干旱胁迫下山栏稻与栽培水稻品种苗期表型性状及生理差异

测定了在干旱胁迫条件下,山栏稻苗期的株高、叶面积等农艺性状以及叶片脯氨酸含量、MDA含量等生理指标,采用隶属函数法评估山栏稻抗旱能力。结果表明,在干旱胁迫下,山栏稻降低了地上部分的生物量并增加了地下部分的生物量,同时,山栏稻叶绿素含量、MDA含量以及脯氨酸含量均有不同程度的提高;所选山栏稻品种的隶属函数值为0.521和0.673。综合实验数据和田间观察,初步判断山栏稻苗期具有较强的抗旱特性。     

二氧化碳麻醉技术在罗非鱼无水保活运输中的应用研究

采用二氧化碳(CO2)对罗非鱼进行麻醉,以麻醉时间、复苏时间为指标,探讨CO2浓度、水温、浸浴时间对罗非鱼麻醉效果的影响.结果显示,水温25℃、浓度0.41～ 1.13 mg/L时,随着浓度的增加,麻醉时间缩短,复苏时间延长;浓度0.58 mg/L时,水温由10℃升高到30℃时,麻醉时间呈先上升后下降的趋势,复苏时间呈下降趋势.罗非鱼血浆生化指标分析表明,麻醉中罗非鱼的乳酸脱氢酶、谷草转氨酶、谷丙转氨酶活性分别与麻醉前、麻醉后差异显著(P＜0.05);麻醉中罗非鱼的肌酐、尿素氮、乳酸含量显著高于麻醉前和复苏后;与麻醉中罗非鱼的血浆生化指标相比,复苏后的罗非鱼血浆生化指标均下降.研究表明,CO2对罗非鱼有麻醉作用,CO2麻醉可辅助罗非鱼无水保活运输.     

居住区绿化研究

介绍了居住区绿化的设计原则,分析了目前居住区绿化设计中存在的主要问题与对策,并详细阐述了居住区绿化中植物的配置方法。     

结合遥感数据对云贵地区蒸散发量及干湿变化特征的研究

利用卫星遥感观测MOD16和全球陆面数据同化系统(GLDAS)的逐月实际蒸散量(MOD16_ETa及GLDAS_ETa)与潜在蒸散发(MOD16_ETp及PM_ETp),探讨了2000-2014年云贵地区蒸散发时空变化规律,并综合利用蒸散发数据与降水数据计算多种干湿指数,分析了云贵地区近15年的干湿变化状况以及蒸散发、...     

EXTERNALITIES,INSTITUTIONS AND THE LOCATION CHOICES OF SHELLFISH PRODUCERS: THE CASE OF BLUE MUSSEL FARMING IN THE MONT-SAINT-MICHEL BAY (FRANCE)

ABSTRACT

Most marine aquaculture activities remain strongly dependent on coastal ecosystems. In the case of shellfish farming, this dependency is related mainly to water quality and to the various ecological interactions resulting from the dynamics of coastal food webs. Such ecological constraints have influenced the overall evolution of blue mussel farming in the Mont-Saint-Michel Bay, leading producers to negotiate collective arrangements regarding production capacity and techniques and to develop production strategies at the farm level. This article presents an analysis of the location choices of mussel farmers in the Mont-Saint-Michel Bay based on an empirical investigation conducted in 2002. A typology of farms with respect to their land structure is developed in which some farms choose to concentrate their activity in a single part of the bay while others distribute their activity more widely. Determinants of the location choices of each farm category, including distance to port, natural productivity differentials, and predation of mussel stocks, are analyzed. The role of the institutional arrangements allowing mussel farmers to develop these location strategies is also discussed.     

