Effect of crop duration and soil type on the ability of soil sulfur tests to predict plant response to sulfur

Soil Research ◽  
1997 ◽  
Vol 35 (5) ◽  
pp. 1131 ◽  
Author(s):  
Nanthana Chinoim ◽  
Rod D. B. Lefroy ◽  
Graeme J. Blair

Soil testing for sulfur (S) is becoming increasingly important as soils become more S-deficient due to lower S inputs in fertiliser and higher offtake in product. Because of the differing rates of S supply required by a range of crops, the relative importance of the soil sulfate and organic S pools could be expected to vary between crops. A glasshouse experiment was conducted using an Aquic Haplustalf of granitic origin and an Ultic Haplustalf of basaltic origin collected from unfertilised pasture sites on the Northern Tablelands of New South Wales from Uralla and Walcha, respectively. The soil was labelled with 35S. The experiment consisted of 2 rates of S fertiliser (0 and 17·7 mg/kg soil, equivalent to 0 and 30 kg S/ha), 3 crop species (radish, corn, ryegrass), and 2 soils (granite and basalt). S was extracted using 2 extracts, mono-calcium phosphate (MCP) and 0·25 M KCl heated at 40°C (KCl-40), termed primary extracts, and the components of S in the extracts were determined. The relationship between the amount of S removed from the extract (S before planting – S after cropping) by the 2 test extractants in the – S treatment and plant S uptake was also determined. A higher S concentration was found in the KCl-40 extract than in the MCP extract in the granite soil. Conversely, the MCP extract had a higher S concentration in the basalt soil because of the relative size of the adsorbed S and ester-S pools in this soil. More than 33% of the 35S was recovered in the extracted S pool, and <11% from the organic S pool in both extractants and in both soils. Data showed a lower specific activity (SA) of the S in the MCP extract as measured by ICP than in KCl-40 in both soils and all crops. The specific activity ratio of the extractants, as measured by ICP, was closest to 1·00 for the KCl-40 extract in both soils for each crop. The removal of S from the MCP extractant during cropping was lower than plant uptake in all treatments except ryegrass in the basalt soil. The KCl-40 extract tended to underestimate S supply at low uptake and overestimate at higher uptake. The results reported in this experiment showed that the KCl-40 extract generally performed well for all 3 crops and on both soils. The data showed that the KCl-40 extract removed S from pools similar to those reached by the crops.


1998 ◽  
Vol 38 (6) ◽  
pp. 567 ◽  
Author(s):  
G. C. Anderson ◽  
R. D. B. Lefroy ◽  
G. J. Blair

Summary. A glasshouse experiment was conducted to study the correlation between various soil sulfur (S) extractants and pasture response to applied S grown under controlled environmental conditions (glasshouse) as influenced by variations in levels of extractable S. Intact paired soil cores were collected at 2-month intervals from an S x P factorial experiment at 4 field sites on the Northern Tablelands of New South Wales on 11 occasions. Soil samples were collected from each core and the cores placed in the glasshouse. Sulfur was applied to one core of each pair and basal nutrients applied to all cores which were then oversown with white clover (Trifolium repens L. cv. Haifa). The extractable S in the soil was analysed using the following techniques: 0.1 mol Ca(H2PO4)2/L (MCPt); 0.1 mol Ca(H2PO4)2/L, treated with activated charcoal (MCPi); water (H2O); 0.25 mol KCl/L, heated at 40°C for 3 h (KCl-40); 0.25 mol KCl/L, heated at 100°C for 4 h (KCl-100); 0.5 mol NaHCO3/L (NaHCO3); and an acid digestion of the soil (total). Dry matter yield and S content of the pasture shoots were measured for each 2-month growth period. The relationship between the various soil S extraction techniques and the response of pasture to applied S varied over time and was influenced by the level of inorganic S present in the soil and the amount of organic S extracted. When the level of MCPi-extractable S ranged between 2 and 22 µg S/g soil due to the application of fertiliser (summer 1987–88 and autumn 1988), or after a period of high mineralisation rates (spring 1988), the MCPi, MCPt, H2O and KCl-40 techniques had the highest correlation with the increase in S content of the pasture when S was applied. The higher correlation for the MCPt, H2O and KCl-40 techniques than the MCPi technique indicates that plants obtained some S from the organic S pool. In contrast, when the levels of MCPi-extractable S ranged between 2 and 10 µg S/g soil and the rate of mineralisation increased in response to an increase in soil temperature (June 1988 and June 1989) or moisture (September 1989) upon transfer of samples from the field to the glasshouse, the MCPt, H2O and KCl-40 techniques underestimated the available S pool and had lower r2 values than either the KCl-100 or NaHCO3 techniques.



