Year:2008 | Volume:13 | Issue:2 (SUPPLEMENT)|Papers Count:26

Drought causes damages on rangeland ecosystems, which should be controlled by devising appropriate management measures. Prediction of necessary conditions and effective factors in sustainability of range ecosystem in drought conditions has a great important in management and mitigation of this phenomenon. Thus, the main objective of this research was the investigation and determining the overall situation and factor effecting the sustainability of range ecosystems in drought condition compared to rainy condition in Fars province, Iran. For this purpose an analytical – descriptive research method was used. Population of study included the rangers of Fars province, of which a sample size was taken by using multi- sampling method. Dependent variables of the study included the rangeland situation in drought and rainy conditions and sustainability threat of rangeland in drought conditions and the independent variables was factors affecting the sustainability of range ecosystems during the last five years. The findings of the research showed that there was a significant difference between thirteen indicators (out of fifteen indicators that were studied) concerning the degree of sustainability of rangeland ecosystems in drought and rainy conditions. The finding also indicated that drought had a significant effect on the sustainability of range ecosystem. Based on the research findings the dependent variables of the study including: types of range forage, type of range coverage, type of rangeland, the area of range, drinking water resources for cattle, residence style and the area of orchard garden effected the overall sustainability of rangeland ecosystem in drought and rainy conditions. The research recommended certain measures to be taken for the purposes of drought mitigation including: delivering extension and training programs related to livestock, range and drought, especially before the occurrence of drought, using the indigenous knowledge of range users and using the range in accordance with the principles of sustainable measures.

The purpose of this study was to investigation faculty members' attitude toward new instructional technologies in agricultural education. The methodological approach in this study was descriptive-correlation. The target population in the study was faculty members of education complex of Esfihan Jihad-Agriculture, Iran. Questionnaire is tool for gather of information. Validity of the instrument was established using a panel of experts consisting of senior faculty members in agriculture extension and education. A reliability analysis was conducted, Cronbach alpha value being reported to be 0.78. Finally 54 questionnaires were filled out and analyze. Findings in the study indicated that a majority of faculty members' attitude toward new instructional technologies is considered to be at a "negative relative" level. Cost of instructional technology software and access to information resources are the main problem and benefit mentioned to be faced by the faculty members respectively. Results obtained from pearson' correlation indicate that there are significant relation between use to instructional technologies, acquaintance to instructional technology in formal education and technical knowledge with faculty members' attitude toward contemporary instructional technologies. The results of the multivariate regression revealed that 32 percent if variability in faculty members' attitude toward new instructional technologies stems from technical knowledge.

Agriculture is center for issues of Sustainable Development. Science haven't found substitution for dependency of human race to agriculture for food and subsistence. but synchronous with that, we see injurious effects of intensive agriculture in worldwide in an extensive form (soil erosion, water contamination, loss of biological diversity and etc.). technologies and management functional approaches for decreasing the rate of destruction in natural resources are unavailable, or when they are available, aren't accepted and accommodated by societies. in this article, researcher try to recognize and study various effective economical, social, educational and etc. acquaintances in agricultural extension and research specialists and elite farmers in Esfahan province-selected in 2006-2007-in regarding to acceptance methods of Sustainable Agriculture. Main instrument of the research is questionnaire. findings of the research showed necessity for making emergency and great changes in approaches, policies and alternatives in various sectors of Iranian economic and society- and agricultural system and agricultural information system and specially in Ministry of Jihad Agriculture (MOJA) and its sub-system, namely agricultural extension and research system and other organizations that related to agriculture and rural development, and high interest and awareness of agricultural extension and research specialists and elite farmers about sustainable development issues in agricultural sector for accessing to sustainable agriculture development in Iran.

