土壤水分与短期遮光对棉花光合及其气孔响应的影响

以陆地棉 (Gossypium hirsutum L.Zhongmain No.2 3)为供试材料 ,探讨了在充分供水-水分胁迫 -复水的处理过程中 ,短期不同遮光水平对棉花光合特性及其气孔响应的影响。结果表明 ,在水分处理过程中 ,所有不同遮光水平的棉花叶片对短期遮光具有相似的基本响应规律 :短期遮光使净光合速率迅速降低 ,气孔导度减少 ,但减少速率缓慢 ;遮阳网去掉后 ,叶片气孔重新开放速率和光合恢复被延迟。水分胁迫期间 ,所有遮光处理的水分利用效率均最高 ,但净光合速率均较低 ,光合及其气孔响应受到严重限制 ,遮光 75%受到的影响大于遮光 40 %的处理。复水后水分胁迫带来的残留影响仍然存在 ,结果使水分利用效率在整个水分处理过程中最低 ,遮光 75%的处理尤为明显。上述表明 ,土壤水分与短期遮光对棉花光合及其气孔响应的影响十分显著

论市场经济体制下自然资源的合理利用

论市场经济体制下自然资源的合理利用李法云，范志平（中科院沈阳应用生态研究所）一、计划经济体制下自然资源利用中存在的问题经济社会中的资源配置是指各种生产要素的优化组合，是自然资源与社会资源之间的协调；在计划经济体制下，由于没有形成标志资源稀缺性的合理价...

通过立法加强我国农业中农家肥资源的管理与利用

保持农业中农家肥养分资源的循环再利用是我国农业施肥的传统，在我国农业现代化进程中仍需努力保持这一传统，因为这不仅有利于农业中原有养分资源的充分利用，而且有利于提高化肥养分的利用效率，减少资源浪费和防止农业废料中养分进入环境导致农村和周边水体环境遭受污...

Thermodynamic behavior and applications of KMnO4 in cerium separation process using cyanex 923

In this work, studies were carried out on the extraction properties of Mn(II) and MnO4- in sulfuric acid medium using Cyanex 923. Effects of different variables on the extraction of Mn(II) and MnO4-, such as the concentrations of acid, the extractant, and the temperature, were investigated. Results indicated that Mn(II) was extracted weakly by Cyanex 923; however, MnO4- could be strongly extracted into the organic phase. The extraction mechanism of MnO4- was proposed, and the influence of MnO4- on the extraction of cerium was identified when KMnO4 as oxidizer added into the bastnasite sulfuric acid leaching liquor. As MnO4- was easier to be extracted into the organic phase than Ce(IV) and then lost its ability for oxidization, a new device was designed to realize sufficient oxidization of cerium from III to IV, and which has been applied to industrialization.

镧系络合物的双向螯合剂——BCPDA的性质研究

对镧系络合物的双向螯合剂——4,7-二氯磺酰基苯基-1,10-菲咯啉-2,9-二羧酸(BCPDA)合成、表征和性质研究表明:1.通过IR光谱、1H NMR、熔点、元素分析证明其结构正确。2.BCPDA可溶于几种不同溶剂。3.几种体系的BCPDA溶液所得到的吸收光谱基本相同,且BCPDA的浓度与吸光度在1.00-1.20×10~2μmol·L-1范围内呈正比。4.BCPDA标记蛋白质和铕离子与BCPDA螯合连接实验证实了BCPDA的双向功能。

ARYLIDENE COPOLYETHER SULFONES .1. SYNTHESIS AND CHARACTERIZATION OF SOME NEW COPOLYETHER SULFONES CONTAINING DIBENZYLIDENE CYCLOPENTANONE MOIETIES

New copolyether sulfones containing 2,5-bis(4-oxo-benzylidene)-cyclopentanone moieties were prepared in the conventional literature manner by condensing the dipotassium salts of 2,5-bis(4-hydroxybenzylidene)cyclopentanone (I) and 2,2-bis(4-hydroxyphenyl)propane (Bisphenol A, III) with 4,4'-dichlorodiphenyl sulfone (II), or by condensing the dipotassium salts of I with chlorine-terminated Bisphenol A-4,4'-dichlorodiphenylsulfone copolymers (V). The resulting copolyether sulfones were confirmed by IR, viscometry, DSC measurements, thermooptical analysis (TOA), and thermogravimetric analysis (TGA).