1970 ◽  
Vol 10 (43) ◽  
pp. 196
Author(s):  
WM McArthur ◽  
K Spencer

A scheme is proposed as a basis for soil fertility studies in areas where little information is available. The first stage consists of sampling the area on a grid and determining the patterns of variation in the status of those nutrient elements likely to be deficient. These patterns are then compared with intensity patterns of environmental (including edaphic) variables. Where the two sets of variables can be quantified, regression analysis may be used to estimate the closeness of the relationship ; otherwise the relationship must be assessed visually from the degree of conformity between patterns. Those environmental variables that relate, causally or otherwise, to the distribution of components of chemical fertility are identified by strong correlations. Information so gained may be used in subsequent agronomic studies, both as a guide to number and location of field plots and as a framework for studies in soil chemistry and pedology. The scheme is illustrated using data derived from studies on the Dorrigo Plateau of New South Wales. Factors relating closely to phosphorus, sulphur, molybdenum, and nitrogen distribution were identified. In no case could one factor be used to predict the adequacy of all nutrients.



2006 ◽  
Vol 46 (10) ◽  
pp. 1301 ◽  
Author(s):  
S. L. Davies ◽  
A. M. Storrie ◽  
A. S. Cook ◽  
R. A. Latta ◽  
A. D. Swan ◽  
...  

Farmers often experience inconsistent responses when using herbicides to terminate an established lucerne pasture prior to cropping. In an attempt to redress this problem, a series of field experiments were conducted between 1999 and 2002 at various locations in southern and northern New South Wales, the Australian Capital Territory, and south Western Australia that aimed to identify management guidelines that improved the efficacy of herbicide mixtures commonly used to remove lucerne. Collectively, these studies indicated that herbicides were generally less effective when applied either early (less than 2 weeks) or late (6 weeks or more) in the regrowth cycle of lucerne after defoliation. Herbicide efficacy tended to be greatest if applied to regrowth 3–5 weeks after defoliation, which corresponds to a time when the lucerne crown and root reserves are likely to be in the process of being replenished by photoassimilates transported from the shoot. The impact of timing of herbicide application in relation to season was compared at a number of locations. Across all the sites and years, spring herbicide applications were generally the most effective, removing on average 87% of the lucerne (range 53–100%) compared with 72% in summer (24–100%) and 60% in autumn (7–92%). Spring applications were also more consistent in their effect, removing >80% of the lucerne plants in 9 out of 12 experiments, whereas similar rates of removal occurred on 4 occasions in 9 summer applications and only twice in 8 autumn applications. Some of the seasonal variation could be explained by differences in the amount of rainfall prior to herbicide applications. It was assumed that the relationship between rainfall and herbicide efficacy reflected the stimulation of lucerne shoot and root growth by the additional soil moisture before herbicide treatment. Herbicide mixtures that contained ingredients such as picloram that retain residual activity in the soil tended to be more effective and were less influenced by lucerne growth and season than those herbicides with little or no residual activity. However, such chemicals could potentially restrict which crops can subsequently be grown after a lucerne pasture has been removed. It was concluded that >80% of lucerne plants were likely to be removed using herbicides provided that the herbicide treatment was applied to actively growing lucerne 3–5 weeks after defoliation, and when greater than 70–95 mm rain had fallen in the 6–8 weeks prior to application.



