不同施肥处理对棕壤几个肥力指标的影响

23年定位试验结果表明:土壤有机碳、全氮和碱解氮、生物氮量以:高量有机肥区>低量有机肥区>化肥区>对照。土壤C/N基本维持在11~16之间。单施化肥处理土壤微生物碳量降低,Kos值高于其它施化肥处理,有机无机肥配合施用,结合态腐殖质含量明显下降,松结态/重组腐殖质的比值和松/紧比值也有所降低。有机无机配施各处理土壤微生物碳量,以及土壤松结态、稳结态、紧结态腐殖质的含量显著升高,提高松结态/重组腐殖质和松/紧的比值;不同用量的施有机肥处理土壤微生物碳量与对照相比差异不显著,Kos值下降,其他指标均升高。     

参根周皮层锈斑有机组分来源的探讨

本文采用熊田法比较研究了白皮 /红皮参根周皮层提取物的组分。结果表明 ,红皮参根周皮层确实存在具有天然腐殖物质一般特性的有机化合物———类腐殖质物质。参根周皮层死亡组织的分解及其腐殖化是这类物质的重要来源之一。为认识参根锈斑物质的形成提供了新资料     

黑麦草培肥细质沙土的初步研究

黑麦草Lolium是禾本科黑麦草属植物,其根系发达,在0～30cm的土层中,总根量(2505kghm-2)是小麦总根量(960kghm-2)的2.61倍,其根系富含磷、钾营养,长期施用既可以增加土壤氮素,也有利于土壤磷、钾含量的增加。黑麦草轮作中土壤有机质含量比小麦轮作高4.48%,土壤碱解氮和速效钾含量也分别高30.70%和41.37%,说明黑麦草根茬对增加土壤养分、培肥地力作用显著。与3%麦秸相比,施用黑麦草对形成各种形态腐殖质的作用均较大;与羊粪相比,施用相同水平的黑麦草对形成松结态腐殖质的作用更大,而对形成紧结态腐殖质的作用相当;与腐殖酸铵相比较,施用相同水平的黑麦草对形成松结态腐殖质的作用较小,而对形成紧结态腐殖质的作用则较大。施用不同水平的黑麦草比施用相应水平的羊粪和3%麦秸的原土复合度为高;但其原土复合量有高有低。与腐殖酸铵相比较,施用黑麦草有利于提高原土复合量,但对原土复合度的影响不大。     

长期定位试验条件下红壤性水稻土有机质的变化

通过22年长期定位试验,研究了红壤性水稻土有机质的含量及其结合形态在3种稻作制、3种有机肥施用水平及2种地下水位深度条件下的长期演变规律,结果表明:红壤旱土改水田后,土壤有机质含量逐渐增加,各处理平均增长15.2gkg-1,增长率达98.9%。不同稻作制间,以稻—稻—冬泡处理土壤有机质增长幅度最大,21年共增加了18.0gkg-1,增长率达116.9%;稻—稻—冬绿处理次之,共分别增长15.8gkg-1和102.6%;稻—稻—冬油处理最低,仅分别增长11.9g kg-1和77.3%。不同有机肥施用水平间,以高量有机肥处理土壤有机质增长最快,21年共增加了17.9gkg-1,增长率为116.2%;常量有机肥处理次之,共分别增加16.1gkg-1和104.5%;化肥处理最低,共分别增加11.8gkg-1和76.6%。不同地下水位深度对土壤有机质积累的影响不显著。土壤腐殖质结合形态以紧结态为主,占腐殖质总量的50～70%,松结态腐殖质次之,占20～40%,稳结态腐殖质最少,仅5～11%。冬种处理土壤腐殖质的松/紧比大于冬泡处理。施用有机肥料能提高土壤腐殖质的松/紧比。     

福州市几种菜园土肥力特性的初步研究

对福州市起源于红壤和冲积物母质上的几种菜园土的土壤及其微团聚体性质测定结果表明 :经长期培育的高度熟化菜园土 ,其土壤养分贮量和有效养分含量均大幅度提高 ;腐殖质HA/FA、胡敏酸芳构化度和腐殖质氧化稳定性均明显增大 ;不同结合态腐殖质以松、紧结合态为主 ,二者绝对含量均明显增加 .这些决定了菜园土具有很强的供肥能力和良好的土壤结构     

长期施肥对褐土有机无机复合性状演变及其与肥力关系的影响

通过8年长期定位试验,研究了不同施肥方式对褐土有机无机复合状况及腐殖质结合形态的影响。结果表明,长期不施肥使土壤有机碳、重组有机碳、原土复合量、松结态和紧结态有机碳含量明显下降,松/紧值降低,原土复合度上升;长期单施常量NPK化肥有同样的趋势;长期单施增量NPK化肥可大体保持土壤肥力水平不下降,但成本较高;采用有机肥(物)料配施常量NPK化肥,可明显提高土壤有机碳、重组有机碳含量和原土复合量以及土壤松、稳、紧各级结合态有机碳含量,增加松结态占重组有机碳比率,提高松/紧值,增强土壤调控能力。土壤有机无机复合状况及腐殖质结合形态是评价褐土培肥效果和标志土壤肥力演变的重要指标。     

