Calcareous Loam Research Articles

Changes in some chemical properties of arid soils as affected by synthetic polymers

Four soil conditioners, Broadleaf P4, Agrihope, Aquasorb, and Hydrogel, were used in a laboratory study to investigate the effect of these polymers on chemical properties of two calcareous sand and loam soils. Four concentrations of each polymer used were 0.0%, 0.2%, 0.4%, and 0.6% (w/w). All treatments were irrigated weekly to 60% water holding capacity for a total of 16 wetting and drying cycles. The addition of conditioners induced a substantial change in the selected soil chemical properties. For both soils, pH and EC values increased significantly with corresponding increase in concentrations of all conditioners. The extractable nutrients (Zn, Cu, Mn, Fe, P, and K) fluctuated irregularly with the four concentrations of each conditioner. In sandy soil the application of all conditioners significantly increased extractable P, whereas extractable Zn remained unaffected. Extractable Mn significantly decreased with Broadleaf and Aquasorb application but increased with Agrihope. Extractable Fe increased wi...

Cadmium analysis in soil by microwave acid digestion and graphite furnace atomic absorption spectrometry.

The need to determine micronutrients and toxic elements in soils has grown in recent years and cadmium is of special interest. A method has been developed for the determination of cadmium in soils based on a prior acid digestion of the samples with nitric acid in closed Teflon vessels, into a microwave over. The cadmium determination was carried out by graphite furnace atomic absorption spectrometry (GFAAS) with L'vov platform. Optimum operating conditions, analyte modifiers and matrix interferences have been investigated. The best matrix modifier was found to be ammonium dihydrogen phosphate. The interferences are greatly reduced under these operating conditions and calibration can be performed with simple aqueous solutions of the metal standard. The method is rapid and provides accurate and precise results that agree with certified values for two reference materials: BCR 141 (calcareous loam soil) and BCR 277 (estuarine sediment).

Sewage sludge as a potential source of lead in liver, kidney and muscle tissues of growing lambs

Addition of sewage sludge to grassland may be reflected in ingestion of lead by animals with implications for the human food chain. The research reported here was part of a series of experiments conducted to investigate the possible risk to the health of livestock and humans associated with the use of sewage sludge in agriculture. The transfer of several elements to the body tissues of lambs was examined, including that of cadmium, copper, zinc and lead. The results for lead are reported in this paper.Weaned Kent lambs (6/treatment, 20 to 45 kg liveweight) were given dried grass ad libitum (Trial 1, indoor feeding) either as the sole feed (C) or with 100 g/kg DM of one of two soils (CM, sandy -pH 6.18; or RM, a calcareous loam - pH 7.55) which had been amended historically with sewage sludge and which contained 102 (CM) and 130 (RM) mg Pb/kg DM.

Sewage sludge as a potential source of lead in liver, kidney and muscle tissues of growing lambs

Addition of sewage sludge to grassland may be reflected in ingestion of lead by animals with implications for the human food chain. The research reported here was part of a series of experiments conducted to investigate the possible risk to the health of livestock and humans associated with the use of sewage sludge in agriculture. The transfer of several elements to the body tissues of lambs was examined, including that of cadmium, copper, zinc and lead. The results for lead are reported in this paper.Weaned Kent lambs (6/treatment, 20 to 45 kg liveweight) were given dried grass ad libitum (Trial 1, indoor feeding) either as the sole feed (C) or with 100 g/kg DM of one of two soils (CM, sandy -pH 6.18; or RM, a calcareous loam - pH 7.55) which had been amended historically with sewage sludge and which contained 102 (CM) and 130 (RM) mg Pb/kg DM.

