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Carbohydrate Reserves Of Perennial Grasses: Effect Of Drought And Defoliation Intensity, S P. Boschma, M J. Hill, J M. Scott, J J. Lutton Jun 2024

Carbohydrate Reserves Of Perennial Grasses: Effect Of Drought And Defoliation Intensity, S P. Boschma, M J. Hill, J M. Scott, J J. Lutton

IGC Proceedings (1977-2023)

The carbohydrate reserves of six perennial grasses were measured during exposure to drought and defoliation over spring-summer and summer-autumn seasons. Of the six species assessed, tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) had the highest level of reserves while wallaby grass (Danthonia richardsonii) had the lowest levels. The results indicate that during the spring-summer period drought intensity had a greater effect on plant reserves than defoliation intensity. However, defoliation had a greater effect on reserves during the summer-autumn period. It is suggested that tiller reserves may be most affected when drought is …


Tiller Dynamic Of Dwarf Elephantgrass (Pennisetum Purpureum Cv. Mott) Under Defoliation, T Clavero Jun 2024

Tiller Dynamic Of Dwarf Elephantgrass (Pennisetum Purpureum Cv. Mott) Under Defoliation, T Clavero

IGC Proceedings (1977-2023)

A field study was conducted at the Animal Production Research Center of the University of Zulia, Venezuela. The objective of this experiment was to evaluate the tiller dynamic of dwarf elephantgrass (Pennisetum purpureum cv. Mott) under three cutting frequencies (CF) 28, 42 and 56 days and three cutting heights (CH) 10, 20 and 40 cm in order to estimate basal (BT), aerial (AT) and dead tillers (DT). The experiment was laid out as a split-plot trial with three replications. The number of basal tillers increased as CF was shortened and CH was increased. The intensity of defoliation independent of CF …


Animal Productivity And Dynamics Of Native Pastures Improved With Oversown Legumes In Uruguay, D F. Risso, E J. Berretta Jun 2024

Animal Productivity And Dynamics Of Native Pastures Improved With Oversown Legumes In Uruguay, D F. Risso, E J. Berretta

IGC Proceedings (1977-2023)

Natural pastures in large areas of Uruguay can be improved by fertilization with phosphorus (P) and surface sowing of adapted legumes, promoting an increased forage production and quality, with the consequent higher carrying capacity and better animal performance. A study was conducted to evaluate two improved grasslands with two stocking rates under rotational grazing. Such improvements resulted from the oversowing of: 1) white clover (Trifolium repens) plus birdsfoot trefoil (Lotus corniculatus); and 2) annual lotus (Lotus subbiflorus). In these pastures, with important presence of legumes, a higher frequency of C3 and winter species, high levels …


Yield And Quality Of Cereal And Cereal-Pea Companion Crops And Their Effect On Alfalfa Establishment, J E. Johnston Jun 2024

Yield And Quality Of Cereal And Cereal-Pea Companion Crops And Their Effect On Alfalfa Establishment, J E. Johnston

IGC Proceedings (1977-2023)

This study was carried out to determine the effect of management practices (harvest maturity, cereal species, mixtures with field peas (Pisum sativum)) on the yield and quality of cereal companion crops harvested for forage and the impact of those practices on subsequent alfalfa (Medicago sativa) yields. Replicated factorial experiments were conducted at three locations in northern Ontario from 1993 to 1995. Companion crop forage yields were increased and quality decreased by harvesting as the heads emerged as compared to the late boot stage. Triticale (X Triticosecale) was lower yielding than either oats (Avena sativa) …


The Effect Of Different Oversown Legume Species And Row Spacings Upon The Production Of Degraded Cultivated Pastures, M R. Colabelli, A Mazzanti Jun 2024

The Effect Of Different Oversown Legume Species And Row Spacings Upon The Production Of Degraded Cultivated Pastures, M R. Colabelli, A Mazzanti

IGC Proceedings (1977-2023)

