红花荷天然林群落结构特征的研究

对从化石门国家森林公园的红花荷天然林群落进行了样地群落调查，测定了该群落的11种树种的重要值，并对群落的结构和动态进行了分析。结果表明，红花荷在群落中处于主要地位，红花荷群落稳定，天然更新良好，处于旺盛生长阶段。     

棉铃虫核多角体病毒基因组限制酶酶切分析及其多角体基因的定位

应用１１种限制性内酶ＢａｍＨⅠ、ＢｓｔＥⅡ、ＥｃｏＲⅠ、ＥｃｏＲⅤ、ＨｉｎｄⅢ、ＫｐｎⅠ、ＰｓｔⅠ、ＳａｌⅠ、ＳｓｔⅠ、ＸｂａⅠａⅠ和ＸⅠⅠ和ＸｈｏⅠ分别将中国棉铃虫核多角体病毒（单粒包埋ＨａＳＮＰＶ）湖北株基因组Ｄ组ＤＮＡ酶切为１０、１２、２２、２１、１３、６、６、４０、６、２１、６个片段，并求得基因组大小平均为１什什Ｍｒ≈７９．１×１０６．以家委核多角体病毒ＢｍＮＰＶ多角体基因为探针，利用Ｓｏｕｔｈｅｒｎ杂交技术将病毒多角体基因定位在ＳａｌⅠ４．２×１０３ｂ左右的片段上．与棉铃虫核多角体病毒其它株系酶切图谱比较结果表明，本株病毒与上海等株系及美洲棉铃虫核多角体病毒ＨａＳＮＰＶＥｌｋａｒ株系酶切图谱相似，它们之间的条带数和大小差异较小，而与已发现的所有多粒包埋型病毒ＨａＳＮＰＶ酶切图主谱差异较大．据此认为ＨａＳＮＰＶ和ＨａＭＮＰＶ属于基因型不同的两类病毒，而ＨａＳＮＰＶ不同分离株的同源性很高     

水环境中隐孢子虫和贾第鞭毛虫检测方法研究

我国最新《城市供水水质标准》(2005年6月)提出了关于隐孢子虫和贾第鞭毛虫的控制指标,但其推荐检测方法还没有产生.本文针对美国EPA1623检测方法中的3个关键步骤,在浓缩、分离和染色等过程中进行了相应的改进或替代,并对各种备选的方案进行了探讨和比较分析.结果表明,微孔滤膜过滤→乙酸乙酯福尔马林分离→改良抗酸 铁苏木联合染色具有较好的敏感性,操作简单且成本较低,适宜作为国内普通自来水厂的初级检测方法.图2表4参20     

Giving respondents time to think in contingent valuation studies: A developing country application

This paper evaluates whether the time given people to think about their responses to CVM valuation questions influences their answers. Our study was conducted in Nigeria as part of an evaluation of rural households' willingness to pay for public taps and private connections to improved drinking water systems. Respondents who were allowed time to evaluate the proposed water system bid significantly less than those who did not have that time. Moreover, this conclusion was upheld regardless of whether the water system was a public tap or a private connection.     

酸性硫酸盐土鳗塘水体防酸技术

为了克服生产实际中用石灰调节鳗塘水体酸性的弊端,利用石灰石石屑防御酸性物质入侵,效果特别好。水体pH维持在7～8的恒定水平;相关溶解氧含量也适合鳗鱼生长的需要:水草生长茂盛;经济效益可观。     

Grafting increases cadmium accumulation in the post-grafting generations of the potential cadmium-hyperaccumulator Solanum photeinocarpum

ABSTRACT

To determine whether grafting increases cadmium (Cd) accumulation in the post-grafting generation of hyperaccumulator plants, the effects of grafting on Cd accumulation characteristics of post-grafting generations of a potential Cd-hyperaccumulator Solanum photeinocarpum were evaluated in pot and field experiments. The following four grafting combinations were examined: ungrafted (UG), self-rooted grafting involving one S. photeinocarpum seedling (SG), self-rooted grafting involving two S. photeinocarpum seedling developmental stages (DG), and grafting on wild potato rootstock (PG). Grafting did not induce genetic changes in S. photeinocarpum, and increased the shoot biomass and the amount of Cd extracted by the shoots of the first, second, and third generations of S. photeinocarpum (PG > DG > SG > UG). Additionally, enhanced superoxide dismutase, peroxidase, and catalase activities and increased soluble protein contents of the first post-grafting generation were observed for the DG and PG, whereas only enhanced superoxide dismutase and peroxidase activities were observed for the SG. Grafting increased the DNA methylation levels by inducing hypermethylation in the first post-grafting generation (PG > DG > SG > UG). Therefore, grafting can enhance the Cd accumulation (phytoremediation) ability of post-grafting generations of S. photeinocarpum by enhancing DNA methylation levels, especially when wild potato rootstock is used.     