田间定位施肥对土壤腐殖质组分数量与特性的影响

依据Pallo方法对土壤腐殖质进行分组,初步研究了黑土田间定位施用有机肥、化肥及有机肥配施化肥对各组分数量与特性的影响。结果表明:通常化肥不会对土壤腐殖质各组分的数量与特性产生明显影响。施用有机肥使各组分的数量明显增加;同时,施用有机肥使各组分的分子结构变得简单化。从有利于提高土壤肥力和作物产量的角度来看,施肥应采用有机无机肥配合施用,在配施化肥条件下可以适当提高有机肥的用量。     

高寒草甸植被土壤腐殖质组成及性质的研究

不同草甸植被下土壤有机质含量变化在70.0～122.8gkg-1之间,同时,腐殖质特性亦存在较大差异。采用熊田法研究表明,可提取腐殖质中胡敏酸所占比率为47.99%～56.98%,游离胡敏酸(fHA)比率为51.67%～60.10%,游离富里酸(fFA)比率为80.01%～86.46%;此外,不同草甸植被下土壤腐殖质的相对色度(RF),E4也有明显差异。     

四川成都经济区土壤腐殖质重金属元素含量特征研究

通过对四川成都经济区16件土壤样品腐殖质组成及其各组分中重金属元素含量的分析表明,胡敏素是土壤腐殖质的主要组成部分,富里酸和胡敏酸次之.土壤腐殖质中重金属元素含量占土壤伞量20%～44%,是土壤重金属污染元素主要存在方式.重金属元素在腐殖质不同组分中的含量具有很大的差异,Cr主要赋存在胡敏素中,Cd、As、Cu、Zn等元素主要赋存在富罩酸中.各重金属元素在腐殖酸中含量较高,富里酸中的含量均大于胡敏酸,其机理是富里酸对重金属元素的络合是腐殖酸与重金属相互作用的主要方式.     

土壤腐殖质状况的宇航监测

本文汇总了苏联在1981—1985年期间遥感探测土壤腐殖质含量的技术进展。展示了反射率与腐殖质含量之间相关性的校正曲线,以及数据库的组成;多光谱指标的应用以及同步综合某些土壤组分的大量光学效应的回归分析,各种比例尺的腐殖质遥感制图;最后讨论了最近15—25年中土壤腐殖质动态变化的宇航监测。     

基于决策树方法的罗布泊“大耳朵”干盐湖区盐壳分类研究

本研究在野外综合考察基础上结合试验分析数据及遥感影像上提供的信息建立了罗布泊“大耳朵”干盐湖区盐壳分类体系,采用决策树方法对ETM＋遥感影像进行分类,经过混淆矩阵检验,分类总精度达到86.3%,Kappa系数为0.8420。结果表明,罗布泊“大耳朵”干盐湖区不同盐壳类型在空间上呈环状分布与“耳轮”影像特征大致吻合;影像上同一条带的盐壳表现出相间分布的特点;相似形状的盐壳受地表湿度影响在遥感影像上呈现不同色调。     

Spectral properties and hydraulic conductance of soil crusts formed by raindrop impact

In this study, a controlled spectral investigation of the properties of structural crust, using infiltration rate as an indicator, was carried out, on a grumusol (typic chromoxerets) soil. The scope of this paper is to investigate the spectral relationship between structural crust and the infiltration rate and some related properties of a grumusol soil. Structural crust is a thin compact layer generated on the soil's surface after rainstorm events due to raindrop energy. The crust, which is a result of physical segregation and rearrangement of soil particles, affects some of the soil's physical properties, such as infiltration, run-off and soil erosion. A set of soil samples was subjected in the laboratory to increased levels of cumulative energy from a simulated rainstorm, while measuring the infiltration rate. The result was a set of soil samples with increased levels of crusting and correspondingly reduced infiltration rates. After drying the soil samples, their spectral parameters across the SWIR region (1.2 w m-2.4 w m) were studied in the laboratory. Empirical relations were found between the infiltration rate and reflectance values (either in raw or in first derivative domains). A spectral ratio manipulation, using a fog type rain treatment (characterized as having no rain energy) as reference, confirmed that, within the spectrum, changes in both albedo and absorption enabled the crust to be detected using reflectance radiation. This is basically because fine (mostly clay) mineral enrichment processes occurred at the surface of the crusted soil. These minerals (montmorillonite, calcite) are spectrally active across the selected spectral region. Although further study is required to fully account for other soils, rainstorm energies and water qualities, this technique suggests great potential as a tool for rapid, non-destructive, in situ assessment of crusted soil properties.     

A Crust-based Method of Reconstructing Human Bone

We present a crust-based procedure for modeling human being’s bone, which is based on voronoi diagram and its dual, Delaunay triangulation. In three-dimensional space, the crust algorithm can generate a 3D-model using a set of sample points. The purposes of this paper is to extract precise contour from CT series, then refer to these contours as sample points, and then apply the crust algorithm to these sample points to get three dimensional mesh.     

