国外封闭循环水养殖系统工艺流程设计现状与展望

以发达国家成功运行的养殖系统为出发点,按照不同养殖鱼类的生活习性、水体流态以及水处理工艺特性的不同,将其归类为4种典型鱼类的循环水养殖系统工艺(常规游泳性鱼类、鲆鲽类、鲑鳟类、鳗鲡等),分析探讨每种工艺的设计理念、设计思路等,总结工艺流程设计技术特征,展望未来发展趋势,提出循环水养殖工艺流程设计较为特殊的3种模式,从而为封闭循环水养殖系统设计提供技术参考。     

巴图湾水库风沙入库量的估算

风沙入库给干旱、半干旱地区的水库带来了严重的填淤危害。本文通过对内蒙古乌审旗南部巴图湾水库岸边流动沙丘不同部位风速与风沙流的同步观测,计算出库岸流动沙丘表面的平均输沙率。利用巴图湾水库1986~2005年9月份的5期TM遥感影像统计出水库两岸受不同风向影响的流动沙丘断面的平均长度,结合巴图湾水库附近乌审旗河南乡气象站1985~2004年的气象资料,统计出不同风向大于起沙风的风速年均持续时间,初步计算出巴图湾水库的年均入库风沙量。结果表明:(1)巴图湾水库的年均入库风沙量为3.65万t,其中西岸风沙入库量为3.55万t,东岸为0.10万t。西岸风沙危害最为严重,是治沙工作的重点。(2)巴图湾水库的风沙入库具有明显的时间性和方向性。受季风气候的影响,风沙入库的方向会随着风向的变化而改变。东南风与西北风是造成东西两岸风沙入库的主要风向。西北风对风沙入库量的贡献最大。(3)在大于起沙风的风速中,5~12 m/s风速段是风沙入库的主要风速。当风速中7 m/s以上的风速持续时间有一个较小的增加时,入库风沙量将会有一个巨大的增加。(4)库岸半固定沙丘的风沙入库,降尘和风水复合侵蚀引起的库岸坍塌也是入库风沙量的重要组成部分。因此,巴图湾水库的实际年入库风沙量应该大于3.65万t。     

The role of river flow in the migration of adult Atlantic salmon,Salmo salar,through estuaries and rivers

An assumption of Atlantic salmon, Salmo salar L., management is that river flow influences their upstream migration; but the quantitative relationships between flow and movements are variable and inconsistent. A consensus has emerged that standard rules on salmon flow needs for water management across all rivers are unattainable. However, this does not preclude an underlying conceptual framework that should guide a consistent scientific basis to flow management for protecting salmon. This article examines the potential for a conceptual framework from a British Isles perspective, assuming that upstream migration is an emergent property from selection to optimise lifetime fitness. The template for this adaptation is the diversity of river types and hydro‐morphology in British rivers coupled with life‐history and migration adaptations that may be influenced by flow‐related factors. Models of adult salmon migration through estuaries and rivers are outlined that may provide a basis for developing generic guidance.     

The role of the UK conservation agencies in protecting river flows

Abstract An outline is given of the scale and nature of special wildlife designations in the UK river network, the general approach of the UK conservation agencies to their evaluation and management, and the specific way in which impacts of river flows are handled. The need for a holistic ecological and biodiversity view of water resource impacts on river systems is stressed, within which the specific needs of individual species, such as Atlantic salmon, Salmo salar L., can be framed. An approach founded on the provision of a natural flow regime within a natural physical channel not only provides the most suitable conditions for characteristic riverine wildlife to flourish but also provides the best local defence against global climate change. Arguments are made for a future focus on the generic evidence base for flow targets and its strengthening through strategic and demonstrably fit‐for‐purpose research. The practical constraints to an approach based on protection of the natural flow regime are discussed. Ultimately, transparent separation and consideration of what river ecosystems really need, and what can realistically be provided, is the key to shared ownership of the water resource dilemma.     

