三峡库区巴东县大型涉水滑坡工程治理效果评价

三峡库区大型涉水滑坡的工程治理效果,已经成为水库能否长期按要求正常运营的关键问题。在统计分析三峡库区二期、三期地质灾害防治工程特点的基础上,以库区巴东县15个典型已治理大型涉水滑坡为研究对象,汇总、分析了其工程防治方案,总结了大型涉水滑坡灾害防治工程措施以抗滑桩工程、护坡工程和排水工程为主的技术特点,并根据多次实际调查结果指出巴东县已治理大型涉水滑坡普遍存在的宏观变形问题。在此基础上,结合工程治理流程、现场调查结果,考虑后期运营时可能发生变化的重要影响因素,采用层次分析法,建立了一个兼具时效性和预见性的多层次、多指标的综合评价体系,并基于综合评价值设定了评价标准,对工程治理效果进行分级。最后,以巴东县XL01滑坡的工程治理效果评价为实例,检验此方法的实用性和有效性,并对巴东县典型已治理大型涉水滑坡的工程治理效果进行评价,结合实际调查结果,指出巴东县大型涉水滑坡工程治理效果良好,但仍存在一些问题。     

新疆奇台硅化木的结构及成分分析

新疆奇台是我国硅化木的重要产地,学者研究和资料表明奇台硅化木是亿万年前树木被SiO2交代的产物。SiO2结合的方式是多种多样的,能形成不同的矿物。根据奇台硅化木的不同颜色,利用偏光显微镜和红外光谱仪对同一块硅化木的3种代表颜色进行测试分析。经研究分析认为:奇台硅化木的结构是木质纤维结构,颜色不同SiO2交代的程度不同。奇台硅化木样品颜色不同物质成分也不同,绿色部分主要的物质成分是玛瑙,黑色部分主要的物质成分是蛋白石,灰色部分主要的物质成分是玉髓。     

Climate control on summer precipitation in the Source Region of Three Rivers,China: East or South Asian summer monsoon?

ABSTRACT

The Source Region of Three Rivers (SRTR) has experienced wetter summer seasons than before in recent decades due to climate change. As the most important source of surface water, precipitation plays a key role in supplying the three largest rivers. This study investigates the impacts of the East Asian summer monsoon (EASM) and the South Asian summer monsoon (SASM) on precipitation in the SRTR. Using wavelet analysis tools, we found that: (i) summer precipitation in the SRTR showed notably different responses to the monsoon variability among the 14 stations studied; (ii) the influence of the EASM and SASM on summer precipitation was stronger in the southern and eastern SRTR; but (iii) this influence quickly dampened from southeast to northwest and became almost indiscernible in the northwestern SRTR. This research may help to increase the accuracy of long-term monsoon-rainfall prediction and improve water resource management in the SRTR.     

长江三峡地区仙女山断裂北端延伸问题探讨

The Xiannvshan fault zone, lying along the western margin of the Huangling anticline, is one of the most important fault zones in the Three Gorges reservoir area. The fault experienced strong activity during the Cenozoic Era. The question of whether the fault zone goes through the Yangtze River has been one of the key problems faced in previous studies as it has a significant influence upon the assessment of geological hazards and earthquake stability in the reservoir area. Based on tectonic and geomorphic observations along the fault zone between the Baixianchi village in Changyang county and Huangkou village in Zigui town, together with the comparisons between the geology in Guizhou and Quyuan town in the north bank of the Yangtze River and the Xiannvshan fault zone, it is suggested that the north end of this fault zone is located around Huangkou village and does not go through the Yangtze rivers northward. The evidence is as follows: ① On the basis of field data collection, it is found that the Xiannvshan Fault zone, which stretches 80km, underwent thrust movement in the Cenozoic period, resulting in ravines and fault scarps, topographically. Whereas, on the northern bank of the Yangtze River, faults are rarely found, and most of the faults are developed in the Jurassic strata,without topographical effects. Therefore, the Xiannvshan Fault zone has not stretched to the north bank of the Yangtze River. ② The fault gouge and tectonite zone were found developed on the Xiannvshan Fault zone at Baixianchi village, but only a tectonite zone was found at Zhouping village. There are also some branch faults close to the northern end of the fault zone. So, the activity of the fault zone weakened from south to north in Cenozoic. The fault zone extends northward and dies out at Huangkou. It doesn’t stretch forward any longer as indicated by continuous strata, sparse joints, and small folds, etc.     

