大连市蒸发量变化特征及影响因子

采用线性倾向估计法和累积距平曲线和完全相关系数法,分析了1951—2001年大连市蒸发量变化特征及其影响因子。结果表明：大连市年蒸发量呈增加趋势,其中夏季蒸发量的增加趋势最为明显,其次为春季,秋季和冬季蒸发量增加趋势不显著;年蒸发量的增加主要来自夏季的贡献。大连市年及四季蒸发量与日照时数、平均地面温度、平均气温日较差和平均风速总体上呈正相关,与平均相对湿度呈负相关。平均相对湿度减小和平均地面温度上升是大连市蒸发量增加的主要原因。     

1957—2009年南澳蒸发量变化特征及影响因子

利用1957—2009年南澳县小型蒸发皿蒸发量资料,分析了南澳蒸发量的气候变化趋势。结果表明：南澳10月蒸发量最大,2月蒸发量最少;秋季蒸发量最大,夏季次之,冬季最少。1957—2009年蒸发量呈明显下降趋势,20世纪60—90年代基本上是锐减,21世纪的第1个10 a反而上升,平均以7.2 mm/a的趋势下降;11月减幅最大,7月减幅最小;冬季减幅最大,秋季次之,夏季最小。对蒸发量下降的原因分析表明,日照时数和平均风速的减少与蒸发量的减少呈显著相关,是蒸发量减少的主要影响因子;低云量的增多导致日照时数减少;低云量、总云量、相对湿度、降水量、水汽压与蒸发量呈负相关关系,其中低云量、总云量与蒸发量负相关显著。     

鄂尔多斯盆地下石盒子组盒8段储集砂体发育控制因素及沉积模式研究

以鄂尔多斯盆地二叠系下石盒子组盒8段储集砂体为研究对象,在众多前人研究成果的基础上,综合研究了盆地内下石盒子组盒8段沉积演化过程中储集砂体发育特征,主要表现为:岩石类型多样,包括含砾粗砂岩、中粒砂岩、细粒砂岩等;成因复杂:包括冲积扇砂体、河流砂体、辫状河三角洲砂体等;分布广泛:具有广覆式大面积分布特征。在上述基础上,系统深入分析了控制盒8大面积砂体分布的关键因素,主要包括:强物源、多物源供给是基础,多水系发育是前提,平缓古地貌是背景,高流速河流是动力。其中,强物源、多物源不仅为盆地内提供了丰富碎屑物质,而且控制着盆地内不同区域储集砂体的岩性特征;多水系发育为形成大面积砂体分布提供了条件,发源于物源区向盆地内搬运陆源碎屑物质的六条水浅流急的辫状河道在盆地中部汇合交叉控制着单层砂体厚度及其连片性。平缓古地貌控制着多河道发育和长距离搬运过程中河道摆动、迁移频繁,并相互叠置交叉。高流速河流控制着平缓古地形上发育的多河道不断交叉、复合。并定量计算了盒8段储集砂体沉积时的地形古坡度,平均坡降为1.10m·km^-1,平均坡度为0.063°;古河流水体平均流速为8.31m·s^-1。进而,结合盆地内钻井实际建立了下石盒子组盒8段独具特色的"强物源供给的缓坡浅水辫状河三角洲沉积模式"。     

民勤绿洲1971-2010年沙尘暴特征及影响因素分析

根据1971～2010年民勤近40a气象资料、民勤周边县市沙尘暴资料,详细分析了民勤绿洲沙尘暴变化特征及影响因素,结果表明：①绿洲以局地性沙尘暴为主,但区域性沙尘暴无论是持续时间、伴随的大风强度和成灾性均大于局地性沙尘暴。②一日中局地性和区域性沙尘暴主要出现在下午和傍晚;月际变化除3月份外其它月份局地性均较区域性沙尘暴多,6～8月份偏多明显,各季局地性均比区域性沙尘暴多,夏季偏多明显;年际局地和区域性沙尘暴均为显著减少趋势,年代际为明显减少趋势。③干旱气候、丰富的沙源是民勤多沙尘暴的自然原因,气候的变化和下垫面状况的改善使沙尘暴减少。分析表明气候变暖使大风日数减少、风力减小,从而影响局地和区域性沙尘暴减少,气候变暖使日照时数增长、蒸发增大,从而影响区域性沙尘暴减少,而对局地性沙尘暴的减少影响不大。     

