Physical Sciences and Mathematics Commons^™

Grasslands For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world's grazing lands are a finite resource and, overall, arc being badly managed; in most developing countries action is required now, before it is too late. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will continue locally but, for much of what is now natural pasture, exploitation by the grazing animal .will remain the major means of obtaining an economic return; the task of grassland professionals is to assist the managers of …

Human Impact On Terrestrial Ecosystems - What We Know And What We Are Doing About It, H A. Mooney

IGC Proceedings (1977-2023)

At present the impact of humankind on the Earth System is substantial and will become greater as we continue to add over 80 million people to the global population each year. Collectively the human species utilises over a third of the total fresh water that is available, as well as an equivalent amount of the total terrestrial productivity. Possil energy is being consumed at a prodigious rate and fuels, among other things, over a half a billion vehicles. To support the large human population the Earth has been greatly reconfigured with much of the land utilised for grazing and agriculture. …

Science And Information For Our Grasslands, G A. Nores, R R. Vera

IGC Proceedings (1977-2023)

This paper favours a view of grasslands, and agricultural research in general, that extends well beyond the limits of the scientific community and promotes the active involvement of scientists in current societal debates from a scientific perspective. It is argued that in developed countries environmental concerns rather than production growth will tend to dominate future social debate. In developing countries there is a need to balance agricultural growth with responsible management of natural resources. Needs for new technology go beyond improving biophysical efficiency, and involve economic and social efficiency objectives. The relevance of grassland research is assessed in terms of …

Vegetation Dynamics In Grazed Systems: A Hierarchical Perspective, D D. Briske

IGC Proceedings (1977-2023)

Grassland vegetation consists of a series of hierarchical levels including the tiller, plant, population and community which collectively influence the productivity and stability of grazed systems. These hierarchical levels may respond uniformly to influence vegetation dynamics, but frequently additional complexity is encountered by the occurrence of opposing responses between or among hierarchical levels. Consequently, it is important to con­sider responses at several hierarchical levels to achieve an accurate interpretation of vegetation dynamics to graz­ing within the community. The significance of a hierarchical perspective to vegetation management is illustrated with examples from bunchgrass dominated rangelands at the level of the individual …

Forage Conservation And Physico-Chemical Conversion, E Zimmer

IGC Proceedings (1977-2023)

The factors on which the digestibility of organic matter (dMO) of forages depend are now well-known. In temperate forages, this digestibility depends mainly on the growth stage, the rank of the growth-cycle, and the botanical species. It is constantly decreasing with advancing age, especially during the first growth-cycle. In after­math growth-cycles, high temperatures accelerate the decrease of digestibility with age. Tropical forages follow the same laws, but tropical grasses are less digestible than cool-season grasses, especially at young stages and in warm weather. This is partly due to the fact that high temperatures increase cell-wall contents and lignification, and also …

The Feeding Value Of Forages, C Demarquilly

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

Nitrogen Fixation, Cycling, And Utilization, P M. Murphy, M T. Sherwood

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

La Prairie Dans Ses Usages Multiples: Conservation Des Sols, Protection De L'Environnement, Etc., M Skouri, J Poissonet

IGC Proceedings (1977-2023)

Les terres :i paturage couvrent une partie importante de la planete et presentent une extreme diversite de situations en fonction des conditions ecologiques et des facteurs socio-economiques et culturels qui s'exercent sur ces espaces. Ces facteurs ont engendre des transformations du milieu nature] permettant d'intensifier, et :i ]'extreme, de contr61er la production vegetale de ces ecosystemes. Si le role premier de ces formations herbacees a ete d'alimenter Jes herbivores afin que l'homme en obtienne une production (viande, lait, peaux, etc.), Jes autres fonctions de ces espaces ont une importance que !'on ne peut se permettre de negliger, que ce soit …

Quickening Snow Melting In Early Spring With Black Powder In Snowy District, A Imai

IGC Proceedings (1977-2023)

