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Analysis on the Climatic Characteristics of Hail in the South Mountain Area of Ningxia 被引量:2
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作者 RAO Tong-hua CHEN Hai-bo ZHANG Cheng-jun 《Meteorological and Environmental Research》 CAS 2011年第2期33-35,39,共4页
[Objective] The research aimed to study the climatic characteristics of hail in the southern mountain area of Ningxia in recent 50 years. [Method] Based on the hail observation data of 5 surface meteorological station... [Objective] The research aimed to study the climatic characteristics of hail in the southern mountain area of Ningxia in recent 50 years. [Method] Based on the hail observation data of 5 surface meteorological stations (Guyuan, Xiji, Jingyuan, Longde, Liupanshan) in the south of Ningxia during 1960-2009, the spatial distribution rule, the interannual and monthly climatic characteristics and variation trends of hail in the south mountain area of Ningxia were analyzed by using the statistical method. Moreover, the hail disaster prevention and reduction measures in Guyuan were put forward. [Result] The hail in the south mountain area of Ningxia in recent 50 years had the obvious annual, seasonal, monthly and daily variation characteristics. The hail might occur from March to October and mainly concentrated during May-August which occupied 72% in the whole year. The occurrence probability of hail in June was the biggest and occupied 21.7% in the whole year. It was the typical multi-hail zone in summer. The interannual variation of hail occurrence in Guyuan was big and had 3-year periodicity. The secondary-order time trend of hail in Guyuan was the anti-parabolic type, and the hail occurrence times during the 1960s-1980s presented the increase trend. It was the hail multi-occurrence period in the 1970s and 1980s. After the 1990s, the hail presented the decrease trend. In recent 20 years, the hail significantly decreased. The hail in Guyuan mainly concentrated during 12:00-21:00, and the hail occurrence times occupied 85% of total times. The hail distribution in Guyuan area had the obvious regional characteristics. The hail in the mountain area, hilly area was more and in the stream valley, north Pingchuan area was less. The hail cloud mainly derived from the mountain areas, such as Liupanshan, Nanhua Mountain, Yueliang Mountain, Xifeng Mountain and Yunwu Mountain, etc. The move direction of hail cloud was mainly from northwest to southeast or from north to south. Part of hail cloud disappeared in the original place. According to the regional distribution of hail, the hail risk in Guyuan City was divided into the high, moderate and low occurrence zones by combining with the hail disaster data. [Conclusion] The research provided the scientific basis for the forecast, early-warning of hail weather and the artificial hail suppression. 展开更多
关键词 HAIL Climatic characteristics Variation trend South mountain area of ningxia China
