Year:2006 | Volume:11 | Issue:4|Papers Count:25

In the last two decades there has been an increasing interest in the concept of agricultural sustainability. Philosophical, theoretical and practical aspects, primarily the environmental concern, have been extensively developed in agronomic and economic forums. The important concern now is how to use sustainability as an operational criterion in the management of agricultural systems. This paper presents a new modeling framework which uses quantified sustainability criteria in an optimization model. Fractional programming is presented as a tool for studying the sustainability of agricultural systems. The essentials of the technique in both the single and the multi-objective cases are outlined.

The overall goal of this paper is estimate technical, allocative, economic and scale efficiencies of a sample of 180 cooperative members and non-cooperative farms in Qomrood in Qom province, using parametric and non-parametric approaches. To examine which factors play an important role in determining farm technical efficiency, developed and employed a model that allows for assessing relative technical efficiencies of sample farms and identifies inefficiency sources that are ranked by their influences on efficiencies. The efficiency findings for cooperative and non-cooperative members indicated that on average, members of the cooperatives gain higher levels of technical efficiency scores than non-cooperative members.

In present investigation, vegetative compatibility groups (VCGs) of 24 isolates of Fusarium oxysporum collected from 8 regions (Oraki, Baho Kelat, Dashtyari, Rask, Shirgovaz, Kahir, Goodan, and Chabahar) were determined using nitrate non-utilizing (nit) mutants. In total, 230 nit mutants were synthesized from 24 isolates and their phenotypic classes on medium sodium nitrate, sodium nitrite, hypoxanthin, ammonium tartarate and urin asid were investigated. Of these, 68% belonged to nit 1, 18% to nit 3, and 14% to Nit M. To determine VCGs and complementation tests, pairings were made between all Nit M and nit 1 and/or nit 3. In a compatible reaction between Nit M and two other nit mutants, a dense growth at the line of contact between two colonies was formed after 7-14 days. All isolates examined in this study, were grouped into two VCG a of which 15 isolates, belonged to VCG a and 9 isolates to VCG b.

Information flows in a network of actors. This communication network which includes both actors and communication linkages among them was studied as agricultural knowledge and information system framework. This research was an attempt to analyze the communication networks among actors involved in range knowledge and information system in sustainability of range ecosystem in Fars province using an analytical - descriptive research method. This research is limited to actor activities from 1378 to 1382. Population of study included the stakeholders involved in range knowledge and information system in sustainability of range ecosystem in Fars province, of which a sample size was taken by using multi - cluster and snowball sampling methods. Dependent variable of the study included range knowledge and information network performance and the independent variables were ranger's communication network characteristics. Findings indicates that among the sources of professional information backgrounds, personal experience was the most important information source and Radio, television, educational classes and extension sessions were the most important communication channels for delivery of professional information in range and livestock backgrounds. According to finding of this research, relationships between rangers include, kinship relationship and with organizational actors include administrative relationships. Linkages between rangers included advisory and supportive linkages and between organizational actors included service and advisory linkages and between organizational actors included advisory and extension education and included interorganizational relations. According to the finding of this research, if rangers with economic, extension education and service linkages have a further communication with other rangers and also if rangers with advisory, supportive and extension education linkages have a further communication with organizational actors, they have better knowledge than other rangers.

Type of Spacise is an important factor in adaptiveness of afforestation sketches. For this propose the appropriate sites and quantitative and qualitative condition of afforestation in Khojin forest park and Hiroabad in Khalkhal area have been studied by Transect sampling method. Data processing done with appropriate statistical soft were and results were comparied by t statistical test and duncan test. Results of research show that diameter and height growth of common ash in North. East aspect in khojin park is heigher than Sought. West aspect but due the bad unsuitable climate condition common ash in Suoght. West aspect has better condition. In hiroabade sketch palse acacia has very high growth and spruce and Redcear were destroyed in this zone. Quantitative research of austrian pine which will be found in each of research zones show hight and diameter growth in zone in n.l is higher and bigger than zone n.2 Search results show that Austrian pine & palse acacia & larch are very appropraite in zone n.1 and arizona cypress is appropraite in zone n.2.