Experiments were conducted during 1977-1980 to quiken snow melting in early spring with three kinds of black powders at 450 m a.s.l.,Tsunan-machi, Niigata Prefecture. Snow melting materials involved blast furnace slag, di-amido lime and calcium silicate and their effects on snow melting were compared with each other at various application rates on snow surface in late March every year. Snow melting was earlier with 600 kg/ha di-amido lime resulting from lower albedo of 25 % and it could quicken the snow-off by 10-13 days as compared to the control plot. This early snow melting induced the higher soil temperature and …

Effect Of Fertilization In Autumn Or After Wintering On Dallisgrass Production In The Following Season, T Kobayashi

IGC Proceedings (1977-2023)

To improve dallisgrass (Paspalum dilatatum Poir.) pasture productivity, the effects of autumn or spring topdressing in a field experiment and autumn nitrogen (N) application levels in a pot experiment on the regrowth and carbohydrate accumulation until winter and on the early summer production were studied. Dallisgrass pasture was topdressed in either autumn (late September) or spring (early March) at 0.5 kg/a each of N, phosphate (P2O5), and potash (K20), after the final cutting in late September 1978. Plants in pots were topdressed at the rates of 0.5, 1, 2, and 4 kg N/a, just after cutting in early October …

Selenium Pellets Administration In Cows Grazing Continuously On Low Selenium Grassland In Japan, J Jachja, N Ishida, R Kawashima, K Otsuki, K Otsuki, M Kawano, F Hosoyamada

IGC Proceedings (1977-2023)

The effectof selenium (Se) supplementation in cows upon the growth of their newborn calves under the conditions of continuous grazing in a low Se pasture were studied. The selenium status of calves which were born from selenium treated cows were higher than that in calves from untreated control cows during the suckling period. Selenium supplementation to the dams showed no significant response upon the body measurement for their calves at birth or four months of age, but significant improvement in body weight and withers height at the weaning period. When cows grazed continuously in pastures containing a selenium content of …

Plant Introduction, Seed Production And Fodder Promotion In An Integrated Livestock And Pasture Development Programme In Kerala, India, A Shamsudeen, T V. Joseph, F Von Sury

IGC Proceedings (1977-2023)

An integrated pasture development programme for the state of Kerala, in the 1500-3500 mm rainfall area of southern India, is described. Kerala's agriculture is characterized by small holdings and intensive multicrop farming systems with coconut and rice as main crops. Dairy cattle rearing is an important subsidiary for many farmers. A plant introduction programme selected Panicum maximum ( cvs. Makueni and Riversdale), Brachiaria ruziziensis and Centrosema pubescens for intercropping in coconut gardens. Desmodium intortum and D. uncinatum were introduced for the grasslands of the high ranges. B. ruziziensis, Melinis minutiflora, Setaria anceps ( cvs. Kazungula and N arok), Stylosanthes guianensis …

Development Of Legume-Based Pastures For Livestock Production In Yunnan, Peoples Republic Of China- Preliminary Studies With Trifolium Semiplosum Cv. Safari And Temperate Legume Cultivars, M J. Mathison, M/S T. Wang, Z Y. Yang, M H. Dunning, Y N. Al, Z Z. Ma, H X. Al, L W. Peng, H Yang, D C. Zhang, C G. Zhang, G R. Yang

IGC Proceedings (1977-2023)

Aiming to improve livestock production from extensive grassland areas in Yunnan Province south west China, forage cultivar evaluation experiments are in progress as part of the China-Australia Technical Co-operation Programme. Preliminary results are given from introduced temperate legumes sown in 1983 in replicated swards in cultivated and uncultivated grassland. South west monsoon climates sampled range from alpine-temperate to tropical. In alpine sites red clover and annual species e.g. vetches, persian and subterranean clovers were among top dry matter yielders in the first year on cultivated land, Annual clovers failed or were outyielded by white, red clovers and, in one locality, …

Development Of Legume- Based Pastures For Livestock Production In Yannan, Peoples Republic Of China - Preliminary Studies With Tropical Legume Cultivars, M J. Mathison, M.S T. Wang, Z Y. Yang, Y N. Ai, Z Z. Ma, H X. Al, L W. Peng, G R. Yang

