CHLOROPHYLL-BIOMASS-NUTRIENT RELATIONSHIPS FOR NATURAL ASSEMBLAGES OF FLORIDA PHYTOPLANKTON1

Parallel determination of phytoplankton biomass and chlorophyll a concentration were made on spring and summer phytoplankton samples collected from 165 Florida lakes. There was a significant correlation between chlorophyll a concentration and phytoplankton biomass (r=0.80; P < 0.01). Chlorophyll content per unit phytoplankton biomass ranged over two orders of magnitude. Nitrogen seemed to be a major factor influencing the chlorophyll content of Florida algae. Multiple regression analyses indicated that phytoplankton biomass was dependent on both the total phosphorus and total nitrogen concentration. Nutrient-phytoplankton and Secchi-phytoplankton relationships for the Florida lakes had higher coefficients of determination if chlorophyll a concentrations rather than phytoplankton biomass data were used in regression analyses.     

大气扩散参数的取样时间订正

就大气环境影响评价浓度预测中 ,对大气扩散参数取样时间订正问题进行了说明和讨论。     

热水介质＋脱附破乳组剂处理高凝固点油泥的条件研究

通过热水介质添加脱附破乳组剂的方法,研究了辽河油田公司沈阳采油厂油泥分离的相关条件。通过油泥的组分分析、热水介质温度实验、处理时间实验、脱附破乳组剂浓度实验,确定了热水介质添加脱附破乳组剂实现油泥分离的条件:脱附破乳组剂浓度为15.0 g/L、洗涤温度50℃、洗涤时间大于5 min。     

大庆地区空气中总烃与非甲烷烃分布规律研究

分析了大庆地区空气中总径与非甲烷烃的比例关系，年、季、日变化规律及浓度水平。说明了总径与非甲烷径浓度水平在采暖期和非采暖期无显著差别，且冬、夏分布大体一致，高浓度多集中于大庆市东北部，浓度值向西南偏南方向递减，总烃总体浓度冬季较夏季偏向于西南这一规律。讨论了气候条件对分布规律的影响，并指出总烂的主要来源是油田开发和机动车尾气排放。     

金沙江流域水土流失与人类活动影响分析

长江三峡水利枢纽工程能否正常发挥效益，泥沙是重要的制约因素之一，而水库的泥沙主要来自上游金沙江，其多年平均输沙量占入库寸滩站的５２７％。因此，本文对金沙江泥沙的地区组成、水土流失及人类活动影响等问题进行了深入的分析，并提出了防治对策。     

NUTRIENT MASS BALANCE FOR THE ALBEMARLE-PAMLICO DRAINAGE BASIN,NORTH CAROLINA AND VIRGINIA, 19901

ABSTRACT: A 1990 nitrogen and phosphorus mass balance calculated for eight National Stream Quality Accounting Network (NASQAN) basins in the Albemarle-Pamlico Drainage Basin indicated the importance of agricultural nonpoint sources of nitrogen and phosphorus and watershed nitrogen retention and processing capabilities. Basin total nitrogen and phosphorus input estimates were calculated for atmospheric deposition (which averaged 27 percent of total nitrogen inputs and 22 percent of total phosphorus inputs); crop fertilizer (27 and 25 percent); animal-waste (22 and 50 percent, respectively); point sources (3 percent each of total nitrogen and total phosphorus inputs); and biological nitrogen fixation (21 percent of total nitrogen inputs). Highest in-stream nitrogen and phosphorus loads were measured in predominantly agricultural drainage areas. Intermediate loads were observed in mixed agricultural/urban drainage areas; the lowest loads were measured in mixed agricultural/forested drainage areas. The difference between the sum of the nutrient input categories and the sum of the in-stream nutrient loads and crop-harvest nutrient removal was assigned to a residual category for the basin. The residual category averaged 51 percent of total nitrogen inputs and 54 percent of total phosphorus inputs.     

PRA浓度和显色温度对West—Gaeke法测定SO2的回归斜率和空白值的影响

试验研究表明，Ｗｅｓｔ－Ｇａｅｋｅ法制定大气ＳＯ２，空白试验值不仅随显色温度增高而增高，而且随ＰＲＡ浓度增高而增高。尤其，在２０±２℃时，ＰＲＡ浓度＞０．０１６％时，校准曲线斜率比方法规定值偏高；称取ＰＲＡ０．１００ｇ提纯后使用，在３０℃时，回归斜率比方法规定值偏低。本文提出了对方法的补充意见。     

荠菜叶挥发性成分分析

采用水蒸气蒸馏法对荠菜叶挥发油进行了提取。通过毛细管气相色谱—质谱联用法分离并鉴定了其化学成分,用气相色谱面积归一化法测定了各成分的相对百分含量,共分离确定了其中12种化合物,所鉴定化合物的含量占全油的65.62%,主要化学成分为：L-胍基琥珀酰亚胺（21.28%）、植醇（18%）、植酮（9.6%）、油酸（4.71%）、棕榈酸（3.97%）等。     

微波消解-ICP—MS测定土壤和水系沉积物中的重金属

建立了一种采用逆王水和氢氟酸的混合体系微波酸消解土壤与水系沉积物,电感耦合等离子体质谱法快速测定六种金属元素（As、Cd、Pb、Cu、Cr和Ni）含量的方法。本文研究了消解温度和消解时间对消解效果的影响。结果表明,在190℃下运行25分钟对土壤与水系沉积物中的六种金属元素均具有很好的消解能力,备元素的测定值与标准值相符。在对实际土壤与水系沉积物样品进行分析后得出采样区域的土壤与沉积物中这六种金属含量水平正常。