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To contribute to national greenhouse gas emissions (GHG) reduction targets, grain growers need strategies that minimise emissions associated with grain production. We used life cycle assessments (LCAs) with field-measured production inputs, grain yields and proteins, legume nitrogen ([N.sub.2]) fixation, and soil nitrous oxide ([N.sub.2]0) and methane (C[H.sub.4]) emissions, to explore mitigation strategies in 3-year crop sequences in subtropical Australia. The sequences were: canola plus 80 kg/ha fertiliser nitrogen (80N)-wheat 85N-barley 65N ([Ca.sub.N][Wt.sub.N][Ba.sub.N]), chickpea ON-wheat 85N-barley 5N ([Cp.sub.N][Wt.sub.N]Ba), chickpea ON-wheat 5N-chickpea 5N (CpWtCp), and chickpea ON-sorghum 45N (CpSgN). We also assessed the impacts of split fertiliser N application and urea coated with DMPP, a nitrification inhibitor, on the LCA for the [Ca.sub.N][Wt.sub.N][Ba.sub.N] sequence.Total pre-farm plus on-farm GHG emissions varied between 915 C[O.sub.2]-e/ha (CpSgN) and 1890 C[O.sub.2]-e/ha ([Ca.sub.N][Wt.sub.N][Ba.sub.N]). Cumulative [N.sub.2]O emitted over the 3-year study varied between 0.479 kg [N.sub.2]O-N/ha (CpWtCp) and 1.400 kg [N.sub.2]O-N/ha ([Ca.sub.N][Wt.sub.N][Ba.sub.N]), which constituted 24 44% of total GHG emissions. Fertiliser production accounted for 20% (CpSgN) to 30% ([Ca.sub.N][Wt.sub.N][Ba.sub.N]) of total emissions. An extra 4.7 kg C[O.sub.2]-e/ha was emitted for each additional kg N/ha of applied N fertiliser. Three-year CH4 emissions ranged from -1.04 to -0.98 kg CH4-C/ha. Split N and DMPP strategies could reduce total GHG emissions of [Ca.sub.N][Wt.sub.N][Ba.sub.N] by 17 and 28% respectively. Results of the study indicate considerable scope for reducing the carbon footprint of subtropical, dryland grains cropping in Australia.Additional keywords: carbon dioxide, carbon footprint, fertiliser N, grain cropping, greenhouse gas emissions, life cycle assessment, methane, nitrous oxide., IntroductionQuantification of anthropogenic greenhouse gas (GHG) emissions from agriculture, specifically nitrous oxide ([N.sub.2]O), methane (C[H.sub.4]), and carbon dioxide (C[O.sub.2]), at scales from national inventories to individual fields reflects concern about [...]

The authors constructed the framework for a preliminary assessment of climate change impact on the rice insurance payout in Japan. The framework consisted of various models ranging from climate projection downscaling, rice yield estimation, yield loss assessment, and rice insurance payout estimation. In this study, a simulation was conducted based on the dynamically downscaled regional climate projection with a lateral boundary condition given by the global climate projection of the Meteorological Research Institute Coupled General Circulation Model, version 2 (MRI CGCM2), under the A2 scenario of the Special Report on Emission Scenarios (SRES). Results indicated that rice yield in the 2070s will decrease slightly in central and western Japan and increase in northern Japan. The increase in yield was derived from a significant reduction in yield loss caused by cool-summer damage; on the other hand, the decrease in yield was caused by the increase in yield loss caused by heat stress and the shortening of the growth period induced by the temperature rise. The increase in the atmospheric C[O.sub.2] concentration resulted in an increase in paddy rice biomass because of the fertilization effect; however, the increase in biomass was not enhanced much as a result of shortening of the growth period if early planting was not considered as an adaptation practice. Reflecting such changes in yield, the rice insurance payout significantly decreased in northern Japan but only slightly increased in the areas of central and western Japan. In total, the 9-yr mean payout in Japan in the 2070s decreased to 120.2 billion yen; the value corresponded to 87% of the payout averaged over 9 yr in the 1990s (1991-99).

