长江口浮游植物群落的聚类分析

根据2003年8月长江口深水航道水生态调查20个站点所采集的浮游植物样品，对长江口丰水期浮游植物种类组成及群落结构进行了聚类分析。调查区浮游植物种类共检出50种，主要分属3种生态类型。聚类分析将20个站点聚合为3类（类群Ⅰ、Ⅱ、Ⅲ），类群Ⅰ主要位于长兴岛以西水域，为淡水性群落类型；类群Ⅱ和Ⅲ则位于长兴岛以东水域，分别为河口近岸低盐性群落类型和外海高盐性群落类型。上述3个类群中，以河口近岸低盐性群落类型种类最多。结合三个类群的环境指标来看，盐度、悬浮物浓度、浊度在三个类群中差异很大。     

长江下游甘蓝型油菜小孢子的培养体系

自从德国学者首次报道甘蓝型油菜小孢子培养技术成功以来[1],该项技术已被迅速采用.小孢子培养能够得到基因型纯合的甘蓝型油菜株系(双单倍体,Double haploid),利用该技术可以迅速纯合保持系和恢复系[2],避免性状分离;也可以对远缘杂交后代通过加倍来稳定外缘染色体[3];还可以结合诱变技术进行油菜种质资源创新,目前已经获得品质和抗性性状非常优良的株系[4,5].     

长江下游地区优质油菜高产稳产机制初探

研究了长江下游地区优质油菜新品种的丰产性和稳产性，并对其高产稳产机制进行了探讨。结果表明，产量构成三因素对产量的贡献大小顺序为，单株有效角果数＞每角粒数＞千粒重。产量的稳定性取决于产量构成因素的稳定性及相互作用。其中产量的稳定性与单株有效角果数的稳定性相关最密切，其次是千粒重的稳定性，每角粒数的稳定性对产量的稳定性影响最小。高产稳产品种一般单株有效角果数较多，且单株有效角果数和千粒重的稳定性较好。     

长江中下游平原湖区汛期稻田水管理

从长江中下游平原湖区农业生产与防洪除涝相结合的角度，就保持必要的稻田种植面积和江河汛期稻田水管理进行了探讨，提出利用水稻不同时期的耐涝性，科学地调控稻田蓄水深度，以减轻提排压力和防洪压力，促进本区社会经济持续发展。     

长江中游栓皮栎林水文生态效益研究

1998～ 1999年实测了河南境内长江中游栓皮栎林的林外降水、林内降水、树干径流以及下层植被和枯落物对降水的影响 ,并建立了相关的计算模型。结果表明 :观测期内栓皮栎林冠层能截留降水 2 0 .77% ,并将 4.85 %的降水转化为树干径流 ,枯落物的最大持水量为 13.40 t/ hm2 ,林外降水和林内降水、树干径流之间为线性关系 ,而林冠截留符合灰色模型     

造林学与水土保持学专家侯庆春研究员

侯庆春先生，研究员。1943年出生于吉林省吉林市，1965年毕业于东北林学院林学系，同年分配到中国科学院水利部水土保持研究所工作至今。30多年来一直在黄土高原从事森林生态学和造林学方面的研究工作，研究领域涉及到黄土高原造林的诸多领域，先后对黄土高原林草地土壤水分特征及区域分布、飞机播种造林种草技术，抗旱防风集流造林技术，区域林业、小流域综合治理，低产林改造等方面进行了深入系统的研究。     

Environmental change and its impacts on human settlement in the Yangtze Delta, P.R. China

Archaeological excavations and environment–archaeology studies over many years in the Yangtze Delta region have provided exceptional information about climatic variations, growth and demise of human civilization and human–environment interactions. The archaeological excavations show that the cultural layers of the Neolithic sites are interrupted by barren layers without any cultural relics (so-called cultural interruptions), which may be the result of harsh environmental conditions (arid, flooding, extreme cold or warmth). Temporal and spatial analyses of ¹⁴C-dates for buried trees, peat, shell ridges, and Neolithic sites show that environmental changes are responsible for the rise and fall of human civilization. The progress of human civilization was interrupted at least 5 times in the Yangtze Delta, matching 5 periods of high sea level, peat accumulation, and burial of trees. The collapse of the Liangzhu culture about 4000 BP was followed by the less-developed Maqiao culture and resulted from extreme environmental and hydrological conditions such as floods.     

