博斯腾湖水质现状(2010-2011年)及近50年来演变趋势

博斯腾湖(简称博湖)6个采样点周年(2010年6月-2011年6月)水质调查分析表明,博湖水质空间差异明显,但不同样点水质月变化无一致趋势.大湖区西北角水域水质最差;开都河入湖处水质月变化幅度大,水质相对较好;中东部水域水质处于中间水平.小湖区喇嘛湖水质最好,介于Ⅰ-Ⅲ级之间;北闸附近的湖沼湿地,水质差,多为Ⅴ类和劣Ⅴ...     

Relationship between regional stress field variation and earthquake activities from GPS data

IntroductionWith the development of science and technology, especially with the development of spatial geodetic technology (Tralli, Timothy, 1988), it is possible to precisely obtain the continuous geodetic data on the earth surface by Global Positioning System (GPS) observation. The spatial geodetic technology can be used to observe the deformation response on the earth surface caused by the stress field variation, and some deformation and movement feature in the earth crust during the pro…     

Variation characteristics of heavy metals and nutrients in the core sediments of Taihu Lake and their pollution history

The sedimentary environment change, trophic evolution and heavy metals pollution history of the northern Taihu Lake in the last 100 years are studied according to the sedimentary geo-chemical proxies of the core sediments, such as grain size, nutrients, heavy metals, diatom, etc. The nutrients in the sediments depended mainly on the lake internal circulation and the heavy metals were from natural geogenic sources before the 1920s, which were not influenced by human activities generally, and grain size was one of the key factors influencing heavy metals content in the sediments. The alternation of manner and strength of human activities in Taihu Lake catchment before and after the 1920s made the lake sediments coarser, and hence heavy metals and TP content decreased contrasted with that before the 1920s. TP content in sediments and water increased from the 1950s to late 1970s due to anthropogenic pollutants discharge, and the lake belonging to mesotrophic state. TN and TOC content and C/N ratio increased due to the increasing external pollutants into Taihu Lake by human activities, TP content also increased obviously in water and sediments, and the diatom association was dominated by eutrophic species since the late 1970s, indicating the eutrophication state of Taihu Lake in this period. Meanwhile the increasing in heavy metals content, such as Cu, Mn, Ni, Pb and Zn, and their proportion of valid fractions in the sediments indicates that they all result from human pollutants since the late 1970s. The heavy metals in the surface sediments have certain potential biological toxicity due to the higher SEM/AVS ratio.     

浑河断裂带(抚顺段)近期活动性与地质灾害的关系

通过对浑河断裂带（抚顺段）的地质调查、人工地震勘查、断裂绝对年龄测定、跨断裂形变测量等资料的综合分析与研究,讨论了断裂构造的近期活动特征,并据此认为浑河断裂自晚更新世以来若非人类工程活动扰动是没有活动的,现今的断裂活化效应是由于大量的人类采煤活动造成的。由于断裂的活化效应破坏了抚顺煤田及其周围区域原始构造应力场的平衡状态,为达到新的平衡必然导致应力的重新集中与释放,在此过程中伴随产生了抚顺煤田广泛发育的滑坡、地面沉陷、矿震、地裂缝等地质灾害。     

Five-year bio-monitoring of aquatic ecosystems near Artigas Antarctic Scientific Base,King George Island

Fildes Peninsula, in King George Island, Antarctica, has a great concentration of international facilities, and it has clearly been affected by human activities. The objective of this 5-year study was ...     

Changes in run‐off and sediment load in the three parts of the Yellow River basin,in response to climate change and human activities

Hydrological regimes in the Yellow River have changed significantly because of climate change and intensive human interventions. These changes present severe challenges to water resource utilization and ecological development. Variation of run‐off, suspended sediment load (SSL), and eight precipitation indices (P1: 0–12 mm·day^?1, P12: 12–25 mm·day^?1, P25: 25–50 mm·day^?1, P50: P ≥ 50 mm·day^?1 and corresponding rainfall day: Pd1, Pd12, Pd25, Pd50 day year^?1) in three critical parts of the Yellow River basin (source region: SRYRB, upper reaches: URYRB, middle reaches: MRYRB) were investigated for the period from 1960 to 2015. The results show that run‐off and SSL significantly decreased (P < 0.01) in the URYRB and the MRYRB, whereas their decline in the SRYRB was insignificant (P > 0.05). Moreover, run‐off in the URYRB had one change point in 1987, and SSL in the URYRB as well as run‐off and SSL in the MRYRB had two change points (in the 1970s and the 1990s). Over the same period, only Pd1 and Pd12 in the SRYRB showed significant increasing trends, and an abrupt change appeared in 1981. The optimal precipitation indices for assessing the effects of precipitation on run‐off and SSL in the URYRB and MRYRB were Pd50 and P12, respectively. A double‐mass curve analysis showed that precipitation and human activities contributed to approximately 20% and 80% of the reduction in run‐off, respectively, for both the SRYRB and the MRYRB. However, the contribution rate of precipitation and human activities on SSL reduction was approximately 40% and 60% in the URYRB and 5% and 95% in the MRYRB, respectively. Human activities, primarily soil and water conservation measures and water extraction (diversion), were the main factors (>50%) that reduced the run‐off. However, the dominant driving factors for SSL reduction were soil and water conservation measures and reservoir interception, for which the contribution rate was higher than 70% in the MRYRB. This work strengthens the understanding of hydrological responses to precipitation change and provides a useful reference for regional water resource utilization.     