Natural enemies of pests (parasitoides and predators) usually show different behavior when encountered with two or more prey. The study carried out on behavior parameters of the predatory bug, Orius albidipennis Reuter preying on Onion thrips Thrips tabaci and two spotted spider mite Tetranychus urticae, 2nd instar larvae of onion thrips and adult female mites were used as preys. Experiments were conducted as Completely Randomized Design (CRD) by replacement of the preyed hosts with two tests choice and non- choice. In two choice test predation rate of the female predatory bug on onion thrips and spider mites were 2.4±0.4 and 1.4±0.35, respectively, which didn't show significant differences but parameters of encounter rate, succes rate and handling time (s) on onion thrips were 0.36±0.06, 0.69±0.12 and 636±22, respectively. These data for two spotted spider mite were 0.11±0.03, 0.36±0.11 and 300±77.6 in which, there were significant differences among between them. In non-choice tests, predation rate of the predatory bug on 2nd instar larvae of onion thrips was 2±0.31 and on two spotted spider mite was 2±0.44 which didn't show significant difference. In these tests, encounter rate, success rate and handling time parameters of the predatory bug on onion thrips were 0.13±0.01, 0.7±0.08 and 948±33.6 and for two spotted spider mite were 0.08±0.02, 0.45±0.09 and 522±62.6 which observed significant differences among them.

In modem biosystematics, biochemichal and morphometric basis are fundamentals of evolutionary taxonomy which its biotechnology shows the intrapopulation evolution in different environmental and mass-rearing situations in comparison with natural host population in agroecosystems. Our research program was based on enzymatic study and in comparison with morphometric results identification of Trichogramma brassicae Bezd, Parasitoids of rice stemborer (Chilo suppressalis WLK.) and com stemborer (Ostrinia nubilalis var: persica HBN,) in different fields of Mazandaran, also in comparison with different population of Trichogramma brassicae feeding on mass-rearing host, Ephestia kuehniella Zell Morphological characters of T. brassicae were studied by means of male genitalia and antennae. Electrophoretic technique have been used for enzymatic study. Polyacrylarnid gels molded between glass plates. For enzyme polymorphism included 12 populations, 20 adults descendants of virgin females in which esterases (EST) were analyzed. The genetic identity distances were calculated based on Nei (1972) method. Based on dendogram, difference between natural and mass-reared populations were observed. Results from enzymatic and morphometric investigations indicated that there is significant differences (95%-99%) between these populations. The efficacy of biological control is dependent on the quality of the T. brassicae. Quality control has always been an important factor in biocontrol. The selection of suitable and adaptive species, quality of mass-reared and climate conditions at the time of release are the main factors that determine the efficacy of using Trichogramma brassicae in Mazandaran. In the other hand for utmost effect, we have to improve the quality control.

Phytoremediation is an emerging technology which uses plants and their associated rhizospheric microorganisms to remove contaminants from soil. Phytoremediation is relatively inexpensive technology compared to technologies that involve the use of large scale energy consuming equipments. Heavy metals are one of the most common contaminants at hazardous waste sites. Of heavy metals, lead (Pb) is one of the most significant contaminant, posing serious and sometimes life threatening health hazards. The objective of this study was to investigate the potential use of Land Cress to remediate Pb contaminated soils. Consequently, a large quantity of a sandy loam soil was thoroughly mixed to ensure homogeneous concentration levels of 0, 15O, 300, 600, 800, 1000 and 1500 mg Pb kg-1 soil by lead. These contaminated soil treatments were transferred to some plastic pots. Land Cress seeds were germinated in pots containing 8 kg of lead contaminated soil. The concentrations of Pb in the soil and plant samples have been determined by flame and graphite furnace atomic absorption spectrometry. The results indicated that the Pb concentration of Land Cress was increased by increasing Pb concentration in the soil samples. Also, the relative yield of Land Cress was decreased by increasing Pb concentration in the soil. The results were also indicated that the remediated amount of Pb was increased by increasing soil Pb contamination up to 1000 mg kg-1. However, it decreased in the soil Pb contaminations between 1000 to 1500 mg kg-1. Results showed that, although, Land Cress tolerates the high levels of soil Pb contamination, it is not of potential to phytoextract such pollutions. Results, therefore, suggest that Pb-phytoremediation using the Land Cress is not feasible when the soil is highly contaminated. However, Land Cress has the potential to remediate low levels of soil Pb contamination.

