大型山地城市绿地景观动态及驱动力分析

利用1995年和2007年两期TM和ETM遥感影像数据,结合实地调查,研究了重庆市主城区20世纪90年代中期以来绿地景观格局时空变化特点与成因,讨论了不同绿地类型景观区域格局变化。结果表明,（1）重庆成直辖市以来,研究区整体上绿地景观多样性增加,优势度下降,破碎化增加,景观结构变化呈上升趋势。（2）有林地和其他林地比重减轻,景观破碎度增加;高覆盖度草地面积增加明显,破碎化轻微增加,低覆盖草地破碎化降低。（3）绿地景观斑块形状较规则,其中林地景观斑块形状更复杂,属研究区内优势植被类型。（4）研究区内绿地景观同非绿地景观类型间转化明显,表明其受到较强烈的干扰。其中在海拔200 m以下、坡度6＆#176;下城市绿地受到干扰最强烈。北碚区和沙坪坝区内绿地景观年变化速率最高。（5）自然灾害（火灾和酸雨）和人为经济、社会活动（包括植被经营和管理、旅游开发和其他人为干扰活动等）是研究时段内绿地景观格局变化主要驱动因素。     

Fungal inoculation induces agarwood in young Aquilaria malaccensis trees in the nursery

Fungi are often used to induce agarwood inAquilariatrees. This study was conducted to evaluate the effect of several fungi on agarwood formation over time in youngAquilaria malaccensis （Lam.） trees. Typical changes in the length and light intensity of the resulting discoloration were observed after three and six month periods following inoculation. Wood samples were observed microscopically and classified into several light intensity groups. The discoloration length was meas-ured longitudinally. The duration after inoculation affected the mean of discoloration length： the 6-month old sample （1.70 cm） had a wider discoloration zone when compared to the 3-month old sample （1.17 cm）. When measuring the discoloration intensity, a positive relationship with time was perceived. Digital images, captured using a camera-equipped microscope, revealed that wood samples collected after six months appeared to be 1.8-times darker than after three months. We concluded that time, not the species of any of the tested fungi, had significant effect on discoloration length and intensity. Gas chromatography/mass spec-trometry （GCMS） analysis of the 6-month old sample yielded some important agarwood compounds such as benzylacetone, anisylacetone, guaiene and palustrol. This demonstrates that the tested fungi have the ability to induce agarwood formation in nurseryA. malaccensis trees.     

浅谈牛栏江河道绿化的途径及措施

指出了当前牛栏江水污染严重,牛栏江生态廊道绿化的任务是提高河流“自净”能力,净化水质。探讨了绿化技术途径,包括对河岸带进行区划,确定各带（区）的功能,根据各带（区）特点,布置植物,强调在有限的空间内,千方百计地增加湿生与水生植物种植面积,利用水生植物净化水体,从而实现规划目标。     

考虑空气影响的干旱区土壤水分运移模式研究

在前人研究的基础上,根据石河子垦区的实际情况,确定模型特定的边界条件及参数,建立适合该区的包气带-饱和带水、气二相流的质热传输模型,模拟土壤水分、温度的动态变化,并利用实测土壤温度、土壤含水率数据进行模型检验。结果表明:模拟的土壤温度和含水率能够较好地反映实测值的变化规律,各土层模拟精度评价指标表明考虑空气影响的模拟结果更接近实测结果。对于9.7 mm日降水量的入渗深度,耦合模型可影响20 cm深土壤含水率,单相模型可影响到30 cm深左右。降水当日考虑空气模拟的蒸发速率比不考虑空气模拟的蒸发速率大7.7%;降水后1 d,不考虑空气影响导致蒸发速率比考虑空气的小3.19%。计算模拟期2种模型土壤总蒸发量,相差不大。根据2种模型水量平衡分析结果对比蒸发量的计算值与模拟值,发现考虑空气影响的模型模拟结果更可靠。     

尼罗罗非鱼六个性别相关标记的FISH分析

从尼罗罗非鱼（Oreochromis niloticus）BAC基因文库5个克隆中提取和纯化含有6个性别连锁或相关标记（CLC5，GM204，GM271，GM354，UNH995和UNH104）的重组质粒DNA作为模板，以简并核苷酸为引物，通过PCR制备原位杂交探针。探针用荧光素进行标记，并与尼罗罗非鱼中期相染色体进行荧光原位杂交以确定这些标记在尼罗罗非鱼染色体上的位置和分布。结果显示，这些性别连锁或相关标记都位于尼罗罗非鱼第一对染色体长臂近末端，从分子细胞学角度验证了第一对染色体是尼罗罗非鱼的性染色体。另外由于这些标记的荧光信号在XY个体的2条性染色体上都有，一方面说明这些标记在罗非鱼上还不是性别特异的；另一方面也验证了尼罗罗非鱼的性染色体还处于分化的早期阶段。【中国水产科学，2006，13（4）：525—529】     

我国远洋渔业的发展浅析

我国远洋渔业自新中国成立后有了长足发展，但是，仍然面临着严重的问题。尤其是《国际海洋法》生效后，我国远洋渔业的发展环境将更加严峻。因此，政府应该通过加大投资力度、开展渔业外交、寻找新的合作伙伴等措施来积极推动远洋渔业的发展。     

Identification of Mycobacterium spp. isolated from snakehead, Channa striata (Fowler), and Siamese fighting fish, Betta splendens (Regan), using polymerase chain reaction–reverse cross blot hybridization (PCR–RCBH)

A variety of methods have been used to identify Mycobacterium spp. isolated from snakehead and Siamese fighting fish, including biochemistry, mycolic acid profiles and antibody-based methods. However, these methods are unable to differentiate between different species of Mycobacterium . Polymerase chain reaction (PCR) followed by reverse cross blot hybridization (RCBH) was adapted in this study to speciate aquatic mycobacteria. The method was highly specific for Mycobacterium spp. and identified the bacteria to species level with a detection limit of 100 fg DNA, equivalent to 20 mycobacteria. Twenty-nine isolates previously collected and cultured from Siamese fighting fish (10 isolates) and snakehead (19 isolates) during outbreaks of mycobacteriosis were analysed using PCR–RCBH. Six of the Siamese fighting fish isolates and nine of the snakehead isolates were identified as Mycobacterium fortuitum , while the remainder were classified as M. marinum . Notably, two isolates recovered from snakehead and Siamese fighting fish, previously identified as M. poriferae and M. piscicida , respectively, were confirmed to be M. fortuitum .     

中国贝类染色体研究现状与进展

对我国已报道的81种贝类染色体研究进行了综述,并结合贝类分子系统进化研究成果,探讨了我国贝类染色体数目与染色体组成的进化趋势。     

广东海南两省海库潮间带生物量

广东海南两省海库潮间带生物量关则良，揭振英，周元建（湛江水产学院，５２４０２５）关键词潮间带，生物量，ＳＡＳ系统ＢＩＯＭＡＳＳＩＮＣＯＡＳＴＡＬ，ＴＩＤＡＬＺＯＮＥＯＦＧＵＡＮＧＤＯＮＧＡＮＤＨＡＩＮＡＮ￥ＧｕａｎＺｅｌｉａｎｇ；ＪｉｅＺｈｅｎｇｙｉ...