三门峡水库库岸坍塌成因分析与防治措施研究

三门峡水库自1960年9月蓄水运行以来,库岸坍塌现象频繁发生,平均每年塌岸0.5～0.7亿m3.指出了造成库岸坍塌的原因主要是地质环境的影响以及水力条件的变化;不同的地形、地貌、地质结构和岩性特征,表现了不同的塌岸强度,其中黄土塬区为极强塌岸段,黄河Ⅱ级阶地为强烈塌岸段,黄河Ⅰ级阶地为中等强烈塌岸段;分析了引起库岸坍塌的主要水力条件有大气降水、地表水和地下水,并且不同水力条件及其变化特征,对库岸坍塌影响的方式和程度也不同;最后给出了防治库岸坍塌应采用标本兼治的原则,治标是指对塌岸进行必要的加固、支挡、衬砌等;治本就是根据引起塌岸的原因以及不同地质环境条件下的塌岸特征和水力条件,因地制宜,因害设防,从根本上进行综合治理.     

Monitoring of the humus status of soils of the Ingulets irrigation system

The results of long-term studies (1957–2007) of the changes in the morphology of soil profiles and in the reserves and fractional composition of the humus in the soils of the Ingulets irrigation system are discussed. After 50 years of irrigation, the boundaries of the genetic horizons shifted downward by 15–30 cm. The redistribution of the humus took place: its content decreased to a low level in the plow layer of the irrigated and rainfed soils and significantly increased in the layer of 60–100 cm so that the reserves of humus in the layer of 0–100 cm somewhat increased and corresponded to a moderate level. The distribution of humus in the soil profiles was characterized by the gradual lowering down the soil profile. The concentration of nitrogen in the humus of the irrigated southern chernozems was very low. The degree of humification of the soil organic matter was high. The humus was of the humate type in the upper horizons and of the fulvate-humate type in the lower horizons.     

降低UV-B辐射强度对小麦类黄酮含量及分布的影响

在降低目前南京地区近地面UV—B辐射强度的条件下,研究了小麦叶片类黄酮含量及分布的变化。试验结果表明：UV—B紫外辐射强度降低,类黄酮含量显著下降,拔节—孕穗期最为敏感;小麦上部叶片类黄酮含量变化显著大于中、下部叶片,在单张叶片中,叶片基部类黄酮含量显著较叶片尖、中部低。UV—B紫外辐射强度降低,小麦叶片叶绿素含量增加。     

Development of hydromorphism in soils of agrolandscapes in the depressions of Western Ciscaucasia

The current state and rate of hydromorphism development in the soils of flat bottomed depressions in Western Ciscaucasia are assessed. The dynamics of the soil cover pattern on a plain with numerous mesoand microdepressions and on a watershed with weakly pronounced erosion relief were revealed. The relationship between the expansion of the waterlogged areas and the pattern of the soil cover of the agrolandscapes in the depressions was revealed. The dependence of the areas of excessively moistened sites on the changes in the topography was shown. The direction and parameters of the changes in the morphology, chemical composition, and hydrological properties of the degraded hydromorphic soils were investigated. The relationships between the density of the soils and the humus content and the composition of the exchangeable bases were studied. Methods for the assessment of the rates of the degradation processes based on the comparison of aerial photographs and soil maps for typical sites in the territory investigated are proposed. The specific features of decoding the aerial photographs of the soils in the depressions were revealed. The relations between the differences in the photos’ tone and the degree of the hydromorphic degradation of the soils were found. Promising methods for interpretation of aerial photographs with the help of image analysis programs can be recommended.     

不同施肥处理对莴笋营养效应的研究

采用田间试验研究了不同施肥处理对莴笋产量、品质和经济效益的影响。结果表明,在CK(N15P5K10)基础上分别增施氮肥、磷肥、钾肥、硼肥或有机肥可使莴笋增产19.4%~66.4%,以施用有机肥菜籽粕增产作用最大。有机肥泥炭和菜籽粕处理使莴笋茎硝酸盐含量分别降低9.3%和18.0%。不同施肥处理均提高了莴笋叶和茎维生素C含量,菜籽粕处理莴笋叶维生素C含量增幅最大(为16.5%),泥炭和菜籽粕处理莴笋茎维生素C含量均显著高于其他处理。增施钾肥处理对提高莴笋叶还原糖含量作用最大(达10.0%),增施磷肥处理对提高莴笋茎还原糖含量效果显著。不同施肥处理均提高了莴笋叶必需氨基酸含量,硼肥( B)处理莴笋叶蛋氨酸/亮氨酸比值最高;泥炭处理对提高莴笋茎蛋氨酸/亮氨酸比值及甜味、鲜味氨基酸占氨基酸总量的比例效果最佳。菜籽粕处理莴笋施肥利润最高,增施钾肥处理产投比高于其他处理。     