This research was carried out to find effect of grazing intensity on soil chemical characteristics. For this purpose, Lar region- in North west of Haraz road, 84km far from Tehran- was selected. By field inspection, three different areas including (Reference area, Key area critical area) were recognized. Then, information of soil was collected as random-systematic method. Soil samples were obtained from two horizons of soil profile (0-10cm, 10-30cm), in three times during grazing season. 20 soil samples were taken from each horizon. Data analysis was carried out using split - split plot design. Firstly, data were tested for normality of distribution. Analysis of variance was used to test the treatment effects. Duncan test was employed to separate the means. Results show that Value of pH, K and P were higher in heavy grazing. Values of these factors were higher in surface layer except for pH. This research showed, heavy grazing jeopardized the sustainability of the ecosystem by creating negative changes in soil characteristics.

Poplar psyllid, Camaratoscena hoberlandti Vondracek, is considered as an important sucking pest of poplar in Iran. Feeding of adults and nymphal instars of the pest induces galls on poplar leaves, In this study that was carried out during 2001, its density on 13 native and exotic black poplar (Populus nigra) clones was evaluated in a randomized complete block design with 3 replications. From 9 stands planted in the middle of each plot, 4 were randomly chosen, then a branch with 130 cm length was selected in each geographical direction and number of galls on it was counted. The statistical data were analyzed by SAS8 software. A significant difference in infection rate was found between clones as well as geographical directions, Mean comparison with Duncken's test showed that Populus nigra 42/51 clone with the highest mean has a high density of the pest, while P.n. 62/149, P.n. 56/72, P.n. 63/135, P.n. 62/191, P.n. 62/127, P.n, 62/154 and P.n. 56/75 clones with no infection can be considered as resistant clones. In the geographical directions, the highest gall density was observed in eastern direction of the trees. Mean number of galls in eastern direction of the trees statistically different from those of western, northern and southern tree directions.

Exact estimation of evapotranspiration as a basic parameter in hydrologic cycle and study, design and management of irrigation systems is of great importance. Excessive data needed in evapotranspiration equations on one hand and lack of access to some of the required data on the other hand has made problems in proper computation of this parameter in some areas. This study aims at evaluating artificial neural networks revenue in reducing required data for estimation of reference evapotranspiration as well as its comparison with experimental methods of FAO-Penman Montith, Blany-Kridel, refined method of Jensen-Haize and Hargrives-Samani. To achieve this objective perceptron multilayer networks with learning law of back propagation error and daily data of Tehran Mehrabad weather station during 1991- 2000 were used. FAO-Penman Montith was selected as the standard method and 11 ANN model with different structures were designed with the parameters (Tmax, Tmin, Tdew, Rn, RHmax, U2, n). Favorite network was selected based on (RMSE, R2, MAE, MBE) criteria. Results showed that ANN 1 model with (Tmean, Rn, U2, RHmean) as input data and ANN10 model with only one input, (Tmean) were the most and least precise models in evaluation of evapotranspiration respectively. Air temperatue and wind velocity were considered to be the two most effective data in models precision. Although reducing the number of input data in ANN models will results in the reduction of their output precision but results showed that ANN models can be used as a useful tool for ET estimation in presence of the methods such as FAO-Penman Montith, Blany-Kridel, refined method of Jensen-Haize and Hargrives-Samani.

Reuse of domestic wastewater and treated effluents for agricultural irrigation will cause the increase of some ions, salts and suspended solids (organic and mineral) to the soil. In this regard, the physical, chemical and biological characteristics of the soil will be affected. One of the most important physical parameters in this case is soil structure and the saturated hydraulic conductivity. Therefore, in order to investigate the effect of irrigation with domestic wastewater on saturated hydraulic conductivity (Ksat), a series of lysimeter studies were carried out. A statistical "factorial experiments in the form of randomized complete design" (3x3x3) was used. Raw and treated domestic wastewater of Ekbatan housing complex and well water (as control) were applied as irrigation water for raw edible vegetables such as parsley, carrot and tomato for a period of two years. Ksat was measured before starting and after the end of experiments by using constant head method. The results showed that Ksat of the soil was increased. The most changes were observed by raw wastewater application and parsley plantation, in amount of 53.2 mm/hr (the initial Ksat before irrigation was 3.1 mm/hr). The statistical analysis showed a significant effect of the 3 source of waters applied and the kind of plants on Ksat at 1% level. By mean test results, the maximum increase of Ksat was occured by raw wastewater application, 11.8 times more than the initial values and followed by treated wastewaters and well water, being 7.6 and 5.2 times, respectively. As plants effect, the maximum increase was occured in lysimeters with parsley plantation, 10.6 times and the minimum was for tomato and about 6 times in compare with the initial measured value of soil saturated hydraulic conductivity (Ksat).

