JWSS - Journal of Water and Soil Science

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This study was conducted to assess the effect of culturing oyster mushroom (Pleurotus florida) on the nutritive value of wheat straw. In a completely randomized design, chemical composition and in vitro digestibility of untreated and fungal treated wheat straw were measured by the following treatments: 1) untreated wheat straw (UWS) 2) fermented wheat straw before mushroom fruiting (FTWS) and 3) fermented wheat straw after mushroom harvesting (SPWS), with 4 replicates. In addition, the in vivo digestibility and voluntary intake were determined using 4 cows and 4 sheep and nutritive value index was estimated. The crude protein and in vitro digestibility increased whereas organic matter and cell wall components decreased significantly (P<0.05) in FTWS and SPWS. In vivo digestibility and voluntary intake increased in FTWS when fed to sheep or cow (P<0.05) but no significant differences were found between SPWS and UWS. The digestible dry mater and organic mater intake (g/kg W0.75) were significantly higher (P<0.05) in cow than sheep. The significantly (P<0.05) highest amount of nutritive value index was obtained for FTWS fed to cow and the lowest amount was found for SPWS when fed to sheep. It can be concluded that culturing Pleurotus florida on wheat straw can improve its nutritive value before mushroom fruiting .

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Soil structure and aggregate stability affect soil erodibility. There is a necessity for increasing aggregate stability against erosive factors such as wind and water. This study was conducted on surface soil samples (0-20cm) collected from agricultural land susceptible to erosion located in Chahoo, southeast of Fars province. The experimental design was CRD with 10 treatments and was replicated 3 times as follows: control plot (without addition of soil amendments), pure gypsum, chopped wheat straw, farm yard manure, gypsum+wheat straw, gypsum+ farm yard manure (1% w/w), cement at levels (0.3% w/w), (0.6% w/w), (0.9% w/w), gypsum +cement (0.9% w/w). After one, four and seven months, the amounts of soil aggregates in 53-4000 µm sizes were determined by wet sieving and MWD was calculated. The results of aggregate size distribution in every stage of the experiment showed that application of farm yard manure and wheat straw separately or in combination with gypsum through reduction in aggregates with diameters of <106 µm has caused an increase in aggregates with diameter of >106 µm. Based on the results of this research, the effect of these treatments, which increased MWD of the aggregate, results from the amount of aggregates with diameters larger than 1000 µm. According to the results of this study, it is suggested that these treatments be considered suitable to increase the stability of sensitive silt loam soils.

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