狗牙根和牛鞭草的消浪减蚀作用

剧烈的土壤侵蚀和库岸坍塌是三峡水库消落带的主要生态环境问题之一,而植被恢复是治理消落带的关键措施之一,植物的消浪固土能力是消落带适宜植物配置的重要依据。为了探讨三峡水库消落带典型草本植物狗牙根(Cynodon dactylon(L.)Pers.)和牛鞭草(Hemarthria altissima(Poir.)Stapf et C.E.Hubb.)的消浪减蚀效应,进行了植物消浪和波浪冲刷的水槽概化模拟试验。结果表明,2种植物的消浪效应有较大差异,在周期较长(1.2~1.5 s)时狗牙根平均消浪系数为0.54,明显高于牛鞭草(0.37);而在周期较短时(0.8~1.0 s)则2种草本消浪性能相当,消浪系数均介于0.15~0.30之间。在同样的试验条件下,狗牙根、牛鞭草平均侵蚀模数分别为17.63、57.28 g/(m2·min)。2种草本的减蚀效应均在89%以上,最高可达98.59%。植物的减蚀效应是其地上部分和地下根系的综合作用结果,其中牛鞭草根系的固土贡献率在91%以上,而地上部分仅为7.4%~8.6%;狗牙根根系固土贡献率(71.2%~76.2%)显著低于牛鞭草,但其地上茎干部分贡献率(23.8%~28.8%)要显著高于牛鞭草(P0.05)。可见2种植物都有较好的消浪减蚀效应,总体上狗牙根的消浪能力和综合减蚀效果均要略强于牛鞭草。波浪大小和周期、植被盖度、植物地上部分和根系形态对消浪减蚀效应有重要影响。该研究结果可以为三峡水库消落带的植被恢复和水土保持工程提供一定的参考依据,并可适当的推广到其他水库或湖泊消落带。     

土堤加糙透水式预制块护坡消浪效果模型试验

波浪爬高是确定土堤堤顶高程的重要参数之一,土堤坡面护坡的消浪效果将直接影响波浪的爬高,在土堤护坡工程中,光面混凝土预制块护坡应用最为广泛,但其消浪效果较差,为了解决这一的问题,该文以鄱阳湖上饶片区堤防工程为例,通过增加护坡预制块糙渗系数提出了凹槽嵌固式正六边形预制块、Z字型混凝土预制块和嵌固式四边形空心预制块等3种护坡体型,通过建立护坡消浪室内物理模型试验系统,对比分析了3种预制块相对于传统光面混凝土预制块护坡的消浪效果,提出了3种预制块糙渗系数计算取值。试验结果表明:与光面混凝土预制块护坡相比,该文设计的3种预制块护坡对波浪的爬高都有较大幅度的抑制,坡面上波浪爬高试验结果从小到大依次为凹槽嵌固式正六边形预制块、Z字型混凝土预制块、嵌固式四边形空心预制块、光面混凝土预制块;3种预制块护坡相对于光面混凝土预制块的波浪爬高衰减率(波浪爬高减小比例)依次为35.0%、30.2%和26.23%,计算得到对应的糙渗系数取值分别为0.76、0.77、0.79。综合消浪效果及节约工程成本分析,采用凹槽嵌固式正六边形预制块护坡最佳,具有良好的推广价值和发展前景。     

库区消落带植被生境构筑技术初探

在水库消落带内为植物生长构筑适合的立地条件和生态环境,是消落带植被恢复非常关键和重要的一个步骤。通过对水库消落带的形成特征及其植被生境状况的研究,运用恢复生态学和生态工程学基本理论,确立了库区消落带植被生境构筑技术的概念;并结合清江隔河岩水库消落带植被修复的现场试验,提出了库区消落带植被生境构筑的三种方法,即PEB防冲刷基材生态护坡技术、防冲刷生态型护坡构件、燕窝植生穴。结合具体地质地理条件,三种方法可以组合使用。     