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Study on the Countermeasures of Eco-environment Conservation in the Mountainous Areas of Southern Ningxia under New Situation 被引量:1
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作者 JIA Yao-feng School of Management,North China University of Nationalities,Yinchuan 750021,China 《Meteorological and Environmental Research》 CAS 2011年第3期53-56,72,共5页
Under the implementation of principal functional zoning,further promotion of western development,regional migration,new countryside construction,global warming and so on,the spatial adjustment of regional industry and... Under the implementation of principal functional zoning,further promotion of western development,regional migration,new countryside construction,global warming and so on,the spatial adjustment of regional industry and its structure must be enforced.The spatial adjustment and arrangement of population and economy in the mountainous areas of southern Ningxia could create tremendous opportunity for its eco-environment conservation.Based on analysis on the opportunity and challenge of eco-environment conservation in the mountainous areas of southern Ningxia,some countermeasures of eco-environment conservation were discussed in the paper,so as to provide some theoretical references for the eco-environment conservation in the mountainous areas of southern Ningxia. 展开更多
关键词 Mountainous areas of southern ningxia New situation Eco-environment conservation COUNTERMEASURE China
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Analysis of the Ecological Migration Pattern in Ethnic Minority Areas——A Case Study of Ningxia Hui Autonomous Region 被引量:4
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作者 ZHANG Yun-yan School of Politics and Law,Ningxia University,Yinchuan 750021,China 《Asian Agricultural Research》 2011年第8期85-89,共5页
By taking Ningxia Hui Autonomous Region as an example,this paper analyzes the ecological migration pattern in ethnic minority areas.The basic patterns of development for poverty relief in Ningxia are in-situ migration... By taking Ningxia Hui Autonomous Region as an example,this paper analyzes the ecological migration pattern in ethnic minority areas.The basic patterns of development for poverty relief in Ningxia are in-situ migration and new area development pattern.The new area development pattern includes three types,namely small town development pattern around urban radiation districts,urban labor migration pattern,and large-scale ecological migration pattern.Finally,successful experience of ecological migration in Ningxia is summarized.First,scientific industrial planning shall be made on the basis of proper selection of ecological migration location in immigrant settlement regions.Second,scientific and comprehensive ecological migration policies should be formulated. 展开更多
关键词 ETHNIC MINORITY areas ECOLOGICAL MIGRATION PATTERN
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THE RATIONAL UTILIZATION OF WATER RESOURCES IN IRRIGATED AREA OF THE YELLOW RIVER IN NINGXIA
