Nutrient deficiencies in central Australian semi-desert rangelands, with reference to decline in range condition.

1980 ◽  
Vol 2 (2) ◽  
pp. 151 ◽  
Author(s):  
MH Friedel ◽  
KM Cellier ◽  
KP Nicolson
Keyword(s):  
Field Study ◽  
Phosphorus Deficiency ◽  
Nutrient Status ◽  
Nutrient Deficiencies ◽  
Nitrogen And Phosphorus ◽  
Range Condition ◽  
Desert Rangelands ◽  
Open Woodland ◽  
Good Range ◽  
Nitrogen Phosphorus

Three central Australian' plant communities: Mitchell grassland, open woodland and mulga shrubland, were examined for evidence of nutrient deficiencies, particularly in association with poor range condition. Twelve nutrients were applied in various combinations to their soils in glasshouse pots trials. Two native grasses were grown in the Mitchell grassland and open woodland soils, while a native grass and a native chenopod were grown in the niulga shrubland soils. A field study with three nutrients was restricted to open woodland. The grasses grown in Mitchell grassland and open woodland soils responded to added nitrogen, phosphorus and sulphur. while the grass grown in mulga shrubland soil responded to added nitrogen and phosphorus only. The chenopod, grown in mulga shrubland soil, responded to calcium as well as to nitrogen and phosphorus. In the field study, nitrogen improved plant growth but not all species responded equally. Arisrida contorra, which acts as an indicator of poor range condition in open woodland. formed a greater proportion of the herbaceous biomass following the addition of nitrogen. No response to phosphorus and sulphur was detected in the field. In both Mitchell grassland and open woodland, decreaser species (those whose biomass contributes proportionately less to the total as range condition decreases) responded better under glasshouse conditions to phosphorus on soils from areas in poor range condition than on soils from areas in good range condition. Of the species which increase with decreasing condition. that from the grassland also responded better to phosphorus on soils from areas in poor range condition, while that from the woodland was insensitive to phosphorus. In the mulpa shrubland, range condition was not associated with nutrient status. Several nutrients may be deficient in central Australian rangeland soils but phosphorus is the only nutrient which is potentially more deficient in degraded rangeland soils than on healthy rangeland soils. The evidence for a relationship between range condition and phosphorus deficiency is, however, inconclusive.

Relationship of the ratio of chlorophyll a to chlorophyll b and Douglas-fir seedling nutrient status

1993 ◽  
Vol 23 (8) ◽  
pp. 1655-1662 ◽  
Author(s):  
Grant A. Bracher ◽  
Peter A. Murtha
Keyword(s):  
Chlorophyll A ◽  
Nutrient Deficiency ◽  
Nutrient Status ◽  
Douglas Fir ◽  
Chlorophyll B ◽  
Nutrient Deficiencies ◽  
One Year ◽  
Relationship Of ◽  
Nitrogen Phosphorus ◽  
Nutrient Solutions

One–year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings were treated with 24 nutrient solutions containing nitrogen, phosphorus, and sulphur levels ranging from 1 to 400 mg/L. After one growing season, newly matured needles were harvested, and foliar samples analyzed for nutrient and chlorophyll concentrations. Several nutrient deficiencies were diagnosed. A consistent and statistically significant relationship between the ratio of chlorophyll a to b and the severity of nutrient deficiency was not found; consequently, it appears ineffectual as an index of nutrient stress.

scholarly journals The SN2 reaction and its relationship with the Walden inversion, the Finkelstein and Menshutkin reactions together with theoretical calculations for the Finkelstein reaction

2021 ◽  
Author(s):  
Ibon Alkorta ◽  
José Elguero
Keyword(s):  
Linear Models ◽  
Theoretical Calculations ◽  
Computational Method ◽  
Basis Set ◽  
Free Energies ◽  
Nitrogen And Phosphorus ◽  
Atom Pairs ◽  
Leaving Groups ◽  
First Time ◽  
Nitrogen Phosphorus

AbstractThis communication gives an overview of the relationships between four reactions that although related were not always perceived as such: SN2, Walden, Finkelstein, and Menshutkin. Binary interactions (SN2 & Walden, SN2 & Menshutkin, SN2 & Finkelstein, Walden & Menshutkin, Walden & Finkelstein, Menshutkin & Finkelstein) were reported. Carbon, silicon, nitrogen, and phosphorus as central atoms and fluorides, chlorides, bromides, and iodides as lateral atoms were considered. Theoretical calculations provide Gibbs free energies that were analyzed with linear models to obtain the halide contributions. The M06-2x DFT computational method and the 6-311++G(d,p) basis set have been used for all atoms except for iodine where the effective core potential def2-TZVP basis set was used. Concerning the central atom pairs, carbon/silicon vs. nitrogen/phosphorus, we reported here for the first time that the effect of valence expansion was known for Si but not for P. Concerning the lateral halogen atoms, some empirical models including the interaction between F and I as entering and leaving groups explain the Gibbs free energies.

