Sunn pest, Eurygaster integriceps Puton is a key pest of wheat and barley in Iran. In this study, the impact of site-specific spraying on control of sunn pest damage and densities of the natural enemies was compared with the whole-field spraying method in 2009 and 2010. Three plots were assigned to each spraying method and two others were left untreated as control. The plots were divided into 11 9 11 m grids. Adults of E. integriceps were sampled using the distance-walk method. Coccinellids, Chrysoperla carnea and nymphs of sunn pest were sampled using a sweep net. Spatial analysis of datasets was done using Geostatistical Analyst extension of ArcGIS 9.3. The spatial analysis indicated that the adults and nymphs of E. integriceps had aggregated distribution in space and that site-specific spraying was applicable. Whole-field spraying was carried out when the mean density of E. integriceps in plots exceeded the economic threshold. In the site-specific spraying method, decamethrin ([cyano-[3-(phenoxy) phenyl] methyl] 3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropane-1-carboxylate) was applied to the grid cells with densities above the economic threshold. Site-specific application reduced the insecticide input by ca. 40-50%. The numbers of C. carnea and coccinellids were higher in site-specifically sprayed plots compared with whole-sprayed plots after treatment. The mean numbers of nymphs were not significantly different (P \ 0.01) in whole-field and site-specifically sprayed plots. Percent damaged grain was below the economic damage threshold in all treated plots. It can be concluded that site-specific spraying has the potential to control E. integriceps at an acceptable level along with reducing the amount of insecticide used. It also conserved natural enemies in untreated refuges.

Eurygaster integriceps Puton (Hemiptera: Scutelleridae) is the most serious insect pest of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) in Iran. In this study, spatio-temporal distribution of this pest was determined in wheat by using spatial analysis by distance indices (SADIE) and geostatistics. Global positioning and geographic information systems were used for spatial sampling and mapping the distribution of this insect. The study was conducted for three growing seasons in Gharamalek, an agricultural region to the west of Tabriz, Iran. Weekly sampling began when E. integriceps adults migrated to wheat fields from overwintering sites and ended when the new generation adults appeared at the end of season. The adults were sampled using 1- by 1-m quadrat and distance-walk methods. A sweep net was used for sampling the nymphs, and five 180° sweeps were considered as the sampling unit. The results of spatial analyses by using geostatistics and SADIE indicated that E. integriceps adults were clumped after migration to fields and had significant spatial dependency. The second- and third-instar nymphs showed aggregated spatial structure in the middle of growing season. At the end of the season, population distribution changed toward random or regular patterns; and fourth and fifth instars had weaker spatial structure compared with younger nymphs. In Iran, management measures for E. integriceps in wheat fields are mainly applied against overwintering adults, as well as second and third instars. Because of the aggregated distribution of these life stages, site-specific spraying of chemicals is feasible in managing E. integriceps.

Geographic information provides the basis for many types of decisions ranging from simple path finding, to the sustainable management of environmental conditions. Producing such information is a time consuming and costly endeavor. Data sharing on the web is an avenue to increase the efficiency of the practices. This paper scientifically examines the new emerging technologies namely, internet, geographic markup language (GML), and observation and measurement models, to construct an interoperable repository for air quality sensors measurements. The paper also elaborates on the design and implementation of a web-based air quality information system (AQIS) for the city of Tehran. In-situ sensors measure ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2) and particulate matters (PM) in polluted metropolitans. Providing real-time air quality information can improve the decisions of the pertinent environmental organizations. Using GML for encoding sensors observations makes it possible to build an interoperable repository that is independent of platforms and vendors. Providing query possibilities based on monitoring stations, sensor names (pollutants), date and time intervals, and spatial query on the AQIS interfaces are the major functions of this system. Although standardized, it was concluded that the use of GML as data format increases the size of GML document. In addition, the developed system provides no map based results for the clients. Therefore, it is required to be improved by adding more GIS functions.

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Abstract. Urmia Lake has experienced many fluctuations during recent decades, which played a key role in the socio-economic changes in the north-western part of Iran. Consequently, socio-economic planning and land management around the lake require anticipation of changes’ trend. In this paper, regarding continual rainfall in the beginning of 2019, shoreline and water level changes of this lake have been studied and compared to the previous decade. To this aim, Landsat satellite imagery (Oli, ETM and TM sensors’ images) was used to extract NDWI index by using Green and NIR bands. The results of this study showed that Urmia Lake has declined over the past ten years and reached its lowest level in the year 2015. However, due to rainfall of 2019, these changes have had ascending trend which made water area equal to the situation in 2010. It, also was observed that similar to the trend of water level, the shoreline has progressed toward the Lake from the east and the south and become salt marsh. But, the West and the North parts have not changed significantly. Then, in 2019 salt marsh lands have been submerged once again, and the vast eastern island, which was completely blended in with the surrounding lands, returned to its previous state, the peninsula. In addition, considering the trend of rainfall and Lake’s restoring activities, the minimum and maximum time required to reach the area in 2010 were estimated 23 and 38 years respectively, assuming the volume of precipitation remains constant and the reduction of these activities at a constant rate.