Papers by Qaisar Saddique
Water, 2021
Drought is a natural phenomenon caused by the variability of climate. This study was conducted in... more Drought is a natural phenomenon caused by the variability of climate. This study was conducted in the Songhua River Basin of China. The drought events were estimated by using the Reconnaissance Drought Index (RDI) and Standardized Precipitation Index (SPI) which are based on precipitation (P) and potential evapotranspiration (PET) data. Furthermore, drought characteristics were identified for the assessment of drought trends in the study area. Short term (3 months) and long term (12 months) projected meteorological droughts were identified by using these drought indices. Future climate precipitation and temperature time series data (2021–2099) of various Representative Concentration Pathways (RCPs) were estimated by using outputs of the Global Circulation Model downscaled with a statistical methodology. The results showed that RCP 4.5 have a greater number of moderate drought events as compared to RCP 2.6 and RCP 8.5. Moreover, it was also noted that RCP 8.5 (40 events) and RCP 4.5 ...
Environmental Science and Pollution Research, 2021
Rapid population growth integrated with poor governance and urban planning is highly challenging ... more Rapid population growth integrated with poor governance and urban planning is highly challenging resulting key for the selection of unsuitable landfill sites, particularly in developing counties. Therefore, the aim of this study is to investigate the suitable solid waste landfill sites in the capital of the country as a case study, by the integration of Geographical Information System (GIS) with fuzzy logic, analytical hierarchy process (AHP), and weighted linear combination (WLC) method based on multi-criteria decision-making (MCDM). We chose thirteen (13) criteria (9 factors and 4 constraints) and grouped them into two main categories (environmental and socioeconomic) to achieve the objectives. The AHP was employed to evaluate the relative importance of the factors followed by standardization of criteria factors based on fuzzy set theory. Subsequently, all criteria factors were combined based on AHP and fuzzy logic-WLC method in order to obtain land suitability map. Finally, the sites were identified by the intersection of two combined suitability index layers. The obtained results depicted that the integration of fuzzy logic, AHP, and WLC technique with GIS can produce satisfactory results for the suitable locations of solid waste landfill sites over complex topographic regions. Overall, the land suitability obtained based on fuzzy-WLC is more refined and smooth because of its better segregation and its potential to consider full tradeoff between factors and average risk. The AHP was identified (47 km2) as high suitable while fuzzy-WLC generated 36 km2 as suitable area. Finally, the intersection of both suitability index map shows numerous suitable landfill sites available in Islamabad city; however, the surface areas of the sites are small at individual level (less than 15 ha).
Environmental Science and Pollution Research, 2020
Solar radiation (SR) is essential for yield improvement in lentil, which is a crop of marginal en... more Solar radiation (SR) is essential for yield improvement in lentil, which is a crop of marginal environments. Herein, experiments were conducted over 2 years under a semi-arid environment to study the radiation interception (RI), efficiency, growth, and development of three lentil genotypes (
Field Crops Research, 2021
Abstract Plastic film mulching (PM) has a compensatory effect on crop growing degree days by incr... more Abstract Plastic film mulching (PM) has a compensatory effect on crop growing degree days by increasing soil temperature. However, only few studies addressed the question whether a terminal time for the compensatory effect window exists and if it exists how it can be quantified. The objective of this study was to use the logistic equation to describe the cumulative crop plant height and to quantify the compensatory effect. Crop apical meristem emergence was used as the reference for the terminal time of the compensatory effect window. A three-year field experiment (2013–2016), conducted under continuous PM in a typical winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) rotation on the Loess Plateau, Northwest China, indicated that the logistic equation performed well in representing and quantifying the compensatory effect of PM. The compensatory effect of PM reached a plateau during winter wheat growing seasons due to the lack of increased soil temperature during regreening stage, and during summer maize growing seasons due to unfavorably delayed senescence. The terminal time can be estimated during winter wheat and summer maize growing seasons from thermal time nodes at the maximum slope (t2) and second inflection point (t3), respectively. The compensatory coefficients could be estimated by thermal time intervals of (0, t1) and (t1, t2)in winter wheat growing seasons and thermal time internals (0, t1), (t1, t2), and (t2, t3) in summer maize growing seasons, respectively. Compensatory coefficients tended to increase with maize plant development. The minimum data requirement using a logistic equation to calculate compensatory coefficients includes data for staged plant height and mean daily air temperature.
