Remote sensing of impervious surface growth: A framework for quantifying urban expansion and re-densification mechanisms

A substantial body of literature has accumulated on the topic of using remotely sensed data to map impervious surfaces which are widely recognized as an important indicator of urbanization. However, the remote sensing of impervious surface growth has not been successfully addressed. This study proposes a new framework for deriving and summarizing urban expansion and re-densification using time series of impervious surface fractions (ISFs) derived from remotely sensed imagery. This approach integrates multiple endmember spectral mixture analysis (MESMA), analysis of regression residuals, spatial statistics (Getis_Ord) and urban growth theories; hence, the framework is abbreviated as MRGU. The performance of MRGU was compared with commonly used change detection techniques in order to evaluate the effectiveness of the approach. The results suggested that the ISF regression residuals were optimal for detecting impervious surface changes while Getis_Ord was effective for mapping hot spot regions i n the regression residuals image. Moreover, the MRGU outputs agreed with the mechanisms proposed in several existing urban growth theories, but importantly the outputs enable the refinement of such models by explicitly accounting for the spatial distribution of both expansion and re - densification mechanisms. Based on Landsat data, the MRGU is somewhat restricted in its ability to measure re-densification in the urban core but this may be improved through the use of higher spatial resolution satellite imagery. The paper ends with an assessment of the present gaps in remote sensing of impervious surface growth and suggests some solutions. The application of impervious surface fractions in urban change detection is a stimulating new research idea which is driving future research with new models and algorithms

Effects of Accelerated Aging and Acid Scarification of Seed Coat with Hydrochloric Acid on Seed Germination Characteristics of Chickpea c.v. Kaka

To evaluate the effects of accelerated aging and seed coat scarification with Hydrochloric acid (HCl) on seed germination characteristics of chickpea (Cicer arietinum) c.v. Kaka, a factorial experiment was conducted in completely randomized design with two factors in laboratory condition. Factors were three levels of accelerated aging for zero, 24 and 48 hours by 45°C and 100% relative humidity and 8 levels of Hydrochloric acid treatments of seeds (dry seed as chickpea), immersion in 0 (distilled water), 0.5, 1, 1.5, 2, 2.5 and 3 normal HCl for half an hours. Results showed that accelerated seed aging and HCl treatments both reduced percent and speed of seed germination, epicotyl and root length. Accelerated seed aging increased the negative effects of HCl treatments. Only hydro-priming improved seed germination characteristics in all accelerated aging treatments. On the basis of the results of this experiment, treatment with HCl isn’t a suitable treatment for chickpea seed priming

Responses of Seed Yield, Yield Components and Some Morpho-physiological Traits of Wheat Cultivars (Triticum aestivum) to the Application Methods of Fulzyme Biofertilizer

To study the effect of application methods of Fulzym biofertilizer (containing Bacillus subtilis) on yield, yield components and some morpho-physiological characteristics of four cultivars wheat, an experiment was conducted in field of Astan Quds Razavi in 2010- 2011. The experiment performed was in split plot based on randomized complete block design with three replications. Four wheat cultivars (Falat, Pishtaz, Bahar and Toos) were assigned to main plots and four biofertilizer application methods (as seed inoculation, using in irrigation water, seed inoculation and irrigation and control) to sub plots. Results indicated that Falat had the lowest plant height (61.5 cm) than other varieties. Plant height of Toos and Pishtaz were about 14.5 percent higher than Falat. Application methods of Fulzym increased chlorophyll content and plant height. Highest chlorophyll contents were obtained when seeds inoculated by Fulzyme and used through irrigation. At the end of growing season, it was found that chlorophyll content of Falat and Toos flag leaves were higher than Pishtaz and Bahar. It was also revealed that Bahar when Fulzyme was used showed a better response to treatments than other varieties as for as biological and seed yields were concerned. Highest seed yield produced by irrigation and combination of seed inoculation and irrigation (9063 and 8609 kg.ha-1) and lowest seed yield (5858 kg.ha-1) to Falat in the control treatment

The Effect of Pre-emergence Application of some Common Herbicides on Weed Population, Vegetative Growth, Flower and Corm Characteristics of Saffron (Crocus sativus L.)

