Effect of irrigation, nitrogen and defoliation on pangola grass in the dry season at the Ord Valley, north-western Australia

1978 ◽  
Vol 18 (95) ◽  
pp. 825 ◽  
Author(s):  
CG Blunt ◽  
KP Haydock

The effect of irrigation, cutting and nitrogen treatments on dry matter and nitrogen yield of pangola grass (Digitaria decumbens) growing in a calcareous clay soil in the Ord River Valley of northwestern Australia, was studied. Irrigation treatments ranged from 4-13 irrigations and nitrogen treatments from zero to 630 kg N ha-1 over the 5 months in each of two dry seasons. Cutting treatments to 15 cm at intervals of 2, 3, 6 and 12 weeks were applied only in the first year. In the first year dry matter yield (DM) increased from 3100 to 5200 kg ha-1 with an increase from 5 to 7 irrigations, a change of average daily available moisture from 78 to 107 mm, but there was no further increase from 13 irrigations (1 48 mm). DM increased linearly in the second year as average daily available moisture increased from 61 to 141 mm (4-12 irrigations). DM increased and N per cent decreased as cutting intervals increased. When cut at 2, 3 and 6-week intervals, pangola response in DM to nitrogen applied was linear, but was curvilinear when cut each 12 weeks. Average nitrogen recovery rates improved from 16 per cent to 30 per cent with an increase in nitrogen applied from 123 to 203 kg N ha-1 and remained at a similar rate to 630 kg N ha-1. Increased moisture improved apparent nitrogen recovery linearly to a maximum of 40 per cent at an average daily available moisture of 141 mm and 203-630 kg N ha-1 applied. For both DM and nitrogen yield the response to nitrogen and cutting frequency was proportional to the amount of moisture available. It was concluded that when cutting for hay at the Ord River, efficient use of applied nitrogen would be achieved by irrigating at least every two weeks, cutting about every 6 weeks and applying 250 kg N ha-1 during the dry season.

1988 ◽  
Vol 24 (2) ◽  
pp. 183-189 ◽  
Author(s):  
D. P. Singh ◽  
P. K. Singh

SUMMARYThe effects of phosphorus fertilizer and the insecticide carbofuran on the growth and N2-fixation of Azolla pinnata and on the growth, grain yield and nitrogen uptake of intercropped rice were examined in a wet and a dry season. Treatment with phosphorus or carbofuran increased the biomass of Azolla and the amount of nitrogen fixed (nitrogen yield) in both seasons, but the response was much better in the dry season. Azolla inoculation at 1.0 t ha−1 resulted in a greater bio mass and nitrogen yield than inoculation at 0.5 t ha−1. In the dry season, a combination of phosphorus and carbofuran enhanced the growth and N2-fixation of Azolla more than either treatment alone. Carbofuran treatment slowed the rate of decomposition of Azolla, particularly in the dry season. The plant height, leaf area index and dry matter production of rice at flowering time were increased in the plots treated with phosphorus or carbofuran in the wet season and these treatments increased rice grain yield and nitrogen uptake in both the wet and dry seasons.


1961 ◽  
Vol 56 (3) ◽  
pp. 407-410 ◽  
Author(s):  
M. H. Butterworth ◽  
C. G. Groom ◽  
P. N. Wilson

The intake of dry matter from a pasture of Pangola grass by lactating dairy cows was measured. The chromic oxide administration technique was used. It was shown that the intake of dry matter was significantly higher in the dry season than in the wet. Reasons for this were discussed. An assessment of the nutrient intake of the animals was made and it was concluded that if the requirements of cattle in temperate climates was taken as a guide, this was adequate for at least maintenance and production of 1½ gal. per day of milk in the wet season. Under dry season conditions the intake of total digestible nutrients was adequate for the same level of production, but the digestible protein level was considerably below requirement. It was therefore concluded that supplementation with protein concentrates in the wet season was unnecessary save for high-yielding cows, but that all cows required concentrates during the dry season conditions of the experiment.


1967 ◽  
Vol 7 (26) ◽  
pp. 225 ◽  
Author(s):  
MJT Norman ◽  
GA Stewart

In an experiment at Katherine, N.T., in the 1964, 1965, and 1966 dry seasons, Shorthorn steers were grazed on varying proportions of native pasture and standing Townsville lucerne pasture. The treatments were : a native pasture alone ; b Townsville lucerne two days, native pasture five days ; c Townsville lucerne four days, native pasture three days ; d Townsville lucerne alone. Liveweight gain over 16 weeks, from early June to late September, was linearly related to the number of days in the week on Townsville lucerne (21 = -74.9 + 2 7 . 9 � 30.5, where! = gain in lb per head and x = number of days). The results were compared with earlier data from Katherine on dry season supplementation of cattle on native pasture with a high-protein concentrate. In terms of liveweight gain, a weekly fall in dry matter yield of Townsville lucerne of 100 lb per head was equivalent to the consumption of 0.5 lb per head per day of digestible crude protein in concentrate form. Of this quantity of legume, it appeared that approximately two-thirds was consumed and one-third wasted. Periodic sampling of the Townsville lucerne pastures confirmed earlier findings that cattle grazing standing Townsville lucerne in the dry season do not select for a high-protein diet. The pattern of liveweight gain on Townsville lucerne alone, with other evidence, suggested that they do select for a high-energy diet.


