基于AquaCrop模型的东北春麦区小麦冠层生长模拟研究

在AquaCrop作物模型数据库组建的基础上,应用该模型对东北春小麦冠层生长进行模拟。结果表明,除2010年呼玛地区模拟值低于实测值外,其余年份和地点的模拟值均高于实测值,IoA在0.726～0.995之间,模拟值与实测值的一致性较为理想;AquaCrop模型能较好反映正常年份下春麦生育活动,模型模拟情况与各地观测到的冠层发育情况较为一致。但对极端气候下的春麦冠层发育的模拟效果较为一般。在以后的研究中,需进一步对气象参数做出修正,以更好地应用于小麦的生产和预测。     

甘肃省元帅系苹果叶营养元素含量标准值研究

不同地区苹果不同品种叶营养元素适宜值存在差异,苹果叶片营养标准值的确定对养分管理具有指导意义.通过对甘肃省元帅系苹果叶片营养水平的研究表明,营养元素变异规律呈现常量营养元素＜微量元素;不同产量苹果园,高产园叶片N、P、Ca、Mg、Zn、Mn含量值显著高于低产园,而铁含量显著低于中、低产园,K、B含量差异不显著;叶片矿质营养N、P、K、Ca、Mg、B含量值遵从正态分布,而Cu、Fe、Mn、Zn呈偏态分布(x2分布).对符合正态分布的元素采用概率分级法1～5级分级,分别对应叶营养元素含量标准值中的缺乏、低值、正常值、高值、过高5个数值范围,各级出现的叶样概率分别为10％、20％、40％、20％和10％,叶分析值为(X-0.5246S)～(X+0.5246S)可作为标准值中的正常值范围,这与高产园分析值十分接近;对呈x2分布特征的元素,参照高产园的叶分析值对概率分级法进行矫正,制定出甘肃省元帅系苹果叶营养元素含量标准值.与国内外标准相比,甘肃元帅系苹果叶标准值表现出N、P、K、Mn、Zn、B水平正常,Ca、Mg、Cu偏高,Fe极高的特点.     

Influence of the ionic strength of nutrient solutions and tropical acid soil solutions on aluminum activity

Aluminum (Al) activity was determined in nutrient solutions and in acid soil solutions. Aluminum concentrations in the solutions ranged from 7.4 μM to 370.3 μM giving values of ionic strength of nutrient solutions higher than the values of acid soil solutions. The increase of ionic strength values was due to the increase of Al concentrations. The values of Al activities of 20 uM in the acid soil solutions were noticed when Al concentrations were lower than 70 μM. On the other hand, these values of Al activities in nutrient solutions were noticed only when the Al concentrations were higher than 70 μM. This study demonstrates why it is important to use higher Al concentrations in nutrient solutions to obtain Al toxic effects.     

Effect of different amounts of acid application in fertigation on calcareous soil pH

This study was carried out during 3 different periods and in 24 various greenhouses. Average pH values of the irrigation water (7.61, 7.55, 7.29) and average soil pH values before fertigation (7.61, 7.57, 7.55) were measured. Average fertigation pH values were measured to be 6.80, 6.61 and 6.44. Depending on fertigation pH values, average soil pH values decreased at the rate of 0.52, 0.65 and 0.60 compared to those before fertigation. Although average soil pH decreased depending on acid doses used by growers in the greenhouse, this decrease was not sufficient. In conclusion, if growers fertilize with lower fertigation pH doses, availability of plant nutrients can be increased. Additionally, this may lead to less fertilizer use by increasing availability of fertilizers used in fertigation in soils that have calcareous and high pH values. It is clear that further studies should be done with this approach.     

阿勒泰地区参考作物蒸散量时空变化特征

基于阿勒泰地区7个气象站1961—2012年逐日气象资料,采用Penman-Monteith模型计算了逐日参考作物蒸散量,运用Mann-Kendall非参数检验法、小波分析法,并结合ArcGIS软件对作物参考蒸散量的时空变化特征进行了研究。结果表明:阿勒泰年和春季作物参考蒸散量呈增加趋势,而夏季、秋季和冬季作物参考蒸散量呈减少趋势。年和夏季的作物参考蒸散量分别在1994年、1992年发生突变,而春季、秋季和冬季的作物参考蒸散量则没有发生突变。年和四季的作物参考蒸散量都存在27 a的周期。空间分布上,年、春季、夏季和秋季的平均作物参考蒸散量呈自阿勒泰市南部和福海县西北部向东部、南部和西部逐渐递减的变化趋势。而冬季作物潜在蒸散量大致呈现自西向东逐渐递减。变化趋势上,春季潜在蒸散量在空间上都呈增加趋势,而年、夏季、秋季和冬季的潜在蒸散量在阿勒泰的东部呈增加趋势,在西部则呈减少趋势。     

