Trans-Arctic shipping routes expanding faster than the model projections

Rapid declines in Arctic sea ice coverage over the past four decades have increased the commercial feasibility of trans-Arctic routes. However, the historical changes in navigability of trans-Arctic routes remain unclear, and projections by global circulation models (GCMs) contain large uncertainties since they cannot simulate long-term Arctic sea ice changes. In this study, we determined the changes in trans-Arctic routes from 1979 to 2019 by combining two harmonized high-quality daily sea ice products. We found that the trans-Arctic routes are becoming navigable much faster than projected by the GCMs. The navigation season for open water (OW) vessels along the Northeast Passage (NEP) has lengthened from occasionally navigable in the 1980 s to 92 ± 15 days in the 2010 s. In contrast, previous GCM projections have suggested that navigability would not be achieved until the mid-21st century. The 90-day safety shipping area for OW vessels expanded by 35% during 1979–2018, reaching 8.28 million km² in 2018, indicating an increasing rate of 0.08 ± 0.01 million km² per year. The shortest trans-Arctic routes were also shifted further north than the model projections. Regular ships have been able to safely travel north along the islands in the NEP and transit through the M’Clure Strait in the Canadian Arctic Archipelago during the 2010 s, while previous studies have projected that this would not be feasible until the mid-21st century. We also found that the improved navigability of trans-Arctic routes enables commercial ships to transport approximately 33–66% (at the same load factor) more goods from East Asia to Europe during the Arctic shipping season than by the traditional Suez Canal route. These findings highlight the need for aggressive actions to develop mandatory rules that promote navigation safety and strengthen environmental protection in the Arctic.     

The Synergism between Methanogens and Methanotrophs and the Nature of their Contributions to the Seasonal Variation of Methane Fluxes in a Wetland: The Case of Dajiuhu Subalpine Peatland

Wetland ecosystems are the most important natural methane (CH₄) sources, whose fluxes periodically fluctuate. Methanogens (methane producers) and methanotrophs (methane consumers) are considered key factors affecting CH₄ fluxes in wetlands. However, the symbiotic relationship between methanogens and methanotrophs remains unclear. To help close this research gap, we collected and analyzed samples from four soil depths in the Dajiuhu subalpine peatland in January, April, July, and October 2019 and acquired seasonal methane flux data from an eddy covariance (EC) system, and investigated relationships. A phylogenetic molecular ecological networks (pMENs) analysis was used to identify keystone species and the seasonal variations of the co-occurrence patterns of methanogenic and methanotrophic communities. The results indicate that the seasonal variations of the interactions between methanogenic and methanotrophic communities contributed to CH₄ emissions in wetlands. The keystone species discerned by the network analysis also showed their importance in mediating CH₄ fluxes. Methane (CH₄) emissions in wetlands were lowest in spring; during this period, the most complex interactions between microbes were observed, with intense competition among methanogens while methanotrophs demonstrated better cooperation. Reverse patterns manifested themselves in summer when the highest CH₄ flux was observed. Methanoregula formicica was negatively correlated with CH₄ fluxes and occupied the largest ecological niches in the spring network. In contrast, both Methanocella arvoryzae and Methylocystaceae demonstrated positive correlations with CH₄ fluxes and were better adapted to the microbial community in the summer. In addition, soil temperature and nitrogen were regarded as significant environmental factors to CH₄ fluxes. This study was successful in explaining the seasonal patterns and microbial driving mechanisms of CH₄ emissions in wetlands.     