Intoduction: Saffron (Corocus sativus L.) as the most expensive crop has special position among export products of Iran. Currently, Iran is the biggest saffron producer and exporter in the world. Much of saffron in Iran produced in South and Razavi provinces (6). One of the problems in saffron production of these regions is weed control. Weed competing with saffron for water, nutrients, light cause reduction of product (3, 7). Among control methods of weed, use of herbicides is not common in saffron fields. The main reason is the evidences about herbicides damage. For example, Zare Hosseini et al (14) observed application of herbicides of Iodosulfuron methyl sodium + Mesosulfuron- methyl+ Mefenpyr-diethyl destroyed grasses and broadleaf, but it destroyed saffron plant too. Haloxyfop- R methyl ester damaged grasses, but decreased stigma yield. This study aimed to investigate the effect of pre-emergence herbicides on weed population changes; the performance characteristics of saffron and saffron corms were implemented. Materials and Methods: An experiment was conducted in a 4-year saffron farm located in Shahn Abad village, Zaveh city in Khorasan Razavi province in 2011- 2012. It was in a completely randomized block design with eight treatments and three replications. The treatments included six pre-emergence herbicides including Metribuzin 70% WP (850 g.ha-1), Oxyfluorfen24% EC (1 l.ha-1), Ioxynil 22.5% EC (1.5 l.ha-1), Etalfluorelin 33.3%EC (3 l.ha-1), Trifluoralin 48%EC (2 l.ha-1) and Chloridazon 80 %WP (5 Kg.ha-1) + Desmedipham 15.7% EC (5 l.ha-1) along with weed free and weedy check. Herbicides applied after irrigation simultaneously with crust breaking. The measurement characteristics included the number of flowers, fresh and dry weight of flower and stigma, leaf dry weight, leaf length, corm number and weight of saffron, weed type and wet and dry weight of dominant weeds. Herbicide treatments after irrigation were performed simultaneously with Crust breaking in 03/11/2011. The flowers gathering were conducted in 03/11/2011. Sampling of weed was performed in two stages in 04/18/2011 and 05/05/2012. In the first stage adding to the collection weed, leaves of saffron are also collected and the length of them were measured. In the second phase, when corm growth was stopped, they were gather, count, weight, and divide by weight. Corms into 4 groups: 0 to 3 g, 3 to 6 g, 6 to 9 grams and 9 grams were divided up. The traits were analyzed by using software programs Mstat-c. Mean comparison carried out with Duncan test with 5% probability. Result and Discussion: The results showed that between herbicide treatments the highest number of flower (16.76 per m-2) and dry weight of stigma (75.67 mg per m-2) was belonged to Metribuzin treatment. The least flowers number (10.76 per m-2) and dry weight of stigma (13.67 mg per m-2) were observed in Etalfluorelin treatment. However there weren’t significant difference between Etalfluorelin and Trifluoralin for these traits. In the first stage of weed sampling were only narrow leaf weeds. In the second stage sampling was 7 species, 3 species of narrow-leaf and broadleaf species was 4. Most of the narrow leaf weed species were ovate goatgrass (Aegilopsgeni culata Roth.). Most broadleaf species belong to maltese star thistle (Centaurea melitensis L.). In the first stage of sampling Metribuzin and Chloridazone+ Desmedipham herbicides had the highest effect in narrow leaf weed control, respectively. Ioxynil had the least impact on this stage. In the second stage of sampling, the highest and lowest control of maltese star thistlewas observed in Chloridazone+ Desmedipham and Ioxynil respectively. Chloridazone+ Desmedipham and Metribuzin had the greatest impact onovate goatgrass and other herbicides for control of these species were not significantly different. Minimal impact on the total corm weight was observed in Metribuzin and Etalfluorelin respectively. The most reduction of corm weight was observed in Chloridazone + Desmedipham treatments. Amiri et al (4) reported that Metribuzin application before and after the weed eruption is appropriate for broadleaves and somewhat narrow-leaves control. None of the treatments had adverse effects on corm weight producing with 0-3, 6-9 and above 9 grams but 3-6 grams weight of corm was affected. In producing corms with 3 to 6 grams weight the least adverse effect was observed in Metribuzin. The most adverse effect after no weeding treatment in producing corms with 3 to 6 grams weight was belonged to Chloridazone + Desmedipham. Conclusion:. On the basis of results, it seems to be due to the least amount of damage to saffron and its corm and the most control of broadleaf and to some extent narrow- leaf weed, the application of 850 grams.ha-1 pre-emergence herbicide Metribuzin is suitable for saffron weed control

Effect of Zinc Chelate Foliar Application on Yield and Yield Components of Four Wheat Cultivars

Application of microelements is one of the ways to increase quantative and qualitative characters of wheat. To evaluate the effect of zinc foliar application on yield and yield components of four wheat cultivars a factorial experiment with two factors was conducted in randomized complete blocks design with three replications in 2011-2012 year. The first factor consisted of four wheat cultivars (Falat, Bahar, Pishtaz and Tous) and the second factor composed of three levels of zinc chelate foliar applications (control, at shooting stage and at shooting + flowering stages). Zinc concentration in each application was decided to be 4 kilogram per hectare. Results showed that yield and yield components of cultivars were significantly different with each others. The highest and lowest yields were belonged to Bahar and Tous respectively. The highest yield of Bahar, as compared to the other cultivars, was due to its higher biological yield. Zinc foliar applications at shooting and shooting + flowering stages also increased biological and seed yields. Seed yield increase mainly affected by higher 1000 seed weight. In general, it seems that zinc application, due to its role in the physiology of wheat, a sensitive plant to zinc deficiency, may increase its seed yield

Studies on the Effect of Type and Solarization Period on Germination Percentage of Four Weed Species

Abstract\ud In order to study the effects of soil solarization on weed control, an experiment with factorial arrangement in a randomized complete block design with four replications was conducted in a fallow farm in Daregaz in 2008. Factors included solarization duration (0, 2, 4 and 6 weeks) and soil moisture content (dry and moist). Soil seed bank was sampled (in two depth, 0-10 and 10-20 cm) prior to the experiment and immediately after applying treatments, and germination percentage of weed species were determined. Results of this study showed that seed germination percentage in 10 cm soil depth was influenced by soil moisture and solarization and their interactions, while in 20 cm soil depth only solarization period affected the weed seed germination. Germination percentage in moist soil was less than that in dry soil. Seed germination percentage declined more by increasing solarization duration, so that the greatest decline was obtained after 6 weeks solarization. Solarization decreased germination percentage in moist soil more than that in dry soil. Overall, the results of this experiment indicated that solarization of moist soil for 6 weeks was the most effective treatment in controlling common lambsquatres (Chenopodium album), common purslane (Portulaca oleracea), redroot pigweed (Amaranthus retroflexus), and wild mustard (Sinapis arvensis), while solarization of dry soil for 2 weeks was the least effective treatment for weed control.\ud \ud Keywords: Solarization, Soil moisture, Seed ban