New Strategy for Optimizing Water Application under Trickle Irrigation
نویسندگان
چکیده
The determination of water application parameters for creating an optimal soil moisture profile represents a complex nonlinear optimization problem which renders traditional optimization into a cumbersome procedure. For this reason, an alternative methodology is proposed which combines a numerical subsurface flow model and artificial neural networks ~ANN! for solving the problem in two, fully separate steps. The first step employs the flow model for calculating a large number of wetting profiles ~output!, obtained from a systematic variation of both water application and initial soil moisture ~input!. The resulting matrix of corresponding input/output values is used for training the ANN. The second step, the application of the fully trained ANN, then provides the irrigation parameters which range from a specified initial soil moisture to a desired crop-specific soil moisture profile. In order to avoid substantial disadvantages associated with the common feedforward backpropagation approach, a self-organizing topological feature map is implemented to perform this task. After a comprehensive sensitivity analysis, the new methodology is applied to the outcome of an irrigation experiment. The convincing results recommend the new methodology as a positive contribution towards an improved irrigation efficiency. DOI: 10.1061/~ASCE!0733-9437~2002!128:5~287! CE Database keywords: Trickle irrigation; Optimization; Neural networks.
منابع مشابه
بررسی عملکرد و ویژگیهای آن برای دو رقم سیبزمینی در روشهای آبیاری بارانی و قطرهای- نواری
Because of limiting water resources and increasing demand for food, it is necessary to investigate the effect of irrigation systems on water productivity. This research was conducted to evaluate yield and yield characteristics of two potato varieties under sprinkler and trickle irrigation systems. The treatments were two irrigation systems (sprinkler and trickle irrigation) and two potato varie...
متن کاملEffect of deficit irrigation on crop growth, yield and quality of onion in subsurface drip irrigation
Indiahas the largest area under onion (Allium cepa) crop but its average productivity (14.21 t ha-1) is considerably lower than the world’s average of 19.4 t ha-1. Besides low productivity, irrigation efficiencies are also very low i.e. 30-35% in India. Managing onion crop with less than adequate irrigation water availability is a challenge in several parts of the country. Options of i) deficit...
متن کاملModelling trickle irrigation: Comparison of analytical and numerical models for estimation of wetting front position with time
Irrigation practices that are profligate in their use of water have come under closer scrutiny by water managers and the public. Trickle irrigation has the propensity to increase water use efficiency but only if the system is designed to meet the soil and plant conditions. Recently we have provided a software tool, WetUp, to calculate the wetting patterns from trickle irrigation emitters. WetUp...
متن کاملA hierarchical partitioning method for optimizing irrigation strategies
Improving water efficiency in irrigated agriculture is a priority for better environmental and economic performance. It can be achieved by reducing the amount of water used and optimizing the timing of application. Among numerous methods, hybrid biophysical/decisional simulation models are effective tools for evaluating and comparing irrigation strategies under different weather conditions. How...
متن کاملApplication of nematicides via drip irrigation.
Use of drip, or trickle, irrigation in agriculture has increased rapidly during the past 20 years. In 1970 approximately 50,000 ha in the United States were under drip irrigation, by 1985 the area had increased to over 300,000 ha (6). Irrigation has been used to deliver fertilizers and pesticides (8,9,14,18,27,28), and there are increasing numbers of studies on the application of nematicidal co...
متن کامل