Quantification of nitrogen balance components in a commercial broiler barn

Characterizing the respective nitrogen (N) use efficiency requires understanding the N flow of inputs and outputs from a commercial broiler barn. In this study, an N mass balance was performed for one entire growing cycle. The objectives were to quantify, sample, and analyze all N components entering and leaving the barn. The N from feed, chickens, and bedding material was considered as inputs, the outputs included the N accretion in mature broilers, the total N emissions (NTNE), the N accumulation in litter, and the N of mortality. Of particular relevance was the determination of an appropriate method to mirror the heterogenic texture of the litter. Litter samples were collected weekly according to a defined procedure. The major N input was feed N, accounting for 99% of the total N input. After the 36-day growing cycle, the N outputs were portioned as follows: 59% (1741.3 kg N) in mature broilers, 37% (1121.3 kg N) accumulated in litter, and 4% in NTNE (114.3 kg N). The N accumulations in broiler tissue and litter agree well with other studies. The measured emissions were consistently lower compared to other references, due to the fact that these references were mainly based on studies where broilers were raised on built-up litter. In contrast to in situ quantified N emissions in this study, other published values were assumed to be the difference of N between inputs and outputs. This study illustrates that extensive sampling of litter is a prerequisite for calculating litter masses. The accurate specification of the litter texture proved to be crucial within the mass balance approach. With this information, the feasible improvements within management practices can be identified

Luftgeschwindigkeit und Hitzebelastung im Milchviehstall - Auswirkungen auf das Tierwohl

Das Stallklima hat einen wesentlichen Einfluss auf das Wohlbefinden und die Leistungsfähigkeit von Milchkühen. In der vorliegenden Untersuchung wurden Stallklimamessungen innerhalb und außerhalb eines frei gelüfteten Milchviehstalls, mit dem Fokus auf der Luftgeschwindigkeit im Fress- und Liegebereich, durchgeführt. Die Ergebnisse zeigten, dass die untersuchten Stallbereiche aufgrund der heterogen auftretenden Luftgeschwindigkeiten unterschiedlich belüftet wurden. Des Weiteren wurden die Stallklimamessungen mit physiologischen Tierparametern korreliert, um sie in Bezug auf das thermische Wohlbefinden der Tiere interpretieren zu können. An heißen Tagen wichen die analysierten Parameter deutlich von den übrigen Tagen ab.The investigation of barn climate and heat stress is important with regard to both welfare of dairy cows and performance. For this reason climate measurements in- and outside of a natural cross ventilated dairy barn have been conducted. Special emphasis was devoted to measurements on air speed within the animal occupied zone of the stable. The air speed was heterogeneously distributed and the results showed areas which were permanently less ventilated than others. However, climate measurements should be correlated to physiological animal parameters in order to interpret the barn conditions in respect of thermal comfort of the animals. On hot days, the parameters analyzed showed clear differences from the other days

Field inter-comparison of eleven atmospheric ammonia measurement techniques

Eleven instruments for the measurement of ambient concentrations of atmospheric ammonia gas (NH3), based on eight different measurement methods were inter-compared above an intensively managed agricultural field in late summer 2008 in Southern Scotland. To test the instruments over a wide range of concentrations, the field was fertilised with urea midway through the experiment, leading to an increase in the average concentration from 10 to 100 ppbv. The instruments deployed included three wet-chemistry systems, one with offline analysis (annular rotating batch denuder, RBD) and two with online-analysis (Annular Denuder sampling with online Analysis, AMANDA; AiRRmonia), two Quantum Cascade Laser Absorption Spectrometers (a large-cell dual system; DUAL-QCLAS, and a compact system; c-QCLAS), two photo-acoustic spectrometers (WaSul-Flux; Nitrolux-100), a Cavity Ring Down Spectrosmeter (CRDS), a Chemical Ionisation Mass Spectrometer (CIMS), an ion mobility spectrometer (IMS) and an Open-Path Fourier Transform Infra-Red (OP-FTIR) Spectrometer. The instruments were compared with each other and with the average concentration of all instruments. An overall good agreement of hourly average concentrations between the instruments (R2>0.84), was observed for NH3 concentrations at the field of up to 120 ppbv with the slopes against the average ranging from 0.67 (DUAL-QCLAS) to 1.13 (AiRRmonia) with intercepts of −0.74 ppbv (RBD) to +2.69 ppbv (CIMS). More variability was found for performance for lower concentrations (<10 ppbv). Here the main factors affecting measurement precision are (a) the inlet design, (b) the state of inlet filters (where applicable), and (c) the quality of gas-phase standards (where applicable). By reference to the fast (1 Hz) instruments deployed during the study, it was possible to characterize the response times of the slower instruments

