Wind erosion of saline playa sediments and its ecological effects in Ebinur Lake,Xinjiang, China

In many arid and semiarid areas, dry lake beds (saline playa) represent a tremendous source of unconsolidated salt-rich sediments that are available for aeolian transport. Severe salt-dust storms caused by the erosion of such landforms have become very harmful natural phenomena. In this study, sample analysis and field erosion monitoring of Ebinur Lake was conducted to investigate the salt content, chemical composition, and wind erosion intensity of surface salt-rich sediments. The effects of salt-dust rising from the playa on the growth and physiological health of plants were also evaluated in this study through a leaf dustfall test. The results indicate that water-soluble salts assemble densely on the dry lake bed surface. At a depth of 0–2 cm, the highest salt contents can exceed 40%, with sulfate and chloride being the main anions present and Na⁺, Ca²⁺, and Mg²⁺ being the primary cations. The annual wind erosion rate ranged from 0.48 to 5.6 cm in the northwest portion of the lake and from 0.24 to 0.96 cm in the southeast portion. Salt-dust storms caused by wind erosion of saline playa sediments seriously influenced the normal absorption of minerals by plant leaves. Under the influence of salt-dust storms, plant leaves absorb more Na⁺, but far less K⁺.     

合成孔径雷达对地观测应用中目标感兴趣区域的自动获取

在简要评述国内外对地观测应用中,利用SAR图像进行目标ROI的自动获取方面的研究成果及存在问题的基础上,提出了一种SAR图像目标ROI自动获取新方案,包括SAR图像自动目标检测方案和SAR图像自动目标鉴别方案并解决其中的关键技术。实测数据的实验结果证明了新方案具有稳健性强、适用性广、自动化程度高、计算量小、工程实现易等特点,说明了该方案对于空间对地观测具有广泛的应用前景。     

R─618型钻机大口径钻头用复合型截齿

介绍了一种新型桩基工程中常用的复合型截齿。该截齿经武汉地质勘察基础工程总公司在长江广场与进口截齿和国内仿制截齿应用对比,表现出多项独特性能。     

云南"十五"水工环地质大调查成果丰硕

“十五”期间,云南省水工环地质大调查工作共安排7大项。岩溶水、红层地下水调查及开发示范取得了创新性成果和显著经济社会效益。受政府主管部门委托,编制云南省岩溶石山地区石漠化综合治理规划、红层地下水开发规划。岩溶水开发示范项目建成各类岩溶水源地示范工程21项,解决10．3万人的缺水困难;红层地下水开发示范建成各类裂隙水开采井共263口,解决1．3万人缺水困难。此外,在地质灾害防治、数据库建设、地热资源区划及工作建议等方面获得成果。     

南岭铀多金属成矿带赣南段构造—岩浆演化及富大铀矿成矿条件分析

南岭是一条复杂的构造－岩浆活动带，也是我国重要的铀多金属成矿带。作者在前人丰硕研究成果的基础上，通过地层清理及断代划分，岩性、岩相古地理研究，岩石的年代学及地球化学研究，重磁资料的深层次处理和遥感深层次信息的提取，得出了如下认识：（1）三南－寻乌断裂是一条从早震旦至现代长期活动的东西向深部断裂带；（2）南岭地区地壳经历3次不同规模的南北向开合活动；（3）安远－寻乌地区为－大型热隆伸展构造；（4）初步认为该区具备形成富大铀矿的条件。     

Water-inrush mechanism research mining above karst confined aquifer and applications in North China coalmines

Karst water poses great menace to vast and extensive coal-bearing region in China. The large water bodies which are highly pressurized have caused appalling disasters. This study takes example from the North China coal-bearing region and introduces karst aquifer distribution. It points out the major contributors to karst water burst and its relation with bottom plate deformation under mining activities. The analysis of criteria to determine karst water burst focuses on two elements (water burst coefficient and critical water burst index) and their positive application in Huaibei Luling coalmine, North China coal-bearing region. All achievements can be of reference to other coal-producing countries which are confronted with karst water hazards.     

