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Abstract: Though in last four decades various alternate energy sources have come into the limelight, the hyperbolic use of coal as a prime energy source cannot be counterbalanced. Disposal of high amount of fly-ash from thermal power plants absorbs huge amount of water, energy and land area by ash ponds. In order to meet the growing energy demand, various environmental, economic and social problems associated with the disposal of fly-ash would continue to increase. Therefore, fly-ash management would remain a great concern of the century. Fly-ash has great potentiality in agriculture due to its efficacy in modification of soil health and crop performance. The high concentration of elements (K, Na, Zn, Ca, Mg and Fe) in fly-ash increases the yield of many agricultural crops. But compared to other sectors, the use of fly-ash in agriculture is limited. An exhaustive review of numerous studies of last four decades took place in this paper, which systematically covers the importance, scope and apprehension regarding utilization of fly-ash in agriculture. The authors concluded that though studies have established some solutions to handle the problems of radioactivity and heavy metal content in fly-ash, long-term confirmatory research and demonstration are necessary. This paper also identified some areas, like proper handling of dry ash in plants as well as in fields, ash pond management (i.e., faster decantation, recycling of water, vertical expansion rather than horizontal), monitoring of soil health, crop quality, and fate of fly-ash in time domain, where research thrust is required. Agricultural lime application contributes to global warming as Intergovernmental Panel on Climate Change (IPCC) assumes that all the carbon in agricultural lime is finally released as CO2 to the atmosphere. It is expected that use of fly-ash instead of lime in agriculture can reduce net CO2 emission, thus reduce global warming also. [Copyright &y& Elsevier]

Abstract: Previous studies have shown that temperature rise leads to an earlier onset of spring in wild plant species and that farmers are not keeping track of climate change. Crop growth models and experiments show yield gains to be obtained from earlier sowing. Why do farmers not sow earlier? We propose simple models on the relation between several weather variables and farmers’ sowing dates and test these models with 392 observed weekly sugar beet sowing percentages in the Netherlands. Data showed no correlation between spring temperature and sowing dates. However when we corrected for number of frost days in spring, we clearly saw earlier sowing at higher temperatures. Frost causes crumbling of the soil resulting in a nice seedbed; farmers sow later when there have been less frost days. Temperature rise “makes” farmers sow earlier, but the number or frost days simultaneously decreases and this “makes” farmers sow later. The combined effect is that temperature rise leads to only a small net advance in sowing date, 2 days per 1°C according to our model. Many climate change studies have assumed advances in sowing date are often larger than likely based on historical trends and models developed in this paper. Such studies may well be overly optimistic in projected yield gains that follow from earlier sowing. Our results also revealed that sowing dates were correlated with the sum of solar radiation over the preceding 7–10 months. This correlation remained significant also when other weather variables (rain, temperature, frost days) were accounted for. Our work raises the question what is the process causing this correlation and does such correlation with radiation sum also show up in other time series of phenological events or human behaviour. [Copyright &y& Elsevier]

Abstract: To learn the historical response of cropping system to climate change will benefit the strategy decision of future cropping adaptation. In this paper, we conducted an integrated analysis of the climate records of seventy-two meteorological stations and the records of crop yields over the period 1970–2009 in Northeast China. It was found that over these forty years, the daily mean, maximum and minimum temperatures during crop growing season increased on average by 0.34°C, 0.28°C, 0.43°C every ten years, respectively. No significant change in the precipitation was found, although the differences between years were large. After de-trending the agronomic technique contributions to the increments of crop yields, the historical warming had led to great annually increments of 16.6kgha−1, 15.5kgha−1 and 3.2kgha−1 in rice, corn and soybean yields, respectively. According to the historical warming level, present cropping boundaries can be theoretically extended northward about 80km with a prolonged growing period by 10 days compared to the 1970s. Actually, the growth durations of newly approved varieties of rice, corn and soybean have really prolonged by 14.0 days, 7.0 days and 2.7 days since the 1950s, respectively. The actual growing periods of rice and corn have also respectively prolonged by 6 days and 4 days due to the adjustment of sown and harvest dates by the farmer since 1990s. The existing rice cropping region has been extended northward 80km in the 2006 compared to the 1970. These actual responses were consistent with the theoretical calculation according to the historical warming trends. Our results demonstrate that cropping system owns the potential to progressively and actively adapt to the global warming for high yield through a comprehensive strategy. [Copyright &y& Elsevier]

Abstract: Greenhouse gas (GHG) emissions are expected to cause global warming which results in extreme weather changes that could affect crop yields and productivity, food supplies and food prices. It is also expected that climate change will have an impact on animal metabolism and health, reproduction and productivity. On the other hand, the expected increased demand of animal origin products in the coming years will increase the reared animal numbers and consequently GHG emissions. This paper outlines the main GHGs emitted from livestock which are CO2, CH4 and N2O, coming from respiration, enteric fermentation and manure management respectively, with CH4 and N2O having the highest global warming potential. Ruminant livestock has the highest contribution to these GHG emissions with small ruminants share being 12.25% of the total GHG emissions from livestock''s enteric and manure CH4, and manure N2O in CO2 equivalent, producing 9.45 kg CO2 equivalent per kg body weight with the respective values for cattle, pigs and poultry being 5.45, 3.97 and 3.25. Since the production systems significantly affect the GHG emissions, the grazing, livestock crop complex, and intensive ones account for 30.5%, 67.29% and 5.51% for total CH4 emission (from enteric fermentation and manure management) and 24.32%, 68.11% and 7.57% for N2O respectively. Taking into account the positive and negative impacts of small ruminant livestock production systems to the environmental aspects in general, it is recommended that a number of potentially effective measures should be taken and the appropriate mitigation technologies should be applied in order to reduce effectively and essentially the GHG emissions to the atmosphere, with no adverse effects on intensification and increased productivity of small ruminants production systems. [Copyright &y& Elsevier]