东南亚生物质燃烧对我国春季PM2.5质量浓度影响的数值模拟

为研究东南亚生物质燃烧对我国的影响,利用NAQPMS(嵌套网格空气质量预报模式系统)模拟分析了2013年3月我国及东南亚污染物质量浓度分布,以及东南亚国家生物质燃烧对我国ρ(PM_2.5)的贡献. 结果表明:NAQPMS模式可较好地再现ρ(PM_2.5)的时空演变规律. 在我国西南部分地区,东南亚生物质燃烧贡献与当地人为源相当,并且在ρ(PM_2.5)较高时尤为明显. 东南亚生物质燃烧对我国的影响主要有两个路径:第一个路径是缅甸向云南等地的输送,对云南ρ(PM_2.5)的月均贡献达到20 μg/m3(贡献率为30%),是云南本地生物质燃烧贡献的2倍左右,日均贡献甚至可达到34 μg/m3(贡献率为43%),高于我国人为源贡献(28 μg/m3)和贡献率(36%);第二个路径是老挝和越南向云南与广西交界的输送, 对南宁ρ(PM_2.5)的月均贡献为10 μg/m3,日均贡献高值区间为20～40 μg/m3. 我国人为源对东南亚的影响较小,对ρ(PM_2.5)月均贡献率在10%以内,主要集中在越南和东南亚南部沿海城市. 东南亚人为源对我国的影响也较小,ρ(PM_2.5)月均贡献在2 μg/m3以下. 研究显示,东南亚生物质燃烧对我国特别是西南地区产生的影响不可忽视.      

Optimal Management of a Multispecies Shorebird Flyway under Sea‐Level Rise

Every year, millions of migratory shorebirds fly through the East Asian–Australasian Flyway between their arctic breeding grounds and Australasia. This flyway includes numerous coastal wetlands in Asia and the Pacific that are used as stopover sites where birds rest and feed. Loss of a few important stopover sites through sea‐level rise (SLR) could cause sudden population declines. We formulated and solved mathematically the problem of how to identify the most important stopover sites to minimize losses of bird populations across flyways by conserving land that facilitates upshore shifts of tidal flats in response to SLR. To guide conservation investment that minimizes losses of migratory bird populations during migration, we developed a spatially explicit flyway model coupled with a maximum flow algorithm. Migratory routes of 10 shorebird taxa were modeled in a graph theoretic framework by representing clusters of important wetlands as nodes and the number of birds flying between 2 nodes as edges. We also evaluated several resource allocation algorithms that required only partial information on flyway connectivity (node strategy, based on the impacts of SLR at nodes; habitat strategy, based on habitat change at sites; population strategy, based on population change at sites; and random investment). The resource allocation algorithms based on flyway information performed on average 15% better than simpler allocations based on patterns of habitat loss or local bird counts. The Yellow Sea region stood out as the most important priority for effective conservation of migratory shorebirds, but investment in this area alone will not ensure the persistence of species across the flyway. The spatial distribution of conservation investments differed enormously according to the severity of SLR and whether information about flyway connectivity was used to guide the prioritizations. With the rapid ongoing loss of coastal wetlands globally, our method provides insight into efficient conservation planning for migratory species. Gestión Óptima de una Ruta Migratoria de Múltiples Especies de Aves Costeras Sometida a Incremento del Nivel del Mar     

Indicators of urban climate resilience: A contextual approach

As urban populations grow and climate exposure increases, more cities are introducing formal planning processes to adapt to climate change. This paper explains the process applied to eight cities in the Asian Cities Climate Change Resilience Network (ACCCRN) for developing indicators for planning and monitoring local climate resilience. This process relied on transferring a common conceptual framework for climate resilience, together with a locally led iterative and collaborative process that engaged technical and planning authorities and vulnerable groups. The process varied slightly between cities and generated indicators that were chosen for their contextual fit and availability of data. The main benefit of developing resilience indicators in this way was the local capacity that the process built, in terms of understanding resilience, shared understanding of concepts and measurement and establishment of a common platform for future planning and monitoring of climate adaptation interventions at the city level.     

