Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing,
2023
South Dakota State University
Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing, Tagir Gilmanov, M. W. Demment, B. K. Wylie, K. Akshalov, D. D. Baldocchi, L. Belelli, J. A. Bradford, G. G. Burba, R. L. Coulter, W. A. Dugas, W. E. Emmerich, L. B. Flanagan, A. B. Frank, J. Fuher, M. R. Haferkamp, M. B. Jones, D. A. Johnson, T. Laurila, A. Lohila, T. P. Meyers, P. C. Mielnick, J. A. Morgan, M. Nasyrov, C. E. Owensby, M. S. Pekour, K. Pilegaard, A. Raschi, N. Z. Saliendra, M. J. Sanz, P. L. Sims, R. H. Skinner, J. F. Sousanna, A. E. Suyker, L. L. Tieszen, Z. Tuba, R. Valentini, S. B. Verma, E. A. Laca
IGC Proceedings (1997-2023)
Grasslands cover significant areas in nontropical regions, perform essential biogeochemical functions and represent important natural and agricultural resource. Nevertheless, in contrast to forests and agroecosystems, no flux measurement-based global summary of their CO2 exchange, sequestration potential, and role in mitigation of the greenhouse effect were available.
The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan,
2023
Yamanashi Institute of Environmental Sciences, Japan
The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan, Taisuke Yasuda, Masae Shiyomi, T. Egawa, K. Sei, R. Ishikawa, S. Takahashi
IGC Proceedings (1997-2023)
Spatiotemporal variation in the local immigration and extinction of species in a community may form and change the spatial heterogeneity (SH) of vegetation but few studies have evaluated the influences of these processes on SH. SH often occurs in grassland grazed by cattle and sheep. Understanding the formation and dynamics of SH is important because SH profoundly affects local and regional ecological processes. We propose a new way to quantify the effect of the local immigration and extinction of species on SH, and try to clarify the influence of the processes on SH
Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions,
2023
Escola Superior Agrária de Castelo Branco, Portugal
Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions, J. P. Carneiro, L. Cardenas, D. Hatch, H. Trindade, J. Hawkins, David Scholefield, D. Chadwick
IGC Proceedings (1997-2023)
In recent decades, a very intensive dairy farming system has been developed in northern Portugal. Considering the appreciable amounts of slurry generated and the small farm areas for spreading, this activity involves large annual inputs of N with the risk of undesirable consequences for the environment. Emission of greenhouse gases from agricultural sources, such as N2O (originating from nitrification and denitrification) and CH4, therefore need to be reduced. The aim of this laboratory experiment was to evaluate the effectiveness of two nitrification inhibitors (dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP)) in reducing nitrification and subsequent denitrification after …
Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland,
2023
AgResearch, New Zealand
Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland, Cesar S. Pinares-Patiño, Y. Rochette, M. Fabre, J.-P. Jouany, C. Martin
IGC Proceedings (1997-2023)
Global warming induced by the human-enhanced concentrations of greenhouse gases (GHG) in the atmosphere is a major environmental concern of our day. Enteric methane (CH4) is the most important GHG associated with grazing livestock. The emissions of methane may be influenced by environmental conditions and grazing management. Stocking rate (SR), the number of animals per unit of land area, remains the simplest management tool in pastoral farming. However, little is known about the influence of SR on CH4 emission. The objective of this study was to compare the CH4 emissions from cattle managed under low and …
Carbon Accumulation Under Brachiaria Pastures In The Brazilian Cerrado In Relation To Their Productivity,
2023
EMBRAPA, Brazil
Carbon Accumulation Under Brachiaria Pastures In The Brazilian Cerrado In Relation To Their Productivity, R. M. Boddey, S. P. Braz, R. S. M. Dos Santos, B. J. R. Alves, S. Urquiaga
IGC Proceedings (1997-2023)
Vast areas of land within Brazil has been converted from either the native vegetation of the Amazon and Atlantic forests or the native vegetation (NV) of the central savanna region (the Cerrado) to Brachiaria spp pastures. Productive pastures (PPs) in these regions eventually accumulate soil carbon (C) in excess of levels under native vegetation. However the effect of pasture degradation on soil C stocks has not been reported. We compared soil C stocks under both NV and Brachiaria pastures varying in productivity according to the indicators of Oliveira et al. (2004) over 5 sites in the Cerrado region.
