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Petroleum Hydrocarbon Pollution of Mangrove Swamps: The Promises of Remediation by Enhanced Natural Attenuation

Problem statement: The Remediation by Enhanced Natural Attenuation (RENA) is currently being used as a cleanup technology in polluted environments in the Niger Delta and other parts of the globe. The effectiveness of RENA as a remediation technology in the most recent time has been challenged by few authorities. The deleterious effects of pollutants on the environment have led to increased awareness and vigilance against contamination of the Niger Delta environment. Bio remediation which has been defined as biological response to environmental abuse has continued to receive research attentions across the globe. This study addresses issues against the RENA and recommended ways forward. Approach: The review paper studied published articles and Oil companies routine practices of managing petroleum hydrocarbon polluted Environments including mangrove swamps from 1970 till date. The Remediation by Enhanced Natural Attenuation (RENA) is currently being used as a cleanup technology in polluted environments in the Niger Delta including mangrove ecosystems. Results: The study made inputs on the controversial issues around RENA technology and recommended certain ways forward. This revision also reported the ways of managing the concerns raised against RENA. Conclusion/Recommendations: Oil firms, remediation contractors and consultants using this RENA approach should employ strict monitoring during the process and also adhere strictly to standard practices and the mitigation measures for all the cases against RENA as documented in this review study. This is to ensure the achievement of Sustainable Development.

Effectiveness of Agricultural Extension Activities

Problem statement: Jordan�s agricultural extension service is seriously under-staffed and its effectiveness is consequently compromised. Reservations are being expressed about the performance and capability of the agricultural extension system in Jordan. The performance of this sector has been disappointing and has failed to transfer agricultural technology to the farmers. The main objective of this study is to assess the effectiveness of Jordan�s agricultural extension services. Approach: The effect of extension services on olive productivity in the study area was investigated. A total number of 60 olive producers were selected to be interviewed for this study. This number was enough to achieve the study objectives. The interviewed producers were distributed almost equally within olive production locations in the study area. The sample obtained through the simple random sampling technique. The two groups had been chosen and distributed randomly into an experimental group (30 farmers; 10 for each source of extension service) and control group (30 farmers). The experimental group received extension services and the control group received no extension services. Two interview-cum-structured questionnaires were designed and used to collect information and data for this study. The first instrument was designed for farmers who received extension services and the second from farmers who received no extension services. Another questionnaire was designed for administrators of extension organizations concerned with providing extension services to farmers. To find the differences that may exist between two studied groups, One Way Analysis of Variance (ANOVA), t-test and LSD test via Statistical Package for Social Sciences software (SPSS) were used. The average net profit obtained from an area of one dynamo of olive farm was the main item to be considered in determining the effectiveness of agricultural extension activities. Results and Conclusion: The results of the study revealed that the net profit of farmers who received extension services is almost the same as those who do not receive any extension services. The provided extension services made no difference in the achievement of farmers regarding their production and consequently their net profits. The three main investigated sources of extension services provide inadequate and less effective extension services. To overcome most of the obstacles facing extension programs in Jordan the government should impart extensive in-service agricultural trainings to train the extension personnel to cope with the growing needs of farmers. The establishment of field demonstration sites, pilot sites on farmers� fields around the demonstrations is another important issues to be covered.

Evaluation of Vegetables Farmers Participation in Agricultural Extension Activities

