繁茂膜海绵滤食养殖水体中过剩饵料的研究

繁茂膜海绵(Hymeniacidon perleve)可滤食养殖水体中的残饵。对活体饵料新月菱形藻(Natzchia closterum),在无营养盐条件,5 g鲜重海绵处理300 mL,藻数量为1.62×106/mL的藻液240 h后,处理组藻的平均浓度仅为对照组的2.9%,为初始浓度的17.2%;在有营养盐条件,5g鲜重海绵处理300 mL,藻数量为0.87×106mL-1的藻液220 h后,对照组的藻仍处于指数生长期,此时处理组藻的平均浓度仅为对照组的0.05%,为初始浓度的64.4%。对死体海参饵料—藻粉和鱼粉蛋白等,由于海绵的滤食作用,海水中颗粒物的浓度随时间增加而呈指数曲线降低。1.5 g鲜重海绵处理200 mL,含200 mg/L海参饵料的海水,在第4d时,海绵已滤食72.6%的颗粒物,有机颗粒物的最大比截留速率为21.6×10-3/d.L。同时,海绵的生物量明显增加。     

Bioconcentration and half-life of quinalphos pesticide in rice-fish integration system in the Mekong Delta,Vietnam

In order to determine the distribution and enable the elimination of quinalphos, a popular active pesticide compound used in the Mekong Delta, an experiment was set up in a rice-fish integration system in Can Tho City, Vietnam. Fish was stocked into the field when the rice was two-months old. Quinalphos was applied twice in doses of 42.5 g per 1000 m². Water, fish and sediment samples were collected at time intervals and analyzed by a Gas Chromatography Electron Capture Detector system. The results show that quinalphos residues in fish muscles were much higher than those of the water and the bioconcentration factor (logBCF) was above 2 for the fish. The half-life of first and second quinalphos applications were 12.2 and 11.1 days for sediment, 2.5 and 1.1 days for silver barb, 1.9 and 1.3 days for common carp, and 1.1 and 1.0 days for water, respectively.     

可用于水体污染控制的氨氮转化菌筛选及部分降解特性的实验研究

从南京禄口水产养殖基地淡水鱼塘取淤泥作为分离菌株的土源,采用选择性富集培养法,从中分离到能以硫酸铵为氮源的菌株7株,对7个菌株进行氨氮降解实验,它们氨氮转化率分别为14.8%、19.7%、53.4%、94.2%、29.1%、63.5%和41.7%,其中AN-4菌株的转化率最高且生长良好。通过AN-4菌株16S rRNA基因序列分析以及生理生化方法,鉴定此菌株为克雷伯氏菌属(Klebsiellasp.)。对菌株AN-4转化氨氮的特性及温度、pH值、氨氮初始浓度和菌株接种量对其氨氮转化率的影响研究,结果表明,菌株AN-4降解氨氮的最适条件为:温度为30℃和pH值为8.0;当氨氮初始浓度为30mg/L时,AN-4菌株在24 h内的氨氮降解率可达85%以上,且能耐受高达200 mg/L的氨氮浓度;AN-4活化菌液浓度为108cfu/mL,当接种量为3×106cfu/mL时,AN-4菌株在24 h内的氨氮降解率为87.75%。综合上述结果,符合淡水养殖水环境条件,说明AN-4菌株适合在水产养殖中应用,为将菌株AN-4应用于水产养殖环境修复提供了理论依据。     

不同密度螺-草结构对养殖尾水净化效果的比较研究

为减少水产养殖污染物排放,以苦草为对照组,构建环棱螺螺 草生态系统净化池塘养殖尾水,比较不同密度螺 草结构对养殖尾水的净化效果,同时探讨螺草互作对水质的影响。结果表明不同密度螺 草组合对养殖尾水均有较好的净化效果,以中密度组（螺密度50 ind/m3）的去除效果最优,25 d对Chl a、CODMn、TN、TP、NH4+ N、NO3- N和浊度的去除率分别达到98%、39.7%、44.2%、86.9%、58.2%、82.3%和91%,其中以17~25 d的营养物质去除率最高,水质由原来的Ⅳ类、Ⅴ类水提升为Ⅲ类水;环棱螺 苦草互作对水体的净化效果与苦草对照组差异不显著,表明其互利关系不明显;环棱螺 苦草组合对CODMn和TN的去除效果不是很理想,可能是由于实验中以黄土为底泥,其中的异养微生物较少引起的     

Abundance and removal of antibiotic resistance genes (ARGs) in the rearing environments of intensive shrimp aquaculture in South China

Although research regarding antibiotic resistance genes (ARGs) in aquaculture environments has gained increasing scientific interest, further studies are required to understand the abundances and removal mechanisms of ARGs during the entire rearing period of shrimp aquaculture. Thus, in this study, abundances, distributions and removal rates of ARGs in different environmental compartments of intensive shrimp farms in South China were investigated during the entire rearing period. The results indicated that sul1 and cmlA were the predominant ARGs in the water and sediment samples. Additionally, the total abundance of ARGs was higher in shrimp pond water than in the source water and farm effluent. Moreover, sediment samples indicated significantly higher ARG abundances than water samples from the shrimp ponds (P?<?0.05). Environmental factors were found to significantly affect the distribution of ARGs in shrimp rearing environments. Furthermore, stable ponds aided the removal of ARGs from shrimp pond water. This study accounted for temporal variations in ARG abundances as well as removal of ARGs in different environmental compartments during the entire shrimp rearing period. However, additional research is required to optimize the water treatment process for removal of ARGs from the aquaculture.     

