Soil treatment, plant species, and management effects on improved pastures on a solodic soil in the semi-arid subtropics: 3. Improving cool season plant and cattle productivity

1994 ◽  
Vol 34 (2) ◽  
pp. 145 ◽  
Author(s):  
JS Russell

Seasonal analyses of grasses and legumes in a long-term experiment on a solodised solonetz soil (Natrustalf) in southern Queensland showed that the large liveweight losses of steers in the cool months (June-August) appeared to be broadly correlated with low plant nitrogen (N), phosphorus (P), and potassium (K) concentrations. Annual variation in the N, P, and K percentages of Rhodes grass (Chloris gayana) and volunteer grasses [medics (Medicago spp.) and siratro (Macroptilium atropurpureum)] as affected by soil and plant treatments were examined by fitting a Fourier series to the data. Cool season liveweight losses of steers ranged from 391 glday with sown grasses alone to 11 g/day with sown grasses and medics plus lime and gypsum. The N content of volunteer and sown grasses ranged from 0.56 to 0.70% in the cool months, which is below the accepted N requirement of 1%. The P concentration of volunteer grasses was only 0.08%, but where P fertiliser was applied, concentrations in Rhodes grass were 0.10-0.11%. Potassium levels were also low in the cool months, with values of 0.23-0.43% in grasses. Exchangeable magnesium (Mg) and sodium increased from 1.3 and 0.48 mLJ100 g at 0-10 cm depth to 8.5 and 5.2, respectively, at 40-70 cm. Exchangeable calcium decreased from 2.5 mL/100 g at 0-10 cm to 0.40 at 40-70 cm. The Mg levels in siratro (0.58-0.60%) were higher than those in Rhodes grass (mean 0.12%). Medics responded markedly to lime, resulting in a 54% increase in steer liveweight gains on Rhodes grass-medic pastures. The use of lime on solodic soils for reducing both surface soil acidity and exchangeable aluminium increased plant and steer productivity. The cost of lime transportation can be high in inland areas, but small limestone deposits have been identified on the Darling Downs and these merit closer attention.


Soil Research ◽  
1974 ◽  
Vol 12 (2) ◽  
pp. 147 ◽  
Author(s):  
IF Fergus ◽  
AE Martin

Five soils were cropped with four plant species in pot experiments in the glasshouse, without addition of potassium, until growth virtually ceased, after which the depleted soils were replanted with either the same species, or a different one, to test the reproducibility of the 'exhaustion' conditions imposed. Uptake of potassium by the plants exceeded the changes in exchangeable potassium in four soils; the excess amounts taken up differed markedly between species and these differences were reproducible on replanting. Uptake by setaria (Setaria anceps) and siratro (Macroptilium atropurpureum) exceeded that by Rhodes grass (Chloris gayana) and lucerne (Medicago sativa), except for one swelling clay soil from which uptake by lucerne equalled that by siratro. Most of the differences between species were attributed to the uptake of initially non-exchangeable potassium, which was removed in significant amounts from three of the soils. For these three soils, uptake from non-exchangeable sources was detected only after about 80% of the exchangeable potassium had been removed. It is postulated that the efficiency of plant removal of non-exchangeable potassium from soil is directly related to the degree to which plant roots can lower the concentration of potassium in the soil solution.



2017 ◽  
Vol 44 (9) ◽  
pp. 899 ◽  
Author(s):  
Gustavo G. Striker ◽  
Cecilia Casas ◽  
Xiaolin Kuang ◽  
Agustín A. Grimoldi

Elongation-induced leaf emergence is one way for plants to deal with complete submergence by ‘escaping’ from water. This growth strategy is hypothesised to be more beneficial under single long-term submergence than under repeated short-term submergence events (i.e. fluctuating environment), as costs of repeated plant ‘adjustment’ would exceed the initial benefits of shoot elongation. To test this idea, 2-week-old plants of Chloris gayana Kunth. cv. Fine Cut (a submergence-tolerant cultivar first selected by a screening experiment) were grown for 4 weeks under (i) control conditions, (ii) two 1-week submergence cycles, or (iii) one 2-week submergence cycle. Additionally, a set of plants were placed below nettings to assess the cost of remaining forcedly submerged. Impeding leaves emergence through nettings did not compromise survival when submergence was 1-week long, but determined the death of all plants when extended to 2 weeks. Growth as affected by flooding regime revealed that under one 2-week submergence event, plants accumulated a 2.9-fold higher dry mass than when they experienced the same submergence duration in separate events along 1week. The ‘escape’ strategy in the grass C. gayana, by which leaf contact with air is re-established, is essential for its survival, and it is more beneficial for plant growth under long-term submergence than under repeated short-term submergence cycles.



