Source model of the 2018 M_(w)7.5 Papua New Guinea earthquake constrained by InSAR measurements: Insight into a blind rupture beneath the New Guinea Highlands

The Southern Highland Fold and Thrust Belt(SHFTB),the boundary of the Australian plate and the New Guinea Highland block,significantly contributes to the convergent deformation along the plate bound-ary.However,due to the lack of observation data,the detailed slip pattern of the SHFTB and the orogenic mechanism beneath the New Guinea Highlands remains controversial.On 25 February 2018,the M_(w)7.5 Papua New Guinea(PNG)earthquake struck the southeastern segment of the SHFTB.The detailed rupture characteristics of this event is significant for further clarifying the inter-seismic slip pattern along the SHFTB.Here,the coseismic deformation field of this earthquake was obtained using high-resolution ALOS-2 satellite images.We find that the 2018 M_(w)7.5 PNG earthquake ruptured a large-scaled fault(SHFTB)extending to the lower crust(deeper than 20 km)beneath the New Guinea Highlands,with a dip angle of 24°.The slips on the fault plane are equivalent to moment magnitudes of M_(w)7.51.Three major asperities with thrust-dominated slip of up to 3.94 m are detected on the fault plane.This finding implies that the slip pattern on the eastern segment of the SHFTB is dominated by thrust,rather than with significant sinistral movement,as previously reported.The tectonic deformation across the New Guinea Highlands is possibly concentrated on the large-scale fault SHFTB and primarily controls the intra-continental orogeny in the central Papua New Guinea.

Timings of early crustal activity in southern highlands of Mars:Periods of crustal stretching and shortening

Extensional and compressional structures are globally abundant on Mars. Distribution of these structures and their ages constrain the crustal stress state and tectonic evolution of the planet. Here in this paper, we report on our investigation over the distribution of the tectonic structures and timings of the associated stress fields from the Noachis-Sabaea region. Thereafter, we hypothesize possible origins in relation to the internal/external processes through detailed morphostructural mapping. In doing so, we have extracted the absolute model ages of these linear tectonic structures using crater size-frequency distribution measurements, buffered crater counting in particular. The estimated ages indicate that the tectonic structures are younger than the mega impacts events(especially Hellas) and instead they reveal two dominant phases of interior dynamics prevailing on the southern highlands, firstly the extensional phase terminating around3.8 Ga forming grabens and then compressional phase around 3.5-3.6 Ga producing wrinkle ridges and lobate scarps. These derived absolute model ages of the grabens exhibit the age ca. 100 Ma younger than the previously documented end of the global extensional phase. The following compressional activity corresponds to the peak of global contraction period in Early Hesperian. Therefore, we conclude that the planet wide heat loss mechanism, involving crustal stretching coupled with gravitationally driven relaxation(i.e.,lithospheric mobility) resulted in the extensional structures around Late Noachian(around 3.8 Ga). Lately cooling related global contraction generated compressional stress ensuing shortening of the upper crust of the southern highlands at the Early Hesperian period(around 3.5-3.6 Ga).

Application of Decision Support System for Agro Technology Transfer (DSSAT) to Simulate Agronomic Practices for Cultivation of Maize in Southern Highland of Tanzania

The southern highlands zone of Tanzania is the one of the most potential area for agriculture contributes up to 46% of the total country’s maize production. However, the rate of maize production tends to decrease with time due of poor agronomic practices. The aim of this study was to simulate the effect of nitrogen dose and plant spacing on grain yields from five selected maize varieties. Decision Support System for Agrotechnology transfer crop model was used for this purpose. Based on the agroecological zones, six sites were selected which includes Ihumbu farm, Mwazye and Nyera Estate Mbozi, Lupa Tinga Tinga, Santilya and Mbinga. Maize varieties H614, Kitumani Composite I, H511, H626 and H612;Spacing (90 × 30 cm and 60 × 30 cm) and nitrogen dose (0, 50, 100, 150 and 200 kg/ha) were simulated. It was found that only H614 (4610.9 kg/ha) and Kitumani Composite I (3998.7 kg/ha) maize varieties performed well at the spacing of 60 × 30 cm and up to the nitrogen dose of 150 kg/ha. Therefore the two maize varieties H614 and Kitumani Composite I could be recommended for cultivation at the spacing of 60 × 30 cm and nitrogen dose of 150 kg/ha for improving production of maize in southern highland of Tanzania.

