Addition Of Mineral Nutrients Research Articles

Windrow Composting of a Pulp and Paper Mill Sludge: Process Performance and Assessment of Product Quality

Pulp and paper mill sludges (PMS) are a significant by-product of the paper making industry worldwide, and composting with mineral nutrients in Tasmania is viewed as the most environmentally acceptable technology to convert this material into a useful horticultural or agricultural product, thereby eliminating the need for landfilling. The objective of this study was to determine the feasibility of composting PMS in large-scale periodically turned windrows based on optimal conditions previously determined in laboratory-scale reactors. Performance of the composting process and quality of the composted PMS is reported. PMS was composted with mineral nutrients at an initial C:N:P:K ratio of 35:1:0.6:0.1 in three windrows of 25 m in length, 3 m in width and 2 m in height with weekly turning for 21 weeks, following which the trial was terminated. Temperature at the pile center remained above 50°C for the duration of the trial, with pile pH peaking at 7.46 after 11 weeks. At termination, phytotoxicity was absent and pile volume had decreased by 45 percent, partly due to a 31.6 percent increase in bulk density and a decrease in gravimetric water content from 71.4 percent before to 63.7 percent after composting. Due to the moderate level of aluminum in the PMS compost, substitution of the aluminum sulfate flocculant used in primary clarification and sludge dewatering with a nonaluminum based flocculant may be required to reduce the potential for aluminum toxicity in plants. The C:N ratio was reduced from 218:1 prior to mineral nutrient addition to 23:1 after composting with a concomitant rise in electrical conductivity from 0.59 dSm−1 to 2.78 dSm−1, possibly making the material unsuitable for direct contact with plants sensitive to moderately saline conditions. The electrical conductivity could be reduced to less than 2 dSm−1 by substituting some of the nitrogen and potassium amendments with nonsalinizing nutrient forms, thereby substantially improving the quality of the composted PMS.

Characteristics of organics removal by PACT simultaneous adsorption and biodegradation

The use of powdered activated carbon treatment (PACT), based on simultaneous adsorption and biodegradation, is effective for treating organic toxic pollutants, present in industrial wastewaters. Removal of phenol and aniline from aqueous solutions by biological treatment alone, by adsorption on powdered activated carbon (PAC) alone and by simultaneous adsorption and biodegradation were compared. In the adsorption experiments, Langmuir adsorption isotherms were obtained, from which Q o, the limiting adsorption capacities, and b, the constant related to the energy of adsorption, were determined. Q o values of phenol and aniline were found to be similar, while the energy-related constant for aniline was five times higher than for phenol. Addition of mineral nutrients, needed for the biological treatment, and inactivated microbial cells increased the limiting adsorption capacities and significantly decreased the energy related constants. In biological treatment alone, kinetic studies showed that aniline was more resistant to biodegradation than phenol. In the simultaneous adsorption and biodegradation process, the PAC presence differently affected the biooxidation of phenol and aniline. While the PAC enhanced the microbial respiration in the phenol bioreactor, it significantly reduced the microbial respiration in the aniline bioreactor. Different organic removal mechanisms are suggested in PACT for phenol and aniline, due to their different energy of adsorption. The respirometric studies are recommended as an adequate tool for prediction of toxic organics removal capabilities from industrial wastewaters by PACT.

Growth responses of an alpine grassland to elevated CO2.

Alpine plant species have been shown to exhibit a more pronounced increase in leaf photosynthesis under elevated CO2 than lowland plants. In order to test whether this higher carbon fixation efficiency will translate into increased biomass production under CO2 enrichment we exposed plots of narrow alpine grassland (Swiss Central Alps, 2470 m) to ambient (355 μl l-1) and elevated (680 μl l-1) CO2 concentration using open top chambers. Part of the plost received moderate mineral nutrient additions (40 kg ha-1 year-1 of nitrogen in a complete fertilizer mix). Under natural nutrient supply CO2 enrichment had no effect on biomass production per unit land area during any of the three seasons studied so far. Correspondingly, the dominant species Carex curvula and Leontodon helveticus as well as Trifolium alpinum did not show a growth response either at the population level or at the shoot level. However, the subdominant generalistic species Poa alpina strongly increased shoot growth (+47%). Annual root production (in ingrowth cores) was significantly enhanced in C. curvula in the 2nd and 3rd year of investigation (+43%) but was not altered in the bulk samples for all species. Fertilizer addition generally stimulated above-ground (+48%) and below-ground (+26%) biomass production right from the beginning. Annual variations in weather conditions during summer also strongly influenced above-ground biomass production (19-27% more biomass in warm seasons compared to cool seasons). However, neither nutrient availability nor climate had a significant effect on the CO2 response of the plants. Our results do not support the hypothesis that alpine plants, due to their higher carbon uptake efficiency, will increase biomass production under future atmospheric CO2 enrichment, at least not in such late successional communities. However, as indicated by the response of P. alpina, species-specific responses occur which may lead to altered community structure and perhaps ecosystem functioning in the long-term. Our findings further suggest that possible climatic changes are likely to have a greater impact on plant growth in alpine environments than the direct stimulation of photosynthesis by CO2. Counter-intuitively, our results suggest that even under moderate climate warming or enhanced atmospheric nitrogen deposition positive biomass responses to CO2 enrichment of the currently dominating species are unlikely.