1974 ◽  
Vol 14 (67) ◽  
pp. 186 ◽  
Author(s):  
RW Strickland

Dry matter production and quality of 45 Digitaria accessions were measured over the period 1964-70. In three experiments at Samford, south-east Queensland, the accessions were fertilized with either 336 or 672 kg ha-1 of N a year and cut four-weekly. Both total and cool season production was measured. Highest annual yields were produced by D. smutsii (40,000 kg ha-1), D. macroglossa (37,000 kg ha-1) and D. decumbens (30,000 kg ha-1). D. decumbens yielded up to 5000 kg ha-1 dry matter between May and September compared with up to 6800 kg ha-1 from D. pentzii, 6700 kg ha-1 from D. macroglossa and 6400 kg ha-1 from D. smutsii. In two other experiments persistence and production of nine accessions were compared with those of Rhodes grass (Chloris gayana) on heavy, gilgaied clay soil at Meandarra, Queensland and with Panicum coloratum var. makarikariense on a shallow, self mulching, sedentary black earth at Southbrook, Queensland. D. decumbens showed the greatest potential for persistence and production at Meandarra and one strain of D. smutsii had the greatest yields at Southbrook. Digestibility and mineral content varied little between species and were generally satisfactory for animal production. Digitaria tended to be higher in phosphorus content than P. coloratum and C. gayana.



2005 ◽  
Vol 52 (4) ◽  
pp. 71-80 ◽  
Author(s):  
J.A. Wilsenach ◽  
W.P.M. van Bragt ◽  
P. de Been ◽  
M.C.M. van Loosdrecht

Simultaneous increases in wastewater loads and effluent quality demand improved nutrient removal techniques. A simple technique for nitrogen removal is post-denitrification with methanol. The trade-off between better effluent vs. methanol consumption is debatable. Methanol dosing is not only un-sustainable in the long term, but the cost of methanol is also becoming increasingly important. Urine contains 80% of the total nitrogen (N) and 50% of the phosphate in wastewater. Separate collection and treatment of urine could improve existing treatment works and diminish the need for post-denitrification. In this paper, a nitritation-denitrification process is proposed where 20–30% of the N in urine is removed with the COD available in urine. The treated urine consists of ammonium-nitrite, which is to be introduced to the anoxic zone of a conventional treatment plant. Optimal denitrification via nitrite is possible with COD from other wastewater sources. The case study presented here shows that 40–50% urine separation and improvement of the flow scheme would improve effluent quality from 19 to 10 g N/m3, which would eliminate the need for post-denitrification.





Phlebologie ◽  
2010 ◽  
Vol 39 (03) ◽  
pp. 133-137
Author(s):  
H. Partsch

SummaryBackground: Compression stockings are widely used in patients with varicose veins. Methods: Based on published literature three main points are discussed: 1. the rationale of compression therapy in primary varicose veins, 2. the prescription of compression stockings in daily practice, 3. studies required in the future. Results: The main objective of prescribing compression stockings for patients with varicose veins is to improve subjective leg complaints and to prevent swelling after sitting and standing. No convincing data are available concerning prevention of progression or of complications. In daily practice varicose veins are the most common indication to prescribe compression stockings. The compliance depends on the severity of the disorder and is rather poor in less severe stages. Long-term studies are needed to proof the cost-effectiveness of compression stockings concerning subjective symptoms and objective signs of varicose veins adjusted to their clinical severity. Conclusion: Compression stockings in primary varicose veins are able to improve leg complaints and to prevent swelling.



2017 ◽  
pp. 34-47
Author(s):  
Hoi Le Quoc ◽  
Nam Pham Xuan ◽  
Tuan Nguyen Anh

The study was targeted at developing a methodology for constructing a macroeconomic performance index at a provincial level for the first time in Vietnam based on 4 groups of measurements: (i) Economic indicators; (ii) oriented economic indicators; (iii) socio-economic indicators; and (iv) economic - social – institutional indicators. Applying the methodology to the 2011 - 2015 empirical data of all provinces in Vietnam, the research shows that the socio-economic development strategy implemented by those provinces did not provide balanced outcomes between growth and social objectives, sustainability and inclusiveness. Many provinces focused on economic growth at the cost of structural change, equality and institutional transformation. In contrast, many provinces were successful in improving equality but not growth. Those facts threaten the long-term development objectives of the provinces.



