Your search found 18 records
1 Anwar, Arif A.; Ul Haq, Z. 2013. An old–new measure of canal water inequity. Water International, 38(5):536-551. (Special issue on "Water for food security: challenges for Pakistan" with contributions by IWMI authors). [doi: https://doi.org/10.1080/02508060.2013.832124]
Water resources ; Equity ; Irrigation management ; Irrigation systems ; Indicators ; Case studies ; Canals ; Flow discharge ; River basins ; Crops ; Seasonality / Pakistan / Punjab Province / Hakra Branch Canal
(Location: IWMI HQ Call no: PER Record No: H046131)
http://www.tandfonline.com/doi/pdf/10.1080/02508060.2013.832124
https://vlibrary.iwmi.org/pdf/H046131.pdf
https://vlibrary.iwmi.org/pdf/H046131.pdf
(0.43 MB)
The fixed-turn or warabandi system of irrigation management is aimed at providing equitable rationing of Pakistan’s limited water resources. This paper assesses the equity in practice of the warabandi system using the Gini and Theil indices. Defining equity as the delivery of an equal depth of water over the irrigated area for a crop season, distribution is relatively equitable at the distributary level. There is a need for improved indices that represent inequity and the difference between canal capacity and operational flows. This is particularly important for canals in the low- and lowest-priority subsets of the warabandi schedule.
2 Ringler, C.; Anwar, Arif A.. 2013. Water for food security: challenges for Pakistan. Water International, 38(5):505-514. (Special issue on "Water for food security: challenges for Pakistan" with contributions by IWMI authors). [doi: https://doi.org/10.1080/02508060.2013.832122]
Water resources ; Water management ; Irrigation management ; Water security ; Food security ; Food production ; Food policy ; River basins ; Institutions ; Climate change / Pakistan
(Location: IWMI HQ Call no: PER Record No: H046132)
http://www.tandfonline.com/doi/pdf/10.1080/02508060.2013.832122
https://vlibrary.iwmi.org/pdf/H046132.pdf
https://vlibrary.iwmi.org/pdf/H046132.pdf
(0.38 MB)
3 de Vries, T. T.; Anwar, Arif A.. 2015. Irrigation scheduling using complex machine scheduling. Journal of Irrigation and Drainage Engineering, 141(5):04014065-1-04014065-8. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0000824]
Irrigation systems ; Mathematical models ; Water allocation ; Water users ; Costs ; Machine learning
(Location: IWMI HQ Call no: e-copy only Record No: H046653)
(1.09 MB)
Irrigation schedules are used in many irrigation schemes that operate on a rotational or arranged-demand basis. Determining these schedules is a complex problem, especially when done by hand. Operations research tools such as single machine scheduling are already used to schedule irrigation turns in systems where only one single user can irrigate simultaneously. This paper shows how multimachine scheduling can be used to determine arranged-demand schedules for systems where two or more users can irrigate at the same time. Two models are presented, as follows: (1) the simple multimachine scheduling model that establishes a schedule for systems where all outlets/user discharges are identical, and (2) the complex multimachine scheduling model that determines the schedule when flows to individual outlet/users are not necessarily identical.