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作者 Liu Baizhang Fang Wanjun Working Office of First Phase Daliushu Project, Department of Water Conservancy of Ningxia,China Division of Management of Tanglai Canal, Department of Water Conservancy of Ningxia, China 《干旱区资源与环境》 CSCD 1993年第Z1期192-196,共5页
The paper describes the water resources in the irrigated area of Ningxia, China, andthe methods for improving the utilization of the water resources, and puts forward somesuggestions so as to utilize the water resourc... The paper describes the water resources in the irrigated area of Ningxia, China, andthe methods for improving the utilization of the water resources, and puts forward somesuggestions so as to utilize the water resources rationally. The history of irrigation farming in Ningxia can be traced back to more than two thou- 展开更多
关键词 ningxia IRRIGATED area by YELLOW RIVER Water RESOURCES Ecologic ENVIRONMENT
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RECENT TECTONIC DEFORMATION ANOMALY AND EARTHQUAKES IN GANSU-NINGXIA-QINGHAI AREA
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作者 Wang Shuangxu, Zhang Xi, Zhang Sixin and Xue Fuping (Second Crust Monitoring and Application Center, CEA, Xi’an 710054 China) 《大地测量与地球动力学》 CSCD 2003年第B12期94-100,共7页
By processing and analyzing geodetic data of vertical deformation, fault deformation and horizontal deformation by GPS in Gansu Ningxia Qinghai area and by comparing them with geological structures and many medium to ... By processing and analyzing geodetic data of vertical deformation, fault deformation and horizontal deformation by GPS in Gansu Ningxia Qinghai area and by comparing them with geological structures and many medium to strong earthquake activities in this area, some features of recent tectonic deformation anomaly and the development of medium to strong earthquakes are studied. The results show that: ①Near the main faults tectonic deformations are relatively large. The amount of vertical movement and the deformation status evolve with time. The horizontal movement and deformation show obvious compressional strike slip character. ②The dominant stress of tectonic deformation and seismic development in this area comes from the persistent northeastward compression of Qinghai Tibet block;The time spatial distribution evolution of tectonic deformation and seismic activities are closely related to dynamic evolution of block motion and regional tectonic stress field. ③The abnormal uplift and high gradient deformation belts and remarkable fault deformation anormaly on the borders of regional tectonic blocks are indicators of developing moderate to strong earthquakes but earthquakes may not necessarily take place in the position of maxium deformation, it usually occurred in the region where fault deformation anormaly shows “trend accumulation acceleration turn ” variation character or nearby. On the basis of above study, a preliminary prediction for strong earthquake risk in this area is given. 展开更多
关键词 甘肃-宁夏-青海地区 纵向变形场 横向变形发展 断层活动异常 地震预报 区域数据处理