Factors affecting nitrate leaching from a calcareous loam in East Anglia

SUMMARYThe effects of overwinter cover cropping, delayed ploughing and method of straw disposal on the quantities of nitrate leached (averaged over three winters during 1989–93) from a chalk loam in Eastern England were examined. The recovery of ‘retained’ nitrogen (retained through cover crop uptake, delayed ploughing and immobilization by straw) in a following spring crop was also assessed. In the first two winters, the rye cover crop decreased nitrate leaching by > 90% (28 kg N/ha per year), as compared with bare fallow treatments. In 1992/93 this decrease was only 23% (10 kg/ha), due to the early onset of drainage before cover was well established. Delayed ploughing on bare treatments, to decrease autumn N mineralization and subsequent nitrate leaching, was ineffectual in 1989/90 but had substantial effects in 1990/91 and 1992/93; N mineralization, inferred from soil mineral nitrogen content, and nitrate leaching were decreased by 31 and 35% in 1990/91 and by 36 and 61% in 1992/93, respectively. Nitrate leaching (averaged over three winters) was unaffected by straw incorporation. There was no evidence of recovery of cover crop N in the spring sown test crops (barley or sugarbeet). In the low soil N input situation encountered in this experiment, it was unnecessary to sow cover crops before early September in years of average or below average rainfall to ensure that the average soil solution concentrations remained below the EU drinking water limit of 11 mg NO3-N/1. However, in wetter seasons substantial N leaching occurred before cover had taken up much N. In 1992/93 N retained against leaching by a rye cover crop in previous years was apparently being remobilized and lost through leaching, although if cover was grown again there was less leaching than from bare land. In the future, an increase in the extent of cover cropping might increase transpiration rates and therefore lead to a decrease in aquifer recharge.

Separation and determination of gold from iron rich matrices by an off/on-line preconcentration system coupled to ICP-AES

A preconcentration/separation method has been developed for the off/on-line determination by ICP-AES of gold in complex matrices, containing iron and manganese which cause severe spectral interferences on the two most sensitive Au-lines. The available automated preconcentration apparatus was modified using as absorbent the highly selective, for precious metals, chelating anion exchanger SRAFION NMRR. From the elution of this resin with 5% thiourea a nearly quantitative recovery of gold and its separation from iron, existing in percent range in the matrix, and from manganese was obtained. The validity of the developed method was tested by the determination of gold in standard reference materials from BCR, such as sewage sludge of domestic and mainly industrial origin and in a calcareous loam soil. The preconcentration procedure was synchronized with the ICP operating parameters in order to get an optimised on-line coupling of these two systems. The described process has been successfully applied to the determination of low gold contents in dissolved iron rich sediments using for the gold prospection.

The effect of rock phosphate-enriched compost on the yield and phosphorus nutrition of rye grass

AbstractWe evaluated the effect of compost enriched with rock phosphate on the yield and phosphate nutrition of rye grass in a calcareous clay loam soil. Enriched compost was prepared by composting either Mussoorie rock phosphate (MP) or Hyper rock phosphate (HP) separately with wheat straw for up to 120 days. A significant amount of insoluble P was solubilized from both kinds of rock phosphates and converted to water soluble, organic, and formic acid soluble P fractions during composting. MP-enriched compost (MPEC) and HP-enriched compost (HPEC) contain 0.30% and 0.34% water soluble P205, 1.94% and 1.42% organic P2O5 2.82% and 3.28% formic acid soluble P2O5, and 1.76% and 1.18% insoluble P2O5, respectively. In a greenhouse study, the yield of ryegrass (three cuttings) with both enriched composts was not significantly different from that of single superphosphate fertilizer (SSP). Phosphorus fractions of soil before sowing and after harvesting the rye grass showed that fixation of P with native soil calcium was much higher with SSP than with enriched composts. No significant differences were observed between MRP and HRP.

Determination of cadmium, copper and lead in environmental samples. An evaluation of flow injection on-line sorbent extraction for flame atomic absorption spectrometry

A flow injection on-line sorbent extraction system was studied in conjunction with flame atomic absorption spectrometry to determine cadmium, copper and lead in digest solutions of solid environmental samples using octadecyl functional groups (C 18) bonded silica gel as sorbent with diethylammonium- N,N-diethyldithiocarbamate (DDDC) or ammonium diethyldithiophosphate (DDPA) as complexing agent and methanol as eluent. Using DDDC as complexing agent, citric acid was used as masking agent for iron and manganese. The complexing agent DDPA selectively extracts cadmium, copper and lead at pH values 1 to 3. Using DDPA as complexing agent with citric acid at pH 1.0, the results of the analysis of five environmental standard reference materials, including coal fly ash (CRM 038), calcareous loam soil (CRM 141), lake sediment (CRM 280), river sediment (CRM 320) and estuarine sediment (CRM 277) after digestion were in good agreement with the certified values except cadmium in the river sediment with a very high iron content. With a 20-s sample loading at 8.7 ml min −1, detection limits (3σ) were 0.8, 1.4 and 10.0 μg l −1 respectively for cadmium, copper and lead.

