Seasonal decline in reproductive performance varies with colony size in the fairy martin, <Emphasis Type="Italic">Petrochelidon ariel</Emphasis>

Reproductive success within populations often varies with the timing of breeding, typically declining over the season. This variation is usually attributed to seasonal changes in resource availability and/or differences in the quality or experience of breeders. In colonial species, the timing of breeding may be of particular importance because the costs and benefits of colonial breeding are likely to vary over the season and also with colony size. In this study, we examine the relationship between timing of breeding and reproductive performance (clutch size and nest success) both within and between variable sized colonies (n = 18) of fairy martins, Petrochelidon ariel. In four of these colonies, we also experimentally delayed laying in selected nests to disentangle the effects of laying date and individual quality/experience on reproductive success. Within colonies, later laying birds produced smaller clutches, but only in larger colonies. The general seasonal decline in nest success was also more pronounced in larger colonies. Late laying birds were generally smaller than earlier laying birds, but morphological differences were also related to colony size, suggesting optimal colony size also varies with phenotype. Experimentally delayed clutches were larger than concurrently produced non-delayed clutches, but only in larger colonies. Similarly, delayed clutches were more likely to produce fledglings, particularly later in the season and in larger colonies. We suggest that the reduced performance of late breeding pairs in larger colonies resulted primarily from inexperienced/low quality birds preferring to settle in larger colonies, possibly exacerbated by an increase in the costs of coloniality (e.g., resource depletion and ectoparasite infestations) with date and colony size. These findings highlight the importance of phenotype-related differences in settlement decisions and reproductive performance to an improved understanding of colonial breeding and variation in colony size.     

Evaluation of soil fertility using infrared spectroscopy: a review

Soil fertility is conventionally evaluated by soil properties such as C, N, and P contents. Evaluation of soil fertility is now becoming a routine work for soil management and crop production. However, laboratory-analysis based determination of soil properties is time and cost consuming, which is not suitable for precision agriculture. Here, infrared spectroscopy (IR) appears as an alternative and fast technique to measure soil fertility. The IR transmission method is generally used in soil qualitative analysis, while the IR reflectance can be used in soil quantitative analysis, and most of soil-related research is focused on reflectance spectroscopy. Infrared reflectance spectra, including diffuse reflectance spectra and total attenuated reflectance spectra, are involved in soil quantitative analysis. We observe an excellent performance of predicting soil C and N contents using IR spectra. Moreover, in most of cases the predictions of the contents of soil P, K, Ca, Mg, S, and some other microelements are satisfactory. Soil water, soil clays, and soil microbes can also be characterized and evaluated using IR spectroscopy. In recent years, a new method named infrared photoacoustic spectra was applied in soil analysis. Infrared-photoacoustic spectra is indeed more convenient for sample pretreatment and spectra recording, and the recorded soil spectra contain more useful information versus conventional reflectance spectroscopy. Though currently the application of infrared photoacoustic spectroscopy in soil analysis is limited, it appears promising to measure soil fertility. The application of infrared spectroscopy in soil fertility is largely dependent on spectra pretreatment and multivariate calibration due to strong interferences in the spectra. Partial least square (PLS) and artificial neural network (ANN) are two widely used mathematical tools in the prediction of soil properties, and more mathematical tools combined models will benefit the prediction performance. To make full use of soil infrared spectra, soil spectra library construction is needed in future, and a standard procedure should be first decided in the construction. Based on soil infrared spectra library soil fertility can be fast evaluated combining suitable mathematical model, which will play an important role in the sustainable agriculture.     

Application of different foliar iron fertilizers for enhancing the growth and antioxidant capacity of rice and minimizing cadmium accumulation

Environmental Science and Pollution Research - Iron (Fe) fertilizer can reduce cadmium (Cd) uptake and toxicity in rice, but the underlying mechanisms of Cd mitigation by different fertilizers are...     

虚拟现实技术在环境管理中的应用

简介虚拟现实技术的发展及其应用概况，对虚拟现实技术应用于环境管理的可行性及优越性进行了分析，并从区域环境规划、环境治理、环境决策、环境预测、环境数学与科研等方面对具体的应用进行了探讨。     

Formation characteristics of aerosol particles from pulverized coal pyrolysis in high-temperature environments

The formation characteristics of aerosol particles from pulverized coal pyrolysis in high temperatures are studied experimentally. By conducting a drop-tube furnace, fuel pyrolysis processes in industrial furnaces are simulated in which three different reaction temperatures of 1000, 1200, and 1400 degrees C are considered. Experimental observations indicate that when the reaction temperature is 1000 degrees C, submicron particles are produced, whereas the particle size is dominated by nanoscale for the temperature of 1400 degrees C. Thermogravimetric analysis of the aerosol particles stemming from the pyrolysis temperature of 1000 degrees C reveals that the thermal behavior of the aerosol is characterized by a three-stage reaction with increasing heating temperature: (1) a volatile-reaction stage, (2) a weak-reaction stage, and (3) a soot-reaction stage. However, with the pyrolysis temperature of 1400 degrees C, the volatile- and weak-reaction stages almost merge together and evolve into a chemical-frozen stage. The submicron particles (i.e., 1000 degrees C) are mainly composed of volatiles, tar, and soot, with the main component of the nanoscale particles (i.e., 1400 degrees C) being soot. The polycyclic aromatic hydrocarbons (PAHs) contained in the aerosols are also analyzed. It is found that the PAH content in generated aerosols decreases dramatically as the pyrolysis temperature increases.     