4 Anwar, Arif A.; Ahmad, W.; Bhatti, Muhammad Tousif; Ul Haq, Z. 2016. The potential of precision surface irrigation in the Indus Basin Irrigation System. Irrigation Science, 34:(5)379-396. [doi: https://doi.org/10.1007/s00271-016-0509-5]
Irrigation systems ; Surface irrigation ; Irrigation canals ; Soil texture ; Infiltration ; Discharges ; Performance indexes ; Water rates ; Farmers ; Crop production ; Evapotranspiration / South Asia / Pakistan / Khyber Pakhtunkhwa / Indus Basin Irrigation System / Maira Branch Canal
(Location: IWMI HQ Call no: e-copy only Record No: H047549)
(2.22 MB)
In this research we explore the potential of precision surface irrigation to improve irrigation performance under the warabandi system prevalent in the Indus Basin Irrigation System. Data on field dimensions, field slopes along with characteristic soil infiltration properties and outlet discharge were collected through a survey of a sample tertiary unit of Maira Branch Canal, Khyber Pakhtunkhwa Province, Pakistan. The performance of all fields in the tertiary unit was analysed and reported in aggregate, with detailed results of one field presented for illustration. The objective is to determine the optimum field layout, defined as the number of border strips, for the observed field characteristics to maximize performance. The results indicate that performance improvement is relatively easily achievable through changes in field layout within current irrigation services. Estimated application efficiency is sensitive to the selected depth of application, and it is important that a practical depth of application is selected. We recommend a depth of application of 50 mm and show how this is achievable and leads to a low quarter distribution uniformity of 0.750 and an application efficiency of 80 %. We also explore the feasibility of a 10-day warabandi rather than the 7-day warabandi and show that there is no significant change in the performance under a 10-day warabandi.
5 Anwar, Arif A.; Bhatti, Muhammad Tousif; de Vries, T. T. 2016. Canal operations planner. I: maximizing delivery performance ratio. Journal of Irrigation and Drainage Engineering, 142(12):1-12. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001091]
Irrigation systems ; Irrigation canals ; Irrigation operation ; Seasonal cropping ; Performance evaluation ; Equity ; Mathematical models ; Linear models ; Linear programming / Pakistan / Punjab / Indus Basin Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H047652)
(0.87 MB)
A key operational objective for the management of the Indus Basin Irrigation System of Pakistan is the distribution of water among tertiary canals in a transparent and equitable manner. Decisions on canal operations are disseminated as a Canal Operation Plan, or a Rotational Program, for each crop season for every canal system. The current practice for developing these plans is qualitative based on heuristics that have remain unchanged since the early development of this vast irrigation system. This paper uses operations research tools to develop a Canal Operations Planner. Allocation cost is defined as a function of the delivery performance ratio and maximizing this function. The performance of the modules is evaluated using spillage and the Gini index as a measure of equity. Two models, namely; linear programme-delivery performance ratio (LP-DPR) and non linear programme-delivery performance ratio (NLP-DPR) are presented and the results are compared to performance under current canal planning and operational practice. Both models improve the equity when compared to existing operations. The NLP-DPR model outperforms the LP-DPR both on equity and minimizing spillage.
6 Anwar, Arif A.; de Vries, T. T.; Bhatti, Muhammad Tousif. 2016. Canal operations planner. II: minimizing inequity. Journal of Irrigation and Drainage Engineering, 142(12):1-7. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001092]
Irrigation systems ; Irrigation canals ; Irrigation operation ; Water distribution ; Water supply ; Equity ; Seasonal cropping ; Performance indexes ; Farmers ; Mathematical models / Pakistan / Indus Basin Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H047653)
(0.38 MB)
Equity of water distribution is an oft-repeated and stated aim of the warabandi irrigation systems prevalent in Pakistan and parts of India. The Canal Operations Plan is one tool used to operationalize equitable distribution of water. These plans are created for every canal system every crop season. This companion paper applies operations research tools to this problem and explicitly minimizes inequity as measured by the Gini index of the cumulative depth of water supplied. The results are analyzed and compared with those obtained from the models of the companion paper that maximize delivery performance ratio (DPR) and conclude that the linear programme-delivery performance ratio (LP-DPR) model given in the companion paper is overall slightly superior to the linear programme-inequity (LP-INEQ) model presented in this paper. This paper highlights that a performance indicator of equity such as the Gini may not fully capture the sense of fairness from a farmer’s perspective. Application of this research is demonstrated through an engineering application in the preparation of a canal operations plan for the summer 2016 and winter 2016–2017 crop season.
