热带,亚热带玉米种质的研究与利用

探讨了热带,亚热带玉米种质利用的意义,国内外的研究进展和发展趋势,提出了研究利用的方法及利用的前景。Ｓｕｗａｎ－１、墨白１号,ＥＴＯ复合种是广泛利用的热带种质,Ｙｕｃａｔａｎ是有待开发利用的热带种质,已育成了Ｎｃ２９６、ＮＺ１Ａ辐苏１,等１１３等优良自交系和７８５９９、９９６１,等优良杂交种。     

玉米热带,亚热带种质资源利用的现状及展望

针对玉米育种遗传基础狭窄的突出问题,分析了热带、亚热带种质研究和在育种中利用的现状,存在问题,指出要加强我国引进,研究和利用热带,亚热带种质的工作,讨论了温热杂优模式,光敏感等问题研究了一些思路。     

Epilithic biofilm as a key factor for small‐scale river fisheries on Caribbean islands

Abstract Numerous freshwater species are consumed or exploited through artisanal fisheries in the rivers of the islands of Guadeloupe, French West Indies. Autochthonous production of organic matter is limited in these flowing rivers and is mainly represented by scarce filamentous green algae and an abundant epilithic biofilm growing on wet stones in the river bed. Stable isotope analysis was used to quantify the relative importance of biofilm and other riverine allochthonous and autochthonous food sources in the diet of tropical shrimps (Palaemonidae, Atyidae and Xiphocarididae) and fishes (Gobiidae and Eleotridae) consumed by the local people. The epilithic biofilm was exploited by most species, constituted an important source of autochthonous carbon and was an important source of organic matter production at the base of freshwater food webs in Caribbean rivers. Biofilm percentages in the diet reached 32% for molluscs, 85% for atyid shrimps, 29% for xiphocaridid shrimps, 14% for palaemonid shrimps and 13% for fish. Assessment of biofilm in nine rivers showed that blue and red cyanobacteria were quantitatively dominant with a moderately rich diatom flora. These results address the interactions between river biofilm and Caribbean freshwater fauna where trophic links between consumers and their potential resources have poorly been documented.     

避风型渔港避风因素浅析

我国的东南沿海是最容易遭受热带气旋影响的脆弱地带,每年的5-11月,都会遭受热带气旋的影响,对渔港、渔船和渔民构成严重威胁.而渔港的避风能力是渔民最为关心的问题,通过近几年登陆我国的强台风等级以上的热带气旋对渔港、渔船及渔民造成损失的实例分析,从防波堤设计标准、避风锚地的底质、锚泊方式等3个方面对避风型渔港的避风因素展开讨论,得到了有价值的结论,为渔港、渔船和渔民减少灾害,为政府建设避风型渔港决策提供科学依据.     

海口人民公园的发展探讨

分析海口人民公园的发展现状及存在的问题,探讨热带地区城市公园发展过程中所面临的困境,提出城市老公园的发展思路。     

Availability and plant uptake of nutrients following the application of paper pulp and lime to tropical acid soils

Availability and plant uptake of nutrients were evaluated in three tropical acid soils (Kandiudult) amended with paper pulp and lime under greenhouse conditions. Amendments were applied to attain target pH values of 5.5, 6.0, and 6.5. A control treatment (no paper pulp or lime added) was also included. Rye grass (Lolium perenne L.) as a test plant was grown for three successive cycles of 40 days each. Extractable nutrients and cumulative nutrient uptake were determined. The application of paper pulp or lime resulted in a significant increase in exchangeable Ca and K and a decrease in exchangeable Mg and extractable Fe, Mn, and Zn. Amendment of soils with paper pulp or lime increased plant uptake of Ca and Mg and decreased that of K, Mn, and Zn. Both amendments behaved similarly, but the effect of lime seemed generally greater than that of paper pulp. Paper pulp in tropical acid soils behaved as a liming agent rather than an organic amendment. Similar to lime, amendment of soils with paper pulp resulted in an increase in availability of Ca and Mg and in a decrease in availability of K, Mn, and Zn for plants. Soil extractions appeared to be appropriate for assessing the availability of Ca, Mn, and Zn. Soil pH and effective cation exchange capacity positively influenced the availability of Ca and negatively the availability of Mn and Zn. Thus, the precision of predicting nutrient availability in paper pulp amended tropical acid soils could be improved by including soil pH or effective cation exchange capacity in relevant regression equations.     

Migratory history of the giant mottled eel (Anguilla marmorata) in the Bonin Islands of Japan

Chino N, Arai T. Migratory history of the giant mottled eel ( Anguilla marmorata ) in the Bonin Islands of Japan.
Ecology of Freshwater Fish 2010: 19: 19–25. © 2009 John Wiley & Sons A/S
Abstract –  In order to elucidate the migratory history and habitat use of the giant mottled eel Anguilla marmorata, in the Bonin Islands of Japan, strontium (Sr) and calcium (Ca) concentrations in otoliths were examined by X-ray electron microprobe analysis. The X-ray intensity map and line analyses showed three fluctuation patterns: (i) freshwater residence, (ii) continuous residence in brackish water, and (iii) residence in freshwater after recruitment, while returning to brackish water. Based on these results and previous studies, the migratory behaviours of A. marmorata appear to differ in each habitat in response to inter- and intra-specific competition. The results suggest that A. marmorata has a flexible pattern of migration, with an ability to adapt to various habitats and salinities.     

Assessment of induction and recovery times of anaesthesia in Astyanax bimaculatus using 2‐phenoxyethanol and the essential oils of Melaleuca alternifolia and Ocimum gratissimum

This study aimed to determine the lowest effective concentration (LEC) of 2‐phenoxyethanol (2‐Phe) and essential oils (EOs) of Melaleuca alternifolia and Ocimum gratissimum able to induce anaesthesia in Astyanax bimaculatus. LEC was assumed to be the required concentration to carry out anaesthesia in less than 3 min with recovery in <5 min and sufficient to carry out routine aquaculture procedures. The following concentrations were tested: 2‐Phe (100, 200, 300, 400, 500 and 600 µl/L); M. alternifolia (200, 300, 400, 500 and 600 µl/L); and O. gratissimum (10, 20, 30, 40, 50, 60, 70, 100, 150, 250 and 300 µl/L). Results show that all three agents evaluated have effective anaesthetic properties for use in Astyanax bimaculatus with LEC for 2‐Phe, M. alternifolia and O. gratissimum of 200, 300 and 60 µl/L respectively.     

海南省兰花优势区域发展布局

根据海南各地的气候、环境条件和产业基础等,将全省兰花种植区划分为琼北部-东北部兰花优势区、琼南部-西南部兰花优势区和琼中部山地兰花优势区;针对海南兰花产业存在的问题,提出海南兰花发展的对策与建议。     

迎接生物经济浪潮与热带农业科技创新

21世纪上半叶,一场由生物技术推动的科技革命和产业革命,将在全球爆发,其影响将是人类历史上任何一次产业革命都不可比拟的。各国都开始纷纷抢占这一战略高地。生物经济时代距离我们已不再遥远。生物技术产业具有资源、技术依赖性强、市场垄断性差等特点,为发展中国家特别是资源丰富、技术基础相对落后的国家．带来跨越式发展的历史性机遇。热带农业发展与生物技术进步密切相关,应用现代生物技术提升热带农业是迎接生物经济浪潮的必然要求。