华南兴国县影响土壤侵蚀时空动力学的环境因素   总被引：7，自引：0，他引：7  

WANG Ku  SHI Xue-Zheng  YU Dong-Sheng  SHI De-Ming  CHEN Jing-Ming  XU Bin-Bin  LIANG Yin  LI De-Cheng 《土壤圈》2005,15(5):620-627

By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination with the remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South China were analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The results showed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land under severe erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were more susceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between 7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. These areas deserve special attention in monitoring and controlling.  相似文献   

Synthesis and phytotoxicity of new ionic liquids incorporating chiral cations and/or chiral anions     

Bałczewski P  Bachowska B  Białas T  Biczak R  Wieczorek WM  Balińska A 《Journal of agricultural and food chemistry》2007,55(5):1881-1892

The aim of this work was to synthesize chiral ionic liquids as chiral solvents for organic synthesis and to evaluate the phyto(eco)toxicity of the new products and starting N-alkylimidazoles and their potential environmental influence on soil and plants. Chiral ionic liquids containing anions such as Cl-, Br-, TsO-, PF6(-), NO3(-), CF3SO3(-), and (+)- and (-)-C6H5CH(OH)C(O)O- were synthesized using (-)-(1R)-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-ethyl [(-)-(1R)-nopyl] halides (X = Cl, Br) and tosylate in 62-100% yields. The chloride 7 and the nitrate 13 ionic liquids possessed a toxicity dependent on the applied concentration. The lowest concentration causing a distinct reduction in plant germination/growth was 100 mg/kg. Spring barley better tolerated the ionic liquids (200 mg/kg) than common radish (100 mg/kg). The nitrate liquid did not exhibit an inhibiting effect on the germination ability of seeds. The starting N-methylimidazole used in lower concentrations (1 and 10 mg/kg of soil dry weight) was not phytotoxic, in contrast to higher doses (>1000 mg/kg).  相似文献   

Sediment load variability in response to climate and land use changes in a Carpathian catchment (Raba River,Poland)     

Szalińska  Ewa  Orlińska-Woźniak  Paulina  Wilk  Paweł 《Journal of Soils and Sediments》2020,20(6):2641-2652

Journal of Soils and Sediments - This study analyzes the variability of sediment loads under variant climate change and land use scenarios in a Carpathian catchment with a dam reservoir. The areas...  相似文献   

转Bt基因棉对棉田寄生物非亲和效应的研究     

余月书  杨益众  任璐  邵益栋  钱坤 《扬州大学学报(农业与生命科学版)》2004,25(2):65-67

采用分期接虫和分期回收的方法，研究常规棉与转基因棉品种棉铃虫寄生性天敌在不同棉花品种间的寄生作用。结果表明：棉铃虫第2～4代发生期以及卵期和幼虫期，转基因棉品种的棉铃虫卵、幼虫寄生率均显著低于常规棉品种。棉铃虫卵期的寄生蜂主要为拟澳洲赤眼蜂(Tricogramma confisum)，幼虫寄生蜂为棉铃虫齿唇姬蜂(Compoletis chlorideae)等。由此可见转基因棉对棉铃虫寄生性天敌存在非亲和效应。通过对转Bt基因棉国抗22及其亲本泗棉3号棉铃虫不同世代间卵、幼虫寄生率的纵向比较，发现同一品种棉花上不同世代间棉铃虫卵寄生率差异不显著，而幼虫寄生率差异显著。  相似文献   

基于优化的长短时记忆神经网络牧群采食量估测模型     

孟云琪  宣传忠  张蒙秦  樊先涛  布库 《安徽农业大学学报》2022,49(5):832

为了能够较为精准的估测牧群的采食量信息,提出一种基于遗传算法(genetic algorithm, GA)和长短时记忆神经网络（long short-term memory,LSTM）的牧群采食量估测模型。首先通过皮尔森系数法分析得出影响牧群的采食量的主要影响因子,以减少输入维度并解决信息冗余问题。在此基础上,构建基于 LSTM 神经网络算法的牧群采食量估测模型,并引入遗传算法来优化LSTM 神经网络模型参数来增加模型的可靠性。最后,利用该模型对牧群采食量进行估测。试验结果表明：该采食量估测模型各评价指标平均绝对误差(mean absolute error,MAE)、平均绝对百分比误差(mean absolute percentage error,MAPE)、以及均方根误差（root mean square error,RMSE）分别为2.982、9.85%和6.108。与单一的LSTM神经网络以及GRU神经网络模型相比,均优于其他模型;且该模型具有较好的估测性能和较强的泛化能力,能够为合理轮牧提供科学指导,对草地保护有一定的应用价值。  相似文献   

花生品种在巴州地区复播的综合评价     

陈晋瑞  杜珊珊  张磊磊  库尔班·牙生 《中国农学通报》2020,36(34):15-19

为筛选适宜在新疆巴音郭楞蒙古自治州复播种植的花生品种,在巴州地区复播种植6个花生品种,采用灰色关联度分析方法对10个农艺性状进行综合评价,并分析产量与各农艺性状的相关性。结果表明,综合评价中,各花生品种的等权关联度与加权关联度排列位次一致,排列位次为‘吉花4号’>‘四粒红’>‘DF05’>‘远杂9102’>‘DF06’>‘闽花6号’。‘吉花4号’综合性状评价优于对照‘四粒红’,适宜在新疆巴州地区复播条件下推广种植。而花生‘DF05’、‘远杂9102’、‘DF06’、‘闽花6号’的综合农艺性状劣于对照‘四粒红’,不建议推广种植。相关分析表明,产量与出仁率呈显著正相关。研究结果为巴州地区引进花生高产品种提供了材料基础和理论依据。  相似文献   