辽宁大板金矿床地质特征及找矿前景

矿床位于辽西台陷北缘,受ＮＥ和ＥＷ向断裂控制,属著名的排山楼金矿外围。前寒武纪斜长角闪岩是主要矿源层。断裂构造为成矿提供空间。金矿化与蚀变带关系密切,蚀变越强金含量越高。属韧性剪切带型金矿,糜棱岩化、斜长角闪质岩石和构造交汇部位是寻找金矿的重要标志。与排山楼金矿对比表明该地区具有找矿前景。     

Dietary Analysis of Marine Fish Species: Enhancing the Detection of Prey-Specific DNA Sequences via High-Throughput Sequencing Using Blocking Primers

Dietary studies of fish can enhance our understanding of predator-prey interactions and provide important insights into complex marine food webs. In this study, we performed dietary analyses of three commercially important fish species in South China: Acanthopagrus latus, Pampus argenteus, and Scomberomorus commerson. Two distinct fragments of the mitochondrial cytochrome c oxidase I (mtCOI) gene, a small (130 bp) and large (300 bp) amplicon, were amplified from the DNA extracted from the gut contents in the presence of blocking primers designed to inhibit the amplification of predator-specific DNA. The amplicons from each predator species were tagged with a unique indexing bar code and sequenced using the Illumina MiSeq platform. Our results showed that the three fish species consumed a wide variety of prey, including jellyfish, copepods, crustaceans, and fish. Seasonal variations in prey composition and species-selective predation were observed. Our approach of combining next-generation sequencing with blocking primers greatly enhanced the speed and resolution of the dietary analyses in marine fishes and could provide novel insights into marine ecosystems.     

Chalcophile element geochemistry of the Baima layered intrusion, Emeishan Large Igneous Province, SW China: implications for sulfur saturation history and genetic relationship with high-Ti basalts

The Permian Baima mafic layered intrusion, believed to be related to the S-undersaturated Emeishan high-Ti basalts, hosts a giant Fe–Ti-V oxide deposit in the lower part of the intrusion. Uniformly high Cu/Pd (1.9 × 10⁶–6.1 × 10⁴) and low Pd/Zr (<0.1) indicate that the Baima parental magma experienced prior sulfide segregation. Mantle-liked δ³⁴S values and low S/Se values indicate negligible external sulfur addition. Primitive mantle-normalized PGE patterns and MELTS calculations indicate that extensive fractional crystallization (~59 %) of chromite, olivine and pyroxene at depth drove the primitive picritic magma to S saturation. Strong positive correlation between IPGE and PPGE and between PGE and V, Cr and S suggest that magmatic sulfide is the dominant mineral controlling the distribution of PGE in the Baima intrusion. A positive correlation between S and Cr, FeO_T + TiO₂ and V content, together with MELTS calculations, indicate that the parental magma of the Baima intrusion reached a second stage of S saturation in the shallower Baima magma chamber, which was likely triggered by decreasing Fe²⁺ accompanying magnetite precipitation. Primitive mantle-normalized PGE patterns for Baima intrusion rocks display similar trends to high-Ti basalts inside the Panxi area, suggesting that they are comagmatic, and following a similar differentiation trend. However, the lavas erupted before they reached sulfide saturation. The more evolved nature of high-Ti basalts outside the Panxi area indicate that they experienced more extensive pre-eruption fractional crystallization. Further fractional crystallization process led these lavas show more PGE fractionated feature.     

EFFECTS OF LAND USE CHANGES ON THE CARBON STORAGE OF TERRESTRIAL ECOSYSTEM——A CASE STUDY OF HULUN LAKE AND TAIHU LAKE BASINS

土地利用和覆被变化对陆地生态系统碳循环有着显著的影响,研究土地利用变化对陆地生态系统碳储量的影响,有利于揭示人类活动和气候变化对陆地生态系统碳循环的驱动机制,同时为制定合理的区域碳排放政策提供参考.本研究采用1980年、1995年、2000年和2005年4期遥感影像解译的土地利用数据,借助IPCC第四次报告推荐的计算方法和对应参数,选择我国东部亚热带和温带的两个典型大湖——太湖流域和呼伦湖流域1980～2005年碳收支情况进行估算,结果表明:1)1980～2005年太湖流域的土地利用结构变化主要表现为农田的逐年减少和聚居地的持续增长,而呼伦湖流域则主要表现为由于林地向草地的转化和草地向其他土地的转化所导致的林地面积的减少和其他土地面积的增加.2)在碳源/汇方面,太湖流域和呼伦湖流域均表现为碳汇,对于太湖流域来说,林地和农田是主要的碳汇,聚居地是碳支出的主要贡献者,2000年以来呼伦湖流域固碳能力出现比较明显的下降,林地和草地的变化是导致碳储量变化的主导因素.3)通过两个流域碳储量变化情况的比较,发现人类活动对陆地生态系统碳储量的影响较为显著;此外,植被类型差异以及成林时间也是影响固碳能力的主要原因.