损伤苹果微弱光特性的试验研究

为了探索以微弱光特性识别损伤果品的新方法,以富士苹果为试验材料,研究了撞击和静压损伤苹果微弱光值的变化规律.试验结果表明:撞击和静压损伤皆影响果品的微弱光,这种影响存损伤瞬间尤其明显;损伤面积较大以及损伤深度较大的果品,微弱光的变化比较明显;在苹果发生损伤后8 h内,苹果的微弱光值不再保持稳定,出现了一定的跃变,而损伤的程度越严重,波动的幅度越人:破损后储藏期问,撞击损伤苹果的吸光值持续降低并出现缓慢波动;静压损伤苹果的吸光值持续降低后急剧下降,而同期的无损苹果的吸光度的变化则非常缓慢.研究表明:采用微弱光检测数据,能很好的将受损苹果从苹果中区分出来.微弱光作为一种灵敏的检测技术,可以应用于损伤苹果品质检测.     

Effects of Postharvest Processing on Texture Profile Analysis of Cooked Rice

The effects of drying conditions, final moisture content, and degree of milling on the texture of cooked rice varieties, as measured by texture profile analysis, were investigated. Instrumentally measured textural properties were not significantly (α = 0.05) affected by drying conditions, with the exception of cohesiveness. Cohesiveness was lower in rice dried at lower temperatures (18°C or ambient) than in that dried at the higher commercial temperatures. Final moisture content and degree of milling significantly (α = 0.05) affected textural property values for adhesiveness, cohesiveness, hardness, and springiness; their effects were interdependent. The effects of deep milling were more pronounced in the rice dried to 15% moisture than that dried to 12%. In general, textural property values for hardness were higher and those for cohesiveness, adhesiveness, and springiness were lower in regular-milled rice dried to 15% moisture than in that dried to 12%. In contrast, hardness values were lower and cohesiveness, adhesiveness, and springiness values were higher in deep-milled rice dried to 15% moisture than in that dried to 12% moisture. Deep milling resulted in rice with lower hardness values and higher cohesiveness, adhesiveness, and springiness values.     

Comparison of dietary fiber contents of selected baby foods from two major brands in Canada using three methods

Of the two major brands of baby foods in Canada, one reports lower dietary fiber values than the other, although the products appear to be similar. To investigate the reasons for this discrepancy, seven selected samples of baby foods from both brands were analyzed for total dietary fiber (TDF) according to the Mongeau (rapid Health Protection Branch; HPB) method. Two cereals were also analyzed by using the Prosky and the Englyst (nonstarch polysaccharide; NSP) methods as an internal check on the methodology as well as a means of investigating the reasons for the discrepancies. The sampling included at least four different lots of each product (cereals, fruits, vegetables, and legumes). Each lot was analyzed individually. The TDF values determined using the rapid HPB method were in agreement with those obtained by other dietary fiber methods. Comparison between manufacturer-reported and measured values showed that the low values reported in brand A products were due, in part, to under-reporting of TDF content: measured TDF values were significantly higher than manufacturer-reported values. For brand B products, the manufacturer-reported and measured TDF values were in general agreement. This shows that a large part of the discrepancy between the two brands was due to methodological problems associated with measuring TDF in brand A. Differences in TDF content were also apparent as shown by the fact that brand A TDF values were consistently lower than those of brand B when both were measured by the same method. The differences in TDF content were not explained by differences in the polysaccharide composition of the fiber residues or by differences in water content. Although the limited number of samples does not allow any general conclusion about the TDF content of specific brands, the results show that formulation and/or manufacturing differences may influence TDF values in processed baby foods.     