Design of Neural Network Predictor for the Physical Properties of Almond Nuts     

İkbal Eski  Bünyamin Demir  Feyza Gürbüz  Zeynel Abidin Kuş  Kadir Uğurtan Yilmaz  Mehmet Uzun  Sezai Ercişli 《Erwerbs-Obstbau》2018,60(2):153-160

In this study, an adaptive neuro fuzzy interface system (ANFIS) based predictor was designed to predict the physical properties of four almond types. Measurements of the dimensions, length, width and thickness were carried out for one hundred randomly selected samples of each type. With using these three major perpendicular dimensions, some physical parameters such as projected area, arithmetic mean diameter, geometric mean diameter, sphericity, surface area, volume, shape index and aspect ratio were estimated. In in a various Artificial Neural Network (ANN) structures, ANFIS structure which has given the best results was selected. The parameters analytically estimated and those predicted were given in the form of figures. The root mean-squared error (RMSE) was found to be 0.0001 which is quite low. ANFIS approach has given a superior outcome in the prediction of the Physical Properties of Almond Nuts.  相似文献   

Evaluation of the ability of colistin,amoxicillin (components of Potencil®), and fluoroquinolones to attenuate bacterial endotoxin‐ and Shiga exotoxin‐mediated cytotoxicity—In vitro studies     

Agnieszka Szuster‐Ciesielska  Renata Urban‐Chmiel  Andrzej Wernicki  Laurent Mascaron  Marek Wasak  Eric Bousquet 《Journal of veterinary pharmacology and therapeutics》2019,42(1):85-103

Escherichia coli is one of the major pathogens in humans and animals causing localized and systemic infections, which often lead to acute inflammation, watery diarrhea, and hemorrhagic colitis. Bacterial lipopolysaccharide (LPS) and Shiga exotoxins (Stx) are mostly responsible for such clinical signs. Therefore, highly effective treatment of E. coli infections should include both eradication of bacteria and neutralization of their toxins. Here, for the first time, we compared the in vitro ability of common antibiotics to decrease LPS‐ and Stx‐mediated cytotoxicity: colistin, amoxicillin (used separately or combined), enrofloxacin, and its metabolite ciprofloxacin. Three experimental scenarios were realized as follows: (a) the direct effect of antibiotics on endotoxin, (b) the effect of antibiotic treatment on LPS‐mediated cytotoxicity in an experiment mimicking “natural infection,” (c) the effect of antibiotics to decrease Stx2e‐mediated cytotoxicity. Two cell lines, A549 and Vero cells, were used to perform cytotoxic assays with the methyl tetrazolium (MTT) and lactate dehydrogenase leakage (LDH) methods, respectively. Colistin and amoxicillin, especially used in combination, were able to attenuate LPS toxic effect, which was reflected by increase in A549 cell viability. In comparison with other antibiotics, the combination of colistin and amoxicillin exhibited the highest boster or additive effect in protecting cells against LPS‐ and Stx2e‐induced toxicity. In summary, in comparison with fluoroquinolones, the combination of colistin and amoxicillin at concentrations similar to those achieved in plasma of treated animals exhibited the highest ability to attenuate LPS‐ and Stx2e‐mediated cytotoxicity.  相似文献   

松苗立枯病的研究Ⅰ、分布损失、征状类型、病原、和栽培影响     

吴友三  高雅  顾嗣芳  刘正南  陈锡芳  钟兆康 《植物保护学报》1963,2(2):179-186

松苗立枯病是东北地区针叶树育苗上的重要问题,其中以落叶松、樟子松、和红松等幼苗发病较重,油松和赤松等幼苗发病为轻。幼苗发病征状有土内腐死、猝倒、立枯、地上腐烂、和一、二年生大苗发生枯萎落叶等五个类型。诱致松苗发生侵染性立枯病的病菌,有 Rhizoctonia、Pythium 和 Fusarium等三种菌类,其中 Rhizoctonia 尤为主要。松苗立枯病发生的轻重与育苗措施有密切关系,地势低洼或位于山脚下坡的苗圃或苗床,一般发病较重。种子经雪藏混砂催芽处理后,能提早种子萌芽、出土和齐苗,有降低发病程度的作用。光照多少对幼苗发病有影响。根据苗圃的调查观察,全光育苗发病率低,遮蔭育苗发病率高;但在沈阳试验结果还不能证实这一点,相反的半遮蔭育苗要好些。  相似文献   

The effect of single pretreatment with salbutamol on recovery of bronchoalveolar lavage fluid in horses with suspected or confirmed severe equine asthma     

Mathilde S. Varegg  Kine M. Klverd  Malin K. Austnes  Natalia Siwinska  Malwina Slowikowska  Agnieszka Zak  Artur Niedzwiedz 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(2):976-980

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