Changes in the composition of globoids in castor bean cotyledons and endosperm during early seedling growth with and without complete mineral nutrients

AbstractThe endosperm and cotyledon tissues of Ricinus communis seeds and young seedlings were examined for changes in the mineral nutrient composition of globoids during early seedling growth. The effect on globoid composition of providing mineral nutrients to the developing seedling was also investigated. Globoids in endosperm and cotyledon tissues of castor bean seeds contained P, Mg and K, as well as trace amounts of Ca, Fe and Zn. Irrespective of the addition of mineral nutrients, K content in globoids of endosperm and cotyledon tissues declined significantly during initial seedling growth. During early seedling growth, amounts of Fe, Zn and Ca increased in cotyledon globoids. Ca contents of globoids of endosperm tissues also increased. The changes in Fe, Zn and Ca globoid contents were not influenced by providing mineral nutrients to growing castor bean seedlings.

Effects of fire season and soil fertility on clonal growth in a pyrophilic forb, Pityopsis graminifolia (Asteraceae)

We experimentally manipulated fire season in a longleaf pine sandhill community in north Florida in 1990 and 1992. We determined the size and demography of shoots, rhizomes, and clones of Pityopsis graminifolia from late 1990 to early 1993. In addition, we examined shoot responses to seasonal variation in canopy/litter removal and soil fertility in 1992. May fires caused a higher short‐term rate of increase in shoot density than did either January fires or August fires. The combination of canopy/litter removal and mineral nutrient addition as part of the clipping experiment revealed a similar effect on shoot density in May. Fire season influenced clone structure. May fires resulted in greater numbers of shoots/clone than did January or August fires. January‐burned plots had clones and rhizomes that contained larger (but fewer) shoots than did May‐burned or August‐burned plots. We suggest that such variation in clone structure may indicate a greater capacity of clones to grow laterally following May fires than following either January or August fires. This capacity is positively associated with the likelihood that longleaf pine savannas will be burned by lightning fires at different times during the year.

Effects of Fire Season and Soil Fertility on Clonal Growth in a Pyrophilic Forb, Pityopsis graminifolia (Asteraceae)

We experimentally manipulated fire season in a longleaf pine sandhill community in north Florida in 1990 and 1992. We determined the size and demography of shoots, rhizomes, and clones of Pityopsis graminifolia from late 1990 to early 1993. In addition, we examined shoot responses to seasonal variation in canopy/litter removal and soil fertility in 1992. May fires caused a higher short-term rate of increase in shoot density than did either January fires or August fires. The combination of canopy/litter removal and mineral nutrient addition as part of the clipping experiment revealed a similar effect on shoot density in May. Fire season influenced clone structure. May fires resulted in greater numbers of shoots/clone than did January or August fires. January-burned plots had clones and rhizomes that contained larger (but fewer) shoots than did May-burned or August-burned plots. We suggest that such variation in clone structure may indicate a greater capacity of clones to grow laterally following May fires than following either January or August fires. This capacity is positively associated with the likelihood that longleaf pine savannas will be burned by lightning fires at different times during the year.

Growth of 24 full‐sib families ofPinus sylvestrisL. At six relative nutrient addition rates

Path analysis was used to study shoot elongation of Scots pine seedlings grown under six relative mineral nutrient addition rates (Ra). The shoot length is composed of two growth components: number...

Influence of mineral nutrients on high performance during anaerobic treatment of distillery wastewater from barley- shochu making

The influence of the mineral nutrients Ni 2+ and Co 2+ was studied in order to improve the reaction rate in the anaerobic treatment of distillery wastewater. Wastewater from barley- shochu making, supplemented with mineral nutrients, was treated by a thermophilic single-phase methane fermentation process using an anaerobic fluidized-bed reactor. A maximum TOC volumetric loading rate of 42 g/ l·d, with a TOC removal efficiency of 78%, was achieved. This rate was 4-fold higher than that without the addition of the mineral nutrients. The gas yield was 1.7 l/g TOC consumed, which corresponds to 90% of the theoretical yield. In mesophilic single-phase methane fermentation, the addition of mineral nutrients also accelerated the reaction rate 5-fold compared to that without the addition of mineral nutrients.

