972 resultados para 11,12-methylene-Hexadecanoic acid, d13C


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Larval development of the sidestriped shrimp (Pandalopsis dispar) is described from larvae reared in the laboratory. The species has five zoeal stages and one postlarval stage. Complete larval morphological characteristics of the species are described and compared with those of related species of the genus. The number of setae on the margin of the telson in the first and second stages is variable: 11+12, 12+12, or 11+11. Of these, 11+12 pairs are most common. The present study confirms that what was termed the fifth stage in the original study done by Berkeley in 1930 was the sixth stage and that the fifth stage in the Berkeley’s study is comparable to the sixth stage that is described in the present study. The sixth stage has a segmented inner flagellum of the antennule and fully developed pleopods with setae. The ability to distinguish larval stages of P. dispar from larval stages of other plankton can be important for studies of the effect of climate change on marine communities in the Northeast Pacific and for marine resource management strategies.

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本文主要通过大量的植物群落学调查和植被、环境状况的数量分析,分别从植物区系、森林群落及其主要木本物种、干扰和物种多样性五个方面分析了三峡大老岭地区山地植被景观的空间格局及其与环境因子的关系,结果表明: 1) 植物区系:科的分布区类型以热带性质为主;属一级温带性质明显,北温带、东亚和泛热带诸分布类型突出;区系上属于华中植物区系地区的东部。 2) 在垂直梯度上:种子植物属热带分布诸类的比例自海拔400至800米(~1100米)之间呈上升趋势,然后下降;温带分布的第8、9、10、11类随海拔而上升;地中海-中亚中心分布的第12、13类只见于比较干热的河谷地带;东亚分布和中国特有属在海拔900~1100m和1600~1800m段取得小的峰值;世界分布属的比例随海拔而上升,蕨类植物属则相反。 分别用种子植物属的分布型比列构成,和全部521个属的种类数量,对15个海拔段作聚类分析:前者首先反应了海拔1100~1200m处的划分,与植被干扰状况的垂直分布差异一致;后者强调了海拔900/1000m和1800/1900m 处的分异,可能反映了地带性常绿阔叶林基带/常绿落叶阔叶混交林带,和常绿落叶阔叶林带/落叶阔叶林带的分异。 