The establishment and growth of three leguminous plants Medicago sativa (A), Trifolium pratense (TR) and Lotus corniculatus (LC) was analysed. They were oversown on three different row spacings (10, 20 y 40 cm) on September 12, 1994. Density was estimated by marking and sequential counting of seedlings. Growth was estimated from Leaf Area Index (LAI) and from forage accumulation per area unit on three dates: D1 = 26/01/95; D2 = 11/04/95; D3 = 5/12/95. Total forage accumulation was higher (p<0.05) for the treatments oversown with TR in D1 at the smaller distances (average from 10 and 20 cm, 4130 kg DM/ha, 46% higher than treatment control (C); all the other treatments did not differ from C). In D2 there were no differences between treatments (average 1995 kg DM/ha); in D3 there were no differences among the oversown treatments (average 2498 kg DM/ha) and forage accumulation was 59% higher than C. There was no difference in seedling density between oversown legumes A and TR but both were higher (p<0.05) than that of LC. The relationship between the LAI of the oversown legume and that of the vegetation present was higher (p<0.05) for TR than for the rest of the treatments: D1, TR=1.43, A=0.21, LC=0.1; D2, TR=1.62, A=0.31, LC=0.2 and D3, TR=1.91, A=0.86, LC=1.05 . It is concluded that it is feasible to increase yield and modify botanical composition of degraded pastures by oversowing legumes.


Effects Of Seasonal Cutting Regimes On The Dm Yield Of Temperate Pastures. Ii. Response To Frequency Of Defoliation Of A Five-Year Old Sown Pasture, E A. Moliterno, R A. Zanoniani Jun 2024

Effects Of Seasonal Cutting Regimes On The Dm Yield Of Temperate Pastures. Ii. Response To Frequency Of Defoliation Of A Five-Year Old Sown Pasture, E A. Moliterno, R A. Zanoniani

IGC Proceedings (1977-2023)

The effects of three frequencies (15; 30 and 45 days) of defoliation were assessed on a five-year-old temperate pasture composed of tall fescue (Festuca arundinacea Schreb.), white clover (Trifolium repens L.) and birdsfoot trefoil (Lotus corniculatus). Total annual DM yield showed a significant lower production for the most frequent defoliation management, 30 and 45 days frequency treatments averaging 32% more forage production with no statistical difference between them. Spring was the only season in which the more lenient defoliation significantly outyielded the 15- day interval treatment, which made up for the annual difference recorded. Through the …


Effects Of Seasonal Cutting Regimes On The Dm Yield Of Temperate Pastures. I. Response Of A Second-Year Sown Pasture, E A. Moliterno, R A. Zanoniani, C Tafernaberry Jun 2024

Effects Of Seasonal Cutting Regimes On The Dm Yield Of Temperate Pastures. I. Response Of A Second-Year Sown Pasture, E A. Moliterno, R A. Zanoniani, C Tafernaberry

IGC Proceedings (1977-2023)

The effects of combined frequencies and intensities of defoliation were assessed through different sward heights at cutting time and residual stubble heights on a second-year temperate pasture composed of tall fescue (Festuca arundinacea Schreb.), white clover (Trifolium repens L.) and birdsfoot trefoil (Lotus corniculatus). Frequencies of defoliation could only be evaluated in autumn and winter since soil water deficit became especially critical in spring and summer. Main differences in yield within seasons were due to a combination of the intensity of defoliation at which the particular treatment was managed and that of the previous season. …


Sward Structure Change And Production Increases Following Spring Grazing Management, A Hernandez Garay, J Hodgson, C Matthew Jun 2024

Sward Structure Change And Production Increases Following Spring Grazing Management, A Hernandez Garay, J Hodgson, C Matthew

IGC Proceedings (1977-2023)