7 Anwar, Arif A.; Haq, Z. U. 2016. Arranged-demand irrigation scheduling with nonidentical discharges. Journal of Irrigation and Drainage Engineering, 142(9):1-10. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001029]
Irrigation water ; Irrigation systems ; Irrigation canals ; Water supply ; Water demand ; Farmers ; Flow discharge ; Mathematical models ; Algorithms / Pakistan / Khyber Pukhtunkhwa Province / Maira Branch Canal
(Location: IWMI HQ Call no: e-copy only Record No: H047678)
Several irrigation water delivery methods are in practice in irrigated agriculture throughout the world, and a variety of classifications have been suggested by different researchers. Demand, arranged-demand, and rotation are the three main types of irrigation schedules/delivery methods. Irrigation systems may also be classified as either sequential or simultaneous. Supplying water sequentially to farmers according to their requested times constitutes an irrigation scheduling problem analogous to the classical earliness/tardiness single machine scheduling problems in Operational Research (OR). In this paper, the authors describe an irrigation scheduling problem analogous to the complex multimachine scheduling problem. The authors develop a genetic algorithm (GA) and test this algorithm against solutions obtained from an integer program to draw conclusions about the solution quality of the GA. The researchers demonstrate the potential of this GA through an engineering application of the Maira Branch Canal. The authors show that if this canal is operated at a constant discharge, the arranged-demand schedule requires the canal to be operated at 75% of the discharge required if this canal were operated on an on-demand schedule.
8 Ali Shah, Azeem M.; Anwar, Arif A.; Bell, A. R.; ul Haq, Zia. 2016. Equity in a tertiary canal of the Indus Basin Irrigation System (IBIS) Agricultural Water Management, 178:201-214. [doi: https://doi.org/10.1016/j.agwat.2016.09.018]
Irrigation systems ; Irrigation water ; Irrigation canals ; Water distribution ; Watercourses ; Tertiary sector ; Equity ; Discharges / Pakistan / Punjab / Hakra Canal / Indus Basin Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H047866)
This paper examines the fairness in distribution of water in a tertiary canal within the Indus Basin Irrigation System. Two methodologies are proposed: canal rating equations, and outlet discharge equations. The methodology is applied to a tertiary canal located in the Punjab, Province of Pakistan. Fairness/equity is expressed quantitatively using the Gini index. There is a difference in the estimated discharge depending on the methodology employed, however as we move along the canal the water allowance does not vary significantly with the distance along the canal. Hence for this particular canal the head-middle-tail inequity often reported and generalized in the literature is not observed. The advantage of a quantitative measure of inequity such as the Gini is exemplified by comparing the Gini with that at the secondary canal and also against itself if the tertiary canal could be operated “as designed”. We introduce two new concepts: systematic and operational inequity. Provided the costs of data acquisition can be reduced this technology has the potential to be scaled up and included in future development investments in large scale irrigation systems. Further work exploring the impact of information on stakeholders needs to be undertaken.
9 Ul Haq, Z.; Anwar, Arif A.. 2017. Simultaneous-irrigation scheduling GA [genetic algorithm] model with identical discharges and travel time. Journal of Irrigation and Drainage Engineering, 143(2):1-6. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001125]
Irrigation scheduling ; Irrigation systems ; Discharges ; Operations research ; Farmers ; Irrigation canals ; Mathematical models ; Algorithms ; Constraints
(Location: IWMI HQ Call no: e-copy only Record No: H047891)
Multimachine scheduling problems with earliness/tardiness costs and sequence-dependent setup times are analogous to the simultaneous irrigation scheduling problem with water travel times between outlets in a canal irrigation system where all the farmers are supplied with identical discharges at their requested time, i.e., arranged demand irrigation scheduling. The multimachine scheduling problem with earliness/tardiness costs even without setup consideration is computationally very demanding and optimum solutions are not possible in practical time limits. The addition of the sequence-dependent setup time and the dual goal of minimizing earliness/tardiness and the number of machines makes it even more difficult, complicated, and novel. For practical applications, meta-heuristics such as genetic algorithms, simulated annealing, or tabu search methods need to be used. This study employs the genetic algorithm (GA) model. The model presented here is an improvement over earlier work as it considers travel time in a multimachine or simultaneous irrigation system and resolves the issue of computational time by using an approximate algorithm instead of an exact algorithm. However, no quantitative comparison can be donewith earlier models as the current model accommodates travel time; hence, its objectivefunction is numerically different than earlier models. The problem is successfully modeled using GA and its implementation is demonstrated. No comprehensive data set is available that completes the requirements of rigorous testing of the GA model. Therefore, to evaluate the performance of the GA model with travel time, instances were randomly generated from a uniform distribution, for three different values of travel times. The GA model was able to obtain feasible schedules for all the instances tested.