江河堤防植物护坡技术研究成果推广应用

为有效防治土质堤防坡面的水土流失 ,保护堤防安全 ,节约护坡资金 ,研究出了以牛毛草、早熟禾、翦股颖等 8种草本植物为护坡植物 ,河柳等灌木为迎水坡脚防浪林的植物护坡技术。该成果利用植物地上部分形成堤防迎水坡面软覆盖 ,减少坡面的裸露面积和外营力与坡面土壤的直接接触面积 ,起消能护坡作用 ;利用植物根系与坡面土壤的结合 ,改善土壤结构 ,增加坡面表层土壤团粒体 ,提高坡面表层的抗剪强度 ,有效地提高了迎水坡面的抗蚀性 ,大大减少了坡面土壤损失 ,不仅其护坡效果显著 ,且投资仅为工程护坡的 10 9%～ 2 2 .1%。     

“护坡与生态修复专家”让陡峭岩石上长青草——三峡大学宜昌绿野环保工程有限公司

拥有四项边坡治理专利技术 1）植被混凝土护坡绿化技术 2）防冲刷基材（PEB）生态护坡技术 3）矿山废弃地植被生态修复技术 4）滨水岸坡生态修复及库区消落带植被恢复技术     

“护坡与生态修复专家”让陡峭岩石上长青草——三峡大学宜昌绿野环保工程有限公司

拥有四项边坡治理专利技术 1）植被混凝土护坡绿化技术 2）防冲刷基材（PEB）生态护坡技术 3）矿山废弃地植被生态修复技术 4）滨水岸坡生态修复及库区消落带植被恢复技术     

三峡大学湖北宜昌绿野环保工程有限公司

宜昌绿野环保工程有限责任公司是一家集研究、设计、生产、施工于一体的高新技术环保企业。自公司成立以来．一直致力于岩石边坡、混凝土边坡、废弃矿山、滨水岸坡和消落带坡面的护坡与生态修复。公司在全国建立了多个技术推广中心，工程推广已覆盖华中、华东、华南，西南等地区。     

巢形装配式混凝土生态护坡构件设计

传统的边坡治理各有其局限性。2005年辽宁省水土保持研究所研究出的巢形装配式生态护坡构件,由主副巢两部分构成,主巢可控制坡面水土流失,具有护坡功能,副巢可沉积坡面流失的土壤或容纳客土,以满足栽植植物的要求,且造价低、施工快,可适宜用于除水域边坡外的可砌护的边坡。     

三峡大学湖北宜昌绿野环保工程有限公司

宜昌绿野环保工程有限责任公司是一家集研究，设计，生产，施工于一体的高新技术环保企业。自公司成立以来一直致力于岩石边坡混凝土边坡，废弃矿山，滨水岸坡和消落带坡面的护坡与生态修复。公司在全国建立了多个技术推广中心，工程推广已覆盖华中，华东，华南，西南等地区。     

高速公路生态护坡技术的水土保持效应研究

对高速公路生态护坡工程开展试验观测。研究探讨生态护坡技术的水土保持效应。结果表明，在高速公路高陡边坡上采用生态护坡技术建植草本植被。在短期内可完全覆盖坡面，水土保持效果显著，可抑制边坡侵蚀的发育，有效控制坡面沟蚀的发生，在中雨到暴雨的情况下，边坡径流系数在15．97％以下，土壤流失量极小。生态护坡技术的水土保持机理主要与草本植被对降雨的截留、雨滴能量的削减、坡面径流的抑制、根系的锚固与加筋作用，以及生态护坡技术本身的工艺特性有关。     

Physical Properties of the Soils of Sibay City of the Republic of Bashkortostan

Eurasian Soil Science - The results of the study of the properties of urban soils of the city of Sibay located in the mining region of the Republic of Bashkortostan are presented. A specific...     

食用仙人掌萎蔫气象条件分析

塑料大棚内种植的食用仙人掌在土壤墒情较好时也有萎蔫现象发生，通过试验观测和对仙人掌生理习性的分析，发现阴雨过后天气突然放晴温度急剧上升易使仙人掌发生萎蔫现象，并提出了田间管理的应对措施。     

Heterogeneity of Organic Matter of Aggregates of Protocalcic Chernozems

Eurasian Soil Science - Layers were step-by-step removed from macroaggregates (2–1 mm in diameter) of Protocalcic Chernozems via successive abrasion in a revolving rotator during 5, 10, 15,...     

