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Home > An Investigation into the Refinement of Restoration Techniques for the Rehabilitation of Natural Thorn Forest Species on a Derelict Site

An Investigation into the Refinement of Restoration Techniques for the Rehabilitation of Natural Thorn Forest Species on a Derelict Site

Thesis Info

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External Link

Author

Sharif, Faiza

Program

PhD

Institute

Government College University

City

Lahore

Province

Punjab

Country

Pakistan

Thesis Completing Year

2003

Thesis Completion Status

Completed

Subject

Natural Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/1190

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676725473298

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A bare salt-affected land was selected in the vicinity of a remnant grove of thorn forest community at Harappa archaeological site with the objective of rehabilitating minimum viable populations of thorn forest species. Monitoring of previously planted trees revealed spatial differences in species establishment with sites showing good, moderate and poor survival and growth. In order to successfully restore the site a complete set of experiments was designed, that based on in-depth analysis of microclimatic factors, species tolerance limits and fertilizer amendments. The results revealed that restoration of native plant community required the identification and modification of environmental factors that were impeding or restricting ecosystem development at this site. They also showed that the area is not uniformly saline but can be divided into sites of low (EC e < 60 mS cm -1 ), moderate (60-85 mS cm -1 ) and high (> 85 mS cm -1 ) surface salinity. Analysis of replaced soil showed accumulation of salinity in plant pits at all the sites in general and at high salinity site in particular resulting in greater plant mortality at that site. Difference in micro-topography was causing greater salinity built-up in the pits at high salinity site especially by monsoon overflows resulting in high plant mortality. A pot experiment designed to check the response of individual species to salinity and fertilizers showed a negative linear relationship between plant growth and biomass characters as they decreased with increasing salinity levels and were enhanced with increasing fertility. All tree species seemed to be salt tolerant to varying degrees. EC e value at which dry matter production would be reduced to 50% as compared to un-fertilized control plants was highest for Salvadora oleoides followed by Prosopis cineraria, Tamarix aphylla and Capparis decidua under low fertility and this sequence of decreasing salt tolerance was maintained when plants were supplemented by fertilizers. An in-situ experiment was conducted using soil replacement, gypsum and inorganic fertilizers as amendments on the three salinity sites. Three years monitoring suggested that enhanced Nitrogen and Phosphorus nutrition had a positive effect on all growth variables as availability of both in the soil was limiting. The effect was more pronounced at site of low salinity and in more tolerant S. oleoides and T. aphylla as compared to the other two species. Moreover remedial measures for the xivrevegetation of highly saline patches were experimented with nutritional amendments in combination with surface modification at high salinity site. Incorporation of farmyard manure (FYM) with physical barriers generated the greatest revegetation success in all species and was not only found to be biologically sound but also economically feasible restoration treatment. A total of 705 trees have been successfully established out of that 481, 132, 57 and 35 are of S. oleoides, T. aphylla, P. cineraria and C. decidua, respectively. After initial fertilization and two years of supplemental irrigation the plants are now not required to be nurtured. Three out of four tree species have started producing seeds and many trees are now acting as nurse plants and are facilitating the establishment of other species under them. With the arrival of avian dispersers natural recruitment can now be seen at many places. Ecosystem function parameters are indicating that this restored area is on a trajectory towards a self-sustaining ecosystem. Recommendations derived from this study have been incorporated in the site management plan and have been successfully implemented for the rehabilitation of adjacent area. With the accumulation of both above and below-ground biomass as well as litter and other woody debris this juvenile forest is now sequestering carbon and is contributing towards building viable populations of thorn forest species at Harappa archaeological site. The populations of both S. oleoides and T. aphylla have now attained a safe number while increasing the number of individuals of P. cineraria by reclaiming more area and initiation of seed formation in this species will also assure its population viability.
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پروفیسر اصغر علی فیضی

پروفیسر اصغر علی فیضی
پروفیسر فیضی آکسفورڈ کے اعلیٰ تعلیم یافتہ تھے ان کااصل مضمون قانون تھا، مشرقی علوم وفنون میں بھی ان کودسترس تھی۔اسلامی قانون پران کی کتابیں حوالہ کی کتاب (Book of Reference)کی حیثیت رکھتی ہیں۔ عرصہ تک لاء کالج بمبئی کے پرنسپل رہے، انڈیا کے مصراور شام میں بھی سفیر رہے اورکشمیر یونیورسٹی کے وائس چانسلر بھی ہوئے۔ وزیٹنگ پروفیسر کی حیثیت سے کینیڈا، یورپ اورامریکہ کی متعدد یونیورسٹیوں میں لکچر دیے۔برہان کے خریدار شروع سے تھے اوراس کی بڑی قدر کرتے تھے، برہان کا کوئی مقالہ یانظرات ان کوزیادہ پسند آتاتھا تواس کی داد تحریراً دیتے تھے۔عرصہ سے ان کاکوئی خط نہیں آیاتھا۔بعض خانگی معاملات اورمسلسل ضعف وعلالت کے باعث سخت پریشان تھے۔ اب اچانک اخبارات میں ان کے انتقال کی خبر نظر سے گزری تودیرینہ تعلق کے باعث سخت صدمہ اورافسوس ہوا۔ اللھم اغفرلھما وارحمھما۔ [نومبر۱۹۸۱ء]

