变暖背景下陕西极端气候事件变化分析

利用1961-2010年陕西省78个气象观测站的逐日最高温度、最低温度、平均温度以及日降水量资料,采用趋势分析方法对该地区极端气候事件的变化进行了分析。结果表明:①近50 a来陕西降水极端事件没有显著的增减变化趋势,但存在明显的阶段性。②近50 a来区域严重干燥事件在显著增加而严重湿润事件趋于减少,2000年以后严重干湿事件均偏多,区域降水有向不均衡、极端化发展的趋势。③区域年极端高（低）温事件在近50 a来呈现显著的增加（减少）趋势,其空间分布具有较好的一致性。极端温度事件的变化在各季节存在差异,冬、春季变暖的趋势比较显著。在显著变暖的20世纪90年代以后,相对于降水极端事件,温度极端事件显现地更为突出。     

石笋记录的西南地区MIS4阶段夏季风的演化

基于重庆市丰都县羊子洞石笋Y-02的12个²³⁰Th年龄和503个氧同位素数据重建了中国西南地区60~73ka B.P.时段夏季风的演化历史。Y-02的δ¹⁸O记录显示中国季风区D/O18、D/O19a和D/O19共3个千年尺度夏季风增强事件与格陵兰间冰阶（GIS）18~19相对应。此外,Y-02记录显示：紧接着D/O18事件以后,夏季风强度突然减弱,而此时北半球高纬度地区正经历着明显的降温过程。Y-02记录捕捉到的这次东亚夏季风突然且短暂的一次减弱过程,可能是H6事件或者是H6事件季风最弱的时段。Y-02的δ¹⁸O记录显示,D/O18事件是一次较强烈的千年尺度季风增强事件,持续时间近千年,而D/O19事件在持续时间和强度上不如D/O18事件,这不同于格陵兰冰芯记录。中国季风区气候变化与格陵兰地区存在着如此紧密的联系进一步支持：东亚夏季风演化受到北半球高纬度地区气候变化的影响,但是对具体的气候事件响应可能存在不同的模式。

     

Accumulation by securitization: Commercial poaching,neoliberal conservation,and the creation of new wildlife frontiers

Part of a broader interest in the escalating securitization of conservation practice, scholars are beginning to take note of an emerging relationship between conservation–securitization, capital accumulation, and dispossession. We develop the concept of accumulation by securitization to better grasp this trend, positioning it in the critical literatures on neoliberal conservation, green grabbing, and conservation-security. The concept captures the ways in which capital accumulation, often tied to land and resource enclosure, is enabled by practices and logics of security. Security logics, moreover, increasingly provoke the dispossession of vulnerable communities, thereby enabling accumulation. We ground the concept by turning to the Greater Lebombo Conservancy (GLC) in the Mozambican borderlands. This is a new privately-held conservancy built as a securitized buffer zone to obstruct the movement of commercial rhino poachers into South Africa’s adjacent Kruger National Park. We show how wildlife tourism-related accumulation here is enabled by, and in some ways contingent upon, the GLC’s success in curbing poaching incursions, and, relatedly, how security concerns become the grounds upon which resident communities are displaced. In terms of the latter, we suggest security provides a troubling, depoliticized alibi for dispossession. Like broader neoliberal conservation and green grabbing, we illustrate how accumulation by securitization plays out within complex new networks of state and private actors. Yet these significantly expand to include including security actors and others motivated by security concerns.     

基于DMSP/OLS稳定夜间灯光数据的中国1995-2008年电力消费量时空动态研究(英文)

Electric power consumption (EPC) is one of the basic indices for evaluating electric power use. Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployment of electric power resources. In this study, an EPC model was developed using stable nighttime lights time-series data from the Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS). The model was used to reconstruct the spatial patterns of EPC in Chinese Mainland at the county level from 1995 to 2008. In addition, the spatiotemporal dynamics of EPC were analyzed, and the fol-lowing conclusions were drawn. (1) The EPC model reliably represented the spatiotemporal dynamics of EPC in Chinese Mainland with approximately 70% accuracy. (2) The EPC in most regions of Chinese Mainland was at low to moderate levels, with marked temporal and spatial variations; of high-level EPC, 58.26% was concentrated in eastern China. Six urban agglomerations (Beijing-Tianjin-Tangshan region, Shanghai-Nanjing-Hangzhou region, Pearl River Delta, Shandong Peninsula, middle-south of Liaoning Province, and Sichuan Basin) accounted for 10.69% of the total area of Chinese Mainland but consumed 39.23% of the electricity. (3) The EPC of most regions in Chinese Mainland increased from 1995 to 2008, and 64% of the mainland area showed a significant increase in EPC. Moderate increases in EPC were found in 61.62% of eastern China and 80.65% of central China from 1995 to 2008, whereas 75.69% of western China showed no significant increase in EPC. Meanwhile, 77.27%, 89.35%, and 66.72% of the Shanghai-Nanjing-Hangzhou region, Pearl River Delta, and Shandong Peninsula, respectively, showed high-speed increases in EPC. Moderate increases in EPC occurred in 71.12% and 72.13% of the Beijing-Tianjin-Tangshan region and middle-south of Liaoning Province, respectively, while no significant increase occurred in 56.34% of the Sichuan Basin.     