Relationship of forest damage to air pollution in the nordic countries

In the Nordic countries, the bedrock is largely slowly weathered gneiss and granite with low amounts of nutrients. The soils are easily disturbed by acid rain; very low pH values and base saturation is found in the exposed areas of south Norway and southwest Sweden. Events with high levels of sulphur dioxide and/or other pollutants transported from Central Europe are common. Ozone continuously reaches concentration levels that damage vegetation during the summer. The total sulphur and nitrogen input to forests exceeds the tolerance limits of nature in the mentioned areas, and causes soil acidification and nutrient imbalance in the soil and in the forest trees. Low summer temperatures during recent years have affected large areas of the northern parts of the Nordic countries. The negative effects of air pollutants have been amplified by some dry years, affecting mainly the southern parts of the Nordic countries. In Sweden, 5000 out of 16 000 acidified lakes are limed today. Liming and mineral nutrient addition in the forests are also discussed as countermeasures.

Possible reasons for the failure of natural microbial community to degrade low concentration of 2,4-dichlorophenol.

The rapid microbial degradation of 2, 4-dichlorophenol (DCP) at 1.0μg DCP-C/ml in a groundwater was observed when the density of responsible degraders, estimated by the most probable number (MPN) method, had increased to 105 cells/ml. However, no degradation of 0.1 or 0.03μg DCP-C/ml was observed even when the density of degraders had increased to 104-105 cells/ml. Rapid degradation of 0.1μg DCP-C/ml occured within a day in the qroundwater in which 1.0μg DCP-C/ml was degraded beforehand, but not in the groundwater which had been precultured with 0.1μg DCP-C/ml. Addition of mineral nutrients enhanced the degradation of 0.1μg DCP-C/ml, but not the growth of degraders. These results suggest that in the groundwater the failure of DCP degradation at low concentration may be attributable to the failure of degraders to express their DCP-degrading activity, such as induction of responsible enzyme(s), and not to the failure to grow or to increase their density.

Composition and activity of the microbial population in an acidic upland soil and effects of liming

The microbial population and microbial activity were examined in the strongly acidic organic horizon of a brown podzolic soil. The short- and long-term effects of liming the soil on these properties were also examined. Liming increased the bacterial population ca 20-fold in 32 days but this extreme effect did not persist. The increase in the bacterial population was mainly in acid intolerant species. None of the two methods of assessment used showed any significant change in the fungal population either in the short- or long-term after liming. Liming caused a rapid and substantial increase in both soil respiration and net nitrogen mineralized despite a rather high C-to-N ratio of soil organic matter. Comparison between the native and long-term limed soils in gross and net N mineralized together with the respiration response in the native soil to glucose and mineral nutrient additions suggested that the activity of the microbial population in the native soil was not limited by available N. Furthermore herbage yields and nutrient offtake suggested that herbage yields on the native soil were not restricted by available N. Nitrate was produced in the aerobically incubated native soil but probably not all by autotrophic nitrifiers.

EFFECTS OF APEX REMOVAL AND NUTRIENT SUPPLEMENTATION ON BRANCHING AND SEED PRODUCTION IN THLASPI ARVENSE (BRASSICACEAE).

The shoot apex of a plant may be damaged by herbivory, weather conditions, or other factors, leading to growth of some axillary buds into branches. This alteration of branching pattern can affect the location and extent of seed production. I examined the effects of removal of the shoot apex and of mineral nutrient addition on branching and seed production in Thlaspi arvense. Individual plants received no, early, or late apex removal and no, early, or late nutrient addition in a two-way factorial experiment. Apex removal led to greater production of secondary branches. Total seed weight per plant was higher for early- than late-removal plants under all nutrient treatments, but intact controls produced the highest total weight of seeds in two of three nutrient treatments, because their seeds were heavier. Addition of nutrients increased the numbers of secondary branches, fruits, and seeds, and the average and total weight of seeds produced. Apex removal resulted in increased seed production only when it occurred early and when nutrients were added at the same time. Resource availability and plant phenology can be influential in determining the effects of apical damage on seed production, and their effects in combination may differ from their individual effects.