3) 对本地区森林植被的数量分类结果表明:基本上可以分为中低海拔次生落叶 针阔混交林和中高海拔山地常绿落叶阔混交林两大群。第一群主要包括栓皮栎林-杉木林-马尾松林组(低海拔段)和短柄抱栎林-锥栗林组(中低海拔段)。第二群包括中低海拔沟谷常绿阔叶林组、中海拔段常绿落叶阔叶混交林组和高海拔段米心水青冈林-茅栗林组。 DCCA排序区分了11个群落类型或群落组。采用的7个地貌因子变量中效果显著的可归纳为三组:①海拔,主要反映热量和降水梯度;②坡度和坡位,可能主要反映土壤厚度及其水分和养分状况;③坡向及坡位,反映光照条件。其中植被格局的海拔梯度效应最显著。沿海拔梯度分段分析上述诸因子对植被格局差异影响的垂直分布,表明海拔因子的局部效应在海拔600-800m和1500-1700m段最显著;坡向的效应在海拔1600m以上最突出;坡面、坡位、坡形、坡度等因子的作用在海拔中部最大。对植被格局影响因子的贡献进行定量分离,表明地形对对大老岭森林格局具有强烈的控制作用。 4) 对大老岭森林植被275个主要的木本种类进行TWINSPAN分类,得到16个种组;DCCA排序结果将上述16组合并为8群,两方面都主要反映了沿海拔和坡位+坡向的分化;海拔中部的局部地形差异导致物种组的分化比两端更细致和强烈。 根据物种生活型及其在植物群落中的地位,分6个种组进行排序和环境解释,表明:①尽管低海拔地段受到强烈人为干扰,常绿种类仍显示了数量和性质沿海拔梯度的变化;②珍稀物种在海拔梯度上形成两个相对集中的区段,大致对应于山地常绿落叶阔叶混交林带的上下边缘;③先锋树种在中低海拔的中上坡位富集;④在中、高海拔的中低坡位,落叶的乔木伴生种显示了极大的多样性;⑤为数不多的针叶树种在海拔和局部地形梯度上也有明确分异;⑥它们和落叶的栎(Quercus)、栗(Castanea)、水青冈(Fagus)、鹅耳枥(Carpinus)属物种在大老岭地区不同地形部位的植被中起着主要的建群作用。 具体统计海拔梯度上,常绿和落叶的乔、灌木4类物种分布的种数变化表明:海拔1100m以下人为活动干扰与木本物种多样性呈一致的负相关;海拔1100m以上常绿种减少与与落叶种的增加形成对照;1100~1700m之间是落叶乔木种最丰富的地段,海拔1700m以上四类物种数量急剧下降,与山顶脊附近生境多样性降低、植物群落类型趋同有关。另外,典型亚热带的棕榈和蕉只见于海拔1000m以下;针叶树种以海拔1150m左右为界分成两组。前述4类物种的分布边界在海拔850~1050m和海拔1650~1750m之间形成比较明显的峰值,基本对应着山地常绿落叶阔叶混交林带的上下边缘。 根据海拔分布范围,将样方中出现的558种木本植物按常绿乔/灌种和落叶乔/灌种分别分成5个热量生态类群。统计各自的面分比表明:a. 落叶灌木种的多样性分布重心在海拔梯度上的位置比落叶乔木种高,常绿种则相反,因此灌木和类的分布特征能更好的反映次生环境中的植被-气候关系;b. 在海拔850~1850m的木本物种形成巨大的多样性,仅出现于这一段的物种也很可观;亲缘物种的分化和替代突出,反映其对生物多样性发生和维持的意义重大;c. 亚热带中山地带对落叶种生物多样性的意义远大于常绿种。 5)统计全部群落样方内枯立木、倒伏木、断头木和伐桩四类受干扰木的大小、数量、物种以反映地形对干扰的影响:①枯立木以2~15cm径级个体为主,小径级的树种选择性不强,主要分布在山南坡口上坡位,海拔1800m以上尤多,在陡峭的坡地中部减少;其大径级个体的物种构成和分布格局反映了与生境干旱有关干扰的存在。②倒伏木主要分布在海拔1200~1800m之间坡面中部和顶脊两侧,发生频率与坡度成正比;坡地中部以中、小径级阳性树种为主,山坡顶脊两侧的倒伏木则多为大径级的群落优势种。③断头木主要分布在海拔1200~1700m,和海拔1900m以上。小径级的断头木分布格局接近于枯立木,较大径级的断头木则多与倒伏木的分布相关,断头木中少有典型的阳性树种,主要由林下荫耐种构成。④人为砍伐的伐桩主要为中大径级的植被建群种或优势种个体,在海拔1000m以下,1100-1200m和1600-1800m形成三个峰值,其分布主要与人口密度、生产方式、林木种类以及交通运输便捷程度有关,通常沟谷和山脊线上的伐桩密度较大。