菲律宾蛤仔(Ruditapes philippinarum)紫壳内面和白黄壳内面品系的三元杂交

于2010年6月,以性状优良的白黄壳内面F2代菲律宾蛤仔二元杂交系(WO)与紫壳内面F2代选育系(P)为材料,进行了三元杂交研究,获得了三元正反交组合PWO、WOP,并且比较了各实验组子代在不同阶段生长、存活和变态的杂种优势。结果表明:(1)从生长上看。三元杂交子WOP生长始终最快,2个三元正反交组幼虫均表现出了不同程度的杂种优势,其生长主要受卵源与配对策略的交互作用影响。(2)从存活力上看。三元杂交子PWO幼虫及WOP稚贝表现出一定的杂种优势,卵源是浮游期幼虫存活的最主要影响因素。(3)从变态上看,三元杂交子PWO呈现出一定的变态优势为HmPWO=9.80,卵源、配对策略及交互作用均是影响变态主要因素。     

Roles and functions of tourism destinations in tourism region of south anhui: A tourist flow network perspective

Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the perspective of relationship.This article conducted an empirical analysis for Tourism Region of South Anhui(TRSA) and revealed the necessity and feasibility of studying the roles and functions of destinations from tourist flow network’s perspective.The automorphic equivalence analysis and centrality analysis were used to classify 16 destinations in TRSA into six role types:tourist flow distribution center,hub of tourist flows,passageway destination,common touring destination,attached touring destination,and nearly isolated destination.Some suggestions were given on suitable infrastructure construction and destinations service designs according to their functions in network.This destination role positioning was based on tourist flow network structure in integral and macroscopic way.It provided an important reference for the balanced and harmonious development of all the destinations of TRSA.In addition,this article verified the applicability of social network analysis on tourist flow research in local scale,and expanded this method to destination role and function positioning.     

Non-point-source nitrogen and phosphorus loadings from a small watershed in the Three Gorges Reservoir area

Non-point-source pollution has become a major threat to the water quality of the Three Gorges Reservoir(TGR);however,nutrient loadings from terrestrial sources are unclear due to a lack of in situ monitoring.A representative small watershed in the central part of the TGR area was selected to monitor the loss of nitrogen(N) and phosphorous(P) continuously along with the runoff from 2007 through 2009 to understand the exact sources and loadings.Results show that the non-point-source nitrogen and phosphorus comes mainly from the storm runoff from residential areas,citrus orchards and sloping croplands,which contributes up to 76% of the loadings in this watershed.Thus,a crucial measure for controlling non-point-source pollution is to intercept storm runoff from the three sources.Paddy fields provide a sink for non-point-source N and P by intercepting the runoff and sediment along with their different forms of nitrogen and phosphorus.The N and P removal efficiency by paddy fields from residential areas is within the range of 56% to 98%.Paddy fields are an important land-use option for reducing the non-point-source loading of N and P in the TGR area.     

徐州市公交便捷度分析

通过公式计算了徐州市区的各公交站点功能分,在此基础上运用ArcGIS软件将徐州市区地图进行单元划分,形成公交站区;然后将各公交站区的功能分进行属性赋值,并进行空间分析,得出徐州市区公交分布由公交便捷度大致从市中心及火车站向外扩展为四级,并且公交站点的便捷度均由站点向外呈衰减趋势,且衰减程度越来越明显,尤其是位于公交便捷度低的区域更为明显;最后将公交便捷度泰森多边形分布图与人口密度泰森多边形分布图进行叠加分析,得出目前徐州市公交便捷度与人口密度分布的匹配适应性以主城区向外围逐渐增强,一些地区的公交便捷度还不能满足人口密度分布的状况。     

巴麦地区石炭系小海子组储层特征及控制因素分析

在岩心观察、铸体薄片、扫描电镜资料分析的基础上,结合孔隙度、渗透率等物性资料,分析巴麦地区石炭系小海子组储层特征及控制因素.结果表明:该组的储集层岩石类型中,白云岩储层物性较灰岩好,而颗粒灰(云)岩物性也较非颗粒灰(云)岩好;储集空间类型以粒间溶孔、粒内溶孔和晶间溶孔为主;沉积相带、成岩作用及构造作用等是影响研究区储层物性的重要条件,其中高能的台地滩相储集岩是有利储层的发育地带,大气淡水暴露溶蚀作用和白云岩化作用改善了储集空间,构造破裂作用所产生的裂缝使储层物性得到进一步改善.该研究对认识巴麦地区小海子组储层特征及主控因素有参考意义.     

三江源地区草地生态系统服务价值评估

三江源地区的草地生态系统对于维持区域生态平衡和保障社会经济可持续发展具有重要意义。本文基于千年生态系统评估(Millennium Ecosystem Assessment, MA)的生态系统服务分类体系, 采用多种方法对三江源草地生态系统的9 项服务价值逐项进行了评估, 得出2000 年三江源草地生态系统服务价值为562.60 亿元, 其中价值最高的两种服务类型依次为气候调节和食物生产, 分别达259.09 亿元和111.68 亿元, 贡献率分别为46.05%、19.85%。按照草地类型划分, 高寒草甸和高寒草原服务价值分别为490.95 亿元、64.68 亿元, 占总服务价值的87.42%和11.52%。虽然沼泽单位面积服务价值最高, 为4230.77 元/hm², 但在草地生态系统面积中所占比例较低, 总价值相对很低。本文关于三江源草地生态系统的评估结果可以为制定区域生态保护和生态补偿政策提供科学支撑。