新疆焉耆盆地绿洲景观的空间格局及其变化

通过GIS技术的叠加和提取功能建立了焉耆盆地两个时间段的景观类型转移矩阵。在此基础上,分析了焉耆盆地内部绿洲景观类型的动态演化过程和空间分布特征。结果表明:焉耆盆地经过近40年的土地开垦后,人工绿洲呈现出上升的趋势,农田向自然绿洲和荒漠的扩张在整个研究阶段均可见;农田开垦的对象表现为从草地(含部分沼泽地)→多汁木本盐柴类荒漠→超旱生灌木半灌木荒漠迁移,体现了农田绿洲开垦从易到难,自然绿洲不断缩小,人工绿洲不断扩大的过程;对土地和水资源的不合理利用,导致盆地内湖泊水体、湖泊周边及农田绿洲出现明显的生态退化。焉耆盆地今后的规划和发展必须高度重视人工绿洲生态系统和自然生态之间的平衡,盆地环境治理很大程度决定于水资源的合理利用和合理调节。     

与国际框架接轨的我国矿产资源/储量分类

回顾了我国现行矿产储量分类分级标准的制订情况,分析了其存在的主要问题。简要介绍了《联合国国际储量／ 资源分类框架》。通过新颁发的《固体矿产资源／ 储量分类》国家标准与我国现行分类及联合国框架的对比,阐述了其主要特点及实施意义。     

Short-period Jupiter family comets after Stardust

The NASA Stardust mission has provided for laboratory study an extensive data set of cometary dust of known provenance (from comet 81P/Wild 2) yielding detailed insights into the composition of the comet. Combined with the results of data from other missions to short-period Jupiter family comets (JFC), this has greatly deepened the understanding of such objects. If depressions on the surface of comet 81P/Wild 2 are all taken as evidence of impact cratering, their number suggests a long occupancy in the outer region of the Solar System. The dust from comet 81P/Wild 2 has been shown to be heavily deficient in pre-Solar grains and rich in materials formed at high temperatures in the inner Solar System. Although it is too early to know if this is typical of JFC, it does argue for rapid and thorough mixing of materials in the disk on timescales related to comet formation, and may also suggest outward migration of small icy bodies after their formation. Thus, instead of providing mainly new knowledge of the pre-Solar materials expected to be rich in comets, Stardust and comet 81P/Wild 2 have instead focussed attention on large-scale transport processes during the critical period when cometary parent bodies were forming in the early Solar System.     

Application of horizontal-to-vertical (H/V) Fourier spectral ratio for analysis of site effect on rock (NEHRP-class B) sites in Taiwan

The frequency-dependent amplification for rock (NEHRP-class B) sites was studied using earthquake ground-motion database collected in Taiwan during implementation of the Taiwan Strong Motion Instrumentation Program. The database used includes several hundred records from earthquakes of M_L 4.0–7.3 occurred between 1993 and 2004. The characteristics of amplification were evaluated using the well-known technique of horizontal-to-vertical Fourier spectral ratio (H/V) of the S-wave phase [Lermo J, Chavez-Garcia FJ. Site effect evaluation using spectral ratios with only one station. Bull Seism Soc Am 1993;83:1574–94]. The study allows us to analyze peculiarities of rock sites amplification in Northern and Eastern Taiwan. It was suggested to divide the NEHRP-class B site amplification into four types based on frequency of maximum amplification and the shape of amplification function. The applicability of the technique was also checked for a few stiff and soft soil sites (NEHRP-classes D and E).     

伊犁河谷2001-2014年地表温度时空分异特征

地表温度是地表能量平衡、区域和全球尺度地表物理过程的一个重要因子。为了辨析中国西北干旱区“天山湿岛”——伊犁河谷的地表温度时空分异,采用趋势分析法和空间数据统计法,探讨了2001-2014年不同土地利用/覆盖类型下地表温度时空变化规律,分析地表温度的时空分异特征及原因。结果表明：（1） MODIS LST产品的精度（平均R²=0.90）能够满足伊犁河谷地表温度时空变化分析的要求;（2）空间上,地表温度呈现出中部高四周低的变化趋势,高温区面积约占总面积的41%,低温区面积约占总面积的23%;时间上,伊犁河谷平均地表温度的年际波动较大,以2013年、2006年、2007年和2008年尤为突出;地表温度的年内变化呈现出单峰型分布,地表温度高值集中在3-8月,最高值出现在7月;（3）不同土地利用/覆盖类型下年均地表温度分布的总体特征为建设用地最高,稀疏草地、旱地等次之,冰川/积雪最低;（4）伊犁河谷地表温度变化趋势呈严重减少、基本不变和轻微增加区域面积分别占5%、37%和26%,以基本不变和轻微增加为主。伊犁河谷地表温度时空变化不仅受大尺度气候变化影响,还受土地类型差异影响,两者共同构成了不同地理区域及景观的温场格局,绿色植被对地表温度时空分布具有重要的调节作用。     

The Leonid meteor storms of 1833 and 1966

The greatest Leonid meteor storms since the late eighteenth century are generally regarded as being those of 1833 and 1966. They were evidently due to dense meteoroid concentrations within the Leonid stream. At those times, the orbit of Comet 55P/Tempel–Tuttle was significantly nearer that of the Earth than at most perihelion returns, but still some tens of Earth radii away. Significantly reducing this miss distance can be critical for producing a storm. Evaluation of differential gravitational perturbations, comparing meteoroids with the comet, shows that, in 1833 and 1966 respectively, the Earth passed through meteoroid trails generated at the 1800 and 1899 returns.