大连市区沿海底栖动物的种、量和对环境质量的评价

1997年10月－1998年7月对大连市区沿海10个站位（南部沿海4个站位，大连湾6个站位）进行了3次底栖动物调查，共获大底栖动物79种，其中多毛类42种，软体动物23种，节肢动物7种，棘皮动物2种，海鞘2种，其它3种，平均栖息密度为4663．3个／m^2，平均生物量为74．5g/m^2，同时测定了相关的水化指标，经分析表明该海区处于轻度和中度污染状态。     

中国北方盐碱水域中的底栖动物

1975～ 1 994年对山西省、河北省、内蒙古自治区和宁夏回族自治区的 2 6个盐碱水域 (盐度 0 5 8～ 1 6 3 0、pH 8 46～ 1 0 1 0 ) ,进行了 92个点的采集。共见到底栖动物 1 0 3种 ,分别隶属于环节动物、软体动物、昆虫类等 1 5个目。其中摇蚊科幼虫有 1 1个属、 48个种。其余为蠓蚊科幼虫、颤蚓科、锥实螺科、扁卷螺科、科、伪蜓科、划蝽科、牙虫科、叶科等种类。分析结果表明 ,所有水域的共同特点是以摇蚊幼虫为优势种群 ,其中花纹前突摇蚊幼虫和羽摇蚊幼虫出现率最高 ,均为 3 0 8%,其次为穴居摇蚊幼虫 ,出现率为 2 6 9%。其它底栖动物如鞘翅目牙虫科幼虫和寡毛纲颤蚓的出现率均为2 3 1 %。对水体主成分的水质分析结果表明 ,决定底栖动物分布和种数的主要因素是与总硬度、盐度和总碱度相关的水化学特征 ,其中底栖动物种数与总碱度呈显著的负相关关系 (R2 =- 0 3 4 2 ,n =2 6 ,P <0 0 5 )。     

三江平原井灌水稻生育期内水分供需平衡状况分析

对三江平原井灌水稻生育期内水分供需平衡状况进行了分析 ,找出在全生育期内亏水量最大的时期及多年平均数额。并采用经验频率曲线法建立了水稻净灌溉需水量 IN 与频率 P的函数关系 ,可供灌溉用水管理者参考     

Liberalization of Peru's formal seed sector

During the 1990s, the Government of Peru began to aggressivelyprivatize agriculture. The government stopped loaning money to farmers' cooperatives and closed the government rice-buying company. The government even rented out most of its researchstations and many senior scientists lost their jobs. As part of this trend, the government eliminated its seed certification agency. Instead, private seed certification committees were set up with USAID funding and technical advise from a US university. The committees were supposed to become self-financing (bycertifying seed grown by small seed producers) and each committee was supposed to encourage the development of a group of small seed-producing firms, clustered around the seedcertification agency. The amazing thing is that many of the seed committees actually accomplished these goals. The agronomists who staffed the committees stood by their jobs,even after US funding ended, even though the committees' income was (at best) modest, and occasionally under the threat of violence from the extreme left. Some seed certificationcommittees failed and others did not. Some of the problems with Peruvian agricultural liberalization can be seen in regard to the seed programs of maize, rice, potatoes, and beans. For example, the government abandoned most research, yet could not resist creating certain distortions in the seed market (e.g.,buying large amounts of seed and distributing them for political ends).     

植保无人飞机作业参数对田外除草靶标区内外雾滴沉积规律的影响

雾滴大小、气象条件和施药装备的作业参数对雾滴的覆盖范围、靶标的吸附性能有影响。无人飞机(UAV)是目前有助于高效喷雾的现代施药技术装备。然而作业参数对靶标区和脱靶区的影响依然尚待确定。开展了田间试验并运用沉积扫描软件测定了在田外除草中不同飞行高度(2 m和3 m)和飞行速度(2 m/s和3 m/s)下雾滴的沉积量、覆盖密度、覆盖率和雾滴直径。结果表明,当无人飞机在处理T_1中以2 m/s速度、2 m高度飞行时,靶标区域平均沉积量最高,为2.29μL/cm~2,飞行航线中央0点位置的覆盖率达到36.19%。处理T_1、T_2、T_3和T_4在飞行航线中央的雾滴谱相对宽度分别为0.70、1.01、1.03、1.05。处理T_1体积中值直径(VMD,也即D_(v0.5))最大,为448.75μm;而处理T_4的D_(v0.5)最小,为238.95μm。单旋翼无人飞机在脱靶区的沉积量几乎可以忽略不计。本研究为无人飞机运营商、农民和生产企业提供了参考,从而优化航空植保技术在除草上的应用。     

袋栽金针菇2潮后脱袋增产技术研究

为满足商品性要求,袋栽金针菇2潮后一般不再进行出菇管理。实际上,这时的菌棒仍有出菇趋势,由于塑料皮限制其生长,且阻碍补水补养,致使无法产生商品性好的菇,培养基中养分无法利用充分。试验中割破塑料皮,采用脱袋排场盖膜法和脱袋拱棚盖膜法进行继续出菇管理,并设置对照。结果表明,2种措施可分别再出菇3潮,生物学效率分别提高34％和28％,商品性满足三级以上标准,是可推广的金针菇增产措施。     

