不同浓度NaCl处理对番茄果实生长、产量和品质的影响

番茄定植栽培在营养液槽中,采用不同浓度的NaCl进行盐胁迫处理试验。结果表明:盐胁迫抑制番茄植株株高和茎粗的生长,降低果实的横径与纵径长度;降低番茄的单株产量和单果重;但0.08mol.L-1和0.16mol.L-1 NaCl处理可以提高番茄果实中Vc、可溶性固形物及有机酸的含量,0.16mo.lL-1 NaCl处理可以提高番茄果实中可溶性糖的含量,盐胁迫处理使番茄的糖酸比降低。     

雾培对番茄植株生长、产量和品质的影响

以土壤栽培为对照,采用山崎番茄营养液配方研究了雾培对番茄的生长、产量和品质的影响。结果表明:雾培番茄植株长势旺盛,叶片叶绿素含量和净光合速率增加,每穗果的单果重和单株产量提高。而茎粗和单株结果数变化不大。此外,果实VC含量、可溶性糖含量与有机酸含量,以及糖酸比均下降,风味降低。这说明雾培可促进植株叶片光合作用的提高,并促进光合产物的运转,增加番茄果实产量,但不利于果实的品质的改善。     

不同基肥对日光温室土壤肥力、番茄产量和品质的影响

针对北京郊区日光温室中基肥施用状况,设计了长期施用秸秆有机肥、膨化鸡粪和缓释肥3个处理,对日光温室土壤肥力及番茄品质的影响进行测定。结果表明:秸秆有机肥处理土壤速效养分含量较高,土壤有机质含量在3个处理中表现最高,为32.0g.kg-1;长期施用膨化鸡粪土壤酸化快,土壤养分含量处于中等;缓释肥作为基肥施用,可加速土壤速效养分积累,但土壤有机质含量较低;从番茄果实品质结果看,秸秆有机肥处理果实中Vc、可溶性固形物、可溶性糖、游离氨基酸及糖酸比值分别为13.60μg.g-1、54.4mg.g-1、37.6mg.g-1、62.22μg.g-1、9.68,都显著高于其他两个处理。缓释肥处理的果实各种营养品质都不如有机肥处理果实含量高。实验还分析了土壤养分含量与番茄果实品质、产量的相关性,结果表明:土壤有机质、速效钾、全氮含量与果实中多项营养品质指标和产量呈极显著正相关。     

弱光对不同基因型辣椒坐果和果实品质的影响

在塑料拱棚中通过人工遮光模拟弱光环境(35%光强),研究了弱光对8个不同基因型辣椒坐果和果实品质的影响。结果表明:弱光下辣椒单株产量、坐果率、单株坐果数、果实硬度显著下降,可溶性固形物、维生素C和可溶性糖含量减少,但单果重、果形指数和果实含水量增加。弱光下辣椒果实叶绿素和类胡萝卜素含量增加,叶绿素a/b比值下降。不同甜椒(果实味甜)与辣椒(果实味辣)材料对弱光的适应性上存在差异。     

不同氮水平下钾营养对大棚番茄产量及品质的影响

在不同氨水平下钾营养对大棚无土栽培番茄产量及品质的影响结果表明适当提高钾肥浓度,可提高番茄坐果率、产量．以及果实中Vc含量、可溶性糖和有机酸含量,并且果实硝酸盐含量和筋腐果发生率明显降低。但钾肥浓度过高,会使番茄产量、品质降低。氮钾配施十分重要,本试验以N     

不同丛枝菌根真菌对番茄生长及相关生理因素的影响

对番茄中杂9号接种6种不同的丛枝菌根真菌(Glomus versiforme,Glomus mossea-2,Glomus intraradices,Glomus diuphauam,Glomus mossea,Glomus etuni-catum1),通过测定不同菌种对番茄的生长效应及叶片生理变化,表明不同丛枝菌根真菌对番茄有不同程度的生长促进作用,处理番茄的叶片可溶性糖、可溶性蛋白、硝酸还原酶(NR)活性均比对照有所增加,其中对叶片可溶性糖的影响最为显著,它与番茄根系的菌根侵染率呈极显著正相关,还与植株总干重显著正相关,菌根侵染率亦与植株干重显著正相关。故此提出叶片可溶性糖含量可作为丛枝菌根影响番茄生长的生理鉴定指标,依此指标筛选出Glomus versiforme,Glomusmossea-2是对番茄生长促进效果最好的菌种。     

