Effect Of Soil Nutrient Status Research Articles

Study on the Effects of Salt Tolerance Type, Soil Salinity and Soil Characteristics on the Element Composition of Chenopodiaceae Halophytes.

With the continuous increase in saline–alkali land, sustainable development of the global environment and ecology have been seriously affected. This study compared the absorption and accumulation patterns of 11 elements in different parts (roots, stems and leaves) of different leaf Na regulation strategies of the pioneer plant Chenopodiaceae in saline–alkali land and evaluated the effects of soil nutrient status and soil salinity on the distribution of plant elements. The results showed that the changes in the content of Ca, Mg and Na in plants are affected by the salt-tolerant type and on different parts. Soil salinity had no significant effect on element concentrations in different parts of plants. The Pearson correlation coefficient showed that the correlation between plants and soil elements was different, and different parts of plants had the characteristics of selective absorption of soil elements. The salt tolerance type and soil mineral element concentrations explained most of the variation observed in element concentrations in Chenopodiaceae plants; the soil salinity property played only a minor role. It was concluded that the genetic factors are the prerequisite in the composition pattern of leaf elements in Chenopodiaceae, and soil factors are the key to determining element accumulation. These conclusions provide an effective reference for evaluating plant breeding and its response to environmental change in saline–alkali arid areas in Hulunbuir grassland and other parts of the world.

Comparative Effects of Soil Nutrient Status and Texture on Mycorrhiza – Legume Base Cropping System in Two Soil Types of Nigeria

Soil nutrients and texture determine the rate of response of crops to mycorrhizal colonization. A two-year field experiment was conducted to compare the effects of mycorrhiza – legume base cropping systems at Ekpoma and Uzeba, both in Edo State, Nigeria. The experiment was a factorial, fitted into a RCBD with three replicates. The treatments consist of two levels of mycorrhiza and three planting systems. The descriptive statistics were used to analyse the data, and the Duncan Multiple Range Test was used to separate means (p<0.05). Ekpoma soil is moderately suitable while Uzeba soils are low in nutrient with loamy sand and sand texture respectively. The interaction of the mycorrhiza with pigeon pea significantly (p<0.05) increased the soil nutrient and nitrogen fixation in Ekpoma compared to the Uzeba location. The growth and yield of maize in Ekpoma were significantly (p<0.05) higher compared to that of Uzeba with or without mycorrhiza inoculation, with an average yield of 2.24 t ha-1 in Ekpoma and 1.51 t ha-1 in Uzeba. The inoculation of Glomus clarum increased the grain yield of pigeon pea by 48 % and 37 % compared to non-mycorrhizal pigeon pea for both sole and intercrop in both locations. The residual effect of Glomus clarum and pigeon pea on maize yield was 53% higher in Ekpoma than found in Uzeba. The loamy sand texture of Ekpoma soil enhanced the efficiency of mycorrhiza utilisation compared to the sandy texture of Uzeba.

Effect of Soil Nutrient Status on Yield and Quality of Sweet Orange (Citrus sinensis (L.) Osbeck) in YSR District of Andhra Pradesh

Effect of Soil Nutrient Status on Yield and Quality of Sweet Orange (Citrus sinensis (L.) Osbeck) in YSR District of Andhra Pradesh

Responses of Narrowleaf Cattail (Typha angustifolia) to Combinations of Salinity and Nutrient Additions: Implications for Coastal Marsh Restoration

Narrowleaf cattail ( Typha angustifolia ) is an exotic, invasive species in North America that has become abundant in many tidally-restricted salt marshes. Restoration of tidal flow to these wetlands results in elevated salinities that should favor the establishment of native salt marsh halophytes while reducing the abundance of narrowleaf cattail. However, there is some uncertainty about the salinity tolerance of narrowleaf cattail, which makes it difficult to predict vegetation trends and to interpret the actual results of restoration. Moreover, the effect of soil nutrient status on salinity tolerance of this species is virtually unknown, although many restoration projects occur in heavily urbanized settings with substantial allochthonous nutrient inputs. In this study, a salinity and nutrient addition experiment was conducted in a greenhouse to determine the effect of mineral nutrition on salinity responses in narrowleaf cattail. Within high salinity (~ 32 ppt) treatments, nutrients enhanced final biomass. Within the intermediate salinity (~ 17 ppt) treatments, nutrients significantly increased the number of leaves per shoot, sum of all leaf lengths, and final biomass. Under low salinity (~ 6 ppt) conditions, nutrient addition increased the mean height of the tallest shoot, mean height of all leaves, sum of all leaf lengths, and final biomass. The salinity responses and observed reductions in salinity-induced physiological stress by nutrient addition provide some context for forecasting and analyzing vegetation change in response to tidal restoration.

