南四湖地区甜瓜病虫害防治中的农业面源污染防控研究

通过生物农药绿色替代和农药减量与精准施用技术应用,研究其在甜瓜白粉病、霜霉病、炭疽病等真菌病害防治中的病虫防治效果、经济效益、环境效益,为地区农业病虫防治中农药替代、减施增效,防止或减缓农业面源污染提供依据.     

利用地衣监测大气污染研究进展

介绍了大气清洁度指数法、地衣微核检测法等地衣监测大气污染的几种常用方法,并针对地衣对各种污染物的监测研究进行讨论.在总结国内外相关研究的基础上,探讨了目前我国地衣研究中存在的问题和未来研究方向.     

一株异养脱氮菌的分离及脱氮性能研究

经过野外采样、稀释平板法、富集培养等步骤进行初步筛选得到12株菌,并通过测定其对NH4+-N去除效果,复筛得到1株对NH4+-N去除率最高的菌株,命名为Y8。该菌株为革兰氏阴性杆状菌。通过小试的初步研究,考察了不同碳源、温度、pH值、摇床转速对Y8去除NH4+-N的影响,实验结果表明:Y8在以丁二酸纳为唯一碳源、温度30℃、pH值9.5、转速150 r/min条件下去除NH4+-N效果最好;并且在有氧情况下对NO3--N和NO2--N均有一定去除效果。     

Where clocks are redundant: weak circadian mechanisms in reindeer living under polar photic conditions

Biological rhythms are a result of interplay between endogenous clocks and the ambient light–dark (LD) cycle. Biological timing in resident polar organisms presents a conundrum because these experience distinct daily LD cycles for only a few weeks each year. We measured locomotor activity in reindeer, Rangifer tarandus platyrhynchus (SR, n = 5 and 6) and R. tarandus tarandus (NR, n = 6), ranging freely at 78 and 70°N, respectively, continuously throughout 1 year using data loggers. NR, but not SR, are gregarious which enabled us to examine the integrated effects of differences in social organisation and the photic environment at two different latitudes on the organisation of activity. In both sub-species, ultradian bouts of activity and inactivity alternated across the 24-h day throughout the year. This pattern was modified by the LD cycle in NR but barely at all in SR. Periodogram analysis revealed significant ultradian rhythmicity in both sub-species; the frequency of daily cycles of activity increased from three per day in winter to nearly five in summer. We conclude that this increase, and a concomitant increase in the level of daily activity, reflected the seasonal increase in the animals’ appetite and the quality of their forage. Secondly, the combination, most evident in SR, of a weak photic response, weak circadian mechanisms and a weak social synchronization reduces the constraints of biological timing in an environment which is effectively non-rhythmic most of the year and permits expression of the basic ultradian pattern of ruminant activity. Third, the weaker 24-h rhythmicity in SR compared to NR indicates a latitudinal decrease in circadian organization and photic responsiveness in Rangifer.     

复合生物法处理炼化污水厂恶臭气体

介绍了“生物洗涤+生物滴滤”的复合生物法在某炼化企业污水处理厂治理恶臭污染的工艺原理、技术流程、过程控制和实践效果,分析讨论生物处理装置运行影响因素。实践结果表明,复合生物技术对炼化企业污水处理厂恶臭治理具有较为理想的恶臭净化效果,其中硫化氢处理效率可达到98%,非甲烷总烃处理效率可达到94%,且运行操作简便、成本低廉、无二次污染。     

Effects of water regime, crop residues, and application rates on control of Fusarium oxysporum f. sp. cubense

Biological soil disinfestation is an effective method to control soil-borne disease by flooding and incorporating with organic amendments, but field conditions and resources sometimes limited its practical application. A laboratory experiment was conducted to develop practice guidelines on controlling Fusarium wilt, a widespread banana disease caused by Fusarium oxysporum f. sp. cubense(FOC). FOC infested soil incorporated with rice or maize straw at rates of 1.5 tons/ha and 3.0 tons/ha was incubated under flooded or water-saturated(100% water holding capacity) conditions at 30℃ for 30 days. Results showed that FOC populations in the soils incorporated with either rice or maize straw rapidly reduced more than 90% in the first 15 days and then fluctuated till the end of incubation, while flooding alone without organic amendment reduced FOC populations slightly. The rapid and dramatic decrease of redox potential(down to- 350 m V) in straw-amended treatments implied that both anaerobic condition and strongly reductive soil condition would contribute to pathogen inactivation. Water-saturation combined with straw amendments had the comparable effects on reduction of FOC, indicating that flooding was not indispensable for inactivating FOC. There was no significant difference in the reduction of FOC observed in the straw amendments at between 1.5 and 3 tons/ha. Therefore,incorporating soil with straw(rice or maize straw) at a rate of 3.0 tons/ha under 100%water holding capacity or 1.5 tons/ha under flooding, would effectively alleviate banana Fusarium wilt caused by FOC after 15-day treating under 30℃.     

The effect of landscape type and landscape elements on public visual preferences: ways to use knowledge in the context of landscape planning

This study deals with an assessment of the visual quality of landscapes, and specifically with the perception of selected elements in the landscape. The aim of the study was to find out how particular elements are perceived in various landscape types, whether this perception is affected by the landscape type in which the elements are placed, and to what extent the respondents’ characteristics affect the assessment. The study was carried out with a sample of respondents of various ages, educational levels and types of employment. The respondents came from Slovakia and the Czech Republic. The preferences of the respondents were determined using an online questionnaire, in which they rated landscape photographs on a 21 point rating scale with a range from ?10 to +10 points. Using generalised linear mixed effect models, it was found that the perception of an element is most affected by the landscape type, since the same element was assessed differently according to the landscape in which it was situated. The results confirmed that selected elements which do not disturb the harmony of the landscape are generally positively perceived, and the selected elements of a technical character are generally negatively perceived. Among the characteristics of the respondents, only gender and the respondent's current place of residence have an effect on their visual preferences.     

海河流域14条河流表层沉积物中多溴联苯醚的分布特征

海河流域是我国受人类活动扰动强度最大的地区,为了解多溴联苯醚（PBDEs）在该流域的污染现状与分布特征,通过采集14条主要河流的48个表层沉积物样品,采用高分辨的GC-MS/MS技术对干燥后的沉积物中27种PBDEs进行分析.结果发现沉积物中PBDEs的平均含量范围为0.06～2.10 ng·g^-1;其中徒骇河沉积物...     

中国荸荠属植物果皮微形态特征及其分类学上的意义

报道了国产荸荠属２６ 种、３ 变种植物果皮在扫描电镜下的纹饰特征．结果表明,根据果皮细胞形状和外壁纹饰的差异,可分：（１） 光滑型纹饰：果实表面光滑,无细胞结构;（２） 网状纹饰：在（２） 类型中根据植物果皮垂周壁的结构和细胞形态又可分为两个亚型,即网状纹饰亚型和波形网状纹饰亚型．本属植物果皮微形态特征总体而言较为相近,表明是一个自然类群．果皮纹饰类型及微形态特征在组间或系间相互交叉和渗透,与传统分类中组、系的划分不相对应．此外,本属果皮微形态特征在种下等级的差异较明显,但在种内个体间比较稳定,变异很小．上述研究结果可为国产荸荠属种间区别提供依据．     

美国大气污染物排放标准体系综述

介绍了美国大气固定源排放标准的体系、标准内容、标准制定程序与标准实施的有关规定。并分析了其特点。