The effect of topdressed superphosphate on changes in nitrogen:carbon:sulphur: phosphorus and pH on a red earth soil during a long term grazing experiment

Soil Research ◽  
1977 ◽  
Vol 15 (2) ◽  
pp. 147 ◽  
Author(s):  
GD Kohn ◽  
GJ Osborne ◽  
GD Batten ◽  
AN Smith ◽  
WJ Lill

Increases in total nitrogen in a grazing experiment at Wagga Wagga (N.S.W.) over the years 1962-1966 were related to the levels of superphosphate applied (0-375 kg ha-1), the average rate of increase being 59 kg ha-1 year-1. The rate of change varied between years and was negative in a dry year. Total sulphur levels were not influenced by phosphate treatments (mean 150 ppm), but sulphate sulphur was only maintained by the highest superphosphate level. Total, aluminium, iron, calcium and 'available' phosphate increased with superphosphate levels. The level of aluminium-bound phosphate increased more rapidly than the other fractions. In the treatments without applied phosphate the aluminium bound phosphate declined more rapidly than the other fractions. Organic carbon was not influenced by treatments but showed an increase with time. The C:N ratio declined from 13 to 11.8 during the experiment. Soil pH declined by 0.18 pH units, but this was not affected by superphosphate levels. Stocking rates had no effect on these parameters of soil fertility.

2002 ◽  
Vol 53 (2) ◽  
pp. 115 ◽  
Author(s):  
J. W. D. Cayley ◽  
M. R. McCaskill ◽  
G. A. Kearney

Changes in soil pH from a long-term experiment at Hamilton, Vic., associated with time, fertiliser application, and stocking rate were assessed. The pH was measured in a 1 :5 suspension of soil in water (pHW) from 1980 onwards and in a 1:5 suspension of soil in 0.01 M CaCl2 (pHCa) from 1984 onwards. Topsoils (0–10 cm) were sampled regularly from 1980 to 1999, and the soil profile to a depth of 80 cm in 1994. The site was sown to perennial ryegrass, phalaris, and subterranean clover in 1977. Treatments fertilised with different amounts of superphosphate were grazed by sheep at stocking rates of 7–19 dry sheep equivalents (DSE)/ha. Average applications of phosphorus (P) ranged from 0.5 to 38.7 kg P/ha.year. The pHCa of the topsoil in 1984 was 4.9. It decreased at an average rate of 0.005 pHCa or 0.008 pHW units/year, with little variation due to fertiliser or stocking rate. Measurements in 1994 revealed subtle but statistically significant (P < 0.01) trends in soil pHCa that were associated with grazing pressure, inputs of fertiliser, and whether or not areas sampled were used by the sheep for camping. The top 0–5 cm of soil was slightly less acidic (+0.07 pHCa units) in the camp areas compared with non-camp areas. Below 5 cm to a depth of 80 cm, camp areas were more acidic (–0.19 pHCa units). At the highest stocking rates, heavier applications of superphosphate were associated with greater subsoil acidity: –0.06 pHCa units per 100 kg phosphorus (P) applied. There was no relationship at medium stocking rates. At low stocking rates, higher P applications were associated with more alkaline subsoils. Net removal of product from 1979 to 1994 (wool and meat removed from plots and excreta transferred to camps) was estimated to be equivalent to 140–380 kg/ha of lime over this 15-year period. The organic carbon (OC) content of the topsoil did not change over 20 years of records from 1979, and was unaffected by inputs of P. In 1994, the OC content of the 0–5 cm layer of topsoil was greater than the 5–10 cm layer (mean values 5.5% and 3.8% respectively; P < 0.001). The OC content of camp areas was higher than that of non-camp areas, this difference being more pronounced in the 0–5 cm layer (P < 0.01). It was concluded that the rate of change of pH was slow because of the high pH buffering capacity of the soil, the small amount of alkalinity removed in product, and the generally high perennial grass content of the pastures. Soils shown to be at greatest risk of acidification from this study were those under camp areas, and where high fertiliser rates were applied to pastures with a low perennial grass content. Rotational grazing should diminish these problems by reducing the concentration of excreta in camp areas, and favouring perennials over annuals in both camp and non-camp areas. Inputs of lime may eventually be needed to compensate for the acidifying effect of product removal.


