黄河中游砒砂岩地区长川流域土地利用变化分析

根据1976年的Landsat-MSS影像数据以及1987年和2000年的Landsat-TM影像数据,应用遥感和地理信息系统手段以及转移矩阵和景观空间格局指数分析方法,对地处黄河中游砒砂岩地区的内蒙古准格尔旗长川流域土地利用及其变化进行研究。结果表明：1)研究区内分布最多的土地利用类型是灌木林地、草地和难利用地,该三个土地利用类型的面积占研究区域总面积75％;2)从1976～2000年期间,虽然乔木和灌木林地的面积明显增加,但同时也存在林地和草地向难利用土地、沙地和农地的转变过程。与此同时水域亦明显减少;3)水土保持生物措施的实施、农田开垦和降雨量偏少可能是导致研究区土地利用变化的主要原因。     

Mineral chemistry,crystallization conditions and magma mixing‐mingling at Orduzu volcano (Malatya), Eastern Anatolia,Turkey

The Middle Miocene Orduzu volcanic suite, which is a part of the widespread Neogene Yamadağ volcanism of Eastern Anatolia, consists of a rhyolitic lava flow, rhyolitic dykes, a trachyandesitic lava flow and basaltic trachyandesitic dykes. Existence of mafic enclaves and globules in some of the volcanic rocks, and microtextures in phenocrysts indicate that magma mingling and mixing between andesitic and basaltic melts played an important role in the evolution of the volcanic suite. Major and trace element characteristics of the volcanic rocks are similar to those formed in convergent margin settings. In particular, incompatible trace element patterns exhibit large depletions in high field strength elements (Nb and Ta) and strong enrichments in both large ion lithofile elements (Ba, Th and U) and light rare earth elements, indicating a strong subduction signature in the source of the volcanic rocks. Furthermore, petrochemical data obtained suggest that parental magmas of rhyolite lava and dykes, and trachyandesite lava and basaltic trachyandesite dykes were derived from subduction‐related enriched lithospheric mantle and metasomatized mantle (± asthenosphere), respectively. A detailed mineralogical study of the volcanic suite shows that plagioclase is the principal phenocryst phase in all of the rock units from the Orduzu volcano. The plagioclase phenocrysts are accompanied by quartz in the rhyolitic lava flows and by two pyroxenes in the trachyandesitic lava flows and basaltic trachyandesitic dykes. Oxide phases in all rocks are magnetite and ilmenite. Calculated crystallization temperatures range from 650°C to 800°C for plagioclase, 745°C–1054°C for biotite, 888°C–915°C for pyroxene and 736°C–841°C for magnetite–ilmenite pairs. Calculated crystallization pressures of pyroxenes vary between 1.24–5.81 kb, and oxygen fugacity range from −14.47 to −12.39. The estimates of magmatic intensive parameters indicate that the initial magma forming the Orduzu volcanic unit began to crystallize in a high‐level magma chamber and then was stored in a shallow reservoir where it underwent intermediate‐mafic mixing. The rhyolitic lava flow and dykes evolved in relatively shallower crustal magma chambers. Copyright © 2007 John Wiley & Sons, Ltd.     

Incorporating the Istanbul-Ankara high-speed railway into the Belt and Road Initiative: Negotiation,institutional alignment and regional development

This article contributes to a small but growing body of multi-sited and multi-scalar research on the Belt and Road Initiative.We focus on relations at the national,regional and international scales,and present original research from China and Turkey,to show how the Istanbul-Ankara high-speed railway has served as a testing ground for China's Belt and Road Initiative(BRI).Its construction was initially funded by the European Investment Bank,but it is now part of the backbone of the Turkish Government's Middle Corridor plan which enhances west-east connectivity and integration with the Caucasus and Central Asia.We show that in contrast to multinational corporations from the OECD that seek to remain footloose,Chinese state-owned enterprises(SOEs)seek to adapt to,apprehend and ultimately shape local in-stitutions.In the case of Turkey this proved difficult given its institutional alignment with the European Union.Thus,while the railway project was completed successfully by a consortium led by a Chinese SOE,Turkey's dynamic and complex regulatory environment discourages Chinese SOEs in the infrastructure sector.We conclude that the Turkish and Chinese gov-ernments are currently pursuing complementary territorial visions yet their cooperation is project-based and pragmatic.     

