Forests play a critical role in mitigating climate change because of their high carbon storage and productivity. China has experienced a pronounced increase in forest area resulting from afforestation and reforestation activities since the 1970s. However, few comprehensive analyses have been made to assess the recent dynamics of biomass carbon sinks in China's forests. This study refined biomass carbon sinks of China's forests based on eight forest inventories from 1973 to 2013. These sinks increased from 25.0 to 166.5 Tg C yr?1 between 1973 and 2008, and then decreased to 130.9 Tg C yr?1 for the period of 2009–2013 because the increases in forest area and biomass carbon density became slower. About 7% and 93% of this sink reduction occurred in planted and natural forests. The carbon sinks for young, middle-aged and premature forests decreased by 27.3, 27.0, and 7.6 Tg C yr?1, respectively. 42% of this decrease was offset by mature and overmature forests. During 2009–2013, forest biomass carbon sinks decreased in all regions but the north and northwest regions. The drivers for changes of forest biomass sinks differ spatially. More intensive harvest of young and middle-aged forests and snow damage were the major drivers for the decreases of biomass carbon sinks in the east (8.0 Tg C yr?1) and south (19.8 Tg C yr?1) regions. The carbon sink reduction in the southwest region (16.7 Tg C yr?1) was mainly caused by increased timber harvesting and natural disturbances, such as droughts in Yunnan province, snow damage in Guizhou province and forest fires in Sichuan province. In the northeast region, the sink reduction occurred mainly in Heilongjiang province (7.9 Tg C yr?1) and was caused dominantly by the combined effects of diseases, windthrow and droughts. The carbon sink increase was primarily attributed to forest growth and decreased deforestation in the north (10.0 Tg C yr?1) and northwest (2.3 Tg C yr?1) regions.
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机译:森林因其高碳储量和高生产力而在缓解气候变化中起着关键作用。自1970年代以来,由于造林和再造林活动,中国的森林面积显着增加。但是,很少有全面的分析来评估中国森林中生物质碳汇的近期动态。这项研究基于1973年至2013年的8个森林资源清单,对中国森林的生物质碳汇进行了提炼。这些汇在1973年至2008年间从25.0 Tg C yr?1增加到166.5 Tg C yr?1,然后在2008年降低到130.9 Tg C yr?1。 2009-2013年,因为森林面积和生物量碳密度的增长变慢。减少的水槽中约有7%和93%发生在人工林和天然林中。年轻人,中年和过早森林的碳汇分别减少了27.3、27.0和7.6 Tg C yr?1。 42%的下降被成熟和过早的森林所抵消。在2009–2013年期间,除北部和西北部地区外,所有地区的森林生物量碳汇均下降。森林生物量汇变化的驱动因素在空间上有所不同。东部地区(8.0 Tg C yr?1)和南部地区(19.8 Tg C yr?1)的生物量碳汇减少的主要原因是年轻和中年森林的更密集采伐和雪灾。西南地区碳汇减少(16.7 Tg C yr?1)主要是由于木材采伐增加和自然干扰,例如云南省干旱,贵州省雪灾和四川省森林大火。在东北地区,汇的减少主要发生在黑龙江省(7.9 Tg C yr?1),主要是由疾病,刮风和干旱的共同作用引起的。碳汇增加主要归因于北部(10.0 Tg Cyryr-1)和西北(2.3 Tg Cyryr1)地区的森林生长和森林砍伐的减少。
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机译:分离的核酸(多核苷酸),反义寡核苷酸,抑制或减少编码CO2SEN蛋白的消息和/或CO2SEN蛋白或植物多聚核苷酸和多肽多糖的植物植株的表达的方法植物保护细胞,植物细胞,植物片,植物组织或植物,植物的一部分的碳吸收量和碳排量的负,正调节及增加,碳保护层和水流以及CO 2 / CO 2交换水交换或损失水开放植物,关闭植物的气孔,部分植物,器官,植物片或植物细胞,以增强或优化植物,植物片,器官,植物,植物的一部分上的生物量积累,植物,种子或植物细胞中的植物细胞或种子,板温度的降低和蒸腾强度的提高,降低了T型保护细胞中的效率降低和碳含量