【摘 要】
：
As the source of the Yellow River, Yangtze River, and Lancang River, the Three-River Source Region (TRSR) in China is very important to China’s ecological security. In recent decades, TRSR’s ecosystem has degraded because of climate change and human distu
【机 构】
：
School of Geoscience and Technology, Zhengzhou University, Zhengzhou 450001, China;College of Chemis
论文部分内容阅读
As the source of the Yellow River, Yangtze River, and Lancang River, the Three-River Source Region (TRSR) in China is very important to China’s ecological security. In recent decades, TRSR’s ecosystem has degraded because of climate change and human disturbances. Therefore, a range of ecological projects were initiated by Chinese government around 2000 to curb further degradation. Current research shows that the vegetation of the TRSR has been initially restored over the past two decades, but the respective contri-bution of ecological projects and climate change in vegetation restoration has not been clarified. Here, we used the Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) to assess the spatial-temporal variations in vegetation and ex-plore the impact of climate and human actions on vegetation in TRSR during 2001-2018. The results showed that about 26.02% of the TRSR had a significant increase in EVI over the 18 yr, with an increasing rate of 0.010/10 yr (P ＜ 0.05), and EVI significantly de-creased in only 3.23% of the TRSR. Residual trend analysis indicated vegetation restoration was jointly promoted by climate and hu-man actions, and the promotion of human actions was greater compared with that of climate, with relative contributions of 59.07% and 40.93%, respectively. However, the degradation of vegetation was mainly caused by human actions, with a relative contribution of 71.19%. Partial correlation analysis showed that vegetation was greatly affected by temperature (r = 0.62, P ＜ 0.05) due to the relatively sufficient moisture but lower temperature in TRSR. Furthermore, the establishment of nature reserves and the implementation of the Ecological Protection and Restoration Program (EPRP) improved vegetation, and the first stage EPRP had a better effect on vegetation restoration than the second stage. Our findings identify the driving factors of vegetation change and lay the foundation for subsequent ef-fective management.
其他文献
Main observation and conclusionrnThe reaction of pyridin-2(1H)-ones with PhlCl2 and NH4SCN enables an efficient regioselective thiocyanation,leading to the synthesis of the biologically interesting C5 thiocyanated 2-pyridones in good to high yields.The me
结合区域创新发展需求搭建适合吉林省的创新方法服务体系,整合优势资源,面向不同服务对象设计、实施了多种定制化创新方法服务方案,提升整体创新服务水平.以创新方法工作推进双创结合服务,扩大创新试点示范企业、创新成果集群,示范带动更多创新主体参与创新方法工作,增强创新方法在创新型省份建设中的推进作用.
Main observation and conclusionrnTen new characteristic dihydroagarofuran sesquiterpenoids and three known ones were acquired from the Celastraceae plant Trip-terygium wilfordii.Their structure characterizations were done through spectroscopic data,while
近年来随着科技成果转化政策的出台,科技成果转化体系正在逐步完善.文章通过对宁夏高校及科研院所科技成果转化现状进行分析,梳理存在的问题,并对问题提出对策建议,以期为管理部门提供决策参考.
Main observation and conclusionrnSolvothermal reactions of 3,6-di(pyridin-4-yl)-9H-carbazole (dpc) with Cu(Ⅱ) yielded crystals of two new coordination complexes,namely [Cu(CH3COO)2(dpc)(H2O)2]n·xGuest (1) and [Cu13(HCOO)16(dpc)16(H2O)6](HCOO)10·Guest (2),
工业机理模型库及其开发验证平台针对复杂工业现场中各种监测、判断、求解、优化问题,以及为解决这些问题所需要的数学物理、运营管理、自动控制等算法,建立统一、形式化、可验证的工业机理元模型和元模型驱动的模型库,提供各种机理模型的开发以及相应的数据采集、交换共享、存储调用、管理审计、模型验证功能,从而支持操作手、工程师、管理人员进行智能制造和协同制造的复杂诊断和综合决策.
江淮地区常年稻-麦轮作面积4,500多万亩、占全国的2/3,年产粮4,000万吨以上,长期以来为保障国家口粮安全作出了重要贡献.然而江淮稻、麦传统生产中普遍存在资源利用不充分,季节间分配不合理,灾害频发;周年秸秆机械化还田耕作、播种质量差,生产肥水药投入大等问题,造成丰产增效抗逆难以兼顾,特别是小麦产量低、品质差,诱发冬季弃耕,直接威胁区域粮食生产和农民增收,甚至影响国家口粮安全生产.在国家重点研发计划“粮食丰产增效科技创新”重点专项的支持下,安徽省农业科学院稻麦创新团队结合安徽粮食多元种植制度与特点,针
海洋强国已成为国家战略,海洋工程是打造这一战略的硬核.海洋工程的建造是庞大而复杂的工程,设计过程中海洋环境参数的差之毫厘可能造成重大损失.海洋工程建设面临的一个关键技术问题即海洋工程重要环境设计参数确定的理论和方法,这是近年来研究的热点难题.海洋工程重要环境设计参数确定的基本技术路线如图1所示.
Main observation and conclusionrnEndonuclease Ⅳ (Endo Ⅳ) has the side activity to cleave the apurinic/apyrimidinic site in the single-stranded DNA probe (AP-ssDNA),which adversely affects its performance in single-nucleotide variation (SNV) detection.In t
Main observation and conclusionrnThe catalytic properties of the CeO2 catalyst for propane dehydrogenation (PDH) are examined by employing the density functional theory calculations.Surface modifications and their effects on the surface reactivity are exp