大老岭地区人为干扰主要反映在海拔1100m以下,自然干扰的格局在海拔1100m以上才得到反映。 6)在不同取样尺度上,对大老岭地区森林群落各层次α多样性和β多样性的空间格局分析表明:i. 乔木层α多样性在海拔1200-1800m之间取值较高,灌木、草本层α多样性的垂直梯度不显著,但在海拔1200-1800m之间的波动变化较为剧烈,南坡面有最丰富的灌木层多样性而西坡乔木层的物种最丰;从植被整体上,海拔1000m以下物种丰富度较低,1000-1700m之间变化剧烈,1700m以上丰富度水平较高。ii. 海拔1000-2000m之间94个样方中,乔、灌、草三层多种生物多样性指数变化影响因子的大小顺序是:坡位>海拔>坡向>坡面>坡度>坡形。乔、灌、草各层几种多样性指数在多维的地形因子梯度上形成各异的分布格局,反映了山地物种多样性格局控制因子的多样性和多尺度,及局部地形因子对景观尺度上生物多样性空间格局的强烈影响。iii.对海拔1050m和1670m处植被α多样性的变尺度分析表明:随取样尺度增大,低海拔乔木、灌木层α多样性增长速率比高海拔大;后者草本层的多样性增长比较快。海拔1050m处群落各层的α多样性在800m~2尺度上渐近稳定;海拔1670m处,400m~2尺度上各层α多样性指数已基本稳定。 南、北、西坡面β多样性沿海拔梯度大致减少,在海拔1600m以上更明显,在海拔梯度中部变化剧烈。反映不同坡面上群落间异质性水平是:西坡>北坡>南坡。 在对植被、环境上述各个方面的格局特征分析基础上,对三峡地区侵入岩山地类型建立了一个综合的植被景观格局模式。 文章最后就两个景观尺度植被-环境的综合性问题进行了讨论:1)气候、植物区系、植被和物种分布等对老岭以至于三峡地区和亚热带山地常绿落叶阔叶混交林带的位置、宽度的反映;和气候、地形、干扰等因子对这一生态过渡带格局和动态的影响;2)三峡地区生物多样性垂直分布的特征、维持和变化的现代机制,以及保护的重点和策略

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毛乌素沙地是我国十二大沙漠之一,地处北方干旱半干旱区向亚湿润区过渡地带,长期以来,不合理的人类土地利用,结合当地脆弱的环境生态特征,引起了严重的现代荒漠化过程,是我国北方荒漠化研究的重点地区。本文着重从自然和人文学科密切合作的角度,对毛乌素沙地土地利用/土地覆被变化的内在作用机制进行了研究,得到以下主要结论: 1. 利用多年实地观测数据资料,考察了毛乌素沙地四种主要草地类型代表性植物群落地上生物量响应气候因子波动的变化规律,建立了植物地上生物量对气候因子的逐月回归模型,揭示出如下规律:①各种气候因子对不同类型草地以及同一类型不同生长阶段草地都产生不同的影响作用;②同一气候因子在植物不同生长阶段上,对生物量形成的重要性程度存在差异:③在植物生长期内,每个生长阶段的生物量都对后一时期的生物量产生显著影响,说明植物生长的连续性对于生物量的形成和积累是重要的;④在植物的凋枯期,各种气候因子基本上都不对生物量产生显著影响;⑤水分因子对毛乌素沙地几乎各种类型草地的生物量,都是重要的影响因子,毛乌素沙地降水状况在不同年份的显著波动对草地植物地上生物量的影响,不仅直接构成了土地覆被变化的重要组成部分,而且还影响到土地利用的方式、方法和后果。 2. 在考察毛乌素沙地草地地上生物量对气候因子变化的响应规律中,利用逐月动态回归建模方法改进了传统的累积气候因子回归建模方法。逐月回归模型与累积回归模型的比较显示,逐月动态回归模型的优势表现在三个方面:①可以提供累积回归模型无法揭示的作用规律;②模拟更加精确;③可以预测不同气候条件下群落地上生物量的变化范围。 3. 利用风速、降水和潜在蒸发等气象记录资料,建立了毛乌素沙地气候因子影响沙尘暴频率的作用模型,定量地考察了沙地各处气候因子对沙尘暴频率的影响作用。研究表明,气候因素是导致毛乌素沙地沙尘暴发生的主导原因,在沙地各处,气候因子可以解释沙尘暴频率分布格局总信息的比率分别为:乌审召83.6%,乌审旗77.5%,河南82.4%,鄂托克旗79.8%,新街73.1%,伊金霍洛旗82%。 4. 