971 resultados para 12930-048


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利用发根农杆菌(Agrobacterium rhizogenes)1601,1000,1500,15834,A4,均成功地转化了中药青蒿(Artemisia annua L.)并且建立了pRi1601,pRi15834,pRiA4诱导的发根培养。pRi1601,pRi15834的发根诱导率比其它质粒高。太老或太幼的叶片不利子发根的诱导;发根主要从叶脉的伤口处萌发;带顶芽或带侧芽的叶片容易诱导根,但不一定是发根。光照有利于发根的诱导和发根的生长。以每个发根的“绝对生长速率”(Gtowth Ratio,GR)和绝对“侧根”数量(Number of Side Roots,NSR),通过大量的发根系的筛选,建立了8个发根系,1601-L-1, 1601-L-2, 1601-L-3, 1601-L-4, 15834-L-1, 1601-P-I, 16 01-P-2,15834-L-2。Southern分子检测表明,160l-1-1,1801-L-2, 1601-L-3,1601-L-4,1601-P-1,1601-P-2均为转化子。8个建立的发根系之间无论生长或者QHS的合成存在明显的差异。比较光/暗(16/8hrs),25℃条件下培养的16 01-L-1,1601-L-2,1601-L-3,1601-L-4,1601-P-l,和1601-P-2,其中16 01-L-3的生长最快,160l-L-1的生长最慢;但是,1601-L-1的QHS的含量最高(可达1. 048%),1601-1-3的QHS的含量最低。160Z-L-3,15834 -L-1和2583:1-L-2的生长速率相差不大。用盛有l000mLMS液体培养基的3000mL的锥形瓶扩大培养1601-L -3,15834-L-1和15834-L-2,转速为ll0rlpm,培养过程中发根容易形成发根球(Hairy Root Balis,HRB),HRB的形成严重影响发根的生长和QHs的合成,HpLC分析表明扩大培养发根中QHS的含量比较低。 改变MS基本培养基中的无机离子的浓度,研究不同无机离子对发根生长和QHS的合成的影响。 l、KN03为18.79×10-3M时有利于1601- L-1生长,为14. 84×10-3M时有利于QHS的合成。NH-4N0-3浓度在10.93-12. 49×10—3M范围内有利于1601-L-1生长,在0-20.62×10-3M范围内对QHS的合成影响不大,大于20. 62×lO-3M不利QHS的合成。培养基中NH-4+/N0-3-比值为0. 37-0. 4-0.52:1时有利于发根的生长,比值为0.52 - 0.58:1时有利于QHS的合成。 2、H-2P0-4-浓度为2.498×10-3M时有利于发根的生长在0-2. 498×l0-3M范围内,随着浓度的提高,促进发根的生长。培养基中的H2P4 -的浓度在0-1.249×lO-3M的范围内,随着浓度的提高,促进QHS的合成,为1.249×10-3M时QHS的含量最高。 3、培养基中最适16 01-L-1生长的Ca-2+浓度为0.198- 0.766×10-3M,大于或小于该浓度范围,显著地抑制发根的生长。但是,在0-3.695×10-3M范围内,随着培养基中Ca-2+浓度提高,促进QHS的合成,最适Ca-2+浓度为3.695×l0-3M。 4、培养基中不加Mg-2+时,完全抑制发根生长,在0. 142×10-3M-7.506×l0-3M浓度范围内,对发根生长影响没有明显的差别。但是,HPLC和UV分析发根中QHS含量,培养基中不加Mg-2+时,发根中QHS含量最高。 5、培养基中的Fe-2+浓度在0. 25 -1.0×10-3M范围内,同时有利于16 01- L-1的生长和QHS的形成。 6、培养基中最适合予16 01- L-3生长的KI浓度为2.5ppm,大于或小予该浓度均显著地抑制发根的生长,培养基中加入KI明显地降低发根中的QHS的含量。 