Relating abundance of purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea

The distribution pattern of purpleback flying squid and the relationship between its abundance and environmental variables in the south-eastern Arabian Sea were analysed using a geographical information system (GIS) and a generalised additive model (GAM). Highest abundances were observed during December and January within 10 and 13°N and 71 and 72°E around the Lakshadweep Islands. The mean abundance in the area was 4.21 tonnes/km² and the maximum sustainable yield (MSY) was estimated as 0.63 million tonnes. GAM indicated that very high squid abundance was associated with low values of dissolved oxygen (6.01–6.27 mg/L), sea surface temperature (28.03–28.62°C), pH (7.75–8.56), salinity (30.42–34.48 psu), chlorophyll-a (0.4–0.6 mg/m³), zooplankton biomass (0.23–0.64 mL/m³), and shallow 20°C isotherm (101.2–134.7 m) and mixed layer depth (17.8–29.8 m). As a carnivore from paralarval stages, S. oualaniensis depends on secondary and tertiary production to sustain its population for which primary production is used up. In the tropical Arabian Sea where temperature differences are not so pronounced, S. oualaniensis distribution was found to be related to a low but very narrow sea surface temperature (SST) band. There is sufficient fishable biomass in the area to possibly launch a new targeted oceanic squid fishery from the western seaboard of India.     

Effect of tropical monsoon on fishery abundance of Indian squid (Uroteuthis (Photololigo) duvaucelii)

Indian squid, Uroteuthis (Photololigo) duvaucelii (Loliginidae) constitute an important component of the inshore cephalopod fisheries along the eastern Arabian Sea. Local environmental variation plays an important role in species–environment interactions in neritic squids, which inhabit nearshore/coastal waters. Such ‘active’ and ‘passive’ responses of squids to environmental changes is crucial in understanding their relationships and influence on the biological processes, distribution and abundance of the fast-growing short-lived coastal loliginids. The empirical relationship between squid abundance and the variability in rainfall and sea surface temperature (SST) were explored in a tropical monsoon fishery. Monthly catch rates (catch per fishing hour) of squids in commercial trawl during 1987–2009 were used as the abundance index. Linear regression models with ARIMA errors were fitted with catch per unit hour time series as dependent variable and rainfall and SST as exogenous variables. While rainfall was observed to have a negative effect on squid abundance, the SST recorded a positive impact. ARIMA models provided satisfactory fit to observed data and forecast of 22 months. Given that the squid life-cycle is a function of their environment, this result is relevant in forecasting squid biomass for the management of tropical monsoon fisheries.     

贫金属星HD 122956的中子俘获元素丰度

根据贫金属星ＨＤ１２２９５６的中子俘获元素的观测丰度,利用贫金属星中子俘获元素丰度的计算模型,采用最小二乘法精确地确定了三种不同的中子俘获过程对该贫金属星中子俘获元素丰度的贡献,从理论上预言了贫金属星ＨＤ１２２９５６的中子俘获元素的丰度,并给出了计算结果与预测结果的比较。     

南京灵谷寺森林种多度结构变化的研究

利用灵谷寺森林１９５１年、１９８１年和１９１年的数据资料,以种数、个体数、频度为广义多度,分别探讨了种数、个体数、个体数－种序的分布结构变化,并据此分析了该群落近４０年来的动态行为。种数－个体数分布符合对数正态分布和负二项分布,个体数－种序和频度－种序的分布均符合对数级数分布,灵谷寺森林目前仍处于演替的初期,其物种数、个体数、种群空间分布格局均表现出较大的波动。演替以波浪的形式发展,演替过程中对演     

LC-MS-MS快速筛查富硒植物四种有机硒方法应用研究

应用液相色谱串联质谱法(LC-MS-MS)鉴定富硒植物中四种有机含硒化合物,验证该方法的应用价值,了解这些富硒植物是否含有新的硒种类。植物样品用沸水提取,以甲醇-0.1%七氟丁酸水溶液(30:70)为流动相,滤液经WatersSymmetryC18(50mm×3.9mm,5μm)分离,经在线电喷雾离子源(ESI)正离子化后,采用多反应离子监测方式(MRM)测定含硒化合物。结果在4种富硒植物中检测到一到两种与标准品相同的含硒化合物,其它5种富硒植物中没有发现与标准品相同的有机硒。证明LC/MS/MS能有效、快速、准确筛查已有标准品的植物含硒化合物,在富硒植物中有望进一步获得新型含硒化合物。     

