Malarial impact of surface irrigation projects: A case study from Gujarat,India

Year-round irrigation and multiple cropping with paddy as a dominant crop in the monsoon months have given rise to an increase in the incidence of malaria over an 18-year period in the Mahi-Kadana Irrigation Project in Gujarat State, India. Further man-made disturbances such as over-irrigation, and lack of drainage have also compounded the problem. The remedies, apart from the conventional control and prevention measures, are better water management practices and continuous monitoring of the projects by an inter-disciplinary team which should include a public health administrator.     

Predicting the field characteristics of drip irrigation

The measurements of sorptivity and conductivity for the surface and subsurface Lavalette soil, as presented in the previous paper, are used here to infer the salient features of drip irrigation experiments. Good prediction of the size of the free-water pond was obtained via Wooding's equation. Reasonable success was achieved with application of Raats' solution for the steady radial and vertical profiles of water content. However the soil's drop-off in conductivity with depth probably contributed to the observation of a greater lateral spread of water than the capillarity of the surface soil could alone sustain. Nevertheless Raats' solution is shown to be easy to parameterise. It is potentially useful for predicting solute travel times away from drippers, at least in unstratified soils.     

膜沟灌溉入渗规律试验初报

膜沟灌溉是与地膜覆盖技术相结合的沟灌,它将带有渗水孔的地膜敷贴在灌水沟内形成膜沟,灌溉时水在沟内的膜上流动,并通过膜孔渗入土壤。针对膜沟灌溉的累积入渗量、湿润深度随入渗历时变化规律进行了研究。研制了膜沟灌溉入渗试验装置,针对2排3列膜孔布置方案进行了膜沟灌溉入渗试验,观测得到了不同入渗历时的累积入渗量和湿润深度。结果表明,累积入渗量与入渗历时之间的关系符合Kostiakov-Lewis模型,湿润深度随入渗历时的变化符合幂函数关系,因此可用该2个模型描述膜沟灌溉的入渗规律。     

不同灌溉条件下优质小麦的产量及品质性状表现

本文研究了十五期间育成的几个优质小麦品种(系)在不同灌水次数和灌水量条件下产量和主要品质所受的影响,结果表明:产量三因素和产量在二水处理的穗数、穗粒重、千粒重、产量较一水、三水处理高.蛋白质含量二水处理最高,其次是一水和三水处理;干面筋含量二水处理大于一水处理、一水处理大于三水处理;湿面筋含量一水条件下相对较高,其次是二水处理;沉降值一水条件下相对较高.由此得出,在有限的灌溉条件下,科学合理的灌溉是保证优质小麦品种高产优质的基本条件.     

不同基因型玉米不同播期单倍体诱导效果初步研究

利用Stock6和H02单倍体诱导系对不同基因型玉米、不同播期单倍体诱导效果进行了初步研究。结果表明:H02平均诱导率比Stock6高2.11%～2.17%;不同基因型玉米单倍体诱导率差异明显;夏播材料诱导率高于春播材料。     

Growth dynamics of winter wheat in the field with daily fertilization and irrigation

In a field experiment with fertilized and irrigated winter wheat the above-ground crop was sampled once a week. Phenological development, plant density and canopy height were recorded and the green surface areas of leaves, stems and ears were measured. Soil mineral nitrogen was sampled and the field climate monitored. There were four treatments. The daily irrigated/fertilized (IF) and daily irrigated (I) treatments were both irrigated by a drip-tube system. Liquid fertilizer was applied to IF following a logistic function according to calculated plant uptake. A total of 200 kg N ha⁻¹ was applied. Treatment I, control (C) and drought (D) were all fertilized once in spring with 200 kg N ha⁻¹. In treatment D transparent screens were used to divert rainwater. Dry matter production ranged between 1400 in D and 2352 g m⁻² in IF. The corresponding amount of nitrogen uptake ranged between 15.8 and 24.6 g m⁻². After harvest, soil mineral nitrogen was lowest in IF.
An increase in the availability of nitrogen and water enhanced total biomass production as well as grain yield and leaf area. The daily supply of nitrogen according to crop demand delayed nitrogen uptake and increased total uptake. The results suggest that when the nitrogen is supplied in accordance with crop demand, the efficiency with which the applied fertilizer is utilized increases and the risk for nitrogen leaching decreases.     

