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The article offers information on an agreement on mutual legal assistance in criminal matters, signed between Japan and the Hong Kong Special Administrative Region of China. It states that the agreement is the fourth bilateral agreement, concluded by Japan. It mentions that the agreement comprises of 20 articles and the preamble, including each party to provide widest mutual legal assistance, and they shall designate their Central Authority.

To evaluate the effect of cultivation, nitrogen fertilizer, and set aside on CH4 uptake after drained marshland was converted into agricultural fields, CH4 fluxes and CH4 concentrations in soil gas werein situmeasured in a drained marsh soil, a set-aside cultivated soil, and cultivated soils in Sanjiang Plain of Northeast China in August 2001. Over the measuring period, the highest CH4 uptake rate was 120.7±6.2 μg CH4 m−2 h−1 in the drained marsh soil and the lowest was 29.5±4.9 μg CH4 m−2 h−1 in the set-aside cultivated soil, showing that there was no significant recovery of CH4 uptake ability 5 years after cultivation activity was stopped. CH4 uptake rates were significantly less in the cultivated soils than in the drained marsh soil by 30.1–74.6%, which resulted mainly from cultivation and partly from nitrogen addition. A significantly negative correlation between CH4 flux and bulk density in the cultivated soils tilled by machine suggests that cultivation reduced CH4 uptake through compaction, because of the enhanced diffusion resistance for CH4 and O2. Nitrogen fertilization slowly reduced but persistently affected CH4 uptake even after long-term application of nitrogen. [ABSTRACT FROM AUTHOR]

Focuses on methane emissions from rice paddies managed by farm practices in Hunan, China. Incorporation of chinese milk vetch and organic manure produced in the winter; Removal of early and late-rice straws; Effect of precipitation in winter on methane emissions during the rice growing period; Information on priming effect of green manure; Estimation of methane emissions based on the methane flux measurements.

To understand the mechanism of diel variation pattern of CH4 emission from the freshwater marsh, we measured CH4 emission as well as temperature, redox potential and CH4 concentration in porewater in situ in Sanjiang plain, northeast China. There was an apparent diel variation in CH4 emission with the peak at 9:00 and the lowest at 0:00. However, the difference between the highest and lowest emissions was much smaller in the Deyeuxia angustifolia site than in the Carex lasiocarpa site. In the D. angustifolia site with 3 cm standing water, the diel CH4 emission varied from 6.7 to 8.2 mg CH4 m−2 h−1 since plants only mediated 29% of CH4 emission and CH4 flux increased by merely 8% after plants were covered with a black cloth. In contrast, in the C. lasiocarpa site with 16 cm standing water where plants released 81% of CH4 emission and CH4 flux enhanced by 19% after plants were covered, the diel CH4 emission ranged from 19.5 to 29.7 mg CH4 m−2 h−1. At this site CH4 emission was significantly correlated to mean CH4 concentration in porewater and the latter was related to redox potential. The diel pattern could be explained by change in CH4 oxidation driven by plant photosynthesis. Oxygen generated by plant photosynthesis in the rhizome or rhizosphere and temperature in the vertical profile gradually incremented and reached the peak with a lag time after sunrise. CH4 emission and concentration in porewater increased with temperature when CH4 oxidation was no larger than CH4 production and attained the peak at 9:00 but then decreased when CH4 oxidation was larger than CH4 production. Although less fresh oxygen was transported into the rhizome or rhizosphere after sunset, CH4 oxidation was still driven by oxygen inputted at daytime. When the decreasing CH4 oxidation was again equal to CH4 production, CH4 emission and concentration reached the lowest at midnight and then increased. [Copyright &y& Elsevier]

To understand the mechanism for and effect of standing water depth on CH4 emissions from freshwater marshes, we measured CH4 emissions as well as labile organic C (LOC) and CH4 concentration in porewater in situ in Sanjiang Plain of Northeast China. Average fluxes of CH4 emissions from Carex lasiocarpa, Carex meyeriana and Deyeuxia angustifolia marshes were 35.6, 31.1 and 25.7 mg CH4 m−2 h−1, respectively, during the 3-day measuring period in August 2001, increased as standing water depth incremented from 5 to 20 cm. Standing water depth determined the type of marsh plants, which governed CH4 transport, and the amount of plant litters, which resulted in the difference in LOC for methanogenesis among marshes. LOC greatly affected CH4 concentration and total amount of CH4 in porewater, whereas the latter was significantly related with CH4 emissions. The more aboveground plant biomass especially stem density accelerated CH4 emission but was of less importance compared with the standing water among marshes. [Copyright &y& Elsevier]

The ongoing development of the Global Carbon Project (GCP) global methane (CH 4 ) budget shows a continuation of increasing CH 4 emissions and CH 4 accumulation in the atmosphere during 2000-2017. Here, we decompose the global budget into 19 regions (18 land and 1 oceanic) and five key source sectors to spatially attribute the observed global trends. A comparison of top-down (TD) (atmospheric and transport model-based) and bottom-up (BU) (inventory- and process model-based) CH 4 emission estimates demonstrates robust temporal trends with CH 4 emissions increasing in 16 of the 19 regions. Five regions-China, Southeast Asia, USA, South Asia, and Brazil-account for >40% of the global total emissions (their anthropogenic and natural sources together totaling >270 Tg CH 4  yr -1 in 2008-2017). Two of these regions, China and South Asia, emit predominantly anthropogenic emissions (>75%) and together emit more than 25% of global anthropogenic emissions. China and the Middle East show the largest increases in total emission rates over the 2000 to 2017 period with regional emissions increasing by >20%. In contrast, Europe and Korea and Japan show a steady decline in CH 4 emission rates, with total emissions decreasing by ~10% between 2000 and 2017. Coal mining, waste (predominantly solid waste disposal) and livestock (especially enteric fermentation) are dominant drivers of observed emissions increases while declines appear driven by a combination of waste and fossil emission reductions. As such, together these sectors present the greatest risks of further increasing the atmospheric CH 4 burden and the greatest opportunities for greenhouse gas abatement., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)