1984 ◽  
Vol 24 (126) ◽  
pp. 410 ◽  
Author(s):  
BG Cook ◽  
JC Mulder

Nine tropical grasses were fertilized with 25, 50 and 100 kg N/ha on ten occasions at two-month intervals. No nitrogen was applied when conditions were too cold and/or dry for pasture growth. Samples (> 10 cm height) were taken at four-week intervals to estimate dry matter yield. Growth patterns of all grasses were similar, with a warm season peak and cool season trough. Nitrogen treatments did not greatly alter the growth pattern, although all species showed a yield response to increasing levels of nitrogen. Cumulative dry matter yields of Chloris gayana cvv. Callide and Katambora, Setaria sphacelata var. sericea cv. Narok, Digitaria decumbens and Panicum maximum cv. Makueni did not differ at N25 (P < 0.05), each producing about 10 t/ha. This significantly exceeded 5 t/ha from Pennisetum clandestinum cv. Whittet and Panicum maximum cv. Gatton. The same high-yielding group produced 15-16 t/ha at N50, while Gatton yielded 11.4 t/ha and Whittet 8.4 t/ha. At N 100, Callide, Katambora and Makueni were the highest yielding grasses (24-26 t/ha), and Whittet the lowest (15 t/ha). Brachiaria decumbens cv. Basilisk and Paspalum plicatulum cv. Bryan died out before the final harvests. Species responsiveness is discussed in terms of increment in dry matter yield per unit of applied nitrogen.


1977 ◽  
Vol 17 (88) ◽  
pp. 724
Author(s):  
L Falvey

A dry season meat-and-bone supplement fed to steers grazing improved legume-based pastures in northern Australia provided a significant liveweight advantage during three out of four dry seasons. An apparent negative response was attributed to a shortage of dry matter. Analyses of blood, bone and pasture samples and correlations of liveweight change with blood and bone measurements indicated the primary response to the supplement was probably to nitrogen. Feeding the supplement did not reduce the total time spent grazing but it did increase water consumption. The potential benefits of a protein supplement on improved pastures are discussed


2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Ruslan A. Gopar ◽  
S. Martono ◽  
Muhamad N. Rofiq ◽  
Windu N.

The objective of this experiment was to obtain forage/ cover crops productivity and carrying capacity for ruminant animals in Pelalawan Regency, Riau in the dry season. Data were collected from civil palm oil plantations at the aged 7, 10 and 14 years in the end of dry season with a destructive sampling method. Sampling used line intercept method which every hectare were picked 10 points by using a pair of 1 m2 sized quadrant. The result showed that the number of vegetations/ cover crops in oil palm plantations aged 7, 10 and 14 years was 42 types.The proportion of forage which consist grass, legume and ferns was diverse at each age of oil palm plantations. Forage production under oil palm plantations aged 7, 10 and 14 years were 2,571 kg/ha, 1479.76 kg/ha and 1417.22 kg/ha as fed and amounted to 811.41 kg/ ha, 471, 15 kg/ ha and 456.91 kg/ ha in the dry matter production. Average carrying capacities of oil palm plantations aged 7, 10 and 14 years was 0.36 Animal units (AU)/ha/year, 0.21 AU/ha/year and 0.20 AU/ ha/year.Penelitian ini bertujuan untuk mengetahui potensi jumlah covercrop dan kapasitas tampungnya di kebun sawit sebagai sumber pakan hijauan ruminansia pada musim kemarau di kabupaten Pelalawan, Riau. Pengambilan data dilakukan di perkebunan kelapa sawit yang berumur 7, 10 dan 14 tahun milik rakyat pada akhir musim kemarau. Pengambilan sampel dengan destructive sampling method menggunakan metode garis berpetak memakai kuadran berukuran 1m2 dengan jumlah sampel tiap area sebanyak 10 titik. Berdasar hasil pengukuran diperoleh hasil jumlah vegetasi/ covercrop yang ada di kebun sawit berumur 7, 10 dan 14 tahun sebanyak 42 jenis yang bervariasi tiap umur tanaman sawit. Proporsi hijauan yang ada meliputi jenis rumput, legume dan paku-pakuan bervariasi pada tiap umur kebun sawit. Produksi hijauan yang ada di bawah kebun sawit berumur 7, 10 dan 14 tahun berturut-turut 2.571 kg/ha, 1.479,76 kg/ha dan 1.417,22 kg/ha dalam bentuk segar serta sebesar 811,41 kg/ha, 471,15 kg/ha dan 456,91 kg/ha dalam bahan kering. Kapasitas tampung dari kebun sawit berumur 7, 10 dan 14 tahun adalah 0,36 satuan ternak (ST)/ha, 0,21 ST/ha dan 0,20 ST/ha.Keywords: cover crops, oil palm plantation, forage, ruminant, dry season, Pelalawan


2021 ◽  
Author(s):  
Hao Xu ◽  
Xu Lian ◽  
Ingrid Slette ◽  
Hui Yang ◽  
Yuan Zhang ◽  
...  

