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Global climatic changes: modelling the potential responses of agro-ecosystems with special reference to crop protection.
1995
Goudriaan J. | Zadoks J.C.
The potential role of temperate forests as sinks for CO(2): examples from the German environmental policy against global warming.
1992
Gregor H.D.
Regional differences in plant levels and investigations on the phytotoxicity of lithium
2016
Franzaring, Jürgen | Schlosser, Sonja | Damsohn, Walter | Fangmeier, Andreas
The growing use of lithium (Li) in industrial and energetic applications and the inability to completely recycle the alkali metal will most likely increase anthropogenic emissions and environmental concentrations in the future. Although non-essential to plants, Li+ is an important ultra-trace element in the animal and human diet and is also used in the treatment of e.g. mental disorders. Most of the lithium is consumed with the drinking water and vegetables, but concentrations in foodstuffs vary with the geochemistry of the element. In order to identify potential risks and to avoid an overmedication due to consumption of Li rich or Li contaminated foods it is advisable to identify background levels and to derive recommended Daily Allowances (RDAs) for the element. Although Germany does not possess large amounts of primary or secondary resources of lithium, geochemical investigations (mineral and ground waters and soils) in this country confirm a wide variation of environmental concentrations with generally higher levels in the southwest. Despite the large number of soil and water data, only very few data exist on lithium concentrations in plants and its phytotoxicity. Within the scope of present study common grassland plant species were sampled in regions of SW-Germany with reportedly high geogenic levels of Li. The data are discussed with regard to literature surveys and existing reference values. Since lithium has phytotoxic effects a greenhouse experiment was performed with different Li salts (LiCl and Li2CO3) and plant species (maize, bean and buckwheat) to derive dose-response relationships for the endpoint shoot growth. While corn growth was not reduced significantly by soil concentrations of 118 ppm, EC50 values in buckwheat were 47 and 16 ppm for lithium derived from LiCl and Li2CO3, respectively.
Mostrar más [+] Menos [-]Greenhouse gas emissions from a wheat–maize double cropping system with different nitrogen fertilization regimes
2013
Hu, Xiao-Kang | Su, Fang | Ju, Xiao-Tang | Gao, Bing | Oenema, O. (Oene) | Christie, Peter | Huang, Bin-Xiang | Jiang, Rong-Feng | Zhang, Fu-Suo
Here, we report on a two-years field experiment aimed at the quantification of the emissions of nitrous oxide (N2O) and methane (CH4) from the dominant wheat–maize double cropping system in North China Plain. The experiment had 6 different fertilization strategies, including a control treatment, recommended fertilization, with and without straw and manure applications, and nitrification inhibitor and slow release urea. Application of N fertilizer slightly decreased CH4 uptake by soil. Direct N2O emissions derived from recommended urea application was 0.39% of the annual urea-N input. Both straw and manure had relatively low N2O emissions factors. Slow release urea had a relatively high emission factor. Addition of nitrification inhibitor reduced N2O emission by 55%. We conclude that use of nitrification inhibitors is a promising strategy for N2O mitigation for the intensive wheat–maize double cropping systems.
Mostrar más [+] Menos [-]Carbon storage and sequestration by trees in urban and community areas of the United States
2013
Nowak, David J. | Greenfield, Eric J. | Hoehn, Robert E. | Lapoint, Elizabeth
Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m−2 of tree cover and sequestration densities average 0.28 kg C m−2 of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes).
Mostrar más [+] Menos [-]CO₂ emissions from farm inputs “Case study of wheat production in Canterbury, New Zealand”
2012
Safa, Majeed | Samarasinghe, Sandhya
This review paper concentrates on carbon dioxide emissions, discussing its agricultural sources and the possibilities for minimizing emissions from these sources in wheat production in Canterbury, New Zealand. This study was conducted over 35,300 ha of irrigated and dryland wheat fields in Canterbury. Total CO₂ emissions were 1032 kg CO₂/ha in wheat production. Around 52% of the total CO₂ emissions were released from fertilizer use and around 20% were released from fuel used in wheat production. Nitrogen fertilizers were responsible for 48% (499 kg CO₂/ha) of CO₂ emissions. The link between nitrogen consumption, CO₂ emissions and crop production showed that reducing the CO₂ emissions would decrease crop production and net financial benefits to farmers.
Mostrar más [+] Menos [-]Biomass fuel burning and its implications: Deforestation and greenhouse gases emissions in Pakistan
2010
Tahir, S.N.A. | Rafique, M. | Alaamer, A.S.
Pakistan is facing problem of deforestation. Pakistan lost 14.7% of its forest habitat between 1990 and 2005 interval. This paper assesses the present forest wood consumption rate by 6000 brick kilns established in the country and its implications in terms of deforestation and emission of greenhouse gases. Information regarding consumption of forest wood by the brick kilns was collected during a manual survey of 180 brick kiln units conducted in eighteen provincial divisions of country. Considering annual emission contributions of three primary GHGs i.e., CO2, CH4 and N2O, due to burning of forest wood in brick kiln units in Pakistan and using IPCC recommended GWP indices, the combined CO2-equivalent has been estimated to be 533019 t y-1.
Mostrar más [+] Menos [-]Crops' responses to ozone in Mediterranean environments
2009
Fagnano, Massimo | Maggio, Albino | Fumagalli, Ivano
The Mediterranean environment, and most of the Italian peninsula, presents some peculiarities in terms of crop response to O3 since most physiological mechanisms activated upon O3 exposure, such as stomatal closure, often overlap and interact with those that underlie plant adaptation to drought and hyperosmotic stress, which are typical of these environments. OTC and EDU experiments have demonstrated that O3 causes strong yield losses when crops are grown without water limitations. However, exposure to water or saline stress significantly reduced O3 effects on crop yield. In this review, we present the methodological approaches that have been used to study plant-ozone interactions in Italy as well as biochemical, physiological and agronomic responses for representative cropping systems of the Mediterranean climate. Is the 22% yield loss due to ambient ozone in non-limiting water conditions a realistic estimate for moderately stressed crops, typical of most Mediterranean regions?
Mostrar más [+] Menos [-]Assessment of present and future risk to Italian forests and human health: Modelling and mapping
2009
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. AOT40 and SOMO35 are and will be high enough to affect forest and human health all over Italy.
Mostrar más [+] Menos [-]Introducing an integrated climate change perspective in POPs modelling, monitoring and regulation
2009
This paper presents a review on the implications of climate change on the monitoring, modelling and regulation of persistent organic pollutants (POPs). Current research gaps are also identified and discussed. Long-term data sets are essential to identify relationships between climate fluctuations and changes in chemical species distribution. Reconstructing the influence of climatic changes on POPs environmental behaviour is very challenging in some local studies, and some insights can be obtained by the few available dated sediment cores or by studying POPs response to inter-annual climate fluctuations. Knowledge gaps and future projections can be studied by developing and applying various modelling tools, identifying compounds susceptibility to climate change, local and global effects, orienting international policies. Long-term monitoring strategies and modelling exercises taking into account climate change should be considered when devising new regulatory plans in chemicals management. Climate change implications on POPs are addressed here with special attention to monitoring, modelling and regulation issues.
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