Comparison Of Methodological Tools In Tropical Soil Carbon Sequestration Field Research,
2023
Wageningen University and Research Centre, The Netherlands
Comparison Of Methodological Tools In Tropical Soil Carbon Sequestration Field Research, Bram Van Putten, M. C. Amézquita
IGC Proceedings (1997-2023)
Models play a crucial role in studying complex systems like soil Carbon sequestration processes (Hanson et al., 2001). A Carbon sequestration research project is currently under way in pasture and silvopastoral systems of four Tropical American ecosystems. A main research question is the identification of Land Management Systems (LMS) that exhibit optimal soil Carbon sequestration capacity (identification question). Another main issue is the extrapolation of data in space and time (extrapolation question).
Effects Of Tropical Legumes With Contrasting Tannin Contents And Mixtures Of Them On In Vitro Ruminal Fermentation And Methanogenesis,
2023
ETH-Zürich, Switzerland
Effects Of Tropical Legumes With Contrasting Tannin Contents And Mixtures Of Them On In Vitro Ruminal Fermentation And Methanogenesis, H. D. Hess, F. L. Valencia, P. Avila, C. E. Lascano, Michael Kreuzer
IGC Proceedings (1997-2023)
Previous in vitro experiments have showed that the supplementation of a low-quality grass diet with Arachis pintoi or Cratylia argentea (legumes low in tannins) enhanced ruminal fermentation and methane release, whereas the supplementation with Calliandra calothyrsus (rich in tannins) decreased methane release and suppressed organic matter (OM) degradation and N turnover (Hess et al., 2003). It was hypothesised that a mixture of tanniniferous legumes with legumes free of or low in tannins would result in a methane-suppressing effect but without impairing ruminal nutrient degradation.
A Simulation Study Of Nitrous Oxide Emissions From A Fertilised, Grazed Grassland Site In Ireland,
2023
University College Dublin, Ireland
A Simulation Study Of Nitrous Oxide Emissions From A Fertilised, Grazed Grassland Site In Ireland, Michael J. Hawkins, J. Connolly, B. Hyde, M. Ryan, R. P. O. Schulte
IGC Proceedings (1997-2023)
Nitrous oxide (N2O) emissions from grazed grassland are understood to be strongly influenced by the availability of a mineral N source, soil temperature and soil water content (Skiba & Smith, 2000). We derive an empirical model of emissions based on these factors and use it to simulate daily emissions from a fertilised, grazed grassland site in Wexford, Ireland, under different application schedules and climatic conditions for the period 1994 to 2001, inclusive (Table 1).
Cattle Overwintering Areas In Middle-European Conditions - Important “Point” Sources Of Nitrous Oxide Emissions,
2023
Academy of Sciences of the Czech Republic, Czech Republic
Cattle Overwintering Areas In Middle-European Conditions - Important “Point” Sources Of Nitrous Oxide Emissions, M. Šimek, J. Hynšt, P. Brůček, J. Čuhel, D. Elhottová, H. Šantrůčková, V. Kamír
IGC Proceedings (1997-2023)
Nitrous oxide (N2O) emissions in grazed grasslands are strongly influenced by animal excreta (Fowler et al., 1997). In addition, soil compaction caused by animal traffic significantly influences soil physical conditions and thus directly or indirectly impacts on the microbial processes producing N2O. In the Czech Republic pastures are mostly located in hilly and mountain areas. During the growing season, cattle are typically grazing, while during the winter the animals are concentrated near the animal house on a relatively small plot called an "overwintering area". The objective of this study was to estimate the fluxes of …
Modelling Nitrous Oxide Emissions From Grazed Grasslands In New Zealand,
2023
Landcare Research, New Zealand
Modelling Nitrous Oxide Emissions From Grazed Grasslands In New Zealand, Surinder Saggar, D. L. Giltrap, C. Li, Carolyn B. Hedley, K. R. Tate, S. Lambie
IGC Proceedings (1997-2023)
Spatial and temporal variability are major difficulties when quantifying annual N2O fluxes at the field scale. New Zealand currently relies on the IPCC default methodology (National Inventory Report, 2004). This methodology is too simplistic and generalised as it ignores all site-specific controls, but is also not sufficiently flexible to allow mitigation options to be assessed. Therefore, a more robust, process-based approach is required to quantify N2O emissions more accurately at the field level. Denitrification-decomposition (DNDC) is a process-based model originally developed (Li et al., 1992) to quantify agricultural nitrous oxide (N2O) emissions across …
Modelling Effects Of Agricultural Policies On Regional Greenhouse Gas Emissions From Cattle Raising Production Systems In Baden-Württemberg (Southwest Germany),
2023
Institute for Energy and Environment, Germany
Modelling Effects Of Agricultural Policies On Regional Greenhouse Gas Emissions From Cattle Raising Production Systems In Baden-Württemberg (Southwest Germany), Henry Neufeldt, M. Schäfer, E. Angendt, M. Kaltschmitt, J. Zeddies
IGC Proceedings (1997-2023)
In the light of the anthropogenic climate change and the resulting need to mitigate greenhouse gas (GHG) emissions, policies are needed which efficiently abate GHG emissions in the agricultural sector. However, reliable estimates of regional GHG abatement potentials in the agricultural sector are rare because the models do not integrate the economic and environmental effects of different agricultural policies and are generally restricted to a single-gas approach. Coupling an economic sector model with a process-oriented ecosystem model can overcome this gap and thus provide realistic exante information of socioeconomically and environmentally sustainable agricultural policies.