Using the Creams Pesticides Transfer Sub-Model at a Rainfall Simulation Scale

The pesticide sub-model of CREAMS was tested to describe pesticides transfer into runoff generated by a rainfall simulation. Adsorption coefficient, Kd, was found to be a sensitive parameter of the model. So, we developed an experimental method in order to measure Kd in a dynamic way. We studied four pesticides (atrazine, simazine, lindane, methidathion) and three soils (loam sand, sand loam, calcareous silt loam). The values of Kd obtained were compared to the values measured on the soils by the standardized method of batches and to the values of the literature. Mean Kd measured in the runoff of a rainfall simulation were considerably greater, especially for low suspended particles loads. We ran the model with these different data for Kd and we found that predictions were more accurate with Kd obtained by rainfall simulation particularly for lindane and simazine. We improved the modelisation for atrazine and methidathion. Nevertheless, the relative error between observed and predicted concentrations was not the same according to the pesticide, which made prediction of risk dependent on pesticides classes of behaviour.

Seasonal sucrose, drymatter, and cation concentrations of sugarbeet as influenced by variety and N‐fertilization

Abstract This study evaluated the effect of variety and nitrogen (N) fertilization on sucrose, dry‐matter, and cation concentrations in sugarbeet (Beta vulgaris L.) root tissue. A field experiment was conducted on a non‐saline, calcareous Nunn clay loam soil (Aridic argiustoll) using a factorial experimental design with three N‐rates, two varieties, and four replications. Beets were harvested nine times during the growing season. The first and final harvests were on June 25 and October 11, respectively. In addition to the above measurements, purity and extractable sucrose also were measured at the final harvest. Dry‐matter content, sucrose, sums of monovalent and divalent cations, and the monovalent:divalent cation ratios all were influenced significantly by variety, N‐fertilization, and date of harvest. Sucrose concentration was negatively correlated to the sum of monovalent and divalent cations. Root drymatter content was negatively correlated to the monovalent:divalent cation ratio. A relationship of c...

Spatial variability of selected carbon, nitrogen, and phosphorus parameters on acid and calcareous rangeland soils

Abstract The magnitude of C, N, and P seasonal or long‐term variability in rangelands is difficult to assess because of intrinsic soil heterogeneity even in seemingly uniform areas. A need exists, therefore, to determine the minimum number of samples necessary so significant changes in C, N and P can be assessed where minimal confounding from soil types and vegetation exist. To achieve this end, laboratory and field studies of selected C, N, and P parameters were conducted to compare variability among six transect lines, radiating from a central point. Samples were taken along each transect line every 3 m to a distance of 15 m. Parameters measured were: total organic C (OC), total Kjeldahl N (TKN), NH4‐N, NO3‐N, NaHCO3‐extractable inorganic P (NaHP), and total organic P (TPo). Two rangeland soils, a moderately acid Ascalon sandy loam, and a calcareous Haverson loam, were sampled at two depths to assess spatial differences. Results indicated that under the experimental conditions, OC, TKN and TPo would req...

Interactions encountered when supplying iron, phosphorus and nitrogen fertilizer to two cultivars of soybeans

Abstract An Fe‐efficient and an Fe‐inefficient cultivar of soybean were grown in calcareous Hacienda loam soil with FeEDDHA, P and N fertilizers in factorial combination. With the Fe‐efficient cultivar (Hawkeye), there was response to Fe alone (40 percent) and very small responses to P alone (5 percent) and N alone (13 percent). When N and P were combined there was antagonism. The Fe with P and Fe with N both gave sequentially additive interactions or very near. When all three inputs were combined the responses to Fe, P and N, respectively, were 80, 35, and 44 percent, and the interaction was synergistic. Each nutrient was a Liebig‐type limiting factor. With T‐203 soybean, FeEDDHA gave no response when used alone, and N and P singly and together were very antagonistic. When all three nutrients were supplied simultaneously, the interaction was synergistic with responses to Fe, P and N, respectively, 569, 471, and 116 percent. Even after Fe had been supplied, the N and P were Liebig‐type limiting factors. Y...