格尔木河中上游水化学变化及其影响因素

格尔木河是柴达木盆地一条重要的河流。通过系统取样和水化学研究,探讨了格尔木河中上游水化学变化特征并揭示了其影响因素。研究表明,雪水河汇入是导致格尔木河水中Na~+、SO_4~(2-)、Cl~-、B_2O_3、Li~+、K~+等组分变化的主要因素。人类活动则导致Ca~(2+)、HCO_3~-、NO_3~(2-)、Sr~(2+)等组分在局部河段出现异常高值。格尔木河水化学变化是自然和人为因素叠加作用造成的。     

辽宁石油资源消耗变化及影响因子模拟分析

以辽宁原油消耗为研究对象,综合运用EKC曲线模型和IPAT模型对辽宁石油资源消耗变化及影响因子进行了模拟分析。结果表明:辽宁处于石油资源消耗的高增长阶段,其极大程度是受经济发展所驱动的。科学技术进步对石油资源消耗有一定程度上的减缓作用,而人口的平稳增长对石油资源退化没有明显的影响;一段时期内,辽宁石油资源消耗还将呈现增长趋势。将2种模型模拟分析方法综合使用,可找出能源可持续性变化的科学依据,为经济发展和环境管理决策提供参考。     

台风移动路径数值预报的影响因子初探

本文对一个区域中α尺度数值预报业务模式进行垂直分层增加和积 云对流参数化改进,并设计八种对比试验方案,对９４０６号台风进行模拟预报,通过 对比分析各方案模拟预报的台风移动路径,探寻数值模式对台风移动路径预报的 影响因子。     

Characteristics analysis and model prediction of sea-salt water intrusion in lower reaches of the Weihe River,Shandong Province,China

Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water in the marine strata. Based on the analysis of sea-salt water intrusion feature, the sea-salt water intrusion is divided into four stages: The occurrence and development stage(1976–1985), the rapid development stage(1986–1990), the slow development stage(1990–2000) and the stable development stage(2000–2015). Based on the comparative analysis of the relationship between seawater intrusion and influencing factors, this paper presents that the groundwater exploitation and the brine resources mining are the main control factors of sea-salt water intrusion. On this basis, we have established a numerical model of the sea-salt water intrusion. Using this model, we predicted the development trend of the sea-salt water intrusion. The results show that if the current development of groundwater and brine is maintained, the sea-salt water intrusion will gradually withdraw; once development of brine stops, sea-salt water will invade again. This provides the scientific basis for the rational exploitation of groundwater and the prevention of sea-salt water intrusion.     

Deforestation dynamics and drivers in different forest types in Latin America: Three decades of studies (1980–2010)

Over the last decades there have been a considerable number of deforestation studies in Latin America reporting lower rates compared with other regions; although these studies are either regional or local and do not allow the comparison of the intraregional variability present among countries or forest types. Here, we present the results obtained from a systematic review of 369 articles (published from 1990 to 2014) about deforestation rates for 17 countries and forest types (tropical lowland, tropical montane, tropical and subtropical dry, subtropical temperate and mixed, and Atlantic forests). Drivers identified as direct or indirect causes of deforestation in the literature were also analysed. With an overall annual deforestation rate of −1.14 (±0.092 SE) in the region, we compared the rates per forest type and country. The results indicate that there is a high variability of forest loss rates among countries and forest types. In general, Chile and Argentina presented the highest deforestation rates (−3.28 and −2.31 yearly average, respectively), followed by Ecuador and Paraguay (−2.19 and −1.89 yearly average, respectively). Atlantic forests (−1.62) and tropical montane forests (−1.55) presented the highest deforestation rates for the region. In particular, tropical lowland forests in Ecuador (−2.42) and tropical dry forests in Mexico (−2.88) and Argentina (−2.20) were the most affected. In most countries, the access to markets and agricultural and forest activities are the main causes of deforestation; however, the causes vary according to the forest types. Deforestation measurements focused at different scales and on different forest types will help governments to improve their reports for international initiatives, such as reducing emissions from deforestation and forest degradation (REDD+) but, more importantly, for developing local policies for the sustainable management of forests and for reducing the deforestation in Latin America.     

马里亚纳海槽区岩芯中浮游有孔虫和CaCO_3溶解及其影响溶解的因素

本文从浮游有孔虫壳体保存,数量,分异度值,底栖类/浮游类比率和CaCO_3含量诸方面讨论马里亚纳海槽区岩芯中溶解及其影响溶解的因素。