IGC Proceedings (1977-2023)

As part of the Australia -China technical cooperation programme investigations to raise livestock production with improved pastures began in 1983 in Yunnan province, south west China. Preliminary results with ungrazedintroduced tropical legume cultivars sown in cultivated and uncultivated grassland are given for 2000-2500m altitude subtropical sites and a 500m alt. tropical site. Only Jotononis, silverleaf and greenleaf desmodiums were productive in the second year at subtropical sites. At the tropical site annual lab lab produced most dry matter in the first year. Most perennial species grew well there in the second year. The best cul ti vars for cultivated land …

Fodder Development In The Dry Zone Of Sri Lanka - A Pasture Scheme For Small Farms, P Berger, L R. Abeykoon, L Winkler

IGC Proceedings (1977-2023)

A pasture development scheme to improve fodder production by small farmers was introduces by the Sri Lanka - Swiss Livestock Development Project (SSLDP) in the easten dry zone of Sri Lanka. The procedure of the scheme is described. Emphasis was put on proper land selection, establishment procedures and management factors of pasture plots. To promote the scheme a subsidy is given to the farmers after inspections by the extension staff. The first experiences showed a better survival of the plots under a closer follow up. A marked decrease was observed during extreme climatical periods. It is proposed to intensify the …

Range Improvement In Tropical China: Gaopoling Model Cattle Farm, D L. Michalk, J F. Ayres, Fu Nanping, Zhu Chin-Min

IGC Proceedings (1977-2023)

New policies seek to increase beef output on China's rangeland by sowing legume-based pastures. "Model farms" provide a means of quickly transferring this technology to China. Gaopoling Model Cattle Farm was set up to improve beef production in dry tropical Hainan Island by introducing new legume species and better husbandry practices. With finance from Guangdong Province and technology from Australia, a program emphasising pasture research, performance recording of "improved" versus "traditional" cattle husbandry and commercial farm developmant was commenced in 1981. Though experimentation, recommendations for species combinations, fertilizer inputs and sowing methods were formulated for the major local soil types. …

Preliminary Fertilizer Requirements For Establishing Legume Based Pastures In The Alpine Zoone Of Yunnan, Jinjing Wang, J R. Bruce-Smith, Jixin Li, Mingliang Wang

IGC Proceedings (1977-2023)

Preliminary results of field trials designed to assess the soil fertility status for establishing improved legume based pastures in the alpine zone of Yunnan Province are presented. These trials were undertaken by a joint Chinese-Australian Project which is investigating ways to improve the livestock industry of the Province. The best treatments at one site in the North East yielded about 9000kg of total (grass + legume + weeds) pasture and 7000kg of this was attributable to clover production. At another site in the North West on the Southern Tibetan Plateau summer waterlogging confined the pasture yield to 4000kg DM. Tentative …

Preliminary Studies Of Fertilizer Requirements Of Tropical Legumes In Southern Yunnans Red River Valley, Jinjing Wang, J R. Bruce-Smith, Mingliang Wang, Jixin Li

IGC Proceedings (1977-2023)

As part of a joint Chinese-Australian Project to promote livestock development, a farm site in the lower Chinese section of Red River Valley was chosen as an area to study techniques suited to meeting these objectives through establishing and utilizing legume based tropical pastures. Preliminary results of fertilizer trials at Daliuhu Farm show that sulphur deficiency is the main nutrient problem retarding the growth of siratro and stylo legumes. The application of as little as 5, but optimally between 10 and 20kg of sulphur as gypsum Sor elemental S seems to adequately meet their growth requirements. The apparent adequate phosphate …

Studies On The Mountain Pastures Classification And Class Evaluation Of Guichou, China, Huang Weilian

IGC Proceedings (1977-2023)

The pastures of the mountain range in Guichou are a secondary succession type, which has been shaped since the forest was destroyed. They were formed by forest regressive succession; from forest to bushwood, and with further degeneration from bushes to pastures. Therefore, in the author's opinion, it is appropriate to use the secondary succession series method of geobotany to classify the mountain range pastures in southern China. This method can objectively describe the origin and developing stages of this range type, the features of the vegetation succession series in subtropical areas, and express their economic value and utilization, which form …

