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Microbial community and phosphorus forms in response to simulated climate warming were studied by high-throughput sequencing and 31 P nuclear magnetic resonance( 31 P-NMR) respectively, which were from wetland soils in constructed microcosm columns. The results revealed that relative abundances of Firmicutes, Clostridia, Clostridiales, Clostridiaceae and Clostridium were significantly decreased by 65%-98%, 69%-87%, 67%-87%, 73%-97% and 74%-93% under warming condition respectively, suggesting warming had a significant inhibitory effect on the bacterial lineage from Firmicutes to Clostridium at different taxonomic level. Particularly, principal coordinate analysis and cluster analysis also demonstrated warming had a significant effect on microbial community structure with obvious separation of samples between control and warmed groups from each wetland column site. Phosphorus forms were dominated by phosphomonoester and orthophosphate in each wetland column soil, which were significantly increased and decreased by 275% and 20% in XX wetland column soil respectively. Similarly, phosphomonoester and polyphosphate were also found to be increased and decreased by 85% and 49% in JH wetland column soil respectively, indicating that phosphorus forms in response to warming had soil heterogeneity. Canonical correspondence analysis showed that obvious changes in microbial community composition had significant effects on phosphorus forms under warming condition.

There is a growing attention on the environmental pollution and loss of potential regeneration of resources due to the poor handling of organic wastes, while earthworm vermicomposting and larvae bioconversion are well-known as two promising biotechnologies for sustainable wastes treatments, where earthworms or housefly larvae are employed to convert the organic wastes into humus like material, together with value-added worm product. Taken earthworm ( Eisenia foetida) and housefly larvae ( Musca domestica) as model species, this work illustrates fundamental definition and principle, operational process, technical mechanism, main factors, and bio-chemical features of organisms of these two technologies. Integrated with the physical and biochemical mechanisms, processes of biomass conversion, intestinal digestion, enzyme degradation and microflora decomposition are comprehensively reviewed on waste treatments with purposes of waste reduction, value-addition, and stabilization.

Healthy wetland system is regarded as an effective way for biological remediation of non-point source pollutants. A case field investigation on phosphorus (P) status of overlying water and sediment was carried out for Xiazhuhu wetland located in Northern Zhejiang Province, China. A static wetland microcosm experiment was conducted to understand the characteristics and mechanisms related to P exchanging, P forms changing, and water quality impact across the interface of water and sediment. Field investigation showed that total P (TP) concentrations of sediments were found from 0.187 mg x g(-1) to 0.591 mg x g(-1), and TP in overlying water reached from 0.022 mg x L(-1) to 0.718 mg x L(-1) where the seasonal concentration variations of TP, dissolved P (DP), and particulate P (PP) were commonly found in order as winter > summer > spring > fall. Fed by synthetic solution containing P levels of 0.0 - 10.5 mg x L(-1), a 35-day-lasting microcosm study showed that P retention by sediments could be divided into three basic phases in order, i.e., buffer reaction, rapid adsorption, and slow adsorption. Under a typical stress concentration of 1.0 mg x L(-1) in overlying water, the increment of P tanks in different forms was found as NH4 Cl-P (0.0%), Fe-P/Mn-P (around 20%), NaOH-TP (around 66%, mainly as the form of Al-P), Ca-P (1.9%), and Res-P (11.3%), on the condition of Xiazhuhu wetland under low water season. Application of Al to wetland would increase the capacity of sediment P retention in Xiazhuhu wetland.

The wastewater from animal farms in China is threatening the quality and security of local water environment. In the laboratory scale, a traditional SBR (A/O) and a denitrifying phosphorus-accumulating organisms (DNPAO) sequencing batch reactor (SBR) in biologically removing nutrients and organic matters from swine manure were investigated in this study. When piggery wastewater was directly treated with a traditional SBR, the efficiency was low with unstable working state, the reduction of TN, TP and BOD5 reached 89.08%, 86.04% and 93.88%, respectively. While it performs a good effect in treating high density of piggery wastewater using DNPAO SBR technology, with the help of low-density aeration, two-step of influent feeding and two circulations of anaerobic-anoxic-anaerobic-anoxic (An/Ax2), the reduction of TN, TP and BOD5 reached the maximums of 93.95%, 99.26% and 99.93%, respectively. The specific operation of (An/Ax2) SBR contributed both low concentrations and limited export loads of NO3-. The temporal curves of ORP, pH and DO over time could be indicators for simultaneous removals of nitrogen and phosphorus along with biodegradation of organic matter during this specific SBR running. A pilot-scale investigation was recommended to further testify the feasibility and efficiency of this kind of SBR under the real-world condition.

Loss of life expectancy (LLE) was used to evaluate and quantitate the health risk caused by carcinogen and non-carcinogen pollutants, and was proposed as a new method to compare the environmental health risk of different pollutants. The environmental health risks exposed by 6 major environmental pollutants in China, i.e., arsenic, DDTs, BaP, lead, cadmium and mercury, were evaluated and compared by using LLE. The LLE caused by carcinogen pollutants such as arsenic, DDTs and BaP are 3.6 d, 2.2 d and 12.1 d respectively, while the corresponding values caused by non-carcinogen pollutants such as lead,mercury and cadmium are 1.1 d, 1.7 d and 5.8 d respectively. Based on the studies published before, the rank of the health risk of the selected six environmental pollutants is BaP > cadmium > arsenic > DDTs > mercury > lead. The results reveal that the LLE can be utilized as a new index to evaluate and quantitate the health risk, and the environmental health risk caused by carcinogen and non-carcinogen pollutants can be compared within an unitive criterion by LLE.

Using a multi-layer soil column device, the effect of new nitrification inhibitor DMPP (3,4-dimethyl pyrazole phosphate) on nitrogen leaching was studied for understanding the nitrogen vertical transformation and lowering the nitrogen leaching losses. The results indicate that, within 60 days of experiment, the regular urea added with 1% of DMPP can effectively inhibit the ammonium oxidation in the soil, and improve the concentration of NH4(+) -N in soil solution over the 20 cm tilth profile, while decline the concentrations of NO3(-) -N and N2(-) -N. No obvious difference is found on NH4(+) -N concentrations collected from deep layer soil solution under 20 cm between regular urea and the urea added with 1% of DMPP. There is also no significant difference for the NH4(+) -N and NO3(-) -N in the soil solution of deep layer under 40 cm among the treatments of urea by adding with 1% of DMPP within 60 days. So DMPP could be used as an effective nitrification inhibitor to control ammonium oxidation, decline the nitrate leaching losses, minimize the underground water pollution risk and be beneficial for the ecological environment.