The objective of this experiment was to study sward structure effects on production of perennial ryegrass-white clover swards with and without white clover following lax spring grazing periods of different duration. Two periods of 6 (short release - SR) and 12 (long release - LR -) weeks of lax grazing were compared against a conventional hard grazing throughout (early control - EC). Treatments were arranged in a factorial design with 3 replicates. Changes in sward structure were reflected in herbage production before (spring) and after the control period (summer-autumn). During spring, herbage mass was increased as a consequence of an …


Overgrazing Impact Upon Rangeland Ecosystems Of Kazakstan Deserts, K Karibayeva Jun 2024

Overgrazing Impact Upon Rangeland Ecosystems Of Kazakstan Deserts, K Karibayeva

IGC Proceedings (1977-2023)

Vegetation dynamics trends are studies in connection with natural and human-induced factors. Interrelation of rangeland ecosystems with climate and grazing type is revealed. Degression, demutation and dynamics regulation diagrams are given for different conditions of use. Some quantitative and qualitative criteria were elaborated for rangeland ecosystems assessment. Ecosystem degradation indicators were identified, methods were elaborated for making subject maps for environmental assessment and sustainable management of grasslands. A method of seasonal cartographic rangeland cadastre was elaborated by the example of Volga - Ural sands on the basis of the map (S. 1:500,000)


Productivity Of Pasture Consisting Of Both Unimproved And Improved Areas In Aso Region Of Kyushu District, C Okamoto, K Kabata, K Tsuji, M Kikuchi Jun 2024

Productivity Of Pasture Consisting Of Both Unimproved And Improved Areas In Aso Region Of Kyushu District, C Okamoto, K Kabata, K Tsuji, M Kikuchi

IGC Proceedings (1977-2023)

Productivity of pasture consisting of both unimproved and improved areas was investigated in terms of conversion efficiency of solar energy into products and nutrient intake of animal. It was shown that animal production is mainly supported by the improved area in spring and late-autumn while the production is supported together by both areas in summer by reasons of increases in productivity of the unimproved area and productive depression in the improved area. CP/DE balance of grazed herbage was close to the requirement ofthe animal in the case where the unimproved area was grazed with the improved area rather than in …


Grassland Productivity In The Indian Himalaya And Performance Of Introduced Temperate Forage Species In Cold And Semi-Arid Environment, J R. Sharma, A N. Ghosh Jun 2024

Grassland Productivity In The Indian Himalaya And Performance Of Introduced Temperate Forage Species In Cold And Semi-Arid Environment, J R. Sharma, A N. Ghosh

IGC Proceedings (1977-2023)

Grasslands in the Himalayan ranges, particularly in the middle altitudes, are over-exploited by both sedentary and nomadic flocks. No systematic studies have been made to assess the productivity and carrying capacity of these grasslands so that suitable improvement measures could be adopted. A study conducted in the Shimla district of Himachal Pradesh (HP) at 2092, 2400 and 2895 meters above mean sea level (amsl) and varying soil conditions, showed that protection alone increased dry matter production between 9 and 188% over a three year period and average production in the third year from lower to higher altitude grasslands was 101.1, …


Perception Of Rangeland By Herders In Northern Cameroon, E Tedonkeng Pamo, P Scholte Jun 2024

Perception Of Rangeland By Herders In Northern Cameroon, E Tedonkeng Pamo, P Scholte

IGC Proceedings (1977-2023)

Range scientists have always had the mistaken idea that herders cannot appraise, characterize or assess the state of their rangeland or range resource. From observations made in northern Cameroon, it appears that herders know the pastoral environment in which they operate probably better than many range scientists. They do not seem to have a good idea on range trends. However, from their pattern of range utilization over time it is possible to have an assessment of the state and trend of rangeland. A wide range of information on the pastoral knowledge of rangeland is needed to develop a sustained range …


Nutrient Content Of Saskatchewan Native Range Plants, Zoheir Abouguendia Jun 2024

Nutrient Content Of Saskatchewan Native Range Plants, Zoheir Abouguendia

IGC Proceedings (1977-2023)

