Download This Paper Open PDF in Browser Add Paper to My Library Share: Permalink Using these links will ensure access to this page indefinitely Copy URL Copy DOI

测定了250g/L嘧菌酯悬浮剂、50％醚菌酯可湿性粉剂、15％吡唑醚菌酯悬浮剂和22.5％啶氧菌酯悬浮剂4种常用甲氧基丙烯酸酯类杀菌剂对鸟、蜜蜂、家蚕、鱼、藻、溞和蚯蚓的急性毒性.结果显示:4种甲氧基丙烯酸酯类杀菌剂对蜜蜂的LD50(48 h)值均＞100μg a.i./蜂,急性毒性均为低毒,对鸟类的LC50(48 h)值分别为743、＞1 000、＞1 500和＞ 1 000mg a.i./kg体重,急性毒性均为低毒;对家蚕的LC50(48 h)值分别为430.28、＞2 000、31.61和345.48mg a.i./L,急性毒性均为低毒;对蚯蚓的LC50(48 h)值分别为19.84、＞100、＞100和＞ 100mg a.i./kg干土,急性毒性均为低毒;对斑马鱼的LC50(48 h)值分别为7.46、0.65、0.051和0.12mga.i./L,急性毒性分别为中毒、高毒、剧毒和高毒;对大型溞的EC50(48 h)值分别为0.59、0.22、0.067和0.018mg a.i./L,急性毒性分别为高毒、高毒、剧毒和剧毒;对绿藻的EC50(48 h)值分别为0.66、31.96、5.51和0.036mg a.i./L,急性毒性分别为中毒、低毒、低毒和高毒.综上,4种甲氧基丙烯酸酯类杀菌剂对陆生生物毒性较低,但对水生生态系统存在潜在的风险.

Chemical fertilizer (CF)-oversupplied soils in intensive agricultural systems are typically abandoned due to loss of fertility and productivity. In this study, we investigated the potential of organic-mineral fertilizer (OMF), produced by a combination of organic matter, potassium (K)-feldspar powder and microbial fermentation, to alleviate the same in purslane cultivation. A gradient dose of OMF was applied to CF-oversupplied soils and purslane was grown in it and the alterations in soil physic-chemical parameters and enzyme activities along with purslane nutritional traits were analysed after 80 days. From the results, soil with excessive CF exhibited a sharp decrease in pH and increased electrical conductivity (EC); further, the activities of enzymes, such as urease, alkaline phosphatase and carbonic anhydrase (CA), showed an abrupt decrease. When a gradient dose of OMF (67, 134 and 200 g kg−1 soil based on the previous research in the lab) was applied to the CF-oversupplied soil, their available K content was significantly higher than the CF-oversupplied treatment and control. Additionally, the contents of total carbon and active organic carbon (AOC) were highest in treatment group OMF3 + CF (200 g of OMF kg−1 soil). The nutritive contents of purslane, such as soluble sugar and total flavonoids, and relative contents of ω-3 polyunsaturated fatty acid (PUFA) etc. showed a significant increase when compared with control, while the anti-nutritive compounds, such as nitrates and soluble oxalic acid, decreased. The positive effects on the soil quality traits and purslane growth and nutritive quality suggest the OMF treatment might be a promising approach for sustainable crop production and soil remediation in CF-oversupplied soil.

全国八大生态脆弱区中半数都分布在长江经济带范围内,近20年的快速城镇化进程忽视了经济发展与资源环境承载力的协调性,导致生态脆弱区生态系统更加退化、生态服务功能下降.本文分析了长江经济带4个典型生态脆弱区生态退化问题以及生态修复和保护的现状,并提出了对策建议.针对长江经济带不同脆弱区特征,要因地制宜,分别制定生态恢复的基本措施和技术对策;有序实施生态修复保护工程,促进生态系统整体治理;落实生态保护与修复的监督管理机制,强化后续监管;支持长江经济带生态保护修复技术研究,推进科技创新引领;加快生态修复和环境保护立法工作,构建长江经济带生态修复和保护的长效机制.