Nitrogen Fluxes In Grassland In Response To Inter-Annual Climate Variability,
2023
Agroscope FAL Reckenholz, Switzerland
Nitrogen Fluxes In Grassland In Response To Inter-Annual Climate Variability, Pierluigi L. Calanca, Juerg Fuhrer
IGC Proceedings (1997-2023)
Most model studies dealing with the response of grassland dynamics to climate change (e.g. Thornley & Cannell, 1997; Riedo et al., 2000) consider either step changes or a smooth transition in the climatic drivers, therefore neglecting short-term variations. However, the inter-annual variability of the climatic and edaphic elements (Calanca, 2004) can be substantial, with important consequences for the fluxes of nitrogen (N). The objective of this study is to investigate the response of nitrogen fluxes to this type of variability with the help of the Pasture Simulation Model (PaSim), looking at years considerably differing in terms of temperature, radiation …
Potential Climate Change Impacts On Beef Production Systems In Australia,
2023
Department of Primary Industries and Fisheries, Australia
Potential Climate Change Impacts On Beef Production Systems In Australia, David H. Cobon, K. L. Bell, G. M. Mckeon, J. F. Clewett, S. Crimp
IGC Proceedings (1997-2023)
There is increasing evidence suggesting that Australia's climate is changing due to enhanced levels of greenhouse gases and that it will continue to change (Pittock 2003). Climate changes are partly established, however the impact on systems, industries and process are unclear. Industry distribution reflects climatically imposed boundaries and the relative profitability of alternative land use. Climate change may negatively impact some existing industries but create opportunities for others. This study provides an assessment of the likely impacts of plausible climate change on the beef industry in central Queensland.
Targeted Seasonal Climate Forecasts Offer More To Pastoralists,
2023
Department of Primary Industries and Fisheries, Australia
Targeted Seasonal Climate Forecasts Offer More To Pastoralists, David H. Cobon, J. N. Park, K. L. Bell, I. W. Watson, W. Fletcher, M. Young
IGC Proceedings (1997-2023)
The existing forecast systems such as the Southern Oscillation Index (SOI) phase system (Stone et al., 1996) and the Sea Surface Temperature (SST) phase system (Drosdowsky 2002) produce rolling three monthly forecasts with lead-times of either zero (SOI phase) or 1 month (SST phase). Both forecasts are reissued monthly. This approach leaves little time for pastoralists to consider the forecast and then make changes to management decisions. In addition the forecast period can often be of little interest because of the seasonal pattern of rainfall.
