承德市第三乡林场不同林分类型枯落物和土壤的持水特性   总被引：6，自引：2，他引：4  

郭宇嘉  牛庆花  陆贵巧  谷建才 《水土保持通报》2018,38(3):38-44

[目的]探究林分枯落物和土壤的水文效应,科学选择持水性能更好的林分类型。[方法]以河北省承德市围场县第三乡林场中落叶松纯林(Ⅰ)、落叶松—白桦—山杨针阔混交林(Ⅱ)、白桦—山杨阔叶混交林(Ⅲ)为研究对象,采用室内浸水法、环刀法以及室内烘干等方法对枯落物和土壤持水特性进行研究。[结果]枯落物总储量:Ⅰ(26.58t/hm2)Ⅱ(25.01t/hm2)Ⅲ(21.55t/hm2)。枯落物最大持水量:Ⅲ(56.88t/hm2)Ⅱ(56.24t/hm2)Ⅰ(51.91t/hm2)。枯落物持水量随浸水时间变化呈对数函数变化趋势。枯落物吸水速率随浸水时间变化呈幂函数变化趋势。枯落物有效拦蓄量:Ⅱ(46.22t/hm2)Ⅲ(43.90t/hm2)Ⅰ(43.36t/hm2)。土壤容重:Ⅰ(1.13g/cm3)Ⅱ(1.12g/cm3)Ⅲ(0.99g/cm3)。土壤总孔隙度:Ⅲ(51.89%)Ⅱ(49.13%)Ⅰ(41.38%)。土壤最大持水量:Ⅲ(1037.80t/hm2)Ⅱ(982.50t/hm2)Ⅰ(827.53t/hm2)。[结论]通过多方面比较3种林分类型枯落物和土壤持水性能,可知Ⅲ持水能力最好,Ⅱ稍弱,Ⅰ最差。  相似文献   

Chimeric mice with humanized liver as a model for testing organophosphate and carbamate pesticide exposure          下载免费PDF全文

Hiroshi Suemizu  Kenji Kawai  Norie Murayama  Masato Nakamura  Hiroshi Yamazaki 《Pest management science》2018,74(6):1424-1430

BACKGROUND

Diagnosis of acute intoxication with organophosphate (OP) or carbamate (CM) pesticides in humans is achieved by measuring plasma butyrylcholinesterase (BuChE) activity. However, BuChE activity is not an ideal biomarker in experimental animal models. The aim of this study was to establish an experimental mouse model for evaluating exposure to OP and CM pesticides by monitoring BuChE activity using chimeric mice in which the liver was reconstituted with human hepatocytes.

RESULTS

A single oral administration of acephate (300 mg/kg), chlorpyrifos (10 mg/kg), fenobucarb (300 mg/kg) or molinate (250 mg/kg) in chimeric mice led to inhibition of >95%, > 95%, 28% and 60% of plasma BuChE activity after 7, 0.5, 0.5 and 7 h, respectively. Dose‐dependent decreases in plasma BuChE activity were also observed for acephate and chlorpyrifos. A 5‐day repeated‐dose study with 10 or 30 mg/kg acephate found a constitutive reduction in plasma BuChE activity to 80% and 70% of pre‐dose levels, respectively.

CONCLUSION

Changes in plasma BuChE activity in chimeric mice with humanized liver clearly reflected the exposure levels of OP and CM pesticides. These results suggest that the humanized‐liver mouse model may be suitable for estimating levels of exposure to these pesticides in humans. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

Genetic relationships among sympatric varieties of <Emphasis Type="Italic">Acer mono</Emphasis> in the Chichibu Mountains and Central Hokkaido,Japan     

Chunping Liu  Jian Cong  Hailong Shen  Cunxue Lin  Yoko Saito  Yuji Ide 《林业研究》2017,28(4):699-704

