在希望的海洋牧场上——记长海县现代海洋牧场建设

长海县陆域面积只有119平方千米,海域面积却有7720平方千米,可以说是"小"县"大海".人们傍水而居,必然要缘水而兴,渔业便很自然地成了海岛人安身立命的本钱.随着海洋生物资源的衰减,渔业的内涵产生了质的变化,由起初的"打鱼摸虾"演变为"耕海牧鱼";由"猎捕型"转变为"栽培型".而作为"栽培型"产业的海水养殖,虽然是长...     

Shrubs proliferated within a six-year exclosure in a temperate grassland—Spatiotemporal relationships between vegetation and soil variables

Overgrazing has been considered one of the maj or causes that trigger shrub encroachment of grassland. Proliferation of shrubs in grassland is recognized as an important indicator of grassland degradation and desertification. In China, various conservation measures, including enclosures to reduce livestock grazing, have been taken to reverse the trend of grassland desertification, yet shrubs have been reported to increase in the grasslands over the past decades. In late 2007, we set up a 400-m-by-50-m exclosure in a long-term overgrazed temperate grassland in Inner Mongolia, with the ob- jective to quantify the spatiotemporal relationship between vegetation dynamics, soil variables, and grazing exclusion. Soil moisture was continuously monitored within the exclosure, and cover and aboveground biomass of the shrubs were measured inside the exclosure in 2007, 2009, 2010, 2012, and 2013, and outside the exclosure in 2012 and 2013. We found the average shrub cover and biomass significantly increased in the six years by 103 % and 120%, respectively. The result supported the hypothesis that releasing grazing pressure following long-term overgrazing tends to trigger shrub invasion into grassland. Our results, limited to a single gradient, suggest that any conservation measures with quick release of overgrazing pressure by enclosure or other similar means might do just the opposite to accelerate shrub en- croachment in grassland. The changes in vegetation cover and biomass were regressed on the temporal average of the soil moisture content by means of the generalized least square technique to quantify the effect of the spatial autocor- relation. The result indicates that the grass cover and biomass significantly increased with the top, but decreased with the bottom layer soil moisture. The shrub cover and biomass, on the other hand, decreased with the top, but increased with bottom soil moisture, although the regression coefficients for the shrubs were not statistically significant. Hence this study supports the two-layered soil model which assumes grasses and shrubs use belowground resources in dif- ferent depths.     

中国近海大黄鱼和日本带鱼群体数量变动及其资源保护措施探讨

作者根据长期调查研究,分析了大黄鱼(Larimichthys crocea)和日本带鱼(Trichiurus japonicus)群体数量变动的因果关系,并提出了加强我国海洋渔业资源科学监管的建议:(1)正确划分大黄鱼和带鱼地理种群及其产卵群体,为资源繁殖保护提供参考依据;(2)修订若干《渔业法》条款,重新审定《官井洋大黄鱼繁殖保护区管理规定》;(3)充分合理开发利用闽东渔场近海岛屿周边海域,并且采用抗风浪升降式圆柱形深水养殖网箱养殖大黄鱼;建立内湾性官井洋大黄鱼海洋牧场渔业基地,并新建中国著名舟山渔场大黄鱼繁殖保护区;(4)继续加强大黄鱼原种场建设,大力开展大黄鱼良种选育研究,每年提供大批量野生大黄鱼人工培育的原种子一代幼鱼进行增殖放流;(5)巩固和扩大伏季休渔效果,全年禁止违法而严重损害带鱼幼鱼资源的各种张网作业;(6)以法治渔,加快制定符合于我国实情的海洋渔业科学监管的有效措施.     

对矿物中位错和位错增殖的几点认识

本文主要以前人的实验结果为依据，从理论角度分析和讨论了有关位错的几个问题。指出通过测量矿物的位错密度值计算得到的外应力只能是矿物变形过程中所受峰值应力的下限，位错的运动速度随着外施应力和温度的增高而加快，从奥洛旺方程的位错速度与应力的关系出发，提出了矿物晶体中位错随外应力增加而非线性增殖的一个原因。     

围隔生态系中可溶性锰对两种形成赤潮藻类增殖的影响

1991年春秋两季,在厦门的临海陆基水池中进行了两次海洋生态系围隔实验,对海水中可溶性锰与赤潮发生规律大小的关系作探索性的研究。实验时人为地引发了中肋骨条藻(Skeletonema costatum,春)和颤藻(Oscillatoria,秋)的赤潮。实验用的厦门西海域海水,其可溶性锰含量在3～4μg/dm3的水平时,就足够藻类形成赤潮的增殖需求。若含量升高,在低于80μg/dm3情况下,过量的可溶性锰不影响浮游植物的数量和群落结构。但处于mg/dm3含量水平的可溶性锰,会影响浮游植物群落结构,浮游植物的数量也受到一定程度的抑制。     

中国对虾(Penaeus chinensis)肝胰腺上皮细胞质中杆状病毒增殖的电镜观察

对中国对虾肝胰腺上皮细胞进行透射电镜观察。指出：对虾杆状病毒可在肝胰腺上皮细胞的胞质内增殖，与以细胞核内形成包涵体为特征的增殖方式明显不同。溶酶体在增殖过程中内吞濒临解体的线粒体和病原体，利用线粒体内嵴提供的能量，有规律地组装成杆状病毒的包涵体。这一结果为探讨对虾暴发大面积死亡的病因分析提供了新的途径。     

增殖渔业应成为21世纪渔业经济的支柱产业

改革开放以来,我国海洋水产业有了飞速发展,据有关资料,从1978年～1998年的20年间,我国水产品产量增长了6倍多,其总量已连续10余年保持在世界首位。但应该承认的是,伴随着渔业经济的迅猛发展,我们同时也付出了巨大的资源与环境代价。尽管海洋捕捞我们已从近海走向了远洋,并且实行了休渔制度和渔船控制等措     

官井洋大黄鱼标志放流技术与放流标志鱼早期生态习性性的初步研究

用人工培育的大黄鱼幼鱼，经丁香酚溶液浸溶麻醉、体背系挂塑料牌，经网箱暂养后于１９８７年１月２０日在官井洋中放流６２１６尾。２个月内回捕４８３尾。通过对回捕鱼及其捕捞实况调查，并结合定置网渔获物中天然大黄鱼及海区温盐断面调查，对放流标志鱼早期的生态习性进行了初步研究。     

人工渔礁工程中几个技术问题探讨

论述了人工渔礁工程在增殖渔业资源和改善海洋生态环境方面的作用;阐述人工渔礁工程增殖渔业资源和改善海洋生态环境的机理;总结、归纳目前人工渔礁工程上的一些较成熟的技术和作法;展望未来人工渔礁工程的发展前景。