Mitigation and Adaptation Strategies for Global Change, 2020
Agricultural adaptation is crucial for sustainable farming amid global climate change. By harness... more Agricultural adaptation is crucial for sustainable farming amid global climate change. By harnessing projected climate data and using crop modeling techniques, the future trends of food production can be predicted and better adaptation strategies can be assessed. The main objective of this study is to analyze the maize yield response to future climate projections in the Guanzhong Plain, China, by employing multiple crop models and determining the effects of irrigation and planting date adaptations. Five crop models (APSIM, AquaCrop, DSSAT, EPIC, and STICS) were used to simulate maize (Zea mays L.) yield under projected climate conditions during the 2030s, 2050s, and 2070s, based on the combination of 17 General Circulation Models (GCMs) and two Representative Concentration Pathways (RCPs 6.0 and 8.5). Simulated scenarios included elevated and constant CO 2 levels under current adaptation (no change from current irrigation amount, planting date, and fertilizer rate), irrigation adaptation, planting date adaptation, and irrigation-planting date adaptations. Results from both maize-producing districts showed that current adaptation practices led to a decrease in the average yield of 19%, 27%, and 33% (relative to baseline yield) during the 2030s, 2050s, and 2070s, respectively. The future yield was projected to increase by 1.1-23.2%, 1.0-22.3%, and 2-31% under irrigation, delayed planting date, and double adaptation strategies, respectively. Adaptation strategies were found effective for increasing the future average yield. We conclude that maize yield in the Guanzhong Plain can be improved under future climate change conditions if irrigation and planting adaptation strategies are used in conjunction.
European Journal of Agronomy, 2020
Climate change in China would cause change into precipitation patterns and rise in temperature. T... more Climate change in China would cause change into precipitation patterns and rise in temperature. The assessment of climate change impact on Chinese wheat production is needed for both rainfed and irrigated farming in order to maintain wheat self-sufficiency and to assure future food demand. The current study assesses the future trends of wheat yield in Guanzhong Plain, China by employing the calibrated Agricultural Production Systems sIMulator (APSIM)-wheat model and using the downscaled daily climate projections for 32 general circulation models (GCMs), under two representative concentration pathways (RCP 4.5 and RCP 8.5). Simulations were carried out for rainfed cropping and various levels of irrigation for future time windows of 2030s, 2060s, and 2090s. The climate projections show an overall gradual increase in future temperature and precipitation for the region. It was found that the climate change would shorten the growing period of winter wheat, as the flowering shifted back on an average by 8-18 days and 10-34 days, under RCP4.5 and RCP8.5, respectively. Similarly, maturity date shifted back on an average by 8-16 days and 10-32 days under RCP4.5 and RCP8.5, respectively. An improvement in the future rainfed winter wheat yield was noted for all simulation time periods, and the average yield increase was 6.75 %, 21.5 % and 26.5 % for 2030s, 2060s, and 2090s, respectively. Irrigation provided at a threshold of 10 % and 20 % of plant available water capacity (PAWC) was found suitable to be used as supplementary irrigation, and it resulted an overall improvement of 27 % in rainfed yield. Any increase in yield for irrigation provision beyond 20 % PAWC threshold was not statistically significant. It was found that the optimum irrigation amount with high water use efficiency (WUE) would range from 90 mm to 132 mm and up to 56 % of water can be saved by avoiding irrigation with thresholds over 20 % PAWC. These results could help policy makers and farmers to adapt accordingly in future, ensuring the sustainable and improved wheat production in this region. 1. Introduction Categorical changes in global climatic conditions and their impact on agriculture has become a widely discussed issue around the world. These variations in climate are generally associated with the global warming, which is caused by the axiomatic increase in greenhouse gas emissions. The impacts of climate change could be both detrimental and beneficial for agriculture, mainly depending on the region and cultivar type (Abraham and Dollison, 2019). Wheat, which is grown at the largest scale all over the world (FAO, 2014), will be largely affected with the change in the future climate. For example, one degree (°C) increase in global temperature might lead to 6% yield decline in most of the wheat growing parts of the world (Asseng et al., 2015; Liu et al., 2016). However, in some parts of the world wheat might also benefit from the warming climate. For instance, Sommer et al. (2013) estimated 12 % increase in the wheat yields in central Asian regions,
Atmosphere, 2020
The ongoing global warming and changing patterns of precipitation have significant implications f... more The ongoing global warming and changing patterns of precipitation have significant implications for crop yields. Process-based models are the most commonly used method to assess the impacts of projected climate changes on crop yields. In this study, the crop-environment resource synthesis (CERES)-Maize 4.6.7 model was used to project the maize crop yield in the Shaanxi Province of China over future periods. In this context, the downscaled ensemble projections of 17 general circulation models (GCMs) under four representative concentration pathways (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5) were used as input for the calibrated CERES-Maize model. Results showed a negative correlation between temperature and maize yield in the study area. It is expected that each 1.0 °C rise in seasonal temperature will cause up to a 9% decrease in the yield. However, the influence of CO2 fertilization showed a positive response, as witnessed by the increase in the crop yield. With CO2 fertilization, the...
