秦皇岛山羊寨动物群及其生存环境的研究

1981年，笔者在泰皇岛市抚宁县山羊寨村小南山发现大量动物化石，经鉴定共有32种动物，其中绝灭种7个，时代为新生代第四纪中更新世，绝对年龄为（18±2）万年至（20±2）万年，相当于北京周口店动物群后期。研究发现：其生活在低山丘陵及其河谷；当时的气候是温和湿润的温带气候，但已向凉干转化；植被为温带落叶阔叶林。     

Leaching,mobility and persistence of tebufenozide in columns packed with forest litter and soil

Abstract

Leaching, downward mobility and persistence of tebufenozide was investigated under laboratory conditions in columns packed with forest litter and soil, after fortification with the analytical grade material (purity > 99.6%) and with two commercial formulations, RH‐5992 2F (aqueous flowable) and RH‐5992 ES (emulsion suspension). Two types of litter and soil were used: one type with relatively high amounts of sand and the other with high amounts of clay.

The concentrations eluted in the leachates were lower when the analytical material (dissolved in acetone) was used for fortification, than when the two formulations (diluted with water) were used. The amount leached was higher for RH‐5992 2F than for RH‐5992 ES. The type of substrate, i.e., sandy or clay type, had only marginal influence on the amounts eluted in the leachates. Downward movement of tebufenozide from the top 2‐cm layer to the untreated middle and bottom layers (3‐cm segments) was consistently lower when the analytical material was used for fortification, than when the two formulations were used. Downward movement was higher for RH‐5992 2F than for RH‐5992 ES. Persistence of tebufenozide in substrates, maintained under submerged conditions for 70 days after leaching, indicated an initial 2‐week lag period prior to the onset of degradation. Formulation‐related differences were observed in the half‐life (DT₅₀) values. When the analytical material was used for fortification, the DT₅₀ ranged from ca 54 to 59 d. However, when the formulations were used for fortification, the DT₅₀ showed a higher range, i.e., from ca 62 to 67 d for RH‐5992 2F and ca 70 to 80 d for RH‐5992 ES. Formulation ingredients appear to have caused enhanced adsorption of tebufenozide onto the substrates, thus delaying degradation.     

Mercury in European Blushers,Amanita rubescens,mushrooms and topsoils: Bioconcentration potential and intake assessment

Total mercury content has been determined in fruiting bodies of European Blushers and topsoils collected from 11 sites across Poland in 2006-2008. Mercury analysis was carried out using a validated analytical method and cold-vapour atomic absorption (CV-AAS). The European Blusher effectively accumulated mercury in fruiting bodies. The mean values of total mercury in caps of European Blushers from background (uncontaminated) areas were from 0.22 to 1.0 (0.067-3.2) and in stipes from 0.16 to 0.65 (0.071-2.7) μg/g dry weight. In topsoil beneath to fruiting bodies, the median Hg concentration at 10 sites in Northern Poland varied between 0.030 and 0.072 (0.0096–0.19) μg/g dw, and in one site in Southern Poland was 0.20 (0.079–0.34) μg/g dw. Data on Hg in European Blushers from different countries were reviewed. The mean concentrations of total Hg in caps of European Blushers from two “pristine” sites in northern part of Poland were ～1.0 μg/g dw. A meal made with 300–500 g of fresh caps of European Blushers collected at such sites (assuming 90% water content in caps) can result in Hg intake of 0.0003–0.0005 mg Hg/kg bm (assuming a 60 kg bm), which is a dose equipotent to a new provisional tolerable weekly intake (PTWI) value set for inorganic Hg.     

Inorganic elemental concentrations in birch bolete mushroom (Leccinum scabrum) and top soil: contamination profiles,bioconcentation and annual variations

Abstract

Analysis of inorganic and organic contaminants in foodstuffs aids in understanding the human exposure to these compounds via consumption. In this study, an edible mushroom species (Leccinum scabrum) and top soil samples were analysed for essential and toxic substances including phosphorus and inorganic elements over a period of three fruiting seasons. Analysis of silver (Ag), aluminium (Al), barium (Ba), calcium (Ca), cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), mercury (Hg), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), phosphorus (P), lead (Pb), rubidium (Rb), strontium (Sr) and zinc (Zn) in mushrooms and topsoil were performed using inductively coupled plasma optical emission spectroscopy (ICP-OES) with ultrasonic cross flow nebulizer. Total mercury was determined by cold-vapour atomic absorption spectroscopy (CV-AAS). The results exhibited wide variation in concentrations of metals between soil and mushroom (cap and stipes) during three fruiting seasons. Positive bioconcentration factors (BFCs) indicate on bioaccumulation of several metals including, Cd, Cu, Hg, K, Mg, Na, P, Rb and Zn in caps and stipes of fruitbodies of this mushroom, while other metals such as Al, Ba, Ca, Co, Fe, Mn, Ni, Pb and Sr were not exhibiting significant positive BFCs. Over a period studied, the caps were characterised by different (p?<?0.05) concentrations of Al, Co, Cu, Hg, Mn, Ni, P, Pb and Sr. Contamination profiles, temporal fluctuations, BCFs should be taken into consideration when assessing the nutritional value of this mushroom.     