Biomass production and transpiration efficiencies of eucalypts in the Negev Desert

The above-ground productivity and summer water-use patterns of five species of Western- and central-Australian eucalypts were examined in irrigated plantations in the northern Negev Desert of Israel. Biomass production was evaluated by whole-tree harvesting. Leaf transpiration rates were measured using a steady-state porometer. Eucalyptus salubris was considered the most efficient in its water use because it had the highest productivity (1169 kg ha −1 year −1) and the lowest transpiration rates. Eucalyptus torquata was only slightly less efficient than E. salubris. Eucalyptus woodwardii was comparable in terms of productivity but it transpired at much higher rates. Eucalyptus socialis and E. grossa were the least efficient in their water use because of their significantly lower productivity (<660 kg ha −1 year −1. Of these five species, E. salubris and E. torquata appear to have the most potential for afforestation under conditions comparable to the northern Negev, where the potential evaporation rate is 2140 mm year −1, the soil is a calcareous loam, the mean annual rainfall is about 100 mm, and trickle irrigation provides a supplement of 150 mm year −1.

Mobilization and fractionation of137Cs in calcareous soils

Mobility of137Cs was investigated in columns of calcareous loam and clay soils leached under river water, NH4OAc, KCl, CaCl2, and EDTA. Fractionation of Cs into ten sequential fractions was accomplished in the leached soils as well as in soil samples received carrier-free137Cs and incubated for 60 d. At the end of 90 d of leaching with river water and CaCl2, the bulk of Cs applied (>97%) was found to remain in the upper 1 cm of soil columns. On the other hand, the reduction in Cs concentration was approximately 30% with NH4OAc, 18% with KCl, and 10 to 25% with EDTA. The major soil constituents appeared to be responsible for retaining Cs were clay, silt, and Fe oxides. The leaching consistently increased the magnitude of fractions bound to clay minerals and in most cases decreased the fractions of water soluble, exchangeable, carbonate, and organic matter.

Patterns of Community Structure and Morphology of Bryophytes and Lichens Relative to Edaphic Gradients in the Subarctic Forest-Tundra of Northwestern Canada

Patterns of Community Structure and Morphology of Bryophytes and Lichens Relative to Edaphic Gradients in the Subarctic Forest-Tundra of Northwestern Canada

Fertiliser effectiveness of acid extracted phosphorus from low grade phosphate rock

Low grade phosphate rock (PR), containing high amounts of oxides of iron and aluminium is neither suitable for fertiliser production nor useful for direct application to annual crops. The fertiliser effectiveness of P extracted by H2SO4 from a low-grade phosphate rock, PR (Christmas Island C-grade PR) was evaluated for wheat (Triticum aestivum L.) on a calcareous loam (pH 8.4) and a non-calcareous loam (pH 6.9) in field and glasshouse experiments. Superphosphate was used to compare the performance of the acid extracts of PR. In the non-calcareous loam soil, crop establishment and yield were significantly reduced by the acid extracts of PR due to increased acidity. In the calcareous soil, however, the acid extracts of PR performed as well as superphosphate; similar or even higher crop yields were obtained with the former, especially when applied near the seed. The acid extracts of low-grade PR may, therefore, have a role in calcareous soils, where the extract can be applied directly or added in the irrigation waters to supply P to crops.

