My Aim in Life

There are two things to aim at in life: first, to get what you want, and after that to enjoy it. Only the wisest of mankind achieve the second. Logan P. Smith People have set their own aim depending upon their abilities. Some people are doctors, engineers, Charter Accountants, pilots, teachers and many more. Our life is too short so we have to strive to attain our aim with all our hard work. The main objective for achieving the aim is to get material pleasures, mental happiness as well as satisfaction. Once a person chives his aim he can live a prosperous life.The mere act of aiming at something big, makes you big. Charcoal Nehru My aim in life is neither to collect money nor for fame. It is my desire to become a well-qualified doctor. I do not just wish to be an ordinary doctor. The world remembers with thankfulness the name of the man who gave to the world vaccination. The world will remember forever the man who gave us penicillin. As a doctor I want to serve the humanity. Don't ai m for success if you want it; just do what you love and believe in, and it will come naturally.David Frost have an ambition to do something in this world so, great as the doctors and the courageous founders did in the past. I would like to give the world some new drugs and injections that will cure some of the diseases that people are still suffering from. An aim in life is the only fortune worth finding. Robert Louis Stevenson know, my profession is very dignified and it will help me to get peace and satisfaction in life. It provides us best chances of service. Sympathy to human being is the sympathy to one own self. Quotations About this essay. Future favors the bold.An early death is better than an aimless life. A noble aim is simply a noble deed. My goal in life is to survive. Everything else is just a bonus. The greater danger for most of us lies not in setting our aim too high and falling short; but in setting our aim too low, and achieving our mark. Michelangelo The aim of ar t is to represent not the outward appearance of things, but their inward significance. Aristotle. Aim above morality. Be not simply good, be good for something. My Aim in Life There are two things to aim at in life: first, to get what you want, and after that to enjoy it. Only the wisest of mankind achieve the second. Logan P. Smith People have set their own aim depending upon their abilities. Some people are doctors, engineers, Charter Accountants, pilots, teachers and many more. Our life is too short so we have to strive to attain our aim with all our hard work. The main objective for achieving the aim is to get material pleasures, mental happiness as well as satisfaction. Once a person chives his aim he can live a prosperous life.The mere act of aiming at something big, makes you big. Charcoal Nehru My aim in life is neither to collect money nor for fame. It is my desire to become a well-qualified doctor. I do not just wish to be an ordinary doctor. The world remembers with thankfulness the name of the man who gave to the world vaccination. The world will remember forever the man who gave us penicillin. As a doctor I want to serve the humanity. Don't ai m for success if you want it; just do what you love and believe in, and it will come naturally.David Frost have an ambition to do something in this world so, great as the doctors and the courageous founders did in the past. I would like to give the world some new drugs and injections that will cure some of the diseases that people are still suffering from. An aim in life is the only fortune worth finding. Robert Louis Stevenson know, my profession is very dignified and it will help me to get peace and satisfaction in life. It provides us best chances of service. Sympathy to human being is the sympathy to one own self. Quotations About this essay. Future favors the bold.An early death is better than an aimless life. A noble aim is simply a noble deed. My goal in life is to survive. Everything else is just a bonus. The greater danger for most of us lies not in setting our aim too high and falling short; but in setting our aim too low, and achieving our mark. Michelangelo The aim of ar t is to represent not the outward appearance of things, but their inward significance. Aristotle. Aim above morality. Be not simply good, be good for something. My Aim in Life ARTICLE IN PRESS Microbiological Research 161 (2006) 93—101 www. elsevier. de/micres Changes in microbial and soil properties following amendment with treated and untreated olive mill wastewater Ali Mekki, Abdelha? dh Dhouib, Sami SayadiA Laboratoire des Bioprocedes,Centre de Biotechnologie de Sfax, BP: ‘‘K’’ 3038 Sfax, Tunisie ? ? Received 8 June 2005; accepted 15 June 2005 KEYWORDS Microbial community; Olive mill wastewater; Polyphenols; Soil respiration Summary We investigated the effect of untreated and biologically treated olive mill wastewater (OMW) spreading on the soil characteristics and the microbial communities.The water holding capacity, the salinity and the content of total organic carbon, humus, total nitrogen, phosphate and potassium increased when the spread amounts of the treated or untreated OMW increased. The OMW treated soil exhibited signi? cantly higher respiration compared to the control soil. However, the C-CO2/Ctot ratio decre ased from 1. 