Agricultural Water Management, 2021
Uncertainty in the availability of water supply pose challenges to traditional irrigation approac... more Uncertainty in the availability of water supply pose challenges to traditional irrigation approaches. Regulating the amount and time of irrigation at different crop growth stages could provide a solution to optimize the irrigation water amid drought periods. This study evaluated the effect of different deficit irrigation levels on maize (Zea mays L.) at several growth phases over two growing seasons (2012 and 2013) in Yangling, Shaanxi province of China. Total nine irrigation treatments incorporated three irrigation amount ratios, i.e., control irrigation (CK, 100 % of crop evapotranspiration), and 80 % and 60 % of control irrigation; named as T2-T9. Among the irrigation treatments, grain yield ranged from 6392 to 9362 kg ha-1 and seasonal water use efficiency (WUE) varied from 20.3 to 34.9 kg ha-1 mm-1 , whereas the irrigation water use efficiency (IWUE) ranged between 32.0 and 58.1 kg ha-1 mm-1. T2 that received 80 % irrigation between V8 and R6 growth stage had overall higher yield than CK, and this was closely followed by T4 that received 80 % irrigation at growth phase V3-V8 and V11-Tasseling, full irrigation at V8-V11, and 60 % irrigation between Tasseling and Maturity. Due to near optimum growing season temperature in 2013, larger WUE was noted in comparison to 2012, that resulted 16 % larger yield with 10 % lesser ETc, on an average, whereas 2012 growing season had better IWUE because of 37.5 % smaller irrigation consumption. Maize grain yield in response to water stress (Ky, the yield response factor) was 0.66, suggesting that the environmental conditions of the study area favor the application of deficit irrigation. The maize yield response to reduced irrigation supply in this experiment indicated that regulated deficit irrigation might help growers to cope with decline in water availability during growing season.
Agricultural Water Management, 2021
The physiological response of winter wheat under short-term drought conditions and the sensitivit... more The physiological response of winter wheat under short-term drought conditions and the sensitivity of different indices to soil water changes
Soil and Tillage Research, 2020
The effects of irrigation model and Nitrogen (N) fertilization on rice evapotranspiration and yie... more The effects of irrigation model and Nitrogen (N) fertilization on rice evapotranspiration and yield were studied in an experiment of pool culture with in rainproof shelter. Results showed that irrigation model and nitrogen fertilization had significantly influence on rice growth and photosynthetic capacity and yield and quality. Compared with the conventional irrigation, the plant height, rice water consumption, water requirement intensity and valid panicle number decreased and while water use efficiency, grain number perspike and seed setting rate in creased under control irrigation. With the in cement of N application rates, rice water consumption, water requirement intensity, effect panicle number and grain number per spikein creased, while setting-seed rate and 1000-grain weight decreased. Use the controllable irrigation technology, which had obvious effects of yield and quality on rice with the raise of N fertilizer rate. The yield reached 11489 kg/hm 2 and 10126 kg/hm 2 when the treatments was with 180 kg/Nhm 2 and 270 kg/Nhm 2 , which was significantly higher than the treatment of CIN1and C2N1. The determination results showed that the palatability value of C1N2 was highest to 79.3, the cooking quality was improved. Then analyzed water and nitrogen fertilizer, yield and water use efficiency were highest at 180 kg/hm 2 of N applied. We concluded that control irrigation model combined with suitable N application rate (180 kg/hm 2) could benefit for rice production by reducing cost and gaining high yield.
