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151.
绥芬河滩头雅罗鱼孵化放流的初步试验   总被引:1,自引:0,他引:1  
本文首次报道绥芬河滩头雅罗鱼大批量人工孵化放流。1989年5~6月,在绥芬河东宁河段采捕、利用(?)河亲鱼3037尾,采卵1867万粒,利用自然产卵场生态条件孵化放流的雅鱼1323万尾(全长6.5mm)。  相似文献   
152.
A standing surgical technique for splitting the medial patellar ligament is described, and the long-term (average 4.5-years) efficacy of the procedure in horses exhibiting delayed patellar release is reported. Medical records of 64 horses that underwent a standing medial patellar ligament splitting surgery performed to treat delayed patellar release were analyzed retrospectively. Horses were sedated in standing stocks. A number 15 scalpel blade was used to percutaneously split the medial patellar ligament from just proximal to its insertion on the tibial tuberosity to its attachment on the parapatellar fibrocartilage, with the goal of inducing a localized desmitis and subsequent thickening of the ligament. Aftercare consisted of oral antibiotics, 14 days stall rest with hand walking, light exercise for 14 days, and full work at 4 weeks. Follow-up information was obtained through telephone calls to owners and/or clinical evaluation by a veterinarian. Results showed that 89% of horses benefitted from the procedure, with complete resolution in 58% of horses and improvement in 31% of horses. A total of 73% of horses were able to perform at the desired level following the procedure; 63% of horses showed signs of improvement or resolution within 30 to 60 days. Two horses had complications following the procedure: 1 horse had an incisional infection, and 1 had a medial patellar ligament rupture. This study shows that standing medial patellar ligament splitting is a successful, long-term surgical option for treatment of delayed patellar release. The procedure has few complications and allows rapid return to desired performance.  相似文献   
153.
浙北沿岸大黄鱼放流增殖的初步研究   总被引:9,自引:2,他引:9  
为了恢复浙江渔场大黄鱼资源,1998—2002年,浙江省在浙江北部沿岸海域进行了大黄鱼增殖放流可行性研究。通过5年来的放流试验表明,在浙北沿岸进行大黄鱼放流是完全可行的,放流鱼能够在放流区域附近海域存活、生长,并进行索饵、产卵洄游,同时形成了一定数量的捕捞群体,放流鱼回捕率较高,放流效果较好。文章对试验放流过程中出现的问题进行了探讨和分析,为今后进一步大规模放流提出了建议。  相似文献   
154.
ABSTRACT:   The effects of 80% methanol extracts from frozen samples of 41 macroalgae and one sea grass collected in the Ise-Shima region of Japan were investigated on histamine release from rat basophile leukemia cells (RBL-2H3) sensitized with antidinitrophenyl (DNP) IgE and stimulated with DNP-BSA. Of the 21 brown algae, five green and 15 red algae, and one sea grass tested, only extracts from seven brown algae suppressed histamine release from RBL cells, as determined by high-performance liquid chromatography (HPLC) analysis. When the cytotoxic effects of the seven brown algal extracts were investigated by Trypan blue staining, only Eisenia arborea and Sargassum thunbergii did not show cytotoxic effects. Therefore, we conclude that E. arborea and S. thunbergii may contain compounds that have antiallergic effects without inducing cell death.  相似文献   
155.
Fishery collapses cause substantial economic and ecological harm, but common management actions often fail to prevent overfishing. Minimum length limits are perhaps the most common fishing regulation used in both commercial and recreational fisheries, but their conservation benefits can be influenced by discard mortality of fish caught and released below the legal length. We constructed a computer model to evaluate how discard mortality could influence the conservation utility of minimum length regulations. We evaluated policy performance across two disparate fish life‐history types: short‐lived high‐productivity (SLHP) and long‐lived low‐productivity (LLLP) species. For the life‐history types, fishing mortality rates and minimum length limits that we examined, length limits alone generally failed to achieve sustainability when discard mortality rate exceeded about 0.2 for SLHP species and 0.05 for LLLP species. At these levels of discard mortality, reductions in overall fishing mortality (e.g. lower fishing effort) were required to prevent recruitment overfishing if fishing mortality was high. Similarly, relatively low discard mortality rates (>0.05) rendered maximum yield unobtainable and caused a substantial shift in the shape of the yield response surfaces. An analysis of fishery efficiency showed that length limits caused the simulated fisheries to be much less efficient, potentially exposing the target species and ecosystem to increased negative effects of the fishing process. Our findings suggest that for overexploited fisheries with moderate‐to‐high discard mortality rates, reductions in fishing mortality will be required to meet management goals. Resource managers should carefully consider impacts of cryptic mortality sources (e.g. discard mortality) on fishery sustainability, especially in recreational fisheries where release rates are high and effort is increasing in many areas of the world.  相似文献   
156.