不同水肥处理对辣椒保护地土壤温度和CO2含量的影响

研究了吉林省龙井地区保护地不同水、肥(氮、磷)处理对土壤温度、CO2含量的影响,结果表明:灌水量、土壤湿度与各个土层土壤温度之间呈显著的负相关,但是由于土壤水分影响到土壤升温和保温两方面,在相同施肥量下,其综合作用的结果是,以灌水定额为为2水平(118.33 m3hm-2次-1)处理的土温最高;灌水定额最大的4水平处理土温最低;土壤湿度、温度与土壤中CO2含量都呈极显著的正相关;低量氮肥和高量磷肥可使土壤中CO2含量增加;通过灌水、氮肥、磷肥的三因素四水平的水肥耦合实验研究发现,水、氮、磷处理均为3水平的处理辣椒产量最高;若在此处理水平上提高灌水量或施磷肥量都会使辣椒产量降低,而土壤中CO2含量却升高明显。     

不同灌溉方式和施肥处理对番茄氮素吸收及产量和品质的影响

以番茄为试材，研究了不同灌溉方式和施肥处理对番茄氮素吸收和产量品质的影响，结果表明：在模拟田间的盆栽条件下，滴灌较漫灌能够明显地增加番茄果实的干物重和果实的吸氮量，降低番茄果实中硝酸盐的含量；在磷钾肥基础上配施氮肥对果实的干物重及吸氮量没有明显的作用，但可以提高番茄Vc含量；配施有机肥可以促进果实的干物质积累和对氮素的吸收，同时有机肥也能够明显提高果实中的糖酸比，降低硝酸盐的含量。     

烯效唑(S3307)对葡萄果实着色及品质的影响

以京亚和夕阳红葡萄为试材,用不同浓度S3307喷施果穗,研究S3307对葡萄果实着色及品质的影响.实验结果表明S3307显著促进葡萄果皮花色素含量增加,使可溶性糖含量增加,有机酸含量下降,提高糖酸比,维生素C含量升高.这说明S3307有促进葡萄果实着色作用,并能改善果实品质,因此在生产上有一定应用价值.进一步研究表明,花色素含量与可溶性糖含量和糖酸比呈显著正相关,与有机酸含量呈显著的负相关.     

钴对番茄生长发育影响的初步研究

采用盆栽试验研究了钴对番茄生长发育及产量的影响,同时还研究了钴在番茄植株体内的分布情况和土壤中有效钴含量的变化状况。初步研究结果表明:钴能提高番茄植株功能叶片叶绿素含量、花蕾数和开花数、地上部分鲜重;而对植株的株高、复叶数和根重(AW)无显著影响。但钴对产量构成因素中的作用较明显,能显著提高坐果率、单株结果数和产量。钴在植株体内各部位的含量及土壤有效钴的含量均随施钴量的增加而显著增加。在本试验条件下,钴的最大处理(64mg kg-1土)未对番茄产生不良影响。     

Evaluation of hyperspectral indices for LAI estimation and discrimination of potato crop under different irrigation treatments

In this study, various hyperspectral indices were evaluated for estimation of leaf area index (LAI) and crop discrimination under different irrigation treatments. The study was conducted for potato crop using the spectral reflectance values measured by a hand‐held spectro‐radiometer. Three categories of hyperspectral indices, such as ratio/difference indices, multivariate indices and derivative based indices were computed. It was found that, among various band combinations for NDVI (normalized difference vegetation index) and SAVI (soil adjusted vegetation index), the band combination of the 780～680, produced highest correlation coefficient with LAI. Among all the forms of LAI and VI empirical relationships, the power and exponential equations had highest R ² and F values. Analysis of variance showed that, hyperspectral indices were found to be more efficient than the LAI to detect the differences among crops under different irrigation treatments. The discriminant analysis produced a set of five most optimum bands to discriminate the crops under three irrigation treatments.     