两种除草剂胁迫对皇冠草生理特性的影响

本文以沉水植物皇冠草为试验材料,研究了两种除草剂（乙草胺、氯嘧磺隆）胁迫对皇冠草的丙二醛（MDA）含量、超氧化物阴离子（O2-）﹑过氧化氢（H2O2）含量﹑超氧化物歧化酶(SOD)、过氧化物酶(POD)及过氧化氢酶(CAT)活性的影响。结果表明：MDA、O2-、H2O2、SOD、POD、CAT活性随胁迫浓度的增加而增加;乙草胺胁迫下的各项生理指标峰值都高于氯嘧磺隆。     

不同灌溉方式对杂交粳稻皖旱优1号产量和稻米品质的影响

以水旱兼用的早熟中粳杂交稻皖旱优1号为试验材料,研究不同灌溉方式对其产量及稻米品质的影响。结果表明：无水层灌溉与常规灌溉相比,株高变矮,穗长、有效穗数、穗总粒数和穗实粒数均增加,千粒重减小,2a增产分别为14.1%、8.2%。无水层灌溉的垩白粒率和垩白度均降低,胶稠度增加,糙米率、直链淀粉含量有增加趋势,粒长变长,粒宽变小,整精米率略有下降,对稻米品质总体上有所改善。     

不同供水条件下玉米耐旱生理特性比较

【研究目的】本试验研究玉米耐旱生理特性,为玉米耐旱品种选育提供依据。【方法】试验以玉米品种正大619、农大108为材料,分别在间隔4天、8天、12天、16天灌一次水的不同水分处理条件下,分析玉米叶片叶绿素、脯氨酸（Pro）、丙二醛（MDA）的含量及超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性。【结果】结果表明：随着水分胁迫程度加大,玉米叶片脯氨酸的含量、MDA含量和POD活性呈现不同程度的增加,而叶绿素含量和SOD活性则随着水分胁迫程度加大而降低。且敏感型品种农大108的变化明显强于抗旱型的正大619。【结论】脯氨酸（Pro）、丙二醛（MDA）的含量及超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性可以作为玉米耐旱品种选育参考。     

不同钙化剂对高钒渣酸浸提钒的影响

针对传统钒渣钠化焙烧-水浸提钒工艺的不足,确定对钒渣钙化焙烧-酸浸提钒进行研究。在理论分析的基础上,本研究以高钒渣为原料,研究了钙化焙烧-酸浸提钒过程中3种钙化剂(CaSO4、CaCO3、CaO)的焙烧机理以及对提钒效果的影响。研究结果表明：钒浸出率随焙烧温度的升高先增大后减小,且在1 450 K时达到最大值;钙化剂配比为100%CaSO4时提钒率最大;在目前实验室研究条件下,钒的浸出率最大可达93.53%。     

Comparison of genetically modified and conventionally derived herbicide tolerance in oilseed rape: A case study

Oilseed rape (Brassica napus) is animportant source of oils for industrial andfood processes. Agriculturally it is auseful break crop in cereal rotations butsuffers from competition from broad-leavedweeds that can be difficult to control. Toextend the range and efficacy of weedcontrol options, herbicide-tolerant oilseedrape cultivars have been developed throughboth conventional and transgenic geneticmodification processes. Here we compare thesuccess of these approaches and discuss theimplications of the new herbicide tolerancetraits in agricultural production ofoilseed rape. We conclude that the impactof HT traits on the agri-environment willbe dependent on the nature of the trait andthe management strategies under which it isemployed. We find no evidence that thetechnology used in the production of HTcultivars has any influence on theirperformance as crops. In fact transgenic HTcultivars are simpler to monitor foragricultural and environmental impact thanare conventional HT cultivars.     