黄河口附近海域海洋生物体中石油烃总量变化的研究

在海洋污染中，石油污染是一个主要方面。近年来，随着沿海石油的勘探和开采，石油污染对海洋资源的危害日趋严重。本文就黄河口附近海域海洋生物体内石油烃含量及其相互关系进行了探讨。结果表明，各种海洋生物肌肉中石油烃含量依次为：双壳类＞头足类＞甲壳类＞鱼类，季节和个体大小及不同区域对石油烃含量也有一定的影响。     

磁珠富集法制备大口鲶的微卫星分子标记

2004年3月16日-6月8日，在广东广远渔业集团有限公司玻璃钢大滚筒冷海水金枪鱼延绳钓渔船“华远渔19”号，对印度洋马尔代夫海域进行金枪鱼渔业调查。所获数据资料包括：①CTD测定的温度、盐度和深度数据，TDR测定的实际钩深；②作业参数，包括每次作业的钩数、投绳位置、投绳时间、航向、航速、出绳速度、两浮子间的钩数、起绳位置、起绳时间等；③渔场环境数据，包括风速、风向、钓具对地漂移速度和方向；④渔获统计，包括大眼金枪鱼的渔获尾数以及部分大眼金枪鱼的钓获钩号；⑤生物学数据，包括起捕时已死的大眼金枪鱼的体温。分析计算的方法和步骤为：①由理论公式推算出每次作业时各钩号的理论深度；②应用逐步回归的方法，建立理论钩深与实测的平均钩深之间的数学关系模型；③根据实际平均钩深模型计算出每个钓钩的平均作业深度；④根据CTD测得的作业地点的温度、盐度的垂直分布（41次），获得分布曲线。由此，以计算的钩深，从曲线上查出该尾鱼捕获水深处的温、盐数据；⑤根据121尾大眼金枪鱼的取样数据，推算出各水层、水温段、盐度段的渔获率；⑥根据起捕时已死的34尾大眼金枪鱼（鱼体发硬）的体温、以死鱼体温为引数，在曲线上查出该尾鱼捕获水深和盐度；最后，对钓获的大眼金枪鱼的钓获水层、水温和盐度进行了总体分析。分析结果表明：在马尔代夫海域，捕获大眼金枪鱼的水层为50～210m、水温范围为13．0～29．9℃、盐度范围为35．00～35．79；渔获率最高的水层为70～90m、水温范围为27．0～27．9oC、盐度范围为35．70～35．79；捕获时已死鱼的捕获水层、水温和盐度推算数据为63～203m、14．0～27．0℃和34．94～35．42，主要集中在63～134m、16．0～27．0℃和35．30～35．42。     

南北湖渔业资源现状及开发途径的探讨

作者于１９９５年对位于杭州湾北岸海盐县境内的南北湖进行了周年浮生物种群组成调查及生物量季节变化的测定，由此估算出该湖食浮游生物及腐屑的鱼类增产潜力。鉴于南北湖是著名风景湖泊，在渔业上不宜采取投饵施肥方式增加鱼是疾病，但针对良料资源状况选择适宜品种，有节制地增殖放养某些经济鱼虾，不仅能     

Trends in carbon flux to seabirds in the Peruvian upwelling system: effects of wind and fisheries on population regulation

We hypothesized that change in the annual population size of guano‐producing seabirds (cormorant, Phalacrocorax bougainvillii; booby, Sula variegata; pelican, Pelecanus thagus) is a response to changes in primary and secondary production of the Peruvian upwelling system. We tested this hypothesis by modeling nitrate input through upwelling to the upper layers of the ocean off Peru between 6° and 14°S using data on wind stress and sea surface temperature. The model predicted the amount of carbon fixed by primary production each year from 1925 to 2000, which was then apportioned to the Peruvian anchovy (Engraulis ringens) biomass and ultimately to the seabird population and the anchovy fishery, the largest single‐species fishery on Earth. The model predicted a marked increase in primary production as a consequence of increasing wind stress. It overestimated the anchovy biomass after the collapse of the fishery in 1972, but closely predicted the growth of seabird populations from 1925 to the mid‐1960s, and their decline thereafter, explaining about 94% of the variation in seabird numbers from 1925 to 2000. The model indicates the seabirds consumed 14.4% of the available anchovies and, thus, that seabirds consumed 2.3% of the new production, before the development of the anchovy fishery, and only 2.2% of the available anchovies and 0.3% of the new production after the development of the fishery. The model results clarify the roles that environmental and anthropogenic factors may have had in regulating the guano‐producing seabird populations. It indicates that the growth of seabird populations from 1925 to 1955 was likely a response to increased productivity of the Peruvian upwelling system and that the subsequent drastic decline in seabird abundance was likely due to competition for food with the fishery, which caught ～85% of the anchovies, which otherwise would have been available for the seabirds. This model also shows that an increase in oceanic primary production promotes reproductive success and population growth in higher trophic level organisms.