1990 ◽  
Vol 36 (12) ◽  
pp. 2097-2101 ◽  
Author(s):  
K Emancipator ◽  
J L Bock ◽  
M D Burke

Abstract We compare three methods for using the rate of change of human choriogonadotropin (hCG) concentration in serum to diagnose ectopic pregnancy. With Method I, the lower limit for the rate of increase of serum hCG in normal pregnancy is 66% per 48 h. With Method II, a different lower limit of normal is specified for each of four discrete sampling intervals of hCG. With Method III, the lower limit of normal is determined by a continuous discriminant function of the initial hCG concentration. If the initial hCG concentration is less than or equal to 2000 int. units/L (Second International Standard), all three methods have acceptable diagnostic efficiencies, and there are no statistically significant differences among conclusions from the methods. None of the three methods performs satisfactorily if the initial hCG concentration is greater than 2000 int. units/L. We recommend Method I because it is simpler than the other two.


1975 ◽  
Vol 23 (4) ◽  
pp. 523 ◽  
Author(s):  
LR Clark ◽  
MJ Dallwitz

In 1958-63 and 1964-71 the life systems of four kinds of test-forming psyllid that coexist on Eucalyptus blakelyi were investigated intensively in a comparative study of insect abundance. This paper deals mainly with C. albitextura, which was kept under observation from 1950 to 1974. (The others were two species of Glycaspis, Spondyliaspis sp, and Creiis costatus.) The results indicate that the differences in maximal abundance reached by the four kinds of psyllid are mainly the outcome of differences in their ability tg utilize the leaves of the host plant as a source of food, C. albitextura being much more effective than the other species. For the latter, it appears that the principal environmental determinant of abundance was the number of feeding places where nymphs could survive long enough to complete development. That number varied according to foliage and weather. C. albitextura also differed from the other species by having its population densities held for long periods far below the levels at which the food supply would be limiting, by restrictions imposed upon reproduction by adverse weather and foliage conditions (the latter being due partly to poor synchronization between the emergence of adults in spring and the occurrence of foliage attractive for oviposition), and by high mortalities due to natural enemies. The life system of C. albitextura lacks an element that can stabilize abundance at low population densities, but adverse environmental influences usually limit the rate of increase greatly when abundance is low. The magnitude of the average rate of increase to high levels of population density, and the length of time for which high average densities are maintained, depend upon the frequency with which favourable conditions of weather, foliage and predation combine to promote both survival and reproduction.


1977 ◽  
Vol 17 (88) ◽  
pp. 802 ◽  
Author(s):  
DL Rowell ◽  
GJ Osborne ◽  
PG Matthews ◽  
WC Stonebridge ◽  
AA McNeil

A trial was established at Wagga Wagga, New South Wales in 1967 to examine the value of the bipyridilium herbicides as substitutes for mechanical weed control in an extended cropping phase of a cereal/clover ley rotation. The experiment was continued for seven years and the results indicate that herbicides can successfully substitute for mechanical weed control. Direct drilling with a tined combine/seeder into a sprayed but undisturbed seed bed yielded an average of 1.97 tonnes of grain per hectare over seven years compared with 2.02 tonnes per hectare in the mechanically prepared or cultivated seed bed. The difference in yield was not significant. Direct seeding with a triple disc seeder following spraying of an undisturbed seed bed gave significantly lower yields than the other minimum tillage treatments. This minimum cultivation treatment was not successful because of poor plant establishment, possibly emphasized by restricted root growth. A reduced cultivation technique-cultivate-spray-drill-which was included in the trial over the last five years, gave comparable yields, 2.1 7 compared with 1.90 tonnes per hectare, to those obtained by conventional cultivation methods. There were no significant increases in yield with added nitrogen in a dry season, but in four out of the other six years there was significant linear increase in yield with increasing nitrogen rate. There was no significant interaction between cultivation method and applied nitrogen, indicating that neither minimum nor reduced cultivation increased the requirement for nitrogen fertilizer. The results are discussed in terms of mechanical aspects that will allow greater disturbance of the soil beneath the seed with a view to obtaining optimum root development.