Field inter-comparison of eleven atmospheric ammonia measurement techniques

Eleven instruments for the measurement of ambient concentrations of atmospheric ammonia gas (NH3), based on eight different measurement methods were inter-compared above an intensively managed agricultural field in late summer 2008 in Southern Scotland. To test the instruments over a wide range of concentrations, the field was fertilised with urea midway through the experiment, leading to an increase in the average concentration from 10 to 100 ppbv. The instruments deployed included three wet-chemistry systems, one with offline analysis (annular rotating batch denuder, RBD) and two with online-analysis (Annular Denuder sampling with online Analysis, AMANDA; AiRRmonia), two Quantum Cascade Laser Absorption Spectrometers (a large-cell dual system; DUAL-QCLAS, and a compact system; c-QCLAS), two photo-acoustic spectrometers (WaSul-Flux; Nitrolux-100), a Cavity Ring Down Spectrosmeter (CRDS), a Chemical Ionisation Mass Spectrometer (CIMS), an ion mobility spectrometer (IMS) and an Open-Path Fourier Transform Infra-Red (OP-FTIR) Spectrometer. The instruments were compared with each other and with the average concentration of all instruments. An overall good agreement of hourly average concentrations between the instruments (R2>0.84), was observed for NH3 concentrations at the field of up to 120 ppbv with the slopes against the average ranging from 0.67 (DUAL-QCLAS) to 1.13 (AiRRmonia) with intercepts of −0.74 ppbv (RBD) to +2.69 ppbv (CIMS). More variability was found for performance for lower concentrations (<10 ppbv). Here the main factors affecting measurement precision are (a) the inlet design, (b) the state of inlet filters (where applicable), and (c) the quality of gas-phase standards (where applicable). By reference to the fast (1 Hz) instruments deployed during the study, it was possible to characterize the response times of the slower instruments

Landwirtschaftliches Ammoniak in der Atmosphäre: Transport, Monitoring und Umweltauswirkungen