10 Bhatti, Muhammad Tousif; Anwar, Arif A.; Aslam, Muhammad. 2017. Groundwater monitoring and management: status and options in Pakistan. Computers and Electronics in Agriculture, 135:143-153. [doi: https://doi.org/10.1016/j.compag.2016.12.016]
Groundwater management ; Groundwater development ; Water levels ; Water quality ; Water table ; Monitoring ; Food security ; Farmers organizations ; Irrigation canals ; Wells ; Tube wells ; Salinity ; Surveys ; Aquifers / Pakistan / Punjab
(Location: IWMI HQ Call no: e-copy only Record No: H048019)
Due to extensive groundwater development in the recent past, Pakistan now faces enormous challenges of groundwater management as it struggles to ensure food security for its rapidly growing population. These management challenges require a re-balancing of surface and groundwater monitoring objectives and approaches in the country. This article presents the current status of the groundwater monitoring and management in Pakistan. A compelling case is presented for optimization of material resources in improving groundwater level and quality data by proposing to use farmer organizations as a source of crowd sourced groundwater information. The authors showcase new methods to collect groundwater data and demonstrate use of automatic recording instruments for groundwater monitoring in a tertiary canal command area in the Pakistan’s Punjab. The results suggest that the potential for broader impact by engaging farmer organization and expanding monitoring networks is attractive. A common concern about long term deployment of automatic instruments is that the observation wells are not purged before extracting water quality samples. The authors address this concern through a field experiment by utilizing capabilities of automatic recording instruments.
11 de Vries, T. T.; Anwar, Arif A.; Bhatti, Muhammad Tousif. 2017. Canal operations planner. III: minimizing inequity with delivery performance ratio relaxation. Journal of Irrigation and Drainage Engineering, 143(9):1-13. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001218]
Canal construction ; Performance testing ; Performance indexes ; Irrigation systems ; Water distribution ; Equity ; Cost analysis ; Models / Pakistan
(Location: IWMI HQ Call no: e-copy only Record No: H048298)
(0.80 MB)
For many large irrigation systems, distributing water equitably is a stated management objective. Canal operations plans specify which canal to operate at what discharge for each irrigation interval to achieve the stated objective. In this study, a function of the Gini index is incorporated in to an integer program that can develop a canal operations plan. In contrast with earlier canal operations planners that minimize inequity, the operations planner presented herein does not constrain the discharge in a canal to a binary integer. Rather, the user can define an allocation cost function that in turn defines the preferred operational range of discharge over which any canal should be operated for any interval. The operations planner can also be modified to permit spillages. The model is applied to a secondary canal in Pakistan, and the sensitivity of the results to operational range and permissible spillage are explored. An engineering application of the model is presented.