7 in the control soil to 0. 5 in the soil amended with 100 m3 haA1 of untreated OMW. However, it slightly decreased to 1. 15 in the soil amended with 400 m3 haA1 of treated OMW.The treated OMW increased the total mesophylic number while the number of fungi and nitri? ers decreased. Actinomycetes and spore-forming bacteria were neither sensitive to treated nor to untreated OMW. The total coliforms increased with higher doses of treated and untreated OMW. A toxic effect of the untreated OMW appeared from 100 m3 haA1. This toxicity was more signi? cant with 200 m3 haA1, where micro? ora of total mesophilic, yeasts and moulds, actinomycetes, and nitri? ers were seriously inhibited except for total coliforms and spore-forming bacteria. & 2005 Elsevier GmbH.All rights reserved. Introduction The olive mill wastewater (OMW) is a critical problem, especially in the Mediterranean area, where the olive cultivation is widespread and huge amounts of this ef? uent 30 millions m3 yA1 worldACorresponding author. Tel. /fax: +216 74 440 452. wide and 500 000 m3 yA1 in Tunisia alone, are annually produced (Sayadi and Ellouz, 1995; Casa et al. , 2003). This waste contains an enormous supply of organic matter, COD between 40 and 210 g dmA3 and BOD5 between 10 and 150 g dmA3 (Feria, 2000). Some characteristics of this materialE-mail address: sami. [email  protected] rnrt. tn (S. Sayadi). 0944-5013/$ – see front matter & 2005 Elsevier GmbH. All rights reserved. doi:10. 1016/j. micres. 2005. 06. 001 ARTICLE IN PRESS 94 are favourable for agriculture since this ef? uent is rich in organic matter, nitrogen (N), phosphorous (P), potassium (K) and magnesium (Mg). The organic fraction of this wastewater includes sugars, tannins, poly phenols, poly alcohols, pectins, lipids, and proteins (Mulinacci et al. , 2001; LesageMeessen et al. , 2001). For these reasons, increasing attention has been given to ? d the best methods to spread OMW on agricultural lands and to recyc le both the organic matter and the nutritive elements in the soil crop system. Moreover, agricultural irrigation with wastewater ef? uents became a common practice in arid and semiarid regions, where it was used as a readily available and inexpensive option to fresh water (Angelakis et al. , 1999; Oved et al. , 2001). Fresh OMW was used as a fertilizer in the horticulture and in the olive cultivation (Cox et al. , 1997; Ben Rouina et al. , 1999; Ammar and Ben Rouina, 1999; Cereti et al. , 2004).However, biodegradation of this waste in the nature is dif? cult because it contains a strong antibacterial effect exerted, by various phenolic compounds (Yesilada et al. , 1999; Sayadi et al. , 2000; Rinaldi et al. , 2003). Before its utilization in the irrigation, OMW was treated by several processes such as aerobic treatment, anaerobic digestion and composting process (Sayadi and Ellouz, 1992, 1995; Ehaliotis et al. , 1999; Paredes et al. , 2000; Kissi et al. , 2001; Marques, 2001; Casa et al. , 2003; D’Annibale et al. , 2004). Some Mediterranean countries established laws about soil capability to endure theOMW application, particularly in Italy (Law N1 574, 1996). The maximum amount of OMW tolerated in the ? elds is 80 and 50 m3 haA1 for OMW obtained by centrifuge and pressure extraction techniques, respectively (Law N1 574, 1996). The addition of such compounds may cause signi? cant shifts in the structure and the function of the microbial community, which in turn may in? uence the viability of the soil for agriculture. The effect of the OMW on the physical and chemical characteristics of the soil are well documented (Cabrera et al. , 1996; Cox et al. 1997; Sierra et al. , 2001; Zenjari and Nejmeddine, 2001; Rinaldi et al. , 2003). However, these studies did not deal with the effect of this waste on the microbial community of the soil (Moreno et al. , 1987; Paredes et al. , 1987; Kotsou et al. , 2004). An integrated approach using a pre-treatment of the OMW with the white-rot fungus Phanerochaete chrysosporium followed by an anaerobic digestion was developed in our laboratory in order to reuse the ef? uent in agriculture (Sayadi and Ellouz, 1995). Thus, the aim of our work was to investigate A. Mekki et al. he effect of untreated and biologically treated OMW on the soil characteristics and on the microbial communities. Materials and methods OMW origin The fresh OMW was taken from a three-phase discontinuous extraction factory located in Sfax, Tunisia. Biological treatment of OMW The treated OMW was obtained with an integrated process based on aerobic fungal pre-treatment using P. chrysosporium DSMZ 6909 followed by a decantation step then anaerobic digestion (Sayadi and Ellouz, 1995). The characteristics of the treated and untreated OMW are given in Table 1. Table 1.Chemical and physical properties of untreated and biological treated OMW Parameter pH (25 1C) Electric conductivity (25 1C) (dS mA1) Salinity (g lA1) Colour (absorbance 395 nm) UV absorbance 280 nm BOD5 (g lA1) COD (g lA1) Glucose (g lA1) Residual solids (g lA1) Total solids (%) Total volatiles (%) Total suspended solids (g lA1) Volatiles suspended solids (g lA1) Nitrogen (g lA1) Phosphorous (g lA1) Potassium (g lA1) o-di-phenols (g lA1) Total poly phenols (g lA1) Residual oils (g lA1) Toxicity by LUMIStox (% inhibition) Untreated OMW 5. 