Evidence of reproductive disturbance in Astyanax lacustris (Teleostei: Characiformes) from the Doce River after the collapse of the Fundão Dam in Mariana,Brazil

Environmental Science and Pollution Research - The Fundão Dam collapsed, on November 5th, 2015, dumping more than 50 million/m3 of iron ore tailings, enriched with metals, into the Doce River...     

乡村振兴视域下农村土地利用利益相关者分析

乡村振兴的实施使得农村土地利用与管理面临更多的挑战。应用利益相关者分析、博弈均衡分析和实证案例分析,探讨乡村振兴视域下土地利用各利益相关者的关系演变。研究结果显示：（1）1949年至今,农村地区土地利用利益相关者主体数量增加,博弈关系呈现复杂化、多样化和多向化;（2）乡村振兴时期主要有六种博弈关系,并探讨了案例村实施下山脱贫、发展乡村旅游、新型经营主体进驻、城市居民促进农村发展四种博弈决策过程;（3）乡村振兴视域下,农村地区发展应关注基础设施配套、土地利用效率与生态环境协调、农户生计可持续性等问题。乡村振兴中应注重实现土地利用各利益相关者的最优均衡,降低各方风险,保护生态环境并寻求多方利益平衡。     

Speciation of arsenic using solid phase extraction cartridges

Various solid phase extraction (SPE) cartridges were investigated for speciation of arsenite [As(III)], arsenate [As(v)], monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Cartridges containing different types of sorbent materials were tested for arsenic retention and elution characteristics. Alumina cartridges were found to completely retain all the four target arsenic species, and are suitable for removal and preconcentration purposes. For speciation analysis, different arsenic species were separated on the basis of their selective retention on and elution from specific cartridges. DMA was retained on a resin-based strong cation exchange cartridge and eluted with 1.0 M HCl. MMA and As(v) were both retained on a silica-based strong anion exchange cartridge and sequentially eluted with 60 mM acetic acid (for MMA) and 1.0 M HCl [for As(v)]. As(III) was not retained on either cartridge and remained in solution. Arsenic species in solution and those eluted from the cartridges were subsequently quantified by using flow injection with hydride generation atomic fluorescence spectrometry (FI-HGAFS) and hydride generation atomic absorption spectrometry (FI-HGAAS). A detection limit of 0.05 microg L(-1) arsenic in water sample was achieved using HGAFS. An application of the method was demonstrated at a drinking water treatment facility. As(III) and As(v) species were determined in water at various stages of treatment. The method is suitable for routine determination of trace levels of arsenic in drinking water to comply with more stringent environmental regulations.     

水中Mg~(2+)的测试管快速测定

研制了一种测定水中Mg2 + 的测试管 ,测定范围为 0 .5mg/L～ 2 .0mg/L。该测试管适用于现场应急监测 ,具有快速、简便、抗干扰能力强和价格低廉等特点     

海河下游水体中DO与NH_3-N、COD_(Mn)相关关系探讨

本文应用近年来海河下游监测数据对ＤＯ与ＮＨ３Ｎ和ＣＯＤＭｎ进行一元线性回归，得到两回归方程：ＮＨ３Ｎ＝－１２８ＤＯ＋１０５４；ＣＯＤＭｎ＝－１１３ＤＯ＋１６９２。并经相关系数和回归系数显著性检验，表明在９９９％的置信水平下ＤＯ与ＮＨ３Ｎ和ＣＯＤＭｎ线性相关均极其显著     

Assessing the influence of altitude and temperature on biological monitoring of freshwater quality: A preliminary investigation

The effect of altitude and water temperature on biomonitoring of freshwater quality was examined along an unpolluted area (36 km in length) of the upper Río Tajo (central Spain). The macrobenthic and fish communities were studied, and the Biological Monitoring Water Quality (BMWQ) method was applied. As expected, values of altitude and temperature respectively decreased and increased with increasing distance from the river source; these two physical parameters exhibited a negative and significant (P<0.05) correlation coefficient between them. However, despite evident changes in the functional structure of both aquatic communities along the study area, BMWQ scores were similar at all sampling sites. Pearson correlation coefficients between physical and biological parameters were not significant (P>0.05). The BMWQ index only exhibited significant (positive) correlation coefficients with macrobenthic and fish biomasses, indicating that freshwater quality could affect the biological production of fluvial ecosystems. It is concluded that biomonitoring of freshwater quality may be independent of the influence of altitude and water temperature at local spatial scales. Nonetheless, further investigations would be needed to clearly differentiate between the effects of anthropogenic and natural causes on biological monitoring at larger spatial scales.