Yield Progress Of Perennial Ryegrass And Silage Maize - Genetic Gain Or Climate Change?,
2023
Christian-Albrechts-University of Kiel, Germany
Yield Progress Of Perennial Ryegrass And Silage Maize - Genetic Gain Or Climate Change?, Antje Herrmann, A. Kornher, Friedhelm Taube
IGC Proceedings (1997-2023)
Gains in annual dry matter yield (DMY) from breeding achieved during the last decades are reported to range between 2.5 and 6% per decade for perennial ryegrass (Wilkins & Humphreys, 2003). In contrast, accelerated progress in improving DMY has been achieved for silage maize, varying between 8 and 13% per decade (Lauer et al., 2001). These gains are mainly attributed to (i) genetic yield potential increase, (ii) improved crop management and (iii) increased stress tolerance. The potential impact of climate change on yield progress, however, is disregarded in most studies. The objective of this study therefore was to quantify …
Shifts In N-Efficiency Of Different Farm Types In Response To Climate Change,
2023
Agroscope FAL Reckenholz, Switzerland
Shifts In N-Efficiency Of Different Farm Types In Response To Climate Change, S. Dueri, P. L. Calanca, Juerg Fuhrer
IGC Proceedings (1997-2023)
Climate change may affect European farms, but in contrast to individual crops - the sensitivity of whole farming systems has not been the subject of much research. At the farm level, where different farm units are linked through the availability and flow of nitrogen (N), effects on individual crops are interlinked, and through shifts in grasslands and related animal production with altered nutrient flows. Ideally, N flows into the system and N-export with products should be equal, and thus N-use-efficiency (NUE), expressed as the ratio of N export to N loss, would be maximal. The objective of this study was …
The Effect Of Extremes In Soil Moisture Content On Perennial Ryegrass Growth,
2023
Department of Agriculture and Rural Development, UK
The Effect Of Extremes In Soil Moisture Content On Perennial Ryegrass Growth, A. Scott Laidlaw
IGC Proceedings (1997-2023)
Seasonal distribution of rainfall in the UK and Ireland is predicted to become more variable (Sweeney, 2003). The problems of excessive soil moisture on grass utilisation and the effect of deficit in soil moisture on grass growth are well known. However the effect of excess rainfall on the growth of sown grass is less clear and is usually not taken into account in grass growth models. This study was carried out to investigate the potential impact of excess moisture on perennial ryegrass growth in the field and to investigate the relative effect of soil moisture varying from deficit to excess …
Forage Grass Phenology In Relation To Climate Change,
2023
Plant Breeding and Acclimatisation Institute, Poland
Forage Grass Phenology In Relation To Climate Change, G. Żurek
IGC Proceedings (1997-2023)
Phenological phases of plants, such as heading or flowering are mainly driven by environmental factors such as pests, diseases, competition, soil properties, genetics, age and, most importantly, weather conditions (Menzel & Fabian, 1999; Menzel 2000). At the end of the last century there was an emerging recognition that phenological records can be especially useful in environmental monitoring and it has gained the UK government approval as an indicator of climate change (Sparks et al., 2000). The aim of this work was to analyse long-term trends in the mean heading date for Polish ecotypes of three forage grass species.
Long-Term Responses Of A Mesic Grassland To Manipulation Of Rainfall Quantity And Pattern,
2023
Colorado State University
Long-Term Responses Of A Mesic Grassland To Manipulation Of Rainfall Quantity And Pattern, A. K. Knapp, J M. Blair, P. A. Fay, M. D. Smith, S. L. Collins, J. M. Briggs
IGC Proceedings (1997-2023)
Climatic variability is an inherent feature of grassland biomes, with large fluctuations in temperatures combined with precipitation regimes characterised by floods and severe drought occurring on both an interannual and seasonal scale. Global climate models and emerging data indicate that extremes in precipitation regimes are increasing worldwide coupled with increases in temperature. Thus, variability in spatial and temporal patterns of water availability in grasslands, as directly influenced by altered precipitation patterns and indirectly by increased temperatures, will likely increase in the future. The objectives of our experiments were to experimentally manipulate rainfall amount and temporal patterns (amount and timing of …
Dynamics Of Long-Term Carbon Sequestration On Rangelands In The Western Usa,
2023
U.S. Department of Agriculture
Dynamics Of Long-Term Carbon Sequestration On Rangelands In The Western Usa, G. E. Schuman, L. J. Ingram, P. D. Stahl, G. F. Vance
IGC Proceedings (1997-2023)
Rangelands in the USA occupy 161 million hectares of land. Worldwide, rangelands occupy about half of the land area and account for more than 1/3 of the world's terrestrial carbon (C) reserves. Because of their large land area, rangelands have the potential to sequester a significant amount of additional atmospheric C. Schuman et al. (2001) estimate that rangelands and marginal croplands restored to grasslands in the USA can sequester 64 million metric tonnes C/ha/yr if properly managed. The objective of this research was to evaluate the long-term effects of grazing on soil C storage in a northern mixed-grass prairie (NMP).