46 8. 7 5. 9 82 368 34. 117 12 26 11. 4 9. 3 8. 9 6. 5 1. 58 0. 84 5. 2 8. 395 9. 200 9. 2 100 Treated OMW 7. 6 11. 3 9. 7 44 38 4. 5 21. 9 ND ND 2. 5 1. 42 3. 5 2. 7 1. 72 1. 12 4. 4 1. 265 1. 578 Not detected 38 ARTICLE IN PRESS Changes in microbial and soil properties following amendment 95 Study sites and sampling The study area consisted in a ? eld of olive trees located in Chaal at 60 Km to the South-West of ? Sfax, Tunisia, North latitude 341 30 , East longitude 101 200 . The mean annual rainfall is 200 mm (Ben Rouina et al. , 2001). The ? eld was divided in ? ve plots.Three experimental plots P1, P2, and P3 we re annually amended in February with 50, 100, and 200 m3 haA1 of untreated OMW respectively (Ben Rouina, 1994). The plot P4, was annually amended with 400 m3 haA1 of the treated OMW. The ? fth plot, plot C, was not amended and served as control. Soil samples were collected from different parts of each plot from 0 to 10 cm deep, using a soil auger. All soil samples, taken from each plot were then mixed, air-dried, sieved with a mesh size of 450 mm and stored at 4 1C prior to use. Water content was immediately determined before airdrying the sample. xtracted with 1 M solution of ammonium acetate (pH 7) using a soil/solution ratio of 1/10 (w/ v). The suspension was analysed with an inductively coupled plasma atomic emission spectrometer (ICP-AES, ARL 3580). Microtoxicity determination The microtoxicity test consisted in the inhibition of the bioluminescence of Vibrio ? scheri LCK480 using the LUMIStox system (Dr. Lange GmbH, Duesseldorf, Germany) and according to ISO 11348-2 (1998). Pe rcentage inhibition of the bioluminescence was achieved by mixing 0. 5 ml of OMW and 0. 5 ml luminescent bacterial suspension.After 15 min exposure at 15 1C, the decrease in light emission was measured. The toxicity of the OMW was expressed as the percent of the inhibition of bioluminescence (%IB) relative to a non-contaminated reference. A positive control (7. 5% NaCl) was included for each test. Physicochemical analyses Analysis of ortho-diphenols: The ortho-diphenols concentration in the OMW was quanti? ed by means of Folin-Ciocalteau colorimetric method (Box, 1983) using caffeic acid as standard. The absorbance was determined at l ? 765 nm. Analysis of total polyphenols: OMW was centrifuged at 7000 rpm for 20 min.The supernatant was extracted three times with ethyl acetate. The collected organic fraction was dried and evaporated under vacuum. The residue was extracted two times with dichloromethane in order to remove the non-phenolic fraction (lipids, aliphatic, sugars). The liq uid phase was discarded while the washed residue was weighed and analysed by gas chromatography coupled with the mass spectroscopy technique to con? rm the phenolic structure of the extracted compounds. COD was determined according to Knechtel (1978) standard method. BOD5 was determined by the manometric method with a respirometer (BSB-Controller Model 620 T (WTW)).Dry weight and moisture content were determined by weighing samples before and after drying overnight at 105 1C. Organic matter was determined after furnacing samples at 550 1C for 4 h. Total carbon and nitrogen were determined by dry combustion (TOC Analyser multi-N/C 1000). Ca, K, Na, and Mg analyses, the air-dried soil was Respirometric test Biological activity in the soil was achieved by measuring CO2 evolution in the aerobic condition ? (Ohlinger, 1995). The soil sample was humidi? ed to 50% of its water holding capacity and incubated at 30 1C in the dark. The CO2 evolved was trapped in an NaOH solution and titrated with HCl.Microbial estimation Ten grams of the soil sample was suspended in an erlenmeyer ? ask containing 90 ml of a sterile solution (0. 2% of sodium polyphosphate (NaPO3)n in distilled water, pH 7. 0) and 10 g of sterile glass beads (1. 5 mm diameter). The ? ask was shaken at 200 rpm for 2 h. Serial 10-fold dilutions of the samples in a 0. 85% NaCl solution were plated in triplicate on PCA at 30 1C for total bacterial counts, on Sabouraud containing chloramphenicol at 25 1C for yeasts and moulds, on DCL at 37 1C for total coliforms, and on soil extract agar at 30 1C for actinomycetes.Soil extract agar was prepared as follows: 1 kg of soil was added to 1 l of distilled water and agitated energetically. Supernatant was ? ltered. Its pH was adjusted to 7 and sterilized at 121 1C for 20 min twice. A 200 ml of this extract and 20 g of Agar-agar were added to 800 ml of distilled water and sterilized at 121 1C for 20 min. Penicillin G, Cycloheximide, Ampicillin and Nistatin were dissolv ed in water and sterilized by ? ltration (0. 