基于相对风险模型的土地利用变化生态风险定量评价——以石羊河流域为例

土地利用是否合理是推进国民经济发展的关键,也是生态环境变化的风向标。通过理论研究和实地调研,构建了土地利用生态风险定量评价体系,借助相对风险模型（RRM）对石羊河流域的生态风险及其影响因素进行研究。结果表明：（1）在划分的3个评价单元中,中部绿洲生态保护区在土地利用中面临的生态风险最大,北部盆地防沙治沙区次之,南部山地水源涵养区生态风险最小;（2）在3大风险单元的6类不同风险源中,工程建设对石羊河流域的生态风险影响最大,其次是作物种植和畜牧养殖,且在自然环境相对较好的区域表现得尤为明显。     

Tracking embodied carbon flows in the Belt and Road regions

In the past few decades, economic globalization has driven rapid growth of cross-border trade and a new international division of labor, leading to increasing inter- country embodied carbon flows. Multi-region input-output (MRIO) analysis is used to identify embodied carbon flows between major world regions, including seven regions along the Belt and Road (BR), and the spatial distribution of production- and consumption-based carbon intensities. The results show that current embodied carbon flows are virtually all from BR regions to developed countries, with more than 95% of world net embodied carbon exports coming from BR regions. Consumption in the United States and European Union countries induce about 30% of the carbon emissions in most BR regions, indicating that the former bear a high proportion of consumers’ responsibility for the carbon emitted in the latter. For this reason, measuring environmental responsibilities from consumption rather than a production- based perspective is more equitable, while developing countries should be given a louder voice in the construction through dialogue and cooperation, in part in the context of the Belt and Road Initiative, of an inclusive global climate governance system.     

Chinese overseas industrial parks in Southeast Asia: An examination of policy mobility from the perspective of embeddedness

The development of overseas industrial parks is a key component of the Belt and Road Initiative and an expected experimental way of promoting inclusive globalization by inventing new forms of cooperation between China and local host countries. Policy mobility, a classic theory within international political geography addressing the connection between local and global policies, has implications for overseas industrial parks development. In this paper, we argue that policies are not easily moved directly from one place to another; instead, policies are embedded due to the role of local actors in policy mobility. This article first provides an overview of seven China-Southeast Asia economic and trade cooperation zones identified by the Ministry of Commerce, and analyzes their key participants. It then discusses policy mobility by looking into the roles of revenue, land, and talent in developing these industrial parks. The paper finds that these parks face challenges, such as the complicated geographical environments of host countries, huge pressure from enterprise investment capital, the lack of overseas service platforms, and underdeveloped agglomeration economies. In the light of the current situation, policy suggestions for the future sustainable development of overseas industrial parks are put forward.     

乌兰布和沙漠东北缘地表风沙流结构特征

在国家林业局磴口荒漠生态站长期监测的基础上,利用多种积沙仪,对乌兰布和沙漠东北缘流动沙丘、油蒿半固定沙丘、白刺半固定沙丘、油蒿固定沙丘、白刺固定沙丘5种典型下垫面近地面（0～100 cm）的风沙流输沙量进行了实地观测和对比分析。结果表明：（1） 输沙率（q）随高度（h）增加呈幂函数（q=ah^-b,R²≥0.8409）规律衰减,随风速（v）增大呈幂函数（q=av^b,R²≥0.9256）规律增加,42.8%～70.7%的输沙量分布在10 cm高度内,67.6%～90.0%的输沙量分布于30 cm高度内。当地表植被盖度达到40%以上时,输沙率下降至无植被覆盖地表输沙率的6.6%以下,可有效阻止地表风蚀。（2） 沙物质主要由粒径为50～250 μm的细沙和极细沙构成,各高度层风蚀物粒度组成服从单峰态分布,峰值在100～250 μm。随高度增加,风蚀物粒径范围趋于变窄,粒径趋于更细。（3） 起沙风多出现在WSW和NW方向,占全年起沙风的53.19%。风沙流中跃移输沙、蠕移输沙的空间分布在理论上应与风向频率分布基本一致,差异性主要由各方位风的强度和持续时间等因素导致。研究结果可为该区域防沙工程设计提供理论参考。     

Surface-deformation monitoring in the permafrost regions over the Tibetan Plateau,using Sentinel-1 data

