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Li Zhansheng Zhao Hongxia Li Xintong Bekele Tadiyose Girma 《Environmental science and pollution research international》2022,29(17):24612-24622
Environmental Science and Pollution Research - Environmentally persistent free radicals (EPFRs) are an emerging class of environmental hazardous contaminants that extensively, stably exist in... 相似文献
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Asere Tsegaye Girma Verbeken Kim Tessema Dejene A. Fufa Fekadu Stevens Christian V. Du Laing Gijs 《Environmental science and pollution research international》2017,24(25):20446-20458
Environmental Science and Pollution Research - Contamination of drinking water with arsenic causes severe health problems in various world regions. Arsenic exists predominantly as As(III) and As(V)... 相似文献
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Bekele Tadiyose Girma Zhao Hongxia Yang Jun Chegen Ruth Gebretsadik Chen Jingwen Mekonen Seblework Qadeer Abdul 《Environmental science and pollution research international》2021,28(36):49507-49528
Environmental Science and Pollution Research - The ban and restriction of polychlorinated biphenyls (PCBs) and major brominated flame retardants (BFRs), including hexabromocyclododecane (HBCD) and... 相似文献
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Simultaneous adoption of integrated soil fertility management technologies in the Chinyanja Triangle,Southern Africa 下载免费PDF全文
Empirical scientific evidence indicates that there is still room for increasing food production by improving land productivity. This study aimed at identifying the key determinants that govern farmers’ decisions to adopt multiple components of integrated soil fertility management (ISFM) in a maize mixed cropping system of the Chinyanja Triangle, Southern Africa. Revealed preferences of ISFM components were collected from 320 randomly selected households and multivariate probit (MVP) model was used to analyse the simultaneous effects on adoption based on biophysical plot and household‐level socioeconomic attributes. The results show that farmers’ choices of a set of ISFM components are determined by a mix of factors that address the trade‐offs and synergies among them. Non‐farm income, moderate land quality perception, and education influence simultaneous technology adoption, while gender and crop loss increase the likelihood of farmers’ decisions to adopt independent options. Having other sources of income supports co‐adoption of inorganic fertilizer, residue incorporation, and crop rotation. Input/output market access, access to information, financial sources, and climate variability also play pivotal role in technology adoption. These results indicate that resource availability, learning costs, finances, and risk aversion need to be considered when designing and promoting ISFM technologies as a package. 相似文献
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Traditional occupancy–abundance and abundance–variance–occupancy models do not take into account zero-inflation, which occurs when sampling rare species or in correlated counts arising from repeated measures. In this paper we propose a novel approach extending occupancy–abundance relationships to zero-inflated count data. This approach involves three steps: (1) selecting distributional assumptions and parsimonious models for the count data, (2) estimating abundance, occupancy and variance parameters as functions of site- and/or time-specific covariates, and (3) modelling the occupancy–abundance relationship using the parameters estimated in step 2. Five count datasets were used for comparing standard Poisson and negative binomial distribution (NBD) occupancy–abundance models. Zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) occupancy–abundance models were introduced for the first time, and these were compared with the Poisson, NBD, He and Gaston's and Wilson and Room's abundance–variance–occupancy models. The percentage of zero counts ranged from 45 to 80% in the datasets analysed. For most of the datasets, the ZINB occupancy–abundance model performed better than the traditional Poisson, NBD and Wilson and Room's model. He and Gaston's model performed better than the ZINB in two out of the five datasets. However, the occupancy predicted by all models increased faster than the observed as density increased resulting in significant mismatch at the highest densities. Limitations of the various models are discussed, and the need for careful choice of count distributions and predictors in estimating abundance and occupancy parameter are indicated. 相似文献
6.