碱土金属复合氟化物体系中钐离子的价态及光谱

一定条件下钐离子、铕离子、镱离子等都具有明显的变价特性。钐离子通常以+3价形式存在,Sm~(3+)电子构型为[Xe]4f~5,基态光谱项为~6H_(5/2),4f能级最低激发态为~4G_(5/2)。Sm~(2+)在溶液中很不稳定,极易被氧化,但在某些固态化合物中Sm~(2+)能够比较稳定存在。通过适当的还原方法可以制得+2价钐的化合物。Sm~(2+)电子构型为[Xe]4f~6,基态光谱项为~7F_0,4f能级最低激发态光谱项为~5D_0。通常~5D_0能级位置较其4f~5d激发态能级下限位置低,因此室温

共价氢化物发生-光度分析法高选择性的研究与应用——Ⅰ.锗、砷、硒共价氢化物性质初探及其分别测定时其它氢化物干扰的消除

本文采用氢化物发生-银溶胶光度分析法探讨了GeH_4、AsH_3和H_2Se的性质,并利用共价氢化物气体分离柱分别建立了测定锗、砷时消除其它可生成氢化物元素干扰的简便、高效方法。测定1.0μg Ge(Ⅳ),5000μg As(Ⅴ)、Bi(Ⅱ)、Pb(Ⅰ)、1000μg Sb(Ⅱ)、Sn(Ⅰ)、500μg As(Ⅱ)和100μg Se(Ⅳ)、Sn(Ⅳ),Te(Ⅳ)不产生干扰。对砷的测定,其它共价氢化物元素的允许倍数分别为:Sb(Ⅱ)(5000)、Pb(Ⅰ)(5000)、Bi(Ⅱ)(5000)、Sn(Ⅰ)(1000)、Se(Ⅳ)(100)、Te(Ⅳ)(100)和Ge(Ⅳ)(15)。

An N-shape thermal front in the western South Yellow Sea in winter

An N-shape thermal front in the western South Yellow Sea (YS) in winter was detected using Advanced Very High Resolution Radiation (AVHRR) Sea Surface Temperature data and in-situ observations with a merged front-detecting method. The front, which exists from late October through early March, consists of western and eastern wings extending roughly along the northeast-southwest isobaths with a southeastward middle segment across the 20-50 m isobaths. There are north and south inflexions connecting the middle segment with the western and eastern wings, respectively. The middle segment gradually moves southwestward from November through February with its length increasing from 62 km to 107 km and the southern inflexion moving from 36.2A degrees N to 35.3A degrees N. A cold tongue is found to coexist with the N-shape front, and is carried by the coastal jet penetrating southward from the tip of the Shandong Peninsula into the western South YS as revealed by a numerical simulation. After departing from the coast, the jet flows as an anti-cyclonic recirculation below 10 m depth, trapping warmer water originally carried by the compensating Yellow Sea Warm Current (YSWC). A northwestward flowing branch of the YSWC is also found on the lowest level south of the front. The N-shape front initially forms between the cold tongue and warm water involved in the subsurface anti-cyclonical recirculation and extends upwards to the surface through vertical advection and mixing. Correlation analyses reveal that northerly and easterly winds tend to be favorable to the formation and extension of the N-shape front probably through strengthening of the coastal jet and shifting the YSWC pathway eastward, respectively.