Differential Interferometric Synthetic Aperture Radar(D-In SAR) has been widely used to measure surface deformation over the Tibetan Plateau. However, the accuracy and applicability of the D-In SAR method are not well estimated due to the lack of in-situ validation. In this paper, we mapped the seasonal and long-term displacement of Tanggula(TGL) and Liangdaohe(LDH) permafrost regions with a stack of Sentinel-1 acquisitions using the Small Baseline Subset In SAR(SBAS-In SAR) method. In the TGL region, with its dry soils and sparse vegetation, the In SAR-derived surface-deformation trend was consistent with ground-based leveling results; long-term changes of the active layer showed a settlement rate of around 1 to 3 mm/a due to the melting of ground ice, indicating a degrading permafrost in this area. Around half of the deformation was picked up on monitoring, in contrast with in-situ measurements in LDH, implying that the D-In SAR method remarkably underestimated the surface-deformation. This phenomenon may be induced by the large soil-water content, high vegetation coverage, or a combination of these two factors in this region. This study demonstrates that surface deformation could be mapped accurately for a specific region with Sentinel-1 C-band data, such as in the TGL region.Moreover, although the D-In SAR technology provides an efficient solution for broad surface-deformation monitoring in permafrost regions, it shows a poor performance in the region with high soil-water content and dense vegetation coverage.     

Radiative forcing over China due to albedo change caused by land cover change during 1990–2010

Land cover change affects surface radiation budget and energy balance by chang- ing surface albedo and further impacts the regional and global climate. In this article, high spatial and temporal resolution satellite products were used to analyze the driving mechanism for surface albedo change caused by land cover change during 1990-2010. In addition, the annual-scale radiative forcing caused by surface albedo changes in China＇s 50 ecological regions were calculated to reveal the biophysical mechanisms of land cover change affecting climate change at regional scale. Our results showed that the national land cover changes were mainly caused by land reclamation, grassland desertification and urbanization in past 20 years, which were almost induced by anthropogenic activities. Grassland and forest area decreased by 0.60% and 0.11%, respectively. The area of urban and farmland increased by 0.60% and 0.19%, respectively. The mean radiative forcing caused by land cover changes during 1990-2010 was 0.062 W/m2 in China, indicating a warming climate effect. However, spatial heterogeneity of radiative forcing was huge among different ecological regions. Farmland conversing to urban construction land, the main type of land cover change for the urban and suburban agricultural ecological region in Beijing-Tianjin-Tangshan region, caused an albedo reduction by 0.00456 and a maximum positive radiative forcing of 0.863 WIm2, which was presented as warming climate effects. Grassland and forest conversing to farmland, the main type of land cover change for the temperate humid agricultural and wetland ecological region in Sanjiang Plain, caused an albedo increase by 0.00152 and a maximum negative radiative forcing of 0.184 W/m2, implying cooling climate effects.     

长株潭城市群耕地动态变化及驱动力实证研究

利用长株潭城市群近10年的土地利用调查数据及相关社会经济资料,宏观分析了该区域耕地动态变化的趋势,并用主成分分析和多元逐步回归分析法探讨了耕地数量变化的主要驱动力。结果表明,长株潭城市群耕地资源的时空变化特征显著,耕地呈现出逐年减少的总体趋势;得出社会发展因素、经济增长因素、农业科技水平的提高因素以及国家的相关政策是长株潭城市群耕地资源变化的四大类主要驱动因素;总体上,耕地面积与社会经济发展各因素间的相关系数约低于累计耕地面积与各因素之间的相关系数,说明该区域耕地减少与社会经济发展存在时间上的错位性,即经济和社会发展滞后于对耕地资源的占用。     

一株南极细菌（Pseudoalteromonas sp.）对模拟海水养殖水体的净化作用

试验选用一株高产低温蛋白酶的南极细菌菌株Pseudoalteromonas sp. AN64,从溶解氧、化学需氧量、氨氮、亚硝态氮、pH值5个方面研究了南极细菌对养殖水体的影响。结果显示,随着饲料中蛋白质的散失,水体中蛋白质的含量在第7天达到高峰,溶解氧下降,化学需氧量持续上升,在第11天达最大值9.88 mg/L,并且维持在较高的水平。缺氧条件下,有害物质氨氮和亚硝态氮含量逐渐增加,在第9天和第11天分别达最大值0.65 mg/L和0.352 mg/L,而pH值持续下降,在第9天达最低值5.95。当水体中加入高产蛋白酶的南极菌株AN64后,蛋白质含量在第5天即达高峰,溶解氧无明显变化,化学需氧量在第7天达最高峰,比对照组提前4天,但含量仅约为后者的一半。同时,氨氮和亚硝态氮含量远低于对照组,分别仅为对照的47.7 %和26.5 %,而pH值有小幅下降,维持在6.85到7.52之间。由此可以看出,南极菌株产生的低温蛋白酶可以有效分解海水中的蛋白质,降低水体中的氨氮和亚硝态氮等有害物质,维持pH值的稳定性,为健康养殖提供了有效途径。     

华北平原中尺度低气压的若干事实

本文对产生在太行山东侧华北平原行星边界层内的中尺度低压系统进行了普查分析,同时还使用了专门的探测资料,基本弄清了有关中低压的若干事实;探讨了有利于产生中低压的天气条件和华北地形对形成中低压的重要作用;分析了中低压的某些生消规律。