抗生素因具有抗菌谱广、杀菌性强等特点使其被广泛应用于人类医药、畜牧业、农业和水产养殖业。其进入水生生物体内后,会在药物代谢酶的作用下发生代谢转化,产生生态毒性。本研究采用鲫鱼肝微粒体体外孵育法,探究恩诺沙星细胞色素P450酶作用下的代谢转化过程,并通过代谢抑制实验确定关键的代谢酶。实验结果表明,恩诺沙星体外代谢过程符合一级动力学方程,当恩诺沙星暴露浓度为1 mg·L-1时,其在肝微粒体中的消除速率常数k最大为0.00303 min-1,半衰期t1/2最短为228.8 min,应用HPLC-MS/MS技术,检测到了恩诺沙星脱乙基产物和羟基化产物;代谢抑制实验结果表明,CYP3A4在恩诺沙星代谢过程中起主要作用,是恩诺沙星代谢的关键酶。本研究结果为深入了解恩诺沙星在水生生物体内的代谢转化及其生态风险提供了基础数据。 相似文献
7.
Allan J. Komakech Noble E. Banadda Joel R. Kinobe Levi Kasisira Cecilia Sundberg Girma Gebresenbet 《Journal of the Air & Waste Management Association (1995)》2014,64(3):340-348
In Kampala, Uganda, about 28,000 tons of waste is collected and delivered to a landfill every month. Kampala Capital City Authority (KCCA) records show that this represents approximately 40% of the waste generated in the city. The remaining uncollected waste is normally dumped in unauthorized sites, causing health and environmental problems. However, the organic fraction of domestic waste can provide an opportunity to improve livelihoods and incomes through fertilizer and energy production. This study characterized the municipal waste generated in Kampala and delivered to Kiteezi landfill between July 2011 and June 2012, that is, covering the dry and wet months. On each sampling day, waste was randomly selected from five trucks, sorted and weighed into different physical fractions. Samples of the organic waste from each truck were analyzed for total solids, major nutrients, and energy content. During the wet months, the waste consisted of 88.5% organics, 3.8% soft plastics, 2.8% hard plastics, 2.2% paper, 0.9% glass, 0.7% textiles and leather, 0.2% metals, and 1.0% others. During the dry months, the waste consisted of 94.8% organics, 2.4% soft plastics, 1.0% hard plastics, 0.7% papers, 0.3% glass, 0.3% textile and leather, 0.1% metals, and 0.3% others. The organic waste on average had a moisture content of 71.1% and contained 1.89% nitrogen, 0.27% phosphorus, and 1.95% potassium. The waste had an average gross energy content of 17.3 MJ/kg. It was concluded that the organic waste generated can be a suitable source of some plant nutrients that are useful especially in urban agriculture.
Implications:?The result of the waste characterization in Kampala was found to be significantly different from that obtained for other Sub-Saharan African (SSA) cities, showing that studies assuming average values for the waste fractions are likely to result in erroneous results. Furthermore, no reduction in organic fraction of the waste was noticed when compared with a study done two decades ago in spite of greatly improved economic status of Kampala city, a finding that is not in agreement with several other similar studies done for other SSA cities. 相似文献
8.
Gemeda Fekede Terefe Guta Dawit Diriba Wakjira Feyera Senbeta Gebresenbet Girma 《Environmental science and pollution research international》2021,28(10):12382-12396
Environmental Science and Pollution Research - Industrial wastes have been increasingly discharged into water and soil, and causing environmental pollution in Ethiopia. This study examined the... 相似文献
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Extending livestock grazing to the steep slopes has led to unstable grazing systems in the East African Highlands, and new
solutions and approaches are needed to ameliorate the current situation. This work was aimed at studying the effect of livestock
grazing on plant attributes and hydrological properties. The study was conducted from 1996 to 2000 at the International Livestock
Research Institute at Debre Ziet Research Station. Two sites were selected: one at 0–4% slope, and the other at 4–8% slope.
The treatments were: (1) no grazing (control); (2) light grazing, 0.6 animal unit months per hectare (aum/ha); (3) moderate
grazing, 1.8 aum/ha; (4) heavy grazing, 3.0 aum/ha; (5) very heavy grazing, 4.2 aum/ha; (6) initially plowed and continuously
very heavily grazed, 4.2 aum/ha. The result showed that species richness, infiltration rate, bare ground, and soil loss significantly
varied with grazing pressure. Species richness was higher in grazed plots compared to nongrazed plots. Biomass yield improved
on heavily grazed plots as cow dung accumulated over years. Cynodon dactylon plant species persisted with livestock grazing pressure in both sites. Infiltration rate improved and soil erosion declined
in all treatments after the first year. 相似文献