水体表面微层中酞酸酯的光降解研究

研究了水体表面微层中酞酸酯化合物光降解的动力学,指出光催化降解符合一级动力学过程,实验证明：催化剂ＴｉＯ２为２ｇ．ｌ＾－１,ｐＨ为６,并有Ｈ２Ｏ２存在时,是ＤＢＰ,ＤＥＨＰ光降解的最佳条件,溶解氧增加有利于光降解,实际表面微层水样的光催化降解速率比模拟水样快。     

宁南霉素诱导烟草酸性病程相关蛋白的研究

研究了宁南霉素对烟草酸性病程相关蛋白的诱导表达．结果表明，宁南霉素可系统性地诱导烟草叶片中酸性病程相关蛋白的高效表达．与水杨酸相比，宁南霉素诱导酸性病程相关蛋白的表达水平较高，持续时问较长．此外，在同一品种不同形态叶片烟草植株中，宁南霉素对植物酸性病程相关蛋白的诱导存在差异．图6表3参20     

AGA法及其在非线性数学模型参数估计中的应用

介绍了在基因算法基础上改进的加速基因算法（ＡＧＡ），并通过环境非线性数学模型参数估计实例对该法与传统参数估计方法进行了比较。初步结果表明，ＡＧＡ法直观、简便、拟合精度高、通用性强，易为广大环境工程技术人员理解和使用。     

Diets of the demersal fishes on the shelf off Iwate,northern Japan

Diets of demersal fishes were determined on the shelf (ca. 130 m deep) off Iwate, Japan. Samples were taken in three different types of habitat, an artificial reef (AR) site, a natural reef (NR) site, and sandymud bottom (SB) site, from May 1987 to September 1991, mostly every two months. A total of 67 prey items were recognized in the stomachs of 45 predator fish species. The most important preys were the pelagic fishes Sardinops melanostictus and Engraulis japonicus, which comprised 37% wet wt of the overall stomach contents. The percentage of pelagic fishes was highest at AR site, where fish density was highest. The dominant ten species could be divided into five feeding types. The pelagic fish feeders Physiculus maximowiczi and Gadus macrocephalus fed mainly on S. melanostictus. The dietary breadth of P. maximowiczi was wide, while that of Gadus macrocephalus was narrow. The pelagic crustacean feeder Theragra chalcogramma mostly consumed Themisto japonica and euphausiids and showed the least dietary overlap with other fishes. Benthic fish feeders were Hemitripterus villosus and Liparis tanakai. The benthic crustacean feeders Alcichthys alcicornis and Hexagrammos otakii consumed benthic crustaceans as well as pelagic and benthic fishes and showed the largest dietary breadth. The benthic invertebrate feeders Gymnocanthus intermedius, Dexistes rikuzenius and Tanakius kitaharai fed mainly on polychaetes and benthic crustaceans. But Gymnocanthus intermedius consumed a significant proportion of pelagic fishes. Ontogenetic dietary shift was recognized for these fishes. Pelagic fishes were consumed more intensively by larger individuals, especially true of A. alcicornis, Theragra chalcogramma and Gadus macrocephalus. Predominancy of the two most adundant species, P. maximowiczi and A. alcicornis, may be supported by their wide dietary breadth and the significant proportion of pelagic fish in their diets. Interspecific dietary overlap was low in most cases suggesting that food resources were well partitioned, although some high overlap was observed among the pelagic fish feeders, A. alcicornis, and Gymnocanthus intermedius, and among the benthic invertebrate feeders. Interspecific competition seemed more likely in the benthic invertebrate feeders than in the pelagic fish feeders partly because of superabundance of the pelagic prey S. melanostictus.