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1.
J Environ Qual ; 52(1): 207-223, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36419334

ABSTRACT

Livestock manure management systems can be significant sources of nitrous oxide (N2 O), methane (CH4 ), and ammonia (NH3 ) emissions. Many studies have been conducted to improve our understanding of the emission processes and to identify influential variables in order to develop mitigation techniques adapted to each manure management step (animal housing, outdoor storage, and manure spreading to land). The international project DATAMAN (http://www.dataman.co.nz) aims to develop a global database on greenhouse gases (N2 O, CH4 ) and NH3 emissions from the manure management chain to refine emission factors (EFs) for national greenhouse gas and NH3 inventories. This paper describes the housing and outdoor storage components of this database. Relevant information for different animal categories, manure types, livestock buildings, outdoor storage, and climatic conditions was collated from published peer reviewed research, conference papers, and existing databases published between 1995 and 2021. In the housing database, 2024 EFs were collated (63% for NH3 , 19.5% for CH4 , and 17.5% for N2 O). The storage database contains 654 NH3 EFs from 16 countries, 243 CH4 EFs from 13 countries, and 421 N2 O EFs from 17 countries. Across all gases, dairy cattle and swine production in temperate climate zones are the most represented animal and climate categories. As for the housing database, the number of EFs for the tropical climate zone is under-represented. The DATAMAN database can be used for the refinement of national inventories and better assessment of the cost-effectiveness of a range of mitigation strategies.


Subject(s)
Ammonia , Greenhouse Gases , Cattle , Animals , Swine , Ammonia/analysis , Manure , Nitrous Oxide/analysis , Livestock , Methane/analysis , Housing, Animal
2.
J Environ Qual ; 50(5): 1005-1023, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34192353

ABSTRACT

Manure application to land and deposition of urine and dung by grazing animals are major sources of ammonia (NH3 ) and nitrous oxide (N2 O) emissions. Using data on NH3 and N2 O emissions following land-applied manures and excreta deposited during grazing, emission factors (EFs) disaggregated by climate zone were developed, and the effects of mitigation strategies were evaluated. The NH3 data represent emissions from cattle and swine manures in temperate wet climates, and the N2 O data include cattle, sheep, and swine manure emissions in temperate wet/dry and tropical wet/dry climates. The NH3 EFs for broadcast cattle solid manure and slurry were 0.03 and 0.24 kg NH3 -N kg-1 total N (TN), respectively, whereas the NH3 EF of broadcast swine slurry was 0.29. Emissions from both cattle and swine slurry were reduced between 46 and 62% with low-emissions application methods. Land application of cattle and swine manure in wet climates had EFs of 0.005 and 0.011 kg N2 O-N kg-1 TN, respectively, whereas in dry climates the EF for cattle manure was 0.0031. The N2 O EFs for cattle urine and dung in wet climates were 0.0095 and 0.002 kg N2 O-N kg-1 TN, respectively, which were three times greater than for dry climates. The N2 O EFs for sheep urine and dung in wet climates were 0.0043 and 0.0005, respectively. The use of nitrification inhibitors reduced emissions in swine manure, cattle urine/dung, and sheep urine by 45-63%. These enhanced EFs can improve national inventories; however, more data from poorly represented regions (e.g., Asia, Africa, South America) are needed.


Subject(s)
Manure , Nitrous Oxide , Ammonia/analysis , Animals , Cattle , Livestock , Nitrous Oxide/analysis , Sheep , Swine , Tropical Climate
3.
J Environ Qual ; 50(2): 513-527, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33331653