The purpose of this study was to determine planting utilization, introducing a new variety of oil flax fit to region climate, the best planting date to get the high yield and 1000 seeds weight at the north of Varamin. The plan of the experiment was a split plots as a Randomized Complete Block Design (RCBD) with 12 treatments and 4 replications in a two years period and was conducted at the experimental field of the institute of Abureihan, Tehran University. Surveying factors are: 4 planting date 5, 15, 25th Farvardin and 4th Ordibehesht, 3 breeding varieties of oilflax (Atlante, Bionda and Raulinus). Seed yield and weights of 1000 seeds were the quantities. The first results showed that planting date have had significant effect on those quantities at the 1% level, so that planting of Atlante variety at date 5th Farvardin had the most seed yield. The second year results were the same. So that differences for two quantities and interactive effect were significant at the 1% level. Seed yield differ between Raulinus and Bionda at the first planting date were significant at the 5% level, but this differ was non-significant at the next planting dates. 1000 seeds weight of Bionda at first, second and composition analysis had less significant difference than Atlante and Raulinus. The most yield produced by Atlante variety. Generally the treatment composition of first planting (5th Farvardin) and Atlante variety considered as the best planting date and suitable variety for Varamin region.

Selection of drought adapted genotypes and efficient use of water are among the most important goals in the breeding programs. In order to study drought tolerance of three important species of millet, proso millet (Panicum miliaseum), foxtail millet (Setaria italic a) and pearl millet (Pennisetum americanum) were prepared and planted in a split-plot design with two irrigation treatments (well watered and 50% of irrigation requirement) and four replications in Birjand Agricultural Research Station. Deficit irrigation declined yield by reduction of seed number per ear and ear number per plant. This reduction was greater in proso millet than the other two species. In addition, although drought stress caused a reduction in WUE of proso millet, it increased WUE in the other ones. Harvest index also was reduced in the presence of drought stress because of both seed per ear and per plant. On the whole, foxtail millet had the greatest yield in both stress and non-stress conditions.

To determine the effects of water deficiency in different final growth stages of two wheat cultivars (Chamran and Kavir) accompany with application of various elements such as potassium (K), zinc (Zn) and copper (Cu) on yield production, harvest index (HI), concentration of nitrogen (N) and other elements in grain were investigated under weather condition of Sistan. The experiment was carried out as Completely Randomized Block under spilt - spilt plot design with three replicates, on loomy fine sand soil during 2001-2003 growth season at the Research Center Institute of Zabol, Zahak. In this experiment, there were 3 type of irrigation, complete irrigation, halted irrigetion after pollination (10.5-1, Fix scale), and after milky stage of grain (10.5-5, Fix scale) as sub-plots, and fertilizer treatments included; nil fertilizer, copper sulphate (CuSo4), zinc sulphate (ZnSo4) and potassium sulphate (K2So4) 0, 30, 40, 150kg/ha, respectively which is applied at sowing time as sub-sub plot. The results of this study highlight that the respond of grain yieds (GY), biological yield (BY), harvest index (HI), concentration of N, K, Cu and Zn in grain were analyzed. Halted water at 10.5-1, fix scale decreased BY, GY and HI at statistically significant level (p>0.01). But the Chamran produced more BY, GY than Kavir wheat cultivar. In addition, halted water at 10.5-5, Fix scale, increased the concentration of N, K, Zn and Cu in grain. Also application of ZnSo4 and CuSo4 on soil caused increase of Zn and Cu concentration in grain.

