Soil-Plant-Water Dynamics and Water Productivity Benefits of Subsurface Drip Irrigation

地下滴灌的土壤-植物-水动力学和水生产力效益

• 批准号: RGPIN-2014-04286
• 负责人: Madramootoo, Chandra
• 金额: $ 1.75万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=658402
• 关键词: Soil; Plant; Water; Dynamics; Productivity

An innovative five year research program is to be undertaken, aimed at investigating the potential efficacy and benefits of subsurface drip irrigation (SDI) for intensive vegetable production in Eastern Canada. Our hypothesis is that SDI has a superior water use efficiency compared to surface drip and overhead sprinkler irrigation systems, and if properly designed could reduce nutrient leaching below the root zone. There are currently no design criteria on the optimum depth of placement of the drip lines below the soil surface, and the optimum amount of water to be applied, to achieve maximum crop yields, for both mineral and organic soils in Eastern Canada. The research combines field, greenhouse and computer modeling studies.**Field studies will be conducted on a mineral soil at the McGill University Horticulture Research Station, and on an organic soil, 100 km south of Montreal, where vegetables are intensively cultivated. Using sweet bell pepper (Capsicum annuum. L) and tomato (S. lycopersicum) as test crops at both sites, drip irrigation lines will be installed at 20 and 30 cm below the soil surface, resulting in two SDI treatments. Drip lines installed on the soil surface will serve as a control. Three soil water replenishment levels (100%, 70% and 50% of field capacity - representing 3 levels of crop water stress) will be applied to the two SDI and the DI treatments, resulting in 9 treatment combinations, which will be statistically replicated. Several parameters including crop yield and marketable harvest, rainfall, evapotranspiration, irrigation applications, and soil moisture will be measured. Pore water samples will be collected from suction lysimeters in the 9 treatment combinations after each fertigation, and analyzed for nitrite, nitrate, and ammonia. This data will inform decisions about the appropriate depth of placement of the SDI lines below the soil surface, for optimum water savings and crop yields, and reduced nutrient leaching on mineral and organic soils.**Additionally crop-microclimate parameters (canopy temperature, stomatal conductance, leaf chlorophyll content, and photosynthetically active radiation) will be measured, and used to develop a Crop Water Stress Index (CWSI) for each water stressed condition for both SDI and DI. This data will result in a new technique for irrigation scheduling based on crop indicators, rather than on traditional soil moisture measurements. Furthermore, the CWSI, water savings and crop yield data will enable the development of an innovative crop-water productivity model for Eastern Canada. A greenhouse study with the 2 test crops, coupled with a computer simulation study using HYDRUS-2D, will permit a detailed assessment of soil moisture distribution under the two SDI treatments for both mineral and organic soils. The computer modeling will enable the derivation of SDI design criteria (depth of installation and emitter spacing) for a range of soils and environmental conditions. * *The research brings new findings on SDI, irrigation of organic soils, CWSI and crop-water productivity modeling to Canada and the scientific and engineering communities. Crop producers, irrigators and water managers who are faced with water scarcity due to competing water demands and climate variability, and rising water costs will benefit from the research findings. The sustainability and competitiveness of the Canadian fruit and vegetable industry, worth $1.5 billion annually, will be further enhanced by adoption of the research results. Five graduate students and several undergraduate students at McGill University will be trained under the project, thereby contributing to the development of highly skilled personnel for the irrigation and agricultural sectors.

将进行一项创新的五年研究计划，旨在调查加拿大东部的强化蔬菜生产的地下滴灌（SDI）的潜在功效和好处。我们的假设是，与表面滴水和架空洒水灌溉系统相比，SDI具有优异的用水效率，并且设计正确，可以减少在根区域以下的营养浸出。 目前，对于加拿大东部的矿物质和有机土壤，在土壤表面以下滴水线的最佳深度以及要施加的最佳水量的最佳水量尚无设计标准。 该研究结合了田间，温室和计算机建模研究。在两个地点，使用甜钟胡椒（Capsicumannuum。L）和番茄（S. lycopersicum）作为测试作物，将滴灌线安装在土壤表面以下20和30 cm的位置，从而进行两种SDI处理。安装在土壤表面上的滴水线将用作控制。三个土壤水补给水平（100％，70％和50％的田间容量 - 代表3个水平水应力）将应用于两种SDI和DI处理，从而产生9种治疗组合，这将是统计重复的。将测量几个参数，包括作物产量和可销售收获，降雨，蒸散量，灌溉应用和土壤水分。每种施肥后，将从9个治疗组合中的吸入溶液计收集孔隙水样品，并分析亚硝酸盐，硝酸盐和氨。该数据将为决策提供有关土壤表面下SDI线的适当放置的决定，以节省最佳的节水和作物产量，并减少在矿物和有机土壤上的养分浸出。对于SDI和DI的每个水应力条件。 这些数据将为基于作物指标而不是传统的土壤水分测量结果提供一种用于灌溉调度的新技术。此外，CWSI，节省水和作物产量数据将使加拿大东部的创新作物生产力模型开发。一项对两种测试作物的温室研究，再加上使用Hydrus-2D的计算机模拟研究，将允许对两种SDI处理的矿物和有机土壤的SDI处理下的土壤水分分布进行详细评估。计算机建模将使SDI设计标准（安装深度和发射极间距）为各种土壤和环境条件的推导。 * *该研究为加拿大以及科学和工程社区提供了有关SDI，有机土壤，CWSI和作物生产力建模的新发现。由于水的需求和气候变异性而面临水资源稀缺的作物生产商，灌溉者和水管理人员，以及水成本上升将从研究结果中受益。每年价值15亿加元的加拿大水果和蔬菜行业的可持续性和竞争力将通过采用研究结果进一步提高。麦吉尔大学的五名研究生和几名本科生将接受该项目的培训，从而为灌溉和农业领域的高技能人员发展做出了贡献。