Problem statement: Farmers's participation in extension activities is one of the most important issues facing extension providers in Jordan. The determination of the reasons that prevent farmers from participation in some extension activities is another problem. This study was conducted to evaluate the level of vegetables farmers� participation in agricultural extension activities in the Dear Alla area of Jordan and to investigate the reasons that prevent farmers� participation in agricultural extension activities. Approach: The study investigated farmers� socioeconomic characteristics, extension activities, farmers� opinion concerning the activities and the degree of participation of farmers regarding the conducted activities. The study was conducted to cover the Dear Alla area. The dear Alla area is one of the most important vegetable production areas of the Jordan Valley. The population of this study included all the vegetable farmers in this area. Results: The sample obtained through the simple random sampling technique. A total number of 320 vegetable farmers were selected. A structured questionnaire was designed to obtain information from farmers. The questionnaire consisted of two main parts; the first part was related to personal and socioeconomic characteristics of the sample individuals. The second part was related to extension activities. Conclusion/Recommendations: High, medium and low levels of interviews farmers� participation in agricultural extension activities were noticed. Three activities resembled 43% of the total investigated activities (7 activities) were high in the degree of farmers� satisfaction indicating high levels of farmers� participants. Other three activities were with medium level and also resembled 43% of the total investigated activities. The remaining activity was low in participation and resembled 14% of the total investigated activities. The date of the activity is not suitable for farmers and the preoccupation with another concern or job resembled 60% of the reasons for farmers not to participate in agricultural extension activities. The other three reasons: (Does not know the date of activity, unwillingness to participate and activities do not meet their needs) resembled the remaining 40% of the reasons for the interviewed farmers not to participate. In the light of the findings of the study extension activities should be planned with full involvement of farmers to increase their level of participation and using local leaders as contact farmers could enhance farmer participation and will be beneficial in this regard.

Assessment of the Maize (Zea mays)-Mucuna (Mucuna deeringianum Bort) Agroecosystem

Problem statement: In Selva de Chiapas, Mexico, the traditional farming technique of slash-fell-burn used on hillside fields has caused severe soil deterioration. Consequently, indigenous farmers reacted by developing several agroecological practices that improve the physical, chemical and biological fertility of the soils. Standing out among these techniques is the use of Mucuna (Mucuna deeringianum Bort.) in rotation with maize (Zea mays L). Approach: The objective of this study was to determine the effect of the maize-mucuna system on soil fertility, ecosystem diversity and maize crop yield. The study was conducted in the Tulija Valley, Chiapas, in the autumn-winter growing season (November-April). A completely random design was applied to four periods of consecutive maize-mucuna cropping (0, 5, 10 and 15 years) in order to analyze the most significant variables related to soils, weeds, seed bank and yield. Results: The results obtained reveal the higher nutrient concentration in the topsoil (0-15 cm) and better crop yield in the treatments with Mucuna rotation. No direct relationship was observed between nutrient content and duration of maize-mucuna system usage. However, the diversity of weeds and similarity of species both diminished where this farming method was used. Conclusion/Recommendations: It was determined that the use of the maize-mucuna agroecosystem helps to increase and maintain agroecological sustainability, supporting this practice that has been adapted and utilized by indigenous Choles for more than 30 years.

The Functional Effect of Kaempferia Parviflora on Ischemic Stroke in Rats

Problem statement: Oxidative stress has been implicated as important factors in the pathogenesis of cerebral ischemia-induced behavioral deficits particularly memory. Growing attention is being paid to traditional medicinal plants possessing antioxidant activity, as they have been proved therapeutically/prophylactically fruitful against stroke condition. Present study provides evidence of the neroprotective effects of a Thai traditional herb, Kaempferia Parviflora (KP) extract, against oxidative stressrelated brain damage and memory deficit induced by focal cerebral ischemia in rats. Approach: Male Wistar rats were orally given the ethanolic extract of KP at doses of 100, 200 and 300 mg kg^-1 BW once daily continually for 14 days before and 7 days after right Middle Cerebral Artery occlusion (MCAO). Spatial memory was evaluated using the Morris water maze test at 7 days after MCAO and then rats were sacrificed for determining the survival neurons and biochemical markers of lipid peroxidation in the hippocampus. Results: Only KP at 200 mg kg^-1 BW could ameliorate oxidative injuries induced by cerebral ischemia by decreasing the lipid peroxidation leading to the enhanced neuron densities in all areas of hippocampus, which in turn resulted in the improved spatial memory impairment. Conclusion: Overall, KP supplementation may be advantageous to the reduction of oxidative damage and for the improvement of memory deterioration in stroke or vascular dementia.