In order to determine the suitable planting date and plant population in atumn cultivation of safflower this research was conducted in Jovain - Sabzevar region during 2003-2004. The main plots were planting date, dl (sep 16), d2 (oct 7), d3 (oct 27). Sub plots were SI = 40, S2 = 20, S3 = 13, S4 = 10, S5 = 8 and S6 = 6 plant per m2. With three replications. The result indicated that planting date has significant effect on plant height, number of capitul number of grian per capitul and grian yield. Mean comparision showed that the largest plant height (93 cm), number of capitul (28), number of grian per capitul (33) and grian yield (4.4 ton /ha) were obtained in 3th planting date (d3). So that plant population had significant effect on plant height, distance of first branch from ground, number of secondary branch, number of capitul, number of grain per capitul and grain yield. The result showed that the largest plant height (97 cm), distance of first branch from ground (35 cm) and grain yield (4.5 ton/ha) obtained in 40 and 20 plants per m2. So the largest of secondary branch (13 branchs), number of capitul (29 capitul), number of grain per capitul (33 grain) obtained in 8 and 6 plants per m2. But each factors had no effect on grain weight (1000 grains). Study of phenological stages showed that plant requires. About 2500 Growth Degree Day (GDD) in order to reach physiological maturity. The longest growing stage was rosette stage important. Point in atumn cultivation of safflower in this region was long period of growth (10 month). This factor is unsuitable in sowing of safflower in this region, because it is a limited factor for double Cropping.

An experiment was conducted to determine the effect of dietary treatments on fatty liver-hemorrhagic syndrome (FLHS) in Hy-line W-36 hens. The experiment was conducted in completely randomized design with 6 dietary treatments and 4 replicates pen each with eight hens from 106 to 110 wk of age. One 28-d period used for different dietary treatments including: 1) Control (C); 2) Control with 4%Soy Fatty Acid + Methionine (4%SFA); 3) Control with Linoleic Acid (LA); 4) Control with O.05%Yeast+Balanced Energy (0.05%Y); 5) Control with Methionine + Linoleic Acid + Choline + Balanced Energy (M+LA+CH+BE) and 6) Control with 5%Flaxseed+Choline (5%FS) were compared for treatment of FLHS. Feed intake was significantly (p<0.05) lower for the hens fed %0.05Y and higher for the hens fed LA diets compared to the control. Egg weight was significantly (P<0.05) lower for the hens fed %5FS compared to the control. Shell thickness was significantly (P<0.05) higher for the hens fed 0.05Y compared to the control. Body weight was numerically lower for the hens fed all dietary treatments compared to the control. Liver weight was numerically very lower for the hens fed %0.05Y compared to the control. Liver hemorrhage score (LHS) was positively correlated (p<0.05) with liver weight. The results showed higher body weight, liver weight and hemorrhage score are main predisposing factors for FLHS which were decreased by dietary yeast treatment.

In this research the imported corn and domestic soybean meal, fishmeal also meat and bone meal essential amino acids content and their true digestibility determined by using cecectomized roosters. The digestible lysine in corn, soybean meal, fishmeal, also meat and bone meal were 0/18, 1/9, 3/9 and 1/4 respectively and their digestible methionine were 0/13, 0/5, 1/2 and 0/27 respectively. There are some differences in amino acids digestibility coefficients in any feedstuff. Such differences were low in some amino acids and to some extent high in other amino acids. There were differences in digestibility coefficient of each amino acid too. The differences among amino acids digestibility coefficients in soybean meal were more than other feedstuffs and in fishmeal were the least. The greatest differences were mainly related to lysin. The measured digestible amino acids concentrations were less than the National Reacearch Council (NRC) results. In the case of meat and bone meal, the differences were considerable.

This research down with aim of study of substitution possibility of bagasse neutral Sulfite semi chemical (NSSC) instead of division of wood pulp for production of floating paper in Mazandaran wood and paper complex. In this study use of depithing bagasse in wet process from pars paper factory that located in Khuzestan province. Cooking of pulp is in (NSSC) process with use of chemicals of Mazandran wood and paper factory equal to 20 percent (in dry material basis) in 30 minutes time and 170°c heat. After that bagasse pulp refine with (PFI Mill) refining to 400±25 CSF Freeness and mixture with NSSC pulp of Mazandaran and paper factory. From elective bagasse pulp in 10%, 20% and 30% ratio of pure bagasse, produce of mixtures with NSSC pulp of Mazandaran wood and paper factory with 400±25 CSF Freeness. In addition to: unbleached importer long fiber pulp with 510±25 Freeness in 5% area mixture with NSSC pulp of factory. (The above pulp was the witness pulp for produce the paper) and produce from one sample of 127 gr/m2 hand sheet paper. At last studied the resistances of hand sheet papers. For study of resistance properties of hand sheet papers, used from TAPPI standard, Studies show that, with increase of using of bagasse pulp, the resistance indicators like that Ring crush Test (RCT), Stiffness, Tensile Strength, Burst Strength, tear Strength, and Breaking make increased.

