Hydrochemical processes and metal composition of Ain Umm-Sabah natural spring in Al-Hassa Oasis Eastern Province, Saudi Arabia

This study was carried out to determine the hydro-chemical processes and the metal concentration of spring water to evaluate its suitability for irrigation and other purposes. A total of 10 water samples were collected from Ain Umm Sabah at different times and from different locations from the spring basin. EC (dS m(-1)), pH, temperature, total cations (Na, Ca, Mg, K) and anions [Cl, CO3, HCO3, SO4, NO3, Fluoride (F)] were determined. Some trace and heavy metals (Al, As, Ba, B, Br, Mo, Ni, Si, Cd, Cu, V, Fe, I, Pb, Mn, Zn, Sr, Se, Sb, La and Se were determined. The Spring water is classified as C4S2 (high salinity with medium sodicity problem water). Chloride (Cl) and nitrate (NO3) concentrations were higher than the permissible limits according to World Health Organization Standards. The Ain Umm Sabah water is Na-Cl dominant water and can create soil sodicity problems and cause Na and Cl ion toxicity to plants if used for irrigation of sensitive crops. The spring water is under-saturated (negative SI) with respect to calcite, dolomite, gypsum, anhydrite, halite, fluorite and aragonite and oversaturated (positive SI) with respect to goethite, siderite and hematite minerals. The concentration of all the estimated trace metals was within the permissible limits for its use as drinking water and other purposes according to WHO. Since the spring water contains high concentration of NO3, hence can not be used for drinking purposes without prior treatment. The study findings suggest careful use and pumping of water from the spring. Further studies are required on regular basis to monitor the depletion in the spring water level and the temporal change in water salinity.     

Rice husk biochar application to paddy soil and its effects on soil physical properties,plant growth,and methane emission

The objective of this study was to investigate the effects of the application of rice husk biochar on selected soil physical properties, rice growth, including root extension, and methane (CH₄) emissions from paddy field soil. Three replication experiments were conducted using outdoor pot experiments utilizing commercial rice husk biochar mixed with paddy soil at a rate of 0 (control), 2, and 4 % (weight biochar/weight soil) in which the rice was cultivated for 100 days under a continuously flooded condition. The physical properties of soils were analyzed before and after the growing periods. Some parameters of rice growth and CH₄ emissions of paddy soils were monitored weekly during the experiment. Root extension was also analyzed after harvesting. The experiments showed that the application of rice husk biochar improved the physical properties of paddy soils. It led to a decrease in bulk density and an increase in saturated hydraulic conductivity, including the total pore volume as well as the available soil water content. The shoot height of rice plants was significantly higher in soil amended with 4 % biochar than that in the control soil. However, other plant growth parameters and root extension were only slightly affected by the application. It was also found that amending soil with biochar led to a reduction of the total CH₄ emissions by 45.2 and 54.9 % for an application rate of 2 and 4 %, respectively, compared with the control. Our results showed that the higher the application rate, the stronger the effect of biochar was observed. More research is still necessary for a better understanding of the underlying mechanisms.     

Light and electron microscopic study on a haemogregarine species infecting the viper cerastes Cerastes gasperitti from Saudi Arabia

A Haemogregarine sp. infecting the Viper Cerastes cerastes gasperitti (35%) from K.S.A. was recorded for the 1st time. Parasites were recorded exclusively in the red blood cells of the Vipers. Erythrocytic parasites measured 17.5 x 3 microm with a nucleus of 8.1 x 2.5 microm. Mature Schizonts of 30 x 2.5 microm and producing 18-30 merozoites by ectomerogony were reported in the endothelial cells of blood capillaries of different internal organs (liver, spleen and lung). The merozoites measured 13 x 3.5 microm and these were similar to the stages in the red blood cells. The motile stages of the parasite recorded in the present study showed all the general architectures of the Apicomplexa with some pecularities such as presence of micronemes and rhoptries at both sides of the nucleus and the occurance of large number of subpellicular microtubules (80-90) extending to the posterior end of the parasite.     

