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The Grassy Ticket in the Northern Part of China
No full textGrassy thicket is a main vegetation which is distributed in those provinces in the mountain-hilly region along the Qinling Mountain-Huai River and Great Wall, after the forests have been destroyed. The floristic composition of the grassy thicket community consists of 9-31 species. The dominant plants are grassy and mixed with shrubs. The major factor which affects the community is soil moisture content. The biomass of its fresh weight above-ground is mean 102. 7Kg/mu; the stocking rate is mean 25 .38mu/sheep/year. Under a well covered grassy thicket, the mould of soil-water erosion is 2700t/Km2, whereas when the plant community is destroyed it increases to 8640 t/Km2. When the hillside is closed to facilitate afforestation and the site quality is good, shrubs grow higher and dominate, while broadleaf deciduous young trees also exist. If we protect it, the grassy thicket should be succeeded by forest. The grassy thicket, if used as pasture land, would result in low productivity and would cause soil and water erosion, but it can control soil-water erosion and improve the environment; therefore, ecological considerations are very important in the utilization of grassy thicket
The Effects of Deep Incorporation of Sewage Sludge and/or Limestone on the Physical and Chemical Properties of Acid Gob for Revegetation of Grasses
No full textIt is very difficult to establish and maintain vegetation on acid gob ( the coarse waste materials resulting from washing coal) sites. A study was conducted to determine the effects of varying rates of sewage sludge and/or limestone incorporated to 30 and 60 cm depths on the physical and chemical properties of gob for the establishment of grasses. The experimental site was located at Peabody Coal Company\u27s Will Scarlet mine, Williamson County, Illinois, USA. The incorporation of sewage sludge as an amendment to acidic, low fertility and droughty gob resulted in favorable increases in organic matter, pH and reduced bulk density. The sludge amended gob was higher in heavy metals than the suggested maximum soil levels. Deep incorporation of limestone increased the soil pH sufficiently for good grass establishment and maintenance. The available soil moisture was not appreciably affected by the sludge treatments. After three years of study, the deep incorporation of sewage sludge and/or limestone appears to be a feasible method for vegetating acid gob sites without adding a soil cover
Studies on Dry Matter Production of Bahiagrass (Paspalum notatum) Sward I. Characteristics of Dry Matter Production during the Regrowth Period
No full textThis investigation was carried out to elucidate the characteristics of dry matter production during the regrowth period of bahiagrass (Paspalum notatum Flugge) sward. Growth analysis was periodically done throughout the regrowth period based on total dry weight and leaf area index. Total and top dry weight increased showing a typical sigmoid curve from July 27 to September 11. Produced dry weight and average crop growth rate during the regrowth period were 983 gDW/m2 and 21.3 gDW/m2/day, respectively. The harvest index on September 11 was 45.4%. Leaf area index also increased showing the sigmoid curve during the regrowth. Maximum leaf area was 8. 53 on September 11. The optimum leaf area index and maximum crop growth rate during the regrowth period were 5.5 and 30 gDW/m2/day, respectively. Net assimilation rate decreased linearly with increasing of leaf area index and average net assimilation rate throughout whole regrowth period was 4.48 gDW/m2/day. Further, productive structure of canopy in this grass sward showed a typical erect-leaved type and light extinction coefficient of the canopy was 0.36
Regrowth Ability of Napiergrass (Pennisteum purpureum Schamach) in the Dry, Cold Season in Taiwan
No full textThree varieties of napier grasses, A146, 7001 and 7007 were propagated with two-node stem cuttings in 50 cm x 100 cm population density in the field on 13th of Sept. 1983, to compare the regrowth ability of these grasses under the dry and cold season in southern Taiwan and to select a better one for recommendation in this area. Some parameters of growth analysis, the Leaf Area Index (LAI), Leaf Area Ratio (LAR), Net Assimilate Rate (NAR), Crop Growth Rate (CGR) and Relative Growth Rate (RGR) of the grasses were traced every 2 weeks after the cutting. LAI increased with the growing days in the regrowth process. On the contrary, the LAR was hightest in the early regrowth stage and declined as growth stage advanced. It was thought that the regrowth of the napier grass was the enlargement of leaf area in the early stage and was accompanied by the dry mater accumulation in the later stage. Change of NAR, CGR and RGR took the same course, raised from the early growth stage to the harvest, with the exception of a sharp decline in them on 13th March 1984, which was due to the sudden drop of the air temperature, the decrease in these parameters was greater in varieties 7001 and 7007 than in A146. It was suggested that variety A146 is more resistant to the lower temperature in regrowth process under the dry and cold season. It was recommendated that A146 is a better variety under dry, cold season and 70 days regrowing period is an appropriate time for the harvest in the winter growing season
The Effect of Row Width and Intrarow Spacing on the Productivity and Nutritional Quality of Silage Corn
No full textThis study was conducted to determine the effect of planting density on silage corn production and silage quality. Dent corn cv. Pioneer 3424 was planted at different or the same densities by changing row width or intrarow spacing or the both. The dry matter yield and silage quality were determined at different stages of ripening and the results are summarized as follows: When intrarow spacing was changed (under different intrarow spacings), the rate of increase of dry matter per plant was high at the low and intermediate planting densities and the dry matter yield per 10 are was high at the intermadiate planting density. When both the row width and intrarow spacing were changed to give different densities, the dry matter yield at the yellow-ripe stage was definitely high at the intermediate density. The ratio of ear dry matter to total dry matter observed at the intermediate planting density was essentially the same to that obtained at low planting density when the densities were adjusted by changing the intrarow spacing. The silage quality was excellent in most cases irrespective of planting densities. The digestible crude protein (DCP) and total digestible nutrients (TDN) were significantly lower at the high planting density than those at other densities. Both the DCP and TDN yields per 10 are were higher at low and intermediate densities. TDN yield was highest when planted at a 80 X 15 cm density. These results indicate that, when planting densities were adjusted by changing the row width and/or intrarow spacing, low and intermediate planting densities were favorable for silage corn to produce higher dry matter and nutritional quality