In this paper, it is attempted to overcome the problem of Wood and Industrial company of Iran by using the diagnosis model of industrial renovation company of Iran by applying EFQM (European Foundation for Quality Management). According to this model and related checklists, various sections of Wood and Industrial company of Iran are concerned. These sections are determined as domains of model and the domains are classified in two categories: The Results and capabilities. The Results are: results for customers, results for the society, key application and finally the results for the employees. The Capabilities areas are: the process and structure and the systems, leadership and organizational culture, the resources and supply chain management, employees and the strategies. After defining the problems and causes and the witnesses were many strategies and guidelines for solving the bottlenecks and crisis classified and predicted as following: First priority: 1-Market research. Second priority: 1-Executive manager (top manager) middle level manager training. 2-Commercial and financial system design and after market services.3-Feasibility study for investment.4-Evaluation of requirements. 5- The implementation many quality systems management for example ISO 9000/2000 and etc.

In this study, chips from Horn Beam and Beech chips pile from Mazandaran Wood and Paper Industries were randomly chosen. Standard chips were separated and washed manually and CMP pulp from two species with 8S% yield was prepared. CMP pulps were bleached separately with DTPA and without DTPA and with hydrogen peroxide. Some of the pulps were bleached with sodium ditionite and hand sheets with 60 gr/m2 gramage were prepared. Then DTPA (0.5%) was sprayed on the hand sheets and hand sheet optical properties were measured by TAPPI standard methods. All the prepared papers went through thermal aging, separately at 0, 10, 20, 30 and 40 hours at 105˚C in oven, and their optical properties, including, their brightness, yellowness, K/S ratio, PC number and their a* factor before and after thermal aging were measured and compared. The results of this study showed that, from 0 to 40 hours, the optical properties of paper except brightness and greenness increased. This increase is more significant up to IS hours. Also, between different treatments, the DTPA treatment in long-term thermal aging and the use of sodium ditionite and hydrogen peroxide in the short-term aging, have important influences on brightness durability and decrease in color reversion. As a result, there is an increase in paper durability against thermal deterioration. The Horn Beam species is more appropriate than the Beech species.

The first period of combustion in a compression ignition engine is the period of ignition delay. The duration of this period plays an important role on performance and efficiency of the engine. Determination and control of parameters that effect the duration of this period is useful in design and improvement of engine performance. Tests were performed using full factorial design of experiments with engine speed in 4 levels: 1200, 1350, 1500, 1650 rpm, engine load torque in 4 levels: 55,70,85,100% and 5 levels of fuel injection timing 22, 27, 32, 37, 42°CA btdc on a small direct injection diesel engine. Engine combustion parameters such as peak cylinder pressure, maximum rate of cylinder pressure rise, maximum acceleration of cylinder pressure, peak rate of heat release, cylinder internal temperature and static and dynamic ignition delay were measured and analysed. The effective parameters on ignition delay were determined and investigated which were cylinder internal temperature, engine speed and peak rate of heat release. Under constant condition of load and fuel injection timing, increasing peak rate of heat release cylinder internal temperature and engine speed, static and dynamic ignition delay were decreased. Under constant condition of load and speed, increasing peak cylinder pressure decreased ignition delay. The effect of cylinder pressure rise, maximum acceleration of cylinder pressure and engine load torque on ignition delay was negligible.

Among air pollutants of diesel engines (including HC, NOx, CO2 and Particulate Matter-PM) the share of PM is about 25 percent. Harmful effects of PM on the environment and human health have put this pollutant to be in a dangerous emission category. Hence, many researchers have been seeking to reduce this type of emission. The opacimeter is a device which measures and monitors the amount of PM and soot in a diesel engine exhaust. A glass tube with four gate was developed and used in the device. The opacimeter is made using optical electronic logic and circuits. Four sensors were tested in three distances (10-12-14 cm) between the sensor and the light source with five replications. Since the sensitivity curves showed good results for the 14 cm distance, this distance was fixed and the test was carried out to find the best sensor among the four. Final results showed that the L14G 1 sensor had the best sensitivity and trend among the other sensors.