7、H2BO3对l601-L-l生长影响不大,HPLC分析QHS的含量,培养基中的H3BO3浓度为100ppm和400ppm,QHS的含量分别为1.69mg/g和1.80mg/g(DW)。 8、Cu-2+对1601-L-3的生长影响显著,最适合1601-L-3生长的Cu-2+浓度为1.00ppm,在0 -1.00ppm的浓度范围内,随着培养基中的Cu+浓度的提高,发根的生物量不断增加。培养基中QHS合成的最适Cu2+浓度为0.05ppm,大于或小于该浓度均显著地抑制发根中QHS的合成。 比较光培养和暗培养对发根生长的影响,结果表明光照明显地促进1601-L-l的生长,暗培养明显不利于发根的生长。最适合于发根生长的温度为25℃,大于35℃显著地抑制发根的生长,影响发根的根尖细胞的正常分裂。 改变培养基中的蔗糖浓度和在发根培养的不同时期给培养基中添加蔗糖,试验结果表明蔗糖作为碳源对1601-L-3和1601-L-1的生长具有显著的影响。 (1)培养基中缺少蔗糖显著地抑制发根的生长。 (2)发根培养的前5天时间内,蔗糖浓度为30- 60glL昀培养基最有利于发根的生长,50glL的培养基中的发根生长最快,培养基中的蔗糖浓度大于60g/L小于30g/L时,发根的生物量增加较少。 (3)发根培养至第15天时,蔗糖浓度为60g/L的培养基最有利予发根的生物量的增加。发根培养至30天时,蔗糖浓度为60-90g/L的培养基,发根的生物量的增加相差不大,但是为蔗糖浓度为30-40g/L的培养基中的发根生物量一倍。 (4)发根培养过程中,分别于第5和15天给蔗糖浓度为30g/L的培养基中添加一次或二次蔗糖,使培养基中的蔗糖终浓度相当于60g/L或90g/L,培养至30天时,添加蔗糖的培养基中的发根的干重生物量相当于不添加蔗糖培养基中的发根生物量一倍,相当于初始蔗糖浓度为60g/L和90g/L培养基中发根的生物量。 (5)随着培养基中蔗糖浓度的提高,发根干重/鲜重比显著增加。培养基中的蔗糖的消耗量与发根生物量的增加呈正相关,蔗糖消耗越多,发根生物量的增加越大。 比较pH值对发根生长和QHS合成的影响表明,灭菌前pH值在5.O-6.5范围内的培养基适合予1601-L-1的生长,小于5.O不利于发根的生长,pH5.8有利于1601-1-1生长和QHS的生物合成。发根收获时培养基中的pH值一般为4.5-5.2. pH7.O抑制发根的生长,pHl0.O对发根具有强烈的致死作用。发根在培养过程中,对培养基中的pH值具有显著的调节作用,发根能在很短的时间内(24- 48hrs)使pl:l值为5.8、6.4、7.0培养基降低到pH4. 5-5.2,pH为5.8的培养基有利于QHS合成。 比较不同基本培养基对发根生长和QHS合成的影响,试验结果表明N6、DCR、Litvay培养基有利于1601-L-1的生长,WS、White、B5培养基不利于发根的生长。DCR培养基中的QHS含量最高。 根据三水平试验选用三水平正交表来安排试验的原则,选用三水平正交表L7(3-),研究多因子效应对发根生长和QHS合成的影响,试验结果表明,Mg2+,Fe2+,Mn-2+,NH4NO3,KN03 ,KI,Ca-2+为发根生长的主要因子,NH4N03,KNOs,Mg2+,Ca2+,肌醇为QHS合成的主要因子。 通过TLC分析发根中QHS和其它化学成分,同时比较发根和无菌苗及野生植株的化学成分,发根和无菌苗均能合成包括QHS在内的野生青蒿叶片中的大部分非挥发性的化台 物。 研究青蒿植株在发育过程中QHS的含量的变化以及发根、无菌苗和野生青蒿中QHS的合成,HP分析结果表明,l、不同的单株青蒿之间的QHS量相差很大。2、同一植株幼 叶的QHS含量比老叶的QHS含量高。3、不同单株青蒿之间达到最高QHS含量的时间不一样,开花期或开花之前。4、无菌苗(带根)或者不带根丛生芽均能合成QHS,但是带根的无菌蕾的QHS量比丛生芽中的QIS的含量高。5、不同发根农杆菌转化的发根系1601-L-1和15834-L-1都能合成QHS。

