox lucius), bream (Abramis brama), tench (Tinca tinca) and European minnow (Phoxinus phoxinus). The number of artificially manipulated stocks of these species in Fennoscandian lakes was estimated to exceed 52000. Hence, the number of fish species occurring in Nordic lakes has recently been changed more by stockings than by losses of fish species through environmental changes such as acidification.     

Phosphorus removal from livestock effluents: recent technologies and new perspectives on low-cost strategies

Environmental Science and Pollution Research - Phosphorus is an essential element in the food production chain, even though it is a non-renewable and limited natural resource, which is going to run...