Water-Fertilizer Coupling Effects and Efficient Utilization under Peanut-Millet Interplanting Conditions

2013 ◽  
Vol 742 ◽  
pp. 272-277
Author(s):  
Liang Shan Feng ◽  
Zhan Xiang Sun ◽  
Jia Ming Zheng
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Coupling Effect ◽  
Field Capacity ◽  
Nitrogen And Phosphorus ◽  
Application Rates ◽  
Optimal Value ◽  
Factor Interactions ◽  
Nitrogen Phosphorus

In this study, the results showed that water is the most important factor to affect crop yields and optimum soil moisture is lower under the conditions of peanut-and-millet interplanting. Thus, peanut-and-millet interplanting is generally able to fit most of the semi-arid region. In the interaction of various factors, the coupling effect of water and phosphorus was stronger than the coupling effect of fertilizers, following by the coupling effect of water and nitrogen. Among peanuts factors of water, nitrogen, and multi-factorial interaction of water, nitrogen, and phosphorus, water and nitrogen showed a negative effect, whereas the two-factor interactions had a positive effect. There were some differences between peanut and millet in the need for water and fertilizer, in which peanut required more nitrogen and millet needed slightly higher soil moisture and phosphorus. When other factors were in rich level, both of the optimal value for single factors of water, nitrogen, and phosphorus and the optimal value for two-factor interactions of water-nitrogen, water-phosphorus, and nitrogen-phosphorus, were higher than the optimal value for the interaction of water, nitrogen, and phosphorus. The tiny demand difference on moisture in peanut-millet interplanting could be compromised by configuring a reasonable interplanting population structure and the corresponding demand difference on fertilizer could be resolved by uneven crop planting strips. Under the condition of water-nitrogen-phosphorus interaction, the soil moisture content optimal for peanut accounted for 57.3% of the field capacity, and the related appropriate application rates of nitrogen and phosphorus were 0.98 g/pot (81.18 kg/hm2) and 0.39g/pot (32.18 kg/hm2), respectively. Likewise, the soil moisture content optimal for millet was 59.1% of the field capacity, and the counterpart appropriate application rates of nitrogen and phosphorus were 0.57 g/pot (47.03 kg/hm2) and 0.45g / pot (37.13 kg/hm2), respectively.

Distribution of Biomass, Nitrogen, Phosphorus and Other Nutrients in Banksia marginata and B. ornata Shoots of Different Ages After Fire.

1986 ◽  
Vol 34 (6) ◽  
pp. 709 ◽  
Author(s):  
RH Groves ◽  
PJ Hocking ◽  
A Mcmahon
Keyword(s):  
National Park ◽  
Dry Matter ◽  
Lateral Roots ◽  
South Australia ◽  
Distribution Patterns ◽  
Nutrient Accumulation ◽  
Nitrogen And Phosphorus ◽  
Vegetative Organs ◽  
Western Victoria ◽  
Nitrogen Phosphorus

