Adsorption mechanism of styryl phosphonate ester as collector in ilmenite flotation

A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that SPE exhibited a stronger collecting ability for ilmenite than the traditional collector styrene phosphonic acid(SPA). Zeta potential measurements revealed that both SPE and SPA could negatively shift the zeta potential of ilmenite, while SPE had more effects than SPA, suggesting the stronger adsorption of SPE. The analysis of X-ray photoelectron spectroscopy confirmed the chemisorption of SPA and SPE onto the Fe/Ti sites of ilmenite. According to frontier orbital theory, the chemical activities of SPE are greater than those of SPA. The partial densities of states analysis indicated that the PO—H groups of the collectors could interact with the Ti/Fe atoms of the ilmenite surface to generate a stable four-membered ring. The bonding model of the collector and(104) ilmenite surface showed that the adsorption energy of SPE was higher than that of SPA. Overall, SPE presented a better collecting ability and interaction effect for ilmenite flotation than SPA, and had the potential to replace SPA in the industry.

Distribution characteristics and environmental risk assessment following metal(loid)s pollution incidents at Southwest China mining site

Limited information is available on long-term effects of metal(loid)s pollution incidents. Here, we analyze the distribution characteristics and quantification of elements in the Southwest China Keda mining site, which is one of the most populated sites and enables human health and ecological risk assessments of elemental pollution. The results on modified degree of contamination indicated that the soil and sediment were highly contaminated near Dahu Lake.The health risk of children was almost 2.5 times that of adults in surface water, and 7.1 times in soil, respectively.Moreover, Tl and As were the main health risk contributors in surface water and soil, respectively, and As posed the highest ecological risk both in soil and sediment. These results indicated the potential impact of toxic metal(loid)s on the health of residents and environment. Hence, more scientific attention and proper management need to be paid to this environmental challenge in the future.

Net Horizontal Payments for Ecosystem Services: An Application in the Beijing-Tianjin-Hebei Region of China

Payments for ecosystem services(PES) are one kind of important tool for environmental protection, and have been widely studied by international scholars and conservationists. Based various definitions of PES from recent articles, we have outlined four principles for PES: parity, measurability, additionality and conditionality, and then have used these principles to develop a formula to calculate a standard for PES. Finding a way to use PES to achieve a win-win relationship between economic growth and environmental protection in the Beijing-Tianjin-Hebei Region(BTHR) is a key task for Chinese government. Synergetic development of BTHR has become a national strategy, like The Belt and Road Initiative. This article employed the formula we developed to calculate the net horizontal PES amounts that each provincial government within BTHR should pay. Our findings show that Beijing should have paid 10.44×10~9 Yuan(0.4% of Beijing’s GRP) and Tianjin 16.56×109 Yuan(0.93% of Tianjin’s GRP) to Hebei in 2016.

Père David’s Deer(Elaphurus davidianus)in China:Population Dynamics and Challenges

The reintroduction of rare and endangered species is one of the most important approaches to conservation and ecosystem restoration,but it has still proven to be an adventurous undertaking and most reintroduction programmes fail,so successful demonstrations are needed.Père David’s deer(Elaphurus davidianus,Milu in Chinese)could be considered one of conservation’s great success stories,as this species’path on the road to extinction has been reversed by a combination of ex-situ conservation and successful re-introduction in China.The species had been consigned to an imperial hunting ground when the last Chinese herds were exterminated during the fall of the Qing Dynasty(1644-1912).Fortunately,a few of the last remaining individuals were sent to European zoos.From these animals,a herd was bred on the 14;Duke of Bedford’s estate,Woburn Abbey,and between 1985and 1987,and 38 Milu were donated back to China for re-introduction in Beijing Milu Park(BMP),the former imperial hunting ground.An additional 39 deer were released at Dafeng National Nature Reserve(DFNNR),Jiangsu Province in 1986.In both of these safe and protected locations,the Milu thrived allowing for over 700 Milu to be sent to a further 82 sites throughout the species’original Chinese range over the last 36 years.As a result,the Milu population totaled 9136 by 2021,with 2855 individuals now living back in the wild;while another 5681 individuals inhabit the DFNNR,and 186 reside in BMP.Wild Milu,however,still face significant conservation challenges.The population lacks genetic diversity,leading to severe inbreeding depression and carrying multiple risks,such as high miscarriage rates,a reduced lifespan,and susceptibility to disease.Environmental constraints such as pollution and habitat fragmentation further result in small,fragmented wild populations.Moreover,the species currently lacks a national level conservation master plan,the associated coordinated monitoring platforms,and breeding plans for China’s captive populations.Finally,there is now a lack of international cooperation in the conservation of this species.We therefore call for both a national-level conservation master plan in China and international cooperation to develop a shared database and germplasm databank covering Milu across all countries with ex-situ populations,as crucial steps for securing the long-term conservation of Milu and preventing it from ever becoming“extinct in the wild”again.

开展区域再生水循环利用 协同推进降碳、减污、扩绿、增长

生态环境部总工程师、水生态环境司司长,中国生态文明研究与促进会会长张波:所谓区域再生水循环利用,就是将达标排放的尾水通过人工湿地水质净化工程等生态措施进一步改善以后,在一定区域内统筹用于生态、生产、生活的再生水利用模式。这项工作不仅可以节约水资源,降低碳排放,还可以在缺水的地方形成一个个大水面,通过沿河环湖生态修复,进一步改善水环境、水生态,提升周边群众的获得感、幸福感。如果这篇文章做得好,我们就有可能把缺水地区的一些低价值空间改造成高价值空间。