Using fishers' anecdotes, naturalists' observations and grey literature to reassess marine species at risk: the case of the Gulf grouper in the Gulf of California, Mexico

Designing fishing policies without knowledge of past levels of target species abundance is a dangerous omission for fisheries management. However, as fisheries monitoring started long after exploitation of many species began, this is a difficult issue to address. Here we show how the ‘shifting baseline’ syndrome can affect the stock assessment of a vulnerable species by masking real population trends and thereby put marine animals at serious risk. Current fishery data suggest that landings of the large Gulf grouper (Mycteroperca jordani, Serranidae) are increasing in the Gulf of California. However, reviews of historical evidence, naturalists’ observations and a systematic documentation of fishers’ perceptions of trends in the abundance of this species indicate that it has dramatically declined. The heyday for the Gulf grouper fishery occurred prior to the 1970s, after which abundance dropped rapidly, probably falling to a few percent of former numbers. This decline happened long before fishery statistics were formally developed. We use the case of the Gulf grouper to illustrate how other vulnerable tropical and semi‐tropical fish and shellfish species around the world may be facing the same fate as the Gulf grouper. In accordance with other recent studies, we recommend using historical tools as part of a broad data‐gathering approach to assess the conservation status of marine species that are vulnerable to over‐exploitation.     

四环素类抗生素在土壤和堆肥中的吸附和降解

Two agricultural soils were collected from Dahu and Pinchen counties and swine manure compost (SMC) from Ping-tung County in Taiwan, China to investigate the sorption and dissipation of three tetracyclines (TCs), i.e., oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC), in compost, soils and soil/compost mixtures with different organic carbon (OC) contents. There were seven treatments in total. TCs were most strongly adsorbed to SMC in all treatments due to the high OC content. When SMC was present in the soils, the sorption of TCs was significantly enhanced, which might be attributed to the increased OC content and CEC. The adsorption of TCs showed non-linear adsorption isotherms and fitted well to the Freundlich model. After 49 d of incubation at 25 ℃ in soils and soil/compost mixtures in the dark, TCs elapsed in all substrates, with the time required for 50% degradation (DT₅₀) between 20 and 41 d, and the time for 90% degradation (DT₉₀) between 68 and 137 d. Soil amended with compost enhanced the stability of TCs and reduced their mobility. The dissipation of TCs in a soil environment was slow, indicating that these compounds might be persistent in soil.     

基于GIS的绿色农产品基地适宜性评价

建立和完善绿色农产品基地适宜性评价方法,提高评价结果的实用性和准确性,是实现农产品安全的根本保障。研究依据基地认证者、规划者、生产者3种评价主体实际需求,分别引入污染潜在风险指标和经济状况指标,建立面向不同评价主体需求的多种主导因子评价指标体系,并借助GIS的空间分析方法进行定量评价,最后以北京大兴区为例进行了案例分析研究。结果表明,基地与工矿企业距离、与居民地距离等潜在污染风险对基地适宜性限制大,且不同评价主体下建立不同指标体系使评价更具针对性,利用GIS功能可提高效率,评价结果可视化程度好,具有很强的     

草坪草信息微机管理系统的建立

收集整理了当前国内外可作为草坪草的 987个品种的资料 ,在微机上建立了较为完善的数据库 ,使用者可根据需要任意调用记录。在此基础上 ,设计了一个草坪草品种信息管理系统。通过本系统 ,使用者可对该数据库进行各种操作 ,实现微机贮存和快速查询、更正、添加记录的功能。     

通辽市速生树种良种繁育基地建设的探讨

文章在阐述速生树种良种繁育基地建设必要性的基础上,确定了建设目标和建设布局,区划良种培育工程区,规划了主要技术措施。     

不同早实核桃品种结果母枝结实能力的研究

为了改进栽培措施、使早实核桃连年丰产稳产,研究了不同早实核桃品种的不同类型结果母枝的结实能力以及1 a生枝的拉枝效果,结果表明,在所研究的早实核桃品种中,辽宁1号结果母枝连续结实能力最强,其4 a生枝段上连续3 a结果母枝比例及混合花芽比例分别为51.67%和55.83%;然后依次是辽宁3号、中林1号、绿岭和鲁果1号,分别为60.94%和36.30%、52.78%和36.99%、20.12%和42.83%、15.43%和15.30%。1 a生枝拉枝后的萌芽率平均为56%,未拉枝的仅36%,拉枝后平均新梢结果数提高了10%。     

节水农业文献数据库专题期刊研究

采用文献计量学方法，对节水农业文献数据库涉及的388种专题期刊进行统计、分析。结果表明：本库收录的专题期刊既保证了收文质量，又保证了查金率、查准率；且节水农业文献学科归属具有高度的集中性与广泛的离散性，这对节水农业科教人员和文献信息工作者充分、有效地使用该数据库，具有一定的导示作用。     

提高板坯预压效果的研究

为提高板坯预压效果，对ＵＦ树脂的制法和调胶进行了改进，试验结果表明，在ＵＦ树脂制造时加入氨基磺酸，调胶时加入保水剂，可使树脂水溶性增加，贮存期延长，胶液活性期长，并可防止干燥胶合现象。胶粘剂的预压效果好，所压制的胶合板质量符合ＧＢ９８４６．１－９８４６．１２－８８Ⅱ类胶合板标准，ＵＦ树脂成本不增加。     

论革命老区农业高质量发展——以江西赣州为例

高质量发展是全面建设社会主义现代化国家的首要任务。支持革命老区加快发展，是党中央的重大战略部署和战略决策。本文以江西赣州革命老区为对象，分析其农业高质量发展的优势和存在的问题，探讨推动赣州革命老区农业高质量发展的实现路径。研究表明，推动赣州革命老区农业高质量发展具有重要的政治意义、经济意义、生态意义和社会意义。党的十八大以来，赣州革命老区农业高质量发展取得巨大成就，不仅实现了脱贫摘帽、促进了经济发展，还改善了生态环境、提升了农产品品质、打响了赣州农业品牌。新时代，进一步推动赣州革命老区农业高质量发展具有诸多有利条件和优势，如气候优越、资源丰富、生态良好和政策支持等。但同时必须看到，当前赣州革命老区农业高质量发展也存在不少问题和短板，主要有粮食生产下滑、耕地资源闲置、农田污染较重、农业效益下降、农村劳力缺乏和农业基础脆弱等。因此，为推动新时代赣州革命老区农业高质量发展，提出充分利用耕地资源，大力发展粮食生产；夯实农业发展基础，改善农业生态环境；扩大农业生产规模，提高农业经济效益；强化农业科技支撑，培养新型职业农民等对策建议。     

新形势下热科院科研基地土地管理的对策研究

2006年初,中国热带农业科学院科研基地的院试验场下属的原宝岛公社5个单位的生产队(村)以多种方式要求退出试验场编制,严重影响了中国热带农业科学院科研事业的发展。院国有资产管理处经过一年多的详细调查,认真分析了中国热带农业科学院试验场土地管理中存在的问题,提出一些解决对策,以期探讨新形势下切实可行的科研基地管理模式。