The Grass Hillsides Of Jiangxi Province, Fan Xie, Suehen Wang

IGC Proceedings (1977-2023)

For researching into vegetation on grass slopes, their types, characteristics, yield and prospect of application in livestock husbandry, a sampling investigation on the semi-location spot has been carried out. Jiangxi province is situated in Southeast China, belonging to the monsoon region in Southeast Asia. According to the principles of ecological condition and dominant species, the grass hillsides can be classified into 7 herbosa groups: Ischaemum ciliare grass-land on hilly land, Arundinella setosa grass-land on hilly land, Dicranopteris dichotoma grass-land on hilly land of low hills, Miscanthus sinensis grass-land on hilly land of mid-low hills, M. floridulus grass-land on hilly land …

The Present Conditions Concerning Production And Utilization Of Forage Crops On The West Slope Of Mt. Fuji, S Mukaiyama

IGC Proceedings (1977-2023)

This report is mainly pointed out about the present situations with production and utilization of pasture and forage crops on the west slope of Mt. FUJI, and includes of some experimental studies and field surveys. Relative narrow areas in this region are divided into 3 regions such as subalpine, intermedial, and coastals from the standpoint of climatic condition and cropping systems. These regions have adaptable cropping and land usage. In the cropping pattern, subalpine is almost all pasture land, intermedial is combined with Sorghum or Maize and common ryegrass, and coastal is added tropical grasses such as Rhodes grass, Guinea …

On The Potential Productivity Of Orchardgrass Pasture (Dactylis Glomerata L.) In Japan And New Zealand, F Kubota, W Agata

IGC Proceedings (1977-2023)

A comparative discussion was made concerning the potential productivity of orchardgrass (Dactylis glomerata L.) and the climatic background of its growth in Japan (Asian monsoon climate) and in New Zealand (Temperate grassland climate). The potential productivity of orchardgrass pasture at four sites in Japan and 13 sites in New Zealand were predicted from air temperature and solar radiation at each site, using a production model. Annual potential productivity was larger as a whole in New Zealand. The seasonal variation of potential productivity in Japan presented markedly different patterns from site to site. While in New Zealand no large regional …

Light Interception, Productive Structure And Production Of The Phragmites Comminis Grassland In The Delta Of Nakdong River In Korea, H K. Kang, N K. Chang

IGC Proceedings (1977-2023)

Interception and absorption of sunlight, seasonal changes of productive structure, productivity, and standing crops of the Phragmites communisgrassland which was the pure stand in the delta of Nakdong river in Korea, were investigated in 1977,1982 and 1983.

The lighfpenetrating through the stratified canopies is decreased in sigmoid pattern. The cumulative leaf area of a definite space in a certain plant is the same as the growth of leaf area of the canopy at that time. When the leaf area grows according to the logistic equation, vertical accumulation of leaf area in a grassland is given by the general dynamic …

Snow Damage To Pasture Fences In The Highland Of Tohoku District Of Japan, Y Hosokawa

IGC Proceedings (1977-2023)

Since the snow damage to the pasture fences has been found in the snowy area of Japan, it is necessary to establish a guideline of the useful and durable fences for grazing cattle. The structural and material problems of the pasture fences were investigated in the subdivided fence lines corresponding to the topographical slant on each fence line. These fences constructed in the highland of Tohoku District of Japan were composed of steel posts, steel props, 4-barbed wire and small plates to fix the wire to the fosts. The barbed wire had two types: #14 barbed wire (zinc 2 coating …

Water-Spreading For Sown Crops And Pastures In Semi-Arid Rangelands, Richard W. Condon

IGC Proceedings (1977-2023)

There are many situations in semi-arid and arid rangelands where storm flows, normally running to waste or perhaps causing erosion or unwanted flooding further downslope, can be diverted to nearby relatively flat areas to augment soil moisture storage, making possible the growth of crops and pastures. The design, construction and general concept of spreader banks were tested under an incentive demonstration scheme in scrub-infested semi-arid rangelands of otherwise low productivity (1 sheep to 6-10 ha). Costs of development, including clearing of heavy timber, were recouped in 3-5 years, even though drought conditions prevailed for most of the time. The yield …

