休闲农业与中国农村剩余劳动力转移探索   总被引：1，自引：0，他引：1  

谢莉  刘昭云  杨载田 《地域研究与开发》2009,28(6)

中国农村剩余劳动力数量巨大,素质偏低,转移难度大.休闲农业兼具农业经济与旅游经济的双重特征,可以促进为旅游业服务的有机农业、高科技农业、特色种植和养殖农业、设施农业及其他农产品加工工业、特色农产品生产的发展,扩大农产品销售市场.对农村剩余劳动力吸纳能力强,可为农村剩余劳动力提供广阔的就业门路.但中国休闲农业产业的继续发展壮大,也有赖于着力培养新一代高素质农民和构建体闲农业各参与主体多赢的一体化格局.  相似文献   

Differences in the abiotic parameters of water in coastal lakes in the light of the EU water framework directive: An example of the Polish southern Baltic coast     

Roman Cieśliński  Maciej Major 《Acta Geophysica》2012,60(4):1159-1179

Coastal lakes have a specific hydrological regime determined by the influence of sea and inland water and the local hydrographic conditions. There are several problems concerning the protection and assessment of water quality of these bodies. The most important features differentiating coastal lakes from other lakes are: high salinity, a wide range of seasonal and short-term water quality changes, and specific aquatic ecosystems adapted to these conditions. These matters have not been sufficiently taken into account in the existing classifications and typologies of lakes in Poland. The problem has not been solved by the establishment of the adequate reference conditions and new guidelines for the classification of water status (which are being prepared according to the Common Strategy for the Implementation of the Water Framework Directive) regarding inland surface waters (rivers and lakes) and marine waters (coastal and transitional). An important issue is to define criteria which would help to distinguish all those hydrographic objects and to establish water quality standards for them.  相似文献   

HJ-1A/B在2012年黄河上中游洪水监测中的应用     

罗玉彬  马浩录  吕莉 《测绘通报》2013,(6):54-58

以黄河内蒙古河段为例,介绍HJ-1A/B星CCD数据在2012年黄河上游洪水遥感监测中的应用,并利用水文、河势变化等实测数据对监测结果进行应用评价。结果表明,HJ-1A/B星CCD数据具有高时间、空间分辨率的特点,是进行大区域、高频次洪水监测的理想数据源,能有效跟踪监测洪水演进过程,并能精确提取河势变化、主河槽展宽、堤防偎水、洪水漫滩等汛情信息,为防洪决策提供及时可靠的汛情数据。  相似文献   

Batch and Column Experiments to Support Heavy Metals (Cu,Zn, and Mn) Transport Modeling in Alluvial Sediments Between the Mogan Lake and the Eymir Lake,Gölbaşı, Ankara     

E. Dişli 《Ground Water Monitoring & Remediation》2010,30(3):125-139

This article describes laboratory batch sorption and column transport experiments that were conducted using heterogeneous alluvial sediments with a wide physical characteristic from wells, located between Lake Mogan and Lake Eymir, Gölbaşı, Ankara. The batch sorption experiment was conducted in two separate systems, that is, single and multicomponents. Single batch experiment was performed to determine equilibrium condition between the heavy metal ions and the soil adsorption sites. The sorption isotherms data from multibatch experiments were used to calculate the sorption parameters. Single batch experiment indicated that equilibrium was attained within 9 days from the start of the sorption test. As a result of multicomponents batch experiments, for Zn and Mn, the sorption process was well described by the Freundlich or Langmuir isotherm model, whereas sorption of Cu was better described by the linear isotherm model. The K_d of Cu were found to be highest in soil 1 (32550.350 L kg⁻¹) and lowest in soil 5 (18170.76 L kg⁻¹). The maximum and minimum sorption capacity values for Zn were found to be in soil 1 (10985.148 mg kg⁻¹) and in soil 2 (8597.14 mg kg⁻¹) units, respectively. [Correction added after online publication 15 July, 2010: In the preceding sentence, the words “minimum” and “maximum” were initially switched.] Similarly, soil 1 (7587.391 mg kg⁻¹) and soil 5 (4908.695 mg kg⁻¹) units provided the maximum and minimum values for Mn. In the column experiments, flow and tracer transport was studied under saturated conditions using conservative tracer to determine the transport parameters. Transport parameter values were obtained by curve-fitting using the nonlinear least-squares optimization code CXTFIT. Results of the column experiments indicated that the dispersivity values obtained for soil samples were in the range of 0.024 to 1.13 cm.  相似文献   