Variation amongTrifoliumspecies for resistance to iron‐deficiency chlorosis

Abstract Little information is available regarding the amount of genetic variation among and within Trifolium species for resistance to iron (Fe)‐deficiency chlorosis. A calcareous Parrita sandy clay loam soil (clayey, mixed, hyperthermic, shallow Petrocalcic Paleustoll) that had a history of expression of Fe‐deficiency chlorosis problems in forage sorghum (Sorghum bicolor L. (Moench.)) was used to conduct field studies in 1985–86 and 1986–87. Cultivars of seven Trifolium spp.: arrowleaf (T. vesiculosum Savi.), berseem (T. alexandrinum L.), crimson (T. incarnatum L.), red (T. pratense L.), rose (T. hirtum All.), and subterranean (T. subterraneum L. and T. brachycalycinum Katzn. and Morley) clovers were compared for differences in dry matter production and expression of chlorosis symptoms. Cultivars could be ranked for their adaptability to calcareous soil conditions: ‘Bigbee’ berseem = ‘Kenstar’ red = ‘Kondinin’ rose = ‘Clare’ subterranean > ‘Dixie’ crimson >> ‘Mt. Barker’ subterranean > ‘Yuchi’ and ‘Meec...

Revaluation of the internal standard method coupled with the standard addition method applied to soil samples by means of photon activation

In order to achieve the highly accurate and precise multielement determination in environmental materials, the usefulness of the comparative standard provided by the processing method proposed previously for soil samples has been re-examined using calcareous loam soil, light sandy soil and river sediment as unknown samples. As a result, it was also demonstrated that concentrations of 15 trace elements in each sample can be determined effectively and reasonably.

Application of Urea Phosphate and Urea Sulfate to Drip-irrigated Tomatoes Grown in Calcareous Soil1

The potential benefit of acid applied through drip irrigation on soil nutrient availability, plant nutrition, and yield was studied. Tomatoes (Lycopersicon esculentum Mill., cv. Better Boy) were grown in a P-deficient calcareous loam soil in 114-L plastic-lined cans. Phosphorus was added weekly through drip irrigation as urea phosphate (UP) (17-19-0) at four concentrations (0, 20, 40, 80 kg P ha−1). Two other treatments entailed 40 kg P ha−1 soil-banded triple superphosphate (TSP) (0-20-0) with or without the addition of drip-applied urea sulfate (US) (15-0-0-16). Urea sulfate was added at the rate equivalent to the titratable acidity of the 40 kg UP-P ha−1 treatment. Urea was added to all treatments to provide the equivalent of 100 kg N ha−1. The plants were grown for 73 d after transplanting prior to harvesting, weighing, and analysis. Soil samples were taken in 5-cm depth increments at 0-, 10-, and 20-cm distances from the emitter and analyzed for pH, P, Fe, Mn, and Zn. Yields of fruit and vegetative matter were higher in the 20 kg UP-P ha−1 treatment than in any other treatment. Phosphorus moved in the soil to a depth of 30 cm at the 80 kg UP-P ha−1 application rate. Leaf Zn concentration decreased with increasing rates of P fertilization. Application of acid solubilized native soil P, Fe, and Mn, resulting in highest tissue concentrations of Fe and Mn in the plants receiving US. Urea sulfate was more effective in soil acidification and Fe and Mn solubilization than the equivalent titratable acidity derived from UP. Urea sulfate may be beneficial where Fe and Mn deficiencies occur. Urea phosphate appears to be an effective P fertilizer for application through drip irrigation systems in field soil.

Effects of bicarbonate, phosphorus, iron EDDHA, and nitrogen sources on soybeans grown in calcareous soil

Abstract Hawkeye soybeans (Glycine max L.), an iron‐efficient cultivar when grown in calcareous Hacienda loam soil low in P and available Fe, did not respond to P, FeEDDHA, NH4+‐N or NO‐ 3‐N when applied singly nor to Fe + P together; but did give yield response for N + P + Fe applied together. Addition of HCO3 ‐ with N + P + Fe decreased yields by about 10% and decreased Fe in shoots also by 10%. The NH4+ source of N gave 12% higher leaf yield without HCO3 ‐ and 11% higher with HCO3 ‐ than did nitrate N. Bicarbonate alone caused severe damage to the Hawkeye soybeans, while P alone had little effect. In contrast, P was very damaging with less effect from HCO3 ‐ with iron‐inefficient PI‐54619–5–1 soybeans from a companion study. Addition of Fe decreased Zn and Mn concentrations in leaves, while addition of both Fe and P decreased Zn concentration even more. Bicarbonate contributed additionally to low Zn in leaves with treatments of Fe and Fe + P. These Fe‐efficient Hawk‐eye soybeans were less impaired by N...