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AN APPROACH TO THE FORESTRY PROBLEMS AND TACTS IN THE NEW IRRIGATION AREA OF YANGHUANG IN NINGXIA
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作者 Jiang Qi Xu Rong Forestry Institue of NingXia Agricutural and Forestry Academy 《干旱区资源与环境》 CSCD 1993年第Z1期355-357,共3页
This article exponded the importance of forestry construction in Ningxia, Yang HuangNew Irrigation Area economy development. It analysed the problems that may exist in theforestry constructions of New Irrigation Area,... This article exponded the importance of forestry construction in Ningxia, Yang HuangNew Irrigation Area economy development. It analysed the problems that may exist in theforestry constructions of New Irrigation Area, (such as the monostructure of trees,struction simplicity, monoculture of stand and lack of functions) And put forward the cont-er actions and construtioes advices. 展开更多
关键词 ningxia YangHuang New IRRIGATION area FORESTRY Ecoeconomic PATTERN
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Rayleigh Wave Tomography of Ningxia and Its Adjacent Areas Based on Ambient Noise
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作者 Xie Hui Ma Heqing +3 位作者 Ma Xiaojun Li Qingmei Zhang Nan Ren Jiaqi 《Earthquake Research in China》 CSCD 2016年第4期542-555,共14页
In this article,the vertical components of the continuous waveform data of 90 seismic stations in Ningxia and its adjacent regions recorded from January 2012 to December 2013 are used to obtain the Rayleigh surface wa... In this article,the vertical components of the continuous waveform data of 90 seismic stations in Ningxia and its adjacent regions recorded from January 2012 to December 2013 are used to obtain the Rayleigh surface wave group velocity dispersion images in the study area( 101°- 112°E,31°-42°N) according to the method of noise imaging,with period between 6s - 50s and resolution of 0.5°. The Yinchuan basin in the 6s - 26 s period obviously shows a low velocity anomaly,which is not uniform and has a tendency to gradually weaken; the Guanzhong Basin in 6 s-22s shows a strip of low velocity anomaly and demonstrates a transverse inhomogeneity,where velocity in the southeast is slightly faster than that in the northwest. In the 30s - 50s period it shows that in the Yinchuan graben basin and its southern area,there is a large low velocity anomaly area,which moves from northeast to southwest. It shows that between the main active tectonic zones,like mountains and basins,there are obvious geomorphologic boundaries. For example,the deep fault near Liupan Mountain is the dividing line between two large tectonic units of eastern and western of China. The inversion results have good correlation with the geological structure and the stratigraphic landform. The results are consistent with the results of artificial seismic section tomography across the basin. It provides an important basis for the dynamics of active tectonic zones and the mechanism of earthquake occurrence in this area. 展开更多
关键词 层析成像 环境噪声 宁夏 瑞利波 群速度色散 横向不均匀 活动构造带 银川盆地