Tropical Grasslands As An Appropriate Agricultural Strategy In Northeast Thailand (Isan), D M. Mason

IGC Proceedings (1977-2023)

The diagnosis of the problem in Northeast Thailand (Isan) has been that it is relatively unsuitable for the production of rice ( Oryza sativa) due to insufficient rainfall and irregular weather patterns, in conjunction with excessively well-drained soils and topography which does not lend itself easily to irrigation technology. Despite such severe limitations, officials in the Royal Thai government and proponents of the Green Revolution have pushed hard for a rice industry in Isan. The results of such efforts have been a greater impoverishment of the population (Isan is and has long been the most economically depressed region in …

Pastures In Artificial Ponds For Dry Season Grazing In Tropical Australia, J H. Wildin

IGC Proceedings (1977-2023)

In tropical Australia beef cattle grow rapidly during the wet summer months when the native pastures are growing actively. In the dry season the native pastures are of low quality and cattle lose weight. Trapping runoff water during the wet months in artificial ponds to grow paragrass (Brachiaria mutica) for dry season grazing has been a very successful means of overcoming the dry season forage problem. In central Queensland the area planted to paragrass in artificial ponds exceeds 25 000 ha. Fattening steers are introduced to ponded paragrass in March-April. Weaners and breeding cows are given access when the …

Leucaena - A Permanent Dry Season Forage In Australia, J H. Wildin

IGC Proceedings (1977-2023)

Leucaena (Leucaena Jeucocephala) can play an important role in alleviating the general low pasture quality during the dry season. Extensive commercial use of leucaena for cattle grazing commenced in central Queensland in 1980 when the grazing management of this tree legume was modified to suit Australian beef producers. Plantings increased from 30 ha in 1979 to 3000 ha in central Queensland by February 1985. This rapid expansion can be attributed to beef producers being more aware ofleucaena management and benefits based on several commercial successes. Mimosine toxicity has not been a problem when cattle have access to tree …

Persistence Of Selected Tropical Legumes In Peninsular Florida (Usa) And The Guanacaste Province Of Costa Rica, W D. Pitman, A E. Kretscmer Jr, C G. Chambliss, N Leiva

IGC Proceedings (1977-2023)

Tropical legumes hold potential to contribute to pasture programs throughout tropical and subtropical America, even though there is currently limited use of these legumes. Several tropical legume accessions have been identified as adapted to the climatic and edaphic conditions of the wet-dry, low-fertility subtropical conditions of peninsular Florida and sites with similar soils and moisture in the extended Caribbean area. Plantings of these selected legumes were made to evaluate their persistence in grass swards under grazing. Legumes were seeded in rows in prepared seedbeds to allow establishment of the legumes along with the companion grass. One site in Guanacaste, Costa …

Sulfur Fertilization Of Five Tropical Forages Ii. Digestibility Of Dry Matter And Cell Wall Constituents, J E. Van Eys, S Ginting, H Pulungan, W L. Johnson

IGC Proceedings (1977-2023)

Four tropical grasses and one legume were fertilized with O or 60 kg S/ha. Leaves and stems of 6 and 9 weeks old regrowth were harvested seperately from replicated plots and used to study the effect of S fertilization on parameters of in vitro DM and NDF digestion. The overall effect of fertilization was negative and most pronounced for leaves. There were large differences among forages. DM digestibility at 48 h was reduced (P < .05) for fertilized guinea grass and setaria but NDF digestion at 96 h was only lower for guinea grass. DM digestibility of stems was not affected by fertilization but NDF disappearance of napier grass stems was decreased significantly. S fertilization had no effect on lag of NDF digestion but rate of NDF digestion for stems and leaves was reduced (P < .05) by fertilization. The effect was especially large for centro. It is suggested that the negative effects of S fertilization are associated with changes in the structural components of the forages and the source of the rumen inoculum.