铰接履带式海底采矿车越障性能仿真研究

针对产于复杂恶劣地形海山表面的深海矿产资源钻结壳,提出了钴结壳采矿车采用铰接式履带车的技术方案,利用机械系统动力学仿真软件ADAMS/ATV履带车工具包,开发了铰接履带式海底采矿车的三维动力学模型和虚拟样机,进行了其通过垂赶障碍和沟槽地形的越障性能仿真研究和结果分析.仿真研究表明,铰接履带式海底采矿车建模正确,仿真真实,越障性能优良,且超过我国钴结壳采矿车技术要求,仿真数据可为物理样机研制提供技术参考.     

Analysis of TerraSAR-X data sensitivity to bare soil moisture, roughness, composition and soil crust

Soils play a key role in shaping the environment and in risk assessment. We characterized the soils of bare agricultural plots using TerraSAR-X (9.5 GHz) data acquired in 2009 and 2010. We analyzed the behavior of the TerraSAR-X signal for two configurations, HH-25° and HH-50°, with regard to several soil conditions: moisture content, surface roughness, soil composition and soil-surface structure (slaking crust).The TerraSAR-X signal was more sensitive to soil moisture at a low (25°) incidence angle than at a high incidence angle (50°). For high soil moisture (> 25%), the TerraSAR-X signal was more sensitive to soil roughness at a high incidence angle (50°) than at a low incidence angle (25°).The high spatial resolution of the TerraSAR-X data (1 m) enabled the soil composition and slaking crust to be analyzed at the within-plot scale based on the radar signal. The two loamy-soil categories that composed our training plots did not differ sufficiently in their percentages of sand and clay to be discriminated by the X-band radar signal.However, the spatial distribution of slaking crust could be detected when soil moisture variation is observed between soil crusted and soil without crust. Indeed, areas covered by slaking crust could have greater soil moisture and consequently a greater backscattering signal than soils without crust.     

基于分形理论的富钴结壳微地形可视化技术

通过应用海底富钴结壳微地形的分形性质及其微地形分形插值重构方法，在Visual C＋＋开发环境下，引入OpenGL三维图形标准，实现了海底富钴结壳微地形的可视化，为富钴结壳矿床的开采提供了技术支持，也为一般的地形的可视化、真实性和可测量性等问题提供了解决途径。     

中国北方红色土壤分类问题的探讨

现今出露于中国北方地表的红色土壤是在红色古土壤和红色古风化壳上发育的,而且大多经历了不连续的成土过程。中国北方红色土壤分布广泛、成因复杂,在分类中还存在着许多问题。从20世纪70年代末至今,我国土壤分类经历了由土壤发生学分类向土壤系统分类的重大转变,对北方红色土壤的分类也进行了多次修订。虽然每次修订都有所改进,但直到目前关于北方红色土壤的分类位置问题仍没有得到彻底解决。因此,今后需要对中国北方红色土壤的形成过程及土壤的性态特征和理化性状进行深入研究,建立适合北方红色土壤系统分类的诊断层和诊断特性,以明确中国北方红色土壤在系统分类中的位置,进一步完善中国土壤系统分类。     

Multivariate Bayesian cognitive modeling for unsupervised quality control of baked pizzas

The present article describes a Bayesian multivariate methodology developed for unsupervised quality control of pizzas based on RGB color attributes. A sensory experiment was done to define the readiness point ground truth. During the validation phase, different pizza samples were baked at a different temperature. The cheese and crust color patterns were statistically compared against the ground truth to check the readiness point. Results show that the proposed methodology presents a good performance demonstrating that color attributes can be used as an unsupervised quality control using traditional statistical methods.     

A One-Step Crust and Skeleton Extraction Algorithm

We wish to extract the topology from scanned maps. In previous work [GNY] this was done by extracting a skeleton from the Voronoi diagram, but this required vertex labelling and was only useable for polygon maps. We wished to take the crust algorithm of Amenta et al. [ABE] and modify it to extract the skeleton from unlabelled vertices. We find that by reducing the algorithm to a local test on the original Voronoi diagram we may extract both a crust and a skeleton simultaneously, using a variant of the Quad-Edge structure of [GS]. We show that this crust has the properties of the original, and that the resulting skeleton has many practical uses. We illustrate the usefulness of the combined diagram with various applications. Received January 17, 1999; revised December 1, 1999.     

Characteristic spectral reflectance of a semi-arid environment

Comprehensive information on the spectral reflectivity of several desert habitats and of dominant desert vegetation are presented. No previous high resolution spectral reflectance measurements were made in this semi-arid Sahara-Arabian phytogeographic zone. Due to the relative homogeneity of the region, in terms of terrain type and comprehensive sampling, the local scale surface albedo was estimated to be about 30–33 per cent. It was also possible to revisit the currently accepted hypothesis on the observed contrasts in surface reflectivity between protected and overgrazed areas. It seems that anthropogenic activities, which prevent the accumulation of crust or destroy an existing crust, rather than the overgrazing mechanism itself, are the main reasons for the sharp contrast between the protected and overgrazed surfaces.