Vulnerability and adaptability of wheat production in different climatic zones of Pakistan under climate change scenarios

Ten wheat production sites of Pakistan were categorized into four climatic zones i.e. arid, semi-arid, sub-humid and humid to explore the vulnerability of wheat production in these zones to climate change using CSM-Cropsim-CERES-Wheat model. The analysis was based on multi-year (1971–2000) crop model simulation runs using daily weather series under scenarios of increased temperature and atmospheric carbon dioxide concentration (CO₂) along with two scenarios of water management. Apart from this, sowing date as an adaptation option to offset the likely impacts of climate change was also considered. Increase in temperature resulted in yield declines in arid, semi-arid and sub-humid zone. But the humid zone followed a positive trend of gain in yield with rise in temperature up to 4°C. Within a water regime, increase in CO₂ concentration from 375 to 550 and 700 ppm will exert positive effect on gain in wheat yield but this positive effect is significantly variable in different climatic zones under rainfed conditions than the full irrigation. The highest response was shown by arid zone followed by semi-arid, sub-humid and humid zones. But if the current baseline water regimes (i.e. full irrigation in arid and semi-arid zones and rainfed in sub-humid and humid zones) persist in future, the sub-humid zone will be most benefited in terms of significantly higher percent gain in yield by increasing CO₂ level, mainly because of its rainfed water regime. Within a CO₂ level the changes in water supply from rainfed to full irrigation shows an intense degree of responsiveness in terms of yield gain at 375 ppm CO₂ level compared to 550 and 700 ppm. Arid and semi-arid zones were more responsive compared to sub-humid and humid zones. Rise in temperature reduced the length of crop life cycle in all areas, though at an accelerated rate in the humid zone. These results revealed that the climatic zones have shown a variable intensity of vulnerability to different scenarios of climate change and water management due to their inherent specific and spatial climatic features. In order to cope with the negative effects of climate change, alteration in sowing date towards cooler months will be an appropriate response by the farmers.     

Earthquake triggered soft sediment deformational structures (seismites) in the Karewa formations of Kashmir valley–An indicator for palaeo-seismicity

The intermontane Karewa basin contains a wide variety of seismically induced soft sediment deformation structures, interpreted as seismites and occurs in 1300 m thick succession of upper and lower Karewas. The Karewa Formation of Kashmir valley are glacio- fluvial-lacustrine and aeolian loess of Plio-Pleistocene age. The soft sediment deformational structures occurs in various formations and members of Karewas and vary greatly in terms of morphology and pattern. The Karewa Formations were frequently confronted with recurrent seismic activities during differential upliftment of Pir Panjal and Zanaskar ranges which resulted in various deformation structures during their evolution and development. In the present study, an attempt has been made to relate the palaeo-seismicity events in Karewa formations with the deformed structures of various formations. The origin of these deformational structures have been interpreted and analyzed from the field evidences by applying paleo-seismological approach. During and after the deposition of Karewas different soft sediment deformation structures (seismites) like load cast, convolute lamination, pseudonodules, recumbent folds, sand dykes etc. were formed during liquefaction and triggered by tectonic impulsive events. The deformational structures are evidenced by their unique nature, distribution, association, behaviour and deformation, and can be used as vital indicators for palaeo-seismicity.     

A study of the roughness effects of multiple windbreaks

A wind-tunnel study of the roughness effect of a network of uniformly spaced long parallel windbreaks has been attempted. The roughness parameterZ ₀ in the well-known logarithmic profile has been obtained as a function of the ratio of the spacingL to heightH of the barriers. In one part of the study, a naturally developing boundary layer was used and the windbreaks were not spread on the entire wind-tunnel floor. Spacing ratiosL/H of 1 to 20 were treated. In the other part of the study, spires were used to thicken the boundary layers artificially and the windbreaks were spread throughout the wind-tunnel floor. In this case, spacing ratiosL/H of 1 to 30 were examined.Values of the roughness parameter obtained from the above two cases have been compared to some (though very few) previously published pertinent values.     