ABSTRACT

Nitrous oxide (N2 O), ammonia (NH3 ), and methane (CH4 ) emissions from the manure management chain of livestock production systems are important contributors to greenhouse gases (GHGs) and NH3 emitted by human activities. Several studies have evaluated manure-related emissions and associated key variables at regional, national, or continental scales. However, there have been few studies focusing on the drivers of these emissions using a global dataset. An international project was created (DATAMAN) to develop a global database on GHG and NH3 emissions from the manure management chain (housing, storage, and field) to identify key variables influencing emissions and ultimately to refine emission factors (EFs) for future national GHG inventories and NH3 emission reporting. This paper describes the "field" database that focuses on N2 O and NH3 EFs from land-applied manure and excreta deposited by grazing livestock. We collated relevant information (EFs, manure characteristics, soil properties, and climatic conditions) from published peer-reviewed research, conference papers, and existing databases. The database, containing 5,632 observations compiled from 184 studies, was relatively evenly split between N2 O and NH3 (56 and 44% of the EF values, respectively). The N2 O data were derived from studies conducted in 21 countries on five continents, with New Zealand, the United Kingdom, Kenya, and Brazil representing 86% of the data. The NH3 data originated from studies conducted in 17 countries on four continents, with the United Kingdom, Denmark, Canada, and The Netherlands representing 79% of the data. Wet temperate climates represented 90% of the total database. The DATAMAN field database is available at http://www.dataman.co.nz.


Subject(s)
Manure , Nitrous Oxide , Ammonia/analysis , Animals , Brazil , Canada , Humans , Kenya , Livestock , Methane , New Zealand , Nitrous Oxide/analysis
4.
Animals (Basel) ; 9(11)2019 Nov 13.
Article in English | MEDLINE | ID: mdl-31766132

ABSTRACT

The objective of this work was to evaluate whether changes in time of herbage allocation and herbage mass (HM) (low (L) or medium (M)) modify the diurnal pattern of urinary nitrogen (N) concentration and ruminal ammonia (NH3) of lactating dairy cows. Four Holstein-Friesian cows fitted with rumen cannula were randomly allocated to one of four treatments: 1) low herbage mass in the morning (L-AM) (Access to new herbage allocation after morning milking with a herbage mass (HM) of 2000 kg DM/ha); 2) low herbage mass in the afternoon (L-PM) (Access to new herbage allocation after afternoon milking with a HM of 2000 kg DM/ha); 3) medium herbage mass in the morning (M-AM) (Access to new herbage allocation after morning milking with a HM of 3000 kg DM/ha); and 4) medium herbage mass in the afternoon (M-PM) (Access to new herbage allocation after afternoon milking with a HM of 3000 kg DM/ha). A four by four Latin Square design with four treatments, four cows, and four experimental periods was used to evaluate treatment effects. Rumen NH3 concentration was greater for L-AM compared to L-PM and M-PM at 13:00 and 16:00 h. Urine urea and N concentrations were lower for M-AM compared to L-AM. Urine N concentration was greater for L-AM than other treatments at 10:00 hours and greater for M-PM compared to M-AM at 16:00 hours. Results suggest that maintaining the cows in the holding pen at the milking parlor for two hours after morning grass silage supplementation for L-AM and for two hours after afternoon grass silage supplementation for M-PM, could allow collection of urine from cows at the holding pen and storage of urine in the slurry pit during the time of peak N concentration, returning cows to the pasture at a time of day when urinary N concentration is decreased.

5.
Animals (Basel) ; 9(6)2019 Jun 19.
Article in English | MEDLINE | ID: mdl-31248163

ABSTRACT

The aim of this study was to evaluate the effects of the order of grass silage (GS) and maize silage (MS) supplementation on milk yield, grazing behavior and nitrogen (N) partitioning of lactating dairy cows during autumn. Thirty-six Holstein-Friesian dairy cows were randomly assigned to one of three treatments, and cows remained on these treatments for a 62 days period: (1) MIX; cows supplemented with 3 kg of dry matter (DM) of silage containing 1.5 kg DM of MS and 1.5 kg DM of GS in both the morning and afternoon; (2) GS-MS; cows supplemented with 3 kg DM of GS in the morning and 3 kg DM of MS in the afternoon; (3) MS-GS; cows supplemented with 3 kg DM of MS in the morning and 3 kg DM of GS in the afternoon. All cows received a pasture allowance of 17 kg DM/cow/d and 3 kg DM of concentrate. Grazing time and pasture intake were unaffected by treatment; however, milk production was greater for MS-GS, while milk protein was greater for GS-MS. Urinary N excretion was greater for MS-GS than MIX. In conclusion, MS-GS resulted in high milk yield but also high urinary N excretion, while MIX resulted in low urinary N excretion but also decreased milk yield.

