不同电子受体及盐分输入对河口湿地土壤甲烷产生潜力的影响

对闽江河口芦苇(Phragmites australis)湿地土壤甲烷产生潜力及电子受体(硝酸盐,三价铁和硫酸盐)及盐分(氯化钠)输入对其的影响进行了厌氧培养实验及测定。结果表明,芦苇湿地土壤甲烷产生潜力范围是0.0202~0.0871 μg · g^-1 · d^-1,0~10 cm土壤甲烷产生潜力最大;电子受体及盐分的输入对土壤甲烷产生潜力具有抑制作用,3种电子受体对甲烷产生潜力抑制程度从大到小为硝酸盐>三价铁>硫酸盐,不同浓度硝酸盐与三价铁添加后甲烷产生潜力与对照土壤差异显著(P<0.05),而硫酸盐与盐分的添加抑制作用不显著,对于每一种电子受体及盐分其不同浓度处理对甲烷产生潜力的影响差异也不明显(P>0.05)。     

旅游企业环境意识的调查研究——以内蒙古草原旅游发展为例

根据环境意识结构,设计了旅游企业环境意识调查问卷,其主要的指标体系包括：旅游环境知识水平、旅游环境态度、旅游环境评价和旅游环境行为四个方面。对指标体系各部分之间以及每一指标部分的每一题目之间的相对重要性进行权重的确定,而且对各部分的每道题目的各个选项予以赋分数。基于权重和赋分,结合调查问卷的实际情况,设计了指标体系各部分评价模型和环境意识总体评价模型,以此来计算草原旅游发展中旅游企业环境意识水平的综合得分。经过分析得出,旅游企业环境意识模式是“环境行为制约型”模式,从总体来看,环境知识不是制约旅游旅游企业环境意识水平的关键问题,环境评价和环境态度也不是主导因素,而旅游企业的环境行为是至为重要的因素。     

中国工业经济转型过程中能源消费与碳排放时空特征研究

就近30 a来中国工业经济转型过程中能源消费与碳排放的关联变化进行了分析,结果表明,工业部门能源消费的持续增长是中国能源消费总量增长与碳排放量增长的主要驱动因子;工业碳排放总量增长快速,但工业碳排放密集度持续降低;工业部门中制造业碳排放量最大,平均约占工业部门碳排放总量的60%,降低传统制造业能源消费、提高能源利用效率是推动节能减排政策实施和地方行动响应的关键环节;地区工业能源高消费地区集中分布于中国环渤海地区,能源较高消费地区主要集中于中国中部地区和东部经济发达地区,能源中等消费地区主要集中于中国西部地区,而能源低消费地区集中于西部经济落后地区;中国区域工业碳排放总量除受到本地工业能源消费量的直接影响外,还受到各地能源消费结构的影响,值得注意的是,较高碳排放地区空间布局趋于"孤岛"分布格局,低碳排放地区的数量也逐渐增加。     

基于企业微观视角的城市区域生产网络空间组织研究——以粤东城镇群服装生产为例

城镇间的产业联系是城市(镇)群研究的重要内容之一,然而传统研究多使用宏观统计数据,缺少从企业微观层面对城市产业联系的研究,难以清晰刻画城镇之间复杂的产业联系。随着社会网络分析方法在多学科的运用,城镇群生产网络空间组织的可视化表达和定量分析成为可能。选择粤东城镇群的服装生产为案例,通过深度访谈构建企业关系数据库,运用社会网络分析软件直观模拟城镇群区域服装生产网络,探讨城镇空间结构与生产网络之间的内在联系。结果发现:① 粤东城镇群区域内形成了复杂的生产网络,从网络结构上看,大部分节点存在于一个大的网络中,建立直接或间接联系,仅有个别点或小集团孤立在外,网络中各企业的度数中心度和中间中心度存在较大差别;② 从网络空间上看,汕头同潮州和普宁都存在密切联系,但潮州和普宁之间缺少联系,而汕尾孤立于汕潮揭之外;③ 各等级城镇在粤东城镇群区域服装生产网络中发挥了不同的作用,城镇的专业化与区域的多样化共同推动服装生产的网络化。为城镇群内部经济联系研究提供了新的思路与方法,对城镇群网络化建设具有参考价值。     