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Stock structure of eastern Pacific yellowfin tuna was investigated by analyzing allozymes and random amplified polymorphic DNAs (RAPDs) from 10 samples of 20–30 individuals each, collected between 1994 and 1996 from fishing vessels operating in the Inter-American Tropical Tuna Commission (IATTC) yellowfin regulatory area (CYRA). Allozyme analysis resolved 28 loci, eight of which were polymorphic under the 0.95 criterion: Aat-S*, Glud, Gpi-F*, Gpi-S*, La, Lgg, Pap-F*, and 6-Pgd, resulting in a mean heterozygosity over all allozyme loci of H = 0.052. Four polymorphic RAPD loci were selected for analysis, resulting in a mean heterozygosity of H = 0.43. Eight of 45 pairwise comparisons of allozyme allele frequencies among the ten samples showed significant differences after correction for multiple testing (P<0.0001), all of which involved comparisons with the Gulf of California sample. Confirmation of this signal of population structure would have management implications. No significant divergence in RAPD allele frequencies was observed among samples. Weir and Cockerham θ estimated for allozyme loci (θ=0.048; P<0.05) and RAPD loci (θ=0.030; P>0.05) revealed little population structure among samples. Mantel tests demonstrated that the genetic relationships among samples did not correspond to an isolation-by-distance model for either class of marker. Four of eight comparisons of coastal and offshore samples revealed differences of allele frequencies at the Gpi-F* locus (P<0.05), although none of these differences was significant after correction for multiple testing (P>0.001). Results are consistent with the hypothesis that the CYRA yellowfin tuna samples comprise a single genetic stock, although gene flow appears to be greater among coastal samples than between coastal and offshore samples.

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In this project sampling was done from 9 stations in 3 depths during 5 seasons to separate, identify and examine the biodiversity of cyanobacteria. Another sampling also has been done to analyse all physical and physicochemical parameters, primary production and polluting agents such as heavy metals and oil hydrocarbons in water and sediments. Along with optimization of Oscillatoria to study the ability of producing natural substances, these cyanobacteria were analysed from the point of antimicrobial and mutagenic effects. To examine the relationships among analysed parameters, the regression test, analysis of varian and Post Hoc were used. As the result of this study 48 genus of cyanobacteria were pecognised among which 35.5% were croco ccales and 64.4% were Hermogonals. Oscillatoria was one of the Filamentous cyanobacteria which had antibacterial and mutagenic effects. The results of multicommunity consistency varians test, post Hoc and homogenous subsets show significant difference between biodiversity of cyanotbacteria in coral ecosystem, Mangrove and transite. The linear correlation coefficient between biodiversity of cyanobacteria and bioenvironmental agents were examined, but there was no continuous relation between these factors and biological biodiversity. In Surface layer there was a significant correlation coefficent at 0.048 and probability at 95% confidence interval. Also, the biodiversity is depended on oil pollution and heavy metals such as copper (Cu) and chromium (Cr).

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采用体长频率法和瞬时生长率法对后湖湖球蚬Sphaerium lacustre的周年生产量进行了测算. 结果表明两种方法得到的生产量较为吻合.生产量的带壳湿重和去壳干重分别是体长频率法1.048 g/(m2a) 0.0599 g/(m2a); 瞬时生长率法1.178 g/(m2a), 0.0673 g/(m2a).对应的P/B系数为3.23.4.