The heathland form of Banksia marginata Cav. regenerates rarely from seed but commonly by resprout- ing from buds on lateral roots, whereas Banksia ornata F. Muell. regenerates only from seed, usually released after fire. The two species co-occur in heath vegetation on nutrient-poor soils in south-eastern South Australia and western Victoria. Shoots were sampled from stands of B. marginata aged from 1 to 25 years and of B. ornata aged from 1 to 50+ years after fire in the Little Desert National Park, western Victoria. B. marginata, the resprouter, distributed a greater proportion of the total shoot dry matter and content of all nutrients to vegetative growth over its shorter life span than B. ornata, the non-sprouter. About 50% of the total phosphorus in B. ornata shoots at 50+ years was present in cones (including seeds) compared with only about 20% in B. marginata shoots at a comparable stage of senescence (25 years). This difference between the species was also true to a lesser degree for nitrogen. There were considerable differences between other nutrients in their distribution patterns in shoots. Nutrients could be grouped together on the basis of distribution in shoots more satisfactorily than on presumed physio- logical roles. Stems were major sites of nutrient accumulation in both species. The content of a particular nutrient in seeds as a proportion of the content in the living parts of the shoot ranged from 0.03% (Na, Mn) to 2.0% (P) in B. marginata, and from 0.3% (Na) to as high as 31% (P) in B. ornata. Concen- trations of all nutrients except sodium were much higher in seeds than in the woody cones or vegetative organs of both species; seeds of B. ornata were particularly rich in calcium and manganese. We conclude that the different patterns of distribution of biomass and nutrients, especially nitrogen and phosphorus, within shoots of the two species reflect their different regenerative modes after fire. Introduction Phosphorus and, to a lesser extent, nitrogen limit the growth of sclerophyllous shrubs on nutrient-poor soils in southern Australia

scholarly journals GIS based Soil Nutrient Assessment of Available Macro and Micronutrients in Tommaladahalli Microwatershed of Chikkamagaluru District, Karnataka, India

2021 ◽  
Vol 10 (9) ◽  
pp. 510-517
Author(s):  
S. Anitha ◽  
K. T. Gurumurthy Ganapathi
Keyword(s):  
Interpolation Method ◽  
Soil Nutrient ◽  
Nutrient Status ◽  
Nitrogen And Phosphorus ◽  
Available Nitrogen ◽  
Entire Study ◽  
Available N ◽  
Standard Procedures ◽  
Entire Study Area ◽  
Available Nutrient Status

An investigation was undertaken in Tommaladahalli (566.13 ha) micro-watershed of Tarikere taluk, Chikkamagaluru district of Karnataka to assess available nutrient status in the surface soils. About 118 surface soil samples were collected grid wise by using cadastral map at 250 m grid interval and were analyzed for their fertility status using standard procedures. Soil fertility maps were prepared by means of interpolation method called Krigging. The results revealed that the pH, electrical conductivity, and organic carbon were ranged from 5.37 to 9.06, 0.065 to 0.466 dS m-1 and 0.33 to 1.62 per cent respectively. The available N, P2O5, K2O were ranged from 175.6 to 545.6 kg ha-1, 11.8 to 61.1 kg ha-1 and 122.7 to 491.4 kg ha-1, respectively. The available nitrogen and phosphorus were low to medium, where as potassium content was medium to high in the entire study area. Micronutrients viz. zinc, iron and boron were sufficient and were ranged from 0.34 to 1.17 mg kg-1, 2.03 to 21.86 mg kg-1 and 0.30 to 0.89 mg kg-1 respectively.

scholarly journals Effect of Intercropping and Fertility Levels on the Nitrogen, Phosphorus and Potash Content and Uptake by Summer Pearlmillet (Pennisetum glaucum L.) under South Gujarat Condition

2021 ◽  
Vol 9 (3) ◽  
pp. 174-179
Author(s):  
K. R. Patel ◽  
Keyword(s):  
Pearl Millet ◽  
Phosphorus Content ◽  
Pennisetum Glaucum ◽  
P Uptake ◽  
Green Gram ◽  
Treatment Combination ◽  
K Uptake ◽  
Nitrogen And Phosphorus ◽  
College Of Agriculture ◽  
Nitrogen Phosphorus

A field experiment was conducted at College Agronomy Farm, N. M. College of Agriculture, Navsari Agricultural University, Navsari during summer, 2019 and 2020 comprising four intercropping treatments i.e. pearlmillet sole, pearlmillet+greengram, pearlmillet+cowpea, pearlmillet+clusterbean and three fertility levels viz., 75 % RDF, 100 % RDF and 125 % RDF. Among the different intercropping system examined, sole pearl millet (I1) accumulated significantly less content of N and P in pearl millet grain and straw as compared to intercropping with pulses treatments. Pearl millet + green gram (I2) recorded significantly higher N and P uptake by pearl millet straw than other intercropping systems. The sole pearl millet (I1) was at par with pearl millet intercropped with green gram (I2) had significantly higher K content and uptake in pearl millet grain and straw. In case of fertility levels, nitrogen and phosphorus content and uptake in pearl millet grain and straw were recorded significantly higher by application of 100 % RDF. Significantly higher N, P and K uptake by pearl millet grain and straw in pooled results were produced by treatment combination of pearl millet + green gram (I2) intercropping along with 75 % RDF (F1).