Nutrient management for jute-rice cropping system using soil test target yield equation

A field experiment was conducted during the year 2011-13 to study the nutrient management based on soil test to achieve the target yield of jute and rice and their effect of soil nutrient status for jute-rice cropping system. The target yield of jute fibre (3.5 t/ha) with -6% deviation and target yield of rice (5.5 t/ha) were achieved with application of 100% NPK based on ST-TY based along with 5 t/ha Farm Yard Manure (FYM). The highest system productivity (11.7 t/ha) and benefit-cost ratio (3.16) was also recorded higher with application 100% NPK based on ST-TY based along with 5 t/ha FYM. The nutrient uptake by crops and soil nutrients status were higher after three year of jute-rice cropping sequence when NPK were applied with FYM. Hence, combination of inorganic and organic (FYM) fertilizer could achieve target yield and maintain the soil fertility status.

Assessment of maize yield gap and major determinant factors between smallholder farmers in the Dedza district of Malawi

This study explored the effect of soil nutrient status, agronomic practices and socio-economic factors on maize yield attained by smallholder farmers in the Dedza District of Malawi. Results show that maize yield ranged between 0.4 and 12 t ha−1 with a mean value of 4.1 t ha−1. Observed high yields (>8.0 t ha−1) were associated with households using improved varieties combined with improved management practices such as NPK, urea and animal manure. With regards to soil factors, boron (B) and nitrogen (N) which are critically deficient in the area were significantly (β = 21.1, p < 0.01) associated with maize yield increase. From agronomic factors, weeds, seed spacing, plant density and fertilizer application played significant role in maize yield. Weed rating inversely impacted yield (β = −0.5; p < 0.001) where fields with the lowest weed rating had the highest yield (4.6 t ha−1) than those with the highest rating (2.3 t ha−1). Socio-economic factors such as household wealth, household members with off-farm employment, number of years the household head has been involved in farming decision making, access to agricultural advice and group membership also influenced agronomic practices and resulted in yield gap. Household wealth and off-farm employment contributed to increased yield while household head experience in farming had negative impact. Extension service impacted yield negatively which can be attributed to the low extension worker to farmer ratio. The study demonstrated that closing yield gap in maize mixed farming systems requires integrated approach to addressing agronomic, biophysical and socio-economic constraints.

Phylogenetic relatedness within Neotropical fern communities increases with soil fertility

AbstractAimTo examine the relative importance of gradients in soil fertility and rainfall for the phylogenetic structure of Neotropical forest fern communities, and to quantify how much the results are affected by phylogenetic resolution.LocationTropical lowland forests in Brazil (central Amazonia) and Panama (the Panama canal watershed).MethodsWe inventoried local fern communities at a total of 87 sites to model how their species richness and phylogenetic relatedness varied along gradients in soil fertility and rainfall. We produced a time‐calibrated species‐level molecular phylogeny of ferns, and quantified the phylogenetic relatedness of species within local communities using Faith's phylogenetic diversity (PD) and mean phylogenetic diversity (MPD). Calculations were compared for phylogenies resolved to the species and genus levels.Results(1) We found significant and consistent effects of soil nutrient status on local phylogenetic community structure in both regions. In contrast, phylogenetic structure showed only a weak or no relationship with rainfall. (2) In both regions, MPD declined with increasing soil fertility, which means that fern communities on poor soils consisted, on average, of less closely related lineages than fern communities on rich soils. (3) Different fern genera were over‐represented in different sections of the soil nutrient gradient. (4) Qualitatively similar results were obtained whether phylogenies were resolved to the species or the genus level.Main conclusionsOur results highlight the importance of edaphic variation in structuring plant communities over evolutionary time‐scales. Within the tropical forests studied, the effects of soil variation on local phylogenetic community structure seem to outweigh those of climate. Several fern genera show strong edaphic niche conservatism to either poor or rich soils, whereas many other genera have radiated to span a rather broad edaphic range. PD‐based measures are so dominated by deep relationships that genus‐level phylogenies are sufficient to investigate these patterns in tropical fern communities.

Vegetation Affects the Relative Abundances of Dominant Soil Bacterial Taxa and Soil Respiration Rates in an Upland Grassland Soil

Plant-derived organic matter inputs are thought to be a key driver of soil bacterial community composition and associated soil processes. We sought to investigate the role of acid grassland vegetation on soil bacterial community structure by assessing bacterial diversity in combination with other soil variables in temporally and spatially distinct samples taken from a field-based plant removal experiment. Removal of aboveground vegetation resulted in reproducible differences in soil properties, soil respiration and bacterial diversity. Vegetated soils had significantly increased carbon and nitrogen concentrations and exhibited higher rates of respiration. Molecular analyses revealed that the soils were broadly dominated by Alphaproteobacterial and Acidobacterial lineages, with increased abundances of Alphaproteobacteria in vegetated soils and more Acidobacteria in bare soils. This field-based study contributes to a growing body of evidence documenting the effect of soil nutrient status on the relative abundances of dominant soil bacterial taxa, with Proteobacterial taxa dominating over Acidobacteria in soils exhibiting higher rates of C turnover. Furthermore, we highlight the role of aboveground vegetation in mediating this effect by demonstrating that plant removal can alter the relative abundances of dominant soil taxa with concomitant changes in soil CO(2)-C efflux.