永磁式缓速器转子鼓的瞬态温度场分析

该文运用传热学原理建立了车用永磁式缓速器转子鼓瞬态温度场的计算模型,确定了合理的边界条件,同时考虑了对流换热和辐射换热。利用Galerkin法推导温度场的有限元方程,采用无条件稳定的Galerkin格式离散时间微分项,迭代控制采用新型的变时间步长法,分析了转子鼓的瞬态温度场,同时分析了径向和轴向方向的温度与时间的分布规律,并对轴向温度分布进行了试验研究,结果表明试验值与采用有限元计算的理论值吻合较好。采用温度场分析可以优化转子鼓设计,减小转子鼓温度和温度梯度,从而降低转子鼓的热应力与热变形,有效地提高了永磁式缓速器的制动稳定性。     

Priority organic pollutants in soil of arboretum of the Botanical Garden of Moscow State University: Report 3. Specific features of vertical distribution pattern of organochlorine pesticide in profile of urbanozem

The vertical distribution pattern of dichlorodiphenyltrichloroethane (DDT) and its metabolites (hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB)) in the urbanozem of the arboretum of the Botanical Garden of Moscow State University at Vorob’evy Gory is studied. The highest contents of DDT, dichlorodiphenyldichloroethylene (DDE), and HCH isomers in the soil profile are found in the Au humus horizon and/or in the top part of the U technogenic 10–20-cm-thick layer. The greatest HCB content is typical of the U technogenic 20–30-cm-thick layer. The total content of DDT and its metabolites (156.2 mg/kg) in the surface layer is within the range typical of soils of old parks and recreational zones. The residual DDT content in the soil profile is 0.336–1.47 of the maximum permissible content. The ratio between metabolites and isomers of DDT points to its slight transformation (5.67–37.6%) and application as an industrial chemical. The contents of HCB (2.479–5.868 μg/kg) and the total content of HCH isomers (α + β + γ) in the profile of the urbanozem are 1–2 orders of magnitude lower than the maximum permissible contents or approximate permissible contents (0.3824–0.9863 μu/kg) and correspond to their background levels. The ratio between the HCH isomers shows that the transformation rate of the pesticide is rather high and that in the preceding period it was mainly used in the form of lindane.     

外源植酸酶对土壤有机磷组分含量的影响

采用室内培养的方法,研究了不同用量外源植酸酶在不同培养时期对土壤有机磷组分及数量的影响。结果表明,添加外源植酸酶各处理在各培养时期土壤活性和中等活性有机磷的含量和比例均高于对照,各处理间呈极高量>高量>中量>低量>对照,其含量随培养时间的延长呈增加趋势,至培养第40 d达最高值;而中稳性和高稳性有机磷含量均低于对照,各处理间呈极高量<高量<中量<低量<对照,其含量随培养时间的延长呈减少趋势,至培养第40 d达最低值;添加外源植酸酶各处理的有机磷总量均低于对照,并随植酸酶添加量的增加而减小。外源植酸酶可以促进土壤稳定性有机磷向活性有机磷转化,乃至向无机磷转化,从而提高了土壤有机磷素的有效性。     

农艺措施和施肥对渭北旱塬旱地玉米的影响

2002—2003年在渭北旱塬（陕西省铜川市）进行了不同农艺措施和施肥条件下玉米地土壤墒情、玉米生长和产量试验。结果显示,覆盖、垄沟等措施都能够在一定程度上提高土壤水分含量,但降水量和降水时间分布特点对土壤墒情的影响更大。同常规种植的玉米相比,覆盖、垄沟和施抗旱专用肥等技术措施有利于玉米生长。渭北旱塬区玉米产量一般在7000kg·hm^-2左右,但不同处理间玉米产量存在较大的差异,其中以有地膜覆盖的处理增产效果最为明显,一般较常规种植增加35％～43％。比较2a的试验结果还发现农艺措施的效果与降水年型有关,在较干旱年份,地膜覆盖、垄沟和施抗旱专用肥等技术措施的增产效果更明显,玉米产量能够提高10％-15％。     

