Feasibility assessment of Japan's fertilizer reduction target: A meta-analysis and its implications for nitrogen waste.

Reducing synthetic nitrogen fertilizer (SNF) use is critical for mitigating environmental nitrogen (N) pollution caused by excessive reactive nitrogen and lowering the cost of chemical N fertilizer inputs in agricultural management. In response, Japan has set a national target to reduce chemical fertilizer inputs, with a goal of 30% reduction in SNF use. To assess the feasibility of this target, we collected ca.

Biochar Impacts on Crop Productivity and Greenhouse Gas Emissions from an Andosol.

To assess the impacts of biochar application on crop productivity and global warming mitigation, a 4-yr field experiment was conducted in a well-drained Andosol in northern Japan. Wood residue-derived biochar (pyrolyzed at >800°C) was applied at rates of 0, 10, 20, and 40 Mg ha for potatoes, winter wheat, sugar beet, and soybeans cultivated in rotation, and CO, NO, and CH emissions from the soil and yield and quality of the harvested materials were measured. Biochar application, regardless of rate, had no significant impact on yield and quality of the harvested materials, except for soybean grain yield.

Assessing energy efficiencies and greenhouse gas emissions under bioethanol-oriented paddy rice production in northern Japan.

To establish energetically and environmentally viable paddy rice-based bioethanol production systems in northern Japan, it is important to implement appropriately selected agronomic practice options during the rice cultivation step. In this context, effects of rice variety (conventional vs. high-yielding) and rice straw management (return to vs.

Use of a microchip electrophoresis system for estimation of bacterial phylogeny and analysis of NO3- reducing bacterial flora in field soils.

Phylogenetic estimation method without determination of DNA sequence was developed. By this method, fragment length polymorphism separately digested with multiple restriction enzymes was measured using microchip electrophoresis and affiliated with those calculated from corresponding DNA sequence in the theoretical database. The phylogenies of 129 NO(3)(-) reducing bacteria newly isolated from field soils were estimated by this method, and were compared to those by carbon source utilization profiles and by comparative sequence analysis of 16S rDNA.