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Shah Z.,University of Peshawar | Ahmad S.R.,ARI Inc | Rahman H.U.,University of Peshawar
Pakistan Journal of Botany

The objectives of this study were to assess the influence of green manure legumes and N fertilizer on soil microbial biomass and activities in rice (Oryza sativa) -wheat (Triticum aestivum) system. Soil samples (0-15 cm) were collected from field experiment established in 2001 involving mungbean (Vigna radiata), cowpea (Vigna unguiculata), soybean (Glycine max), sesbania (Sesbania rostrata), pigeonpea (Cajanus cajan) and guar (Cyamopsis tetragonoloba) as green manure in rice-wheat system in Peshawar valley, Pakistan. The results showed that the green manure legumes and N fertilizer application significantly increased the microbial biomass and activities in rice-wheat system. The average improvement gained from the green manure legumes relative to (fallow-based-rice-wheat) FRW, was 1.79 times for microbial activities, 1.70 times for microbial biomass-C (MBC), 1.49 times for microbial biomass-N (MBN), 1.82 times for C mineralization, 1.92 times for N mineralization, 3.36 times for bacterial population and 1.46 times for fungal population. The average improvement gained from N fertilizer (+N) relative to no N unfertilizer (0N), was 1.40 times for microbial activities, 1.17 times for MBC, 1.29 times for MBN, 1.42 times for C mineralization, 1.45 times for N mineralization, 1.17 times for bacterial population and 1.42 times for fungal population. Our results thus suggest that the microbiological attributes proved to be highly responsive and sensitive to the beneficial influence of green manure legumes in rice-wheat system and can be used as indicator of soil quality. Source

Shah Z.,Khyber Pakhtunkhwa Agricultural University | Ahmad S.R.,ARI Inc | Rahman H.U.,Khyber Pakhtunkhwa Agricultural University
Pakistan Journal of Botany

This study was aimed to attempt if we can fit a green manure legume in the gap between wheat harvest and rice plantation for sustainable rice (Oryza sativa) -wheat (Triticum aestivum) system. The effect of six green manure legumes viz. mungbean (Vigna radiata), cowpea (Vigna unguiculata), soybean (Glycine max), sesbania (Sesbania rostrata), pigeonpea (Cajanus cajan) and guar (Cyamopsis tetragonoloba) was assessed on rice yields and soil organic fertility in rice-wheat system for three consecutive years (2001/02-2003/04) at Agriculture Research Institute, Tarnab, Peshawar (Pakistan). The paddy and straw yields of rice were significantly increased by all green manure legumes during all the three years. However, on average, the greatest paddy and straw yields were recorded for cowpea and sesbania. The N uptake in rice was also significantly increased by legumes. However, the greatest N uptake occurred in the sesbania plot. Significantly positive effects of green manure legumes were also observed on soil organic matter, total N and mineral N relative to the fallow-based rice-wheat system. Our results suggest that the gap between wheat harvest and rice plantation can be effectively used to grow any green manure legume in general and sesbania or cowpea in particular in Khyber Pakhtunkhwa for sustainable rice-wheat system. Although this technology was tested in Peshawar valley, it has equal applications any where in the rice-wheat system. Source

The movement toward an astrosociological curriculum has slowly made headway since the incorporation of the Astrosociology Research Institute (ARI) in May 2008. Much of the effort during the first two or three years involved the continued articulation of the definition and relevance of the field, which still continues to some extent, but the shift in orientation for ARI has begun to move toward the implementation of educational programs and the execution of astrosociological research. ARI's Astrosociology in the Classroom program exists to develop courses that cover the various astrosociological subfields, including its first objective of creating an Introduction to Astrosociology course for undergraduate students. The focus of astrosociology centers on the human dimension of space exploration, settlement, and other related activities; that is, how the human element interacts with space. This interaction between space and society/humankind, known as astrosocial phenomena - and defined as social, cultural, and behavioral patterns related to outer space - is the focus of astrosociology. As a multidisciplinary field, it includes the social and behavioral sciences, the humanities, and the arts. The importance of astrosociology lies in the fact that it epitomizes the underrepresented half of the entire body of knowledge needed to understand and sustain the potential of an increasingly strong relationship between humankind and space, with the other half consisting of the STEM fields and disciplines. The intent of this essay is to provide potential astrosociology students with a survey of the important subfields so they can make informed decisions about whether to pursue the field during its early stages within academia. Potential students should be aware that they would become important shapers of astrosociology just by their very study of astrosociological issues. Source