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The Models for the Development of Specialty Agriculture in the Hilly Areas of Southern Ningxia: Are They Truly Effective?
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作者 Xiaoyi SUN Qing TANG +1 位作者 Yong XU Lijuan DANG 《Asian Agricultural Research》 2013年第10期35-38,42,共5页
The development of specialty agriculture is of great significance to western China's agricultural structure adjustment,and it's an essential way for the construction of ecological agriculture in Southern Ningx... The development of specialty agriculture is of great significance to western China's agricultural structure adjustment,and it's an essential way for the construction of ecological agriculture in Southern Ningxia mountainous area.This paper makes a summary about the development status of specialty agriculture in Southern Ningxia Mountainous Area and put forward the basic benefit goal and problems needing attention.On this basis,the paper studies the development pattern of specialty agriculture in Southern Ningxia Mountainous Area from the aspects of production factors and industry.This paper suggests that the development pattern of specialty agriculture in Southern Ningxia Mountainous Area should combine the regional agricultural pattern and innovative organization structure pattern,demonstration agriculture and market-directing pattern,engineering agricultural pattern and enterprise-driven pattern.The development of specialty agriculture in Southern Ningxia Mountainous Area should promote the three patterns,in order to achieve the construction of ecological agriculture and agricultural structure adjustment. 展开更多
关键词 The HILLY areas of SOUTHERN ningxia SPECIALTY agri
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气候变化背景下宁夏灌区冻土变化特征及其对农业生产的影响
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作者 杨洋 贾彪 李阳 《宁夏农林科技》 2024年第2期22-31,共10页
为掌握气候背景下宁夏灌区季节性冻土变化及其对农事活动的影响,争取最大限度地提高光热资源利用效率,挖掘生产潜力,开展了气候变化背景下宁夏灌区冻土变化特征及其对农业生产的影响研究。利用宁夏灌区4个代表性站点1961—2020年冬季逐... 为掌握气候背景下宁夏灌区季节性冻土变化及其对农事活动的影响,争取最大限度地提高光热资源利用效率,挖掘生产潜力,开展了气候变化背景下宁夏灌区冻土变化特征及其对农业生产的影响研究。利用宁夏灌区4个代表性站点1961—2020年冬季逐日冻土资料,采用统计方法,分析宁夏灌区逐年最大冻土深度、土壤冻结日期、解冻日期及冻结日数变化特征,并分析冻土变化对农业生产的影响。结果表明,1961—2020年冬季各代表性站点中最大冻土深度均有明显的变化趋势,2001年以前各地最大冻土深度明显变浅,2001年以后惠农、永宁、吴忠整体冻土深度有所增加,永宁、吴忠呈波动性变化,无明显趋势性变化;1961—2020年中宁最大冻土深度明显变浅。土壤冻结日期、完全解冻日期分别有不同程度延后和提前趋势;各站点冻土持续日数年变化呈缩短的趋势,其中中宁的冻土持续时间缩短趋势最明显。 展开更多
关键词 宁夏灌区 土壤冻结 冻土深度
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供钾水平对宁南山区花椰菜产量及钾素平衡的影响
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作者 冯海萍 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第3期165-172,共8页
【目的】为宁夏冷凉花椰菜生产中钾肥合理施用提供科学依据。【方法】以宁夏冷凉主导花椰菜为试验材料,设置0(K_(0))、10(K_(10))、20(K_(20))、30(K_(30))、40 kg/667m^(2)(K_(40))5个施钾水平,通过田间试验,研究供钾对露地花椰菜产量... 【目的】为宁夏冷凉花椰菜生产中钾肥合理施用提供科学依据。【方法】以宁夏冷凉主导花椰菜为试验材料,设置0(K_(0))、10(K_(10))、20(K_(20))、30(K_(30))、40 kg/667m^(2)(K_(40))5个施钾水平,通过田间试验,研究供钾对露地花椰菜产量、钾素吸收分配利用及土壤根层钾素质量与平衡的影响。【结果】供钾显著增加花椰菜产量,增产率在5.32%~16.24%,供钾水平与花球产量呈极显著的二次抛物曲线关系,最高产量为3 529.43 kg/667 m^(2),最佳供钾水平为24.28 kg/667 m^(2)。在苗期和莲座期茎叶是花椰菜钾元素的累积中心,不同处理茎叶分配比例在49.67%~90.49%,进入成熟期花球是花椰菜钾元素的累积中心,不同处理花球累积分配比例在42.25%~53.73%,整株花椰菜钾素累积量苗期以K_(30)处理最高,莲座期和成熟期均以K_(20)处理最高,较对照分别显著提高69.40%、79.38%。钾肥利用效率为21.77%~40.31%,以K20处理的钾肥利用率、贡献率及农学效率均最高,分别为45.28%,21.31%、38.670 kg/kg。供钾水平低于20 kg/667 m^(2)时,土壤钾素平衡表现为亏缺,供钾水平超过30 kg/667 m^(2)钾素盈余由负转正,再继续投入钾肥,钾素盈余。【结论】综合考虑花椰菜钾素吸收利用分配与产量和土壤钾素有效性与菜田钾素收支平衡等因素,建议宁夏南部山区花椰菜适宜的供钾水平为21.82~29.24 kg/667 m^(2)。 展开更多