地球系统模式中植被净初级生产力百年尺度时空变化及其与气候的关系

利用6个地球系统模式模拟的植被净初级生产力（NPP）对1901～2005年NPP时空变化进行了研究,并结合气候因子分析了NPP的变化与气温和降水的关系。结果表明:（1）近百年来全球NPP呈现上升趋势,模式集合平均的趋势系数为0.88,通过了99.9%的信度检验;北半球的趋势比南半球明显。（3）近百年来800 g(C) m-2 a-1以上的NPP高值区主要分布在南美洲赤道地区、非洲赤道地区、中南半岛和印度尼西亚一带的热带雨林区;低值区主要分布在北半球高纬度地区、非洲北部地区、亚洲大陆干旱半干旱区以及青藏高原西北部地区。（3）全球NPP与气温百年演变在大部分地区主要为正相关关系,仅在赤道附近的南美洲、非洲以及印度地区为负相关关系,主要由于这些地区辐射是NPP的限制因子。全球NPP与降水的百年变化在大部分地区也主要是正相关关系,在非洲北部到西亚中亚的干旱半干旱地区为负相关关系。（4）6个地球系统模式在全球21个区域的大部分地区的NPP和气温降水的变化关系较为一致,西非地区不同模式变化不一致,NPP模拟的不确定性较大,其次是地中海地区。（5）东亚地区NPP与气候的百年演变同步并且相关性高,反映了强烈的植被大气相互作用过程。     

Two new species of hatschekia (copepoda,dichelesthiidae) from New Zealand waters

Two new species of Hatschekia Poche, 1901 are described from New Zealand specimens of Allomycterus jaculiferus (Cuvier, 1818) and Lepidopus caudatus (Euthrasen, 1878) respectively. Comment is made on the need for revision within the genus Hatschekia.     

Further records of Craspedacusta sowerbyi lankester in north island lakes (note)

Collections of mature medusae from Lake Rotoiti proved all to be male and provide further evidence that the origin of the species in New Zealand was from a very limited introduction.     

Calibrations to estimate absolute numbers of New Zealand fur seal (Arctocephalus forsteri) pups from direct counts

Annual direct counts of seal pups can indicate long‐term trends in population size, but mark‐recapture estimates are needed to deduce absolute numbers. A calibration between results from these two methods would facilitate the use of direct counts to estimate absolute numbers, an outcome that is relatively quick, cheap and minimises disturbance of animals. Mark‐recapture estimates for the numbers of New Zealand fur seal (Arctocephalus forsteri) pups in 2003 at 10 colonies at Otago, southeastern New Zealand, were compared with independent single counts at the same colonies. A single ratio to estimate absolute numbers (y) from direct counts x was not statistically significant. Instead, two ratios were deduced, based on differences in habitat among colonies: y = 1.51x for colonies with hiding places for pups and y = 0.96x for colonies without hiding places. Application of these calibrations and their 95% prediction intervals produce estimates and ranges for the absolute numbers of pups from single annual counts.     

Effects of the toxic dinoflagellate Alexandrium tamarense on the greenshell mussel Perna canaliculus

Abstract

Oxygen consumption, grazing rate, and byssus production of the greenshell mussel Perna canaliculus were measured following exposure to bloom concentrations (10⁶ cells l^?1 ) of a toxic clone of the dinoflagellate AIexandrium tamarense (GT429), using anon‐toxic clone of the same species (PLY173) as control. Following feeding for 1 h on GT429, mussels (dry weight 54–127 mg) showed significantly increased oxygen uptake at 15°C (0.08 μl O₂ (mg dry tissue weight)^?1 ) compared with control mussels. However, following 24 h recovery, oxygen uptake was similar to initial values in all experimental conditions. The grazing rate of P. canaliculus fed upon toxic clone GT429 was 4.58 ± 0.76 cells mg^?1 h^?1 compared with 1.99 ± 0.47 cells mg^?1 h^?1 for PLY173. On exposure to A. tamarense, mussels maintained normal opening behaviour and there was no change in the byssus production over 24 h. It was concluded that P. canaliculus showed no dramatic physiological effects following short‐term feeding on the toxic strain of A. tamarense. During 2 weeks’ exposure to twice daily bloom concentrations of GT429, there was no mussel mortality. Toxicity in the tissues was 1295 μg STX equivalent per 100 g tissue, levels at which these mussels would be unsuitable for human or animal consumption.     

Measurement of oxygen production and demand in lake waters

An analysis of the New Zealand whale stranding record by M. W. Bradyn. Science and Research Series 29. ISSN 0113–3713, ISBN 0–478–01278–6. Available from Department of Conservation, Wellington. Price: $15.00.

Fish quality control by computer vision, edited by L. F. Pau and R. Olafsson. Published by Marcel Dekker, Inc.