2014 ◽  
Vol 75 (1) ◽  
pp. 55-60
Author(s):  
Krzysztof Adamowicz ◽  
Henryka Kaciunka

Abstract The rate of change in the cost of logged timber and prices of raw timber during the period, 2001-2009, was examined for the Regional Directorate of the State Forests in Zielona Góra. A logarithmic evaluation of average rate of change indicated that the rate of increase in timber harvest costs was higher than the rate of increase in the average price of raw timber and likewise the price of most log grades. The average increase in raw timber value was 2.51% annually. The price of low-diameter raw timber (slash) increased 8.61%, and the price of large-diameter timber increased 1.94% annually, while the price of large coniferous segments increased 1.75% and broadleaf segments increased 2.98% annually. At the same time, the timber logging costs increased more than the timber price, to 4.17%, or 4.19% when administrative costs related to timber logging are included


2012 ◽  
Vol 12 (23) ◽  
pp. 11485-11504 ◽  
Author(s):  
D. D. Parrish ◽  
K. S. Law ◽  
J. Staehelin ◽  
R. Derwent ◽  
O. R. Cooper ◽  
...  

Abstract. Changes in baseline (here understood as representative of continental to hemispheric scales) tropospheric O3 concentrations that have occurred at northern mid-latitudes over the past six decades are quantified from available measurement records with the goal of providing benchmarks to which retrospective model calculations of the global O3 distribution can be compared. Eleven data sets (ten ground-based and one airborne) including six European (beginning in the 1950's and before), three North American (beginning in 1984) and two Asian (beginning in 1991) are analyzed. When the full time periods of the data records are considered a consistent picture emerges; O3 has increased at all sites in all seasons at approximately 1% yr−1 relative to the site's 2000 yr mixing ratio in each season. For perspective, this rate of increase sustained from 1950 to 2000 corresponds to an approximate doubling. There is little if any evidence for statistically significant differences in average rates of increase among the sites, regardless of varying length of data records. At most sites (most definitively at the European sites) the rate of increase has slowed over the last decade (possibly longer), to the extent that at present O3 is decreasing at some sites in some seasons, particularly in summer. The average rate of increase before 2000 shows significant seasonal differences (1.08 ± 0.09, 0.89 ± 0.10, 0.85 ± 0.11 and 1.21 ± 0.12% yr−1 in spring, summer, autumn and winter, respectively, over North America and Europe).


2020 ◽  
Vol 13 (1) ◽  
pp. 61-80
Author(s):  
Sutini Sutini ◽  
Iffana Fitrotul Aaidati ◽  
Kusaeri Kusaeri