两种AHLs信号分子对生物膜法养殖污水处理条件下水体内环境的影响

为提高生物膜法处理养殖污水的效果,对不同信号分子条件下的生物膜处理情况进行研究。在室内循环水养殖系统中,设定3个实验组和1个对照组,分别添加乙醇、C6-HSL、N-3-oxo-C8-HSL和蒸馏水,并在模拟过程中取样分析。实验结果表明,3个实验组附着基上的生物量明显多于对照组,尤其是添加N-3-oxo-C8-HSL组产生的生物量约为对照组的6倍;经添加C6-HSL和N-3-oxo-C8-HSL处理的养殖水体中,亚硝酸盐最终浓度比对照组低28.6%,但无机磷浓度稍高。数据因子分析结果表明,实验过程中(9～27 d),添加AHLs信号因子C6-HSL和N-3-oxo-C8-HSL两组养殖水体内环境的总体得分较高,说明养殖水体的内环境处于较好状态。     

纳米生态基对水产养殖污水的处理效果

采用三因子四水平的正交设计,实验研究了纳米生态基在不同温度、溶解氧和水力停留时间下对水产养殖污水的处理效果,确定了纳米生态基处理养殖污水的最佳条件。结果表明,含氨氮和亚硝氮浓度较高的模拟养殖污水用纳米生态基挂膜,所需时间约为22 d。纳米生态基对氨氮的去除效果明显,平均去除率达到93.5%。对氨氮去除率的影响程度,水力停留时间>温度>溶解氧。当温度为30℃,DO为5.43 mg/L,HRT为0.33 h时,纳米生态基对氨氮的处理能力最佳,去除率达到94.6%。纳米生态基对亚硝氮的平均去除率为69.3%。对亚硝氮去除率的影响程度,水力停留时间>溶解氧>温度。当温度为21℃,DO为6.40 mg/L,HRT为0.33 h时,纳米生态基对亚硝氮的处理能力最佳,去除率为71.5%。纳米生态基处理养殖污水的最佳条件:温度为30℃,DO为6.40 mg/L,HRT为0.33 h。     

Linking Salmon Aquaculture Synergies and Trade-Offs on Ecosystem Services to Human Wellbeing Constituents

Salmon aquaculture has emerged as a successful economic industry generating high economic revenues to invest in the development of Chiloe region, Southern Chile. However, salmon aquaculture also consumes a substantial amount of ecosystem services, and the direct and indirect impacts on human wellbeing are still unknown and unexplored. This paper identifies the synergies and trade-offs caused by the salmon industry on a range of ecosystem services. The results show that large economic benefits due to the increase of provisioning ecosystem services are also causing a reduction on regulating and cultural services. Despite the improvement on average income and poverty levels experienced in communities closely associated with the sector, this progress is not large enough and social welfare did not improve substantially over the last decade. The rest of human wellbeing constituents in Chiloe region have not changed significantly compared to the development in the rest of the country.     

水产养殖与有毒有害污染物残留及其环境影响

文章介绍传统养殖模式虽然有着良好的环境效益,但养殖产量比较低下,不能满足市场需求;现有水产养殖模式养殖结构简单,过度依赖化学农用品的调控,饲料添加剂、生长促进剂、杀虫剂、抗生素等各种化学品的频繁而广泛使用,极大地阻碍了水产养殖业的可持续发展,要降低水产养殖对环境的负面影响,减少水产品中有毒有害物质的污染,必须调整现有的养殖模式,吸收传统水产养殖业中多元化、多层次特点和现代养殖模式中的集约化、规模化特点,摈弃高消耗、高污染的发展模式,合理使用农用化学品,控制养殖水体的污染,发展绿色水产品生产,走可持续发展的道路,这是未来水产养殖业发展的必然方向。     

深圳农业面源污染与近岸水体富营养化关系研究 III.水产养殖排污分析

对1991年至2000年间深圳内陆和近岸水产养殖业的排污量进行估算,分析其演变趋势,并对同时期深圳市的点源污染和农业面源污染进行了比较,结果表明:(1)深圳市水产养殖业排污也是深圳近海水体富营养化主要成因之一,自1994年之后其对近海水体污染有加重趋势;(2)在农业面源中,畜禽养殖业排污量最大,其次是水产养殖,再次是农田化肥流失排污;(3)在点源污染中,城市生活污水已成为主要污染源,工业废水排污在点源污染中的比重有较大程度的降低;4)点源污染与面源污染相比,在排放COD量的比例上,前者是后者的两倍多,在排放TN量所占比例上,二者相近,在排放TP所占比例上,前者小于后者。