Assessment of protein quality methodology for infant formulas

Rat bioassay was used to assess the protein quality of powdered infant formulas and to evaluate the feasibility of using modified casein diets (containing the same source and level of fat and carbohydrate contributed by the infant formulas) as reference standards. Modification of the casein diet to match the milk-based formulas caused a significant reduction in weekly protein efficiency ratios (PER) and net protein ratios (NPR) at the third and fourth weeks. Modification of the casein diet to stimulate the soy-based formulas had no significant effect on NPR values; PER values were more varied. When PER and NPR values of the powdered milk-based formulas were expressed relative to the unmodified reference standard, the relative values were lower than when each matched reference was used. With few exceptions, the relative weekly PER values of the soy-based formulas were similar regardless of the standard used. The relative NPR values of the formulas had a pattern similar to the relative PER values. The data indicate that protein quality evaluation of infant formulas using rat bioassay warrants the use of matched casein reference diets for each type of formula.     

不同包装对山核桃脂肪氧化的影响（简报）

为了选择合适的包装措施以减缓山核桃仁中油脂在贮藏期间的氧化酸败,延长其贮藏期,研究了用聚乙烯塑料膜（Polyethylene,PE）和聚乙烯塑料铝箔膜（Polyethylene/Al,PE/Al）的普通包装与PE、PE/Al的真空包装,4种不同包装措施对山核桃贮藏过程中油脂氧化的影响。通过不同包装对山核桃油脂的酸价、碘价、过氧化值、p-茴香胺值和脂肪氧合酶活性在贮藏过程中的变化情况的影响,确定适合山核桃的包装形式。试验结果表明PE/Al真空包装能有效减缓山核桃油脂的氧化进程,从而延缓山核桃的品质的下降,延长其货架期。     

Soil testing of horticultural substrates for cyclamen and poinsettia

Abstract

The 1: 1.5 water, Spurway and saturated media extract procedures were evaluated for cyclamen and 1: 1.5 water extract for poinsettia growing in bark, peat and peat + soil using nutrient uptake as the criterion. In addition, the N, P, and K desirable values (DV) to give maxi Timm dry wt in two harvests and to give maximum growth rate for various growing periods, in samples taken at the start of the trial and midway through the trial, were determined using a quadratic function for both crops. The relationships between N, P and K uptake and the soil test values were generally very good, although the methods overestimated N uptake and underestimated P uptake in bark‐relative to peat. Underestimation of P uptake in peat + soil was even greater. The initial desirable N soil test value in relation to midterm harvest (IDVM) for cyclamen in peat varied from 100–104 ppm for water, 303–312 ppm for saturated media and 44–46 for Spurway extraction. The midterm soil test value in relation to final harvest (MDVF) values varied from 125–136 ppm for water, 471–502 for saturated media and 44–53 ppm for Spurway extraction. Corresponding values in bark were generally higher. The IDVM and MDVF values using the water extract for poinsettia were 180–225 ppm and 155–215 ppm in peat and bark respectively. It was not possible to determine phosphorus IDVM values for cyclamen due to the poor fit of the response curve. The phosphorus MDVF values in peat for cyclamen were 8.1–8.8 ppm for water, 24.5–26.7 ppm for saturated media and 3.2–3.5 ppm for Spurway extraction. The corresponding values in bark were about half of those values and even lower in peat + soil. The phosphorus MDVF values in peat for poinsettia were 14–19 ppm and in bark 4–4.5 ppm for the water extraction. It was not possible to determine K desirable values for cyclamen because of lack of adequate plant response from K application. Potassium IDVF and MDVF values for poinsettia in peat were 100–136 and 80–126 ppm respectively. The DV obtained using growth data were broadly similar to those using plant dry wt. The desirable plant nutrient levels for maximum dry wt of cyclamen at final harvest varied from 1.9–2.4% for N, 0.10–0.17% for P and 1.0–1.7% for K. The DV values for poinsettia at mid harvest were 3.6–4.6% N, and at final harvest 2.7–3.6% N and 0.18–0.37% P.     

Comparison of the reflectances of black plant fragments in melanic Andisols with those of fresh charcoal from modern fires

We investigated the reflectances of black plant fragments in melanic Andisols and of fresh charcoal produced during modern grassland and forest fires with the aim of clarifying the origin of fragments in melanic Andisols. The reflectance values of most Andisol plant fragments were less than 2%; all values were below 3%. These values are considered to have formed at temperatures of at least 200°C, indicating that these fragments are charcoal fragments. The reflectances of the fragments in melanic Andisols were similar to those of grass charcoal from grassland fires rather than wood charcoal produced during forest fires. This finding indicates that most charcoal fragments in melanic Andisols are the product of grassland fires. The small difference between the reflectance values of the charcoal fragments in the Andisols and the grass charcoal is possibly derived from the fact that charcoal fragments with lower reflectance are more likely to be retained in the soil than fragments with higher reflectance values.     