22 mm) and ARTICLE IN PRESS 96 were added at ? nal concentration of 1, 50, 10 and 50 mg lA1, respectively.For spore-forming bacteria counts, aliquots were heated for 10 min at 80 1C before spreading on PCA and incubation at 37 1C. Ammonia and nitrite-oxidizing bacteria were enumerated by the most probable number (MPN) procedure (Trolldenier, 1995). Culture tubes supplemented either with ammonium or nitrite were inoculated with serially diluted soil suspension. After an extended incubation of 4 weeks at 28 1C, acidi? cation of the medium was recorded by taking colour change as an indication for growth of ammonium oxidizers and the absence of nitrite as an indication for growth of nitrite oxidizers.Subsequently, the MPN was calculated in accordance with the table of MPN values. The total nitri? ers count was the sum of the oxidizers of ammonium and of nitrite. Each soil sample was analysed in duplicate and the dilution series were plated in triplicate for each medium. All these counts were expressed as colony forming units (CFU) per gram of dried soil (24 h at 105 1C). The total nitri? ers count was expressed as MPN per gram of dried soil. A. Mekki et al. high content of phenolics (9. 2 g lA1). This toxicity was reduced to 38%IB in treated OMW which contained only 1. 8 g lA1 of phenolics. The COD (21. 9 g lA1) of treated OMW remained high and far exceeded the standard for direct discharge to a natural water body. Several costly steps are necessary if we want to reach the Tunisian standard (0. 09 g lA1). The treated OMW contained appreciable concentrations of N, P, and K. This ef? uent was free of pathogens, relatively not toxic and contained low concentrations of heavy metals. Apart from COD, BOD5 and black colour, the quality of treated OMW was high and could be used for irrigation after ? eld tests.Analytical results of soils pro? les A darker soil colour was observed in the plots amended with OMW. After drying, the amended soils showed higher compactness and hardness. Soils were sampled and analysed in a particularly dry year in Tunisia. Only weak precipitations were recorded in February, May and November. The soil water content was very weak and it varied between 0. 8% and 1. 15% in the samples collected in September (Table 2). The pH increased to 9. 2 when P4 soil was amended with treated OMW and slightly decreased to 7. 4 when P3 soil was amended with raw OMW.Table 2 shows also that salinity of the amended soil increased proportionally with quantity of treated or untreated OMW. The content of the nutrients as total carbon (Ctot), total nitrogen (Ntot), P, K, Mg and humus increased after spreading Results Characterisation of the ef? uents Untreated OMW totally inhibited V. ?scheri (Table 1). This toxicity was essentially due to its Table 2. Results of the air-dried soils characterization C 89. 82 7. 44 2. 74 1. 14 7. 9 69 0. 02 0. 001 0. 14 0. 25 0. 02 14. 70 0. 23 0. 0312 2. 001 4 8. 7 P1 ND ND ND Characteristics 9 8 Particle size > > Sand = < distribution ? ? clay > > ; : in control soil Silt Moisture content (%) pH (KCl) Salinity (mg kgA1) P (mg gA1) P (water soluble) (mg gA1) K (mg gA1) Mg (mg gA1) Na (mg gA1) Ca (mg gA1) Ntot (mg gA1) N-NH4 (mg gA1) Ctot (mg gA1) Humus (mg gA1) C/N P2 ND ND ND 1. 15 7. 6 336. 5 0. 08 0. 016 1. 60 0. 40 0. 03 16. 20 0. 95 0. 055 15. 504 31 16. 32 P3 ND ND ND 1. 07 7. 4 447. 5 0. 08 0. 12 1. 80 0. 37 0. 04 15. 80 0. 91 0. 089 16. 999 34 18. 68 P4 ND ND ND 0. 82 9. 2 473 0. 05 0. 027 2. 42 0. 33 0. 31 14. 70 0. 45 0. 088 4. 001 8 8. 89 1. 13 7. 9 240 0. 03 0. 003 1. 05 0. 35 0. 17 19. 80 0. 56 0. 044 8. 002 16 14. 29P1, P2, and P3: Soils amended with 50, 100, and 200 m3 haA1 of untreated OMW respectively; P4: Soil amended with 400 m3 haA1 of the treated OMW. The plot C was not amended and served as control. ND: not done. ARTICLE IN PRESS Changes in microbial and soil properties following amendment the treated or untreated OMW. The C /N ratio remained constant in the soil amended with treated OMW while it increased proportionally in the soils amended with untreated OMW. Phenolic compounds migrated in soil according to their molecular mass. Polyphenols were adsorbed in the soil upper layers while monomers migrated in depth.Indeed phenolic monomers were detected at 1. 2 m depth 1 year after irrigation with untreated OMW (data not shown). C-CO2 18 16 C-CO2 and Ctot (mg g-1) 14 12 10 8 6 4 2 Ctot C-CO2/Ctot 1. 8 1. 6 1. 4 C-CO2/Ctot 1. 2 1 0. 8 0. 6 0. 4 0. 2 0 C P1 P2 Soil P3 P4 97 Soil respiration A respirometric test was achieved on soils sampled in September. CO2 production increased with OMW amendment (Fig. 1). For the treated OMW, a more pronounced CO2 production rate was shown since the ? rst week of incubation. However, for the untreated OMW, the start-up of the CO2 production was delayed to the 3rd week of respiration.The speci? c respiration rate expressed as the ratio of C-CO2/Ctot for the different soil samples is shown in Fig. 2. The amendment of the soil with 200 m3 haA1 increased the carbon content to 17 mg gA1 while the speci? c respiration remained very low. However, the amendment with 400 m3 haA1 of treated OMW did not much affect the speci? c respiration of the soil. 0 Figure 2. Speci? c respiration C-CO2/Ctot, cumulative CCO2, and total carbon Ctot of the soil samples studied. shown). An increase in the total micro? ora count was observed in P1, P2 and P4 in all dates of sampling (Table 3).However, at 200 m3 haA1 of untreated OMW, the total bacterial counts remained much higher compared to the control soil, but lower compared to the other doses of OMW. Effect on soil microbiology Viable mesophilic micro? ora Generally, the total micro? ora increased with the soil humidity. OMW enhanced the water holding capacity of the soil. The soil water content increased when the OMW dose increased (data not 12 Viable yeasts and moulds micro? ora In comparison with the control soil, an o verall high CFU of fungi in the soil amended with untreated OMW was found (Table 4).In all dates of sampling, the fungal CFU number decreased when OMW increased but remained much higher than the control soil except for biologically treated OMW which had a lower CFU than the control. We noted that the pH of OMW leaving the anaerobic reactor ranged between 7. 