Different effects of earthworms and ants on soil properties of paddy fields in North-East Thailand

As soil engineers, earthworms and ants play major roles in soil functioning, especially in modifying soil physical and chemical properties. This study was conducted in a very constraining environment, i.e., paddy fields which have anoxic conditions (approximately four months per year), and which are affected by soil salinisation during the dry period (approximately eight months per year). This study points out that despite those very adverse conditions, soil invertebrates must be taken into account in the dynamic of soil organic and mineral properties in paddy fields. The effects of one earthworm species, Glyphodrillus sp., and an ant species, Epelysidris sp., on soil physical and chemical properties were determined through elemental soil physical and chemical properties (texture, pH, conductivity, C and N contents) and near infrared reflectance spectroscopy (NIRS) in order to evaluate their ability to influence soil organic matter quality. PCA processed with NIRS data clearly showed that biogenic structures (ant sheetings and earthworm casts) were separated from the control surrounding soil. Earthworms and ants affected differently soil properties. Glyphodrillus sp. increased the SOM content and decreased the pH on the surface of the soil. These effects were attributed to an increase in fine particle content (clay). Conversely, Epelysidris sp. only increased the content of coarse particles (sand) and did not influence either soil pH or SOM content. Soil conductivity was found to be very variable but was not significantly affected by soil invertebrates. These results show the potential of soil macro-fauna to create heterogeneity at small spatial scale and to modify the quality of surface soils even under adverse conditions like saline paddy fields.     

杭州满觉陇茶区土壤特性与西湖龙井茶品质关系研究

选取西湖龙井茶一级保护区内满觉陇茶区五块不同海拔、朝向、质地的土壤,测定其含水率、容重、三相比等基本特性,以及p H值、有机质、全氮、有效磷等养分状况,并对各地块生产的狮峰龙井茶叶品质成分进行测定分析和感官审评。结果表明:满觉陇茶区土壤质地都适宜种植茶树,土壤肥沃,有机质、全氮和有效磷含量较高,其中4#地块土壤特性最好,有机质为50.20 g/kg,全氮为3.35 g/kg,有效磷为91.58 mg/kg,部分土壤保水保肥能力稍差。不同地块产出的狮峰龙井茶叶品质都较好,内含物质丰富,水浸出物达53.21%-56.76%,氨基酸含量为4.37%-6.53%,感官审评认为4#地块生产的狮峰龙井茶品质最好,因此证实满觉陇茶区狮峰龙井品质优且相对一致,土壤有机质含量及养分充足茶园所生产西湖龙井茶品质较好。     

尿素及磷酸二铵对黑土区甜菜生长发育的影响

选用生产上广泛应用的尿素、磷酸二铵为试材,探讨肥料对黑土区甜菜株高、出叶速度、叶面积、根重、含糖率、净光合生产率的影响,为指导合理施肥提供理论依据。试验结果表明,尿素对甜菜株高、叶片数、叶面积、根重等影响较大,磷酸二铵对其影响较小;尿素对根产量的增产作用约是磷酸二铵的2 倍;尿素、磷酸二铵配合施用效果最好。     

Physical soil properties and slope treatments effects on hydraulic excavator productivity for forest road construction

Effects of moisture, porosity and soil bulk density properties, grubbing time and terrain side slopes on pc 220 komatsu hydraulic excavator productivity were investigated in Miana forests road construction project which located in the northern forest of Iran. Soil moisture and porosity determined by samples were taken from undisturbed soil. The elements of daily works were measured with a digital stop watch and video camera in 14 observations (days). The road length and cross section profiles after each 20 m were selected to estimate earthworks volume. Results showed that the mean production rates for the pc 220 komatsu excavators were 60.13 m3 h(-1) and earthwork 14.76 m h(-1) when the mean depth of excavation or cutting was 4.27 m3 m(-1), respectively. There was no significant effects (p = 0.5288) from the slope classes' treatments on productivity, whereas grubbing time, soil moisture, bulk density and porosity had significantly affected on excavator earthworks volume (p < 0.0001). Clear difference was showed between the earthwork length by slope classes (p = 0.0060). Grubbing time (p = 0.2180), soil moisture (p = 0.1622), bulk density (p = 0.2490) and porosity (p = 0.2159) had no significant effect on the excavator earthworks length.     

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia, 1: Anatomy of Samh Seed

The seeds of Samh (Mesembryanthemum forsskalei) are Ostensibly Campylatropous as they seem externally anatropous but internally they have a curved embryo and both the seed body and the funicle exchange shapes. The embryo occupies a cylindrical seed body and is surrounded by a thin layer of endosperm; the major part of the endosperm occupies an ovoid bulge resembling a seed body.     

