1. Introduction
Prolonged drought, dry conditions, and poor irrigation and water supply management result in a significant reduction in water reserves and resources [
1]). Irrigation water reductions are based on studies of percentage reductions in the required volume of irrigation water and crop responses to these reductions. The required irrigation volume for each crop is calculated based on the evapotranspiration (ET) of each crop, which has been empirically found (Epan) in the past [
2]. However, the need for an accurate measurement of ET today remains imperative and is an integral element in the decision-making of Water Policy Bodies. The continuous decrease in rainfall in Cyprus [
3,
4] (Cyprus Meteorological Services, 2020/2021) in recent decades has contributed to an increase in irrigation and, therefore, the volumes of water consumed in agriculture. However, the reckless use of irrigation water combined with reduced rainfall caused a serious blow to the storage of water in Cyprus [
5].
2. Methods
ETc forecasts based on remote sensing are almost universally used due to the following advantages of remote sensing: abundant raw data, low cost, and weather forecasting. It is worth noting that Landsat 7 ETM+ and 8 OLI images cover almost the entire island of Cyprus, and their resolution is good for hydrological studies. The study area is in the village of Mandria in the Paphos Region (west of Cyprus), which is the main agricultural area of the Paphos Region and absorbs the largest amount of water (26%) in the water supply system of Cyprus. Remote sensing techniques have been applied to estimate the accurate irrigation volumes per crop and finally compared to the empirical values that farmers are already using.
3. Results and Discussions
To produce these results, evapotranspiration maps were created where users can see the needs of their crops on a daily or even monthly basis (
Figure 1). These maps are essentially the satellite images of the area, which were converted into maps using the SEBAL algorithm [
6] after its application in the ERDAS Imagine software (version 16).
Table 1 shows the results of the project for the crops under investigation. The aim was to create an irrigation plan from which the producer would know the required irrigation volumes. It is noted that the results of this project, in terms of evapotranspiration, are given in mm/day, which, however, are easily converted to m
3/ha/month for comparison purposes with previous research data referred to in the “Norm Input Output Data for the main crop and livestock enterprises of Cyprus” [
7], which are listed in that format. The specific manual (Norm) published by the Agricultural Research Institute is the only technical and economic database in Cyprus for issues related to agricultural crops.
The research data of this project were converted into irrigation costs after multiplying with the cost of irrigation water, which amounts to EUR 0.17/ton (
Table 2). So, the project data are now comparable to the data mentioned in the Norm. This study focuses on the cost of irrigation, which appears to be a major expense for producers today. More specifically, the cost of irrigation for the crops amounts to 19%, 25%, 23%, and 5% of the variable costs, respectively, and to 12%, 19%, 17%, and 4% of the total costs, respectively. It is, therefore, indisputable that the cost of irrigation contributes to a reduction in the profit of the producer since it can contribute 20% to the formation of the cost of cultivation. A reduction in the cost of irrigation has positive inductive effects on the producer’s profit, which is the final demand for producer–entrepreneurs.
4. Conclusions
It is clear from the new data produced by this research project that the producer’s profit increases. In addition to the benefit of the producer, however, at the microeconomic level, there are also social benefits. The use of satellite remote sensing in the field of irrigation and water resources management can contribute at a microeconomic level to the maximization of the producer’s profit. The reduction in irrigation costs, using the optimal amounts of water for the needs of the crops, contributes dynamically to the profit margin of the producer while, at the same time, having a positive effect on the storage of surface water resources stored in the dams. All these positive research results fade out unless there is a proper advisory service that disseminates this knowledge. Although the Ministry of Agriculture, Rural Development and Environment in Cyprus has undertaken a great effort to establish an efficient system for agricultural knowledge and innovation (AKIS) to promote innovation in the agri-food sector, it should be improved by becoming even more integrated and powerful providing farmers better access to education and training programs.
Author Contributions
Conceptualization, G.P.; methodology, G.P.; software, G.K.; validation, G.P., D.H. and M.T.; formal analysis, G.P.; investigation, G.K.; resources, D.H.; data curation, G.P.; writing—original draft preparation, M.T.; writing—review and editing, G.P.; visualization, G.K.; supervision, G.P.; project administration, G.P. All authors have read and agreed to the published version of the manuscript.
Funding
This project was funded by the European Union. The views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or Research Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
The data are contained within the article.
Acknowledgments
The authors would like to express their appreciation to the European Union under the CARBONICA project (HORIZON-WIDERA-2022).
Conflicts of Interest
The authors declare no conflict of interest.
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