人工示踪方法评价地下水入渗补给及其优先流程度——以河北栾城和衡水为例

利用传统人工示踪剂峰值方法评价地下水入渗补给存在精度低和适用性差等缺点。为此,本文提出了多区模型方法,采用保守型示踪剂溴和氚对河北栾城和衡水地区进行了不同土地利用方式和不同深度下地下水入渗补给评价。结果表明,栾城和衡水地区地下水入渗补给量分别为124.3 mm/a和13.7 mm/a,与传统方法(103.3 mm/a和0.0 mm/a)相比,多区模型方法的评价结果更符合实际。同时对由优先流引起的地下水入渗补给量进行了分析,栾城和衡水地区优先流程度分别为28.7%和2.3%。秸秆覆盖抑制降雨或灌溉水入渗补给地下水,降低优先流程度,而植被覆盖有利于土壤水优先流的形成。地下水入渗补给量及其优先流程度与示踪深度均无明显相关性,且受土壤结构控制。     

COVID-19疫情对中国区域经济及产业的影响

科学评估重大突发公共卫生事件的经济系统影响,调控其负效应,提升经济系统韧性,是国家重要战略需求。目前,新型冠状病毒肺炎（COVID-19）疫情在中国得以有效遏制,而外源性输入与局部风险仍存,系统辨识其影响路径与作用强度,对经济系统恢复具有指导意义。基于改进的中国多区域一般均衡分析模型,测度了中国不同疫情风险等级区的经济与产业影响,模拟了生产资料供给和产品需求变化下产业经济发展趋势及受损程度。结果表明,宏观经济层面,2020年中国GDP相比常态损失约0.4%~0.8%,导致短期消费平均下降约2%,就业平均下降约0.7%,而物价平均上涨约0.9%。产业经济层面,疫情对消费型及劳动密集型产业短期冲击最大,如服务业产值相比常态下降6.3%。从疫情对产业经济系统的影响分区来看,受疫情影响冲击较大的省份是风险一级区湖北省,呈现出以湖北为中心向四周扩散的蔓延格局,而不同地区受损的主要产业存在显著差异。此外,复工复产和积极财政政策两类疫情应对情景下区域经济系统的恢复强度模拟结果显示,相较于有序复工复产,增加财政刺激政策对GDP的提升率高了0.3%,但物价水平上涨约1.8%,而复工复产举措拉动产业恢复的辐射空间范围更广。     

The impact of COVID-19 on China’s regional economies and industries

Scientifically assessing the economic impact of major public health emergencies,containing their negative effects,and enhancing the resilience of an economy are important national strategic needs.The new coronavirus disease (COVID-19) has,to date,been effectively contained in China,but the threat of imported cases and local risks still exist.The systematic identification of the virus's path of influence and intensity is significant for economic recovery.This study is based on a refined multi-regional general equilibrium analysis model,which measures the economic and industrial impacts at different epidemic risk levels in China and simulates development trends and the degree of damage to industries and the economy under changes to supplies of production materials and product demand.The results show that,at the macroeconomic level,China's GDP will decline about 0.4％ to 0.8％ compared to normal in 2020,with an average drop of about 2％ in short-term consumption,an average drop in employment of about 0.7％,and an average increase in prices of about 0.9％.At the industry level,the epidemic will have the greatest short-term impact on consumer and laborintensive industries.For example,the output value of the service industry will fall 6.3％ compared to normal.Looking at the impact of the epidemic on the industrial system,the province most affected by the epidemic is Hubei,which is the only province in China in the level-1 risk category.As the disease spread outward from Hubei,there were clear differences in the main industries that were impacted in different regions.In addition,simulation results of recovery intensity of regional economies under the two epidemic response scenarios of resumption of work and production and active fiscal stimulus policies show that an increase in fiscal stimulus policies produces a 0.3％ higher rate of gross regional product growth but it causes commodity prices to rise by about 1.8％.Measures to resume work and production offer a wider scope for industrial recovery.     

“一带一路”沿线地区隐含碳流动研究

随着全球各区域的连通性不断增强,碳流动以及碳泄漏在全球碳减排过程中扮演着越来越重要的角色。伴随全球产业跨境转移的过程,发达国家的高碳行业逐渐转移到发展中国家,并从这些国家进口成品用于自身最终消费。基于多区域投入产出分析,本文测算了“一带一路”沿线地区隐含碳流动,分析了生产碳及消费碳强度在全球的空间分布,并以此为基础探讨了“一带一路”沿线地区的生产者及消费者责任。结果显示,“一带一路”沿线地区的生产碳强度大都高于消费碳强度,且两者的差值大多高于“一带一路”区域外发达地区。全球95%以上的隐含碳净流出发生在“一带一路”沿线地区,美国、西欧等发达国家/地区的消费所引发的“一带一路”沿线主要区域直接碳排放占比约为30%。考虑到跨国贸易中的隐含碳排放,“一带一路”沿线地区整体承受了较大的碳排放压力。从消费者责任着手衡量各国家/地区在全球气候变化中的碳排放责任,并以包容性全球化为基础推进“一带一路”气候治理体系构建,可为长期难以达成协议的全球气候治理问题提供有效思路。     

Towards meaningful consumption-based planetary boundary indicators: The phosphorus exceedance footprint

The idea of measuring humanity’s footprint against planetary boundaries has attracted wide academic attention but methods to implement the theory in sustainability accounting remain underexplored. To help nations take collective actions to stay within a safe operating space, footprinting approaches need to be revised to accommodate biophysical limits. Here we develop a novel sustainability indicator, the phosphorus exceedance footprint (PEF) that measures countries’ contributions to the transgression of the planetary boundaries for phosphorus. Adopting a consumption-based perspective reveals how nations contribute to environmentally unsustainable phosphorus pollution in their trading partners. This captures country-specific transgression through supply chains in a way that complements conventional footprinting. In 2011, 27% of the world’s PEF was associated with international trade flows. Wealthier countries tend to reduce their domestic phosphorus fertiliser exceedance, thus preserving their own natural environment, while increasing their share of imported P-embodied products through trade. A pattern of highly uneven distribution of phosphorus-compromised economies is revealed, with 76% of the worldwide exceeded phosphorus embodied in exports supplied by only four countries: China (42%), Brazil (19%), India (10%) and New Zealand (54%). All countries transgress phosphorus planetary boundaries, even those that do not exceed their own territorial boundaries. Our findings highlight that mitigation strategies need to include international cooperation on increasing the efficiency of fertiliser use and reducing the demand of products that cause phosphorus exceedance.