小流域水分行为、生态效应及其优化调控研究方面的若干问题

把小流域水文生态研究,分解为小流域水分行为、生态效应及其优化调控研究3个方面。在分析国内外研究现状与问题的基础上,指出了其需要系统加以探讨的若干内容,认为由此可构建流域水文生态学的基本框架,进而发展流域水文生态学。     

地表水酸化的研究进展及其湖泊酸化的环境信息研究

通过对发达资本主义国家在其工业化进程中产生的地表水酸化、资源与环境的破坏以及相关研究进展等的简介 ,审视我国大气污染、酸雨的发展趋势 ,预估部分酸雨区存在地表水酸化的潜在危险性。据此以云南高原湖泊洱海和阳宗海为例 ,从湖水矿化度、SO2 -4 离子浓度的动态变化和沉积记录的磁化率变化等分析研究 ,评述湖泊酸化的早期表现和判别标志。     

基于遥感和InVEST模型的白龙江流域景观生物多样性时空格局研究

以甘肃白龙江流域为例,结合遥感、GIS技术和InVEST模型,从景观地理学角度选取区域生境质量、植物净初级生产力和景观状态指数为评价指标,构建区域景观尺度上生物多样性空间格局综合评估方法,并在栅格像元尺度上开展白龙江流域景观生物多样性时空变化特征分析。结果表明：白龙江流域景观生物多样性空间格局差异显著,其生物多样性高值区主要集中在自然保护区和林业管护区,低值区主要分布在舟曲-武都-文县的白龙江两岸及其以北区域、宕昌县岷江沿岸、高寒稀疏植被区和高山积雪-裸岩区。1990~2010年,流域景观生物多样性较为丰富,整体呈现不断增长的趋势,个别局部区域减弱,其增长区主要体现在生态工程实施区和林业管护区,减少区多分布在人类活动频繁的城乡农耕区和灾害多发区。     

黄土高原丘陵区小流域地下水补给特征

地下水补给量反映了含水层的可更新能力,是地下水资源管理与合理开发利用的关键参数之一。为定量研究黄土高原丘陵沟壑区小流域地下水的补给特征,基于岔巴沟流域上游、中游、下游3个水文站1959-1969年降水与日径流观测资料,通过退水分析法估算了流域地下水补给量,并分析了与降水量和基流量的关系及其在年内的补给变化过程。结果表明：岔巴沟流域年平均基流量为13.09 mm·a^-1,更新时间为124 d,补给量为11.46 mm·a^-1,降水入渗补给率为0.025,基流补给率为0.89。从上游到下游地下水补给量与入渗补给率逐渐增大,且上游与下游之间有显著差异（P<0.05）;基流补给率逐渐减小,各集水区之间差异均显著。地下水补给量与降水量呈线性正相关（R²>0.40）,在下游集水区内随降水量变化的增幅较大。基流量与降水量也呈正相关关系（R²>0.77）,干流基流80%以上源于降水补给转化。以5月份为节点可将地下水补给过程分为"一次补给"和"二次补给"2个主要阶段,其分别占全年总补给量约30%和70%,并且"二次补给"是造成岔巴沟流域不同集水区地下水补给量差异的主要阶段,并且为无资料地区小流域地下水资源的评价提供借鉴。     