中国典型海域超微型生物生态学初步研究

通过流式细胞技术(FCM)调查了我国东海、南海和胶州湾的几类超微型浮游生物，包括聚球藻(Synechococcus)，原绿球藻(Prochlorococcus)，超微型真核生物和异养细菌的空间分布、季节变化及与环境因子之间的关系。开展了一系列现场实验对几种常量和微量营养元素对4类超微型浮游生物生长的影响进行了初步的研究。另外，对细胞周期法估计原绿球藻的生长率，以及用流式细胞仪分析病毒粒子的数量分布做了尝试性的工作。主要结果如下： 1 在东海黑潮区，超微型浮游植物约占叶绿素生物量的60％多，在其它海区，约占10-40％。原绿球藻的季节变化较大，冬季主要分布在黑潮流域，夏季可达50米等深线附近。在黑潮区，原绿球藻与聚球藻细胞密度的比值在10左右，在其它海区，比值为1-2。超微型浮游生物群落结构从沿岸到外海变化较复杂。在南海，平均70％多的叶绿素生物量由超微型浮游植物提供，而原绿球藻则为超微型自养浮游生物碳生物量的主要贡献者，平均约占30％。整个南海在海水性质上接近贫营养大洋海区，原绿球藻和聚球藻的细胞密度比为15～160，海盆区和岛礁区超微型浮游生物群落结构有所差别。 超微型浮游生物的分布和群落结构在两个海区均受海流、水团及水柱理化性质的影响。总的看来，海流、水团的性质越接近大洋，超微型浮游生物在生态系统中的地位相对越重要，而原绿球藻在生物量和生产力上的相对贡献也越大。原绿球藻在东海的分布除受水流、水团的作用外，在冬季还受温度的限制。冬季原绿球藻大体限于黑潮流域，而夏季则可分布到50米等深线附近。从大尺度范围看，从近岸到外海，或从中营养海区到贫营养海区过渡的过程中，原绿球藻和异养细菌的丰度变化呈相反趋势，它们与聚球藻之间的变化趋势因海区的不同而存有差异，这可能是由于多品系聚球藻同时存在的原因。这些相关性在水质条件变化幅度剧烈的东海表现得显著，而在海水水质条件差别不大的南海则不明显。在垂直分布上，超微型浮游植物的分布与水柱的分层、营养状况都有关系。在上混合层较浅，硝酸盐在检测限以上的东海大部分海区，超微型浮游植物的最大层与硝酸盐跃层深度有关，而在上混合层较深，混合层中硝酸盐的浓度低于检测限的南海海盆区，原绿球藻的高值分布似乎与氨氮的浓度有关。小尺度范围内超微型浮游生物的数量和群落结构的变化不仅与温度，营养盐浓度有关，还与水柱的物理结构(如混合层发育的情况)有关。 2 南海营养盐添加实验表明，原绿球藻似乎更受磷限制，而聚球藻和超微型真核生物对铵氮的添加反应更明显。在生理上，原绿球藻与聚球藻和超微型真核浮游植物有明显差别，后两者对营养盐添加的反应接近。原绿球藻对钴添加的反应大于铁添加的反应，而后两者则对铁添加的反应较强。在某些营养生理特性上，原绿球藻似乎更接近异养细菌。 75米层海水铁添加实验表明，不同浓度的铁均促进nano一级的浮游植物的生长；对于超微型浮游植物来说，纳摩尔级铁的添加有利于超微型真核生物的生长，而更高浓度的铁添加则对聚球藻和原绿球藻的生长有利。 虽然钴的加入有利于原绿球藻的生长，但是维生素B_(12)的加入对其生长无明显的影响，说明钴在原绿球藻的生理代谢过程中可能有合成维生素B_(12)以外的作用。钴的添加对聚球藻的生长无明显影响，但不同浓度的维生素B_(12)的添加均能促进聚球藻的生长，说明火洋中的聚球藻品系可能不能自己合成该种维生素。无论是钴还是维生素B_(12)对超微型真核生物的生长均无显著的影响。 钼与铁均参与硝酸盐的还原和固氮作用，但钼的添加只对聚球藻有明显的促进作用，对其它几类超微型浮游生物的影响不明显。 3 现场培养实验表明，原绿球藻在生理上能耐受的温度下限比其自然分布的温度下限更低，说明冬季限制原绿球藻向近岸分布的是多种环境因子共同作用的结果。实验表明，种间相互作用，微量金属元素，以及水体的物理化学条件等都是制约原绿球藻近岸分布的因素。 4 细胞周期法估计南海75米层原绿球藻的生长率为0.54／天。 5 流式细胞仪在东海东部检测一类病毒粒子的数量在10~5／毫升的数量级。尽管这类病毒粒子在垂直分布上与自养细胞的分布有关，但是在水平分布上却与异养细菌数量的变化相关性最显著。 6 胶州湾超微型浮游植物主要出聚球藻和超微型真核生物组成。聚球藻的细胞浓度在夏季最高，冬季细胞浓度最低，平均为1.4 8*10~3细胞／毫升，并与温度变化的关系最明显。超微型真核生物细胞浓度的季节变化不如聚球藻规律。从全年变化的角度来看，超微型浮游植物在胶州湾生态系统中占有重要的地位，而超微型真核生物是超微型浮游植物生物量的主要提供者。

Feeding level-scaled retention efficiency, growth and energy partitioning of a marine detritivorous fish, redlip mullet (Liza haematocheila T. & S.)

The effects of feeding level on growth, retention efficiency, faeces production and energy partitioning of redlip mullet were studied. A practical diet was used and fed at six levels from starvation, 1%, 2%, 3%, 4% of body weight (BW) to satiation for 3 weeks. The temperature was kept at 24 +/- 1 degrees C. Reducing the feeding amount resulted in significantly lower weight gain, and retention efficiency was significantly affected by feeding levels and attained the maximum at maximum feeding intake. Feeding 2% BW was the minimum required for fish to maintain growth. Fish carcass composition under different feeding levels could be divided into three groups: (1) starvation and FL1; (2) FL2 and FL3 and (3) FL4 and satiation, with significant differences among the groups but no differences in the groups except that ash content remained at constant value. Body composition of fish of group 2 was close to initial fish. The thermal-unit coefficient was 0.0381 at satiation, and significantly increased with increasing feeding levels. In order to accurately estimate basal metabolism (HeE), another trial on the relationship between HeE (kJ) and BW (g) was carried out. An exponential curve as HeE=0.1255BW(0.8386) explained this relationship. Intake energy (IE) increased from 11.30 to 63.08 kJ per fish, matching with different feeding levels. Energy allocated to growth of IE decreased with reducing feeding amount. There was a linear relationship between metabolism energy and retention energy in percentage.

菊科千里光族款冬亚族的花粉超薄结构及其系统学意义

研究了国产菊科千里光族款冬亚族及其相关类群 1 1属 1 5种植物的花粉超薄结构。研究类群的花粉超薄结构可分为 2类 :“千里光型”和“向日葵型”。多榔菊属、大吴风草属和毛冠菊属为“向日葵型”,其余种类均为“千里光型”。根据花粉超薄结构类型 ,结合其它有关方面的研究 ,认为大吴风草属与橐吾属并不近缘 ,而毛冠菊属可能接近于紫菀族。