磷形态和pH对剩余污泥磷释放的影响   总被引:2,自引:2,他引:0  
为了探讨pH对污泥中磷的释放行为的影响,采用SMT(欧洲标准测试组织)法对上海三处污水处理厂的剩余污泥中磷的形态进行了分析,并通过室内模拟实验研究了不同pH条件下3种污泥中的磷在海水中的释放行为。结果表明:3种污泥样品的总磷含量各不相同,污泥有机磷含量低,无机磷是主要赋存形态,占TP(总磷)含量的64.42%~83.01%。各形态磷的相关性分析发现,污泥总磷含量主要受NAIP(非磷灰石无机磷)和AP(磷灰石无机磷)影响。室内试验表明,污泥中的磷在酸性、中性和碱性海水环境下均有释放,相比中性条件,酸性和碱性水质更有利于磷的释放;污泥中磷的释放与磷的形态分布有关,但磷释放量大小并不简单取决于总磷和无机磷的含量。  相似文献   
157.
砂壤质潮土夏玉米适宜的化肥种类研究   总被引:3,自引:1,他引:2  
采用田间试验研究Agro Services International Inc(ASI)推荐施肥、缓/控释肥、保水型复混肥和普通复混肥对夏玉米产量、SPAD值及养分吸收积累的影响。结果表明,夏玉米施用缓/控释肥和ASI推荐施肥增产效果较好,分别比农户习惯施肥处理增产11.0%和9.8%,保水型复混肥没有显著增产效果。夏玉米专用缓/控释肥养分缓慢释放可弥补砂壤质潮土保肥性差的缺点,能维持夏玉米各生育时期较高的叶片叶绿素含量,促进夏玉米对氮、磷、钾养分的吸收利用,提高干物质积累量,具有显著增产效果,是砂壤质潮土区夏玉米适宜的化肥品种。  相似文献   
158.
施用缓释肥料对夏玉米产量的影响试验   总被引:2,自引:0,他引:2  
采用田间试验,研究了施用缓释肥料对夏玉米产量及经济效益影响。结果表明:施用缓释肥料能显著提高夏玉米的产量和经济效益。与常规施肥相比,施用缓释肥料可使夏玉米每667m2增产45kg,经济效益提高89元。进一步研究表明,缓释肥料促进玉米增产的主要原因是增加了玉米的穗长,从而提高了穗粒数。  相似文献   
159.
采用盆栽试验和室内分析化验相结合的方法,研究了多酶金缓释尿素对油菜田土壤氮素及油菜植株全氮含量、氮肥利用率和土壤氮素依存率的影响。结果表明,多酶金缓释尿素在石灰性褐土中抑制尿素水解显著有效作用时间在油菜移栽后20 d以内,20 d以后多酶金缓释尿素处理的土壤铵态氮、硝态氮和无机氮分别为5.26,9.08,14.34 mg/kg,显著高于多酶金尿素和普尿;多酶金缓释尿素处理的土壤有机氮、全氮和植株全氮比多酶金尿素和普尿分别提高了13.55%,13.67%,9.85%和21.75%,21.82%,19.60%,且差异显著;多酶金缓释尿素处理的氮肥利用率最高,为45.19%,土壤氮素依存率和氮素损失最低,分别为40.13%和1.21 g/盆,而多酶金尿素处理的油菜产量比多酶金缓释尿素和普尿分别提高了5.38%,8.11%,这可能与肥料释放养分特点和油菜生长特性有关。  相似文献   
160.
干扰树间伐对马尾松人工林目标树生长的初期效应   总被引:9,自引:0,他引:9  
2007年10月在相同林分条件的14年生马尾松人工纯林中进行干扰树间伐,在间伐和对照地块各建立固定样地20块,并于2010年11月进行复测。基于间伐试验后的3年数据,研究干扰树间伐对目标树胸径、树高、枝下高、冠幅直径和材积生长的影响。结果表明:干扰树间伐前后,目标树生长均明显快于非目标树;干扰树间伐后3年,目标树的胸径生长量和材积生长量分别高于未间伐林分目标树的80%和55%,树高生长则差异较小,枝下高生长明显减慢,冠幅直径生长年均提高0.44 m,同时林分内较大径级的林木数量增加;随着目标树自由生长方向数的增加,目标树的胸径和材积生长增加,树高和枝下高生长没有明显的规律性;影响目标树生长的决定因素是目标树自由生长方向数。因此,间伐不应该仅仅注重间伐强度,而且要注重哪些林木(即干扰树)应当被间伐,以便目标树生长得更好。  相似文献   
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