关键词 花椰菜 宁夏南部山区 供钾水平 产量 钾肥利用率 钾素平衡
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宁夏中部干旱区露地甘薯栽培适应性比较研究
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作者 张丽娟 曲继松 +3 位作者 朱倩楠 黄灵丹 杜海东 王瑞 《宁夏农林科技》 2024年第4期5-12,共8页
为丰富宁夏干旱区适宜栽种的甘薯品种,实现区域甘薯产业高质高效持续发展,以收集的国内外23个甘薯品种为材料,对植株农艺性状、甘薯产量、甘薯品质、栽培适应性等多指标进行比较分析。结果表明,徐薯25、苏薯8号、安平一号、济薯26号、徐... 为丰富宁夏干旱区适宜栽种的甘薯品种,实现区域甘薯产业高质高效持续发展,以收集的国内外23个甘薯品种为材料,对植株农艺性状、甘薯产量、甘薯品质、栽培适应性等多指标进行比较分析。结果表明,徐薯25、苏薯8号、安平一号、济薯26号、徐薯55-1、安纳芋、徐薯27、岩薯5号8个品种为早熟品种,9月中旬为最佳采收期。徐薯28和烟薯25号2个品种9月中旬至10月初采收均可;其他品种为中晚熟品种,适宜10月初采收。烟薯25号、川薯产量高(单株产量分别为2518 g、2295 g),综合品质较好。济薯26号和徐薯55-2产量及可溶性糖含量(分别为3.32%和3.25%)、富硒方面均有优势,适宜开发本地区鲜食品种;徐紫8号、徐紫5号2个紫薯品种产量均不高;徐紫8号粗纤维含量低,硒含量较高;徐紫5号淀粉含量较高。烟薯25号、川薯、济薯26号和徐薯55-2可作为宁夏干旱区域甘薯推荐种植品种。 展开更多
关键词 甘薯 露地栽培 农艺性状 适应性 宁夏中部干旱区
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微生物菌剂对连作芹菜根际土壤真菌群落多样性与结构的影响
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作者 冯海萍 陈卓 杨虎 《干旱地区农业研究》 CSCD 北大核心 2024年第2期53-61,70,共10页
以宁南旱区连作4年芹菜根际土壤为研究对象,采用田间定位试验结合高通量测序技术,以常规施肥(CK)为对照,研究常规施肥+枯草·哈茨复合菌剂(MF),常规施肥+枯草芽孢杆菌(BS),常规施肥+哈茨木霉菌(TH)3个处理对芹菜连作根际土壤真菌多... 以宁南旱区连作4年芹菜根际土壤为研究对象,采用田间定位试验结合高通量测序技术,以常规施肥(CK)为对照,研究常规施肥+枯草·哈茨复合菌剂(MF),常规施肥+枯草芽孢杆菌(BS),常规施肥+哈茨木霉菌(TH)3个处理对芹菜连作根际土壤真菌多样性及群落组成的影响。结果表明:施用枯草·哈茨复合菌显著提高了土壤有效磷、速效钾含量,增幅分别为34.29%和9.98%。施用微生物菌剂增加了土壤脲酶、蔗糖酶活性,平均增幅分别为43.16%和12.98%,并显著改变了土壤真菌的β-多样性。被孢霉属(Mortierella)、织球壳属(Plectosphaerella)、赤霉菌属(Gibberella)、链格孢属(Alternaria)、镰刀菌属(Fusarium)是各处理优势菌属,施用枯草·哈茨复合菌显著降低了赤霉菌属、链格孢属、镰刀霉属等真菌性病原菌的相对丰度,降幅分别为59.88%、51.63%、36.13%。冗余分析表明土壤蔗糖酶、脲酶、碱性磷酸酶活性、pH值和全磷是影响真菌群落结构组成的主要驱动因子。综合而言,枯草·哈茨复合菌剂的施用不仅降低了连作芹菜根际土壤镰刀菌属、链格孢属、赤霉菌属等病原菌的富集,还通过改变有效磷、速效钾等土壤理化性质,进一步重塑土壤真菌群落结构。 展开更多
关键词 芹菜 连作 微生物菌剂 土壤理化性质 真菌群落结构 宁南山区
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苜蓿蓟马空间动态与作物布局关系研究
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作者 朱猛蒙 孙玉荣 +2 位作者 陈林 陈彦虎 马俊贵 《宁夏农林科技》 2024年第3期30-35,共6页
【目的】明确宁夏南部山区苜蓿蓟马空间种群动态与作物环境布局之间的关系。【方法】利用高空遥感无人机获取宁夏南部山区4个研究区域的遥感图片,经处理后计算其景观格局指数,明确景观与蓟马种群动态之间的关系。【结果】离散核心区数量... 【目的】明确宁夏南部山区苜蓿蓟马空间种群动态与作物环境布局之间的关系。【方法】利用高空遥感无人机获取宁夏南部山区4个研究区域的遥感图片,经处理后计算其景观格局指数,明确景观与蓟马种群动态之间的关系。【结果】离散核心区数量(NDCA)、总边界长(TE)、总面积比(CA/TA)、核心区面积均值(Core_MN)、斑块丰度密度(PRD)与蓟马发生量相关,相关系数为-0.99~0.97。【结论】南部山区在梯田、台塬上种植苜蓿,对于蓟马控制具有地形优势;蓟马在跨越高低起伏的地形上,必须依靠一定的气象条件才能顺利转移;但生境破碎化,容易造成蓟马爆发成灾。 展开更多
关键词 景观 苜蓿蓟马 空间动态 宁夏南部山区
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百年中国法治历史中的陕西党史元素
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作者 韩伟 《榆林学院学报》 2024年第4期72-76,共5页
中国特色社会主义法治模式,是百年来中国共产党领导法治的探索成果,是从革命时期局部执政到当代中国治国理政法治经验的总结。党领导法治的历史,特别是中共中央在延安的十三年,蕴含着丰富的陕西党史元素,不仅体现在局部执政的法治建设... 中国特色社会主义法治模式,是百年来中国共产党领导法治的探索成果,是从革命时期局部执政到当代中国治国理政法治经验的总结。党领导法治的历史,特别是中共中央在延安的十三年,蕴含着丰富的陕西党史元素,不仅体现在局部执政的法治建设、依规治党的经验,还体现为陕西党史中的红色法制历程。总结和凝练党领导法治历史中的陕西元素,有助于理解当代中国的法治,拓展陕西党史的研究。 展开更多