Tissue indicators of element status in Atlantic salmon (Salmo salar) post-smolts: effect of fasting

Two groups of Atlantic salmon post-smolts previously fed diets either unsupplemented or supplemented with Zn, Fe, Cu and Mn were fasted for 6 weeks in order to study the reliability of tissue indicators of element status during fasting. The fish were weighed at 2-week intervals and samples of whole fish liver, vertebrae, serum and eyes were taken for analyses of elements by atomic absorption spectrometry.
Body weight, per cent dry matter, condition factor and haematocrit values decreased during the fasting period. The concentration of elements in whole body remained constant, indicating that whole body is a stable indicator of element status during fasting. Other tissues seemed to be more sensitive (i.e. hepatic Fe concentration and vertebrae Zn and Mn concentrations). The serum concentrations of the elements generally decreased during fasting, especially for P and Zn. Element concentrations in whole body and most tissues during fasting were generally more dependent upon initial element status than on the fasting itself.
Care should be taken in drawing conclusions about the element status of fish based solely upon the examination of serum concentrations, and more than one tissue indicator should be used in the establishment of the element status of fish.     

后金融危机时代中小企业财务危机预警管理

2008年的全球性金融危机给我国中小企业带来了巨大的冲击，绝大多数中小企业陷入了财务困境，甚至破产倒闭。在后金融危机时代，我们应该吸取经验教训，提高中小企业财务危机意识，加强财务危机的预警，防患于未然，因此建立中小企业财务危机预警模型成为刻不容缓的任务之一。文章尝试在传统的基于功效系数法下构建的中小企业财务危机预警模型中加入了关键性的非财务指标，试图通过定量与定性指标的结合，以期增加模型的全面性与准确性。     

Spoilage of Lightly Salted Lumpfish (Cyclopterus lumpus) Roe at 5 ° C

Abstract

Lightly salted lumpfish roe (3.5–4.8% fw/w] salt in the water-phase, pH 5.4, vacuum-packed) was stored at 5°C. After 2 1/2 or 3 months of storage, different degrees of spoilage, caused by bacterial activity, occurred in eleven roe batches. Off-odors ranged from no or very weak odors to strong sulphury, sour odors. The microflora consisted of lactic acid bacteria, Enterobacteriaceae and Vibrio spp. Concentration of lactic acid, acetic acid, trimethylamine and total volatile bases were unrelated to spoilage odors. Volatile sulfur compounds (H₂S, probably CS₂, CH₃SH and CH₃CH₂SH or CH3SCH3), produced during storage, appeared to be contributors to spoilage odors.     

Frequency of symptomatic trees removal in small citrus blocks on citrus huanglongbing epidemics

Among the recommended measures for citrus Huanglongbing (HLB) management, the systematic elimination of symptomatic trees is the most argued and difficult to be accepted and accomplished by citrus growers. Elimination of recently affected HLB trees represents a short term yield loss and cost increase due to the need of frequent inspections and removal operations. This work aimed to evaluate the effect of different frequencies of inoculum reduction applied at individual citrus blocks scale (or local inoculum reduction) on HLB temporal progress. Eight experiments were carried out in new planted and older citrus blocks with 504–1290 trees/plot. In all experiments, inspections to detect symptomatic trees were done in a fortnightly or monthly frequency. The treatments of frequencies of local inoculum reduction varied from fortnightly to 6 months. Annual disease progress rate was estimated by logistic model for each plot. No difference on HLB progress rates among treatments was observed, except in experiments 1 and 3 where less frequent tree removal resulted in higher disease progress rate. This ineffectiveness of local inoculum reduction on the disease progress rate was explained by the higher weight of primary spread on HLB epidemics than the secondary spread within plots associated with small size and narrow shape of treated plots (except for experiments 1 and 3), high dispersal capacity of HLB-insect vector among plots and groves, and strong control of psyllid within the plots (except for experiment 1, with poor insecticide spray program). Also, the high amount of inspections to detect symptomatic trees before the eradication treatment, which reduced the escapes (asymptomatic and non visual detectable diseased trees) contributed for these results. It is important to note that these results were obtained with only small citrus plots (0.8–2.9 ha) and they cannot be extended to larger groves and farms amenable to HLB management by the symptomatic tree removal and vector control.