Effect of convection on the exchange coefficient of oxygen and estimation of net production rate of oxygen in ponded water of a paddy field

Abstract

Dissolved oxygen (DO) in ponded water is essential to biological activities in paddy fields. DO concentrations results from the balance among photosynthesis, respiration, and exchange of oxygen between the atmosphere and water, all of which show daily changes. For the estimation of the net production rate of oxygen that is the overall response of photosynthesis and respiration, it is necessary to determine the exchange rate of oxygen between the atmosphere and water. The exchange of oxygen occurs in the form of reaeration and deaeration in the paddy fields. The exchange coefficients of reaeration and deaeration were determined in the laboratory considering field conditions. The coefficients of reaeration and deaeration were not identical. Both coefficients increased as the convective velocity in the water increased. It was considered that the convection in bulk water reduced the thickness of the water film at the air-water interface and increased the exchange coefficient. The reaeration and de aeration coefficients ranged from 2.1 to 2.4 and 5.7 to 6.3 d^?1, respectively. The rates of reaeration and de aeration were estimated using these exchange coefficients. The exchange rate was not constant in the paddy field throughout the day but varied with the convection, water temperature, and the degree of saturation in the ponded water. Taking these factors into consideration, the net production rate was estimated from the DO mass balance. The net production rate was positive from 5 : 30 to 15 : 30 and negative in the other part of the day. These results and analytical methods would contribute to the understanding of the physical, chemical, and biological processes in a paddy field.     

上海市郊林带的防风效应分析

用夏季台风影响期间上海市东南沿海南汇海塘边林带防风观测资料和冬季冷空气影响时北面嘉定浏岛林带防风观测资料分析上海市郊林带的防风效应。结果表明：无论是夏季台风还是冬季冷空气影响时，林带的防风效应是非常明显的。台风影响期间，离林带越近，减风效应越大，随高度增加，减风效果减小；而远离林带处的减风率较小，随高度升高，减风效果增大；而且林带的减风效应还与风速有关，风速越小减风效果越明显。冬季由于受两条交叉林带的影响，两个测点的防风效应基本一致。试验结果可为上海市郊林带布局提供参考。     

Assessment of the state of urban ecosystems on the basis of remote sensing data

The results of the soil-ecological monitoring of the Novovladykino (Moscow) key site are presented. The monitoring included the interpretation of aerospace information collected in 2000 and 2010, terrestrial route observations, and mapping of the key site. The data obtained confirm the possibility to use the remote sensing information in the investigation of urban ecosystems and to recognize the arboreal vegetation, shrubs, and lawn grass in images. The approximate identification of the tree species; the assessment of the state of the green belts and the natural, anthropogenic, and technogenic soils and their complexes; the identification of the overcompacted, mechanically destroyed, and sealed soils under the waterproof and permeable surface horizons are also possible. The determination of the species composition of the trees in small groups, the poor state of the individual trees and small groves, and the causes of the changes in the state of the green belts and polluted areas turned out to be impossible. Additional field and laboratory investigations were performed in order to verify and refine information obtained from the satellite images.     

Assessment of the mobility and time of renewal of the densimetric fractions of organic matter in chestnut soils from the ratio of stable carbon isotopes

The results of experimental studying of the organic matter status in soils using methods of granulodensimetric fractionation and the geochemistry of the stable carbon and nitrogen isotopes are presented. The organic and organomineral matter in chestnut soils representing a chronoseries—stages of natural changes in the vegetation with different carbon isotope compositions—were investigated. The organomineral fractions and fractions of free organic matter were distinguished, the changes in their proportion due to the changes in the vegetation were analyzed, and the residence time of the carbon in the organic matter of the fractions was assessed.     

中国荒漠化的形成原因和分布特征

 世界上的沙漠主要分布在副热带,唯独我国的沙漠分布在温带。根据有关文献和1994年我国沙漠化普查资料,介绍国内外现代干旱和沙漠化现状,分析青藏高原隆升、末次大冰期、水土资源分布、气候变化、社会经济干旱和人类不合理经济活动对我国北方沙漠化形成和分布的影响,以及未来发展趋势。建议要尽快实施跨流域调水、节水林牧业和依法治沙,彻底改变“三北”地区的干旱荒漠面貌。     