Development of a standard reference material containing 22 chlorinated hydrocarbon gases at 1 μmol/mol in nitrogen

A gas standard mixture containing 22 chlorinated hydrocarbons in high purity nitrogen was prepared using a two-step weighing method and a gasifying apparatus developed in-house. The concentration of each component was determined using a gas chromatograph with flame ionization detection (GC/FID). Linear regression analysis of every component was performed using the gas standard mixture with concentrations ranging from 1 to 10 μmol/mol, showing the complete gasification of volatile organic compound (VOCs) species in a selected cylinder. Repeatability was also examined to ensure the reliability of the preparation method. In addition, no significant difference was observed between domestic treated and imported treated cylinders, which were conducive to reduction of the cost of raw materials. Moreover, the results of stability testing at different pressures and long-term stability tests indicated that the gas standard at 1 μmol/mol level with relative expanded uncertainties of 5% was stable above 2 MPa for a minimum of 12 months. Finally, a quantity comparison was conducted between the gas standard and a commercial gas standard from Scott Specialty Gases (now Air Liquide America Specialty Gases). The excellent agreement of every species suggested the favorable accuracy of our gas standard. Therefore, this reference material can be applied to routine observation of VOCs and for other purposes.     

Does industrial collaborative agglomeration improve environmental efficiency? Insights from China’s population structure

Environmental Science and Pollution Research - Nowadays, the development of green economy and the improvement of environmental efficiency have been a hotspot in both academia and industry....     

利用质子化的水杨醛接枝壳聚糖吸附水中硫酸根

以水杨醛（邻羟基苯甲醛）接枝壳聚糖为基础制备出质子化改性壳聚糖,研究其对硫酸根离子（SO24-）的吸附性能。通过静态吸附实验进行了吸附条件的优化以及吸附等温方程研究,用扫描电镜（SEM）和红外光谱（FTIR）对产物进行了表征,并对吸附机理进行了初步探讨。优化的吸附条件为：吸附时间为40min,SO24-溶液初始浓度500mg／L,pH值为5．0,反应温度为35℃;吸附等温方程研究表明,吸附过程符合Langmuir型,吸附容量为107．53mg／g。SEM和红外光谱分析表明：SO24- 主要是被吸附到壳聚糖的氨基上的。     

附载型吸附剂对煤油中硫醇类硫的吸附特性

利用浸渍-焙烧法制备的载有铜、铅或锰的附载型吸附剂吸附煤油中的硫醇类硫,脱硫醇效果显著。制备的各种吸附剂吸附硫醇类硫的过程中的液膜扩散,颗粒内部的扩散性存在差异。等温吸附曲线显示载铜氧化铝吸附剂对硫醇的吸附遵从Langmuir方程,载铅氧化铝吸附剂对硫醇的吸附可用Freundlich方程拟合。流量为每小时1个床体积的固体床动态吸附结果表明,载铅氧化铝吸附剂吸附过程到达穿透点(硫醇类硫浓度为2.55mg/L)的连续过液量为97个床体积。     

Highly efficient decolorization of Malachite Green by a novel Micrococcus sp. strain BD15

Purpose

Malachite Green (MG) is used for a variety of applications but is also known to be carcinogenic and mutagenic. In this study, a novel Micrococcus sp. (strain BD15) was observed to efficiently decolorize MG. The purposes of this study were to explore the optimal conditions for decolorization and to evaluate the potential use of this strain for MG decolorization.

Methods

Optical microscope and UV?Cvisible analyses were carried out to determine whether the decolorization was due to biosorption or biodegradation. A Plackett?CBurman design was employed to investigate the effect of various parameters on decolorization, and response surface methodology was then used to explore the optimal decolorization conditions. Kinetics analysis and antimicrobial activity tests were also performed.

Results

The results indicated that the decolorization by the strain was mainly due to biodegradation. Concentrations of MG, urea, and yeast extract and inoculum size had significantly positive effects on MG decolorization, while concentrations of CuCl₂ and MgCl₂, and temperature had significantly negative effects. The interaction between different parameters could significantly affect decolorization, and the optimal conditions for decolorization were 1.0 g/L urea, 0.9 g/L yeast extract, 100 mg/L MG, 0.1 g/L inoculums (dry weight), and incubation at 25.2°C. Under the optimal conditions, 96.9% of MG was removed by the strain within 1 h, which represents highly efficient microbial decolorization. Moreover, the kinetic data for decolorization fit a second-order model well, and the strain showed a good MG detoxification capability.

Conclusion

Based on the results of this study, we propose Micrococcus sp. strain BD15 as an excellent candidate strain for MG removal from wastewater.