The pollution of antibiotic resistance genes (ARGs) in livestock farms is a problem which need to be paid more attention to, due to the severe resistance dissemination and the further human health risk. In this study, all the relevant exposure matrices (manure, soil and water) of sixteen animal farms in Southeastern China were sampled to determine twenty-two ARGs conferring resistance to five major classes of antibiotics including tetracyclines, sulfonamides, quinolones, aminoglycosides, and macrolides. The results showed that the spread property of sul genes was most extensive and strong, followed by tet and erm genes. The abundance of tet genes expressing ribosomal protection proteins (tetM, tetO, tetQ, tetT and tetW) was higher than that expressing efflux pump proteins (tetA, tetC, tetE and tetG) in each type of samples. The high abundance and frequency of ermB gene in the matrices should be paid more attention, because macrolides is a major medicine for human use. For manures, it was found that the similar ARGs distribution rules were existing in poultry manure or porcine manure samples, despite of the different origins of these two types of livestock farms. Meanwhile, it was interesting that the distribution rule of tet genes in animal manure was nearly the same as all the ARGs. For soils, the result of nonmetric multi-dimensional scaling (NMDS) analysis showed that the pollution of ARGs in the soils fertilized by poultry and cattle manures were more substantial in northern Jiangsu, but no significant ARGs diversity was observed among porcine manured soils of five different regions. Furthermore, most ARGs showed significant positive relationships with environmental variables such as concentration of sulfonamides, tetracyclines, Cu, Zn and total organic carbon (TOC). The pollution profile and characteristics of so many ARGs in livestock farms can provide significative foundation for the regulation and legislation of antibiotics in China.

With the large-scale development of aquaculture industry,a large number of roxarsone( ROX,a kind of veterinary drug)-containing manure are being applied to vegetables as organic fertilizer. Whether ROX's large application will reduce the yield and quality of vegetables or not is noteworthy. The common leafy vegetable, Amaranthus mangostanus,was selected in this paper to suspect these effects. Results showed that ROX treatment inhibited the elongation of radicles and root systems which led to the decrease of the height,leaf area and biomass of seedlings. The results of chlorophyll fluorescence parameters( Fv / F0 and Fv / Fm) implied that ROX could damage the PSII structure and function of A. mangostanus leaves,which led to a decrease in photosynthetic capacity. Contents of reductive ascorbic acid( As A),glutathione( GSH) and anthocyanin increased with the increase of ROX,While contents of inorganic nutrient,soluble sugar and soluble protein were relatively stable. ROX treatment promoted the accumulation of As and nitrate in A. mangostanus. The As content in the edible parts was beyond the arsenic content limits of food and vegetable in WHO,FAO and China,and the nitrate content had reached moderate and severe pollution level. Given all that,veterinary drug ROX residue in the soil,will not only inhibit seed germination and seedling growth,reduce vegetables' yield,but also may reduce the vegetables' quality,improve human cancer risk through the accumulation of arsenic and nitrate.

With the increase of focus on food safety,copper agents which have the characteristics of pollution-free,no re?sistance etc. are widely used in organic agricultural production. Whether the extensive application of copper agents will bring influence on the yield and quality of foods or not is noteworthy. To inspect this influence,the changes of seed ger?mination,seedling growth and vegetable quality of Ipomoea aquatic under CuSO4 processing will be assayed in this pa?per.Results showed that CuSO4 treatment not over 1 mM had no obvious effect on seed germination rate,but would re?duce seed germination quality. CuSO4 treatment not over 9 mM had no obvious effect on seedling growth,photosynthesis, yield and nutrient content. CuSO4 treatment would increase copper accumulation in I. aquatic seedlings,and copper would accumulate preferentially in roots. Copper content in leaves and stems in the treated I. aquatic seedlings would not exceed the national standard,but it would exceed the standard in roots when CuSO4 was not less than 3 mM. CuSO4 treatment would reduce the nitrate reductase activities which led to the nitrate accumulation to the severe pollution level in I. aquatic seedlings. This would reduce the vegetable quality and enhance the human cancer risk.

The effect of residual veterinary tetracycline on the formation of drug-resistant bacteria and corresponding resistance genes was investigated. During the research, the soil with long-term application of pig manure containing residual tetracycline was collected in autumn and summer respectively in the farmland around a certain pig farm in Shuyang City, Huang Huai area, north of Jiangsu province. At the same time, soils without application of pig manure in the farmland of this area were collected as the reference sample. Composition of drug-resistant bacteria in all soil samples was analyzed and three common tetracycline-resistance genes (tetA, tetC, tetE) were studied by PCR as well. During the research, 59 drug-resistant bacteria belonging to 13 bacterial genus respectively were separated from the soil sample collected in autumn while 35 drug- resistant bacteria belonging to 10 bacterial genus respectively were separated from the soil sample collected in summer and as for the reference sample, 3 drug-resistant bacteria belonging to 1 bacterial genus (Streptomyces) were separated with pathogenic bacteria up to 38.14% of total drug-resistant bacteria. PCR result showed that resistance genes were detected in all drug-resistant bacteria and tetC accounted for the most. At the same time, the residual tetracycline in the soil which was in a range of 41.1-61.9 microg x kg(-1) correlated with the amount of resistance genes (4.63 x 10(5)-37.42 x 10(5) copies x g(-1)). Besides, the climate was found accelerating the formation of drug-resistant bacteria and resistance genes.

