Direct impacts of commercial and recreational fishing on spiny lobster,Panulirus interruptus,populations at Santa Catalina Island,California, United States

The California spiny or red rock lobster, Panulirus interruptus, is an ecologically and economically important species that has been exploited since the 1800s. No previous study in California has assessed the impacts of the recreational or commercial lobster harvest. Before the 2003–04 commercial and recreational lobster seasons, we conducted a fishery‐independent trap survey at Santa Catalina Island to document the impact of the lobster fisheries on the size structure, abundance, and sex ratios of mature P. interruptus (>65 mm carapace length (CL)). We concurrently sampled a predominantly commercially fished area, a recreationally fished area, and a 23‐year‐old invertebrate no‐take (INT) reserve. Relative to the INT reserve, legal‐size lobsters in the recreational area were similar in CL, but 31% less abundant. Legal‐size lobsters in the commercial area were 8% smaller and 70% less abundant than those in the INT reserve. The sex ratio of legal‐size lobsters, although near 50:50 in the recreational and INT reserve areas, was male‐dominated (67:33) in the commercial area. Differences in CPUE and mean CL of sub‐legal lobsters in the recreational and commercial areas suggest that factors in addition to harvesting pressure may affect these populations. Total biomass of mature lobsters in the recreational and commercial areas was 92% and 45%, respectively, of biomass in the INT reserve. Fecundity in the recreational and commercial areas was 83% and 42%, respectively, of fecundity in the INT reserve. This study provides preliminary data for future ecological studies and fisheries management evaluations.     

The Beaufort Gyre variation and its impacts on the Canada Basin in 2003–2012

The Beaufort Gyre (BG) was spun up in the last decade which is an important factor in regulating the variation of the upper ocean. The heat content and freshwater content of the upper ocean increased g...     

Using compliance data to improve marine protected area management

Measuring the ‘level of compliance’ has emerged as a key performance indicator for MPA success internationally. Accurate interpretation of quantitative and qualitative compliance data is critical for determining which compliance activities contribute to specific management outcomes. To demonstrate the value of enforcement data in effective MPA management, more than 5000 enforcement actions from 2007 to 2013 from five New South Wales (NSW) Marine Parks were analysed. Specifically, it was tested whether through time: (i) the number of enforcement actions standardised by surveillance effort declined-indicating that ‘general deterrence’ was being achieved; (ii) the number of repeat offenders decreased-indicating that ‘specific deterrence’ was being achieved; (iii) the number of ‘local community’ enforcement actions standardised by surveillance effort declined-indicating growing support for marine parks was being achieved at the community level; and (iv) the percentage of young offenders (<25 yr) had declined-indicating that education programs targeting young adults were successful. Results indicated that general deterrence was not being achieved, with offence rates being relatively stable between years. In contrast, compliance measures were achieving individual deterrence, with the percentage of repeat offenders being very low (0.13–0.83%). Although compliance strategies may be making some progress in improving local compliance in some marine parks, the overall offence rate of local communities was concerning. The data suggested that there were major differences in compliance rates among age groups of offenders over time, although the percentage of young offenders declined over time in three marine parks. Over the six-year data collection period, there was no discernable improvement in compliance rates in most NSW Marine Parks. Overall, the significant value of collecting and analysing information on enforcement activities for MPAs was demonstrated, an often neglected aspect of their management world-wide.     

黄河、长江、钱塘江水样中胶体对铅吸附络合容量的影响

用过滤和切向超滤将黄河、长江和钱塘江的水样分成＜ １ ．０μｍ 、＜ ０ ．４μｍ 和＜ ５０００Ｄａｌｔｏｎ （ 相当于１ ．５ｎｍ 孔径） 三种级分,对铅在不同级分上的吸附络合容量进行了初步探讨。铅在不同级分上的吸附络合容量差别很大,滤膜孔径越小,吸附络合容量越小。的黄河水样真溶液中的配体对铅的键合能力相对较强,而粒级较大的络合能力相对较弱;长江水样较大粒级的配体对铅的键合能力相对较强;钱塘江水样的各粒级配体的键合能力相似。胶体对三种江河水体的吸附络合容量具有很大贡献,黄河水样＜ １ ．０μｍ 的吸附络合容量中,１ ．５ｎｍ ～１ ．０μｍ 的胶体部分的吸附络合容量占总量的８２ ．５ ％ ,其中以０ ．４ ～１ ．０μｍ 大粒径胶体为主;长江和钱塘江水样中１ ．５ｎｍ ～１ ．０μｍ 的胶体部分的吸附络合容量分别达到了总量的５７ ．７ ％ 和５６ ．８ ％ 。     