Sulfur Fertilization of Five Tropical Forages I. Dry Matter Production and Chemical Composition
No full textFour tropical grasses and one legume were grown on an oxic dystropept soil in W. Java, Indonesia. Two levels of S fertilizer were applied (0 and 60 kg S/ha). Forages were harvested at 6 and 9 week intervals during the wet and dry monsoons respectively. Production of leaves and stems was determined separately and samples of a 6- and 9-week regrowth were analyzed for chemical composition. The effect of S fertilization on dry matter (DM) yield was markedly influenced by the effect of season. During the wet season only the production of stems from napier grass was increased (P \u3c .05). During the dry season stem and leaf production of napier grass and centro increased (P \u3c .05) under fertilization but there was a decrease (P \u3c .05) in leaf production of guinea grass. S fertilization increased S content in leaves and stems by 23%. There was a tendency for N to increase and for NDF in leaves to decrease. Only in centro was ADF and lignin of fertilized plants lower (P \u3c .05). Although Ca, P, Mg, Cu and Zn were not affected by fertilization, ash content in leaves of fertilized forages differed (P \u3c .05) from controls
Leucaena - A Permanent Dry Season Forage in Australia
No full textLeucaena (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 leucaena and adequate grass. Tree leucaena exploits soil moisture and nutrients beyond the reach of grasses. Hence leucaena offers high quality green forage when tropical grasses are not growing due to cool conditions or soil moisture limitations. The use of leucaena during the nutritional stress period April-October each year has transformed beef breeding ranches into breeding and fattening enterprises. In addition the total number of cattle maintained on the ranch can be increased markedly. The commercial success of dryland tree leucaena pastures in central Queensland is encouraging rapid adoption, and interest has been generated in similar environments in tropical and sub-tropical Australia and other countries
Snow Damage to Pasture Fences in the Highland of Tohoku District of Japan
No full textSince 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 weight above 22 g/m2) with2 tensile strength 42 kgf/mm and #16 barbed wire (zinc coating weight above 200 g/m ) with tensile strength 125 kgf/mm . The rate of defects of posts, which were tipped, slanted, sunk into the ground groggy and bent, was 22.0% of all posts in spite of placing the props. In particular, the rate of that was increased as the topographical slant became steep. 3 ways of fixing the fallen wire to the posts were found. They were by using the plates, binding them with short wire and hanging them on the hooks of the posts. The way of repairing the slackned wire by using a cutting plier was 18.2% of all wire spans in 4-wire, particularly found frequently in the upper wire. From these surveys, the structural defects of the fences must be occured by the snow settling load. The rust was found on the surface of #14 barbed wire, coating a little zinc weight, except for the posts, props and #16 barbed wire. The broken wire was found largely in the second and third wire from the top wire rather than in the top or bottom wire, The percentage of broken #14 wire was double the average of that of #16 wire, and then about 75% of all broken wire occured within 20 cm distance from the post. From these observations, it is concluded that the breaking of the wire was caused not only by the heavier snow settling load and the smaller tensile strength of the wire but also by the worse way of repairing the fallen or slackened wire
Preliminary Fertilizer Requirements for Establishing Legume Based Pastures in the Alpine ZOone of Yunnan
No full textPreliminary 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 fertilizer recommendations of light to heavy rates of the locally manufactured fused calcium magnesium phosphatic fertilizer are presented which take the catenary position of the landscape and soil chemistry into consideration. Sulphate of potash (S and K} may be required additionally where soils are more leached and it appears that boron and molybdenum should be applied too with the recommended fertilizer but more experiments are needed to precisely define their rates of application. Depressions to the use of lime in the field trials, especially when using the cheaper local quicklime (CaO) may be caused by either alkali burning of the seedlings or through intensification of the boron deficiency
La Prairie Dans ses Usages Multiples: Conservation des Sols, Protection de L\u27Environnement, Etc.
No full textLes 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\u27exercent sur ces espaces. Ces facteurs ont engendre des transformations du milieu nature] permettant d\u27intensifier, et :i ]\u27extreme, de contr61er la production vegetale de ces ecosystemes. Si le role premier de ces formations herbacees a ete d\u27alimenter Jes herbivores afin que l\u27homme en obtienne une production (viande, lait, peaux, etc.), Jes autres fonctions de ces espaces ont une importance que !\u27on ne peut se permettre de negliger, que ce soit dans Jes zones fragiles (zone mediterraneenne, zones sub-arides, pentes des montagnes seches) ou dans Jes zones temperees. Afin de preserver - ou de creer - plusieurs fonctions simultanement compatibles, la gestion de ces espaces est une des voies de la recherche sur la « prairie » qui a ete abordee dans la section 14. Lutte contre ]\u27erosion et amelioration de la production fourragere; production ligneuse, amelioration du convert herbace et piiturage en foret ; paturage, preservation de la faune sauvage et tourisme dans Jes pares nationaux; piiturage et effets des epandages de lisiers, de boues d\u27epandage ou de dechets de !\u27exploitation des phosphates sur !es prairies sont quelques-uns des themes de recherche presentes par !es participants