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The structural and optical properties of InAs layers grown on high-index InP surfaces by molecular beam epitaxy are investigated in order to understand the self-organization of quantum dots and quantum wires on novel index surfaces. Four different InP substrate orientations have been examined, namely, (1 1 1)B, (3 1 1)A, and (3 1 1)B and (1 0 0). A rich variety of InAs nanostructures is formed on the surfaces. Quantum wire-like morphology is observed on the (1 0 0) surface, and evident island formation is found on (1 1 1)A and (3 1 1)B by atomic force microscopy. The photoluminescence spectra of InP (1 1 1)A and (3 1 1)B samples show typical QD features with PL peaks in the wavelength range 1.3-1.55 mu m with comparable efficiency. These results suggest that the high-index substrates are promising candidates for production of high-quality self-organized QD materials for device applications. (C) 1999 Elsevier Science B.V. All rights reserved.

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本文以探讨土壤优先水流的特征和非吸附性离子优先先移为主要目的,通过对土壤优先水流穿透曲线的分析,定量的论证了优先水流的特征。在分析方法上进行了一系列尝试。得出了土壤优先水流的几个典型特征,即土壤优先水流的优先穿透、穿透曲线的不对称性、穿透曲线的拖尾和出流速率的不稳定性。在土壤优先水流特征分析的基础上,提出了判断土壤优先水流的定量方法。围绕非吸附性离子的优先迁移的实验结果,分析了阶跃输入和脉冲输入的非吸附性离子在不同水力负荷下的运移特点、优先水流的侧向入渗对土体中溶质分布的影响和耕作对土壤优先水流及溶质运移的影响。研究表明原状黑土、棕壤、暗棕壤和红壤中优先水流穿透时的孔隙容积分别为 0.05、0.051、0.048 和 0.042,穿透浓度为 0.759mg/l、0.087mg/l、0.115mg/l 和 0.117mg/l,在穿透时间上分别较对应的填充土柱提前 144、104、168 和 120 小时。原状土柱出流速率波动较大,其变异系数分别较对应的填充土柱高出 5~10 倍。在不同水力负荷下,原状土柱 Br 和 NO_3~- 的累积迁移量均明显高于填充土柱。不同水力负荷条件下,Br 和 NO_3~- 累积迁移量的差异不是来源于土壤优先水流,而是来源于土壤基质流。耕作可以影响土壤优先水流的穿透规律,并对土壤溶质运移构成影响。但耕作对土壤优先水流的穿透时间、穿透时的孔隙容积、穿透峰的出现和累积迁移量的影响并不遵从同一规律,这个过程不能通过孔隙的增减来简单描述的。优先水流存在下, Br 和 NO_3~- 在土壤中的分布表现为以大孔隙为中心向外径向递减,即 I 区溶质含量 > II 区 > III 区。土柱中溶质的径向分布以大孔隙为中心呈辐射状,表现距大孔隙越近溶质浓度越高。土壤优先水流可以引起非吸附性离子的快速大量迁移。这种迁移为深层次土壤和地下水中溶质浓度的大幅度提高提供了条件,一方面可能增加了深层次土壤污染修复的难度,一方面可以导致水体的富营养化,造成在下水污染的危险。

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采用野外调查与室内培养相结合的方法,研究了我国北方半干旱区科尔沁沙地退化草地营造樟子松人工林32年后0~10cm表层土壤理化性状、土壤碳氮矿化量、土壤微生物量以及土壤酶活性等的变化.结果表明:32年生樟子松人工林土壤有机碳、全氮和全磷等养分含量分别下降了21%、42%和45%;5月和11月樟子松人工林土壤NH4+-N显著高于草地(P=0.001;P=0.019),而5、8和11月草地土壤NO3--N含量显著高于樟子松人工林(P<0.001;P=0.048;P=0.031);5、8和11月樟子松人工林土壤有机碳日矿化释放的CO2-C量均大于草地,而二者土壤氮矿化率差异不显著(P>0.05);5和8月樟子松人工林土壤微生物量碳含量与草地相比差异不显著,11月则显著高于草地;土壤养分和水分含量是影响土壤微生物量碳含量的重要因素;与草地相比,樟子松人工林土壤脲酶和蔗糖酶活性降低,而土壤过氧化氢酶活性升高.上述结果说明半干旱区沙质退化草地营造樟子松人工林32年后土壤质量出现一定程度的下降;由于植被的改变,樟子松人工林土壤理化性状和生物学性状等表现出与草地不同的季节动态特征.造林作为我国北方半干旱区沙地退化生态系统的一种恢复手段具有一定的局限性.