青海省耕地资源开发利用分析及对策研究

分析论述了青海省耕地资源开发利用的现状、特点和问题。在此基础上,提出了对青海省耕地资源进行研究的框架体系和思路,同时基于GIS/RS技术设计了相关的技术路线。最后依据所做设计对青海省耕地资源开发利用做了初步分析,并进行了相关的对策研究分析。     

Characterization of physical and chemical properties of Varzea soils of Goias State of Brazil

Abstract

Brazil has approximately 30 million hectares of lowland areas, known locally as “Varzea,”; distributed throughout the country. Soils in these areas have the potential to support agricultural production, but very little is known about their fertility. The current experiment was undertaken to characterize the chemical and physical properties of representative “Varzea”; soils collected at 0–20, 20–40, 40–60, and 60–80 cm depth intervals from 23 sites in Goias State of Brazil. Organic matter contents averaged 42 g/kg in the surface 20 cm of soil and should make a significant contribution to overall nutrient availability. Soil pH increased slightly with depth from a mean value of 5.2 in the surface 20 cm of soil to a mean value of 5.4 in the 60–80 cm depth interval. Several soils had exchangeable Al values ≥ 1.0 cmol Al/kg, but soil Al saturation was generally less than the 60% level frequently associated with Al toxicity. However, cereal and legume production could benefit from lime addition in many of these soils. Although base saturation was fairly low in some soils, exchangeable Ca and Mg levels were, in general, adequate throughout the profile. Extractable P levels were adequate in most surface soil samples. Extractable K levels in these soils were generally low, and the application of K fertilizers should be beneficial, especially in conjunction with lime addition. The high clay content “Varzea”; soils of the Brazilian lowlands have some drainage problems but generally exhibit favorable chemical properties for crop production when compared to soils of the well‐drained Cerrados.     

Estimation of potential nitrogen-fixing activity of agrophytocenoses soils of the subtropical zone of Russia

An estimation of potential nitrogen-fixing activity of various soil types under agrophytocenoses of tea, filbert, peach, and pawpaw which grow in the area of Greater Sochi is given. High indicators of nitrogen fixation activity in the soil in the course of vegetation were characteristic of agrocenoses of pawpaw, peach, and filbert. The lowest level of nitrogen fixation was noted in the soil of a tea plantation. A negative correlation dependence of potential nitrogen-fixing activity on the acidity of the soil solution was established. A study of the seasonal dynamics of the activity of nitrogen fixation of soils of agrocenoses of the subtropical zone of Russia made it possible to distinguish a less active winter and more active spring-summer-autumn periods.     

Kinetics of Popping of Popcorn

The rate of popping of popcorn was measured in oil and in air. Kinetic data for lifetimes of individual kernels from a large population were obtained in oil at six constant temperatures (180–250°C) and also in an air‐popper at 202°C. The data are characterized by an induction period, which is, significantly, followed by a first‐order decrease in the number of unpopped kernels versus time. The activation energy for the first order process is 166.7 kJ/mol between 180 and 210°C, and 53.8 kJ/mol between 210 and 250°C. These data are consistent with a model that assumes 1) that the rate of heat transfer into a kernel follows Newton's law of cooling; 2) that in a sample of kernels there exists a distribution of critical pressures; 3) that for an individual kernel, the probability of popping is directly proportional to the difference between the internal aqueous vapor pressure and the kernel's critical pressure; and 4) that the measured rate constant at any temperature is an average overall of the kernels in the sample with critical pressures equal to or less than the internal aqueous vapor pressure. Minimum popping temperatures predicted by the model are 181 ± 2°C (oil) and 187 ± 2°C (air), in good agreement with previously reported direct measurements.     

物联网安全及解决措施

物联网是一个集信息通信、数据交换、传感器技术与软件工程于一体的综合性产业,探讨和分析了物联网的结构体系与发展中遇到的安全问题。     

荔枝种子结构的扫描电镜观察

荔枝种子从果实中剥离出来后, 即使在室内条件下, 也极易失水干缩, 潮湿环境中又易发霉而腐烂。扫描电镜观察表明: 种皮上布满纹孔, 水分散失面积很大; 种脐部为疏松的海绵组织, 且营养丰富。据此, 生产上应对种子彻底清洗, 并保存于适当湿度的环境中, 以提高其发芽率。