A novel DDPSi-FR flame retardant treatment and its effects on the properties of wool fabrics

A novel flame retardant monomer DDPSi-FR containing organophosphorus and silicon was prepared using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), 4-hydroxybenzaldehyde (HBA), and 3-glycidoxypropyltrimethoxysilane (GPTMS). The chemical structure of DDPSi-FR was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Subsequently, after treating the wool fabrics, the effects of the monomer on the flame retardancy, thermal stability, and mechanical properties were studied. The flame retardant and thermal properties were evaluated by conducting vertical flame tests, limiting oxygen index (LOI) determination, and thermogravimetric analysis (TGA). The results showed that improved flame retardancy and thermal stability were achieved. Notably, the flame retardancy was retained even after 15 washing cycles. The mechanical properties were evaluated using the bursting strength, and the results indicated that DDPSi-FR treatment improved the breaking strength.     

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia: 2: Chemical composition and microflora of samh seeds

The chemical composition of samh seed have been investigated. Proximate analysis showed a composition of 22.25% protein, 5.7% moisture, 5.6% fat, 4.0% ash, 9.7% crude fiber, and the remainder being total carbohydrates. Mineral element analysis revealed that potassium, magnesium, sodium and calcium were present as the major elements. Iron, manganese, zinc and copper were found at lower levels. However, lead was not detected in the samh seeds. Gas-liquid chromatographic analysis of the methylester of the fatty acids of the samh seeds oil revealed the presence of fourteen fatty acids. Linoleic and oleic acids were the principle unsaturated fatty acids. While palmitic acid was the main saturated fatty acid. Amino acid analysis of the samh seeds showed the presence of seventeen amino acids including eight essential amino acids. Glutamic acid, arginine, and aspartic acid were the major amino acids. Cystine and proline were present in trace amounts. These results some of which have not been reported elsewhere indicate the high nutritional potential of Saudi samh seeds. The total aerobic bacterial count and total sporeformers of seeds were 19×10⁷ and 5×10⁴ cfu/g respectively, thus the enterobacteriaceae,B cereus and yeast and molds were 5×10², 1×10² and 7×10² respectively. The seeds were Staph. free and the samh extract had no antimicrobial effect.     

Viscoelastic properties and bubble structure of rice-gel made from high-amylose rice and its effects on bread

Rice gel is a novel form of processed rice, where gelatinized rice is sheared at high speed to create a gel with unique viscoelastic properties, which can partially replace wheat flour in bakery products. In this study, the viscoelastic properties and bubble structures of rice gels made from two high-amylose rice cultivars and two different ratios of rice to water were studied, focusing on the effect of cooling the gelatinized rice before high-speed shearing (cooled rice gel) as opposed to shearing the gelatinized rice while hot (hot rice gel). Increasing the water content and cooling the rice before high-speed shearing generally decreased the dynamic storage (E′) and loss moduli (E″) in the viscoelasticity measurement and introduced fewer but larger and uniform bubbles in the rice gel. In addition, breads made from cooled rice gel showed significantly higher volume than those made from hot rice gel. The application of mechanical shearing to gelatinized starch has a great potential in creating novel food materials with characteristic textures, and can also be used for the processing of cereals other than rice.     

盘锦地区耕地土壤养分情况简述

2001年开始,盘山县在耕地土壤上采集了578份监测土样,对土壤有机质、全氮、碱解氮、有效磷、有效钾和pH值等进行化验分析。结果表明,在1982年～2001年的20年间,全县耕地土壤的全氮、速效磷含量水平有所提高,有机质和速效钾的含量呈下降趋势。     

The effects of treading by dairy cows on soil properties and herbage production for three white clover‐based grazing systems on a clay loam soil

White clover can reduce fertilizer‐N requirements, improve sward nutritive value and increase environmental sustainability of grazed grasslands. Results of previous experiments in glasshouse conditions and on mown plots have suggested that white clover may be more susceptible than perennial ryegrass to treading damage on wet soils. However, this phenomenon has not been investigated under actual grazing conditions. This experiment examined the effects of treading on clover content, herbage production and soil properties within three clover‐based grazing systems on a wet soil in Ireland for 1 year. Treading resulted in soil compaction, as evidenced by increased soil bulk density (P < 0·001) and reductions in the proportion of large (air‐filled) soil pores (P < 0·001). Treading reduced annual herbage production of both grass and white clover by similar amounts 0·59 and 0·45 t ha^?1 respectively (P < 0·001). Treading reduced the sward clover content in June (P < 0·01) but had no effect on annual clover content, clover stolon mass or clover content at the end of the experiment. Therefore, there was little evidence that white clover is more susceptible to treading damage than perennial ryegrass under grazing conditions on wet soils.     