Identification of the Phytoremediation Potential of Indian mustard Genotypes for Copper,Evaluated from a Hydroponic Experiment

The effectiveness of 10 Indian mustard (Brassica juncea L.) genotypes (viz. Agrani, BTO, Kranti, Pusa Bahar, Pusa Basant, Pusa Bold, Pusa Jai Kisan, Vaibhav, Vardhan, and Varuna) were evaluated for their potential to phytoremediate copper from contaminated waters under laboratory controlled conditions. The genotypes were grown for 20 days in aqueous solutions containing various concentrations of copper sulfate (0–50 µM) in a hydroponic chamber. Throughout plant development, changes in growth variables, biomass accumulation, and total Cu content were evaluated. The results suggested that Indian mustard cv. Pusa Jai Kisan possesses the best capacities of Cu sequestration and tolerance amongst all the genotypes studied. Thus, Pusa Jai Kisan has the greatest potential to become a viable candidate in the development of practical phytoremediation technologies for Cu contaminated sites.     

Adaptive state estimation of groundwater contaminant boundary input flux in a 2-dimensional aquifer

In many circumstances involving heat and mass transfer issues,it is considered impractical to measure the input flux and the resulting state distribution in the domain.Therefore,the need to develop techniques to provide solutions for such problems and estimate the inverse mass flux becomes imperative.Adaptive state estimator(ASE)is increasingly becoming a popular inverse estimation technique which resolves inverse problems by incorporating the semi-Markovian concept into a Bayesian estimation technique,thereby developing an inverse input and state estimator consisting of a bank of parallel adaptively weighted Kalman filters.The ASE is particularly designed for a system that encompasses independent unknowns and/or random switching of input and measurement biases.The present study describes the scheme to estimate the groundwater input contaminant flux and its transient distribution in a conjectural two-dimensional aquifer by means of ASE,which in particular is because of its unique ability to efficiently handle the process noise giving an estimation of keeping the relative error range within 10%in 2-dimensional problems.Numerical simulation results show that the proposed estimator presents decent estimation performance for both smoothly and abruptly varying input flux scenarios.Results also show that ASE enjoys a better estimation performance than its competitor,Recursive Least Square Estimator(RLSE)due to its larger error tolerance in greater process noise regimes.ASE's inherent deficiency of being slower than the RLSE,resulting from the complexity of algorithm,was also noticed.The chosen input scenarios are tested to calculate the effect of input area and both estimators show improved results with an increase in input flux area especially as sensors are moved closer to the assumed input location.     

Outlining a stepwise,multi-parameter debris flow monitoring and warning system: an example of application in Aizi Valley,China

In recent years, the increasing frequency of debris flow demands enhanced effectiveness and efficiency of warning systems. Effective warning systems are essential not only from an economic point of view but are also considered as a frontline approach to alleviate hazards. Currently, the key issues are the imbalance between the limited lifespan of equipment, the relatively long period between the recurrences of such hazards, and the wide range of critical rainfall that trigger these disasters. This paper attempts to provide a stepwise multi-parameter debris flow warning system after taking into account the shortcomings observed in other warning systems. The whole system is divided into five stages. Different warning levels can be issued based on the critical rainfall thresholds. Monitoring starts when early warning is issued and it continues with debris flow near warning, triggering warning, movement warning and hazard warning stages. For early warning, historical archives of earthquake and drought are used to choose a debris flow-susceptible site for further monitoring. Secondly, weather forecasts provide an alert of possible near warning. Hazardous precipitation, model calculation and debris flow initiation tests, pore pressure sensors and water content sensors are combined to check the critical rainfall and to publically announce a triggering warning. In the final two stages, equipment such as rainfall gauges, flow stage sensors, vibration sensors, low sound sensors and infrasound meters are used to assess movement processes and issue hazard warnings. In addition to these warnings, community-based knowledge and information is also obtained and discussed in detail. The proposed stepwise, multi-parameter debris flow monitoring and warning system has been applied in Aizi valley China which continuously monitors the debris flow activities.     

Influence of Azores High pressure on Middle Eastern rainfall

Several studies demonstrate that North Atlantic Oscillation influences variability of climate over Middle East. We use the centers of action approach for the study of winter rainfall variability over Middle East, taking into account variations in the components of the North Atlantic Oscillation, the Azores High and the Icelandic Low pressure systems. The results show there is a negative relation between the interannual variations of winter rainfall over Middle East and Azores High pressure. The east–west shifts of Indian Ocean high pressure has also impact on precipitation over Middle East, there being more precipitation when the Indian Ocean High shifts eastward versus when it is westward. We present a regression model for Middle East precipitation in which the Azores High pressure and the Indian Ocean High longitude are independent variables and it explains 40 % of the variance of precipitation during 1952–2002. Furthermore, the ongoing decrease in winter precipitation over the Middle East is attributed to the increasing pressure of the Azores High over the same period.