不同果袋处理对红富士苹果贮藏生理的影响

研究了套5种类型果袋对红富士苹果(Malus domestica cv. Red Fuji Spur)低温(0℃)贮藏品质的影响,部分果袋进行早套袋(6月10号)和晚套袋(6月23号)两个处理。各种套袋果实的呼吸速率和失水率在贮藏的第一个月内逐步提高达到峰值,其中套塑膜袋果实的呼吸速率比套小林袋的高47%,同时伴随着可滴定酸、可溶性糖以及硬度的持续降低;随后的一个月内呼吸受到明显抑制,各种品质指标下降缓慢,但在其后的贮藏时间里呼吸速率再次缓慢上升。套塑膜袋的果实仍具有较强的呼吸,晚套袋的果实比早套袋的呼吸略高。贮藏结束时(120d)套小林袋红富士的可滴定酸和果实硬度分别为0.2087%、9.43kg/cm2,套塑膜袋的分别为0.1812%、8.12kg/cm2。综合贮藏过程中果实的呼吸、糖、酸、硬度等指标的变化结果可以看到,不同果袋以套塑膜袋的果实品质下降最大,套小林袋(KM-2)的果实品质下降最小,其次是双层内红袋、双层内黑袋,再次是双层内塑袋。     

不同密度对滴灌红籽瓜产量及相关性状的影响

通过对滴灌红籽瓜不同密度对比试验寻找其适合大型机械化作业的最佳密度,从而进一步探讨红籽瓜高产栽培技术,为指导大田生产服务。采用扩大行距,对留苗方式进行必要的调整,分别对3700、5550、7400株/667m²三种密度做了小区试验。结果以5550株/667m²取得了较高的产量和较好的品质。在此密度下单产达147.8 kg,达极显著水平。总结出适合新疆昌吉地区红籽瓜高产栽培的最佳密度为5550株/667 m²,其产量、植株生长、主要经济性状、干物质积累为最佳。     

Life Cycle Analysis of field production of fibre hemp, the effect of production practices on environmental impacts

Summary Life Cycle Assessment (LCA) was used to assess the environmental impacts of field production of fibre hemp and seven other crops in France. The production of 1 ha of hemp yielded a eutrophication potential of 20.5 kg PO₄-equivalents, a global warming potential of 2330 kg CO₂-equivalents, an acidification potential of 9.8 kg SO₂-equivalents, a terrestrial ecotoxicity potential of 2.3 kg 1,4-dichlorobenzene-equivalents, an energy use of 11.4 GJ, and a land use of 1.02 ha.year. A comparison of hemp (low impacts), wheat (intermediate impacts) and sugar beet (high impacts) revealed that the crops were similar for the relative contributions of emitted substances and resources used to impacts, and for the relative contribution of processes to impacts. A reduction of the impacts of hemp production should focus on eutrophication, and consider the reduction of climate change, acidification and energy use as secondary objectives. Given this objective, the overall environmental effect of the substitution of mineral fertiliser by pig slurry is negative. The introduction of reduced tillage is of interest, as it decreases energy use, acidification and climate change. Measures leading to a reduction in NO₃ leaching are highly interesting, as they strongly decrease eutrophication. Implications for hemp breeding are discussed.     

Experiments on the invasion impact of penetrant solution with different concentrations on gas desorption

It’s proved for the first time that external solution can promote gas desorption by using independently designed gas desorption measuring device. Two reasons of competed adsorption location between liquid and gas and capillary static driver are analyzed. The result shows that the gas desorption efficiency increases as the concentration of penetrant solution increases and the promotion effect of penetrant solution only occurs in a period of time. Then specific measurements of improving gas desorption efficiency on coal face are proposed. The study can provide reference for solving the time constraint between gas extraction and mining on coal face.     