12 Anwar, Arif A.; de Vries, T. T. 2017. Sequential irrigation scheduling avoiding night irrigation. Journal of Irrigation and Drainage Engineering, 143(7):1-10. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001178]
(Location: IWMI HQ Call no: e-copy only Record No: H048300)
The sequential irrigation scheduling problem is one where a set of irrigation jobs have to be scheduled sequentially. In this paper, an integer program is presented to solve this problem. The objective function is a dual-goal function that avoids night irrigation and minimizes earliness or tardiness, with the former objective taking priority over the latter. A scheduled start time cost function is introduced and is user defined to reflect the behavior and preferences (and aversions) of farmers. In this paper, the scheduled start time cost function is a piecewise linear function and uses techniques from operations research. It is linearized using the disjunctive method. The integer program is implemented in a general-purpose solver and applied to a 16-job problem to demonstrate that a schedule can be prepared that avoids night irrigation and minimizes earliness and tardiness. There is a trade-off between avoiding night irrigation and earliness and tardiness compared to earlier models that minimize only earliness and tardiness. However, the increase in earliness and tardiness for the example presented is modest.
13 Anwar, Arif A.; Bhatti, Muhammad Tousif. 2018. Pakistan’s Water Apportionment Accord of 1991: 25 years and beyond. Journal of Water Resources Planning and Management, 144(1):1-13. [doi: https://doi.org/10.1061/(ASCE)WR.1943-5452.0000831]
Legislation ; Agreements ; Treaties ; Water accounting ; Water resources ; Water allocation ; Water distribution ; Water use ; Environmental flows ; Infrastructure ; Monitoring / Pakistan / Indus River
(Location: IWMI HQ Call no: e-copy only Record No: H048816)
https://ascelibrary.org/doi/pdf/10.1061/%28ASCE%29WR.1943-5452.0000831
https://vlibrary.iwmi.org/pdf/H048816.pdf
https://vlibrary.iwmi.org/pdf/H048816.pdf
The apportionment of waters of the Indus River System between the provinces of Pakistan is widely hailed as a historic agreement. This agreement (herein referred to as the Accord) was signed into effect in 1991, just over 25 years ago. The Accord lacks a clearly stated objective and hence it is difficult to review the Accord against its objective. This paper presents a detailed thematic review of the Accord and interprets the literature and data sets that have become available over the last 25 years. Although the Accord leaves room for interpretation, which is often biased to a particular perspective, an obvious starting point that has been highlighted in the literature is to improve water accounting in the Indus basin and to clarify and document the Operating Rules. Over the next 25 years, demographic change, socioeconomic change, and climate change in the Indus Basin will place this Accord under increased scrutiny.
14 Bhatti, Muhammad Tousif; Anwar, Arif A.; Ali Shah, Muhammad Azeem. 2019. Revisiting telemetry in Pakistan’s Indus Basin Irrigation System. Water, 11(11):1-20. [doi: https://doi.org/10.3390/w11112315]
Irrigation systems ; Telemetry ; Flow discharge ; Estimation ; Sensors ; Irrigation canals ; Rivers ; Data collection ; Quality assurance ; Measuring instruments / Pakistan / Indus Basin Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H049422)
(1.82 MB) (1.82 MB)
The Indus Basin Irrigation System (IBIS) lacks a system for measuring canal inflows, storages, and outflows that is trusted by all parties, transparent, and accessible. An earlier attempt for telemetering flows in the IBIS did not deliver. There is now renewed interest in revisiting telemetry in Pakistan’s IBIS at both national and provincial scales. These investments are typically approached with an emphasis on hardware procurement contracts. This paper describes the experience from field installations of flow measurement instruments and communication technology to make the case that canal flows can be measured at high frequency and displayed remotely to the stakeholders with minimal loss of data and lag time between measurement and display. The authors advocate rolling out the telemetry system across IBIS as a data as a service (DaaS) contract rather than as a hardware procurement contract. This research addresses a key issue of how such a DaaS contract can assure data quality, which is often a concern with such contracts. The research findings inform future telemetry investment decisions in large-scale irrigation systems, particularly the IBIS.