Acer mono Maxim. is one of the major components of cool temperate forests in Japan. Some of its many varieties are distributed sympatrically. Because of its great variability, the intraspecific taxonomy and nomenclature of the species are controversial. To understand the genetic relationships among these varieties and whether hybridization or introgression occurred among the sympatric varieties, we studied the genetic relationships among sympatric varieties of A. mono in the Chichibu Mountains (A. mono var. ambiguum, A. mono var. connivens, A. mono var. marmoratum) and Central Hokkaido (A. mono var. mayrii and A. mono var. glabrum) in Japan. Our results showed that varieties in Chichibu are genetically close, suggesting that hybridization or introgression might occur between these varieties, which could explain the higher genetic diversity of varieties in Chichibu than in Hokkaido. In contrast to the close relationships between the varieties in Chichibu, varieties in Hokkaido seemed relatively separated from each other; indeed, there may be reproductive isolation between the two varieties. The results provide new insight for the taxonomy of the varieties of A. mono, especially the sympatric varieties, in Japan.  相似文献   

Investigation of acid hydrolysis reactions of polyphosphates and phytic acid in Bray and Mehlich III extracting solutions     

Anthony?P.?Miller  Yuji?AraiEmail author 《Biology and Fertility of Soils》2017,53(7):737-742

Soil test phosphorus (STP) (Bray P-1, Mehlich III) was developed to predict the plant available P in agricultural soils in the USA. The acidic STP extracting solutions were intended to extract phosphate from alkaline earth metal-based solubility products and or adsorbed species on amorphous metal hydroxides or phyllosilicates in soils. However, the accuracy of STP in predicting plant available phosphate has often been questioned due to potential acid hydrolysis of poly- and organic-P in soils during the STP extraction. The objective of the study was to investigate the acid hydrolysis reaction of reference poly- and organic-P compounds (1.25–3.75 mM) in Bray and Mehlich III extraction solutions using spectrophotometric methods. The results showed that both tripolyphosphate and pyrophosphate readily underwent the acid hydrolysis reaction over 2 h, whereas phytic acid did not hydrolyze. The results suggest an overestimation of dissolved reactive phosphate from these polyphosphates should be considered when evaluating the STP data.  相似文献   

A multiplex polymerase chain reaction for discriminating Erysipelothrix rhusiopathiae from Erysipelothrix tonsillarum.   总被引：1，自引：0，他引：1  

Yoshinao Yamazaki 《Journal of veterinary diagnostic investigation》2006,18(4):384-387

Erysipelothrix rhusiopathiae is the causative agent of swine erysipelas, and it causes great economic losses in Japan and worldwide. In meat inspection, it is very important to distinguish E. rhusiopathiae from other bacteria showing similar clinical signs of disease or similar bacterial characteristics. To distinguish E. rhusiopathiae from Erysipelothrix tonsillarum, 2 polymerase chain reaction (PCR) systems were combined. The primer sets ERY-1F and ERY-2R were designed to amplify 2210 base pairs (bp) of nucleotide sequence specific for E. rhusiopathiae chromosomal DNA, and the primer sets MO101 and ERS-1R were designed to amplify 719 bp of nucleotide sequence including a highly conserved region of genus Erysipelothrix 16S rRNA. Two fragments were amplified when E. rhusiopathiae was used as the PCR template using the primer sets, whereas a single fragment was amplified when E. tonsillarum was used as the template. No fragments were amplified when nucleic acid from other bacteria that cause clinical signs similar to swine erysipelas were used as the template. Moreover, 5 specimens collected from postinspected swine carcasses were diagnosed as E. rhusiopathiae using the PCR described in this study, in agreement with results of microbiological tests for the genus Erysipelothrix, whereas negative samples were negative both in conventional bacterial tests and by PCR. The detection limit of multiplex PCR ranged from 10(2) to 10(4) colony forming units per reaction tube for positive samples. These results suggest that this method is useful for screening of swine erysipelas in meat inspection centers.  相似文献   

实蝇科昆虫对寄主植物的选择和响应研究进展          下载免费PDF全文

郭腾达  秦誉嘉  李志红 《植物保护》2023,49(5):196-206

实蝇科昆虫种类繁多, 全球广泛分布, 其中诸多种类可直接为害果蔬, 造成巨大经济损失, 是国际检疫性或入侵性害虫。实蝇主要通过成虫产卵和幼虫取食来为害寄主植物, 实蝇与寄主植物之间的相互作用包括实蝇对寄主的选择以及实蝇对寄主的响应。本文综述了实蝇科昆虫对寄主植物的选择, 包括对不同寄主植物种类、寄主植物不同部位和寄主植物不同品种的选择; 以及对寄主植物的响应包括对寄主植物的生长发育响应, 对寄主植物的行为响应。同时总结了实蝇的化学感受器官、化学感受基因及抗性相关基因在实蝇对寄主植物选择和响应中的作用, 以期为深入了解实蝇科昆虫对寄主植物的选择和响应机制以及研发实蝇类害虫防治技术提供参考。  相似文献   