关键词 全面依法治国 党史 陕甘宁边区 根据地法律史
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宁夏地区牛乳肠球菌耐药性分析
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作者 乔亚蕊 杨江流 +2 位作者 高登军 付娜娜 周学章 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2024年第8期1-10,共10页
【目的】了解宁夏地区奶牛正常乳汁和患乳腺炎乳汁中肠球菌的分布规律及其耐药特征,为宁夏地区奶牛乳腺炎疾病的抗菌药物合理使用提供参考。【方法】对宁夏地区16个规模化奶牛养殖场近3年来1154份乳汁样品(正常乳汁383份,患乳腺炎乳汁77... 【目的】了解宁夏地区奶牛正常乳汁和患乳腺炎乳汁中肠球菌的分布规律及其耐药特征,为宁夏地区奶牛乳腺炎疾病的抗菌药物合理使用提供参考。【方法】对宁夏地区16个规模化奶牛养殖场近3年来1154份乳汁样品(正常乳汁383份,患乳腺炎乳汁771份)进行肠球菌分离,采用形态学观察和生化试验对分离所获的496株肠球菌进行鉴定,通过K-B药敏纸片扩散法测定分离肠球菌菌株对青霉素(PG)、头孢唑林(CFZ)、庆大霉素(GEN)、四环素(TET)、红霉素(EM)、林可霉素(LCM)、链霉素(SM)和万古霉素(VCA)等8种药物的敏感性,并使用PCR方法对分离肠球菌菌株进行四环素类药物耐药基因(tetA、tetB、tetC、tetM)、大环内酯类药物耐药基因(mecA、ermA、ermB、ermC)以及林可胺类药物耐药基因(lsaA、lsaE、lnuG、lnuA)检测。【结果】从1154份乳样中共分离得到496株肠球菌,经鉴定分属6种肠球菌,分别是屎肠球菌、海氏肠球菌、粪肠球菌、蒙氏肠球菌、耐久肠球菌和鹑鸡肠球菌。其中屎肠球菌305株,占分离菌株总数的61.5%;海氏肠球菌124株,占分离菌株总数的25.0%;粪肠球菌27株,占分离菌株总数的5.4%;蒙氏肠球菌21株,占分离菌株总数的4.2%;耐久肠球菌15株,占分离菌株总数的3.0%;鹑鸡肠球菌4株,占分离菌株总数的0.8%。临床分离菌株对林可霉素、四环素、红霉素的耐药率分别达到95.8%,82.7%和80.2%,尤以耐7种药物的菌株为主,达230株(占耐药菌株的46.4%),最常见的耐药谱为PG+CFZ+GEN+TET+EM+LCM+SM。正常乳汁中分离的菌株主要为海氏肠球菌(检出率为73.8%),对林可霉素的耐药率最高(94.5%);患乳腺炎乳汁中分离的菌株主要为屎肠球菌(检出率为89.5%),对四环素的耐药率最高(97.0%)。496株临床肠球菌中有488株检测出携带耐药基因,检出率为98.4%;检测出乳源肠球菌不携带tetA、tetB、tetC、mecA、lnuG和lnuA耐药基因;携带ermA、ermB、ermC、tetM、lsaA和lsaE耐药基因,其携带率分别为51.0%,80.3%,33.2%,88.1%,41.6%和74.4%;最常见耐药基因谱为ermA+ermB+tetM+lsaE+lsaA。【结论】宁夏地区奶牛乳汁中肠球菌耐药性严重,且具有多重耐药性特征,给公共卫生带来潜在危害,应引起高度重视。 展开更多
关键词 肠球菌 奶牛乳汁 耐药性分析 耐药基因 宁夏地区
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宁夏东部杨柴生态修复区短期水氮添加对草本植物群落的影响
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作者 苗虎 邱开阳 +7 位作者 苏云 刘王锁 何毅 赵香君 李海泉 黄业芸 李亚园 谢应忠 《生态科学》 CSCD 北大核心 2024年第2期202-210,共9页
为研究短期水氮添加对杨柴生态修复区草本植物群落数量特征及其多样性的影响,在宁夏白芨滩国家级自然保护区杨柴生态修复区进行水氮添加试验,采用随机区组设计试验,每个区组设置4个水添加梯度(W0:未添加水分;W1:添加多年平均降水量的33%... 为研究短期水氮添加对杨柴生态修复区草本植物群落数量特征及其多样性的影响,在宁夏白芨滩国家级自然保护区杨柴生态修复区进行水氮添加试验,采用随机区组设计试验,每个区组设置4个水添加梯度(W0:未添加水分;W1:添加多年平均降水量的33%;W2:添加多年平均降水量的66%;W3:添加多年平均降水量的100%)和4个氮添加梯度(氮添加量分别为N0:未添加氮素;N1:5 g·m^(-2)·a^(-1);N2:10 g·m^(-2)·a^(-1);N3:20 g·m^(-2)·a^(-1))两两随机组合的16个水氮添加处理,共4个区组。结果表明:(1)不同水氮添加使植物群落结构发生了显著变化,与对照(W0N0)相比,草本层优势种狗尾草的重要值在中氮不施水(W0N2)、低水耦合高氮(W1N3)、中水不施氮(W2N0)、中水耦合中氮(W2N2)几种处理下达到最大值,其峰值为0.46,狗尾草集群分布明显,表明在中度水平的单一水、氮或中度水平的水氮耦合措施下群落聚集效应明显。(2)在不同水氮添加处理下,从不施氮(N0)到高氮水平(N3),草本植物群落物种丰富度、Shannon-Wiener多样性指数、Simpson优势度指数以及Pielou均匀度指数均随着氮水平的增加呈先增大后减小的趋势,且都在中水耦合低氮(W2N1)处理下有最大值。(3)氮添加对于生态修复区植物的物种丰富度、Simpson优势度指数以及Shannon-Wiener多样性指数均有显著影响(P<0.05)。综上,适量的水和氮添加更有利于生态修复区植被恢复,W2N1处理能够最好地改善杨柴生态修复区草本层植物群落物种多样性,从而有效地促进了沙漠化逆转进程。 展开更多
关键词 水分添加 氮添加 杨柴 生态修复区 宁夏 数量特征 群落结构 植物多样性
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引黄灌区连续减施化肥对春小麦产量稳定性的影响
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作者 王月梅 田海梅 +5 位作者 王西娜 郝雯悦 吕喆铭 于金铭 谭军利 王朝辉 《中国农业科学》 CAS CSCD 北大核心 2024年第3期539-554,共16页