Evaluation of two types of superabsorbent polymer on soil water and some soil microbial properties

Paddy and Water Environment - In this study, two types of superabsorbent polymers, Luquasorb (Luqua) and Stockosorb (Stock), at 180&nbsp;kg&nbsp;ha−1 were applied by scattering and...     

Fertilization management of paddy fields in Piedmont (NW Italy) and its effects on the soil and water quality

The fertilization management of the rice crop in Piedmont was analyzed at a regional scale, and the agronomic and environmental sustainability of the actual fertilization strategy of rice was evaluated through the analysis of its effect on the soils and waters quality. On average, a total amount of 127 kg ha⁻¹ of N, 67 kg ha⁻¹ of P₂O₅ and 161 kg ha⁻¹ of K₂O were supplied to the rice crop. In most cases N and P fertilization was rather well balanced with crop removal. The N balance was in the range ±50 kg for 77% of the surface. The low concentration of N in the groundwater reflected the small N surplus. P fertilization resulted to be smaller than removal for 53% of the surface. Nevertheless, the soil extractable P was very high, probably because of former higher P inputs. This resulted in a high concentration in water courses and aquifers. The K fertilization was excessive (surplus >100 kg ha⁻¹) for 53% of the surface, but most soils showed a low K content. K is probably contributing to nutrient leaching to a great extent. The average soil organic matter (SOM) content of paddy fields was higher than that of normally-cultivated soils in Piedmont, and the C/N was higher, owing to the low mineralization rate in waterlogged conditions. The SOM content was in relation with the management of the crop residues, as the tradition of burning straw after harvest was still widespread on 65% of the paddy surface.     

Irrigation and soil temperature effects on Russet Burbank quality

Potato growers in the Pacific Northwest suffer large economic losses in seasons with above normal temperatures, due to excess reducing sugars in tubers, which cause dark-end French fries. Our objective was to study irrigation management effects on potato quality, particularly the factors causing dark-end French fries or sugar-end syndrome. Solid-set sprinkler irrigated plots were established on potatoes at Kimberly, Idaho during the 1987, 1988 and 1989 irrigation seasons, and at Parma, Idaho in 1987 and 1988. Irrigation treatments were high and low frequency (3/week and I/week) and two or three water application amounts referenced to estimated evapotranspiration (ET, ET+20%, and ET-20%). Neither frequency nor amount significantly affected yields. Irrigation frequency had more influence on potato quality than application amount. More frequent irrigation produced slightly higher quality tubers and lower incidence of dark-ends when fried. Soil temperature was inversely related to tuber grade quality and directly related to percentage of sugar-end tubers. Soil temperature was about 0.5 C lower under the high frequency than under the low frequency irrigation regime. On these silt loam soils, allowing available soil water to decline to 50 percent had no adverse affect on yield or quality.     

Studies on samh seeds (Mesembryanthemum forsskalei Hochst) growing in Saudi Arabia: 3. Utilization of samh seeds in bakery products

Samh seeds obtained from Al-Jouf area were ground into flour analyzed and used as a replacement for wheat in the ratio of 10, 20 and 30% for bread and 30, 60 100% for cookies. The rheological effect of the Samh flour on Saudi wheat flour was also studied. The bread and cookies obtained were evaluated physically and by sensory evaluation. The results obtained indicated that samh flour has high protein content and could be used as a replacement for wheat flour upto 30% without adversely affecting the bread specific volume much. Samh flour has improved the cookies appearance specially the colour (chocolate colour) and spreading ratio. The results also revealed that it is possible to make cookies from 100% samh flour. Due to the high protein content of the samh seeds the nutritional value of the bread and cookies made with samh flour will be improved. The results of the sensory evaluation of the bread and cookies indicated that the bread made with samh flour upto 30% has similar characters except for the crumb color and the overall acceptability which were rated as significantly inferior. The sensory evaluation of the cookies showed that the cookies made with samh flour upto 100% were significantly superior (p<0.05) to the cookies made with 100% wheat flour (control).