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(C5H9C5H4)(3)NdBrLi(THF)(4)(1)(C5H9=cyclopentyl) was obtained from the reaction of NdCl3 with C5H9C5H4Na and LiBr (Nd:Na:Li=1:2:1 molar ratio) in THE X-ray crystallography showed that the ten-coordinated neodymium atom is bonded to three cyclopentylcyclopentadienyl(eta(5)) rings and a single bromine atom bridging a lithium which is bonded to three THF molecules. Complex 1 is triclinic, P1 space group with unit dimensions of a= 12.048(2), b= 13.498(3), c= 13.831(3)Angstrom, a = 104.16(3), beta = 104.07(3), gamma =95.96(3)degrees, V=2083.3(7)Angstrom(3), Z=2, D-c=1.35Mg/m(3) and F(000)=874. (C5H9C5H4)(3)SmTHF (2) was synthesized by reaction of anhydrous SmCl3 with C5H9C5H4Na at a molar ratio of 1:3. The structure was determined by X-ray crystallography. The ten-coordinated samarium atom is bonded to three cycloperrtylcyclopentadienyl rings and one oxygen of THF molecule to form a pseudo-tetrahedron. Complex 2 is orthorhombic, Fdd2 space group with unit cell dimensions of a =28.175(5)Angstrom, b =46.24(2) Angstrom, c =9.167(4) Angstrom(3), V=11943(8)Angstrom(3), Z= 16, D-c = 1.38Mg/m(3) and F(000)=5136.

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无水三氯化钕与环戊烷基环戊二烯钠、溴化锂(1:2:1摩尔比)反应,除去不溶物和溶剂后,产物在己烷/四氢呋喃溶剂中冷冻得到兰紫色晶体(C5H9C5H4)3NdBrLi(THF)3(配合物1)。其中心金属Nd3+的配位数为10,以η5与3个环戊二烯基相连,并通过单溴原子桥连锂原子,形成双核结构。该晶体属三斜晶系,P`1空间群。晶体学参数为a=12.048(2)、b=13.498(3)、c=13.831(3);α=104.16(3)、β=104.07(3)、γ=95.96(3); V=2083.3(7)3、Z=2、Dc=1.35Mg/m3、Mr=847.01gmol-1、F(000)=874。无水三氯化钐与环戊烷基环戊二烯钠(1:3)反应,产物在-30oC下的己烷溶剂中结晶得桔红色晶体(C5H9C5H4)3SmTHF(配合物2)。该晶体属正交晶系,Fdd2空间群。晶胞参数a=28.175(5) 、b=46.24(2)、c=9.167(4);V=11943(8)3、Z=16、Dc=1.38Mg/m3、 Mr=622.11 g·mol-1、F(000)=5136。10配位的金属Sm3+与3个环戊二烯基以η5相连,并结合...

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A novel layered compound, [Ni(C10H8N2)(2)V3O8.5], was hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 1.551 8(3) nm, b = 1.476 1(3) nm, c = 1.048 3(2) nm, beta = 92.02(3), V = 2.399 8(8) nm(3), Z = 4, R = 0. 046 7, wR(2) = 0. 085 9.

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[PrAl (CF3COO)(2) (CF3CHOO) (C2H5)(2) (C4H8O)(2)](2) M-r = 1420. 56, monoclinic, P2(1)/n, a = 10. 651 (6) , b = 24. 276(9), c = 11. 110(5) Angstrom, beta = 107. 650 (4)degrees , V = 2737. 4(1) Angstrom (3) , Z = 2, D-c = 3. 45 g/cm(3) , F(000) = 2816 , T = 233K, MoK alpha radiation (lambda= 0. 71069 Angstrom), mu(MoK alpha) = 38. 017 cm(-1) , R = 0. 048 for 2847 observed reflections (I greater than or equal to 3 sigma(I)). It is isostructural with [LnAl (CF3COO)(2) (CF3CHOO) -R-2 (C4H8O)(2)](2) (Ln = Ho, R = Et; Ln = Ndt Y, R = Bu-1). Pr3+ is coordinated by eight oxygen atoms from five bridging ligands and two THF forming a distorted bicap-prism.