黄河、长江和钱塘江水样不同级分滤液与铅吸附络合反应动力学的初步研究

采用过滤和切向超滤将黄河、长江和钱塘江水样分成＜ １ ．０μｍ ,＜ ０ ．４μｍ ,＜ ５０００Ｄａｌｔｏｎ （ 相当于１ ．５ｍｍ 孔径） 三个级分,分别对三个级分滤液与铅进行吸附络合反应的动力学进行了初步研究。黄河水样＜ １．５ｎｍ 超滤液与铅吸附络合反应呈快反应,＜ ０．４μｍ 和＜ １ ．０μｍ 的各级过滤液呈慢反应;长江和钱塘江水样各级滤液均呈慢反应。长江和钱塘江水样与铅反应存在络合竞争,反应速率取决于竞争离子络合物的解离速率;黄河水样则没有络合竞争。黄河水样＜ ０ ．４μｍ 和＜ １ ．０μｍ 的滤液与铅的络合反应速率由铅与胶体之间的反应决定,反应速率由液膜扩散控制。     

理想化南极融冰方案的海洋边界条件初探

基于气候态的SODA(simple Ocean Data Assimilation)数据,比较了气候态意义下南极附近和南极绕极流区域的海洋层结,对南极融冰问题的合理海洋边界条件进行了初步探讨.结果表明:南极融冰所注入的淡水通量在大西洋东部和印度洋海区将沿着表层路径到达南极绕极流区,在大西洋西部和太平洋的经向运动路径视淡...     

海河流域平原区土壤碳密度分布特征和碳储量估算

基于2003年以来多目标区域地球化学调查积累的大量表、深层土壤有机碳、全碳分析数据,以土壤类型和土地利用类型为基本计算单元,本文重点对海河流域平原区土壤碳密度与碳储量分布规律进行了研究.结果表明:海河流域表、深层土壤全碳和有机碳密度空间分布规律基本一致,总体均表现为"北东呈带、区域连片","南部高于北部,山前高于平原,城市高于农田"的特征.从土壤类型上看,湿潮土的有机碳密度最高,为17.92 kg/m2,其次为石灰性褐土,达到15.49 kg/m2,草甸风沙土的有机碳密度最低,为7.9 kg/m2;有机碳密度最大者与最小者相差将近2倍.从土地利用类型来看,耕地的有机碳密度最高,这与近年来推广的秸秆还田和人工施肥有关.     

Characterisation of sea-water intrusion in the Pioneer Valley, Australia using hydrochemistry and three-dimensional numerical modelling

Sea-water intrusion is actively contaminating fresh groundwater reserves in the coastal aquifers of the Pioneer Valley, north-eastern Australia. A three-dimensional sea-water intrusion model has been developed using the MODHMS code to explore regional-scale processes and to aid assessment of management strategies for the system. A sea-water intrusion potential map, produced through analyses of the hydrochemistry, hydrology and hydrogeology, offsets model limitations by providing an alternative appraisal of susceptibility. Sea-water intrusion in the Pioneer Valley is not in equilibrium, and a potential exists for further landward shifts in the extent of saline groundwater. The model required consideration of tidal over-height (the additional hydraulic head at the coast produced by the action of tides), with over-height values in the range 0.5–0.9 m giving improved water-table predictions. The effect of the initial water-table condition dominated the sensitivity of the model to changes in the coastal hydraulic boundary condition. Several salination processes are probably occurring in the Pioneer Valley, rather than just simple landward sea-water advancement from “modern” sources of marine salts. The method of vertical discretisation (i.e. model-layer subdivision) was shown to introduce some errors in the prediction of water-table behaviour.     

矿床模型综合地质信息预测资源量的估算方法

未发现矿产资源潜力的资源定量估算一直是资源评价的重要工作,关于资源量估算的方法也在不断的探索中。从新一轮全国重要矿产资源潜力评价的技术体系所倡导的成矿分析方法入手,探索了资源量估算的成矿地质体体积法,介绍了该方法的原理、步骤和可能实现的途径。     

淡水水体沉积物磷的环境生态效应研究进展及建议

对淡水水体沉积物磷的环境生态效应的国内外研究热点和领域进行了综述、评价;提出了尽快开展真正内源磷——地质成因磷自然释放的水环境生态效应研究,特别是天然条件下（如人为干扰少的源头河流）,富磷河流水体主要初级生产者——藻类生态响应研究的建议。