印度湿地和湿地科学研究及管理     

张立 《湿地科学与管理》2010,6(4):62-63

<正>印度由于其高地错落的地形地貌和复杂多变的气候条件,拥有种类繁多的生物生境及丰富的湿地资源。印度天然湿地分布遍及整个疆土,从寒冷干旱的喜马拉雅山区至雨水丰沛的喜马拉雅山谷;从沿雅  相似文献   

MS-215型大直径绳索取心器及其在煤层气井中的应用     

唐胜利  刘凤琴 《煤田地质与勘探》2002,30(5):61-63

根据煤层气井快速、安全的取心要求,结合现场条件,研制了MS-215大直径绳索取心器。文中介绍了取心器的设计思路、结构特点及现场应用效果。结果表明,该取心器设计合理,机构动作可靠,岩煤心直径大、采取率高、提出速度快,尤其适合煤层气井煤心的采取。   相似文献   

唐山市农业洪涝灾害面积与暴雨关系分析     

王猛  高桂芹  王爱军  张莉  万绪江  袁雷武 《气象与环境学报》2020,36(3):93-97

利用唐山市统计局1985—2014年各县逐年播种面积和农业洪涝受灾面积数据资料、唐山地区11个县市气象站逐日降水资料,采用趋势分析、多项式统计回归等方法,对唐山地区农业洪涝灾害时空特征及与暴雨的关系进行分析。结果表明：唐山洪灾面积总体呈微弱的下降趋势,但不显著,与年暴雨日数变化趋势一致。各县域的洪灾以轻到中度为主,占洪灾的80%—100%。唐山地区洪灾与年暴雨量有关（R = 0.78）,但不显著,受灾面积与年暴雨日数显著相关（R = 0.83,P < 0.01）。中等以上洪灾年的暴雨平均暴雨日数为4—6 d、80%县站大暴雨日数为0.7—1.5 d、60%暴雨累积量在300 mm以上。区域种植结构、地形地势、水系河流分布等因素也是导致洪灾的一个重要方面。  相似文献   

NH₄Cl水溶液的微观结构和宏观物性研究          下载免费PDF全文

张宇  李非  费莉婷  纪志永  赵颖颖  郭小甫  刘杰  王士钊  汪婧  毕京涛  张盼盼  张丁予  袁俊生 《盐湖研究》2022,30(4)

通过拉曼光谱、同步辐射X射线散射和密度泛函理论(DFT)模拟,研究了质量分数为1.0 %-28.0 %的NH₄Cl水溶液的微观结构变化。同时在室温下测量了粘度、接触角和电导率。由拉曼光谱和密度泛函理论模拟结果可知,当溶质浓度升高至10.0 %时,在2900 cm_-1^和3100 cm_-1^{附近出现了明显的}N-H作用峰,且随着质量分数的升高,NH₄Cl水溶液中的氢键类型发生了转变。X射线散射结果表明,当NH₄Cl水溶液质量分数升高至10.0 %时,差值对分布函数G(r)在2.98 ?附近出现明显双峰,表明在该浓度下溶液中NH₄₊^-Cl_-^{接触离子对开始成为主要微观作用形式。对}NH₄Cl水溶液的宏观物性研究表明,粘度、接触角和电导率均随着NH₄Cl水溶液质量分数的增加而增大。作者推断,NH₄Cl水溶液中氢键类型的转变、O-H...N键占比增多以及逐渐增加的NH₄₊^-Cl_-^{接触离子对},是粘度和接触角随溶质浓度增加而增加的微观本质因素;电导率的增加与溶液中有效导电离子数量增加有关。  相似文献   

The stability of the terrestrial planets with a more massive 'Earth'     

Áron Süli  Rudolf Dvorak  Florian Freistetter 《Monthly notices of the Royal Astronomical Society》2005,363(1):241-250

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公用机房的硬盘保护措施     

邹书蓉  王永丽  谢海华  张钟澍 《成都信息工程学院学报》1999,(3)

在深入分析硬盘结构及硬盘工作原理的基础上,详细阐述了用软件实现对公用机房硬盘的保护原理和方法,并给出了编程思路。  相似文献