不同土壤层次供应水分和养分对玉米幼苗生长和吸收养分的影响

本试验模拟滴灌方法 ,在不同土壤层次进行灌水和施用氮磷养分的盆栽玉米试验 ,旨在探讨在不同土壤层次供应水分和养分对夏玉米幼苗生长、根系空间构型及玉米对养分吸收的影响。试验表明 :在土壤深层进行滴灌可以有效降低土面蒸发 ,提高水分和养分的利用效率 ,从而显著提高玉米幼苗的生长量 ;在不同层次施肥灌水 ,对玉米根系在土壤中的空间构型影响很大 ,进行深层滴灌可以极大促进根系在较深土壤中的发育 ;在不同土层施肥灌水对玉米幼苗吸收N、P、K三种养分的能力也有影响 ,深层施肥灌水提高了玉米对 3种养分的吸收量     

Irrigation control based on model predictive control (MPC): Formulation of theory and validation using weather forecast data and AQUACROP model

This research proposes A THEORETICAL FRAMEWORK based on model predictive control (MPC) for irrigation control to minimize both root zone soil moisture deficit (RZSMD) and irrigation amount under a limited water supply. We (i) investigate means to incorporate direct measurements to MPC (ii) introduce two Robust MPC techniques – Certainty Equivalence control (CE) and Disturbance Affine Feedback Control (DA) – to mitigate the uncertainty of weather forecasts, and (iii) provide conditions to obtain two important theoretical aspects of MPC – feasibility and stability – in the context of irrigation control. Our results show that system identification enables automation while incorporating direct measurements. Both DA and CE minimize RZSMD and irrigation amount under uncertain weather forecasts and always maintain soil moisture above wilting point subject to water availability. The theoretical results are compared against the model AQUACROP, weather data and forecasts from Shepparton, Australia. We also discuss the performance of Robust MPC under different water availability, soil, crop conditions. In general, MPC shows to be a promising tool for irrigation control.     

Irrigated area mapping in heterogeneous landscapes with MODIS time series,ground truth and census data,Krishna Basin,India

Diverse irrigated areas were mapped in the Krishna River Basin (258,912 km²), southern India, using an irrigated fraction approach and multiple ancillary data sources. Unsupervised classification of a monthly time series of net difference vegetation index (NDVI) images from the Moderate Resolution Imaging Spectrometer (MODIS) over January–December 2002 generated 40 classes. Nine generalized classes included five irrigated classes with distinct NDVI time signatures: continuous irrigation, double‐cropped, irrigated with low biomass, minor irrigation, and groundwater irrigation. Areas irrigated by surface water began greening 45 days after groundwater‐irrigated areas, which allowed separation of surface and groundwater irrigation in the classification. The fraction of each class area irrigated was determined using three different methods: ground truth data, a linear regression model calibrated to agricultural census data, and visual interpretation of Landsat TM imagery. Irrigated fractions determined by the three methods varied least for the double‐cropped irrigated class (0.62–0.79) and rangeland (0.00–0.02), and most for the minor irrigated class (0.06–0.43). Small irrigated patches (<0.1 km²) accounted for more irrigated area than all major surface water irrigated areas combined. The irrigated fractions of the minor and groundwater‐irrigated classes differed widely by method, suggesting that mapping patchy and small irrigated areas remains challenging, but comparison of multiple data sources improves confidence in the classification and highlights areas requiring more intensive fieldwork.     