黄河上游北川河流域种子植物的区系特征

 北川河流域位居黄河上游地区,生态地位十分重要。流域内有种子植物74科、357属、1006种(含变种、变型)。流域内种子植物区系地理成分复杂多样,种子植物属有12个分布区类型和14个变型,与中国种子植物属的15个分布区类型、31个变型相比,分别占到80．0％和45．2％,类型较为齐全,变型也相当丰富。温带分布的属数及其所占的比例,在该区各分布类型中具有明显优势,其中尤以北温带分布类型更为显著,计有117属,占本区种子植物总属数的32．8％,占全国该类型分布的54．9％。该区植物区系的基本性质是以北温带为主。区系分区归属于泛北极植物区青藏高原植物亚区唐古特地区。植物区系成分的研究,为合理开发、利用、保护当地植物资源,开展科学引种提供了充分的依据。     

宁夏不同地区农田土壤磷素养分的空间变异特征

在宁夏灌区和旱区30块农田分别采集了0~120 cm深土壤剖面样品,测定了土壤全磷和速效磷含量,分析了土壤磷素养分含量的空间变异性。结果表明,在0~120 cm深土壤剖面中的全磷和速效磷含量,灌区土壤显著高于旱区土壤,在剖面点之间和土壤层次之间存在极显著差异,而且在土层间还存在着正相关。其变异系数总体上是旱区土壤大于灌区土壤,速效磷大于全磷。从地区来看,旱区土壤全磷和速效磷含量的变异系数随剖面深度的增加而增大,灌区土壤全磷量的变异系数在剖面层次之间差别不大,而速效磷的变异系数随剖面深度的增加而呈降低趋势。在0~120 cm深土壤剖面中,土壤全磷和速效磷的累积量灌区较旱区分别高出26.8%和65.0%,在土类间也存在较大差异。     

川东北季节性干旱区玉米的气候优势分区

在分析川东北地区玉米气候资源、季节性干旱特征、气候生产潜力的基础上,选择伏旱频率、3—8月日照时数、平均温度、温度日较差、光温生产潜力、气候生产潜力等因素作为指标因子,通过统计分析,建立各指标因子的空间分布模型;采用GIS分析技术,利用集优法将川东北季节性干旱区划分为5类玉米气候优势区。结果表明,川东北地区玉米气候综合优势的区域分布具有明显的带状特征,最优区在达州市、巴中市北部海拔较高的区域,相对较差的区域在广安、南充的南部地区。玉米气候优势分区结果可为川东北地区玉米生产布局调整和部分稻田水改旱提供科学依据。     

不同氮肥用量对石榴果实产量和品质的影响

以‘秋艳’石榴为试验材料,研究了不同氮肥用量对其果实产量和品质的影响。结果表明,施用氮肥可显著提高石榴果实产量,适量施用氮肥可增加石榴果实可溶性固形物、Vc、糖含量,降低石榴果实酸含量,提高石榴果实糖酸比,改善石榴果实的风味;施用氮肥对石榴百粒重、籽粒硬度无显著影响;石榴籽氮元素含量高于石榴皮,石榴汁中氮含量很低,中高氮处理的石榴汁中氮元素含量显著降低,石榴皮和石榴籽中氮元素含量变化不显著;本试验5年生石榴树纯氮施肥用量宜以0.4 kg·株~(-1)为宜。     

漂浮系统热量状况及对烟苗素质的影响

漂浮系统的温度主要受膜外大气温度制约，地温对其影响程度相对较低，表现为膜内空气温度、水温、底膜下温度低于常规苗床的对应温度，但由于育苗材料的不同，漂浮系统床面温度却高于常规苗床，特别是苗期后段时间，床面温度上升速度明显加快。漂浮系统育苗表现出前期幼苗生长缓慢，后期生长速度明显加速，幼苗素质最终明显好于常规苗的特点。     

西北地区夏季降水的气候特征分析

利用西北地区119站1961-2000年夏季（6-8月）降水资料，统计分析了各站历年夏季降水的平均场、方差场和各年代际平均值分布特征与整体总量逐年平均值的年际和周期变化特点，结果表明：西北地区夏季降水可划分为3个基本气候分区，即北疆区、中西部盆地沙漠区和东部季风影响区。中西部盆地沙漠区降水量和降水量方差均最小，处于稳定的干旱状态；东部季风影响区降水量的方差变化较大，降水的不稳定性增加，干旱频率增大；北疆区降水量较大，变差处于另外两区之间，表明旱涝影响微弱。各区的降水量在不同年代际间也具有不同的特点，降水量的变化会直接影响到当地主要旱地作物的产量。