Die Landwirtschaft, speziell die Tierproduktion, ist die Hauptquelle für anthropogen erzeugte Ammoniakemissionen in Europa. Der Grund dafür liegt in einem erhöhten Nahrungsbedarf einer stetig wachsenden Weltbevölkerung. Diese Ammoniak¬emissionen besitzen einen direkten Einfluss auf die angrenzende Umwelt und führen zur Beeinträchtigung der Luftqualität bis hin zu massiver Geruchsbelästigung. Ein Ziel dieser Dissertation ist es, die Transport- und Ausbreitungsprozesse von Ammoniak (NH3) zu beschreiben sowie damit verbundene Monitoring-Methoden und auftretende Umwelteinflüsse zu charakterisieren. Um grundlegende Faktoren zu bestimmen, die einen regulierenden Einfluss auf NH3-Konzentrationen haben, wurden Umweltbedingungen, meteorologische Aspekte und die Betriebsbedingungen der Stallanlagen berücksichtigt. Ein weiterer Aspekt dieser Arbeit liegt in der Untersuchung der Beziehung zwischen NH3-Konzentrationen und der auftretenden Vegetation in unterschiedlichen Entfernungen einer Stallanlage. Für das Monitoring von NH3-Konzentrationen in landwirtschaftlich genutzten Gebieten wurden unterschiedliche Messtechniken entwickelt. Aufgrund der großen Vielzahl an NH3-Messmethoden wurden Vergleichsmessungen unter typischen Feldbedingungen initiiert, um geeignete Geräte für exakte Messungen zu finden. Der hier präsentierte Vergleich umfasst elf Geräte zur Detektion von atmosphärischen NH3-Konzentrationen, die auf acht unterschiedlichen Messmethoden basieren. Die Messungen fanden auf einer intensiv bewirtschafteten landwirtschaftlichen Weidefläche statt. Trotz der überaus guten Übereinstimmung der mit den unterschiedlichen Geräten gemessenen durchschnittlichen NH3-Konzentrationen, bleibt die kontinuierliche Erfassung von NH3-Konzentrationen ein herausforderndes Vorhaben. Transport- und Ausbreitungsprozesse von atmosphärischem NH3 werden durch viele lokale Faktoren beeinflusst. Während der durchgeführten Feldmessungen wurden Hauptfaktoren ausgewählt und evaluiert, die sowohl die Umweltbedingungen und die meteorologischen Aspekte als auch die Betriebsbedingungen der Stallanlagen charakterisieren. Als Untersuchungsobjekt wurde eine große Broilermastanlage gewählt, die typisch für die landwirtschaftliche Landschaft in Deutschland und Europa ist. Mittels multipler linearer Regressionsanalyse (MLR) wurde die Beziehung zwischen zehn Haupteinflussfaktoren und den gemessenen NH3-Konzentrationen analysiert. Hinsichtlich der Anwendung geeigneter Monitoring-Methoden stellt die Wahl des Standortes für die Beobachtungspunkte einen entscheidenden Aspekt dar, um wirklich belastbare und sinnvolle Messergebnisse zu erzielen. Das emittierte NH3 wird durch die auftretenden Windrichtungen stark beeinflusst. Dennoch weisen die Ergebnisse der MLR auf einen rück- bzw. abwärtsgerichteten Transport der NH3-angereicherten Luft zum Beobachtungspunkt hin, auch wenn der Wind aus einer Richtung ohne NH3-Quelle weht. Diese Ergebnisse zeigen einen starken Einfluss der durch das vorhandene Lüftungssystem bedingten Austrittshöhe der Abluft aus den Schornsteinen. Während weiterer Versuche an derselben Broilermastanlage wurden die NH3-Emissionen und die daraus resultierenden atmosphärischen NH3-Konzentrationen an fünf Beobachtungspunkten quantifiziert. Zusätzlich erfolgte eine Analyse der auftretenden Vegetation entlang eines Transekts durch ein sich anschließendes Waldgebiet. Die Broilermastanlage als Emissionsquelle bewirkt einen signifikanten Anstieg der atmosphärischen NH3-Konzentrationen in der unmittelbaren Umgebung. Diese erfassten atmosphärischen NH3-Konzentrationen wurden stark durch die auftretenden Windrichtungen beeinflusst. Es ist anzunehmen, dass das unmittelbar angrenzende Waldgebiet eine weiträumige Ausbreitung der Luftverunreinigungen durch die NH3-Emissionen verhindert. Jedoch wird der Wald innerhalb eines Abstandes von ~400 m von der Broilermastanlage durch den erhöhten Eintrag von NH3-Konzentrationen nachteilig beeinträchtigt. Diese Ergebnisse verdeutlichen eine Notwendigkeit von Waldstreifen als Schutzpflanzungen. Sie zeigen aber auch, dass die Umsetzungen weiterer Maßnahmen zur Minderung von NH3-Emissionen notwendig sind.Agriculture and especially the livestock industry is the major source of anthropogenic emissions of ammonia (NH3) in Europe. Ammonia emissions are likely to increase due to the pressure on the food production industry to keep pace with the growing world population. These emissions affect the air quality can cause odour nuisance and have direct impacts on the environment. This thesis focuses on the investigation of transport and dispersion processes of atmospheric NH3. Further aspects take into account the evaluation of relevant monitoring methods and the characterisation of the direct environmental impacts of NH3. The processes involved in transport and dispersion of NH3 are complex. In order to fully understand the underlying and influencing factors, environmental conditions, meteorological aspects and the operational mode of the animal production facilities were considered. The relationship between atmospheric NH3 concentrations and the abundance and diversity of vegetation with increasing distance from the NH3 source was a further issue. For monitoring atmospheric NH3 in agricultural used areas, various different techniques have been developed. Owing to this wide variety of methods, a comparison under typical field conditions was initiated to identify the most suitable instruments for accurate measurements of atmospheric NH3 concentrations above an intensively managed agricultural field. The study presented here included eleven instruments based on eight different measurement methods. Despite the overall good agreement between the average NH3 concentrations measured with the various instruments, a truly continuous NH3 measurement remains a challenging enterprise. The process of dispersion and transport of NH3 is influenced by various local factors. During a field experiment, selected major factors which characterise the atmospheric and meteorological conditions as well as the operational parameters of an animal production facility were evaluated. The animal production facility is represented by a huge broiler farm which is typical for agricultural landscapes in Germany and Europe. By implementing multiple linear regression (MLR) analyses, the relationship between factors-of-influence (FOI) and the measured atmospheric NH3 were analysed. In terms of applying suitable monitoring methods, the location of a monitoring point is essential for a successful and accurate investigation outcome. The emitted NH3 was strongly influenced by the actual wind direction. The sensor at the monitoring point detected NH3 in the air even when the wind blew over an area without sources of NH3. This observation implied that NH3-enriched reverse winds blew back in the direction of the monitoring tower. It also implied that a downward flow of NH3-enriched air reached the measuring device and was detected. These partially unexpected processes should be considered in any future studies focusing on the spatial dispersion of NH3 in the air. For the same broiler farm, NH3 emissions and resulting atmospheric NH3 concentrations at five monitoring points in the immediate vicinity have been quantified. Additionally, vegetation along a transect through an adjacent woodland were analysed. Strongly affected by the occurring wind direction, the broiler farm as a source of NH3 emission significantly increased NH3 concentrations in the immediate vicinity. The adjacent woodland had a positive effect because it may help to retain the air pollution in a small local area. Nevertheless, vegetation was adversely affected within a ~400 m distance from the farm. The outcome of this study illustrates the positive effect of tree belts for a reduction of NH3 concentrations in the vicinity of agricultural sources. It also attempts the need for further implementation of abatement efforts to minimise NH3 emissions