不同施肥措施对晋南旱塬麦田土壤碳氮变化的影响

【目的】明确不同施肥措施下麦田土壤碳氮库的变化情况,为旱地小麦化肥定量减施及土壤肥力提升提供依据。【方法】于2012―2017年在晋南黄土旱塬冬小麦种植区,设置农户施肥(FF)、监控施肥(MF)和不施肥(NF)3种施肥处理,研究了连续5 a不同施肥措施对旱地麦田耕层土壤总有机碳氮、有机碳氮组分及0～200 cm土层土壤硝态氮累积量的影响。【结果】晋南黄土旱塬麦田,在秸秆还田基础上,连续5 a不施肥(NF)耕层土壤总有机碳较2012年试验前提高了24.7%,而单施化肥处理(FF、MF)下土壤总有机碳下降了2.4%～8.2%。连续单施化肥较不施肥显著提高了可溶性有机碳、轻组有机碳以及可溶性有机氮质量分数,其中传统农户施肥对土壤可溶性有机碳的贡献率显著高于监控施肥处理的。不同施肥处理土壤轻组有机碳在总有机碳中的分配比例为17.9%～31.3%;不施肥处理较单施化肥处理有利于维持较高的土壤重组有机碳量,利于土壤有机碳的固存。不同施肥处理对轻组有机氮和重组有机氮均没有显著影响。传统农户施肥处理0～200 cm土层硝态氮累积量高达426.0 kg/hm^2,且67%集中在100～200 cm土层,具有淋失风险。而监控平衡施肥在累计氮肥投入量减少36.9%基础上,0～200 cm土层硝态氮残留量较农户施肥低51.4%。【结论】黄土旱塬麦区,由于前期农户过量施氮,不施肥种植结合秸秆还田可提高土壤总有机碳量,主要增加了矿物紧密结合态的重组态有机碳量。单施化肥则促进了土壤有机质的矿化分解,提高了土壤中活性有机碳氮量。传统农户施肥模式促使0～200 cm土层产生大量硝态氮残留,具有较高淋失风险。

基于科学人才观的北京南部新区人才高地建设探讨

随着中共中央、国务院"人才强国战略"的提出,人才资源作为科学发展的第一资源,对其进行有效的开发和利用是当前及今后北京南部新区人才高地建设的重要战略步骤。通过对科学人才观的学习和理解,以及对人才资源管理生态系统的分析,结合新区人才工作总体目标定位的实际需求,提出最终实现北京南部新区人才高地建设的策略体系。

Alice Yao,The Ancient Highlands of Southwest China: From the Bronze Age to the Han Empire.Oxford:Oxford University Press,2016.Erica Fox Brindley,Ancient China and the Yue: Perceptions and Identities on the Southern Frontier,c.400 BCE-50 CE.Cambridge:Cambri

Together as well as in and of themselves, these two new books represent a major contribution to research on the Southern reaches of the Chinese empire in ancient times. The sophisticated, in-depth treatment of relations between Chinese centers and southern peripheries is a welcome development that both supplements and illuminates research on the northern heartland of the Chinese empires.

青南高寒草甸秃斑地形成的气象条件分析

通过分析青南高寒草甸秃斑地（简称“黑土滩”）分布地域气温、降水等气候因子与牧草的关系和研究“黑土滩”形成的气象成因，发现干旱气候对青南牧区“黑土滩”的形成起了推波助澜的作用，并加剧了“超载过牧—草地退化—鼠害危害—草畜矛盾突出”的恶性循环，从而促进了“黑土滩”的形成。

“双循环”背景下内陆老区建设开放高地研究——以赣南苏区为例

内陆老区开放高地是新时代内陆地区发挥后发潜力、兼蓄比较禀赋优势与开放机制创新为一体的内陆经济跨越式发展新范式。通过一套开放高地潜力评价指标体系并运用熵权法的研究表明,赣南苏区的经济开放度位势在赣粤闽湘边区中尚不具有优势,与沿海发达地区存在明显差距,但差距呈缩小趋势;赣南苏区在开放高地潜力评价中处于有利的后发位势。因此,推动"双循环"合作平台建设、大力培育出口主导型经济、优化空间开放格局、实施开放型创新驱动战略,将有利于"双循环"下赣南苏区高质量建设内陆开放高地。