Effect of volatiles erupted from Mesozoic and Cenozoic volcanic activities on paleo-environmental changes in China

Based on the determination of composition of volcanic volatiles and petrologic estimation of the total mass of volatiles erupted, we showed important advances in the study of the impact of Mesozoic and Cenozoic volcanic activities on paleo-environmental changes in China. The volcanic activities include western Liaoning and Zhangjiakou Mesozoic intermediate-acidic explosive eruptions, southern Tibet and Shanwang Cenozoic volcanism, and Mt. Changbai volcanic eruption around one thousand years ago. The paper predominantly discusses the earth’s surface temperature changes, ozone depletion, acidic rain formation and mass mortalities of vertebrate induced by the Mesozoic and Cenozoic volcanism in China. __________ Translated from Bulletin of Mineralogy, Petrology and Geochemistry, 2007, 26(4): 319–322 [译自: 矿物岩石地球化学通报]     

Historical fluxes of metal and metalloids in an aquatic ecosystem affected by land-use change and mining activities in northwestern Mexico

Freshwater reservoirs are essential owing because of their ecological, economic, and social importance. They are particularly vulnerable to contamination, as of metal and metalloids, derived from anthropogenic activities like mining. The temporal variations in trace element concentrations (arsenic (As), mercury (Hg), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)), enrichment, fluxes, and possible sources were evaluated by studying two sediment cores from the La Angostura (ANG) Reservoir (northwest Mexico), using ²¹⁰Pb geochronology. The enrichment factors showed from null to minor enrichment for most elements, but moderate to severe enrichment of mercury (Hg). Most trace element concentrations had a detrital origin, and notable Hg concentration increases since the past decade were associated with severe drought periods, likely resulting from wildfires. The observed sediment concentrations of As and Hg can cause adverse effects on biota in the ecosystem since they are above the probable effect level (PEL). Development of strategies for metal attenuation in this reservoir is recommended and metals should be controlled until specific ecotoxicological studies are performed.     

The role of anthropogenic activities in karst spring discharge volatility

The traditional hydrological time series methods tend to focus on the mean of whichever variable is analysed but neglect its time‐varying variance (i.e. assuming the variance remains constant). The variances of hydrological time series vary with time under anthropogenic influence. There is evidence that extensive well drilling and groundwater pumping can intercept groundwater run‐off and consequently induce spring discharge volatility or variance varying with time (i.e. heteroskedasticity). To investigate the time‐varying variance or heteroskedasticity of spring discharge, this paper presents a seasonal autoregressive integrated moving average with general autoregressive conditional heteroskedasticity (SARIMA‐GARCH) model, whose the SARIMA model is used to estimate the mean of hydrological time series, and the GARCH model estimates its time‐varying variance. The SARIMA‐GARCH model was then applied to the Xin'an Springs Basin, China, where extensive groundwater development has occurred since 1978 (e.g. the average annual groundwater pumping rates were less than 0.20 m³/s in the 1970s, reached 1.20 m³/s at the end of the 1980s, surpassed 2.0 m³/s in the 1990s and exceeded 3.0 m³/s by 2007). To identify whether human activities or natural stressors caused the heteroskedasticity of Xin'an Springs discharge, we segmented the spring discharge sequence into two periods: a predevelopment stage (i.e. 1956–1977) and a developed stage (i.e. 1978–2012), and set up the SARIMA‐GARCH model for the two stages, respectively. By comparing the models, we detected the role of human activities in spring discharge volatility. The results showed that human activities caused the heteroskedasticity of the Xin'an Spring discharge. The predicted Xin'an Springs discharge by the SARIMA‐GARCH model showed that the mean monthly spring discharge is predicted to continue to decline to 0.93 m³/s in 2013, 0.67 m³/s in 2014 and 0.73 m³/s in 2015. Copyright © 2014 John Wiley & Sons, Ltd.     

珠江河网横向汊道水面线演变过程及原因探讨 ——以东平水道为例

基于1960-2016年东平水道三水、紫洞、澜石、浮标厂月均潮差、余水位数据及三水、马口站月均流量数据,以1993年三水-马口分流比突变为切入口,探讨余水位坡度及潮波衰减率等径-潮动力改变下,东平水道水面线与余水位曲率的时空演变特征及其影响因素.结果表明:东平水道在1993年三水分流比剧增之后,1)余水位坡度或潮波衰减...