To study the effects of copper agents on the yield and quality of vegetables, Amaranthus mangostanus was selected as materials to analyze the changes of seed germination, seedling growth, and quality with bluestone ( CuSO4 ) treatment. 0. 05-1. 50 mmol/L CuSO4 had no significant effect on the seed germination rate, but inhibited the radicle and hypocotyl elongations of A. mangostanus germinating seeds, and the seed vigor index dropped sharply. Seedlings under 1. 00-15. 00 mmol/L CuSO4 treatment showed no obvious toxic symptoms, but their heights, leaf areas, biomass, root ac-tivities, photosynthetic pigment contents, maximal fluorescence, maximal fluorescence efficiencies and PSⅡ potential ac-tivities decreased with the increase of CuSO4 concentration, and copper contents in different organs and malondialdehyde contents, electrical conductivities, O2·- contents, H2 O2 contents, nitrate contents and nitrate reductase activities in leaves increased with the increase of CuSO4 concentration.

To assess the toxic effects of herbicide paraquat (1,1′-dimethyl-4,4′-bipyridinium dichlorine) on the algal ecosystem, the growths of four cyanobacterial strains (Microcystis aeruginosa XW01, M. aeruginosa PCC7806, Merismopedia sp., and Synechocystis PCC6803) and two green alga strains (Chlorella pyrenoidosa, Chlorococcum sp.472) were measured with different concentrations of paraquat. The Median Effect Concentration (EC50), Lowest Observable Effective Concentration (LOEC), No Observable Effective Concentration (NOEC) and Chronic Value (ChV) of paraquat to the six strains were calculated. The experimental results showed that cyanobacteria were more sensitive than green algae to paraquat, and 96 h-EC50 value of C. pyrenoidosa was 7.4 times higher than the value of M. aeruginosa XW01. Longer exposure time displayed higher toxicity.

Previous research has shown that the geographical distribution patterns of freshwater fishes and amphibians have been influenced by past climatic oscillations in China resulting from Pleistocene glacial activity. However, it remains unknown how these past changes have impacted the present-day distribution of Chinese freshwater crabs. This work describes the diversity and endemism of freshwater crabs belonging to Sinopotamon, a highly speciose genus endemic to China, and evaluates its distribution in terms of topography and past climatic fluctuations. Species diversity within Sinopotamon was found to be concentrated in an area from the northeastern edge of the Yunnan-Guizhou Plateau to the Jiangnan Hills, and three areas of endemism were identified. Multiple regression analysis between current climatic variables and Sinopotamon diversity suggested that regional annual precipitation, minimum temperature in the coldest month, and annual temperature range significantly influenced species diversity and may explain the diversity patterns of Sinopotamon. A comparison of ecological niche models (ENMs) between current conditions and the last glacial maximum (LGM) showed that suitable habitat for Sinopotamon in China severely contracted during the LGM. The coincidence of ENMs and the areas of endemism indicated that southeast of the Daba Mountains, and central and southeastern China, are potential Pleistocene refuges for Sinopotamon. The presence of multiple Pleistocene refuges within the range of this genus could further promote inter- and intraspecific differentiations, and may have led to high Sinopotamon species diversity, a high endemism rate and widespread distribution.

To monitor the pollution of estriol,17β-estradiol,17α-estradiol and estrone from animal manure in vegetable,an analytic method with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS / MS) was established.The samples were extracted with acetonitrile by ultrasonic,cleaned up by Agilent-C 18 column solid phase extraction,concentrated in a gentle nitrogen stream,and were analyzed by HPLC-MS / MS in gradient elution.A perfect separation for estriol,17β-estradiol,17α-estradiol and estrone was achieved with their respective retention time of 2.6 min,8.2 min,8.9 min and 9.9 min,and the calibration curves were linear in concentration range of 10-1 000 ng / ml and correlation coefficients above 0.999.At the concentrations of 50 μg / kg,100 μg / kg and 500 μg / kg,the average recoveries of estriol,17β-estradiol,17α-estradiol and estrone were 75.15%-86.32%,73.82%-83.21%,72.01%-81.33% and 81.08%-90.35%,respectively,with the relative standard deviation(RSD) of 1.03%-6.19%.The quantification limit of the method for the spiked samples was both 10 μg / kg for 17β-estradiol and 17α-estradiol,5 μg / kg for estriol,and 1 μg / kg for estrone.These results indicate that this method can be used to simultaneously determine the residues of estriol,17β-estradiol,17α-estradiol and estrone in vegetables.