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CH_3C_5H_4LnCl_2·2LiCl·nTHF与2mol的LiNPh_2在THF、已烷和甲苯混合液中反应,经DME萃取,得到[Li·(DME)_3][(η~5-CH_3C_5H_4)Ln(NPh_2)_3](Ln=La,Pr,Nd)。对其进行了元素分析、IR和NMR表征。镧配合物单晶结构测定表明,属单斜晶系,P2_1/a空间群,晶胞参数为α=1.7461(6)nm,b=1.6576(5)nm,c=1.8335(6)nm,β=96.04°,V=5.277um~3,Z=4,D_c=1.26g/cm_3,R=0.057,R_w=0.048。该配合物是一个离子对,La-N和La-C(环)键的平均距离分别为0.2459(8)和 0.2843(11)nm。稀土离子形成一个六配位的扭曲四面体。

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A Kalman filter was developed for resolving overlapping lines in inductively coupled plasma atomic emission spectrometry (ICP-AES) and evaluated experimentally with the determination of La in the presence of Ho, and Cu in the presence of Pr. The whiteness of the innovation sequence for an optimal filter was explored to be the criterion for the correction of the wavelength positioning errors which may occur in spectral scans. Under the conditions of the medium-resolution spectrometer and 1.5 pm step size in scans, the filter effectively resolved the Cu/Pr line pair having a small peak separation of 4.8 pm. For the La/Ho line pair with a peak distance of 9.8 pm, an unbiased estimate for La concentration was still obtained even when the signal-to-background ratio was down to 0.048. Favourable detection limits for real samples were achieved. Unstructured backgrounds were modeled theoretically and all spectral scans therefore did not require the correction for solvent.

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本文报导了(Cp_2ErCl(THF)]_2的晶体结构,晶体属单斜晶系,P2_1/c空间群。晶胞参数为a=8.141(2),b=21.218(6),c=8.597(2),β=107.77(2)°;V=1414.1(6) ~3;Z=2,D_c=1.90g/cm~3,F(000)=780,μ_c=66.3cm~(-1)(MoK_a)。最终的偏离因子R=0.047,R_(to)=0.048。结构分析表明,该配合物是以两个氯离子与金属离子桥联的二聚体形式存在。四氢呋喃中的氧原子同金属离子键合,Er—O键长为2.490(6),两个环戊二烯中的所有碳原子同金属离子间的平均键长为2.649,Er-Cl=2.666(3),Er—Cl-a=2.797(3),Er-Er_a=4.42,Cl-Er-Cl_a键角为72.2°。