【目的】探索宁夏引黄灌区连续减施化肥对土壤氮、磷、钾养分供应及春小麦产量的影响,并分析影响产量稳定性的因素,为化肥合理减施、春小麦高产稳产提供理论依据。【方法】以宁春4号春小麦为供试作物,2019-2022年连续4年开展化肥减施田... 【目的】探索宁夏引黄灌区连续减施化肥对土壤氮、磷、钾养分供应及春小麦产量的影响,并分析影响产量稳定性的因素,为化肥合理减施、春小麦高产稳产提供理论依据。【方法】以宁春4号春小麦为供试作物,2019-2022年连续4年开展化肥减施田间定位试验,试验设置常规施肥(CF,N 270 kg·hm^(-2)、P_(2)O_(5)150 kg·hm^(-2)、K_(2)O 75 kg·hm^(-2))、减量施肥下限(RF1,N 180 kg·hm^(-2)、P_(2)O_(5)45 kg·hm^(-2)、K_(2)O 30 kg·hm^(-2),与传统施肥相比减N 33.3%、减P_(2)O_(5)70.0%、减K_(2)O 60.0%)、减量施肥上限(RF2,N 225 kg·hm^(-2)、P_(2)O_(5)75 kg·hm^(-2)、K_(2)O 45 kg·hm^(-2),与传统施肥相比减N 17.0%、减P_(2)O_(5)50.0%、减K_(2)O 40.0%)及不施肥(CK)处理,分析春小麦生育期间气候因素,播前土壤水分含量,播前和收获期土壤矿质态氮、速效磷、速效钾含量,收获期春小麦地上部干物质累积量、籽粒产量及产量构成因素的差异及相互关系。【结果】2019-2022年播前土壤水分含量存在年际差异,其中2022年的较低,平均值仅为19.5%;除2020年受施肥处理显著影响外,其余年份各施肥处理之间无显著差异。播前和收获期土壤矿质态氮、速效钾和速效磷含量均以常规施肥(CF)处理较高,RF2处理次之,且两者之间无显著差异,而RF1处理的趋于降低。2019年,地上部干物质累积量和产量均以CF处理最高,分别为23261.7和9449.0 kg·hm^(-2),较RF2处理增幅分别为2.8%-4.5%和3.2%-16.0%,而2020-2022年均以RF2处理较高,但与CF处理之间无显著差异,且4年籽粒产量表现最稳定;从年际变化来看,所有施肥处理的公顷穗数、千粒重、产量均呈逐年下降的趋势,因此施肥量并不是造成产量年际差异的主要原因,而是与播前土壤水分、降水量、气温、湿度和风速有密切关系,其中2022年产量的降低主要与较低的播前土壤水分、灌浆期的干热风现象及氮肥基追比的改变有关。【结论】宁夏引黄灌区连续适量减施化肥(N225 kg·hm^(-2)、P_(2)O_(5)75 kg·hm^(-2)、K_(2)O 45 kg·hm^(-2),相对常规施肥减N 17.0%,减P_(2)O_(5)50.0%,减K_(2)O 40.0%)不会显著降低土壤氮、磷、钾的供应能力,且一定程度上提高了春小麦公顷穗数、穗粒数和千粒重,促进地上部干物质量向籽粒的转移和积累,从而趋于提高春小麦的籽粒产量。但是,春小麦产量受降雨、风速、湿度等气候因素和土壤墒情、连作障碍、氮肥追施比等的影响而存在年际差异,其中,气温、相对湿度和风速是影响小麦产量差异的主要因素,其对施肥效果的影响需做进一步研究。 展开更多
关键词 春小麦 连续减施化肥 土壤速效养分 干物质量 产量稳定性 宁夏引黄灌区
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宁夏扬水灌区灌溉水利用系数驱动机制及调控方法研究
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作者 席睿 姬小敏 +1 位作者 黑正军 唐莲 《宁夏工程技术》 CAS 2024年第2期132-138,共7页
基于2015—2019年宁夏红寺堡、固海、固扩、盐环定扬水灌区的相关数据,借助改进的STIRPAT模型对4个扬水灌区的灌溉水利用系数进行了研究,分析了人为影响因素对灌区灌溉水利用系数产生的影响,并且对人为因素和气候因素综合影响下的灌溉... 基于2015—2019年宁夏红寺堡、固海、固扩、盐环定扬水灌区的相关数据,借助改进的STIRPAT模型对4个扬水灌区的灌溉水利用系数进行了研究,分析了人为影响因素对灌区灌溉水利用系数产生的影响,并且对人为因素和气候因素综合影响下的灌溉水利用系数变化规律进行了预测。结果表明,以发展节水面积为主的调控策略在提升灌溉水利用系数的同时,可实现较好的经济效益。 展开更多
关键词 宁夏 扬水灌区 灌溉水利用系数 STIRPAT模型
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盐池地区不同下垫面输沙率特征
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作者 张国军 沈子雅 +5 位作者 魏小燕 任正龑 徐志友 马文涛 程金花 王霄 《中国水土保持科学》 CSCD 北大核心 2024年第2期99-106,共8页
为探究宁夏盐池地区输沙率年内与年际变化特征以及风速与输沙率关系,测量刘窑头风蚀实验站2010—2019年5种下垫面风蚀样地(流动沙丘、半固定沙丘、固定沙丘、灌木林地和荒草地)的输沙率(Q)及风速(V),计算集中度(R_(CD))和集中期(R_(CP)... 为探究宁夏盐池地区输沙率年内与年际变化特征以及风速与输沙率关系,测量刘窑头风蚀实验站2010—2019年5种下垫面风蚀样地(流动沙丘、半固定沙丘、固定沙丘、灌木林地和荒草地)的输沙率(Q)及风速(V),计算集中度(R_(CD))和集中期(R_(CP))、年际变差系数(S_(v))与年际极值比(S_(w)),并将输沙率与风速进行函数拟合。结果表明:1)下垫面影响Q的大小及均匀性,灌木林地平均输沙率最小,年内输沙率集中程度最高,R_(CP)集中在5、6月。10 a间固定沙丘年内最大输沙率出现的时间日期前移,荒草地年最大输沙率出现的日期逐渐后移。2)S_(v)和S_(w)均表明流动沙丘输沙率年际变异程度高于灌木林地。3)指数函数能更好地反映半固定沙丘(R^(2)=0.843)输沙率响应风速特征,其他下垫面为幂函数最佳。4)一元三次函数较好表达各年平均输沙率与风速关系,拟合公式为:Q=65.42-93.36V+42.55V^(2)-6.00V^(3)(R^(2)=0.800)。存在2个风速临界值(1.74和2.99 m/s),改变输沙率对风速的响应。结果可用于盐池地区风沙治理措施建设实践中,可为盐池地区的风蚀综合治理提供科学依据与技术支撑。 展开更多
关键词 输沙率 年内变化 年际变化 宁夏盐池地区
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抗战时期陕甘宁边区对“二流子”的改造
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作者 罗淑宇 李红 《咸阳师范学院学报》 2024年第2期75-79,共5页
抗战时期,陕甘宁边区存在为数颇多的“二流子”群体,他们败坏社会风气、影响经济建设,不利于边区的政权稳定与发展。边区政府采取多种措施对“二流子”展开全面改造,使其从游离于社会主流的“旧人”转变为参与边区建设的革命性力量。深... 抗战时期,陕甘宁边区存在为数颇多的“二流子”群体,他们败坏社会风气、影响经济建设,不利于边区的政权稳定与发展。边区政府采取多种措施对“二流子”展开全面改造,使其从游离于社会主流的“旧人”转变为参与边区建设的革命性力量。深入研究边区政府改造“二流子”的成功举措及经验,对于当今推动乡村建设和加强乡村社会治理具有重要的历史借鉴意义。 展开更多
关键词 陕甘宁边区 “二流子” 改造
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