浙贝母灰霉病病原真菌的分子鉴定     

李吉二  温思思  张羽加  金洛稼  赵伟春 《植物保护》2022,48(2):151-156

为了鉴定引起浙贝母Fritillaria thunbergii Miq.灰霉病的病原真菌,于2015年-2019年收集浙贝母灰霉病样品,采用常规组织分离法在PDA培养基上分离纯化获得10株葡萄孢属Botrytis真菌.进一步以内转录间隔区(internal transcribed spacer,ITS)、RNA 聚合酶...  相似文献   

不同秸秆还田方式对旱地红壤细菌多样性及群落结构的影响   总被引：3，自引：0，他引：3  

栾璐  郑洁  程梦华  胡凯婕  孔培君  蒋瑀霁  孙波 《土壤》2021,53(5):991-997

为明确不同秸秆还田方式下土壤细菌群落结构变化特征，以南方典型旱地红壤为研究对象，基于中国科学院鹰潭红壤生态实验站玉米单作系统不同秸秆还田方式的长期试验，利用高通量测序明确了不同秸秆还田方式对土壤细菌多样性及群落结构的影响。结果表明：1）秸秆还田对土壤肥力提升显著，以秸秆猪粪配施（NPKSM）提升效果最佳；2）常规化肥处理（NPK）对细菌多样性无显著影响，但秸秆还田（NPKS）、秸秆猪粪配施（NPKSM）以及生物质炭（NPKB）处理均显著提升土壤细菌多样性；3）速效磷（AP）和土壤有机碳（SOC）变化是影响细菌多样性指数的主要因素，而速效钾（AK）、pH、总磷（TP）以及总氮（TN）均显著驱动细菌群落结构变异。研究结果从培育红壤肥力与微生物多样性的角度，为农业生态系统生物功能和土壤健康的协同提升提供了科学依据。  相似文献   

基于@RISK软件评估玉米根萤叶甲对我国玉米产业造成的潜在经济损失          下载免费PDF全文

魏鹏  秦誉嘉  王振营  赵守歧  李志红 《植物保护学报》2022,49(5):1411-1416

为评估玉米根萤叶甲 Diabrotica virgifera virgifera对我国玉米产业的潜在经济损失，在收集整理玉米产量、种植面积、市场价格以及玉米根萤叶甲为害和防控相关数据的基础上，结合其在我国的潜在地理分布，构建不防控和防控2种场景下玉米根萤叶甲的潜在经济损失随机模型，并利用@RISK软件预测其可能给我国玉米产业带来的潜在经济损失。结果显示，在不防控和防控场景下，玉米根萤叶甲对我国玉米产业造成的潜在经济损失总量分别为187.35亿~273.65亿元（90%置信区间）和47.31亿~102.65亿元（90%置信区间）；而在投入防控措施后，可挽回的潜在经济损失介于104.87亿~205.37亿元（90%置信区间）之间。表明玉米根萤叶甲可对我国玉米产业造成严重的潜在经济损失，采取积极的防控措施严防该害虫入侵我国是十分必要的。  相似文献   

沙漠蝗在中国的潜在地理分布     

张源  秦誉嘉  赵紫华  涂雄兵  张泽华  李志红 《植物保护学报》2021,48(1):90-95

为明确世界性害虫沙漠蝗Schistocerca gregaria入侵我国的风险性,根据沙漠蝗已知的全球最新分布数据,利用MaxEnt模型结合ArcGIS软件对其在我国的潜在地理分布进行预测,并对19个相关环境因子的贡献率进行分析.结果 显示:陕西、宁夏、西藏、云南、新疆、青海、甘肃、河北、河南、山东、内蒙古、山西、四川...  相似文献