15 Anwar, Arif A.; Ahmad, W. 2020. Precision surface irrigation with conjunctive water use. Sustainable Water Resources Management, 6(5):75. [doi: https://doi.org/10.1007/s40899-020-00434-3]
Surface irrigation ; Water use ; Conjunctive use ; Irrigation methods ; Furrow irrigation ; Border irrigation ; Groundwater irrigation ; Irrigation water ; Irrigation systems ; Canals ; Performance indexes ; Crops ; Evapotranspiration ; Cotton ; Wheat ; Precipitation ; Farmers ; Modelling / Pakistan / Indus Basin Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H049931)
(1.37 MB)
The Indus Basin Irrigation System is characterized as a gravity surface irrigation system, with minimal on-line or off-line storage and limited distribution control. An important characteristic is the limited water availability. On field irrigation within the Indus Basin Irrigation System is almost entirely using surface irrigation and only very few farms adopting pressurized irrigation systems. The objective of the warabandi management system that characterizes the Indus Basin Irrigation System is to distribute the limited available water as equitably as possible. This research evaluates surface irrigation under furrow and border strip irrigation using canal water and groundwater conjunctively. This paper presents results from a numerical model and field observations, to examine the precision surface irrigation paradigm within the water supply constraints imposed by the warabandi system of the Indus Basin Irrigation System. We conclude that laser grading within the IBIS is achievable at a modest cost and effort. Our findings suggest that the improved laser-graded profile persists for at least three crop seasons. Furrow irrigation can attain a high performance using either available canal or groundwater with low quarter distribution uniformity and low quarter application efficiency as performance indicators. Border irrigation can also attain a high performance provided irrigation is changed to fortnightly. Model predictions of advance curve and low quarter distribution uniformity are compared to field observations and in-situ measurement.
16 Bhatti, Muhammad Tousif; Ashraf, M.; Anwar, Arif A.. 2021. Soil erosion and sediment load management strategies for sustainable irrigation in arid regions. Sustainability, 13(6):3547. (Special issue: Sustainable Agricultural, Biological, and Environmental Engineering Applications) [doi: https://doi.org/10.3390/su13063547]
Soil erosion ; Sediment yield ; Irrigation systems ; Sediment transport ; Modelling ; Arid zones ; Sustainability ; Strategies ; Revised Universal Soil Loss Equation ; Rainfall-runoff relationships ; Normalized difference vegetation index ; Crop management ; Rivers ; Catchment areas ; Reservoirs ; Canals / Pakistan / Afghanistan / Gomal River
(Location: IWMI HQ Call no: e-copy only Record No: H050370)
(4.00 MB) (4.00 MB)
Soil erosion is a serious environmental issue in the Gomal River catchment shared by Pakistan and Afghanistan. The river segment between the Gomal Zam dam and a diversion barrage (~40 km) brings a huge load of sediments that negatively affects the downstream irrigation system, but the sediment sources have not been explored in detail in this sub-catchment. The analysis of flow and sediment data shows that the significant sediment yield is still contributing to the diversion barrage despite the Gomal Zam dam construction. However, the sediment share at the diversion barrage from the sub-catchment is much larger than its relative size. A spatial assessment of erosion rates in the sub-catchment with the revised universal soil loss equation (RUSLE) shows that most of the sub-catchment falls into very severe and catastrophic erosion rate categories (>100 t h-1y -1 ). The sediment entry into the irrigation system can be managed both by limiting erosion in the catchment and trapping sediments into a hydraulic structure. The authors tested a scenario by improving the crop management factor in RUSLE as a catchment management option. The results show that improving the crop management factor makes little difference in reducing the erosion rates in the sub-catchment, suggesting other RUSLE factors, and perhaps slope is a more obvious reason for high erosion rates. This research also explores the efficiency of a proposed settling reservoir as a sediment load management option for the flows diverted from the barrage. The proposed settling reservoir is simulated using a computer-based sediment transport model. The modeling results suggest that a settling reservoir can reduce sediment entry into the irrigation network by trapping 95% and 25% for sand and silt particles, respectively. The findings of the study suggest that managing the sub-catchment characterizing an arid region and having steep slopes and barren mountains is a less compelling option to reduce sediment entry into the irrigation system compared to the settling reservoir at the diversion barrage. Managing the entire catchment (including upstream of Gomal Zam dam) can be a potential solution, but it would require cooperative planning due to the transboundary nature of the Gomal river catchment. The output of this research can aid policy and decision-makers to sustainably manage sedimentation issues in the irrigation network.