6 and 8. This pH increased to 8. 7 during its storage at ambient temperature. After amendment with treated OMW, the pH of the soil increased to 9. 2. Such pH value is considered as detrimental for the fungal growth. C P1 P2 P3 P4 mg C-CO 2 g -1 (dry soil) 10 8 6 4 2 0 0 5 10 15 20 25 30 Viable total nitri? rs Soils C, P1 and P2 showed broadly comparable nitri? er MPN numbers. However, a decrease in viable nitri? ers count was observed in P3. This decrease was more signi? cant in P4 (Table 5). Time (d) Figure 1. Cumulative respiratory activity as mg CO2 gA1 dry soil of different samples incubated over 28 days at 28 1C in the dark. Viable actinomycetes The actinomycetes CFU number increased when OMW doses increased up to the dose of 100 m3 haA1. At 200 m3 haA1 of untreated OMW, the CFU number remained higher than C and P1 (50 m3 haA1). However, it was lower than P2 (100 m3 haA1) (Table 6).ARTICLE IN PRESS 98 Table 3. Aerobic heterotrophic bacteria counts CFU ( A 104) gA1 in the different plots Feb C P1 P2 P3 P4 3472 8574. 95 12177. 11 6673. 9 9075. 3 May 6974. 05 7774. 52 8975. 32 7274. 23 10175. 93 Jun 24. 571. 44 45. 572. 67 57. 573. 38 5773. 35 7974. 64 Sep 1570. 88 48. 572. 85 65. 573. 85 43. 572. 55 6073. 52 Nov 21. 571. 26 8374. 88 16179. 46 9275. 4 15879. 29 A. Mekki et al. Data expressed as mean value (three replicates) and standard deviation for colony forming units per gram of dried soil. Table 4. Fungi counts in the different plots CFU ( A 104) gA1 Feb May 370. 5 11. 573. 64 571. 58 4. 671. 45 1. 8570. 58 Jun 370. 95 1775. 38 1574. 75 1173. 48 2. 8570. 9 Sep 1. 370. 41 15. 574. 9 1073. 17 4. 171. 2 9 1. 7470. 55 Nov 2. 770. 85 14. 774. 65 13. 574. 27 11. 273. 55 1. 3570. 42 C P1 P2 P3 P4 3. 571. 11 1073. 17 5. 571. 74 7. 572. 37 1. 8270. 57 Table 5. Nitri? ers counts MPN (x104) gA1 in the different plots Feb May 4. 770. 62 4. 570. 59 4. 270. 55 2. 870. 37 0. 4870. 063 Jun 3. 270. 42 3. 470. 45 2. 670. 34 1. 770. 22 0. 5170. 07 Sep 2. 870. 37 2. 470. 31 2. 470. 31 1. 170. 14 0. 0770. 009 Nov 3. 870. 5 3. 170. 41 2. 870. 37 1. 170. 14 0. 70. 11 C P1 P2 P3 P4 3. 670. 47 2. 670. 34 270. 26 1. 970. 25 0. 4670. 06 Table 6. Actinomycetes counts CFU ( A 104) gA1 in the different plots Feb May 2. 170. 28 14. 571. 93 18. 572. 46 1872. 39 17. 572. 33 Jun 270. 26 871. 06 15. 572. 06 1271. 59 15. 672. 07 Sep 270. 26 1071. 33 10. 571. 39 5. 570. 73 12. 2971. 63 Nov 3. 570. 46 12. 871. 7 17. 272. 29 14. 771. 95 15. 772. 09 C P1 P2 P3 P4 0. 670. 08 770. 93 1171. 46 570. 66 13. 2971. 77 Viable spore-forming bacteria and total coliforms The spore-forming bacteria increased with the increase of OMW doses (data not shown).For P4 soil, it shifted from the CFU gA1 number ranging from 0. 28 to 1. 12 A 104 in the control soil to CFU gA1 number ranging from 1. 1 to 2. 12 A 104 in P4 amended with 400 m3 haA1 of treated OMW. Total coliforms are well known as contaminant indicator bacteria in wastewater and soil. The number of the total coliforms was very low in the control soil. It increased when the treated or untreated OMW quantity increased (data not shown). Discussion This study attempted to demonstrate that soil amended with different concentrations of OMW showed modi? ation of its structure and its texture. The acidity of the untreated OMW was compensated by the soil carbonate alkalinity. The carbonates at the same time became bicarbonates, moved and accumulated in deeper horizons as was shown by Sierra et al. (2001). The increase of the salinity in the soil could result from the main ionic species, sodium chloride and sulphate, coming from the treated or untreated OMW. This is in line with previous ? nding ARTICLE IN PRESS Changes in microbial and soil properties following amendment (Paredes et al. , 1987; Sierra et al. 2001). Hence, in long-term applications, replacement of the soil calcium by the cations of Na, K and Mg could lead to the degradation of the soil structure and the formation of saline soils as was suggested earlier by Zenjari and Nejmeddine (2001). Biologically treated OMW had a pH48, and the alkalinity of this waste was not regulated (buffered) by the soil components. Soil porosity was reduced by the combined effect of the suspended solids and the COD formed by highly polymerised polyphenolic compounds such as humic acid-like substances (Cox et al. 1997). Consequently, soil plugged and became impermeable which led to a reduction of the soil aerobic community such as fungi and actinomycetes. This ? nding con? rms the reported correlation between the soil pH and the ( change in community composition (Frostegard et al. , 1993; Perkiomaki and Fritze, 2002). ? ? The increase of nutrient contents, Ctot, Ntot, P Mg , and K at all OMW treated plots, may have a bene? cial effect on the soil fertility. The OMW treated soil exhibited a higher respiration rate compared to the control soil.Nevertheless, when taking into account the added organic carbon, this activity was not in proportional ratio. Speci? c respiration expressed as C-CO2/Ctot decreased from 1. 