2002 ◽  
Vol 14 (4) ◽  
pp. 431 ◽  
Author(s):  
J. C. Noble ◽  
G. H. Pfitzner

William Rodier (1859–1936) became well known throughout much of southeastern Australia during the late nineteenth and early twentieth centuries, mainly through the vigour with which he expressed his contentious views on how best to control certain vertebrate pests. Much of his 'plan', particularly in regard to rabbits, was based on his experience as a pastoralist in western New South Wales. In this article, we examine what is known about Rodier's family background, his occupations, preoccupations, and particularly, the effectiveness of his endeavours to convince a largely sceptical public as to the wisdom and practicality of his method for vertebrate pest control. Some of the circulars and flyers printed by Rodier are also reproduced for illustrative purposes. These were designed to demonstrate the effectiveness of the Rodier Method, especially for controlling the rabbit, perceived by him to be the most serious threat then facing landholders in Australia. Rodier's activities are appraised in light of the relationship then existing between community-based science and more orthodox, academically-based science in the late nineteenth and early twentieth century. Finally, this relationship is further explored in an historical context by examining the importance attached to local, informal knowledge in contemporary ecological research where landholder collaboration is now often regarded as an integral component.



1981 ◽  
Vol 32 (2) ◽  
pp. 227 ◽  
Author(s):  
SF Rainer ◽  
RC Fitzhardinge

The relationship between spatial patterns in the physical environment and patterns in community and trophic structure in the benthic fauna was investigated in an estuary with periodic deoxygenation of the near- bottom water. Six sites were sampled between intertidal mangroves and an 8 m deep basin of Port Hacking, N.S.W. A total of 163 species was collected, ranging from 11 to 94 at each site. Both frequency and biomass were least in the central basin and highest in a bed of the seagrass Zostera capricorni Aschers. The abundances at these sites encompass the range of values previously recorded for estuaries on the east coast of Australia. The dominant species differed from those reported from other New South Wales estuaries, although the same species were usually present. The distribution of common species was limited by fluctuations in dissolved oxygen levels, but not obviously so by sediment differences or short-term fluctuations in water temperature or salinity. Frequency-based diversity and evenness values were similar to those from other estuarine areas. Biomass-based values were lower at most sites than frequency-based values. Patterns of diversity and evenness could not be simply interpreted as indicators of environmental harshness in the community.



Author(s):  
Emma K. Austin ◽  
Tonelle Handley ◽  
Anthony S. Kiem ◽  
Jane L. Rich ◽  
David Perkins ◽  
...  

Drought is a threat to public health. Individual and community adaptive capacity is crucial when responding to the impacts of drought. Gaps remain in the understandings of the relationship between wellbeing and adaptive capacity, and whether increased wellbeing can lead to improved adaptive capacity (or vice versa). This paper explores the relationship between drought, wellbeing and adaptive capacity to provide insights that will inform actions to enhance adaptive capacity, and hence increase opportunities for effective drought adaptation. The theory of salutogenesis and the associated sense of coherence (SOC) are used to measure adaptive capacity and to explain why some individuals remain well and adapt to adversity while others do not. An online survey of rural residents (n = 163) in drought-affected New South Wales (NSW), Australia, was conducted from November 2018 to January 2019. Linear regression was used to model the relationships between SOC, sociodemographic factors, drought and wellbeing. Findings demonstrate that SOC is strongly correlated with wellbeing. Drought condition did not influence adaptive capacity, although adaptive capacity and drought-related stress were only weakly correlated. Increased wellbeing was found to be associated with stronger adaptive capacity and therefore, an individuals’ capacity to cope with adversity, such as drought.



1970 ◽  
Vol 10 (47) ◽  
pp. 802 ◽  
Author(s):  
DW Turner

The effects of plastic bunch covers and varying defoliation treatments on bunch weight were measured on Williams bananas at Alstonville in north-eastern New South Wales. Bunch covers did not significantly affect bunch weight. The number of leaves left on the plant at bunch emergence only reduced yield when less than four leaves were present. Leaf length duration was calculated and was positively related to bunch weight. Bunch covers did not alter the relationship between leaf number and yield. The rate of sucker growth and water relations within the plants were altered by defoliation treatments. Both of these effects were greatest when less than three leaves were left on the plant.



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