在定量考察气候因素对沙尘暴频率影响作用的基础上,对影响沙尘暴频率格局的自然和人为因素进行了定量分离,研究表明:人为影响因素对对沙尘暴发生起次要作用,解释沙尘暴频率分布格局信息的比率分别为:乌审召16.4%,乌审旗22.5%,河南17.6%,鄂托克旗20.2%,新街26.9%,伊金霍洛旗18%。 自然和人为因素影响作用的定量分离研究表明,毛乌素沙地人为因素的影响作用表现出空间上的差异性:①从方位上说,呈现自东向中、西部递减的梯度:②从地点上说,城镇附近人为影响作用远高于农村地区;③从土地利用方式上说,农垦种植业区域高于畜牧业区域。 5. 在实地观测基础上,建立了裸露沙面和植被覆盖沙面风蚀输沙率模型,定量考察了植被覆盖率与风蚀输沙率之间的关系。研究表明:当植被覆盖率达到60%以上,可以保护地表土壤使风蚀在大多数条件下不致发生;当覆盖率达到40%,可以使风蚀输沙大为减少;而当植被覆盖率低于10%,植被覆盖基本不能对地表土壤起到有效的防护作用。 6. 应用植被覆盖地表风蚀输沙率模型,考察了沙地不同风速条件下植被有效覆盖率。根据当地气象台站的多年气象记录,沙地最大风速在20m/s左右,这样的风速条件下,保证风蚀不致发生的植被有效覆盖率为65%左右;在沙地常见的大风风速14-16m/s下,植被有效覆盖率大致为50-55%;对于沙地一般的中等风速l0-12m/s.植被有效覆盖率为40%。植被覆盖对风蚀的影响作用也可以理解为,植被覆盖使沙粒起动风速发生了增大效应,研究表明:与裸露沙面沙粒起动风速4.5m/s对照,70%植被覆盖率使起动风速改变为15.4m/s;60%植被覆盖率使起动风速改变为12.1m/s;40%植被覆盖率使起动风速改变为8.Om/s;而在10%植被覆盖条件下,起动风速为5.Om/s,改变量很小,说明植被覆盖的保护作用极其有限。 7. 基于野外实地观测,比较了沙地五种常见植物种和二种人工防护材料防风效应上的差异。研究表明,防风效应由高到低的次序是,沙蒿>芨芨草>杨柴和牛心朴子>沙障>栅栏>旱柳;就乔、灌、草和人工材料而言,防风效应的次序是,灌木植被>草本植被>人工材料>乔木植被。植物和人工防护材料降低风速的比率与风速呈现二次函数关系,不同植物种或人工材料,降低风速比率都表现出不同的规律,在一般情况下,降低风速效应随着风速的增大而降低。 8. 通过不同植物种防风效应的比较研究,对毛乌素沙地植被生态建设的实践有一定的指导意义。毛乌素沙地的植被建设中对植被类型和植物种类的选择,应该遵循如下原则:①选取防风固沙效应好的植物种类;②应该考虑植物水分供给与需求的平衡状况,实行适地适树;③植物防护效应应该与当地风蚀气候在时间上较好地匹配,在春季等风蚀严重季节,植被覆盖应该具有较好的防风效应。 9. 在现实中,各种影响风蚀的因素是同时发挥作用的。将风蚀影响因素分解为风速、湿润度和植被覆盖率(以及植被类型)三个方面,在此基础上,建立了风蚀影响因素的综合作用的概念模型和沙丘活动性指数定量模型。湿润程度低、风速高、植被覆盖率低的地区,是风蚀最为严重的地区;在湿润程度高、风速低、植被覆盖率高的地区,是风蚀最弱的地区;在其他地区,风蚀状况根据三个方面因素的综合状况来决定。 10. 利用风蚀影响因子综合作用的沙丘活动性指数模型,从空间、时间、植被类型变化角度,考察了毛乌素沙地的风蚀变化状况。得到如下结论:①随着空间变化,风速、降水等气候因素也随之存在差异,导致沙丘活动性指数的变化规律是,西北部鄂托克旗沙丘活动性最高,乌审旗次之,其他几个站差别不太显著,这是由各地降水、气温、沙粒粒径等因素共同决定;②随着时间的变化,气候、植被生长等方面的状况随之发生改变,导致沙丘活动性发生变化,春季最高,冬季次之,夏秋季最低:③随着沙丘植被覆盖类型的变化,沙丘活动性也发生显著变化,在一般情况下,乔木覆盖沙丘活动性>草本植物覆盖沙丘>灌木覆盖沙丘。 11. 在实地调查土地利用现实状况及其社会、经济和政策影响因素的基础上,建立了我国北方干旱半干旱区土地利用决策机制的概念模型,分析了与土地利用密切相关的农牧民一政府一环境科学家这三个社会群体对土地利用的立场和影响作用力上的差异,分析了毛乌素沙地土地利用的现状及其影响因素,探讨了现实中不可持续土地利用行为发生的社会、经济和政策原因。 