7 in the control soil to 0. 5 in the soil amended with 100 m3 haA1 of untreated OMW. Yet, it slightly decreased to 1. 15 in the soil amended with 400 m3 haA1 of treated OMW. This can be explained by the fact that the phenolic compounds may inhibit the soil respiration, especially in the high OMW doses, and thus neutralize the favourable in? uence of its higher nutrient contents as was demonstrated by Sierra et al. 2001), Cox et al. (1997), Cabrera et al. (1996), and Paredes et al. (1987). In simple terms, the inhibition of soil respiration could be caused by the fact th at the big amount of carbon added to the soil was unavailable to the micro? ora under the effect of its strong adsorption or its reaction with the components of the soil. This disproportion could not be due to the added salt because despite the high content of salt in P4 (473 mg kgA1) compared to that in P3 (447. 5 mg kgA1), the former had a nearer speci? c respiration rate to the control plot C which contained only (69 mg kgA1).Addition of the untreated or the biologically treated OMW to the soil created some modi? cations in the average values for total number of microorganisms and their repartition. Results showed an initial increase in the numbers of CFU in most micro? ora groups after the OMW amendment, excepted for nitri? ers which decreased. In line with this ? nding, Paredes et al. (1987) reported also an increase in the total viable counts in the soil polluted with OMW. The overall low CFU number 99 observed in the P3 soil could be explained by the OMW dose becoming high an d toxic (Capasso et al. 1995). The chemolithotrophic ammonia-oxidizing bacteria (AOB) are responsible for the ? rst ratelimiting step in nitri? cation in which ammonia (NH3) is transformed to nitrate (NOA) via nitrite 3 (NOA). The AOB play a critical role in the natural 2 nitrogen cycle (Oved et al. , 2001; Mendum and Hirsch, 2002). This micro? ora could be affected by a variety of chemical conditions including aromatic compounds and salts. Indeed, the number of nitri? ers shifted from the CFU gA1 number ranging from 2. 8 to 4. 7 A 104 in the control soil to CFU gA1 number ranging from 0. 46 to 0. A 104 in P4 amended with 400 m3 haA1 of treated OMW. Some authors reported that higher pH is not favourable for some phylogenetic groups of nitrifying bacteria (Kowalchuk et al. , 2000). Moreover, some residual polyphenolic compounds present in treated OMW may be toxic for this sensitive category of microorganisms (Peredes et al. , 1987). Actinomycetes and spore-forming bacteria play a sig ni? cant role in the organic matter cycle in nature, by virtue of their considerable powers and ability to break down complex organic molecules. Actinomycetes counts were strongly enhanced by treated and untreated OMW amendment.The introduction of organic pollutants, which can potentially act as toxic substances and nutrient sources, was shown to preferentially stimulate speci? c populations (Atlas et al. , 1991). The increase of the CFU count of spore-forming bacteria were in accordance with the earlier investigations of Paredes et al. (1987) who reported an increase in spore-forming bacteria counts but a decrease in the proportion of this population in the community from 10% to 12% in the control soil to 0. 02% in the polluted soil with OMW. Fungi populations are known by their considerable depolymerising enzymes and their resistance to recalcitrant substances.The OMW enhanced fungi, the most important organisms decomposing lignin and polyphenols (Scheu and Parkinson, 1994; Borken et al. , 2002). Consequently, this population was favoured in plots P1, P2 and P3 where pH and C/N ratio were also more favourable compared to the control. This observation con? rms previous ? ndings by Perkiomaki and Fritze (2002) and Joergensen et al. (1995). ? Conclusion Based on previous studies and our results, we suggest that the effect of the long-term use of OMW in the ferti-irrigation on the soil microbial commu- ARTICLE IN PRESS 00 nity, the soil fertility and the soil physico-chemical properties remain unclear. Yet, speci? c attention must be devoted to the irrigation potential of treated OMW with explicit reference to the major crops of agricultural interest. The following guidelines should be adhered to the OMW spreading on soil A. Mekki et al. Box, J. D. , 1983. Investigation of the Folin-Ciocalteau phenol reagent for the determination of polyphenolic substances in natural waters. Water Res. 17, 511–522. Cabrera, F. , Lopez, R. , Martinez-Bordiu, A. , Dupuy de Lome, E. , Murillo, J. M. , 1996.Land treatment of olive oil mill wastewater. Int. Biodeterior. Biodegrad. 38 (3-4), 215–225. Capasso, R. , Evidenti, A. , Schivo, L. , Orru, G. , Marcialis, M. A. , Cristinzio, G. , 1995. Antibacterial polyphenols from olive oil mill waste waters. J. Appl. Bacteriol. 