Institutions,policies and soil degradation: theoretical examinations and case studies in Southeast China

Abstract

Southeast China is one of the severe soil degradation areas in China. This paper theoretically examines the impact of some important institutional arrangements and policies, like land management pattern, the rural off-farm employment, land property change and changes in prices of agricultural products, on soil degradation in this area. It further conducts some case studies to confirm the potential relationship between the institutions & policies and soil degradation, applying the surveyed and the second hand data. The paper at last makes some conclusions and proposes some suggestions on how to promote soil conservation by improving the ways of policy decision-making and the effects of policies on land use.     

韩江流域河水地球化学特征与硅酸盐岩风化——风化过程硫酸作用

流域岩石化学风化是全球碳循环的重要环节之一,硅酸盐岩风化过程消耗大气CO_2,是在地质时间尺度上调节大气CO_2浓度的重要机制。本工作在对我国东南花岗岩地区流经典型的硅酸盐岩地质背景河流——韩江流域河流水化学组成研究的基础上,分析和定量计算了河流水体主要物质来源,并对硫酸参与岩石风化和碳循环过程的作用进行了分析,进而对韩江流域岩石风化速率及其大气CO_2消耗通量进行了估算。结果表明,韩江流域河流主离子组成主要来源于硅酸盐岩和碳酸盐岩风化,并计算得出约41%的硫酸根离子来自于大气降水;流域碳酸盐岩的风化速率为21.7 t/(km~2·a),硅酸盐岩为18.9 t/(km~2·a)。硫酸参与岩石风化提供的离子贡献占流域岩石风化提供总离子量的65.9%;流域风化带来的CO_2消耗速率被高估了约61%。     

1980—2014年中亚地区植被净初级生产力对气候和CO2变化的响应

中亚干旱区分布着世界80%以上的温带荒漠,受气候变化影响显著。论文首先收集实验观测数据验证了干旱区生态系统模型（AEM）,然后运用AEM开展数值模拟实验量化研究了1980—2014年中亚净初级生产力（NPP）的时空格局,评估了不同环境因子（降水、温度、CO₂）的相对贡献率及其交互效应。结果表明：过去35 a中亚干旱区年均NPP总量为1 125±129 Tg C（1 T=10¹²）或218±25 g C/m²。哈萨克斯坦北部地区年NPP值较高（349±39 g C/m²）,而南疆地区年NPP值较低（123±45 g C/m²）。1980—2014年间,中亚NPP总体呈减少趋势 [-0.71 g C/(m²·a)],南疆极端干旱区的NPP降低最为显著 [-2.05 g C/(m²·a)]。相较于1980—1984年NPP均值,在1985—2014年中亚区域NPP总体降低了118 Tg（-10%）。其中CO₂施肥效应促进NPP增加了99.7 Tg （+8%）,气温升高的正效应促进NPP增加了35.4 Tg（+2%）,而降水减少导致NPP降低了221 Tg（-18%）。研究区内9%的地区的NPP主要控制因子为温度,主要分布在天山和哈萨克斯坦北部等高纬高寒地区。降水主控区面积占整个研究区的69%,主要分布在荒漠平原特别是南疆等植被受水分限制的区域。CO₂主控区占研究区面积的20%,主要分布在天山中山带森林区和低海拔地区等水热条件好的区域。研究表明新疆南部地区是中亚的关键生态脆弱区,其生态安全面临着气候变化的挑战,但21世纪的升温不大可能因刺激自养呼吸而对中亚区域NPP造成显著影响。     

全球变暖背景下中亚兴都库什、喀喇昆仑及天山气候变化研究进展

中亚兴都库什、喀喇昆仑及天山山脉（HKT）是气候变化敏感区,其在全球变暖背景下的气候变化对区域生态和经济系统的稳定性及可持续发展有重要意义。目前对中亚高海拔地区的研究多集中于局部区域,有关HKT地区气候变化的综合对比分析较为缺乏。本文对HKT地区现代气候变化的相关研究成果进行简单梳理和回顾,重点总结了HKT地区气候变化特征、影响机制及其与全球变暖的联系。结果表明：（1）近60 a,HKT地区不同区域气候的时空特征存在差异,从时间上看,天山的年均温及年降水量均呈上升趋势,而兴都库什-喀喇昆仑山的年均温呈不显著增加趋势,其年降水量变化趋势不稳定;从空间上看,HKT地区山脉南坡气温高于北坡,但北坡降水量高于南坡,且天山南北坡年降水均呈上升趋势。（2）HKT地区的气候变化除了受西风环流、南亚印度季风及局地条件等影响外,还受到北大西洋涛动和厄尔尼诺-南方涛动等大尺度气候模态的调制,如兴都库什-喀喇昆仑山脉在NAO正（负）位相和ENSO暖（冷）位相降水趋于增加（减少）。     