scholarly journals Laboratory study on the effects of nutrient enrichment on a phytoplankton population in Sawa Lake, Iraq

2008 ◽  
Vol 5 (2) ◽  
pp. 230-236 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Population Dynamics ◽  
Lake Water ◽  
Nutrient Enrichment ◽  
Cell Number ◽  
Shannon Index ◽  
Nitrogen And Phosphorus ◽  
Phytoplankton Population ◽  
Phytoplankton Cell ◽  
Nitrogen Phosphorus ◽  
Index Of Diversity

Nutrient enrichment of Sawa lake water was made using different nitrogen and phosphorus concentrations during autumn and spring at three stations. Different concentrations of nitrogen, phosphorus and N: P ratios were used to test variations in phytoplankton population dynamics. Nitrogen at a concentration of 25 µmole.l-1 and N: P ratio of 10:1 gave highest phytoplankton cell number at all stations and seasons. A total of 64 algal taxa dominated by Bacillariophyceae followed by Cyanophyceae and Chlorophyceae were identified. The values of Shannon index of diversity were more than one in the studied stations.

Interactive Effects of Nutrient Availability and Light Levels on the Periphyton Composition of a Large Oligotrophic Lake

1993 ◽  
Vol 50 (6) ◽  
pp. 1270-1278 ◽  
Author(s):  
Jane Claire Marks ◽  
Rex L. Lowe
Keyword(s):  
Interactive Effect ◽  
Oligotrophic Lake ◽  
Interactive Effects ◽  
Nitrogen And Phosphorus ◽  
Phosphorus Enrichment ◽  
Blue Green Algae ◽  
Nitzschia Palea ◽  
Nitrogen Levels ◽  
Light Levels ◽  
Nitrogen Phosphorus

We investigated the effects of nitrogen, phosphorus, and light on periphyton in a clear oligotrophic lake. Experimental treatments consisted of three levels each of nitrogen, phosphorus, and light in a three-way factorial design. Nitrogen and phosphorus concentrations were manipulated using nutrient-diffusing clay substrates; light levels were manipulated with shade cloth. Periphyton biovolume and cell densities increased significantly with both nitrogen and phosphorus enrichment but were not affected by shading. Phosphorus enrichment increased periphyton accumulation only when nitrogen levels were high, indicating a significant interactive effect between nitrogen and phosphorus. Differences in species composition among treatments were mostly due to changes in the diatoms Nitzschia palea and Rhopalodia gibba. Ambient and phosphorus-enriched substrates were dominated by R. gibba, which contains a nitrogen-fixing endosymbiont, and blue-green algae. Nitrogen enrichment and nitrogen and phosphorus in combination resulted in an assemblage dominated by N. palea. Unshaded and highly shaded substrates were dominated by N. palea and Achnanthes minutissima, but the medium-shade substrates were dominated by R. gibba.

Kinetic modelling of microalgal growth and fucoxanthin synthesis in photobioreactor

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Xiaojuan Zhang ◽  
Junru Zhao ◽  
Jie Zhang ◽  
Shijing Su ◽  
Luqiang Huang ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Kinetic Parameters ◽  
Kinetic Modelling ◽  
Inhibitory Effect ◽  
Rate Equations ◽  
Phosphorus Concentration ◽  
Model Output ◽  
Nitrogen And Phosphorus ◽  
Nitrogen Phosphorus

Abstract This paper presented a mathematical model to describe the production of fucoxanthin by alga Thalassiosira weissflogi ND-8 in photobioreactor. Our interest was focused on characterizing the effects of nitrogen and phosphorus on the growth of microalgae and on the synthesis of fucoxanthin. The rate equations of microalgal growth, fucoxanthin synthesis and substrate consumptions were formulated. Kinetic parameters of the model and their sensitivities with respect to model output were estimated. The predicted results were compared with experimental data, which showed that this model closely agrees with actual experiment and is able to reflect the growth and metabolism characteristics of microalgae. Our results also indicated that nitrogen plays a major role in the synthesis of fucoxanthin, and the synthesis of fucoxanthin is partially linearly related to the consumption of nitrogen. Phosphorus is primarily consumed in the growth and metabolism of microalgal cells, while excessive phosphorus concentration has an inhibitory effect on the growth of microalgae.

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