Comparison of the reflectances of black plant fragments in melanic Andisols with those of fresh charcoal from modern fires

Abstract

We investigated the reflectances of black plant fragments in melanic Andisols and of fresh charcoal produced during modern grassland and forest fires with the aim of clarifying the origin of fragments in melanic Andisols. The reflectance values of most Andisol plant fragments were less than 2%; all values were below 3%. These values are considered to have formed at temperatures of at least 200°C, indicating that these fragments are charcoal fragments. The reflectances of the fragments in melanic Andisols were similar to those of grass charcoal from grassland fires rather than wood charcoal produced during forest fires. This finding indicates that most charcoal fragments in melanic Andisols are the product of grassland fires. The small difference between the reflectance values of the charcoal fragments in the Andisols and the grass charcoal is possibly derived from the fact that charcoal fragments with lower reflectance are more likely to be retained in the soil than fragments with higher reflectance values.     

北约旦地区降水侵蚀因子的近似估算研究

Despite being in arid and semi-arid areas, erosion is largely a result of infrequent but heavy rainfall events; therefore, rainfall erosivity data can be used as an indicator of potential erosion risks. The purpose of this study was to investigate the spatial distribution of annual rainfall erosivity in North Jordan. A simplified procedure was used to correlate erosivity factor R values in both the universal soil loss equation (USLE) and the revised universal soil loss equation (RUSLE) with annual rainfall amount or modified Fournier index (F_mod). Pluviometric data recorded at 18 weather stations covering North Jordan were used to predict R values. The annual values of erosivity ranged between 86-779 MJ mm ha^-1 h^-1 year^-1. The northwest regions of Jordan showed the highest annual erosivity values, while the northeastern regions showed the lowest annual erosivity values.     

浸提剂pH值对煤矸石和煤泥污染物浸出特性的影响研究

为了研究煤矿外排固体废物的污染特征及其潜在生态危害,采用6种不同pH值的浸提剂对贵州4个煤矿区的煤矸石、煤泥和原煤进行了振荡浸提试验,探讨了浸出液的pH、EC和Fe、Mn、Cu、Zn、Pb、Cd6种重金属含量随浸提剂pH值的变化规律。结果表明,随着浸提剂的pH值逐渐升高,浸出液的pH值也逐渐升高,其EC逐渐下降,当pH值大于4.0以后逐步趋于稳定;所有重金属在强酸性环境中浸出量较大,并随pH值的增大呈下降趋势,浸出液中Fe、Mn的浓度普遍较高。3类样品中,煤矸石在酸性条件下其重金属的潜在浸出能力强,环境污染风险大。     

Effects of gypsum slotting on the hydraulic properties of a red-brown earth

In situ measurements of unsaturated hydraulic conductivity (k) and sorptivity (S) were made on a transitional red-brown earth at two sites. The first site was a non-ameliorated soil (control). At the second site the soil had been modified by mixing the soil with gypsum to a depth of 0.4 m using a rotary digger (gypsum slot). Measurements were made using a disc permeameter (radius 100 mm) at the surface of both sites and at depths of 0.15, 0.4 and 0.6 m at the control site, at various potentials.

At the control site, the values of k and S decreased with depth and potential, except at the depth of 0.6 m. The range of S measured was within one order of magnitude. The values of k ranged over two orders of magnitude. The values of k and S measured for the surface horizon were similar to previous measurements by other workers. However, the values of k for the subsoil (0.4 and 0.6 m depth) were greater than previously published values. The values of k and S for the slot soil were intermediate between values for the surface horizon and subsoil of the control soil, and similar to the values at 0.15 m depth of the control soil.

The steady state infiltration rate into a slot was calculated using a model developed for vertical slot mulches and compared with values from previous infiltration experiments. The calculated and measured values of the steady state infiltration rate were in agreement. An equation was derived for predicting the increase in steady state infiltration rate, of a soil containing slots, from the slot depth and spacing. The slot width has only a small effect on the steady state infiltration rate. The maximum steady state infiltration rate occurs when the depth of the slot is 0.837 m. The relationship between the increase in the maximum steady state infiltration rate and the slot spacing is presented. This and the relationship between the increase in steady state infiltration rate, slot spacing and depth were used in examples to predict the increase in steady state infiltration rate for various slot spacings and dimensions.     