The Penman-Monteith method is the most common equation for estimating reference crop evapotranspiration. But, this method needs many weather parameters. In this study, by using the weather data of Shiraz synoptic station from years 1959 to 2000, four versions of Hargreaves equation were compared with Penman-Monteith method. The results indicated that the original Hargreaves equation was the worst, and the version included monthly rainfall, was the nearest to the Penman-Monteith method. Therefore, the version of Hargreaves with mean monthly minimum and maximum temperature and monthly rainfall, can be used for estimating monthly evapotranspiration in Shiraz region instead of Penman-Monteith method. The important advantage of using this equation is to need less weather parameter. Also, this equation can be used in conditions that some weather parameters were not measured.

Poor irrigation water management combined with inadequate drainage infrastructure renders irrigated areas at risk of becoming waterlogged and gradual build up of salt concentration leading to soil degradation in arid and semi-arid regions. The objective of this review article is to recognize two main and new subjects in drainage issues: Integrated approach and impacts of climate change. The drivers for a change towards an integrated approach to drainage are: increasing complexity of water control systems; conflicts of interest in many water management systems; re-prioritization of land and water management objectives because of changing social values; and declining luster of drainage as a professional sector and the need for the professional drainage community to rethink its position. On the basis of this analysis of the present situation with regard to drainage, a new and broader definition of drainage, less exclusively focused on agricultural productivity, can be formulated as a first step towards an integrated approach: "Drainage is land and water management through the processes of removing excess surface water and managing shallow water tables - by retaining and removing water-with the aim of achieving an optimal mix of economic and social benefits while safeguarding key ecological functions". Moreover, drainage systems were designed for a long life, on the assumption that climatic conditions would not change in the future. This will not be so in the years to come, due to the global warming and the greenhouse effect. Although an anthropogenic ally-induced climate change is expected to have significant impacts on drainage systems, the range of uncertainty as to how these climate impacts, at the geographic scales of interest, affect the drainage development process is still great. Moreover, the absence of a uniform understanding makes it difficult to assess the adequacy of existing planning principles and design criteria, in the light of these potential changes. Therefore, planners, designers, researchers and decision makers need to review the strengths and weaknesses of current trends in drainage development and rethink technology, institutional and financial patterns, research thrust and manpower policy, so that service level and system efficiency can be improved in a sustainable manner. At present, the challenge is to identify short-term strategies to face long-term uncertainties.

Conceivably no major food crop other than wheat can compete with rice in the range of climatic and hydrologic conditions under which, it is grown. Rice is produced in every continent except antarctica and thrives in an area ranging in latitude from 55o to 40o. It grows as a dryland crop much like wheat or maize, as a rainfed crop under alternately submerge and dry conditions, and as a continuously flooded crop. Farmers grow rice on alluvial plains, flooded valleys, and terraced hillsides. Even though it has less drought tolerance than other cereals, rice grows well in arid areas under irrigation such as in Asia and north Africa. Likewise, despite rice's sensitivity to low temperature, yields are high in northern Japan and China and at elevations of more than 3,000 meters above sea level in the tropics and subtropics. Most paddy soils are located at lower positions in landscapes to permit water easy access from higher irrigation or natural surface runoff sources. These wetland rice areas may be flat-bottomed valleys or terraced and bounded hillsides of otherwise upland areas. But more often, they are found in alluvial flood plains, deltaic plains, coastal plains, tidal flats, marshes, and major river valleys. Such areas are generally characterized by a natural or induced "aquic" moisture regime that implies high moisture and low oxygen conditions. As a consequence of this high moisture-low oxygen requirement, the soil characteristics for paddy rice culture may vary less than those for upland or dryland rice.