Agricultural Water Management, 2019
Irrigation and nitrogen (N) fertilization play important roles in grain yield. However, amounts s... more Irrigation and nitrogen (N) fertilization play important roles in grain yield. However, amounts supplied in excess of crop demand are responsible for water and N leaching during intensive agricultural production. A three-year winter wheat (Triticum aestivum L.)-summer maize (Zea mays L.) rotation experiment involving varied irrigation and N fertilization treatments was conducted in the Jinghui Canal irrigation area of Guanzhong Plain in China. To develop a more sustainable agroecosystem taking into account crop yields, deep percolation and N leaching, the RZWQM2 model was used to simulate crop production. Various irrigation and N fertilization strategies were simulated to obtain high crop yields and to reduce water and N leaching in different precipitation years, using long-term historical weather data spanning 57 years (1961-2017). The simulated soil water and NO 3-N content, grain yield, water and nitrogen use efficiencies (with nRMSE values ranging from 5.3-25.1 %), and the simulated crop biomass and N uptake (with RE values ranging from-16.4-18.3 %) were in good agreement with observed data. Simulated LAI values were acceptable (with RMSE ranging from 0.31 to 1.68 and index of agreement, d, ranging from 0.28 to 0.94), with the poorer simulations occurring with water and N stress. Maize seedling stage and wheat jointing stage were the phases most sensitive to water deficit, and optimal irrigation schedules could be adjusted according to variable precipitation and other climate changes. The best irrigation strategies for maize in the Guanzhong Plain were irrigation applied at the seedling stage in wet and normal years, and two irrigations applied at the seedling and jointing stages in dry years. The best irrigation strategies for wheat were two, three, and four irrigations applied in wet, normal, and dry years, respectively. Irrigation at different crop growth stages significantly influenced N leaching and nitrogen use efficiency. Increasing N input led to greater water use efficiency and less deep percolation water. Considering the interactive effects of water and N input on yield, deep percolation, and N leaching, the most appropriate N application rates in all precipitation years were 140 kg N ha-1 for maize and 240 kg N ha-1 for wheat, coupled with the recommended irrigation strategies. Improving water and N management can significantly reduce deep percolation of water and N leaching while maintaining agricultural productivity and environmental sustainability. 1. Introduction Water is vital essential element for crop development and yield. Water scarcity has become a global systemic risk (Sun et al., 2016). The total water resources of China are 2876 billion m 3 , accounting for 6 % of global water resources. Agricultural water accounts for 62.3 % of China's total water consumption, and shows a decreasing trend (Ministry of Water Resources of the People's Republic of China, 2016). Agricultural irrigation is the largest water consumer in China. The insufficient water resource challenges the sustainability of conventional agricultural practices and is a major factor limiting agricultural production in China (Dadrasan et al., 2015; Kang et al., 2017). This situation stresses the urgent need to identify reasonable irrigation management recommendations to improve crop water use efficiency (WUE) and achieve reductions in deep percolation below the crop root zone, while maintaining high grain yields. Meanwhile, the influence of
Agronomy, 2019
Summer maize (Zea mays L.) is a widely cultivated crop in the arid and semi-arid Guanzhong region... more Summer maize (Zea mays L.) is a widely cultivated crop in the arid and semi-arid Guanzhong region of China. However, due to the spatial and temporal variation in rainfall, the seasonal maize yield varies substantially and occasionally is not economical for poor farmers to produce. Recent water-saving agricultural practices were developed by the government to make it possible to apply supplementary irrigation at optimum sowing dates to maximize maize production under limited rainfall in the region. CERES (Crop Estimation through Resource and Environment Synthesis)-maize model was used to identify the appropriate irrigation strategies, crop growth stages and sowing dates for sustainable maize production. Model calibration process were carried out for full irrigation treatments of four growing seasons, (2012–2015). The data used for calibration included: Crop phenology, grain yield, aboveground biomass and leaf area index. The calibration phase model showed good agreement between simul...
