نوع مقاله : مقاله پژوهشی
نویسندگان
1 سازمان تحقیقات آموزش و ترویج کشاورزی، موسسه تحقیقات خاک و آب، بخش آبیاری و فیزیک خاک، کرج، ایران
2 سازمان تحقیقات آموزش و ترویج کشاورزی، موسسه تحقیقات فنی و مهندسی کشاورزی، بخش آبیاری و زهکشی، کرج، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
In the agricultural sector, indicators of physical productivity (WPPa), economic productivity (WPEa), physical (WPGp) and economic productivity gap (WPGe) of water are used to evaluate the performance of farmers and gardeners. The WPPa index, does not consider the price and costs of the product. The WPEa index is not only affected by inflation and market regulation policy, but also does not take into account the effect of the region's soil and climate. The WPGP and WPGe indices do not provide an accurate evaluation of water productivity of plants due to the difference in the nature of the performance of different plants. Purpose: In this study a new index is introduced that does not have any the aforementioned disadvantages.
Material and method: A relative economic water productivity index was introduced and evaluated using different data for each of the factors affecting agricultural production, including soil, plant, climate, management and inflation, and it was compared with the WPPa, WPEa, WPGP and WPGe indices. Results: The results showed that unlike other indicators, the relative economic water productivity index evaluated water productivity in different plants compared to other indicators in proportion to the production capacity of the soil and the climate of the region for any type of agricultural management without being affected by the different nature of crop plants performance and inflation (economy). Because in the KWPe index, the water productivity of each plant is estimated based on the potential conditions and these conditions are unique for each plant and in each region and climate and under each agricultural management, therefore, the productivity of different plants in different regions can be compared only with this index. So that the WPGe index estimated the average value of water productivity for wheat and barley in different soils to be equal (3973 toman/m3), but the KWPe index estimated water productivity of wheat and barley at 0.67 and 0.33, respectively. Also, the KWPp index estimated the same value for water productivity of wheat and corn as 0.42, but the KWPe index estimated 0.36 and 0.4 for wheat and corn respectively due to the high price of corn compared to wheat.
کلیدواژه‌ها [English]
Introducing and evaluation of relative economic water productivity index
EXTENDED ABSTRACT
In order to evaluate the result of any activity, a comprehensive and complete index is required to take into account all factors affecting the activity. In the field of agriculture, an index called water productivity is used for this purpose in different ways. Performance index, Benefit-Cost Ratio (B/C), Physical Water Productivity index (WPPa), Economic Water Productivity index (WPEa), Physical Productivity Gap index (WPGp) and Economic Productivity Gap index (WPGe) are used to evaluate the performance of farmers and gardeners. The WPPa index does not consider product price and costs and therefore cannot be a suitable indicator for choosing a plant for the farm or garden. The WPEa index cannot provide an accurate assessment of various crops/plants due to the influence of inflation and market regulation policy and the absence of the soil and climate properties of the regions. The water productivity gap index (WPGp & WPGe) cannot provide a correct assessment of water productivity due to the different nature of yield and price of different plants.
Therefore, it is necessary to introduce an index that firstly takes into account all factors affecting agricultural production and secondly does not get affected by factors ineffective on production, such as inflation and market regulation policies, and provides an accurate assessment of various field and garden products.
In the present study, the relative economic water productivity index (KWPe) was introduced as the ratio of economic water productivity in real conditions to economic water productivity in standard conditions (potential). This index was evaluated for different factors affecting production, including soil, plants, climate, management and inflation and compared with the traditional physical and economic water productivity and productivity gap indicators. In this research, The relative physical water productivity index (KWPp) was also calculated and compared with the KWPe. To calculate economic water productivity under potential conditions, net crop water requirement was calculated using the Penman-Monteith, and potential yield determined based on the land potential production, which depends on the soil and climate of the region.
The results showed that all factors affecting agricultural production have a logical effect on the KWPe index. But the WPPa, WPEa, KWPp, WPGe and WPGp indices are either not affected by all the factors affecting production, or they are affected by factors other than the factors affecting the reproduction of inflation and market regulations. For this reason, by using the proposed KWPe index, it is possible to assesst the crop pattern (what to plant) and the combination of cultivation (at what level to plant) with higher accuracy. Due to the fact that in the KWPe index, the water productivity of each plant is measured based on the standard conditions of each plant, the productivity of several crops in one region or a single plant in several regions can be compared using the introduced index. As the price and cost is not considered in KWPp index ca;culation, it is less accurate than the KWPe index in providing water productivity in different plants. In addition, in the KWPe, WPGe and WPGp indices, the soil and climate of the region are directly included in the water productivity index through the net water requirement and land production potential. But the soil and climate of the region are not considered in WPPa and WPEa indices. Unlike other indices, the KWPe index was not affected by the five times price of tomatoes, and introduced soybean plant as the most productive plant with a relative productivity of 0.86. Despite the equality of water productivity gap for wheat and barley (3973 toman/m3), in the same conditions, the KWPe index was estimated to be 0.67 for wheat and 0.33 for barley. In briefly in terms of accuracy, the order of proposed indicators are the WPPa, WPEa, WPGp, WPGe, KWPp and KWPe is recommended to evaluate water productivity in different plants, climates, soils, managements and inflation.
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