It is easy to take a well-functioning complex system for granted, even when we do not quite understand how it will work in great detail before starting it up for the first time, or exactly how it works thereafter (given its complexity). At the system level, the normal operation of the space habitat can result in accidents. On the personal level, complacency, and the false sense of security that comes with it, become the enemy quite quickly and usually without much - or any - notice. Workers do not intend to overlook important signs of behavioral aberrations or equipment malfunctions, but they may lose their sharpness and objectivity over time. In isolated settings, a variety of causes can result in devastating accidents, which may result in illnesses, injuries, and deaths. In the worst circumstances, within the confines of a space habitat or spacecraft, an entire population could be lost. Oil refineries provide a good, though obviously imperfect, analogy for the space habitat. Refineries are complex systems that transport and process oils and fuels at varying steps during the refining process within a complex system. Space habitats represent even more extreme closed systems. There is often no escape, as the habitat provides the atmosphere and other elements necessary for survival. Inhabitants of space habitats must avoid the types of accidents that have occurred in refineries on Earth if they expect to survive as individuals and as a social system. Submarines present a better analogy of a closed system. A challenge that never disappears relates to the possibility that the system may operate on a "normally" on one day and then malfunction on another day for no apparent reason. Another challenge among members of a space society is to avoid complacency, because an imminent failure may occur at any time. Yet another challenge is to avoid engaging in health and safety violations in order to serve expediency due to pressures exerted by superiors and for other reasons. Maintenance workers and others must also avoid succumbing to peer pressure based on a variety of rationales. We can learn much from the existing social scientific health and safety literature. Theoretical application of these lessons to space habitats presents a difficult task for the astrosociologist before we build these extraterrestrial physical and social structures. These findings need to become part of the planning process in the future, but we must understand them now rather than after we place human beings at risk in hostile space ecologies. This article takes an initial, and thus cursory, look at these issues related to one form of deviance, hoping to serve as an impetus to provoke future research into this largely unexplored area. © 2011 Published by Elsevier B.V. Selection and/or peer-review under responsibility of Institute for Advanced Studies in the Space, Propulsion and Energy Science. Source

As with any academic field, astrosociology allows for an endless number of competing theoretical models and hypotheses. One possible theoretical model is presented here that starts with the premise that even the most advanced societies today are extremely far from achieving a spacefaring status. The most advanced nation states are, in fact, space-capable societies because they have the capacity to send cargo and humans into low Earth orbit and beyond. However, their social structures and cultures lack fundamental characteristics that would allow for their designation as spacefaring societies. This article describes the characteristics of a theoretical spacefaring society and argues that getting there from our current status as space-capable societies is a long and arduous process, and it is not a definite outcome whatsoever. While a continuum is offered, it represents an imprecise path that can retrograde or fall apart at any time. Thus, this theoretical model provides one possible series of an unfolding of events that result in the creation of characteristics of the social fabric that may result in movement along the continuum toward a spacefaring society. Movement along the continuum results in an accumulation of coordinated spacefaring characteristics for a given society. Simultaneously, strictly terrestrial characteristics disappear or transform themselves into hybrid forms that include spacefaring features. This exercise demonstrates that this theoretical exercise has a number of benefits for astrosociologists conducting research in the area of spacefaring theory. Moreover, it makes the case for the idea that the study of the theoretical transformation from a space-capable to a spacefaring society includes implications for current and future 1) space policy in the public sector and 2) corporate decision-making related to space in the private sector. © 2011 Published by Elsevier B.V. Selection and/or peer-review under responsibility of Institute for Advanced Studies in the Space, Propulsion and Energy Science. Source

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