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1.
根据漠斑牙鲆(Paralichthys lethostigma)适广温、广盐和较强的抗逆性等优良生态习性,采用地下卤水、盐碱地渗水,通过合理淡水配兑使其适合漠斑牙鲆生理生长需求,在我国中纬度地区利用盐碱地低盐水养殖过洋、暖温性漠斑牙鲆。2004-2005年,利用盐碱地低盐水池塘虾池设置网箱套养漠斑牙鲆349.5m2,产鱼3.749t,产虾55.065t,其中2005年虾池设置网箱套养漠斑牙鲆306m2,产鱼3.245t,平均10.6kg/m2,平均全长34.0cm,体重527.4g,养殖成活率为90.5%,产虾49.003t,平均408.4kg/亩,平均规格11.9cm,养殖成活率为71.23%。虾池设置网箱套养漠斑牙鲆,可充分利用水体空间,促使池塘高产高效,提高养殖经济效益。  相似文献   
2.
在未治理塌陷地水域,设置生态养鳙网箱52箱。使用生态养殖技术(不投饵),利用微生物制剂及人工诱导饵料生物技术,在25m~2网箱内放养鱼种300尾,其中鳙规格为165g/尾。经过137天的养殖,网箱平均单产19.72kg/m~2,其中鳙单产14.97kg/m~2,折合每667m~2产鳙9985kg。网箱平均产值达138.06元/m~2,净收入为99.66元/m~2,投入产出比为 1∶3.59。  相似文献   
3.
通过对漠斑牙鲆淡水池塘网箱养殖试验,掌握了该品种的生活习性,探索出漠斑牙鲆内陆地区淡水养殖模式,总结出养殖过程中应采取的技术措施。25m~2网箱总产漠斑牙鲆102.9 kg,平均单产4.12 kg/m~2,平均规格为306.25 g/尾,成活率达84%。  相似文献   
4.
  1. Population structure of highly mobile marine organisms can be complex and difficult to study, but it is important to understand how populations partition themselves within their environment for accurate assessment of both natural and anthropogenic impacts and successful management. The 2010 Deepwater Horizon oil spill negatively impacted common bottlenose dolphins (Tursiops truncatus) within Mississippi Sound and the surrounding north central Gulf of Mexico (GOMx); however, little was known about their underlying population structure in these waters. Thus, it was unclear how many demographically independent populations were affected by the spill.
  2. Common bottlenose dolphin samples were collected throughout inshore waters of Mississippi Sound and coastal waters of the north-central GOMx. Mitochondrial DNA control region sequence data and 19 nuclear microsatellite loci were analysed to determine how many populations are present and characterize their range throughout these waters.
  3. Bayesian clustering and migration analyses identified two genetically distinct and demographically independent populations: one predominantly inhabiting Mississippi Sound and adjacent coastal waters, and a second population extending generally from offshore of Mobile Bay, Alabama, east along the Florida Panhandle. Neither of these populations align with the currently delineated management stocks previously used to estimate impacts from the oil spill on common bottlenose dolphins in this portion of the GOMx.
  4. These results suggest that revisions may be necessary so that management stocks accurately represent the demographically independent populations present in these waters. Furthermore, better comprehension of underlying population structure will enhance impact assessments on common bottlenose dolphins and provide more appropriate baseline data to support future restoration and conservation objectives.
  相似文献   
5.
唐岛湾网箱养殖对水环境的影响   总被引:1,自引:1,他引:1  
2004-08~2005-05分4个航次对唐岛湾网箱养殖区的水环境进行了现场调查,分析讨论了网箱养殖对水环境的影响。结果表明,唐岛湾网箱养殖对海水的水温、盐度、透明度、DO、pH的影响不显著,对叶绿素a浓度的影响显著(t-test,P〈0.05)。养殖区CODMn虽然也显著高于对照点,但主要受陆源污染的影响,与网箱养殖关系不大。养殖区和对照点海水中无机氮的主要形态均以NO^3--N为主,其次是NH^4+-N,NO2^--N最少,DIN、3种形态无机氮、无机磷的季节变化趋势也比较一致。除了NH^4+-N外,唐岛湾网箱养殖对溶解态无机氮磷营养盐(NO3^--N、NO2^--N、DIN、PO4^3--P)的影响并不显著(t-test,P〉0.05),但养殖区内的含量比对照点有了一定程度的升高。以DIN和PO4^3--P作为N、P阈值来分析,目前唐岛湾网箱养殖区的水质未超出二类水质标准。唐岛湾网箱养殖区海水各季节的营养指数E值均小于1,表明养殖区的水质状况尚未达到富营养化水平。  相似文献   
6.
从养殖区选择及网箱设置、放苗、饲料选择、日常管理、病害防治等方面介绍了褐篮子鱼网箱养殖技术,以供养殖户参考。  相似文献   
7.
《Plant Production Science》2013,16(4):441-446
Abstract

Submergence induces rapid elongation of internodes in floating rice (Oryza sativa L.). We examined the distributions of p-coumaric, ferulic and 5-5-coupled diferulic acids ester-linked to cell walls along the axis of highest internodes of submerged and air-grown floating rice stem segments. The amounts of ferulic and 5-5-diferulic acids per cell wall weight were lowest around the intercalary meristem, and increased as the distance from the meristematic zone increased toward the upper part of the internode in both air-grown and submerged stem segments. The ratio of 5-5-diferulic acid to ferulic acid also increased toward the upper, old parts of internodes in both air-grown and submerged stem segments. These observations suggest that the feruloylation of cell wall polysaccharides and the formation of diferulic acids contribute to the cessation of internodal cell elongation and that the formation of diferulic acids in cell walls is controlled by the coupling reaction in addition to the feruloylation. The amounts of p-coumaric acid per unit length and per cell-wall weight were markedly low in the newly elongated region of submerged internodes, and closely correlated with cell-wall dry mass in both air-grown and submerged internodes, suggesting that the deposition of p-coumaric acid in cell walls is related to the formation of secondary cell walls in floating rice internodes.  相似文献   
8.
介绍了眼斑拟石首鱼的形态特点,对生态环境的要求,以及苗种的选择、运输、网箱暂养、池塘养殖等技术。  相似文献   
9.
革胡子鲶成鱼网箱养殖技术   总被引:1,自引:0,他引:1  
在小浪底水库进行的革胡子鲶成鱼网箱养殖试验获得成功.由于大水面的理化特点,培养出来的革胡子鲶肉质鲜美,食用价值高,而且推迟了销售时间,提高了销售价格,取得了显著的经济效益.  相似文献   
10.
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