One of the management optimal water consume in farm, is accurate estimation plant water demand and how time trend reference evapo-transpiration study and research reference evapo-transpiration for considering interest cultivation pattern and optimization by water resources is necessary in future. On basis of country expansion, variety time trend reference evapo-transpiration and a few inquiries the subject, research the parameter time trend analysis is very necessary and it is the main purposes. After the collecting statistics and data 33 synoptic stations with record lengths 40 year to calculated reference evapo-traspiration to FAo-Penman-Monteith method, and time trend the parameter in monthly scale for every station in 2 record lengths time (40 years) and short time (20 years) to be calculate by slope line trend meaningful test and Spearmans Rank correlation. In short, predicate that record lengths 40 years in average 38% of station have positive trend and 62% have been negative trend, and in record lengths 20 years, 62.5% have been positive trend and 37.5% have been negative trend, that with decrease record lengths deducted of levels negative trend and is increased to positive trend. Also, in record lengths 40 year, reference evapo-transpiration in April was more than 60% stations have positive trend and in March, October, November months was more than 75% stations have negative trend but, in record lengths 20 years, in many of year, reference evapo-transpiration was more than 60% stations have increased trend.

The objective of this study was to determine the growth potential of Ghezel male lambs that fed with four levels of pasta industrial by-products containing: 0, 5, 10 and 15 percentages in diets. Diets were formulated isocaloric and isonitrogenous. Twenty Ghezel male lambs with around 7-8 months old and 36.8l±3.17 kg initial average weights were used for a fattening period of 90 days. This experiment conducted in randomized complete blocks design (RCBD) with four treatments and 5 replications in each treatment. Feed and water were provided ad-libitum for all of the lambs during the experiment. Individual feed consumption and body weight of lambs were measured at two weeks intervals. Significant differences were not found between treatments in total dry matter intake (p>0.05). Significant differences were found on the rate of daily weight gain and feed conversion between treatments (p<0.01).The highest daily weight gain along with the best feed conversion rate were found in group3 animals with 10 percentage pasta industrial by-products, although The differences between group 3 and group 4 animals were not significant. In conclusion it seems that, pasta industrial by-products could be used as an energy source up to 15 percentages of the male Ghezel lamb diets without any adverse effects on performance.

To study the rate of absorption and translocation of 2, 4-D during different growth stages of Red Root Pigweed, Common Lambsquarters & Common Purslane, this experiment was carried out at the Nuclear Research Center for Agriculture and Medicine in Karaj (1382-83). Four different growth stages of weeds (including: 4 and 8 leaf stages, starting of reproductive stage and flowering) were produced under the green house condition. leaves inoculated by labelled 2, 4-D with activity of 0.08 µCi (in each 10 µli of solution), through the adaxial surface. extraction and counting of labelled herbicide showed that, absorption and translocation of 14C2, 4-Dat Common lambsquarters is the lowest rate and at Common Purslane is the highest. Rate of 14C2, 4-D translocation was significantly different during growth stages of Red root pigweed and Common lambsquarters. Rate of translocation decreased in Reproductive stage but sensitivity to 2, 4-D increased during this growth stage.

In order to spraying micronutrient elements on the grain yield and yield components of 704 com hybrid an experiment was carried out in two years (2003, 2004) in research farm situation of Khoy. The experiment was done in spilet plot design by random complete block design (RCBD) base in three alternation. The times of foliar nutrition in three level (T1=Steme extention stage, T2=Tasseling and T3=Stem extention + tasseling) were main plots and kind of fertilizer that used were subordinate plot included 8 levels (F1 absence of fertilizer usage, F2 spraying iron, F3 spraying zinc, F4 spraying manganese, F5 spraying iron + zinc, F6 spraying iron + manganese, F7 spraying zinc + manganese, and F8 sprayingiron + zinc + manganese). the result of variance analysis showed that except the ear height to stem height ratio, ear wood weight and harvest index, the other experimental featuers of the test were meaningfully under the influence of fertilizing treatment times. So that the highest grain yield the respectively 11.52 tons per hectare obtained in T3 treatment it also had the highest function of ear longth, ear diameter, ear row numbers, grain in ear rowes, ear grain number and 1000 number grain weight. The results of this survey shows that kind of fertilizer had meaningfully effect on ear height to stem height ratio, ear longth, ear diameter, ear grain rowes, grain in rowes, grain in ear, 1000 grain weight, ear wood weight and harvest index. However thr highest grain yield by 12.18 ton per hectare obtained in F8 treatment (Fe + Zn + Mn) that had 34.3% higher than control treatment. the fertilizer kind cuold affected to all experimental featuers.