2019 Boston, Massachusetts July 7- July 10, 2019, 2019
Remote Sensing, 2019
Accurate information of crop growth conditions and water status can improve irrigation management... more Accurate information of crop growth conditions and water status can improve irrigation management. The objective of this study was to evaluate the performance of SAFYE (simple algorithm for yield and evapotranspiration estimation) crop model for simulating winter wheat growth and estimating water demand by assimilating leaf are index (LAI) derived from canopy reflectance measurements. A refined water stress function was used to account for high crop water stress. An experiment with nine irrigation scenarios corresponding to different levels of water supply was conducted over two consecutive winter wheat growing seasons (2013–2014 and 2014–2015). The calibration of four model parameters was based on the global optimization algorithms SCE-UA. Results showed that the estimated and retrieved LAI were in good agreement in most cases, with a minimum and maximum RMSE of 0.173 and 0.736, respectively. Good performance for accumulated biomass estimation was achieved under a moderate water st...
Atmospheric Research, 2018
This paper investigates the annual and seasonal precipitation variability at 20 stations over upp... more This paper investigates the annual and seasonal precipitation variability at 20 stations over upper Indus River basin (UIRB) by using an innovative trend analysis (ITA) method, Mann-Kendall (MK) and Sen's slope estimator tests. Moreover, the annual precipitation time series is investigated for five precipitation intensities i.e. light, low, moderate, high and heavy; and on a seasonal scale for extreme values i.e. light and heavy precipitation intensities. Annual precipitation showed an increasing trend at four stations in the northeast region and a decreasing trend at two stations in the southeast region of UIRB. On a seasonal scale, the results showed that Garidopatta, Peshawar, Astore and Gupis stations are more sensitive to seasonal precipitation variabilities. Changes in heavy precipitation (> 90 th percentile) are found more severe in winter and summer seasons in the northern regions suggesting a probable flooding aggravation. However, a reduction in flooding event observed during the spring season in the southern regions of the UIRB indicating a shift in the precipitation regime from south to north. The results of light precipitation (< 10 th percentile) intensity showed that winter and spring seasons are more vulnerable to the occurrence of prolonged drought events. Moreover, ITA method has the advantage of detecting the sub-trends in the precipitation series because of its ability to present the results in graphical format. The results of this study could help to understand seasonal and annual precipitation variability over UIRB and will have imperative insinuations for further studies.
Agricultural Water Management, 2019
Soil infiltration and Manning's roughness values are key parameters to determine the performance ... more Soil infiltration and Manning's roughness values are key parameters to determine the performance of surface irrigation. However, temporal variability in these parameters due to tillage practices, irrigation, and crop growth greatly hinders efforts to improve irrigation quality. The objective of this experiment was to evaluate effects of infiltration and surface roughness variation on irrigation water movement and irrigation performance indicators for border irrigation with three border lengths. Field experiments were conducted from 2013 to 2015 in a wheat (Triticum aestivum)-maize (Zea mays L.) rotation planting system at the Jinghui Canal Irrigation Area in Guanzhong Plain of northwest China. In this work, Manning's equation and a surface irrigation simulation model (WinSRFR) were used to estimate Manning's roughness values and Kostiakov soil infiltration parameters. We determined that both parameters reached moderate levels of variation for both deep and shallow tillage treatments. The impacts of temporal variation in soil infiltration and surface roughness on irrigation water movement and irrigation quality were then evaluated. Results showed that water advance times varied significantly while recession times varied much more, affecting irrigation water amounts at various distances along the length of the border. Irrigation performance indicators were significantly different over various irrigation seasons, especially for borders that were 235 m in length. Finally, considering these temporal variations during the two rotation cycles, combinations of inflow rate and cutoff ratio during different irrigation seasons were optimized, and high irrigation quality could be achieved for 80 m and 120 m borders, but not