Performance of hybrids between transgenic oilseed rape (Brassica napus) and wild Brassica juncea: An evaluation of potential for transgene escape

Understanding the potential for the evolution of herbicide tolerance in weeds following gene flow from transgenic crops is important for their management. The inter-specific hybrids formed between four Brassica juncea populations with different glyphosate-susceptibility and transgenic oilseed rape was studied, emphasizing on the possible population difference. Compared with both parents, the fitness-related components and photosynthetic capacity of hybrids decreased dramatically, but significant differences were observed among different hybrids. All F₁ hybrids exhibited highly enhanced but similar herbicide tolerance level regardless of the wild B. juncea parent, indicating that genetically engineered herbicide tolerance may over-dominate phenotype ones by wild-crop hybridization. The analysis of parental loci transmission revealed a higher transfer ratio of male-specific loci detected in F₁ hybrids, suggesting that oilseed rape genetic markers can be transferred at relatively high frequencies to the next generation. Therefore, higher transfer ratio of oilseed rape-specific loci, coupled with variation of populations in fitness-related parameters in F₁ hybrids, could complicate environmental risk assessment of transgenic oilseed rape, especially in current agroecosystems with increasing application of glyphosate.     

不同杀青工艺对松阳香茶品质的影响

本文针对松阳香茶存在的色泽不绿,香气不高等品质问题,采用不同杀青温度和不同的投叶量处理,研究其对松阳香茶品质的影响。结果表明：其他工艺相同的基础上,采用80型滚筒杀青机杀青,下锅温度以250℃,投叶量在100kg／h时,炒制的香茶品质最佳。     

一种利用流式细胞术鉴定梨倍性的方法

流式细胞术鉴定植物染色体倍性的方法广泛应用于果树多倍体育种中,然而相关流式细胞术鉴定梨染色体倍性的方法还没有系统的研究。以梨树叶片为试材系统优化了各个流式细胞术关键实验节点,结果表明：实验材料选取当年春季新梢第3~5 片梨树嫩叶,尤其是大棚新梢嫩叶最好;叶片前处理时用蒸馏水、去离子水依次洗净叶片表面后,再用去离子水浸泡10 min;使用WPB解离液对梨叶片细胞核进行提取后,用500 目滤膜过滤2 次,离心1 次后用流式细胞仪进行检测可得到理想的实验结果。该方法步骤简单、结果可靠,是一种快速、高效的梨染色体倍性鉴定的方法,可广泛用于梨树多倍体鉴定。     

纵轴流玉米脱粒分离装置喂入量与滚筒转速试验

在玉米籽粒直收过程中,脱粒滚筒转速与联合收获机的额定喂入量相匹配才能发挥出最佳的作业效果。为了获得不同喂入量时玉米联合收获机最优的滚筒转速范围,设计了一种零部件可更换、结构参数和工作参数均可调的纵轴流玉米脱粒分离装置,并在自主研制的试验台上以脱粒滚筒转速、喂入量为影响因素,以籽粒破碎率、未脱净率为性能指标进行玉米脱粒试验。通过台架试验、回归分析和单变量求解,最终确定了不同喂入量的最优滚筒转速范围:喂入量为8 kg/s时,最优的滚筒转速为254~486 r/min;喂入量为10 kg/s时,最优的滚筒转速为278~466 r/min;喂入量为12 kg/s时,最优的滚筒转速为313~445 r/min。在以上条件下籽粒破碎率均小于5%,未脱净率小于2%,达到了国家和相关标准的要求。     

适合草莓倍性鉴定的流式细胞术方法的建立

比较了3种提取液制备红颊、川九1号、吉林草莓细胞核悬液流式细胞术检测效果,结果显示,提取液Ⅲ主峰粒子团清晰而集中,背景碎片少,试剂配方简单配制容易,且3种草莓材料倍性差异区分明显,优于其他2种提取液。对红颊草莓不同部位或不同来源的材料进行流式细胞术检测效果比较,结果表明,组培苗的检测效果明显优于大田试材,组培苗叶片因取材容易、主峰清晰、杂峰少、细胞碎片少而成为最佳试材。