关于中国宏观区域格局划分的思考

缩小地区差距,促进地区的协调发展,是区域划分面临的重大挑战。在区划中应认真贯彻中央精神,积极进行产业整合和集聚,勇于打破行政区划,培育新的经济区划的合作机制。     

基于遥感更新的省级生物丰度归一化系数研究——以湖北省为例

在中国资源环境数据库三期数据支撑下,利用2005年TM影像对湖北省土地利用信息的数据遥感更新,计算出1995年和2000年两个时期的湖北省省级生物丰度归一化系数,并对不同尺度的归一化系数进行分析和研究.绘制出1995年、2000年湖北省生物丰度等级图,清晰反映出湖北省生物丰度的区域分异规律,为我国生态环境影响评价研究提供技术支持.     

贵州北部区域残坡积石灰土质量评价

了解黔北高原残坡积石灰土元素的丰贫程度、超标危害现状及潜在生态危害状况,为黔北区域农业的持续发展和长远规划提供依据。以仁怀,桐梓,习水,赤水,古蔺等地岩溶区不同时代的石灰土为样体,进行调查,采样,检测,分析。结果显示:石灰土元素中K、Si、P、Pb、Ca、Na丰度均值为0.2~1.0;P2石灰土P综值为2.53,T2、P1、∈2-3为1.07~1.97,超标元素为Ni;石灰土RI值为30.42~54.28。分析认为:K、Si、P、Pb、Ca、Na为贫乏级元素;Ni为超标元素,P2石灰土为中度超标,T2、P1、∈2-3为轻度超标;石灰土潜在生态环境好。     

中国煤中汞的含量、分布与赋存状态研究

在测试分析中国皖北矿区6个煤矿81个煤样品中汞含量的基础上,结合国内外文献资料中报道的1 712个中国煤样品中汞的数据,对中国煤中汞的含量、分布、赋存状态及燃煤引起的汞的环境污染进行了分析和探讨。通过研究得出:中国煤中汞的平均含量为0.20 mg/kg,高于世界煤中汞的平均值(0.10 mg/kg),接近美国煤中汞的平均值(0.17 mg/kg);由于沉积环境及成煤过程中各种地质因素的综合影响,汞在中国不同地区、不同成煤时代以及不同变质程度煤中的含量差异较大;高硫煤中的汞与硫化物关系密切,主要赋存在黄铁矿中;硫化物结合态和有机结合态是低硫煤中汞的主要存在形态;岩浆活动对煤中汞的含量分布与赋存状态有明显影响;煤中汞的赋存状态与煤中汞的释放、毒性有着重要的关系,中国巨大的煤炭消耗量,已引起大量的汞排放,控制燃煤过程中汞的排放是今后环境保护的重要内容之一。     

两种代表性富硒植物硒在实验性高脂血症大鼠组织累积分布研究

对比研究富硒大蒜和富硒绿羽中的植物硒在实验性高脂血症大鼠主要组织的累积分布情况,为安全利用富硒植物硒资源提供理论依据.采用高脂膳食诱导大鼠高脂血症,分别在大鼠饲喂高脂饲料同时(预防组)和高脂血症形成以后(治疗组)以灌胃的方式给予富硒植物悬浊液,实验期3个月,实验结束后宰杀大鼠,测定大鼠肝、肾、脾、红细胞和血浆含硒量.总体来看,富硒绿羽组大鼠肝脏和肾脏含硒量显著高于富硒大蒜组,富硒绿羽组大鼠脾脏和红细胞硒水平低于富硒大蒜组;摄入不同植物硒的治疗组和预防组在组织硒累积幅度和分布上有一些变化.硒在不同组织内分布受摄入硒形态、给药时间和给药期的影响,富硒大蒜比富硒绿羽具有更高的安全性.