Carbon and Mineral Element Accumulation and Allocation in Two Annual Plant Species in Response to Timing of Nutrient Addition

(1) The effects of the timing of a large 'pulse' addition of mineral nutrients on accumulation and allocation of C, N, P, K and Ca, and on seed production and element status, were examined in the annual plants Abutilon theophrasti and Datura stramonium. (2) Nutrient addition increased total plant weight and element content, but the increase occurred over a period of several weeks rather than within the week after the addition. (3) The various mineral elements were allocated independently of carbon and of each other in both species. A. theophrasti started reproduction later than did D. stramonium and had lower proportional allocations of weight, N and P to reproduction at the final harvest. (4) Although nutrient pulse addition produced a temporary increase in proportional allocation of weight, N and P to leaves shortly after the addition, pulse timing had little effect on final proportional allocations. Plant age had a greater effect on allocation patterns than did the nutrient treatments. (5) Differences in seed production observed among nutrient treatments appeared to result primarily from differences in total accumulation of carbon and other elements and hence total plant growth, rather than from differences in proportional allocations. (6) Element concentrations of seeds and capsules, and mineral element contents per seed, did not differ among the treatments, and variation in mean seed weight among treatments was relatively small.

Induction of Sensitivity to Gibberellic Acid in Developing Wheat Caryopses: Effect of Sugars in the Culture Medium

The influence of sugars in culture media on the development of the ability of the aleurone layer to respond to gibberellic acid was investigated by culturing detached wheat ears for 6 days and then measuring the hormone-induced α-amylase activity in incubates of endosperm halves derived from the cultured ears. Some response to gibberellic acid was found after ears had been cultured on water, or on solutions of either sorbitol or mannitol. Addition of mineral nutrients plus glutamine to these culture media reduced the response. Likewise, the addition of sucrose, glucose and/or fructose or galactose reduced the response, and a complete culture medium abolished the response, giving endosperm halves which were similar to those from ears retained on the plant. Supplying mannose to the culture medium yielded endosperm halves as responsive to gibberellic acid as those from fully air-dried caryopses. The separate effects of mannose and sucrose were concentration dependent in the range 1-10 mM. Adding mannose and/or glucose to GA3-containing incubates of endosperm halves did not alter the intensity of α-amylase activity in these incubates. The results were interpreted as an effect of the sugars on the metabolic status of the inflorescence.

Fertilization Response of Early and Late Successional Species: Acacia smallii and Celtis laevigata

The sequential dominance of Acacia smallii and Celtis laevigata during secondary succession may be explained in part by examining the nutrient requirements of these two species. Acacia smallii has a low soil N requirement, while C. laevigata has a high soil N requirement. Growth of A. smallii and C. laevigata seedlings on amended soil was determined in a greenhouse experiment by measuring the increase in number of leaves, leaf length, plant height, and biomass. Using a factorial design with N and a complete nutrient supplement minus N, we determined that A. smallii biomass was stimulated 1.35-fold by the addition of mineral nutrients minus N, but it was not stimulated by N. Celtis laevigata biomass increased 5.6-fold with the addition of NH4NO3 but not with the addition of other nutrients.

The Influence of Mineral Nutrients on the Growth of Ammophila Arenaria

Differences in vigour of marram grass, Ammophila arenaria (L.) Link, growing in different parts of sand-dune systems, are well known and have been frequently recorded (Carey & Oliver 1918; Tansley 1949; Salisbury 1952; Willis, Folkes, Hope-Simpson & Yemm 1959b; and others). Characteristically marram is vigorous in the fore dunes, especially in areas receiving abundant supplies of blown sand, but grows poorly, often ultimately degenerating to the point of dying, in the inland parts of dune systems where there is much less sand movement and where the vegetation cover may be considerable. The chief suggestions which have been made regarding the basis of these differences in vigour involve aeration, water regime, nutrient regime, organic matter content of the sand, the presence of toxic substances and competition. The possible importance of the effects of the levels of essential mineral nutrients was explored in the investigations reported here, which were carried out in conjunction with studies of the mineral nutrient status of the dune soils of Braunton Burrows, north Devon (Willis & Yemm 1961), and of the influence of the addition of mineral nutrients to various types of vegetation on the dunes (Willis 1963). Results bearing on the problem of the vigour of marram were obtained from two approaches. Mineral nutrients were added at various intervals to an area of pure A. arenaria growing on the slope of a high dune at Braunton Burrows and the effect of this treatment was assessed by measuring the marram periodically and finally cutting and weighing it. The general procedure adopted here was that described by Willis (1963). In a second approach, marram seedlings were transplanted into pots containing sand from Braunton Burrows and grown under glasshouse conditions. They were subjected to a number of mineral nutrient regimes over a period of 3 years and measurements of growth were made on a number of occasions. In this experiment not only was the effect of a range of mineral nutrient treatments studied, but also the effect of the addition of sand to the pots when the marram had been growing for about 15 months.

Braunton Burrows: The Effects on the Vegetation of the Addition of Mineral Nutrients to the Dune Soils

Braunton Burrows: The Effects on the Vegetation of the Addition of Mineral Nutrients to the Dune Soils