Growth, Production, and a Partial Energy Budget for the Amphipod, Talorchestia capensis (Crustacea; Talitridae) in the Eastern Cape, South Africa

Abstract. .A population of Talorchestia capensis was sampled in dune slacks over the period of one year. Two hatching periods, one in March and one in September, were observed. Growth was rapid, the amphipods reaching a size of 8.4 mm standard length in 18 months. Maximum growth occurred in spring and minimum growth in winter. Annual mortality rates for summer- and winter-hatched individuals were low, 0.22-y“¹ and 0.16-y”¹. Average production for the summer classes was 7.2g-y?‘ (dry mass) and for the winter classes 2.9-y“¹, with a P/B ratio of 2.25-y”’. Production values peaked during autumn and summer. Abundance and biomass estimates showed maxima during summer and minima in early spring. Reproductive output was low, 0.1 kJ ? m^-2 y“¹, indicating that 7 % of the total production is used for reproduction and 93 % for somatic production. The assimilated energy flow through the population was estimated to be 16.3 kJ m?² y?‘ and consumption about 81.6 kJ m^-2 y^_’.     

南方鲇的排粪量及消化率同日粮水平、体重和温度的关系

于１９８８年２月－１９８９年２月测定了南方鲇幼鱼的排粪量，从而估算共消化率。结果表明，当水温为２５℃时，在日粮水平分别是体重的１％，２％，４％和达饱食的条件下，平均消化率分别为摄入食物能量的８０．３２％，８４．９４％，８８．４０％ｔ ８７．２７％；在平均初始体重分别为８．７２，２５．４３，４５．１６，７８．１８和１２７．５ｇ的实验组中，平均消化率分别为８６．５９％，８１．１５％，９０．３８％，８６     

Energetics of the Tsunami of 26 December 2004 in the Indian Ocean: A Brief Review

The energetics of the most destructive tsunami in historical time, and that of the under ocean earthquake that triggered this tsunami of 26 December 2004 in the Indian Ocean have been briefly reviewed. This latest tsunami has several other unique characteristics besides being one of the worst natural disasters in human history. It is the first truly global tsunami after modern seismographic and sea level monitoring networks have been put in place. It was the first tsunami on record detected by a satellite, even though at present, global satellite coverage of the oceans for real time tsunami detection is not adequate. Finally, the energy associated with the tsunami and the earthquake that triggered it is so large that speculation has been made about the normal modes of oscillation of the earth, that were triggered by the earthquake as well as some suggestions, that some of the earth's rotational characteristics may have temporarily changed to a discernible degree. Here, we briefly review the energetics of the tsunami and the earthquake that triggered it.     

基于Hoek-Brown准则的节理岩体能量参数估算

岩体变形和破坏可以看作能量耗散和释放的过程.由于节理岩体结构复杂且难以开展室内试验,因此无法通过试验直接求取其能量学参数.基于Hoek-Brown准则和岩石能量理论,提出了节理岩体在临界状态能量学参数的估算方法.针对含贯通节理(或层面)岩体,通过修正岩块单轴抗压强度以体现贯通节理的方向效应.采用PFC3D分别模拟小尺寸岩样(Φ50mm×100mm)和大尺寸岩体(Φ2m×2m)的三轴压缩试验,通过岩石三轴试验结果拟合岩石数值模拟的细观参数并应用于节理岩体的模拟.根据节理岩体模拟得到应力应变曲线和能量流,验证了Hoek-Brown准则对节理岩体能量参数估算的合理性.     

Effects of copper exposure on the scope for growth of the clam Ruditapes decussatus from southern Portugal

The clam Ruditapes decussatus L. was collected from Ria Formosa, Faro, southern Portugal, and exposed to a sublethal copper concentration of 0.01 mg l⁻¹ for 20 days. Physiological measurements, respiration rates, clearance rates and absorption efficiency, were undertaken initially and after 2, 5, 9, 14 and 20 days and used to calculate Scope for Growth. Copper accumulation rate was calculated through the analysis of copper in the tissues at the same sampling times. The experiment showed two phases. Initially, copper was rapidly accumulated (1.95 μg Cu g⁻¹ dw day⁻¹ in the first 48 h), clearance rates declined markedly (lowest value 13.5% of control) and respiration rates increased (116% of control), resulting in a rapid decline of Scope for Growth, which showed a negative value after 5 days. In the second phase, (from day 9 on), the rate of copper uptake declined to 0.55 μg Cu g⁻¹ day⁻¹ and physiological responses were more stable. After 20 days, copper concentration in the tissues was 38.4 μg Cu g⁻¹ dw (bioconcentration factor 3840). Clearance rates were 50% of control rates and respiration rates were still high, 145% of control rates. Therefore, Scope for Growth and performance of the clams was still greatly affected (ca. 23% of the control values), indicating that though animals partially recovered through detoxifying mechanisms, excess copper caused sustained impairment of physiological functions. This experiment confirms that the physiological energetics approach and the integrated Scope for Growth measurement is a sensitive methodology to detect deviations from normal performance and assess stress at environmental realistic copper concentrations.     