12. 在实地调查基础上,分别利用产出一费用分析法和过程影响因素分析法,建立了毛乌素沙地土地利用经济收益的定量模型。产出一分析研究表明,无论是农垦种植业,还是草地畜牧业,农牧民从这两种土地利用方式都只能获得较低下的经济收益。造成这种状况的原因,主要在于两个方面:一是低下且不断处于波动之中的农牧业产品物价,二是沉重的农牧业税收。 13. 将影响农牧业产出的因素,划分为四个方面:土地面积(牲畜头数)、环境状况、管理水平和利用强度,在此基础上建立了定量的影响作用模型。研究表明:环境状况指数每增加0.1,农牧业经济收益增加26%;管理水平因子每提高0.1,农牧业经济收益增加12.7%;农牧业经济收益最优的土地利用强度在0.4左右,在此之前,随着利用强度的增加,经济收益随之增大,而在此之后,随着利用强度的增大,经济收益逐渐降低,当土地利用强度达到0.9左右时,呈现负的经济收益。 14. 毛乌素沙地实施土地资源可持续利用,必须从技术的革新和社会经济政策等因素的调整两条途径同时入手,二者缺一不可。通过改进和应用节水灌溉、风能光能利用、生物增产技术,尽可能地提高各种资源的利用效率;通过应用免耕或浅耕技术,尽量减轻土地利用对资源和环境的破坏;通过栽培、速生技术,提高植被建设的成效和速度。而通过税收、物价政策的调整,尽可能地提高农牧民经济收益增长的速度,减轻土地利用压力;通过政府与人民之间对话和合作机制的建立,让广大农牧民参与到土地利用的决策和管理的过程中去;通过土地利用管理政策、措施的调整和完善,调动农牧民保护资源的积极性和自觉性;通过激励机制的建立,引导农牧民土地利用向着可持续的方向发展。 15. 实现毛乌素沙地土地资源可持续利用的有效途径,在于这样几个方面:①建立和完善政府及其管理部门与人民之间有效的对话和合作机制,让广大农牧民参与到土地利用决策和管理的过程中去:②实行产业结构调整,转变片面追求经济增长的做法,制订适应当地自然条件和生态特征的发展模式;③降低农牧业税收、稳定并提高农牧业产品的物价,增加农牧民经济收入,减轻土地利用压力;④进一步改进和完善土地利用管理政策和法规;⑤建立有效激励机制,引导农牧民土地利用向着可持续的方向发展:⑥努力改进节水灌溉技术、生物增产技术,提高土地利用的科技水平:⑦改进环境保护和植被建设决策的科学性,提高植被建设的成效。

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Heteropneustes fossilis was induced bred for the first time in the agro-climatic conditions of Maharashtra, India. The embryonic development was completed within 16-18h after fertilisation. Head and tail ends were distinguishable after 3h and 11-12 somites were visible after 6-7h. The eggs started hatching after 14h of incubation. Average hatching time was 16-18h at 26 degrees C. In first day old pro-larva, notochord was deflected upwards, eyes were darkly pigmented and alimentary canal appeared. In fourth day old post-larva intestinal coiling could be seen and yolk was absorbed. Aerial respiration started by 8th day. The 10 day old post-larva was free swimming and fed voraciously attaining a length of 20 mm in 30 days.