Awassi sheep keeping in the Arabic steppe in relation to nitrous oxide emission from soil

Sheep husbandry is the main source of income for farmers in arid zones. Increasing sheep production on steppes may increase the greenhouse gas production. The objective of this study was to investigate the nitrous oxide (N2O) emissions from the steppes for Awassi sheep keeping and feed cropping in arid zones such as Syria. The methodology developed by the Intergovernmental Panel on Climate Change (IPCC) was used to estimate N2O emissions. A survey was conducted on 64 farms in Syria to gather data for analysis. Precipitation and crop yield data from 2001 to 2009 were also used for calculation and modelling. Sheep-keeping systems, precipitation, year and the region have significant effects on N2O emissions (p < 0.05). Emissions of N2O from lands with extensive, semi-intensive and intensive systems were 0.30 ± 0.093, 0.598 ± 0.113 and 2.243 ± 0.187 kg sheep−1year−1, respectively. Crop production was higher in regions with high precipitation levels, which helped to reduce N2O emissions. Using more residuals of wheat, cotton and soya as feed for sheep in the keeping systems evaluated may decrease the overuse of steppe regions and N2O emissions. Nitrous oxide emissions of N2O from sheep-keeping areas can be reduced by changing sheep-keeping systems and increasing the crop production in arid zones through artificial irrigation

Comparing methane emissions from different sheep-keeping systems in semiarid regions: A case study of Syria

Sheep husbandry represents a significant source of methane (CH4) in semiarid grassland regions such as Syria. However, the contribution of sheep to CH4 emissions in Syria is still unknown. This study was designed to quantify CH4 emissions and identify possible mitigation strategies for their reduction. Methodology developed by the Intergovernmental Panel on Climate Change (IPCC) was used to estimate CH4 emissions. A survey was conducted on 64 farms from different locations in Syria in 2009. Data were collected concerning sheep-keeping systems (SKSs), body mass, milk and wool yield, farm locations, feed rations, periods of grazing on the Steppe, the duration of pasturing on agricultural residuals and time periods when sheep were kept in stables. Using a linear statistical model, the influence of SKS, geographical region and sheep body mass on emitted CH4 were analysed. The results showed that the geographical region, SKS and sheep body mass had significant effects (P < 0.05) on CH4 emissions. According to the model, the mean values of estimated CH4 emissions from extensive, semi-intensive and intensive SKSs were 26 ± 0.9, 22.5 ± 1.3 and 13.5 ± 1.7 kg/sheep year, respectively. In comparing differences between the least square means of CH4 emissions, the extensive and semi-intensive SKSs produced 92% and 66% higher CH4 emissions compared to intensive SKS. The differences in CH4 emissions within the distinct SKSs were attributed to dietary composition. Extensive SKS used a less concentrated feeding regime (98 ± 17 day/year) than semi-intensive SKS (114 ± 47 day/year), and intensive SKS employed concentrated feeding year round. Furthermore, it was observed that sheep with the same body mass produced higher CH4 emissions in extensive SKS than in semi-intensive and intensive SKSs. Moreover, the semi-intensive SKS occupied more natural pastures than extensive SKS, which caused an overuse of the Steppe. Therefore, an effective mitigation strategy involves the use of more digestible feed, which would be accomplished by increasing the quantity of concentrated feed. Owing to unfavourable farming conditions, low-cost nonconventional feeds such as the residuals of wheat and cotton should be used to improve sheep management practices to reduce Steppe overgrazing in the extensive and semi-intensive SKSs of Syria and other semiarid areas