Validation of the Ceres-Wheat for Prediction of Wheat Varieties in Irrigation and Terminal Drought Stress

Problem statement: Crop growth models have many potential uses for crop managements. Approach: In order to evaluation of CERES-Wheat model on five varieties of winter wheat in Karaj weather condition in Full Irrigation (FI) and Stop Irrigation (SI) after flowering until final growth stage an experiment conducted in shape of split plot in based on randomize complete block design with four replicate in research field Islamic Azad university of Karaj branch in 2009-2010. Two irrigation levels located in main plot and cultivars as sub plot. In this study simulation of some traits such as Grain Yield (GY), Biomass (B) and Leaf Area Index (LAI) was evaluated by use of CERES-Wheat model. Results: According to results, model was successful in simulation of traits whole under two irrigation treatments. Rate of coefficient of correlation (R2) was low in regression curve of measured versus simulated for traits of LAI. Model simulated GY with high vigor for both irrigation conditions. Variation dimension of R2 in FI and SI obtained 0.8089-0.8097 and 0.8087-0.9504, respectively. Variation dimension of Wilmot coefficient (d) FI and SI was 0.65-0.74 and 0.58-0.74, respectively. Simulation precise in SI was lower than FI. We could after evaluation and calibration model by means of experimental replication and reduce of Root Mean Square Error (RMSE) as a result used for research objective management programming in Karaj area. Conclusion: The results of CERES-Wheat model assessment in this research indicated that this model in full irrigation and discontinuing the irrigation after flowering stage have appropriate and good accurate, simulation of seed yield and biomass but has simulated the leaf area index well only in full irrigation conditions.

Agro-Process Intensification through Synthetic Rhizosphere Media for Nitrogen Fixation and Yield Enhancement in Plants

Problem statement: In order to combat global warming and the emerging Food, Energy and Water shortages (FEWs), several approaches have been adopted, including genetic engineering and farming practices. Biomass based energy technology will further stress food and water resources and hence novel holistic approaches to FEWs should be designed. Approach: A novel technique (Agro-Process Intensification, A-PI) which simultaneously addresses FEWs in general and food production in particular was described. The technique was based on the enhancement of multiple interactions between plant roots, water, nutrients and bacteria using soil additives in the form of micro-bioreactors which allow plant root growth through them thus generating a micro-environment acting as a Synthetic Rhizo Sphere (SRS). The SRS-media was a nano-structured micro-porous crosslinked, elastic, ionic and highly hydrophilic polymer, facilitating the efficient use of water and nutrients as well as nitrogen fixation in legumes. Results: SRS media, with or without bacteria, was prepared, characterized and used in greenhouse experiments. Grass, for which the enhancement was well above 200% under water stress, was used to evaluate the mechanism of A-PI. The pea plant was used to demonstrate the intensification achievable by biologically active micro-bioreactors in which nitrogen fixing bacteria, Rhizobia, were supported within the SRS-media. Biologically active SRS-media enhanced the plant root infection by nitrogen fixing bacteria and increased both crop yield (ca. 70%) and mineral content. Conclusion/Recommendations: A-PI is achieved principally through the elimination of the random nature of the root/water/nutrient/microorganism interactions. The association of SRS-media with plant roots provides a unique and efficient delivery technique for water and nutrients while protecting beneficial bacteria within the SRS for infection enhancement. Focus on the understanding of the molecular mechanisms of yield enhancement and SRS formation as well as performance in field trials, especially in marginal land under water and nutrient stress, are recommended.