太行山淇河流域2000-2015年土壤侵蚀和水源供给变化研究

山地生态系统的土壤侵蚀和水源供给变化对评估区域生态环境质量有重要意义。基于2000-2015年四期土地利用数据,借助InVEST模型对淇河流域近16年间山地生态系统的土壤侵蚀和水源供给变化进行评估。结果表明：① 研究区主要土地利用类型为耕地、草地和林地,共占流域总面积的90%以上。近16年间淇河流域的耕地面积显著减少,草地和水域面积大幅增加,建设用地扩张明显。② 平均土壤侵蚀模数显著降低,2000年土壤侵蚀模数为154.27 t/（hm²·a）,2015年减少到32.09 t/（hm²·a）;强度侵蚀、极强侵蚀和剧烈侵蚀由9.03%、12.19%和25.96%分别减少到7.17%、6.36%和4.21%,微度侵蚀、轻度侵蚀和中度侵蚀由24.31%、16.96%和11.57%增加到41.89%、27.71%和12.68%;退耕还林、还草措施优化了土地利用格局,促进植被恢复,对治理土壤侵蚀起到了显著效果。③ 水源供给量整体呈现先增加后减少的趋势,2005年达到峰值（1.79亿m³）。相邻两期水源供给量增减变化不一,2000-2005年水源供给量增加的面积大于减少的面积,其水源供给的量值也呈增加趋势,水源供给能力整体增强;而2005-2010年、2010-2015年的水源供给能力随之减弱,其中,2010-2015年水源供给减少的较小;林地和草地面积的增加造成水源供给量降低,土壤水源涵养能力增强。土壤侵蚀和水源供给是山地生态脆弱性响应的重要指标,制定合理的水土保持措施对增强山区生态系统的服务能力具有重要意义。     

柴达木盆地盐湖锂矿床成矿过程及分布规律

柴达木盆地盐湖蕴藏230×10~4t锂,集中分布在别勒滩、东西台等4个盐湖,占我国卤水锂资源总量~80%,战略资源地位不言而喻。近年来提锂技术及工程化研究倍受重视,而对盐湖锂矿成因和分布规律的了解凸显不足,锂矿资源流失严重与之不无关联。研究查明,昆仑山高温热泉群含锂泉水长期注入洪—那河,流入终端盐湖,蒸发富集成矿;锂的年输入通量748.8 t,结合区内盐湖锂矿总储量保守估算,成矿期始于14 ka BP之后;洪—那河早期主要流向别勒滩,在山前冲积扇向北推进、扇前河改道北流后,方才形成含锂河水当前分配格局。据此,破解了别勒滩锂矿在研究区储量最大的原由。还查明了锂矿床仅存在于别勒滩,而在达布逊等3个区段不能成矿的原因。阐明了锂的来源与新生代火山喷发岩、深部岩浆房、昆仑大断裂活动有关,以及含锂热水持续远程输送至盐湖成矿的地貌和水文气候动因。企业应当根据锂的分布规律和矿床特征,迅速转变钾肥生产模式。     

Use a Spatial Analysis Model to Assess Habitat Quality in Lashihai Watershed

Habitat quality assessments are of great significance for protecting biodiversity. This study analyzes the changing habitat quality of Lashihai watershed based on SPOT satellite images. We extracted the land use data for Lashihai watershed in Yunnan province for the years 2000 and 2015, and then used an InVEST model to evaluate habitat degradation, habitat quality and habitat scarcity in the study area from 2000 to 2015. Spatial statistical methods were used to determine changes to spatial dynamics. Results indicate that the number of areas with habitat degradation was generally small, and that both the number of areas with habitat degradation and the degree of degradation had fallen noticeably during the fifteen-year study period. In general, the quality of habitats was maintained or improved, while the quality of habitats decreased in only a few areas. The scarcity of habitats for cultivated land had increased, the tension between people and land use was relatively prominent. The reason habitat quality in Lashihai watershed has improved can be attributed to three factors: 1) The policy of returning farmland to forests since 2000 has been well implemented and has achieved remarkable results. Loss of forests from logging and deforestation has basically been eliminated, and great progress has been made restoring the ecological environment. 2) High background value of quality habitat suitability benefits from the research area’s high vegetation coverage. 3) The development of the local tourism economy has transformed the area’s ecological advantages into an economic bonus, greatly increasing the income level and living standards of residents. At the same time, the ecological resource bonus has increased the enthusiasm of residents for ecological protection and has helped to promote the protection of local eco-systems, both reducing ecological degradation and improving habitat quality. At the same time, increasing conflicts between land and people should be addressed. Support is needed to promote development of the ecological economy while continuously reducing ecological degradation and further increasing residents’ income. There must be less reliance on industry and less pressure on both land and people, all the while ensuring that the local economy and ecology can more forward together in a sustainable way.