不同灌溉条件下冠菌素对大豆光合特性与产量的调控效应

干旱是限制大豆丰产稳产的重要因素之一,利用生物调节剂提高大豆耐旱性是生产中一种新型的生物节水管理模式。本研究在常规灌溉与无灌溉条件下,采用生物调节剂冠菌素(COR)于大豆初花期进行叶面喷施处理,研究COR对植株农艺性状、叶片水势和光合特征、产量及其构成因素的调控效应。试验结果表明:在正常灌溉条件下, COR处理对大豆叶片水势、叶绿素含量、光合速率、叶绿素荧光参数、RuBP羧化酶和SPS活性等影响较小,与对照相比其产量和生物量差异不显著。但在生长季无灌溉的雨养条件下,COR处理会显著提高大豆开花后叶片水势、叶绿素含量、光合速率和叶绿素荧光参数,增加叶片RuBP羧化酶和SPS活性,改善大豆产量构成因素,最终导致籽粒产量增加。总之,在雨养条件下, COR对大豆光合特征和产量形成具有积极的调控效应。     

Analysis of maize growth for different irrigation strategies in northeastern Spain

Water availability is the key factor determining maize yields in NE Spain. Irrigation is needed to obtain economic yields but it is costly and water supply is sometimes insufficient. The aim of this research was to test a simple simulation model for evaluating different irrigation strategies, especially under water-limited conditions. The LINTUL model was adapted and parameterized using experimental data from the 1995 season. Most parameters were obtained from experiments, although some were taken from the literature. This model is based on the concept of light use efficiency, incorporates a soil water balance and simulates phenology, crop leaf area, biomass accumulation and yield. It was tested on independent data from the 1995 and 1996 seasons under different irrigation treatments. The model predicted the flowering date within ±5 days of the observed values. Leaf area index was predicted satisfactorily, except under extreme water-stress conditions, where it was overestimated. In general, soil moisture content and yield were accurately predicted. In the 1996 experiment measured yields ranged from 6.4 to 13.6 t ha⁻¹ and simulated yields from 6.5 to 12.2 t ha⁻¹. These results show that the LINTUL model can be used as a tool for exploring the consequences on maize yields of different irrigation strategies in NE Spain. Analysis of the model identified a process that strongly affects yield loss due to drought, but for which present understanding is still insufficient: the effects of drought on leaf senescence and canopy architecture.     

不同灌水模式下罂粟吗啡含量的变化

本文初步探讨了水分调控对罂粟不同生育时期地上主要器官吗啡含量的影响,实验结果表明,冬灌区现蕾期到盛花前期,随着灌水频率加大,罂粟壳中吗啡含量明显提高,盛花后期的连续灌水使罂粟壳中吗啡含量急剧下降,免冬灌区恰好相反,发育后期适当加大灌水频率和提高灌水量能明显的提高罂粟壳中的吗啡含量     

Estimation of the year-to-year variations in nitrate leaching in different soils and regions of England and Wales

A model has been used to estimate the losses of N by leaching from arable soils throughout England and Wales during winter and spring. It is predicted that the extent to which autumn residues of nitrate are leached by winter rains varies considerably from year to year and from site to site, and that this variation will cause much bigger differences in the N fertilizer requirements of deep-rooted crops than of shallow-rooted ones. It is estimated that an average of about 42% of the N applied as fertilizer is leached from arable soils in England and Wales each year. However, the resulting increase in the average nitrate concentration in the drainage water is estimated to exceed 11.3 μg N/ml only in the Eastern region. Spring leaching of freshly-applied N fertilizer is likely to be generally small, and will have little effect on the N fertilizer requirements of deep-rooted crops, but may affect those of shallow-rooted crops in the west.