硅锰结合施用对红壤水稻铁毒害的矫正

Based on the fact that Fe toxicity which is usually characterized by leaf oranging and low yield can be obviously subdued by application of Si or Mn due to counteraction.between Fe and Si or Mn.A pot experiment was conducted with four treatments of CK,Si,Mn and Si Mn to further study the effect of combined application of Si and Mn on rice growth on red earths.Water-soluble SI,Fe and Mn were measured.and electron probe was used to study Si,Mn,Fe and Ca in root cross sections.Combined application of Si and Mn could increas water-soluble Si and Mn but reduce water-soluble Fe,thus being favorable for correctiong Fe toxicity.Electron probe study showed obvous differences of Si,Fe,Mn,and Ca in rice roots between CK and the other three treatments.The combined applicatioin of Si and Mn could reduce leaf oranging and improve rice growth.The Si Mn treatment had a higher plant height,lower number of oranging leaves and a 25.0% higher rice yield than CK and showed a better effect on rice growth than the treatment of sole Si or Mn.     

Contents and bioavailability of rare earth elements in agricultural soils in Hesse (Germany)

With increasing agricultural and industrial use of rare earth elements (REEs), input of REEs into the pedosphere has risen in parallel. Since total REE budgets for soils in Germany are mainly unknown, this pilot study investigates the concentrations of REEs in three loess soil profiles under agricultural land use in the Wetterau region, Germany. There were no significant REE applications in the past, so the presented data can be considered as background concentrations of REEs in soils. In addition to the total REE contents (aqua regia digestion), potentially plant‐available (EDTA) and at actual conditions available, mobile (NH₄NO₃) REEs have been determined for each horizon. Interactions between REE availability and properties of soils are explained after assessing several chemical and physical properties. The results reveal a wide range of total REE contents, ranging from 222 to 423 mg kg^–1. With 10.1% of total REE amounts, the potentially plant‐available proportions of REEs are generally low. In contrast, yttrium, which showed high available proportion of 24.8%, was found to be comparable with Cd. Cerium is the most abundant REE in aqua regia digests, whereas only small amounts in the potentially plant‐available fraction were found. Thus negative cerium anomalies could be concluded concerning its potential availability. Generally, bioavailability of REE had significant correlations between clay contents and Fe and Mn oxides for the majority of REEs. Due to moderately high pH (CaCl₂) in soils (average 6.6) the mobile fraction for most of the elements was not detectible.     

MINERAL ELEMENT DISTRIBUTION AND ACCUMULATION PATTERNS WITHIN TWO BARLEY CULTIVARS

Growth stage effects on distribution of mineral nutrients or beneficial elements phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chloride (Cl), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), molybdenum (Mo), sodium (Na), silicon (Si) and nickel (Ni), and the elements bromine (Br), rubidium (Rb), strontium (Sr), barium (Ba), lanthanum (La), cerium (Ce), and uranium (U) in two barley (Hordeum vulgare L.) cultivars and how the distribution of these elements changed were determined during the 2006–2007 growing season in a field experiment. Barley plants were sampled from the field at shooting, heading, soft dough, hard dough and harvest stages, and mineral nutrients and other elements concentrations of spike, flag leaf, old leaf, and stem samples were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Distribution patterns varied considerably from element to element. At the end of the season much of the Ca, Mg, S, Si, Fe, Mn, Cu, Ni, Sr, Ba, La, Ce, and U were located in the spikes. However, much of the P, K, Zn, Cl, Na, Br, and Rb remained in the old leaves or stem.     

Leaf chlorophyll content as a possible diagnostic mean for the evaluation of plant nitrogen uptake from the soil

The influence of temperature, irradiance, and soil humidity on the nitrogen (N) concentration in some organs, chlorophyll in the leaves, N uptake and accumulation of dry matter in plants of winter wheat was investigated. In the plants grown under equal initial N supplement but in contrasting conditions of the evironment, the correlation between concentration of total N and chlorophyll in the leaves was absent. No interrelationship was found between concentration of total N in the leaves and accumulation of N and dry matter in the whole plants. There is a close correlation between chlorophyll in the leaves, accumulation of total N, and dry matter of the whole plant. It was concluded that chlorophyll is a more stable informative parameter for the estimation of the N uptake from the soil under different growth conditions than leaf N concentration.     

1980—2014年潍坊市深层地温对气候变化的响应

为了研究潍坊深层地温对气候变化的响应,利用潍坊市1980—2014年0.8~3.2 m地温资料,运用线性倾向估计、Mann-Kendall和滑动t检验等统计方法,对潍坊市近35年深层地温的变化特征进行分析。结果表明：0.8~3.2 m地温变化趋势不显著,均未发生突变,一年中,仅夏季各深层地温呈增温趋势。年代际变化上,1980s和2010s各层平均地温均高于1990s和2000s。深层地温在冬季随深度增加,稳定性渐好,夏季反之,一年中,稳定性最好和最差分别发生在夏季和冬季0.8 m地温层。气温对深层地温的影响明显,季、年平均气温与同期各深层地温多呈正相关,随着深度的增加,气温与各层地温的相关性略有降低,这是深层地温变化存在滞后性所致,降水量对各深层地温影响不大。     

不同贮藏方法及激素、稀土等对牡丹种子发芽及幼苗生长的影响

用不同贮藏方法及激素、稀土处理牡丹种子和幼苗,结果显示:冰箱内湿藏、干藏和自然湿藏能有效地提高陈种子的发芽率,用GA3、6-BA、α-NAA、稀土处理不同贮藏方法的陈种子后,GA3、6-BA发芽率表现最佳;新种子幼苗适应性高于陈种子;药用牡丹幼苗优于观赏牡丹;用激素和稀土处理种子及幼苗后,牡丹幼苗生长势表现为用稀土和GA3最好,6-BA和α-NAA稍次.     

Application and Advancement of Reinforced Earth Technique

In this paper, the application of reinforced earth technique, principle and calculation method, new reinforced materials developed and produced are introduced. A few of key technical problems in reinforced earth application is discussed, such as reinforced earth behavior, calculation method, durability of reinforced material, amendment and complement of the current standards. Then, the reinforced earth technique development and advancement were introduced.     

Research on Design Methods for Reinforced Earth Retaining Wall with Cohesive Backfill

For the stability analysis of the reinforced earth retaining wall with cohesive backfill, this paper assumes that the state of failure surface is circular sliding surface and the bearing capacity is straight line relation with capacity and length of the reinforcement strip. These formulas agree with actual state of the reinforced earth retaining wall with cohesive backfill and result in saving reinforcement material in the design.     

葡萄覆土机械化技术发展研究

覆土作业是葡萄种植中劳动强度大、生产效率低的环节,急需实现机械化作业。简述我国葡萄覆土机械化技术发展情况,介绍在覆土机械研制方面的成果,分析应用覆土机械化技术带来的经济、社会及生态效益,展望覆土机械推广应用前景。     

五味子园除草机的研制与应用

设计、制造一种五味子园除草机,并进行田间试验应用与效益分析。该除草机采用手扶拖拉机为配套动力,利用最终传动齿轮,通过除草机的传动箱带动除草轮在地面上滑转来剖切土壤,达到除草和疏松土壤的目的;同时配置培土犁,一次可完成除草、深松、培土复式作业。应用试验表明,该除草机各项技术指标均达到设计标准,能够满足农艺要求。