Effects of Exurban Development and Temperature on Bird Species in the Southern Appalachians

Land‐use dynamics and climatic gradients have large effects on many terrestrial systems. Exurban development, one of the fastest growing forms of land use in the United States, may affect wildlife through habitat fragmentation and building presence may alter habitat quality. We studied the effects of residential development and temperature gradients on bird species occurrence at 140 study sites in the southern Appalachian Mountains (North Carolina, U.S.A.) that varied with respect to building density and elevation. We used occupancy models to determine 36 bird species’ associations with building density, forest canopy cover, average daily mean temperature, and an interaction between building density and mean temperature. Responses varied with habitat requirement, breeding range, and migration distance. Building density and mean temperature were both included in the top occupancy models for 19 of 36 species and a building density by temperature interaction was included in models for 8 bird species. As exurban development expands in the southern Appalachians, interior forest species and Neotropical migrants are likely to decline, but shrubland or edge species are not likely to benefit. Overall, effects of building density were greater than those of forest canopy cover. Exurban development had a greater effect on birds at high elevations due to a greater abundance of sensitive forest‐interior species and Neotropical migrants. A warming climate may exacerbate these negative effects. Efectos del Desarrollo Exurbano y de la Temperatura sobre Especies de Aves en las Apalaches del Sur     

Lichen Conservation in Heavily Managed Boreal Forests

Lichens are an important component of the boreal forest, where they are long lived, tend to accumulate in older stands, and are a major food source for the threatened woodland caribou (Rangifer tarandus caribou). To be fully sustainable, silvicultural practices in the boreal forest must include the conservation of ecological integrity. Dominant forest management practices, however, have short‐term negative effects on lichen diversity, particularly the application of herbicides. To better understand the long‐term effects of forest management, we examined lichen regeneration in 35 mixed black spruce (Picea mariana) and jack pine (Pinus banksiana) forest stands across northern Ontario to determine recovery following logging and postharvest silvicultural practices. Our forest stands were 25–40 years old and had undergone 3 common sivilcultural treatments that included harvested and planted; harvested, planted, and treated with N‐[phosphonomethyl] glycine (glyphosate); and harvested, planted, and treated with 2,4‐dichlorophenoxyacetic acid (2,4‐D). Forest stands with herbicide treatments had lower lichen biomass and higher beta and gamma diversity than planted stands that were not treated chemically or control stands. In northwestern Ontario, planted stands that were not treated chemically had significantly greater (p < 0.05) alpha diversity than stands treated with herbicides or control stands. Our results show that common silvicultural practices do not emulate natural disturbances caused by wildfires in the boreal forest for the lichen community. We suggest a reduction in the amount of chemical application be considered in areas where lichen biomass is likely to be high and where the recovery of woodland caribou is an objective. Conservación de Líquenes en Bosques Boreales Manejados Intensivamente     

基于《电力设施抗震设计规范》的地震动随机模型参数研究

依据《电力设施抗震设计规范》(GB50260-96)中的设计反应谱,对随机地震动功率谱参数的取值进行了具体研究。首先,采用时间包络函数考虑地震的非平稳特性,给出了地震动持时的取值;然后,根据加速度峰值等效原则,迭代计算得到地面的加速度功率谱密度曲线;最后,选定Clough-Penzien修正过滤白噪声模型作为拟合函数,通过非线性拟合技术拟合了与《规范》中的地震烈度、场地类别相对应的谱参数。研究结果表明,Clough-Penzien修正过滤白噪声模型能较好地拟合其曲线形状。本文给出了相对于规范中的地面加速度功率谱参数值,可供这种模型作为地震地面运动输入时选用。     

高森林火险天气形势及其前期气候特征与预报

利用1980-2006年27年间黑龙江省林区发生的37次特大森林火灾资料,针对高空500hPa温压场的结构,将着火前3天短期时段内的天气形势分为4类8型,在此基础上对相对湿度与气温等因子的变化进行了分析,并对高火险日数及前期气候与大气环流特征进行了预报.     

武宁县森林扰动及驱动因子分析

森林扰动是影响陆地生态系统的重要因子,也是影响全球碳循环的重要因素.以江西省武宁县为例,利用1986-2011年14景Landsat TM/ETM+遥感影像,通过扰动指数(disturbance index,DI)时间序列轨迹分析提取森林扰动信息,并引入经验正交函数(empirical orthogonal function,EOF)分解方法定量分析了森林扰动的时空变化规律,利用GIS深入分析了自然和社会驱动因子影响.结果表明,武宁县森林扰动在1986-1998年较强,扰动面积以1992年为最大,以地区性扰动为主;2000年以后则趋于平缓,扰动以砍伐和森林火灾为主;在空间上,扰动主要发生在近道路、低海拔、低坡度和近水地区,并受地形和交通的制约,城镇化逐渐成为该地区森林扰动的一个不可忽略的驱动因子.     

关于随机振动试验

为了更好地进行随机振动试验，本文叙述了随机振动试验中需要的一些基本技术方法。