Simulation of Wheat Cultivar Response to Irrigation Treatments using of CERES-Wheat Model

Problem statement: Crop models are used as tools for enhancing agricultural research through the identification of gaps in knowledge as well as by providing support for decision making in agricultural planning. Approach: In order to evaluation of CERES-Wheat model on five cultivars of winter wheat under Karaj weather condition in Full Irrigation (FI) and Terminal Irrigation at Flowering (TIF) an experiment conducted in form of split plot in based on randomize complete block design with four replicate in research field Islamic Azad university of Karaj branch in 2009. Results: Two irrigation levels located in main plot and cultivars as sub plot. In this study simulation of some traits such Grain Yield (GY), Leaf Dry Weight (LDW), Plant Height (PH), Biomass (B), Leaf Number per plant (LN) and Leaf Area Index (LAI) evaluated by use of CERES-Wheat model. According to simulation results, model was successful in simulation of traits whole under two irrigation treatments. Rate of R² was low in regression curve of measured versus simulated for traits of LAI and LDW. Model simulated GY with high vigor for both irrigation conditions. Conclusion/Recommendations: Variation dimension of R² in FI and SI obtained 80.89-80.91 and 80.88-81.01, respectively. The variation dimension of Wilmot coefficient (d) FI and TIF is 0.73-0.75 and 0.61-0.72, respectively. Simulation precise in TIF is lower than FI. We can after evaluation and calibration model by means of experimental replication and reduce of Root Mean Square Error (RMSE) as a result used for research objective management programming in Karaj zones. We proposed for increasing predicting precise by model must be determinate genetic coefficient correctly and soil data and weather data supplied in experimental filed.

Simulation of Soybean Growth under Sowing Date Management by CROPGRO Model

Problem statement: Always because of weather change, determine of optimum sowing date in each zone is difficult. Dynamic models can help us for solving this problem. In order to evaluation of soybean simulation by using of CROPGRO-Soybean model at four sowing date in field research of Azad university of Karaj branch a field experiment conducted in form of split plot in based on randomize complete block design with four replication in 2009s. Approach: At this experiment simulation of some traits such Leaf Area Index (LAI), Leaf Dry Weight (LDW), Stem Dry Weight (SDW) and Biomass (B) evaluated for cv. Williams using of CROPGRO-Soybean. According to results, model was successful in the traits simulation, because of high Wilmot coefficient produced (0.6), 20 days after planting to the end of the growth duration. Results: Model explained well stem dry weight, as correlation coefficient in each sowing date was significant (p<0.01). Simulation precision for biomass was suitable, as coefficient differentiation was significant (p<0.01) for first to fourth sowing date (S1-S4) 0.889, 0.986, 0.909 and 0. 796, respectively. These statistic parameters designated high ability of model for simulation of some traits measured in soybean for four sowing date management. Conclusion: We can use by model for sowing date management of soybean in Karaj climate condition, of course after repetitions of experiment and doing of model calibration. We proposed that soil and weather data measured in each place of experience and also plant morphology parameter measured precisely because this help to us for obtaining of objects.

Inulinase Production by Penicillium citrinum ESS in Submerged and Solid-State Cultures

Problem statement: This work reports the Penicillium citrinum ESS strain as a new source of inulinase (2,1-β-D fructanhydrolase, E.C. 3.2.1.7). Approach: The enzyme was produced in both, Solid-State (SSC) and Submerged Culture (SmC) using a basal medium added either with inulin or sucrose (5 gL^-1). Results: The culture grew faster in SmC than in SSC with both carbon sources; however, yields of inulinase activity per gram of biomass were higher in SSC (1,658,237.28 for inulin and 66598.96 for sucrose) than in SmC (441.05 for inulin and 183.91 for sucrose). Conclusion: The highest inulinase production was obtained by SSC, either with inulin or sucrose, reaching values of 6650 and 2970 U/L respectively. In contrast, in SmC were obtained higher levels of inulinase activity (2241 U/L) with sucrose as carbon source (24 h), while with inulin, the enzyme production was negatively affected and retarded.