Rice (Oryza sativa L.), the main staple food in Asia, is typically produced on submerged anaerobic soils, which generally have slower decomposition of soil organic matter (SOM) than aerobic soils. We sampled four long-term experiments in the Philippines, with two or three rice crops grown each year with continuous or near-continuous soil submergence, to determine the effect of fertilizer management on long-term changes in soil C and N and on C and N balances. Soils were an Aquandic Epiaquoll, an Entic Pellustert, and a Typic Pelludert; soil pH ranged from 5.9 m 6.7. After 17 to 21 yr of continuous rice cultivation, the concentration of total soil organic C (SOC) and total soil N ([N.sub.T]) in the topsoil (0-20 cm) were greater with N-P-K fertilization than without fertilization. During 15 yr of additional continuous rice cropping, topsoil SOC and [N.sub.T] were consistently maintained or increased regardless of N-P-K fertilizer regime. Topsoil SOC increased up to 10% in an experiment with three rice crops per year and removal of all aboveground plant biomass after each crop. Subsoil SOC and [N.sub.T] (20-80 cm) were not affected by fertilization. The N balances indicated that biological [N.sub.2] fixation averaged 19 to 44 kg N [ha.sub.-1] [crop.sub.-1] across the four experiments. Anaerobic N mineralization (ANM) in the topsoil was maintained during 15 yr of continuous rice cropping with N-P-K fertilization in all four experiments. The results suggest that continuous cultivation of irrigated rice with balanced fertilization on submerged soils maintained or slightly increased SOM and maintained soil N-supplying capacity. Abbreviations: ANM, anaerobic N mineralization; BIARC, Bicol Integrated Agricultural Research Center; BNE biological dinitrogen fixation; LTCCE, long-term continuous cropping experiment; LTFE, long-term fertility experiment; [N.sub.T] total soil nitrogen; PhilRice, Philippine Rice Research Institute; POC, permanganate-oxidizable carbon; SOC, soil organic carbon; SOM, soil organic matter.

Soil organic C (SOC) pools under long-term management practices provide information on C sequestration pathways, soil quality maintenance, and crop productivity. Farmyard manure (FYM), paddy straw (PS), and green manure (GM) along with inorganic fertilizers were used in a 19-yr-old rice (Oryza sativa L.)--wheat (Triticum aestivum L.) cropping system in subtropical India to evaluate their impact on SOC stock, its different pools--total organic C ([C.sub.tot]); oxidizable organic C ([C.sub.oc]) and its four fractions of very labile ([C.sub.frac1]), labile ([C.sub.frac2]), less labile ([C.sub.frac3]), and nonlabile C ([C.sub.frac4]); microbial biomass C ([C.sub.mic]); and mineralizable C ([C.sub.min]). Cropping with only N-P-K fertilization just maintained SOC content, while N-P-K plus organics increased SOC by 24.3% over the control, their relative efficacy being FYM > PS > GM. A minimum of 3.56 Mg C ha-1 yr-1 was required to be added as organic amendmes to compensate for SOC loss from cropping. The passive ([C.sub.frac3]+[C.sub.frac4]) and [C.sub.min] constituted about 39 and 11.5%, respectively, of [C.sub.tot]. Organics contributed toward the passive pool in the order FYM > PS > GM. Most of the pools were significantly (P = 0.005) correlated with each other. Yield and sustainable yield index were strongly related with [C.sub.frac1], [C.sub.oc], [C.sub.mic], and [C.sub.min]. Results suggest [C.sub.frac1] as a useful indicator for assessing soil health, and balanced fertilization with FYM as suitable management for sustaining crop productivity of the rice--wheat system. Abbreviations: BSR, basal soil respiration; [C.sub.frac1], very labile carbon; [C.sub.frac2], labile carbon; [C.sub.frac3], less labile carbon; [C.sub.frac4], nonlabile carbon; [C.sub.mic], microbial biomass carbon; [C.sub.min], mineralizable carbon; [C.sub.oc], oxidizable organic carbon; [C.sub.tot], total organic carbon; FYM, farmyard manure; GM, green manure; MQ, microbial quotient; PS, paddy straw; qC[O.sub.2], respiratory quotient; SOC, soil organic carbon; SYI, sustainable yield index.

Nutrient flows related to agricultural development in the Baltic States and Sweden after 1988 and the change from collective farms to a market economy with family farms are discussed. Changes in nitrogen and phosphorus flows in agriculture and into the Baltic Sea after independence from Russia came to the Baltic States are compared to changes in Sweden in the same time period.