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Microbial Dynamics in Salt Affected Soils

Thesis Info

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Author

Shah, Syed Asif

Program

PhD

Institute

The University of Agriculture

City

Peshawar

Province

KPK

Country

Pakistan

Thesis Completing Year

2013

Thesis Completion Status

Completed

Subject

Applied Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/1289

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726638925

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Soil salinity is a worldwide problem which not only influences the physical and chemical properties of soil but may also seriously affect the microbiological properties of soil. This project was undertaken to assess the behavior of various microbiological properties of soil in relation to salinity in a series of incubation and pot experiments during 2009-12. Initially the soil microbiological properties of thirty naturally occurring diverse salt affected soils were determined. Based on the results of preliminary experiments, further experiments were conducted to evaluate the effect of NaCl and MgCl 2 induced salinity on N dynamics and soil microbial activity in soil. Finally, a pot experiment was conducted to assess the effect of important amendments such as pressmud, gypsum and farmyard manure, which are normally used for the reclamation of salt affected soils, on growth of wheat and maize and on various microbial attributes in a highly saline-sodic soil (EC 20.3 dS m -1 ). In addition, some bacteria and fungi were isolated from a highly saline-sodic soil, and the effects of same organisms were also tested in the above experiment. For experiment 1, soil samples at 0-20 cm were collected from various salt affected soils ranged in salinity from EC < 4.0 to 32 dS m -1 in November 2009. The samples were analyzed for soil microbiological (such as microbial biomass-C, microbial biomass-N, N mineralization, nitrification, rate of soil respiration) and chemical properties (such as pH, EC, soluble Ca+Mg, soluble Na, SAR (sodium adsorption ratio), ESP (exchangeable sodium percentage), carbonates, bicarbonates, chloride). The results showed that almost all microbial indices including microbial biomass-C (MBC), microbial biomass-N (MBN), basal soil respiration, nitrification and net N mineralization were negatively correlated with increasing salinity (r = -0.89, -0.74, - 0.79, -0.64 and -0.57 respectively). The results further showed that the depressive effects of SAR and ESP on various soil microbial indices were much stronger than that of carbonates and bicarbonates. Both NaCl and MgCl 2 induced salinity significantly reduced the rate of CO 2 evolution and N mineralization during all xiiiincubation periods. The depressive effects increased with increase in salts level. The NaCl induced salinity depressed cumulative CO 2 production by about 80% and N mineralization by 50% during 40 days of incubation. Whereas MgCl 2 induced salinity decreased cumulative CO 2 production by 95% and N mineralization by 81% during 30 days of incubation. These results suggested that the impact of MgCl 2 salinity on microbial indices was stronger than that of NaCl. The amendment of saline-sodic soil with pressmud, gypsum and farmyard manure (FYM) significantly improved the rate of CO 2 evolution, N mineralization, microbial biomass-C and microbial biomass-N. The effects were more pronounced with combined application of pressmud with farmyard manure or gypsum. It was also evident that the effect of pressmud + FYM was further improved with microbial inoculation of microbial isolation from highly salt affected soil. Organic matter decomposition generally increases the production of CO 2 and liberation of H + ions. The H + ion enhance the dissolution of CaCO 3 and releases more Ca to replace Na from clay particles and thus helps in the reclamation of saline-sodic soils. Both wheat and maize seeds failed to germinate under the prevailing saline-sodic conditions despite repeated re-seeding and thus no data was generated in this respect. These results suggested that all microbial indices decreased significantly with increasing salinity levels indicating that soil microorganisms were sensitive to different types of salinity. Thus, salinity is a stress factor and can reduce microbial diversity and control microbial abundance, composition and functions. Although, amendments of saline-sodic soil with organic sources (such as FYM, pressmud) substantially improved microbial attributes they did not enable the germination and survival of wheat and maize sown in the soil. Nevertheless the evidence suggests that organic matter may play significant role in the amelioration of saline-sodic or sodic soils.
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بھول بھی کیسے سکتے ہیں

بھول بھی کیسے سکتے ہیں

وہ تمام دن وہ تمام غم جو گزر گئے

ہمیں یاد ہیں ہمیںیاد ہیں

وہ عجیب لوگ وہ قافلے

جو نہ رک سکے نہ بھٹک سکے

ہمیں یاد ہیں ہمیں یاد ہیں

(بھول بھی کیسے سکتے ہیں )