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Minced fish prepared from the fillets of the sciaenid fish (Lutjanus sp.) was washed with cold water (<10 °C) three times. The washed muscle was pressed through a piece of fine cloth to a moisture content around 80%. The pressed cake (Surimi) was ground with 2.5% sodium chloride and 3% tapioca starch. The mixed material was shaped in the form of a cake and left for one hour for the gel to set. The cakes were then steamed. The cooled cakes were cut into pieces of 1 cm length x 1 cm width x 0.5 cm thick. The pieces were either dried in an electrical oven at 50°C or dried in sun to a moisture content of 11-12%. Biochemical, bacteriological and organoleptic evaluation revealed that the cakes were in very good acceptable form for 8 months. The cakes could be rehydrated by soaking in water at ambient temperature for half an hour and boiling in water for 10 minutes.

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Sperata aor and S. seenghala are the two important native catfishes of Bangladesh but commercial farming of these species is not possible due to lack of naturally collected or artificially produced seeds for stocking. Attempts were made to develop techniques for seed production by artificial breeding and nursery-rearing of fries of these catfishes. A total of 60 S. seenghala (750-1,500 g) and 10 S. aor (600-1,000 g) broods were collected from the Brahmaputra river-basin and floodplains in Mymensingh region four months prior to their breeding season. The collected brood fishes were reared in separate earthen ponds with supplementary feeds comprising of rice bran (40%), mustard oil cake (29%), fish meal (30%) and vitamin-premix (1 %). Three experiments were conducted to optimize the hormone dose. A total of nine S. seenghala females weighing from 750 to 1,500 g were given an initial and resolving dose of 12-20 and 16-24 mg PG/kg body weight, respectively. The males weighing from 650-950 g were administered a single dose of 18-26 mg PG/kg body weight at the time of the time of administering the resolving dose to the females. The females ovulated partially and the eggs were examined under a compound microscope, but most of them were found to be less ripe or damaged. Collection of milt by stripping the males was not successful. The testes were taken out and sperm were observed to be non-motile and less developed. In view of stimulating natural propagation of S. seenghala, artificial holes (nests) were constructed in the pond bottom. Each hole was 0.7 m in diameter and 0.3 m in depth. A total of 10 holes were made and then 10 pairs of S. seenghala breeders (800-1,200 g) were stocked in the pond. In mid February, 3,000 fry of S. seenghala with a mean length of 4.60 cm and weight of 0.36 g were collected by repeated netting followed by drying of the pond. The fry were then stocked in a nursery pond and fed with commercial feed (SABINCO starter-1). The average length and weight of the fingerlings were 9.01 cm and 3.95 g, respectively and the estimated survival was 60% after two months of rearing. S. aor did not respond to natural spawning. Further study is essential to develop techniques for their successful artificial and natural breeding.

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一种抗艾滋病的药物,其中含有抗艾滋病有效量的式(Ⅰ)化合物反-1硝基2-苯硫基-乙烯用及可药用载体和/或赋形剂。$同时提供一种逆转录酶抑制剂,其中含有式(Ⅰ)化合物反-1硝基2-苯硫基-乙烯及可药用载体和/或赋形剂;式(Ⅰ)化合物反-1硝基2-苯硫基-乙烯在制备抗艾滋病药物中的应用;式(Ⅰ)化合物反-1硝基2-苯硫基-乙烯在制备逆转录酶抑制剂药物中的应用。

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The article presents environment friendly aquaculture practices such as semi-intensive aquaculture, the culture of native species, the selection of proper sites for aquaculture facilities, the conduct of thorough, honest socioeconomic and ecological impact assessment before proceeding with the implementation, and the practice and promotion of proper pond/cage/tank preparation and management among others.