1960 ◽  
Vol XXXIII (IV) ◽  
pp. 630-636
Author(s):  
F.-E. Krusius ◽  
P. Peltola

ABSTRACT The study reported here was performed in order to examine the tap water of Helsinki for its alleged goitrogenous effect. In a short-term, 24-hour experiment with rats, kept on an iodine-poor diet, we noticed no inhibition of the 4-hour 131I uptake, as compared with that of animals receiving physiological saline instead of tap water. Two similar groups of rats receiving 1 and 2 mg of mercazole in redistilled water showed a distinct blockage of the 4-hour uptake, which proved the effect of this substance. In a long-term experiment of 5 weeks' duration there was no detectable difference in the body weight, thyroid weight and the 4-hour 131I uptake when the rats receiving tap water or distilled water to which 0.45 per cent of sodium chloride was added were compared with each other. Replacement of tap water by a 10 mg per cent solution of mercazole in redistilled water enlarged the thyroid to double its normal weight and increased the 131I uptake to approximately five times that of the controls. Thus our experiments failed to demonstrate any goitrogenous effect in the tap water of Helsinki. Changes similar to those produced by a long-term administration of mercazole, i. e. an enlargement of the thyroid and an increased thyroidal iodine uptake, have been shown to be due to milk collected from goitrous areas. The observations here reported confirm the importance of milk in the genesis of the goitre endemia of Helsinki. Attention is further called to the fact that a thyroidal enlargement combined with an increased thyroidal iodine uptake cannot always be taken as a sign of iodine deficiency because similar changes may be produced by the administration of goitrogens.



2010 ◽  
Vol 59 (2) ◽  
pp. 295-314 ◽  
Author(s):  
Imre Kádár

Egy műtrágyázási tartamkísérlet 32. évében, 2005-ben vizsgáltuk az eltérő N-, P- és K-ellátottsági szintek és kombinációik hatását a réti csenkesz (Festuca pratensis) vezérnövényű, nyolckomponensű, pillangós nélküli gyepkeverék termésére, fejlődésére és elemtartalmára. A termőhely mészlepedékes csernozjom talaja a szántott rétegben mintegy 3% humuszt, 3–5% CaCO3-ot és 20–22% agyagot tartalmazott, N és K elemekben közepesen, P és Zn elemekben gyengén ellátottnak minősült. A kísérlet 4N×4P×4K = 64 kezelést×2 ismétlést = 128 parcellát foglalt magában. A talajvíz 13–15 m mélyen helyezkedik el, a terület aszályérzékeny. A vizsgált 2005. évben azonban kielégítő mennyiségű (649 mm) csapadék hullott és annak eloszlása is kedvező volt. A gyep telepítése spenót elővetemény után 2000. szeptember 20-án történt gabona sortávra 60 kg·ha–1 vetőmaggal, amelynek 25%-át (15 kg) a réti csenkesz (Festuca pratensis); 21–21%-át (12,6 kg) a nádképű csenkesz (Festuca arundinacea) és az angol perje (Lolium perenne); 9%-át (5,4 kg) a taréjos búzafű (Agropyron cristatum), valamint 6–6%-át (3,6 kg) a vörös csenkesz (Festuca rubra), a réti komócsin (Phleum pratense), a zöld pántlikafű (Phalaris arundinacea) és a csomós ebír (Dactylis glomerata) tette ki. Főbb eredményeink: – A meghatározó N-trágyázás nyomán a szénatermés 5-szörösére emelkedett a két kaszálással a N-kontrollhoz viszonyítva. A maximális 10 t·ha–1 körüli légszáraz szénahozamokat a 300 kg N·ha–1·év–1 N-adag, valamint a 150 mg·kg–1 körüli AL-P2O5-, illetve 150 mg·kg–1 feletti AL-K2O-tartalom biztosította. Növénydiagnosztikai szempontból a nagy terméshez kötődő optimális elemtartalom 2% körüli N- és K-, illetve 0,2–0,3% P-koncentráció volt a szénában. – A két kaszálással felvett minimum (a 2 t·ha–1 körüli szénatermést adó N-kontroll) és maximum (a 10 t·ha–1 körüli szénahozamú, nitrogénnel és PK-vel jól ellátott talajok) elemmennyiségek a következőképpen alakultak: N 21–196 kg, K 39–188 kg, Ca 9–48 kg, Mg 4–22 kg, P 6–21 kg. – Az N×P és N×K kölcsönhatások kifejezettebbé váltak a 2. kaszálás idején. A P 0,18–0,55%, a NO3-N 86–1582 mg·kg–1, a Cu 4,7–7,4 mg·kg–1, a Mo 0,7–4,1 mg·kg–1 extrém értékeket jelzett az N×P kezelések függvényében. Az N×K kezelésekben a K 1,44–2,73%, a Mg 0,26–0,39%, a Na 71–2178 mg·kg–1, a Ba 4,1–9,6 mg·kg–1, a Cd 15–44 µg·kg–1 szélsőértékekkel volt jellemezhető. A Sr a 10–26 mg·kg–1 koncentrációtartományban módosult a P×K-ellátottság nyomán. Élettani, takarmányozástani szempontból az indukált kölcsönhatások nyomon követése elengedhetetlen, amennyiben olyan mérvű tápelemhiányok, illetve aránytalanságok jöhetnek létre, melyek anyagcserezavarokat okozhatnak a növényt fogyasztó állatban.



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