Deficit irrigation based on drought tolerance and root signalling in potatoes and tomatoes

Agriculture is a big consumer of fresh water in competition with other sectors of the society. Within the EU-project SAFIR new water-saving irrigation strategies were developed based on pot, semi-field and field experiments with potatoes (Solanum tuberosum L.), fresh tomatoes (Lycopersicon esculentum Mill.) and processing tomatoes as model plants. From the pot and semi-field experiments an ABA production model was developed for potatoes to optimize the ABA signalling; this was obtained by modelling the optimal level of soil drying for ABA production before re-irrigation in a crop growth model. The field irrigation guidelines were developed under temperate (Denmark), Mediterranean (Greece, Italy) and continental (Serbia, China) climatic conditions during summer. The field investigations on processing tomatoes were undertaken only in the Po valley (North Italy) on fine, textured soil. The investigations from several studies showed that gradual soil drying imposed by deficit irrigation (DI) or partial root zone drying irrigation (PRD) induced hydraulic and chemical signals from the root system resulting in partial stomatal closure, an increase in photosynthetic water use efficiency, and a slight reduction in top vegetative growth. Further PRD increased N-mineralization significantly beyond that from DI, causing a stay-green effect late in the growing season. In field potato and tomato experiments the water-saving irrigation strategies DI and PRD were able to save about 20-30% of the water used in fully irrigated plants. PRD increased marketable yield in potatoes significantly by 15% due to improved tuber size distribution. PRD increased antioxidant content significantly by approximately 10% in both potatoes and fresh tomatoes. Under a high temperature regime, full irrigation (FI) should be undertaken, as was clear from field observations in tomatoes. For tomatoes full irrigation should be undertaken for cooling effects when the night/day average temperature >26.5 °C or when air temperature >40 °C to avoid flower-dropping. The temperature threshold for potatoes is not clear. From three-year field drip irrigation experiments we found that under the establishment phase, both potatoes and tomatoes should be fully irrigated; however, during the later phases deficit irrigation might be applied as outlined below without causing significant yield reduction:

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Potatoes

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After the end of tuber initiation, DI or PRD is applied at 70% of FI. During the last 14 days of the growth period, DI or PRD is applied at 50% of FI.

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Fresh tomatoes

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From the moment the 1st truce is developed, DI is applied at 85-80% of FI for two weeks. In the middle period, DI or PRD is applied at 70% of FI. During the last 14 days of the growth period, DI or PRD is applied at 50% of FI.

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Processing tomatoes

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From transplanting to fruit setting at 4th-5th cluster, the PRD and DI threshold for re-irrigation is when the plant-available soil water content (ASWC) equals 0.7 (soil water potential, Ψ_soil = −90 kPa). During the late fruit development/ripening stage, 10% of red fruits, the threshold for re-irrigation for DI is when ASWC = 0.5 (Ψ_soil = −185 kPa) and for PRD when ASWC (dry side) = 0.4 (Ψ_{soil, dry side} = −270 kPa).

The findings during the SAFIR project might be used as a framework for implementing water-saving deficit irrigation under different local soil and climatic conditions.     

土地整理项目管理与决策支持系统的构建

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密云水库及上游流域环境监测信息系统的设计与实现

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基于Web Services的农村小额贷款决策支持系统设计研究

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分布式人才管理决策支持系统的设计与实现

根据当前人才工程与现代科学人事制度需要，提出建立分布式多层人才管理决策支持系统作为管理科学化，民主化的有利保证，该系统综合利用ＷＷＷ技术、ＣＯＲＢＡ技术及ＯＬＥ／ＣＯＭ技术为广大分布用户提供分布决策支持；同时，为决策系统提供了集成一些新技术的有利手段；并且决策中定性推量和定量推理能够相辅相成协同完成多级决策技术。     

奶牛生产管理决策支持系统设计

本文主要探讨黑龙江垦区奶牛生产管理决策支持系统（ＣＰＭＤＳＳ）的设计思想和构建方法,介绍了ＣＰＭＤＳＳ数据库、模型库、方法库及人一机交互系统的功能特点和实现途径,为ＣＰＭＤＳＳ的实施开发打下基础。     

动态决策支持系统开发及其在油田生产中的应用

油田生产具有高投入、高产出、高风险的特点以及不可逆性,科学决策尤为重要。但已有的决策支持系统缺少信息综合应用、判断和自动决策的功能。针对以上问题,结合已有的决策支持系统以及油田实际生产情况,提出构建基于数据仓库的综合管理平台并引入专家系统的决策支持系统框架体系。综合管理平台集成现有的数据以及应用系统,通过XML进行动态数据交换,在此基础上构建数据仓库;专家系统通过推理机制为决策支持应用提供基于知识的专家意见。该系统在油田生产决策制定上起到了很好的辅助作用。     

WebPIPA （Web Based Paddy Irrigation Productivity Assessment）： An Online Irrigation Water Supply Management for Tanjung Karang Rice Irrigation Scheme （TAKRIS）

Irrigation water management has significant economic implications in developing countries like Malaysia. As in many countries, Malaysia is also espousing internet as a platform of new possibilities for information access and sharing. Thus web based decision tools are pertinent in managing water, which is becoming a source of conflict between domestic, industry and agricultural use in this emerging technological and information age. Decision Support System （DSS） created in the past was theoretically acceptable but practically not effective in the transfer of scientific knowledge from research labs to the end-users to support them in decision making. The Web Based Paddy Irrigation Productivity Assessment （WebPIPA） is an example of DSS created to provide an effective conduit for the transfer of scientific knowledge from research labs to the end-users to support them in decision making. WebPIPA serves as an innovative, user friendly and efficient management tool for run-of-river rice irrigation system. It is a web based program that requires users to login through user name and password WebPIPA is developed using Net framework and ASP. Net Programming Languages of Microsoft. Net 2003 environment. A 3-tier architecture framework was carefully studied and was implemented to create the WebP1PA model. Mathematical model developed for aiding irrigation decisions must be oriented towards addressing various issues in addition to the scientific ones for better acceptability. All government and private agencies, researchers, station users, farmers, investors and buyers related to this study area will be able to access and share the database through the internet. By strengthening the involvement of government departments, the database can be very effectively used by all stakeholders at the same time narrowing the gap between the urban and rural communities in the development of country.     

生态农业决策支持系统的建立

根据生态农业发展的需要，建立了生态农业决策支持系统。对生态农业决策支持系统的概念、设计思想、内容构成、结构及功能进行了分析。     

基于CGE模型的政策模拟系统的研究

针对目前政策模拟分析系统缺乏的问题,提出利用计算机技术将CGE模型、DSS、数据仓库、数据转换等集成在一个模拟系统中:采用Visual C .net开发模拟分析系统的人机交互界面和问题处理系统;GAMS IDE完成CGE模型生成和求解系统;数据仓库采用SQL Server 2000设计并实现,构造了政策模拟原型系统。在所设计的模拟系统上,以农业补贴政策模拟为例,通过情景分析法进行实证模拟分析。结果表明:模拟集成系统初步实现了CGE建模、模拟计算、系统维护及人机交互的功能。该模拟系统能够解决实际政策模拟问题,辅助决策者进行政策制定。