79, 393–398. Casa, R. , D’Annibale, A. , Pieruccetti, F. , Stazi, S. R. , Giovannozzi Sermanni, G. G. , Lo Cascio, B. , 2003. Reduction of the phenolic components in olive-mill wastewater by enzymatic treatment and its impact on durum wheat (Triticum durum Desf. ) germinability. Chemosphere 50, 959–966. Cereti, C. F. , Rossini, F. Federici, F. , Quaratino, D. , Vassilev, N. , Fenice, M. , 2004. Reuse of microbially treated olive mill wastewater as fertiliser for wheat (Triticum durum Desf. ). Bioresource Technol. 91, 135–140. Cox, L. , Celis, R. , Hermosin, M. C. , Beker, A. , Cornejo, J. , 1997. Porosity and herbicide leaching in soils amended with oli ve-mill wastewater. Agri. Ecosyst. Environ. 65 (2), 151–161. D’Annibale, A. , Casa, R. , Pieruccetti, F. , Ricci, M. , Marabottini, R. , 2004. Lentinula edodes removes phenols from olive-mill wastewater: impact on durum wheat (Triticum durum Desf. ) germinability.Chemosphere 54, 887–894. Ehaliotis, C. , Papadopoulou, K. , Kotsou, M. , Mari, I. , Balis, C. , 1999. Adaptation and population dynamics of Azotobacter vinelandii during aerobic biological treatment of olive-mill wastewater. FEMS Microbiol. Ecol. 30, 301–311. Feria, A. L. , 2000. The generated situation by the O. M. W. in Andalusia. Actas/Proceedings-Workshop Improlive2000-Annex A1. ( ( (( Frostegard, A. , Baath, E. , Tunlid, A. , 1993. Shifts in the structure of soil microbial communities in limed forests as revealed by phospholipid fatty acid analysis. Soil Biol. Biochem. 25, 723–730. ISO 11348-2, 1998.Water quality – Determination of the inhibitory effect of water samples on the light emission of Vibrio ? scheri (Luminescent bacteria test) – Part 2: Method using liquid-dried bacteria Joergensen, R. G. , Anderson, T. H. , Wolters, V. , 1995. Carbon and nitrogen relationship in the microbial biomass of soils in beech Fagus sylvatica L. forest. Biol. Fert. Soils 19, 141–147. Kissi, M. , Mountadar, M. , Assobhei, O. , Gargiulo, E. , 2001. Roles of two white-rot basidiomycete fungi in decolorisation and detoxi? cation of olive mill waste water. Appl. Microbiol. Biotechnol. 57, 221–226. Knechtel, R. J. 1978. A more economical method for the determination of chemical oxygen demand. Water Pollut. Control (May/June), 25–29. Kotsou, M. , Mari, I. , Lasaridi, K. , Chatzipavlidis, I. , Balis, C. , Kyriacou, A. , 2004. The effect of olive oil mill    do not exceed 50 m3 haA1 yA1 of untreated OMW and to decrease the dose of treated OMW up to 100 m3 haA1 yA1 to avoid the increase of the soil salinity. integrate a polishing tertiary treatment of OMW for reducing the residual coloration and toxicity of the ef? uent. frequently till and avoid dry soil conditions to maintain a maximal activity of the soil micro? ra. Acknowledgments This work was supported by Inco-med project ‘‘Mediterranean usage of biotechnological treated ef? uent water’’ ICA3-CT-1999-00010. The authors would like to thank: ‘‘Institut de l’Olivier de Sfax’’ and Dr Bechir Ben Rouina for their permission to use the experimental plant of OMW amendment at Chaal farm. ? References Ammar, E. , Ben Rouina, B. , 1999. Potential horticultural utilization of olive oil processing waste water. Acta Horticult. 474 (2), 741–744. Angelakis, A. N. , Marecos Do Monte, M. H. F. , Bontoux, L. , Asano, T. , 1999.The status of wastewater reuse practice in the Mediterranean basin: need for guidelines. Water Res. 33 (10), 2201–2217. Atlas, R. M. , Horowitz, A. , Krichevsky, M. , Bej, A. K. , 1991. Respons e of microbial populations to environmental disturbances. Microb. Ecol. 22, 249–256. Ben Rouina, B. , 1994. Repercussions agronomiques de ? l’epandage des margines comme fertilisant. Interna? tional conference on Land and Water Resources Management in the Mediterranean Region II, 583–594. Ben Rouina, B. , Taamallah, H. , Ammar, E. , 1999. Vegetation water used as a fertilizer on young olive plants. Acta Horticult. 74 (1), 353–355. Ben Rouina, B. , Gargouri, K. , Taamallah, H. , 2001. L’utilisation des margines comme fertilisant en agriculture. Journees Mediterraneennes de l’oliviers. ? ? ? Nimes, France 6–7 & 8 Avril. Borken, W. , Muhs, A. , Beese, F. , 2002. Changes in microbial and soil properties following compost treatment of degraded temperate forest soils. Soil Biol. Biochem. 34, 403–412. ARTICLE IN PRESS Changes in microbial and soil properties following amendment wastewater (OMW) on soil microbial communities and suppre ssiveness against Rhizoctonia solani. Appl. Soil Ecol. 26, 113–121. Kowalchuk, G. A. Stienstra, A. W. , Heilig, G. H. , Stephen, J. R. , Woldendorp, J. W. , 2000. Molecular analysis of ammonia-oxidizing bacteria in soil of successional grasslands of the Drentsche A (The Netherlands). FEMS Microbiol. Ecol. 31, 207–215. Law N1 574, 1996 (Legge 574, 11/11/1996). Norme sull’utilizzazione agronomica dei re? ui oleari. Gazzetta Uf? ciale N. 265 del 12 novembre, 1996. Lesage-Meessen, L. , Navarro, D. , Maunier, S. , Sigoillot, JC. , Lorquin, J. , Delattre, M. , Simon, J. -L. , Asther, M. , Labat, M. , 2001. Simple phenolic content in olive oil residues as a function of extraction systems.Food Chem. 75 (4), 501–507. Marques, I. P. , 2001. Anaerobic digestion treatment of olive mill wastewater for ef? uent re-use in irrigation. Desalination 137, 233–239. Mendum, T. A. , Hirsch, P. R. , 2002. Changes in the population structure of b-group autotrophic ammonia oxidizing bacteria in arable soils in response to agricultural practice. Soil Biol. Biochem. 