7.
Environ Technol ; 35(17-20): 2237-43, 2014.
Article in English | MEDLINE | ID: mdl-25145176

ABSTRACT

Photocatalytic water splitting for hydrogen and oxygen production requires sacrificial electron donors, for example, organic compounds. Titanium dioxide catalysts doped with platinum, cobalt, tungsten, copper and iron were experimentally tested for the production of hydrogen, oxygen and low molecular weight hydrocarbons from aqueous solutions of humic substances (HS). Platinum-doped catalyst showed the best results in hydrogen generation, also producing methane, ethene and ethane, whereas the best oxygen production was exhibited by P25, followed by copper--and cobalt-containing photocatalysts. Iron-containing photocatalyst produced carbon monoxide as a major product. HS undergoing anoxic photocatalytic degradation produce hydrogen with minor hydrocarbons, and/or oxygen. It appears that better hydrogen yield is achieved when direct HS splitting takes place, as opposed to HS acting as electron donors for water splitting.


Subject(s)
Humic Substances/analysis , Hydrogen/metabolism , Water Purification/methods , Biofuels , Humic Substances/radiation effects , Hydrocarbons/analysis , Hydrocarbons/metabolism , Hydrogen/analysis , Hydrogen-Ion Concentration , Oxygen/analysis , Oxygen/metabolism , Photochemical Processes , Titanium , Water Purification/instrumentation
8.
Nano Lett ; 14(2): 597-603, 2014 Feb 12.
Article in English | MEDLINE | ID: mdl-24443959

ABSTRACT

A rapid increase in anthropogenic emission of greenhouse gases, mainly carbon dioxide, has been a growing cause for concern. While photocatalytic reduction of carbon dioxide (CO2) into solar fuels can provide a solution, lack of insight into energetic pathways governing photocatalysis has impeded study. Here, we utilize measurements of electronic density of states (DOS), using scanning tunneling microscopy/spectroscopy (STM/STS), to identify energy levels responsible for photocatalytic reduction of CO2-water in an artificial photosynthetic process. We introduce desired states in titanium dioxide (TiO2) nanoparticles, using metal dopants or semiconductor nanocrystals, and the designed catalysts were used for selective reduction of CO2 into hydrocarbons, alcohols, and aldehydes. Using a simple model, we provide insights into the photophysics governing this multielectron reduction and design a new composite photocatalyst based on overlapping energy states of TiO2 and copper indium sulfide (CIS) nanocrystals. These nanoparticles demonstrate the highest selectivity for ethane (>70%) and a higher efficiency of converting ultraviolet radiation into fuels (4.3%) using concentrated sunlight (>4 Sun illumination), compared with platinum-doped TiO2 nanoparticles (2.1%), and utilize hot electrons to tune the solar fuel from alkanes to aldehydes. These results can have important implications for the development of new inexpensive photocatalysts with tuned activity and selectivity.


Subject(s)
Biomimetic Materials/chemistry , Carbon Dioxide/chemistry , Metal Nanoparticles/chemistry , Photosynthesis , Titanium/chemistry , Water/chemistry , Biomimetic Materials/radiation effects , Carbon Dioxide/radiation effects , Catalysis , Light , Materials Testing , Metal Nanoparticles/radiation effects , Titanium/radiation effects
9.
Clin Plast Surg ; 33(3): 321-32, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16818091

ABSTRACT

The authors describe four characteristics that determine attractive buttocks in addition to the balanced anatomical dimensions of the maximal point of gluteal projection. Based on this information, defects of the gluteal region can be classified into five types. The most appropriate size and shape of gluteal implants and the proper surgical technique for gluteal augmentation can be chosen by first identifying the buttock type ofa patient. The proposed method of buttock classification helps achieve a gluteal contour that closely matches the standard of beauty.


Subject(s)
Beauty , Buttocks/surgery , Plastic Surgery Procedures/methods , Prostheses and Implants , Female , Humans , Lipectomy
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