for 235 m borders. Water percolation amounts during the 2013-2014 and 2014-2015 growing periods were reduced by 55 mm and 107 mm for 235 m borders, 26 mm and 23 mm for 120 m borders, and 36 mm and 39 mm for 80 m borders, respectively. Therefore, utilizing optimal combinations of inflow rate and cutoff ratio and considering temporal variation in soil infiltration and Manning's roughness could maintain high water application efficiency and sustainable utilization of limited water resources. as low water application efficiency and low uniformity (Gillies and Smith, 2005). The main grain crops planted in the Jinhui Canal Irrigation Area are wheat and maize (Liu and Zhu, 2011; Zhang et al., 2016). However, because of differences in crops grown, weather conditions, and tillage practices, irrigation performance varies significantly across the region, creating major problems in determining best management practices that will result in high water use efficiency in irrigated areas. Soil water infiltration is one of the most important processes affecting the volume, transport route, and water quality of agricultural drainage (Berehe et al., 2013), and is a key parameter in surface
Journal of Integrative Agriculture, 2018
Aerated irrigation has been proven to increase crop production and quality, but studies on its en... more Aerated irrigation has been proven to increase crop production and quality, but studies on its environmental impacts are sparse. The effects of aeration and irrigation regimes on soil CO 2 and N 2 O emissions in two consecutive greenhouse tomato rotation cycles in Northwest China were studied via the static closed chamber and gas chromatography technique. Four treatments, aerated deficit irrigation (AI1), non-aerated deficit irrigation (CK1), aerated full irrigation (AI2) and non-aerated full irrigation (CK2), were performed. The results showed that the tomato yield under aeration of each irrigation regime increased by 18.8% on average compared to non-aeration, and the difference was significant under full irrigation (P<0.05). Full irrigation significantly increased the tomato yield by 23.9% on average in comparison to deficit irrigation. Moreover, aeration increased the cumulative CO 2 emissions compared to non-aeration, and treatment effects were significant in the autumn-winter season (P<0.05). A slight increase of CO 2 emissions in the two seasons was observed under full irrigation (P>0.05). There was no significant difference between aeration and non-aeration in soil N 2 O emissions in the spring-summer season, whereas aeration enhanced N 2 O emissions significantly in the autumn-winter season. Furthermore, full irrigation over the two seasons greatly increased soil N 2 O emissions compared to the deficit irrigation treatment (P<0.05). Correlation analysis indicated that soil temperature was the primary factor influencing CO 2 fluxes. Soil temperature, soil moisture and NO 3 were the primary factors influencing N 2 O fluxes. Irrigation coupled with particular soil aeration practices may allow for a balance between crop production yield and greenhouse gas mitigation in greenhouse vegetable fields.
Water Resources Management, 2017
Effective drought prediction methods are essential for the mitigation of adverse effects of sever... more Effective drought prediction methods are essential for the mitigation of adverse effects of severe drought events. This study utilizes the Reconnaissance Drought Index, Standardized Precipitation Index and Standardized Precipitation Evapotranspiration Index to assess the occurrence of future drought events in the study area of the Heilongjiang province of Water Resour Manage
Water Resources Management, 2016
Precise analysis of spatiotemporal trends of temperature, precipitation and meteorological drough... more Precise analysis of spatiotemporal trends of temperature, precipitation and meteorological droughts plays a key role in the sustainable management of water resources in the given region. This study first aims to detect the long-term climate (monthly/seasonally and annually) trends from the historical temperature and precipitation data series by applying Spearmen's Rho and Mann-Kendall test at 5 % significant level. The measurements of both Water Resour Manage
Chemosphere, 2013
h i g h l i g h t s We measured 29 N 2 and 30 N 2 using membrane inlet mass spectrometry. Potenti... more h i g h l i g h t s We measured 29 N 2 and 30 N 2 using membrane inlet mass spectrometry. Potential anammox rates varied spatially and temporally in the studied rivers. Water temperature and NO À 3 in sediments were the main controls of anammox activity. Candidatus Kuenenia was the dominated anammox species in the river sediments.
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Papers by Qaisar Saddique