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滤食性贝类以水体中的浮游植物和有机碎屑为主要食物,养殖海域的初级生产力水平、水动力学特性等生态环境因子的差异,不仅直接影响养殖贝类的产量,而且也与贝类养殖活动对生态环境的压力密切相关。由于养殖的种类、密度、方式及养殖海域的特性不同,关于贝类对生态环境的影响往往有不同的结果。本文以我国北方大连獐子岛扇贝底播海区和荣成桑沟湾贝类筏式养殖区为研究对象,采用现场调查、室内受控实验及生态数值模型模拟方法,分析研究了滤食性贝类对海域生态系统的影响,对这两个海域贝类养殖的生态容量进行了初步的评价。 主要结果: 1. 獐子岛海域底播贝类养殖活动对该海域生态系统的影响较小。非参数统计—符号检验的结果显示,养殖区与非养殖区之间的溶解性无机氮、磷酸盐浓度、氮磷摩尔比及浮游植物群落结构没有统计学上的差异(p>0.05)。但是从变化的趋势上来看,贝类养殖活动对水域环境的某些参数有一定程度的影响。例如,獐子岛底播贝类养殖海域的溶解性无机氮以氨氮为主,可能与贝类的代泄活动有关;不论是叶绿素浓度,还是网采浮游植物的生物量都是贝类高密度养殖区<贝类低密度养殖区<非养殖区(7月份除外),这种趋势可能与贝类的摄食压力有关。 桑沟湾各环境指标表现出明显的区域性。除春季外,非养殖区的DIN浓度高于各养殖区。在春季和冬季,贝类区的磷酸盐浓度显著降低;而硅酸盐浓度在夏季和秋季显著增大。综合分析DIN、PO4-P及SiO3-Si三个参数的四季变化,海带区、贝藻区及贝类区发生显著性变异的概率分别为25%,42%和50%,贝类区的变异较大。浮游植物、小型浮游动物的生物多样性指数都是以非养殖区为最高,贝类区的多样性指数最低。尤其是浮游动物的丰度,贝类区显著低于非养殖区。 2. 利用挪威的MOM (Modelling-Ongrowing fish farms-Monitoring)评价系统,评价了桑沟湾长期大规模的贝藻筏式养殖活动对底质环境的压力。在桑沟湾设10个取样站位,共获得66个底泥样品。比较了MOM-B评价系统的3组参数的季节变化特性。结果显示,底质条件属于1级,说明桑沟湾贝藻长期大规模的养殖活动对底质环境的压力较低。结合桑沟湾的环境及养殖特点,分析了压力较低的原因。 3. 经计算,2006年中国海水养殖的贝类和藻类使用浅海生态系统的碳可达396万吨,并通过收获从海中移出至少136.9万吨的碳。从1995年至2006年,养殖大型藻类和贝类累计移出的碳分别约为365万吨和893万吨,总计达1258万吨。证明了浅海的贝类和藻类养殖活动直接或间接地使用了大量的海洋碳,提高了浅海生态系统吸收大气CO2的能力。 4. 采用模拟现场生物沉积法测定了虾夷扇贝的滤水率、摄食率等生理指标及其与贝类个体大小、水温的关系。虾夷扇贝单位个体的滤水率与组织干重的关系符合幂函数方程CR=a×DWb,b值在0.45~0.65范围内;水温对虾夷扇贝滤水率的影响极其显著(p<0.01),温度(T)与滤水率(CR)呈抛物线的关系:CR=-0.0009T2+0.0188T-0.0306,水温为10℃时,虾夷扇贝的滤水率、摄食较大。 5. 采用模拟现场流水法测定了3种滤食性贝类的食物选择性。紫贻贝、长牡蛎及栉孔扇贝分别对直径4m, 6m 和 8m颗粒的保留效率达到最大值;对小颗粒(直径2m)的保留效率分别为17%, 19% 和 8%。栉孔扇贝对食物数量和质量浓度的变化相对敏感,随着数量浓度的增加,栉孔扇贝倾向于摄食较大的颗粒;随着颗粒食物质量浓度的增加,倾向于摄食较小的颗粒。 6. 獐子岛海域四个航次的调查结果显示,叶绿素浓度在1.23~2.85mg.m-3范围内,均值为1.78±0.57 mg.m-3;初级生产力的变化范围为30.4~117.0 mg C. m-2.d-1,平均值为76.6±41.9 mg C. m-2.d-1。通过虾夷扇贝生物量断面调查,获得了虾夷扇贝的壳高频率分布情况,7月份的众数值出现在100 mm,10月份壳高的众数值为80 mm。利用以上测定的虾夷扇贝的滤水率等基本生物学特性,结合虾夷扇贝的年产量、海域面积和有关的水文状况等数据,计算了滤水效率、摄食压力、调节比率3个食物限制性指标参数,全年的均值分别为0.048, 0.31和 0.16,都小于1,说明目前该海域虾夷扇贝的养殖量未达到养殖容量。 7. 利用STELLA软件,建立的桑沟湾贝藻养殖的数值模型,模拟了叶绿素a浓度及氮磷营养盐的周年变化情况,及其对贝类养殖生物量变化的响应。以叶绿素a浓度为指标,初步探讨了桑沟湾贝类的生态容量。