Effect of soil nutrient status on severity of seedling diseases and root rot of sorghum (Sorghum bicolor)

The hybrid NK283 was subjected to a range of nutrient element concentrations to determine their effect on predisposition of sorghum to seedling diseases and root rot. Emergence was not affected by soil nutrient status. Similarly N, P and K did not affect seedling disease severity or secondary root rot. Highly significant correlations with disease were recorded between soil acidity, expressed as pH, exchangable acid (Al+H), acid saturation and total cations. A linear increase in mesocotyl discolouration was recorded with decreasing pH, while secondary root discolouration increased significantly at pH(KCI)<4.6. A threshold value of approximately 15% acid saturation was recorded above which seedling diseases and secondary root rot increased significantly. Seedling length and post-emergence damp- ing-off were significantly related to the degree of mesocotyl discolouration. Plant length at 6, 9 and 12 weeks after planting was significantly related to effective root volume (ERV) which was calculated as ERV=(((100-root rot (%))/100)*root volume(ml)). It was concluded that soil acidity

Interaction between cultivar and soil fertility on grain yield, yield components and grain nitrogen content of wheat

The effect of soil nutrient status on the performance of four wheat cultivars was studied in a long-term field experiment at the University of Pretoria. The objective was to quantify the effect of soil nutrient status on yield, yield components and grain quality characteristics, using a split-plot design in a randomized complete block, replicated four times. Grain yield and nitrogen content differed between cultivars with SST 86 yielding 3903 kgha-1(2.47%N), Inia 4484 kgha−1(2.53%N), Kariega 4447 kgha−1(2.49%N) and Carina 6343 kgha−1(3.58%N). Increasing soil fertility increased grain yield, grain number, spikelet number, grains per spike, grains per spikelet, grain nitrogen, biomass and harvest index, but depressed kernel mass. Significant interactions between cultivar and soil fertility were observed for grain yield, grain number, biomass, harvest index and kernel mass. It is concluded that wheat cultivars differ in their potential to utilize limited soil nutrients to produce yield and quality.

The effect of soil nutrient status on prey utilization in four carnivorous plants.

The hypothesis that carnivorous plants are less responsive to prey at high soil nutrient levels than at lower levels (Givnish et al. 1984) is tested on four plant species (Drosera rotundifolia, Pinguicula alpina, P. villosa and P. vulgaris) from a subarctic environment. The response, measured in terms of seven characteristics (winter bud weight, winter bud nitrogen and phosphorus content, flowering frequency, total seed weight, seed number and weight per seed), was analysed. Although all species responded to prey supply the response varied depending on the characteristic and species concerned. In 5 cases (out of 28 tests) the hypothesis was supported, whereas in 1 case it was refuted, i.e. the response to prey was higher for plants supplied with soil nutrients. In the remaining three-quarters of the tests, responses to prey were not significantly different between the two nutrient levels. Thus, the hypothesis that the response to prey diminishes as soil nutrient availability increases was not supported by our findings. A modification of the model presented by Givnish et al. (1984) is therefore suggested. This modified model measures the cost of carnivory as loss in growth rate and assumes that responses to prey remain unchanged as the soil nutrient content increases. Although the distribution of carnivorous plants is still predicted to be limited mainly to wet and sunny but nutrient-poor sites, the modified model also allows for their occurrence in richer habitats, provided competition is low.

Patterns of litter nutrient concentration in some plantation ecosystems

Patterns of litter nutrient concentrations in plantations of Shorea robusta (sal), Tectona grandis (teak), Pinus roxburghii (pine) and Eucalyptus sp. (eucalypts) were studied. Concentration of Ca and N were greater than K, Mg and P, in all fractions of litter, irrespective of species. The nutrient concentrations, in general, were related to the tissue longevity and the species life-forms. The nutrient-concentration changes in the leaf-tissue were negatively correlated with the magnitude of the leaf-fall: in the case of sal for all the nutrients, in teak and pine for N and P only, and in eucalypts for none of the nutrients. These changes were due to the back-translocations of nutrients from the leaves prior to leaf-fall. The variation in the concentration of leaf-litter nutrients is not a species' attribute but depends upon the combined effect of soil nutrient status, growth of the stand and tree growth formations.

Effect of Soil Nutrient Status and pH on Nitrogen‐Fixing Algae in Flooded Soils

AbstractThe development of indigenous N2‐fixing algae in 10 of 12 flooded soils, as measured by acetylene‐reduction activity, was stimulated by the addition of phosphate. In P‐supplemented flooded soils, these algae generally developed readily at pH 7.3 or greater but poorly at pH 6.5 or less. Iron additions stimulated the activity of inoculated blue‐green algae in a phosphate‐amended flooded soil of pH 7.9 but not in a soil with a pH of 5.5. Indigenous algae in an acid soil (pH 4.8) were stimulated by CO2. Nitrogen fixation and development of indigenous blue‐green algae were correlated with pH and the levels of extractable K and of Ca and Mg in these soils, but not with the concentrations of organic matter, inorganic N, or extractable phosphate and Fe.