To study the effect of plant density and N-fertilizer on seed and active substance yield an experiment was conducted in spring of 2005 at research station of Hammand Absard in Damavand. The treatments were plant spacing in 3 levels (50x20, 50x30, 50x40 cm) and N-fertilizer in 4 levels (0, 50, 100, 150kg/ha).During ontogenesis, the growth and development in each treatment were recovered and after collecting and drying the fruits, seed yield and silymarin percentage was measured. The results show that increasing N-fertilizer and plant density has a positive effect on seed yield, although the seed yield of each plant was decreased by increasing the plant spacing. The percent of effective substance of seed (Silymarin) didn't show any difference in plant density but in 0 kg N/ha, the active substance was higher than another plant which received difference levels of N-fertilizer, althought finally highest yield of silymarin was obtained in plant with highest density which received highest level of N-fertilizer.

Pollution of agroecosystems to heavy metals and others contaminants and continuously, their translocation to food web and ultimately human is a global problem. These contaminants cause many problems for human healthy. Meanwhile, these pollutants have harmful effects on environment and it is biocense and zoocenose. To clean up contaminated soils, many methods has developed. But, up to now environmentally base and environmentally sound approaches apply in commercial level. Phytoremediation is ecological and ecofriendly approaches that environmentally friendly and cheaper than physicochemical methods and also have ability of remediation soil, water and air contaminated. Application of biodiversity such as, plants, algae, fungus and bacteria in this approach is a key factor. In this article we review the impacts of these contaminants on agroecosystems and human healthy and wealthy and use of mycorrhizoremediation technique to clean up these soils.

Particleboard industry has high and special opportunity among wood industries because of using of cheaper Lignicellulosic materials, production of mutiple products and high efficiency. With regard to present study has been determinated that the industry has high growth rate and production capacity increase with respect to establishment of New plants in recent years. At present in the country there are 20 active factory in nominal capacity of 736100m. 3 Production, import, export and consumption of the product (particleboard) has changed in year of 1383 (2005) and the amounts of the above cases were 641866m3 (%83 nominal capacity), 33475m3, 13100m3 and 662241m respectively. 16 of the Factories has used firewood and their needs is 950040m3. With regard to decrease of wood harvest from North forests from 1995 to 2005, the factories has had big problems to procure of wood row material (Amount of fire wood has been produced only 299213m3 in 2005) Almost, the productivity of the factories has been lower because of raw material shortage, no skilled human force and ancient technology of machines. Of course there are several problems in the factories, for example: high production costs, Low quality of the products and poor competation in compare with imported replacement productions (particleboard and MDF). Accordingly to solve the problems and to abtain proper production positions it will be essential to do accuracy programming in fields of raw material procurement, applying of skilled human forces and staff training and machines substitution.

Radiation, as a means of food preservation, was first discussed in 1905. In this method, food is exposed to a certain doze of ionizing ray with the purpose of destroying or deactivating microorganisms and insects, delaying the procedure of ripening of fruits and vegetables, preventing glandular and root vegetables from new shooting, and in general, increasing the period of preservation under certain conditions.