34, 1479–1485. Moreno, E. , Perez, J. , Ramos-Cormenzana, A. , Martinez, J. , 1987. Antimicrobial effect of waste water from olive oil extraction plants selecting soil bacteria after incubation with diluted waste.Microbios 51, 169–174. Mulinacci, N. , Romani, A. , Galardi, C. , Pinelli, P. , Giaccherini, C. , Vincieri, F. F. , 2001. Polyphenolic content in olive oil waste waters and related olive samples. J. Agri. Food Chem. 49, 358–3514. ? Ohlinger, R. , 1995. Soil respiration by titration. In: ? Schinner, F. , Ohlinger, R. , Kandeler, E. , Margesin, R. (Eds. ), Methods in Soil Biology. Springer, Berlin, pp. 95–98. Oved, T. , Shaviv, A. , Goldrath, T. , Mandelbaun, R. T. , Minz, D. , 2001. In? uence of ef? uent irrigation on community composition and function of ammoniaoxidizing bacteria in soil.Appl. Environ. Microbiol. 67, 3426–3433. Paredes, M. J. , Mo reno, E. , Ramos-Cormenzana, A. , Martinez, J. , 1987. Characteristics of soil after 101 pollution with waste waters from oil extraction plants. Chemosphere 16, 1557–1564. Paredes, C. , Roig, A. , Bernal, M. P. , Sanchez-Monedero, M. A. , Cegarra, J. , 2000. Evolution of organic matter and nitrogen during co-composting of olive mill wastewater with solid organic wastes. Biol. Fert. Soils 32 (3), 222–227. Perkiomaki, J. , Fritze, H. , 2002. Short and long-term ? ? effects of wood ash on boreal forest humus microbial community.Soil Biol. Biochem. 34, 1343–1353. Rinaldi, M. , Rana, G. , Introna, M. , 2003. Olive-mill wastewater spreading in southern Italy: effects on a durum wheat crop. Field Crops Res. 84, 319–326. Sayadi, S. , Ellouz, R. , 1992. Decolourization of olive mill waste-waters by the white-rot fungus Phanerochaete chrysosporium : involvement of the lignin-degrading system. Appl. Microbiol. Biotechnol. 37, 813–817. Sayadi, S. , Ellouz, R. , 1995. Roles of lignin peroxidase and manganese peroxidase from Phanerochaete chrysosporium in the decolorization of olive mill wastewaters.Appl. Environ. Microbiol. 61, 1098–1103. Sayadi, S. , Allouche, N. , Jaoua, M. , Aloui, F. , 2000. Detrimental effects of high molecular-mass polyphenols on olive mill wastewater biotreatment. Process Biochem. 35, 725–735. Scheu, S. , Parkinson, D. , 1994. Changes in the bacterial and fungal biomass C, bacterial and fungal biovolume and ergosterol contents after drying, remoistening and incubation of different layers of cool temperature forest soils. Soil Biol. Biochem. 26, 1515–1525. Sierra, J. , Marti, E. , Montserrat, G. , Cruanas, R. , Garau, M. A. , 2001.Characterization and evolution of a soil affected by olive oil mill wastewater disposal. Sci. Total Environ. 279, 207–214. Trolldenier, G. , 1995. Nitri? ers by MPN method. In: ? Schinner, F. , Ohlinger, R. , Kandeler, E. , Margesin, R. (Eds. ), Methods in Soil Biology. Springer, Berlin, pp. 32–36. ? ? Yesilada, E. , Ozmen, M. , Yeslada, O. , 1999. Studies on the toxic and genotoxic effect of olive oil mill wastewater. Fresenius Envir. Bull. 8, 732–739. Zenjari, A. , Nejmeddine, A. , 2001. Impact of spreading olive mill wastewater on soil characteristics: laboratory experiments. Agronomie 21, 749–755. My Aim in Life There are two things to aim at in life: first, to get what you want, and after that to enjoy it. Only the wisest of mankind achieve the second. Logan P. Smith People have set their own aim depending upon their abilities. Some people are doctors, engineers, Charter Accountants, pilots, teachers and many more. Our life is too short so we have to strive to attain our aim with all our hard work. The main objective for achieving the aim is to get material pleasures, mental happiness as well as satisfaction. Once a person chives his aim he can live a prosperous life.The mere act of aiming at something big, makes you big. Charcoal Nehru My aim in life is neither to collect money nor for fame. It is my desire to become a well-qualified doctor. I do not just wish to be an ordinary doctor. The world remembers with thankfulness the name of the man who gave to the world vaccination. The world will remember forever the man who gave us penicillin. As a doctor I want to serve the humanity. Don't ai m for success if you want it; just do what you love and believe in, and it will come naturally.David Frost have an ambition to do something in this world so, great as the doctors and the courageous founders did in the past. I would like to give the world some new drugs and injections that will cure some of the diseases that people are still suffering from. An aim in life is the only fortune worth finding. Robert Louis Stevenson know, my profession is very dignified and it will help me to get peace and satisfaction in life. It provides us best chances of service. Sympathy to human being is the sympathy to one own self. Quotations About this essay. Future favors the bold.An early death is better than an aimless life. A noble aim is simply a noble deed. My goal in life is to survive. Everything else is just a bonus. The greater danger for most of us lies not in setting our aim too high and falling short; but in setting our aim too low, and achieving our mark. Michelangelo The aim of ar t is to represent not the outward appearance of things, but their inward significance. Aristotle. Aim above morality. Be not simply good, be good for something.