Surface water quality of factory-based and vegetable-based peri-urban areas in the Yangtze River Delta region,China

Detailed surveys of surface water in two contrasting peri-urban areas in the Yangtze River Delta region of China were conducted to determine the distribution of heavy metals, nitrogen (N) and phosphorus (P) as well as the speciation of N and P. A factory-based (FB) area was compared with a vegetable-based (VB) area during the dry season. The concentrations of heavy metals in the surface water in the FB area were higher than those in the VB area, suggesting modest contamination of surface water with Zn, Cu, Cr and Pb but not Cd, from discharge of factory effluent in the FB area but not the VB area. Although total N (TN) and total P (TP) levels in the surface water were high in both areas, the surface water in the VB area had significantly higher levels of nitrate N (NO₃–N), organic N (ON) and TN than those in the FB area. In both areas, the levels of water-soluble P (WP), organic P (OP) and TP were high in the river water that received municipal wastewater. The distribution of N and P species throughout the surface water system indicated that the NO₃–N and ON mainly came from vegetable fields, while ammonium N (NH₄–N), WP and OP were mainly from municipal wastewater. Treatment of municipal wastewater prior to discharge to reduce N and P by purification is recommended together with research and extension to develop more efficient use of N and P fertilizer by vegetable farmers.     

长江三角洲典型地区土壤性质对土地利用变化的响应—以江苏省锡山市为例

以锡山市为分析样区,对土壤pH、有机质、全氮、全磷、速效氮、速效磷和速效钾等7个指标对旱地变为未利用地、水田变为菜地、水田变为旱地、水田变为林地和水田变为未利用地等五种变化方式的响应进行了研究.结果表明,土地利用变化对土壤性质有显著影响,但不同变化方式对各指标的影响方向及影响程度不同：（1）水田变为菜地、旱地和林地使土壤向酸化方向发展,土壤pH分别降低0.47、0.78和0.17;旱地和水田变为未利用地分别使土壤pH提高0.24和0.74;（2）水田变为未利用地、菜地和林地分别使有机质降低3.83、3.18和0.35 g kg^-1;水田变为旱地、旱地变为未利用地分别使有机质含量增加7.58和1.07 g kg^-1;（3）旱地变为未利用地、水田变为菜地和未利用地分别使全氮降低0.31、0.08和0.11 g kg^-1;水田变为旱地和林地分别使全氮提高0.41和0.04 g kg^-1;（4）旱地变为未利用地使全磷有微小幅度的降低,降低量为0.01 g kg^-1;水田变为菜地、旱地、林地和未利用地后不同程度地提高全磷含量,增加量分别为0.23、0.08、0.23和0.09 g kg-1;（5）旱地和水田变为未利用地分别使速效氮降低2.38和7.62 mg kg^-1;水田变为菜地、旱地和林地分别使速效氮增加11.61、34.51和18.26 mg kg^-1;（6）旱地变为未利用地使速效磷降低3.70 mg kg^-1;水田变为菜地、旱地、林地和未利用地分别使速效磷增加45.16、7.54、40.55和10.94 mg kg^-1 ;（7）旱地变为未利用地以及水田变为菜地、旱地、林地和未利用地均使速效钾含量有所增加,增加量分别为8.75、77.44、32.28、160.4和27.59 mg kg^-1.     

长江流域及其西南诸河城市水土保持的经验与成效

1997年以来 ,长江流域及其西南诸河的城市水土保持发展很快 ,取得了有益的经验 :制定科学规划 ,明确防治目标 ;加强领导 ,搞好部门配合 ;广泛宣传 ,增强全民水土保持意识 ;配套法规 ,依法行政 ;加强监督 ,严格执法 ;多方投入 ,建设秀美家园。同时 ,城市水土流失得到有效控制 ;城市生态环境大为改善 ,市民生活质量不断提高 ;城市基础设施得到有效保护 ;城市投资环境改善 ,为经济发展创造了条件。新世纪长江流域的城市水土保持将抓好示范带动 ,认真总结提高 ,以依法编报审批开发建设项目的水土保持方案为城市水土保持工作的核心 ,全面推进城市水土保持的发展