Development of Singlet Oxygen Absorption Capacity (SOAC) Assay Method. 3. Measurements of the SOAC Values for Phenolic Antioxidants

Measurements of the singlet oxygen ((1)O(2)) quenching rates (k(Q) (S)) and the relative singlet oxygen absortpion capacity (SOAC) values were performed for 16 phenolic antioxidants (tocopherol derivatives, ubiquinol-10, caffeic acids, and catechins) and vitamin C in ethanol/chloroform/D(2)O (50:50:1, v/v/v) solution at 35 °C. It has been clarified that the SOAC method is useful to evaluate the (1)O(2)-quenching activity of lipophilic and hydrophilic antioxidants having 5 orders of magnitude different rate constants from 1.38 × 10(10) M(-1) s(-1) for lycopene to 2.71 × 10(5) for ferulic acid. The logarithms of the k(Q) (S) and the SOAC values for phenolic antioxidants were found to correlate well with their peak oxidation potentials (E(p)); the antioxidants that have smaller E(p) values show higher reactivities. In previous works, measurements of the k(Q) (S) values for many phenolic antioxidants were performed in ethanol. Consequently, measurements of the k(Q) (S) and relative SOAC values were performed for eight carotenoids in ethanol to investigate the effect of solvent on the (1)O(2)-quenching rate. The k(Q) (S) values for phenolic antioxidants and carotenoids in ethanol were found to correlate linearly with the k(Q) (S) values in ethanol/chloroform/D(2)O solution with a gradient of 1.79, except for two catechins. As the relative rate constants (k(Q)(AO) (S)/k(Q)(α-Toc) (S)) of antioxidants (AO) are equal to the relative SOAC values, the SOAC values do not depend on the kinds of solvent used, if α-tocopherol is used as a standard compound. In fact, the SOAC values obtained for carotenoids in mixed solvent agreed well with the corresponding ones in ethanol.     

玉米品种多环境测试数据的最优相对转化方法

相对评价是农作物品种多环境测试的主要评价方式。该文设计了5种测试数据的相对转化方法,同时,提出标准差比值这一指标,用于判别相对转化方法的优劣,并根据8 a中国玉米品种区试数据进行了实证分析。结果表明：该文提出的5种试验数据相对转化方法,均可适用于不同观测性状,相对值信息量丰富、易于理解,并有助于进行多指标加权与作图分析。标准差比值可直接反映经不同方法转化后,相对值与品种遗传特征的接近程度,可用于多环境测试数据相对转化方法优劣的判别。对于大部分性状,最优的数据相对转化方法依次为：以组均值为参照系的3S和2S转化法>标准位次法>以组均值为参照系的类NDVI法>以对照值为参照系的类NDVI法>以对照值为参照系的3S和2S转化法>原始观测值。其中,以组均值为参照系的3S和2S转化值与遗传特征最为接近,可作为品种多环境测试数据的主要相对转化方法。     

Mineral Composition and Dry Mass Production of Corn Plants Affected by Different Phosphate Sources and Different Soil Aluminum Saturation Levels

Abstract

The effects of different commercial phosphate fertilizers [Triple superphosphate (TSP), Tricalcium phosphate (TCP), and ARAD rock phosphate) and soil aluminum (Al) saturation (86, 29, and 0%) on the mineral composition and dry mass production of corn (Zea mays) plants were studied. As soil Al saturation values decreased, pH, calcium (Ca), and magnesium (Mg) levels in the soil increased. High Ca values in the shoot resulted in the reduction in potassium (K) concentrations. The high values of P availability in the soil for the ARAD source of P did not correspond to the high values of dry mass production of corn plants. The high values of corn mass production were noticed for the TSP phosphate source, and the mass productions values were reduced as the soil Al saturation values increased.     

河北省生态系统服务价值变化研究

本研究分析了1993～2000年河北省土地利用和生态系统服务价值变化。结果表明,河北省耕地、水域、湿地和未利用土地面积在减少,而园地、林地、牧草地和建设用地面积在增加,因水域和湿地单位面积生态系统服务价值较高,7年间河北省区域生态系统服务价值显著减少,河北省生态系统服务价值从1993年的157.3116亿美元减少到2000年的152.3503亿美元,减少率为3.15%,净减少值4.9613亿美元。