 

Perceptions of Sindhi Muslims Towards Exogamous Marriages: An Exploratory Study

It has been said that exogamous marriages tend to lead to language shift (Igboanus & Wolf, 2009 & Dumanig, David & Shanmuganathan, 2013). In an early study Gal (1978) found that Hungarian women marrying German men in the city of Oberwat had shifted to German to negate their peasant Hungarian ancestry and to move up the socio-economic ladder. Similarly, David and Dealwis (2011) found in their study of Malaysian Sindhi Hindus that exogamous marriages tend to lead to language shift but is not the only reason for the shift away from the heritage language. Therefore, before mixed marriages take place one should study perceptions of the speech community towards such marriages. In this exploratory study, the perceptions of Sindhi Muslims-men and women and from different socio-economic groups towards exogamous marriages are studied. With this objective, semi-structured interviews were conducted with ten Sindhi Muslim participants (four male adults and six female adults) who live in Karachi. The interviews were recorded, transcribed, coded and themes were generated after formal consent was obtained. The findings show that language choice in the home domain is shifting because of intercultural marriages. Also, such marriages are frequent among Sindhi community members with a high socio-economic status who live in cities. Gender plays an equal role too, as the women respondents showed mixed responses towards exogamous marriages while the male respondents had a more positive perception. Such views and perceptions may affect choice of marital partners and language choice in the home domain.

Physiological and Molecular Characterization of Two Genetically Diverse Spring Wheat Triticum Aestivum L. Cultivars for Salt Tolerance

Hydroponic experiments were conducted to appraise variation in the salt tolerance potential of two wheat cultivars (salt tolerant, S-24 and moderately salt sensitive MH-97) at different growth stages. Salinity stress caused a marked reduction in plant biomass and grain yield of both wheat cultivars. However, cv. S-24 was superior to cv. MH-97 in maintaining higher plant biomass and grain yield under saline stress. Furthermore, salinity caused a significant variation in different physiological attributes measured at different growth stages. For example, salt stress caused a marked reduction in net photosynthetic and transpiration rate in both wheat cultivars but to a varying extent at different growth stages. Higher photosynthetic and transpiration rates were recorded at the boot stage than at other growth stages in both wheat cultivars. The response of other gas exchange attributes was also variable at different growth stages. Salt sensitive wheat cultivar MH-97 was more prone to salt-induced adverse effects on gas exchange attributes as compared to cv. S-24. Salt stress caused considerable reduction in different water relation attributes of wheat plants. A significant reduction in leaf water, osmotic and turgor potentials was recorded in both wheat cultivars at different growth stages. Maximal reduction in leaf water potential was recorded at the reproductive stage in both wheat cultivars. In contrast, maximal turgor potential was observed at the boot stage. Salt-induced adverse effects of salinity on different water relation attributes were more prominent in cv. MH-97 as compared to those in cv. S-24. The integrity of PS II was greatly perturbed in both wheat cultivars at different growth stages and this salt-induced damage to PS II was more in cv. MH-97. A significant alteration in different biochemical attributes was also observed in both wheat cultivars at different growth stages. For example, salt stress caused a substantial decrease in chlorophyll pigments, ascorbic acid, phenolics and tocopherols. In contrast, it increased the endogenous levels of ROS (H2O2), MDA, total soluble proteins, proline, glycine betaine and activities of enzymatic antioxidants (SOD, POD, CAT, APX). These biochemical attributes exhibited significant salt-induced variation at different growth stages in both wheat cultivars. For example, maximum accumulation of glycine betaine and proline was recorded at the early growth stages (vegetative and boot). However, cv. S-24 showed higher accumulation of these two organic osmolytes and this could be the reason for maintenance of higher turgor than that of cv. MH-97 under stress conditions. The activities of various enzymatic antioxidants increased markedly in both wheat cultivars, particularly at the vegetative stage. However, cv. S-24 exhibited consistent increase in the activities of various enzymatic antioxidants, whereas, this phenomena occurred erratically in cv. MH-97 at different growth stages. Salt stress significantly increased the endogenous levels of toxic ions (Na+and Cl-) and decreased essential cations (K+ and Ca2+) in both wheat cultivars at different growth stages. Furthermore, K+/Na+ and Ca2+/Na+ ratios decreased markedly due to salt stress in both wheat cultivars at different growth stages and this salt-induced reduction was more prominent in cv. MH-97. Moreover, higher K+/Na+ and Ca2+/Na+ ratios were recorded at early growth stages in both wheat cultivars. It can be inferred from the results that wheat plants are more prone to adverse effects of salinity stress at early growth stages than that at the reproductive stage.