中亚跨境流域生态脆弱性评价及其时空特征分析——以阿姆河流域为例

生态脆弱性（EVI）的定量评估和长期分析,对于了解区域生态环境动态变化与指导生态环境保护与修复极为重要。但以往研究很少对跨境流域这一特殊单元进行生态脆弱性评价。以阿姆河流域为例,选择反映研究区植被、水文、气候、地形、土壤以及人类活动等方面的11个指标,通过共线性诊断分析,构建了阿姆河流域生态脆弱性评价体系,利用主观权重与客观权重相结合的方法确定指标权重,对1990-2015年研究区EVI进行了定量评价及时空特征分析。结果表明：（1）研究区生态环境呈恶化趋势,大部分区域处于重度脆弱状态,研究时段内重度脆弱性比例的平均值为46.40%;极度脆弱性占比在过去25年内呈增加趋势,从1990年的2.58%增加至2015年的16.97%,增幅为14.39%。（2）生态脆弱性在不同土地覆被类型之间差异巨大,其中草地的EVI值变化最大,裸地的生态环境最为脆弱,林地的生态脆弱性最小;研究区生态脆弱程度整体表现为裸地>灌丛>草地>耕地>城市用地>林地的规律。（3）EVI与地形因子的关系表明生态环境最为脆弱的区域主要位于低海拔地势平坦与高海拔坡度大的地区,而低脆弱性主要分布在海拔2500~3500 m或坡度15~25°的区间上。     

东北亚冬季PM2.5水溶性离子空间分布特征及来源

为探讨东北亚冬季PM_2.5水溶性离子空间分布特征及来源,测定了2017~2018年沈阳冬季PM_2.5水溶性离子浓度.结果显示：沈阳冬季PM_2.5水溶性离子平均质量浓度为28.5±11.9μg/m³,二次离子（SO₄^2-、NO₃^-和NH₄⁺）的浓度最高,分别占总水溶性离子质量浓度的31.0%、22.4%和19.2%.运用离子化学计量学关系、相关性和主成分分析,探讨了沈阳冬季PM_2.5水溶性离子的可能来源.并整合了东北亚冬季（中国东北、韩国、日本）近20a来PM_2.5水溶性离子数据,发现沿着东亚冬季风,东北亚冬季PM_2.5水溶性离子浓度从中国东北,经韩国海岸、韩国和济州岛,日本海岸至日本整体呈下降趋势,在韩国和日本出现局部上升,且在不同区域,不同水溶性离子占比明显不同.其中,韩国冬季PM_2.5中SO₄^2-、Ca²⁺和K⁺受外来源影响显著,NO₃^-和NH₄⁺主要来自本地源,Cl^-、Na⁺和Mg²⁺主要来自本地源或海源;日本中部冬季PM_2.5中SO₄^2-、NO₃^-、NH₄⁺和K⁺主要来自本地源,Cl^-、Ca²⁺、Na⁺和Mg²⁺主要来自本地源或海源.     

Ethnosciences––A step towards the integration of scientific and indigenous forms of knowledge in the management of natural resources for the future

Integration of indigenous knowledge and ethnoscientific approaches into contemporary frameworks for conservation and sustainable management of natural resources will become increasingly important in policies on an international and national level, both in countries that are industrialised and those that have a developing status. We set the scene on how this can be done by exploring the key conditions and dimensions of a dialogue between ȁ8ontologiesȁ9 and the roles, which ethnosciences could play in this process. First, the roles of ethnosciences in the context of sustainable development were analysed, placing emphasis on the implications arising when western sciences aspire to relate to indigenous forms of␣knowledge. Secondly, the contributions of ethnosciences to such an ȁ8inter- ontological dialogueȁ9 were explored, based on an ethnoecological study of the encounter of sciences and indigenous knowledge in the Andes of Bolivia, and reviewed experiences from mangrove systems in Kenya, India and Sri Lanka, and from case-studies in other ecosystems world-wide, incl. Australia, Burkina Faso, Ecuador, Ethiopia, Guatemala, Indonesia, Nepal, Niger, Philippines, Senegal, South-Africa and Tanzania.