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391.
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针对集约化农业过量施入化肥农药等引起的土壤质量退化问题,采用造纸黒液废物提取的低聚木糖作为土壤调理剂。通过室内土壤培养,研究不同低聚木糖施用量(0.01%、0.05%、0.1%和0.2%)对土壤微生物数量和脲酶活性的影响。通过番茄盆栽实验,并设置添加0.1%商品生物有机肥处理作比较,研究不同低聚木糖施用量对土壤微生物量氮磷、脲酶和磷酸酶活性的影响。结果表明,低聚木糖可以提高土壤细菌、放线菌数量、土壤脲酶和磷酸酶活性。低聚木糖也显著增加番茄各生长期土壤微生物量碳和磷含量,其中开花期时低聚木糖的促进作用最为明显。所有剂量处理中,以0.05%的低聚木糖添加量处理效果最为明显,且该处理效果也优于添加0.1%生物有机肥处理。低聚木糖作为土壤调理剂,能显著提高土壤微生物数量和酶活性,改善土壤生态系统,提高土壤质量,在农业上具有广阔的应用前景。 相似文献
393.
官金华 《中国环境管理干部学院学报》2012,(6):81-84
2009年,财政部拟定了新《高等学校会计制励(征求意见稿),要求核算能提供预算管理需要的预算收支信息,增加了与公共财政改革相关的会计核算内容,但高校会计制度(征求意见稿)与公共财政体制依然存在着衔接不当问题。从公共财政体制改革对高校会计的影响出发,解读了高校会计制度(征求意见稿)与财政改革的衔接性,分析了高校会计实务中存在的与公共财政改革不协调的问题,并提出了相应的解决措施。 相似文献
394.
我国加入世贸组织后,除了粮食安全、比较优势、竞争力等方面的影响研究外,农产品贸易开放对我国农业生产部门就业的影响一直令人关注,是具有比较优势的劳动密集型农产品出口带来更多就业创造,还是土地密集型农产品进口引致更多就业替代?本文运用1994-2009年数据,对入世前后农产品贸易开放引致的农业就业效应进行全面系统的实证分析,并对在不同情形下我国未来贸易引致的农业就业替代效应的程度和方式进行了模拟分析。研究结果表明:入世后我国农产品贸易引致的农业就业效应呈现出更明显的就业净替代变化;同时,在技术水平不变的情况下,我国未来劳动密集型农产品的实际出口增速与平抑就业替代压力的"理想增速"相距甚远,未来土地密集型净进口所产生的农业就业替代量将在较大程度上超过劳动密集型净出口创造的就业机会,我国农业就业整体"净替代"的趋势可能将长期持续。 相似文献
395.
A rapid and high-throughput quantum dots bioassay for monitoring of perfluorooctane sulfonate in environmental water samples 总被引:1,自引:0,他引:1
Zhang J Wan Y Li Y Zhang Q Xu S Zhu H Shu B 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1348-1353
Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPARα), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPARα-RXRα. It can be determined indirectly by immobilizing PPARα-RXRα-PFOS complex to another plate coated with PPARα antibody and subsequent measuring the level of PPARα-RXRα by using biotin-modified PPARα-RXRα probes-quantum dots-streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L−1 with linear range between 2.5 ng L−1 and 75 ng L−1. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS. 相似文献
396.
A pilot biotrickling filter (BTF) packed with ZX02 fibrous balls as packing material was tested for the treatment of ammonia (NH3) released from a composting plant of dairy manure. In order to investigate the effects of three compost aeration modes (mode Co-I, Co-II and In-II) on the NH3 removal efficiency, a field experiment was continuously carried out for more than eight months. The results demonstrated that under the intermittent aeration mode (In-II), the NH3 removal efficiency reached 99.2 ± 0.1% when the inlet NH3 concentration was 7.5-32.3 mg m−3 (9.8-42.5 ppmv). The maximum and critical elimination capacity of the biotrickling filter was 22.6 and 4.9 g NH3 m−3 h−1, respectively. The effluent concentration of NH3 was lower than 1.0 mg m−3, which meets the first class discharge standards of GB14554-93. When the concentration of free ammonia in the trickling liquid was varied from 0.1 to 0.4 mg L−1, the nitrification yield was between 47.9% and 103.8%. In addition, the optimum liquid tricking velocity (LTV) of the biotrickling filter was 0.5 m3 m−2 h−1 for low inlet concentrations and 2.2 m3 m−2 h−1 for high inlet concentrations. Therefore, the use of the biotrickling filter for the compost under the third aeration mode (In-II) yielded an effective optimum NH3 removal and reduced the nitrogen loss in the compost. 相似文献
397.
This study aims to investigate levels of POPs in meat, edible oils, nuts, milk and wine collected from Hong Kong. Naphthalene, pp-DDE, beta-, gamma-HCH and PBDE 47 were detected in most of the food items. Goose liver accumulated the highest PAHs (47.9 ng g−1 wet wt), DDTs (25.6), HCHs (13.0), PCBs (4.17), PBDEs (468 pg g−1 wet wt) among all the selected food. Meat and nut groups had significant (p < 0.01 or 0.05) correlations between lipid contents and concentrations of PAHs (meat: r = 0.878), HCHs (meat: r = 0.753), DDTs (meat: r = 0.937; nuts: r = 0.968) and PCBs (meat: r = 0.832; nut: r = 0.946). The concentrations of DDTs, HCHs and PCBs in vegetable oil were lower, but HCHs in fish oil were higher, when compared with other countries. The concentrations of PAHs, DDTs, PCBs and PBDEs in food tested in the present study were all below various safety guidelines. 相似文献
398.
Wang Q Wang L Chen X Rao KM Lu SY Ma ST Jiang P Zheng D Xu SQ Zheng HY Wang JS Yu ZQ Zhang R Tao Y Yuan J 《Environmental science and pollution research international》2011,18(6):987-996
Background
Di-(2-ethylhexyl) phthalate (DEHP) is a common plasticizer used in industrial and diverse consumer products. Animal studies indicate DEHP caused developmental, reproductive, and hepatic toxicities. However, human studies of the potential effects of DEHP are limited.Methods
The exposed site with a history of over 20 years of waste plastic recycling was located in Hunan Province, China. The reference site without known DEHP pollution source was about 50 km far away from the exposed site. In this study, 181 workers working in plastic waste recycling and 160 gender?Cage matched farmers were recruited. DEHP concentrations in water and cultivated soil samples, serum thyroid-stimulating hormone, malondialdehyde (MDA), superoxide dismutase (SOD), urinary 8-hydroxy-2??-deoxyguanosine (8-OHdG), and micronuclei frequency in human capillary blood lymphocytes were analyzed.Results
Mean levels of DEHP were greater in environment at the recycling site than at reference site (industry wastewater for the exposed: 42.43 ??g/l; well water: 14.20 vs. 0.79 ??g/l, pond water: 135.68 vs. 0.37 ??g/l, cultivated soil: 13.07 vs. 0.81 mg/kg, p?0.05 for all). The workers had higher median levels of MDA (3.80 vs. 3.14 nmol/ml) and urinary 8-OHdG (340.37 vs. 268.18 ??mol/mol creatinine) and decreased SOD activities (112.15 vs. 123.82 U/ml) than the reference group (p?0.01 for all). Multivariate analysis revealed that the history of working in waste plastic recycling was an independent risk factor for the increased urinary 8-OHdG levels in the male workers (p?0.01).Conclusions
The occupational DEHP exposure might contribute to oxidative deoxyribonucleic acid damage in the male workers. 相似文献399.
400.