Climate discourses as barriers to rights-based adaptive social protection: How historical politics shape Ethiopia’s climate-smart safety net

A rights-based approach to ‘adaptive social protection’ holds promise as a policy measure to address structural dimensions of vulnerability to climate change such as inequality and marginalisation, yet it has been failing to gain traction against production and growth-oriented interventions. Through the lens of Ethiopia’s flagship Productive Safety Net Programme (PSNP), we trace the role of climate discourses in impeding progress towards socially transformative outcomes, despite the importance of social protection for building resilience. We argue that intertwining narratives of moral leadership and green growth associated with Ethiopia’s national climate strategy shape how the PSNP is rendered ‘climate-smart’. These narratives, however, are embedded within politics that have historically underpinned the country’s drive for modernisation and growth-oriented policies, particularly in dealing with food insecurity. Like pre-existing narratives on development and the environment, they rationalise the presence of a strong central State and its control over natural resources and rural livelihoods. The PSNP is thus conditioned to favour technocratic, productivist approaches to adapting to climate change that may help reproduce, rather than challenge the entrenched politics at the root of vulnerability. Ultimately, this case study demonstrates how climate discourses risk diluting core rights-based dimensions of social protection, contradicting efforts to address the structural dimensions of vulnerability to climate change.     

震后茂县牟托村堆积物特征与植被分布关系

"5·12"大地震后,茂县牟托地区的地形地貌和生态系统受到很大的破坏。本文对茂县牟托地区典型斜坡的植物生长状况、土壤颗粒组成、土壤含水率进行了调查分析,获得了土壤颗粒大小、渗透性、含水率与植物生长之间的关系;研究表明,土壤颗粒组成中,细颗粒所占比例越高,其渗透系数越小,土壤含水率越大,植物的生长状况愈佳;土壤细颗粒所占比例相近的情况下,含水率高的地区植物生长好。根据研究成果,结合生态恢复的技术和方案实施的安全性以及可行性,提出水泥喷灌、修筑挡水阶梯和排水沟、种植植物等生态恢复的方案以及保持斜坡稳定的措施。     

浅析“大同睡佛”断块山地貌景观的成因及保护

地质遗迹是地球发展变化过程中给人类留下的宝贵财富,具有科研价值、学术价值及观赏价值.“大同睡佛”断块山地貌景观与大同云冈石窟遥相呼应,对发展当地的旅游事业有重要意义.根据“大同睡佛”断块山地貌景观区的地质特征探讨了其形成原因,提出了对大同保护措施建议.     

钻孔护壁与堵漏技术——以钱营孜煤矿东一采区补勘为例

钱营孜煤矿东一采区地层复杂,在基岩胶结界面附近易发生钻孔漏失,给钻探施工造成困难,通过分析钻孔漏失原因,根据施工地层情况,有针对性的采取护壁与堵漏技术措施,确保了钻探施工任务完成.     

秦皇岛地质环境综述

通过大量野外调查和对已有成果的分析,发现该地区地质环境破坏严重,并有恶化的趋势.该地区主要地质环境问题包括地质灾害、水环境污染、海水入侵和海岸蚀退,多数为人为因素引发,自然灾害是次要灾害.最后针对不同的地质环境问题提出综合保护建议.     

吉林永吉县大黑山钼矿区矿山地质环境保护与治理

介绍了吉林永吉县大黑山钼矿区的基本情况和矿山地质环境影响现状,并提出了相应的环境治理措施。     

大力推广浅层地热能开发利用 促进崇明生态建设与环境保护

浅层地热能开发利用是崇明生态岛建设的重要工作内容。结合崇明县经济社会发展规划,充分发挥绿色能源示范县建设的作用,推进浅层地热能开发利用管理机制建设,将促进崇明生态岛建设与环境保护。     

攀西钒钛磁铁矿整装勘查复杂地层钻探护壁堵漏技术

攀枝花地区米易县白马钒钛磁铁矿整装勘查工作是四川省地勘基金启动项目,任务重、时间紧,加之所在区域地层复杂,上部漏失,下部多遇断层破碎带,造成钻孔事故频发,钻探效率低下,甚至无法施工,严重阻碍了勘查工程的顺利推进。针对这一施工难题,通过反复试验研究,探索出了一整套行之有效的深孔复杂地层护壁堵漏技术体系,确保了整装勘查项目的顺利完成。详细介绍了该矿区泥浆护壁堵漏技术及其效果。