 

 

ذخیرہ اندوزی سے متعلق ہندومت، یہودیت اور اسلام کے احکام کا جائزہ

Hoarding is considered (Ihtikar) very abhorring and objectionable. It is the practice of keeping something in store and not bringing the same to the market so that prices may rise owing to this artificial dearth of supply in the market. Each religion of the world has agriculture rules. In these, rules about Hoarding play an important role. In non Semitic religions Hinduism is the largest religion of the world. Similarly in Semitic religions Islam is the second and Judaism is considered in third stage. All these three religions and there followers have good relation with agriculture. But among this, Islamic rules considers one of the best rules in the world. Because Hinduism agriculture rules affected by cast system and the other side Judaism rules is affected by customs and traditions. But still there are some points on which Hinduism, Judaism and Islam are completely supporting each others. Hoarding rules is one of them. This paper is consisting on hoarding rules in Hinduism, Judaism and Islam.

The Job Satisfaction of District Officers

Organizations expect involvement and commitment from their workforce to create esprit de corps for the realization of corporate as well as individual objectives. However, worker’s attitude (involvement and commitment) depends on his/her satisfaction from different aspects of the organization as related to the employees. Employee’s satisfaction or ‘Job Satisfaction’ therefore determines the degree to which a worker will be involved in and committed to any job/work. Several organizational dimensions have been identified as the predictors of job satisfaction but pay, work, supervision, promotion, work environment and co-workers are widely researched independent variables that have been studied over and over again (job-related factors). In the background of these instant variables, organizational structure, policies and broader social context play dominant role in the variation of job satisfaction (organization related variables). Finally, the personal characteristics of employees are also responsible to explain the job satisfaction of the workers in any organization (personal features). Job satisfaction is the degree of match and mismatch between whatever is expected by the employee from the organization and what he/she gets in reality. The worker expectations are the motivators which, if fulfilled, motivate the employee to get involved and show commitment. Thus, what motivates a worker is the predictor of his job satisfaction. According to the Maslow’s hierarchy of needs, job satisfaction of those employees who need to meet their primary needs depends on the fulfillment of primary motives. And those at the higher levels of motivation can be satisfied only when their8/193 higher level motives like status, recognition, and self-actualization are addressed by the organization. For example, workers with high level motives cannot be motivated or satisfied with the fulfillment of low level needs. One who needs high profile status cannot feel happy (neither motivated nor satisfied) with an increase in pay only. Although job, organization and person related variables are universal in their existence as predictors of job satisfaction however, they all ‘read’ differently from person to person, job to job, organization to organization and location to location. The same factors operate in every study of job satisfaction but their impact on workers’ contentment and performance vary significantly in multiple manners. Given this, neither the same explanation/definition can portray all the situations nor the single solution model can be implemented everywhere. There is need to understand every individual organizational situation separately in terms of job, organization and person related factors. These factors hold unique attributes in every employee and work situation and must be tapped by the researchers so that a ‘local’ definition of ‘job satisfaction’ could be developed to figure out a ‘domesticated solution’ for addressing satisfaction problems. A huge research is going on to explore the issue of job satisfaction of top management or executives, managers, supervisors, and the staff in different countries, organizations and situations. The findings from developed and developing nations match in several aspects but they also differ in many dimensions. For example, in advanced countries, high level motivation factors are more responsible for job satisfaction than in the developing states9/193 where job satisfaction still depends more heavily on the primary and middle level of factors of motivation. To cut short, the understanding of ‘job satisfaction’ as an issue for developing countries (in public or private sector organizations) is only possible if local research is conducted to record the nature, intensity and variety of job, organization and employee related characteristics. This local knowledge can give real touch of the ‘native problem’ thereby enabling the concerned researchers and authorities to sort out a real picture of the problem. Furthermore, the localized version of the problem is only logical option for devising a solution that is compatible with the local work attitudes and environment. The research shows that there is big variation between the job satisfaction of public and private sector employees with common belief that public sector employees are less satisfied than those working in private organizations. Similarly, job satisfaction varies within public organizations across different departments. Abdul Sattar Khan PhD scholar in Management Studies Department of Public Administration, GU, DIK, KPK, Pakistan