[English]: This study aimed to identify students’ claim, evidence, and reasoning in covariational reasoning of constructing the graphs of a function. Covariational reasoning is one of the approaches to solve the problems of function. The study involved thirty grade 11 students. Data was collected through a covariation test and interview. The results of the test were grouped based on the criteria of mental action of covariational reasoning (Carlson et al., 2002), then the students who solve correctly two or three problems in the test were selected as the subjects. The interview data were analyzed to confirm and further dig students' structure of argumentation. The findings of this study indicate that only one student fulfils five mental actions of covariational reasoning; meanwhile, the other three students have similar components of argumentation which do not meet the mental actions. The claim and reasoning used by the latter students in covariational reasoning to construct graph are not identified in mental action 5 and the evidence is not found in mental action 3 (major coordination of change), mental action 4 (coordination the average rate of change), and mental action 5 (coordination of the instantaneous rate of change). Keywords: Argumentation, Claim, Evidence, Reasoning, Covariational reasoning [Bahasa]: Penelitian ini bertujuan untuk mengidentifikasi klaim, bukti, dan alasan siswa pada penalaran kovariasional dalam mengonstruk grafik fungsi. Penalaran kovariasional merupakan salah satu pendekatan dalam menyelesaikan permasalahan fungsi. Penelitian ini melibatkan 30 siswa kelas 11. Pengumpulan data dilakukan menggunakan tes kovariasi dan wawancara. Data hasil hasil tes kovariasi siswa dikelompokkan berdasarkan kriteria aksi mental penalaran kovariasional (Carlson et al., 2002), kemudian dipilih siswa yang mampu menyelesaikan minimal dua soal kovariasi. Data hasil wawancara dianalisis untuk mengonfirmasi dan menggali lebih dalam argumentasi siswa. Hasil penelitian menunjukkan hanya satu siswa yang memenuhi lima aksi mental penalaran kovariasional sedangkan ketiga siswa lain memiliki persamaan komponen argumentasi yang tidak memenuhi aksi mental. Untuk ketiga siswa tersebut, klaim dan alasan yang digunakan dalam membangun grafik fungsi tidak berada pada aksi mental 5 sedangkan bukti tidak berada pada aksi mental 3 (koordinasi besar perubahan), aksi mental 4 (koordinasi laju perubahan rata-rata), dan aksi mental 5 (koordinasi laju perubahan sesaat). Kata kunci: Argumentasi, Klaim, Bukti, Alasan, Penalaran kovariasional


2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.


2018 ◽  
pp. 49-68 ◽  
Author(s):  
M. E. Mamonov

Our analysis documents that the existence of hidden “holes” in the capital of not yet failed banks - while creating intertemporal pressure on the actual level of capital - leads to changing of maturity of loans supplied rather than to contracting of their volume. Long-term loans decrease, whereas short-term loans rise - and, what is most remarkably, by approximately the same amounts. Standardly, the higher the maturity of loans the higher the credit risk and, thus, the more loan loss reserves (LLP) banks are forced to create, increasing the pressure on capital. Banks that already hide “holes” in the capital, but have not yet faced with license withdrawal, must possess strong incentives to shorten the maturity of supplied loans. On the one hand, it raises the turnovers of LLP and facilitates the flexibility of capital management; on the other hand, it allows increasing the speed of shifting of attracted deposits to loans to related parties in domestic or foreign jurisdictions. This enlarges the potential size of ex post revealed “hole” in the capital and, therefore, allows us to assume that not every loan might be viewed as a good for the economy: excessive short-term and insufficient long-term loans can produce the source for future losses.


2018 ◽  
Vol 59 (1) ◽  
pp. 65-79
Author(s):  
Katarzyna Nikorowicz-Zatorska

Abstract The present paper focuses on spatial management regulations in order to carry out investment in the field of airport facilities. The construction, upgrades, and maintenance of airports falls within the area of responsibility of local authorities. This task poses a great challenge in terms of organisation and finances. On the one hand, an active airport is a municipal landmark and drives local economic, social and cultural development, and on the other, the scale of investment often exceeds the capabilities of local authorities. The immediate environment of the airport determines its final use and prosperity. The objective of the paper is to review legislation that affects airports and the surrounding communities. The process of urban planning in Lodz and surrounding areas will be presented as a background to the problem of land use management in the vicinity of the airport. This paper seeks to address the following questions: if and how airports have affected urban planning in Lodz, does the land use around the airport prevent the development of Lodz Airport, and how has the situation changed over the time? It can be assumed that as a result of lack of experience, land resources and size of investments on one hand and legislative dissonance and peculiar practices on the other, aviation infrastructure in Lodz is designed to meet temporary needs and is characterised by achieving short-term goals. Cyclical problems are solved in an intermittent manner and involve all the municipal resources, so there’s little left to secure long-term investments.


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