17 Anwar, Arif A.; Bhatti, Muhammad Tousif. 2021. Routing field channels through a tertiary unit with heterogeneous fields. Journal of Irrigation and Drainage Engineering, 147(9):04021040. [doi: https://doi.org/10.1061/(ASCE)IR.1943-4774.0001592]
Irrigation systems ; Canals ; Open channels ; Water delivery ; Linear programming ; Models ; Water user associations ; Irrigation scheduling ; Costs ; Farmers / Pakistan / Indus Basin Irrigation System / Gomal Zam Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H050548)
(5.35 MB)
The extensive irrigation systems of South Asia are predominately a hierarchy of canals delivering water to a tertiary unit. A network of field channels transfers water within the tertiary unit to the field where it is applied using surface irrigation. The network of field channels within a tertiary unit is often left to the farmers/farmer associations to construct, maintain, and operate. This paper develops a mathematical model/algorithm for routing the field channel along the existing field boundaries such that every field is serviced by a field channel and minimizing the total length of the field channel as a proxy measure of the cost of construction of field channels. The models developed in this paper are formulated as integer programs, implemented in a general-purpose solver. The model is applied to a tertiary unit of the Gomal Zam Irrigation System in Pakistan and shows that for this particular application, the optimized total length of field channels is 9,463 m compared with 11,313 m when an expert judgment is used, a reduction of 1,850 m (20%).
18 Bhatti, Muhammad Tousif; Anwar, Arif A.. 2022. Statistical verification of 16-day rainfall forecast for a farmers advisory service in Pakistan. Agricultural and Forest Meteorology, 317:108888. [doi: https://doi.org/10.1016/j.agrformet.2022.108888]
Farmers ; Advisory services ; Rain ; Weather forecasting ; Precipitation ; Information dissemination ; Decision making ; Weather data ; Models / Pakistan / Khyber Pakhtunkhwa
(Location: IWMI HQ Call no: e-copy only Record No: H051020)
https://www.sciencedirect.com/science/article/pii/S0168192322000818/pdfft?md5=cdd1f03708ec8f965a5701e5d9c51971&pid=1-s2.0-S0168192322000818-main.pdf
https://vlibrary.iwmi.org/pdf/H051020.pdf
https://vlibrary.iwmi.org/pdf/H051020.pdf
(6.48 MB) (6.48 MB)
Rainfall forecast is useful for farmers to avoid expensive irrigation decisions both in rain-fed and irrigated agricultural areas. In developing countries, farmers have limited knowledge of weather forecast information sources and access to technology such as the internet and smartphones to make use of these forecasts. This paper presents a case of developing Farmers Advisory Service (FAS) in Pakistan that is based on rainfall forecast data. The analysis emphasizes on statistical verification of 16-day rainfall forecast data from a global weather forecast model (Global Forecast System). In-situ data from 15 observatories maintained by Pakistan Meteorological Department in Khyber Pakhtunkhwa province has been considered for verification. Scores of various indicators are calculated for the rainfall forecast ranging from simple forecasts of dichotomous outcomes to forecasts of a continuous variable. A sensitivity analysis is also performed to understand how scores of dichotomous indicators vary by changing the threshold to define a rainfall event and forecast lead time interval. The quality of forecast varies across the stations based on the selected skill scores. The findings of verification, sensitivity analysis, and attributes of FAS provide insight into the process of developing a decision support service for the farmers based on the global weather forecast data.
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