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Schizothorax zarudnvi, is an endemic fish of east country waters. (Triple lagoons of Hamoon and relevant water resources) that in the world it is reported in this resource specially. This fish named Hamoon mahi is one of the most economically valuable species in this region. Because of the recent years droughts, Hamoon logoon has been drive since 2000. Also, semi-wells (a semi natural resource) were affected drastically by recent drought years and their volume reduced to nearly one third of their real volume and resulted in changing at growth and reproduction physiology process in Schizothorax zanidnyi, brood stocks. Beginning of this project was done from October 2003. It's field studies begun (brood catching) since November 2001 by two methods including entangling gairs and at semi wells of Sistan that (Beach seine) had maximum rate of preparing qualified brood stocks. Broods transferred to Cyprinidea reproduction work shop of Zahak and after taking primary measures they stored in to the edaphic pools. Increasing the success safety factor (coefficient) for artificial reproduction of Sthizothorax zarudnyi , identifying the appropriate tune for Hormonal acceptance (physiological preparation of broods) is needed , so this important work was done regularly by histological studies and GSI measurements since November. Highest GSI rates of females (%80.51) and highest IV stage abundance of sexual maturity (%l 00) were observed an march. On the base of this date, Hormone therapy was done on broods on march. The used hormones are as follows Hypophysis. extraction, GnRHa and Anti Dopamin at the dozes of 3-6 ml, 20-30kg and 10-15 ml per kg body weight respectively and 2-3 times from 11-12-80 they were injected. Injected broods kept in to two circumstances, flow-through (rounded pool) and stagnant systems. In stagnant system 14 and 19 individuals of female and male (Schizothorax zauiulnri) broods, respectively injected in 11th, 15111, 19th, and 24th of march 1380. Non of the injected broods in 11 and 15 and 19th march (in stagnant Condition) answered to Hormone therapy. After final injection broods had general less activity and a few of them died. Mean temperature of brood pond waters (daily) which were injected. Fluctuated between 10-25-13. 63°c but injected broods on 24th march had different characteristics. They had pale color and had few fecundity. In this stage of injection they hadn't any successful vulation. After injection, Mean daily water temperature was 15, 88-17, 54°c. In Flowing system, 13-16 individual of males and females respectively were injected on 15th, 19th, 22th and 23th march. None of injected producers on 15th and 19th march with mean daily water temperature of 10, 25-12°c were prepared for spawning but injected producers on 22nd an 23th march with mean daily water temperature of 13.5-1 rc responded about 75-100 percent. (Schizothorax zarudnyi) brood stocks were prepared for spawning after 353-428 hours/day from final injection. Diameter of obtained eggs (before fertilization) was between 1.9-2.3 min and of fertilized eggs was 3.8mm. Fertilized eggs of (Schizothorax zarudnyi) were hatched after 6-7 days with mean water temperature of 17.08°c. Mean length of on one day larvae was 9.47 mm. Larvae was 9.47 mm. Larvae adsorbed the whole yolk sac after , 5-6 days at 17- 1°c and were prepared for releasing in to edaphic pools. Because of the lack of necessary and complementary facilities in the region , they had to release them in to veniros and growing them for 8 days. At the end of 18th day , 35000 larvae (at first) released into an edaphic pond with a volume of 150m2. After growing them for one moth , mean length and weight of new hatched larvae was 29.41 mm and 1.12►r , respectively. With respect to results of this investigation , artificial reproduction of (Schizothorax zarudnyi) Can be possible at 14-17°C and flowing water with Hormonal treatment. It -s breeding has increased development than other cultural specious in the region. Due to high economical value of this specious in Sistan and ti-s specialization east waters of Iran and having high resistance and proper growth There is a need of it's development and reproduction and culture in fish culture fanns (edaphic ponds• two-purpose pools) at the region and country.

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The article discusses the basics of cage and pen aquaculture. Factors to consider are: site selection; choice of nets, floats, frames, and anchors; and the choice of culture method.

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