Abstract The timing and length of the dry season is a key factor governing ecosystem productivity and the carbon cycle of the tropics. Mounting evidence has suggested a lengthening of the dry season with ongoing climate change. However, this conclusion is largely based on changes in precipitation (P) compared to its long-term average (P ̅) and lacks consideration of the simultaneous changes in ecosystem water demand (measured by potential evapotranspiration, Ep, or actual evapotranspiration, E). Using several long-term (1979-2018) observational datasets, we compared changes in tropical dry season length (DSL) and timing (dry season arrival, DSA, and dry season end, DSE) among three common metrics used to define the dry season: P < P ̅, P < Ep, and P < E. We found that all three definitions show that dry seasons have lengthened in much of the tropics since 1979. Among the three definitions, P < E estimates the largest fraction (49.0%) of tropical land area likely experiencing longer dry seasons, followed by P < Ep (41.4%) and P < P ̅ (34.4%). The largest differences in multi-year mean DSL (> 120 days) among the three definitions occurred in the most arid and the most humid regions of the tropics. All definitions and datasets consistently showed longer dry seasons in southern Amazon (due to delayed DSE) and central Africa (due to both earlier DSA and delayed DSE). However, definitions that account for changing water demand estimated longer DSL extension over those two regions. These results indicate that warming-enhanced evapotranspiration exacerbates dry season lengthening and ecosystem water deficit. Thus, it is necessity to account for the evolving water demand of tropical ecosystems when characterizing changes in seasonal dry periods and ecosystem water deficits in an increasingly warmer and drier climate.


2002 ◽  
Vol 62 (2) ◽  
pp. 339-346 ◽  
Author(s):  
J. RAGUSA-NETTO

Figs are a remarkable food resource to frugivores, mainly in periods of general fruit scarcity. Ficus calyptroceras Miq. (Moraceae) is the only fig species in a type of dry forest in western Brazil. In this study I examined the fruiting pattern as well as fig consumption by birds in F. calyptroceras. Although rainfall was highly seasonal, fruiting was aseasonal, since the monthly proportion of fruiting trees ranged from 4% to 14% (N = 50 trees). I recorded 22 bird species feeding on figs. In the wet season 20 bird species ate figs, while in the dry season 13 did. Parrots were the most important consumers. This group removed 72% and 40% of the figs consumed in the wet and dry seasons, respectively. No bird species increases fig consumption from dry to wet season. However, a group of bird species assumed as seed dispersers largely increases fig consumption from wet to dry season, suggesting the importance of this resource in the period of fruit scarcity. The results of this study points out the remarkable role that F. calyptroceras plays to frugivorous birds, in such a dry forest, since its fruits were widely consumed and were available all year round.


1987 ◽  
Vol 109 (3) ◽  
pp. 445-452 ◽  
Author(s):  
M. J. Nicholson

SummaryThe effects of night enclosure and walking 3000 km on growing and breeding cattle were examined over an 8-month period. Walking consisted of an 8 h walk of 40 km every 3rd day and experimental cattle were enclosed each night for 11 h. In addition, all cattle were allowed water once every 3 days. In cattle which both walked and were enclosed, a reduction of nearly 40% in grazing time was recorded. This was associated with a depression of dry-matter intake of only 12%, suggesting an intensification of eating in response to a restriction of grazing time. The overall effects of walking and enclosing on productivity, as determined by adult weight loss, calf and weaner growth, calving percentage and birth weight, were negligible and masked by the greater effects of poor nutrition during the dry season which affected all the animals. It is concluded that the additional energetic requirements for walking are small and this is attributed to adaptation, fitness and a possible depression of metabolic rate. These factors may explain why the observed costs of walking were lower than those reported in the literature.


Author(s):  
Svetlana Vasil'evna Ivanova ◽  
Olga Vasil'evna Kurdakova ◽  
Aminat Msostovna Konova ◽  
Anna Yurievna Gavrilova

In the course of the experiment, the effect of increasing doses of nitrogen fertilizers on the yield of clover of the meadow variety Nadezhny, entered in the State Register of Breeding Achievements in 2012, was analyzed. A comparison is also made of this influence with the timothy of the meadow variety Leningradskaya 204. It was established that the pre-sowing introduction of mineral nitrogen for clover and timothy has influenced the productivity of these crops, but the nature of this effect varies depending on the type of grass. The introduction of N20 against the background of P30K90, which provided an increase in control of 51.2% for green mass and 33.6% for air-dry matter, was optimal for meadow clover of the first year of life. For grassland clover second year of life, the best option was N0P30K90, which gave an increase of 56.6% to the control on green mass and 50.6% on air-dry matter. A further increase in the dose of nitrogen on the options caused a decrease in yield increase. Timothy meadow for two years of life was traced responsiveness to the provision of nitrogen. The most productive in all respects was the option N120P30K90.    


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