灌区信息化建设发展现状及应对策略

灌区信息化的建设发展是提升灌区管理水平和提高灌溉效益的有效手段之一。针对灌区信息化建设发展不同阶段中存在问题进行归纳总结,分别对规划、建设和运行管理阶段信息化建设发展现状进行分析,对规划质量、建设水平、设备维护、人才队伍建设相关问题进行探讨,并对存在的问题提出应对策略以供灌区信息化建设及长期运行管理需要。     

A holistic generic integrated approach for irrigation,crop and field management: the SALTMED model

A successful water management scheme for irrigated crops requires an integrated approach that accounts for water, crop, soil and field management. Most existing models are designed for a specific irrigation system, specific process such as water and solute movement, infiltration, leaching or water uptake by plant roots or a combination of them. There is a shortage in models of a generic nature, models that can be used for a variety of irrigation systems, soil types, soil stratifications, crops and trees, water management strategies (blending or cyclic), leaching requirements and water quality. SALTMED model has been developed for such generic applications. The model employs established water and solute transport, evapotranspiration and crop water uptake equations. In this paper, the model has been run with five examples of applications for one growing season using data from the literature. The model successfully illustrated the effect of the irrigation system, the soil type, the salinity level of irrigation water on soil moisture and salinity distribution, leaching requirements, and crop yield in all cases. Due to the scarcity of data sets that are suitable for model testing over the complete growing season, where different processes are acting simultaneously, a follow up paper will show the results of the model tests using data being collected from two sites in Egypt and in Syria as a part of ongoing SALTMED project.     

基于模糊RBF神经网络算法的灌溉控制系统设计

对于一个农田占地面积大,灌溉用水量少的农业国而言,高效用水影响着农业的稳步发展;针对这一现象,提出一种基于模糊RBF神经网络的灌溉策略,将隐层的输出函数构成一组基来逼近目标函数,预测出灌溉的需水量,并用模糊控制计算出具体的灌溉时间;以山西省忻州地区种植的玉米利合328号为例,对气象条件、土壤条件以及作物特性进行分析,可以根据不同环境计算出灌溉时间;对大田采取高效、实时的灌溉策略,不仅可以提高灌溉用水的利用率,还可以为大田灌溉的发展奠定基础,增加了作物的产量。     

IRRIGATE: A dynamic integrated model combining a knowledge-based model and mechanistic biophysical models for border irrigation management

Water management practices in southern France (the Crau plain) need to be modified in order to ensure greater water use efficiency and less environmental damage while maintaining hay production levels. Farmers, water managers and policy makers have expressed the need for new methods to deal with these issues. We developed the biodecisional model IRRIGATE to test new irrigation schedules, new designs for water channels or fields and new distribution planning for a given water resource. IRRIGATE simulates the operation of a hay cropping system irrigated by flood irrigation and includes three main features: (i) border irrigation with various durations of irrigation events and various spatial orders of water distribution, (ii) species-rich grasslands highly sensitive to water deficit, (iii) interactions between irrigation and mowing. It is based on existing knowledge, adapted models and new modules based on experiments and survey data. It includes a rule-based model on the farm scale, simulating dynamically both irrigation and mowing management, and two biophysical models. The two biophysical models are a dynamic crop model on the field scale simulating plant and soil behaviour in relation to water supply, and a flood irrigation model on the border scale simulating an irrigation event according to plant and hydraulic parameters. Model outputs allow environmental (water supply, drainage), social (labour) and agronomic (yields, water productivity and irrigation efficiency) analyses of the performance of the cropping system. IRRIGATE was developed using firstly a conceptual framework describing the system modelled as three sub-systems (biophysical, technical, and decision) interacting within the farm. Then a component-based spatially explicit modelling based on the identification of the interactions between modules, the identification of temporal and spatial scales of modules and the re-use of previous models was used to develop the numerical model. An example of the use of the biodecisional model is presented showing the effects on a real farm of a severe water shortage in 2006.     

基于Java的农田节水灌溉监控系统的设计与实现

针对我国目前农村水费计收存在的不合理性,以及农田灌溉中的大漫灌浪费水资源问题,介绍了一种农田节水灌溉监控系统的实现技术,描述了系统的结构、监控中心的功能和实现方法;并应用Java技术设计了一套远程监控中心系统软件,该设计方案应用Java面向对象的技术,可方便地跨平台应用,具有较高的可扩展性。实践表明：该系统使用方便,并且能够满足各项性能指标要求,显示了Java技术在灌溉监控系统中广阔的应用前景。