In this research, three samples of the wastewater from famous industrial factories of Isfahan have been chosen. After specifying the amount of heavy metals, resistant bacteria have been isolated and the pattern of their resistance was assigned by MIC. Multi metal resistance has also been examined. According to the acquired results, the greatest resistance has been related to the Zn. It's maximum MIC in the second and third wastewater is 24mM that's related to the such bacteria as Coryne bacterium, Entrococcus faecalis and it's minimum MIC is 8, 12mM that's of Citrobacter and some of Bacillus. The minimum degree of resistance is related to Cu. It's maximum MIC in the second and third effluent is 4mM of Moraxella, Pseudomonas and it's minimum is arranged as 1mM related to Klebsiella pneomoniae an 2mM related to the genus of Bacillus, Providencia and Staphilococcus aureus. In examining multi metal resistant, all isolates have shown resistance to Cd, Pb and Zn (except one case). Most of resistant isolates are gram positive excluding Cu resistant bacteria.

The hydrophytes (waterweed) complete their biological cycle in three forms: located under the water, floating on the water and above the water, and if we don' t care and management them, they can grow irregular and it will be damage water-life. Different specieses of these plants such as Azolla, have grown and have bred, according to proper physiological circumstances in all parts of the world and various water- environments. Azolla is one of the waterweeds that is flooted on the water and it is native in Africa and southeast asia. IT was distributed in Anzaly marsh and logons that located in north of Iran, by reason of lack of management purposes in agricultural and industrial uses, in 1363, and now it has made a mantle (cover) on the Surface of water, and instead of efficiency, it has Converted to a destructive factor (agert). Sofar, many researches have published in relation to application and it's bad effects on environment of biology and ecosystem of north of Iran, but no practicable (practical) function, has been done for particular studing of created damages, and it's optimum control. This paper is on the basis of studing research and it has been perfamed on the basis of methodology of library studings, searching of extraneous (outsider) Sources, scope observations and analysis of information, and the results have been giren in the form of descriptive and resolutive In this paper, status of Anzaly marsh has been studied with the view of vast attack of this plard, to identify, and logical manners to encounter this problem. In this paper, the concept of "management of waterweed" has been presented and emphasized on it's usage for Keeping of water sources in north of Iran. One of the main characters of this management is the prevention ond control manners (in form of sole or incorporation). Presentation of harvest machines of waterweed, such as Azolla, under the title of one of the effective methods for controling these plants and reformation of existent status, is one of the results of this research.

Studies of planktons, in particular studies focusing on the diversity and density of phytoplankton existing in water resource, are the most basic studies in the realm of ecology and related environmental studies. For the length of six months period starting from Farvardin ending in Shahrivar 1384 (representative of two different ecological seasons, namely spring and summer), Some water samples were taken from six site stations located in Abbaspour Reservoir using the standard methods, The sample comprised of surface water and deep water (often meters in depth). This study also has investigated and measured the existence of Abiotic factors in water such as nitrates, phosphor, oxygen, opaqueness, TDS, water temperature, EC and water salinity, Subsequently the study has examined the effect on the composition of phytoplankton of each of these factors. During this sample survy, 16 Genus from 13 families belonging to five phylum of phytoplankton were identified. Of these species, sixbelonged to phylum of bacillariophyta, one to chrysophyta, four to cyanophyta, four to dinophyta and one to chlorophyta. The survey results indicate that phylum of dinophyta demonstrated the largest density of phytoplanktons in two seasons while the phylum of chlorophyta showed the least density. The spring survey result indicates that the phylum of bacillariophyta gets second rank after dinophyta phylum, while the finding for the summer survey show that members of cyanophyta phylum rank second after Bacillariophyta in terms of density of planktons. The result of study on Abiotic Factors and their effects on phytoplankton indicate that the Abbaspour Reservoir can be considered relatively fertile (oligo-mezotrophic). As such, if adequate care is taken to protect this reservoir with modem technique. One can advocate the feasible nature of Abbaspour Reservoir for the extension of aquaculture activities particularly in the light of abiotic factors existing in the reservoir.