Energetics of lateral eddy diffusion/advection：Part Ⅳ. Energetics of diffusion/advection in sigma coordinates and other coordinates

Gravitational potential energy （GPE） source and sink due to stirring and cabbeling associated with sigma dif fusion/ advection is analyzed. It is shown that GPE source and sink is too big, and they are not closely linked to physical property distribution, such as temperature, salinity and velocity. Although the most frequently quoted advantage of sigma coordinate models are their capability of dealing with topography; the exces sive amount of GPE source and sink due to stirring and cabbeling associated with sigma diffusion/advec tion diagnosed from our analysis raises a very serious question whether the way lateral diffusion/advection simulated in the sigma coordinates model is physically acceptable. GPE source and sink in three coordinates is dramatically different in their magnitude and patterns. Overall, in terms of simulating lateral eddy diffu sion and advection isopycnal coordinates is the best choice and sigma coordinates is the worst. The physical reason of the excessive GPE source and sink in sigma coordinates is further explored in details. However, even in the isopycnal coordinates, simulation based on the Eulerian coordinates can be contaminated by the numerical errors associated with the advection terms.     

内蒙古中西部地区降雹天气预报方法

首先从大气能量学的观点出发,阐述了有利于冰雹产生的几个因子和动力条件;尔后通过对内蒙古中西部地区１９８０￣１９８７年降雹的８４次个例的计算分析,获得了适于内蒙古中西部冰雹天气的预报指标,在业务预报中收到一定效果。     

扰动位能理论及其应用——扰动位能的概念、表达及其时空结构

针对局地环流能量转换问题,该工作系列讨论扰动位能理论及其应用.此文是第一篇,提出了扰动位能的新概念,将其分解为大气扰动位能(简称扰动位能)和表面扰动位能两个部分,给出了扰动位能各阶矩项的数学表达形式,结合资料指出二阶以上的扰动位能高阶矩项相对于其一阶矩项和二阶矩项来说是小量,可忽略,并指出扰动位能二阶矩项的全球平均恰好等于传统的有效位能,但两者在物理意义上明显不同.结合NCEP/NCAR再分析资料,研究了扰动位能的时空结构以及与大气动能之间的联系.扰动位能一阶矩项在热带地区为正、高纬度地区为负; 二阶矩项在热带和高纬度地区出现极大值,在副热带及中纬度地区出现极小值,即在南北方向上呈现三峰二谷的特征; 在局地上,由于一阶矩项在数值上较二阶矩项绝对占优,因此,扰动位能的分布与其一阶矩项的情形相似.在垂直方向上,扰动位能主要集中在对流层下层,其数值随高度的增加而迅速减少,在50 hPa以上均可以忽略不计.扰动位能有明显的季节变化,其在高纬度地区在冬半球比夏半球大很多; 南、北半球平均的扰动位能一阶矩项季节变化的幅度约是相应二阶矩项的二十倍.随着季节变化扰动位能定常波的槽脊在北半球有显著的东西方向移动,而在南半球则只表现为振幅上的增减.分析表明,从区域或局地尺度上大气动能的季节变化与扰动位能一阶矩项的关系密切,二者呈显著反向变化关系,而与二阶矩项的关系不确定; 但在全球或半球尺度上,大气动能与扰动位能二阶矩项的比率随季节基本保持不变,约是20%.此外,对大气总动能时空结构的分析也得到了与前人不同的新结果.关于利用此文提出的概念和理论对局地环流能量收支的分析、表面扰动位能的作用以及它们在大气环流变化研究中的应用,将在以后的文章中给出.     

Experimental Study of Geoneutrinos with KamLAND

The Kamioka liquid scintillator antineutrino detector (KamLAND), which consists of 1000 tones of ultra-pure liquid scintillator surrounded by 1879 photo-multiplier tubes (PMT), is the first detector sensitive enough to detect geoneutrinos. Earth models suggest that KamLAND observes geoneutrinos at a rate of 30 events/10³²-protons/year from the ²³⁸U decay chain, and 8 events/10³²-protons/year from the ²³²Th decay chain. With 7.09×10³¹ proton-years of detector exposure and detection efficiency of 0.687 ± 0.007, the ‘rate-only’ analysis gives geoneutrino candidates. Assuming a Th/U mass concentration ratio of 3.9, the ‘rate + shape’ analysis gives the 90% confidence interval for the total number of geoneutrinos detected to be from 4.5 to 54.2. This result is consistent with predictions from the Earth models. The 99% C.L. upper limit is set at 1.45×10⁻³¹ events per target proton per year, which is 3.8 times higher than the central value of the model prediction that gives 16 TW of radiogenic heat production from ²³⁸U and ²³²Th. Although the present data have limited statistical power, they provide by direct means an upper limit for the Earth’s radiogenic heat of U and Th. Sanshiro Enomoto (on behalf of the KamLAND Collaboration)