This study reports on the nutrient content and digestibility of five cool-season grasses common in the Mixed-Prairie Ecoregion of Saskatchewan, Canada: (1) green needlegrass (Stipa viridula Trin.); (2) needle-and-thread (Stipa comata Trin & Rupr.); (3) western porcupinegrass (Stipa curtiseta (Hitchc.) Backworth); (4) northern wheatgrass (Agropyron dasystachyum (Hook.) Scribn.); and (5) western wheatgrass (Agropyron smithii Rydb.). Plant material was collected monthly and analyzed for invitro organic matter digestibility ( IVOMD), crude protein (CP), P, Ca, ADF and NDF. All species showed similar intra-seasonal pattern in the various parameters studied and no species x month interactions were …


Negative Hypergeometric Series And Taylor's Power Law In Occurrence Of Plant Populations In Semi-Natural Grassland In Japan, M Shiyomi, T Egawa, Y Yamamoto Jun 2024

Negative Hypergeometric Series And Taylor's Power Law In Occurrence Of Plant Populations In Semi-Natural Grassland In Japan, M Shiyomi, T Egawa, Y Yamamoto

IGC Proceedings (1977-2023)

Attempts were made to determine whether the spatial distribution of the plant species composing vegetation of a semi-natural grassland is heterogeneous, using negative hypergeometric series (NHG) and Taylor’s power law (TPL). The occurrence of each species was observed, in an area of the grasslands, using 100 quadrats with a size of 50 cm x 50 cm, each of which was divided into 4 small quadrats with an area of 25 cm x 25 cm. For all species dominating in the grassland, good fits to the NHG and TPL were obtained. Species which grow stolons, rhizomes and tillers for propagation such …


Recultivation And Revitalization Of Karst's Regions With Sheep And Goats As A Tool, M Pogacnik, P Juntes, D Kompan, T Vidrih, M Kotar Jun 2024

Recultivation And Revitalization Of Karst's Regions With Sheep And Goats As A Tool, M Pogacnik, P Juntes, D Kompan, T Vidrih, M Kotar

IGC Proceedings (1977-2023)

The main goal of our project is to revitalize abandoned karstic regions on the principles of silvopastoral systems based on traditional husbandry of goats and sheep and by causing minimal disturbances to the nature. Results of our two year experiment show positive effects on land cleaning and quantity and quality of the turf. However, restriction of animals to a fenced area, where the feed is of a lesser quality also has negative effects on the animals.


Introduction Of White Clover In Native Grasslands Of Bhutan-Impact, Potential, And Problems, W Roder, K Wangdi, P Gyamtsho Jun 2024

Introduction Of White Clover In Native Grasslands Of Bhutan-Impact, Potential, And Problems, W Roder, K Wangdi, P Gyamtsho

IGC Proceedings (1977-2023)

Important genera of native grass species common to the grasslands of Bhutan include: Schizachyrium, Arundinella, Agropyron, Agrostis, Bromus, and Helictorichon. White clover was first introduced to the country in 1970. White clover introduction and application of P increased dry matter production of native grasslands from <2 t ha-1 to >10 t ha-1. In the elevation range ,2000-3500 m white clover is the best fodder species for improving existing grassland. Fast expansion of the species through adoption by farmers spreading by grazing animals has caused some panic and demands for a reassessment of its potential.


Animal-Plant Interactions In An Atriplex Canescens Dominant Community Browsed By Cattle, A F. Cibils, D M. Swift, R H. Hart Jun 2024

Animal-Plant Interactions In An Atriplex Canescens Dominant Community Browsed By Cattle, A F. Cibils, D M. Swift, R H. Hart

IGC Proceedings (1977-2023)

Atriplex canescens is a relatively widespread shrub in rangelands of the western United States,with a longstanding reputation as a valuable browse resource for ruminants. The breeding system of tetraploid populations has been extensively studied both in common gardens and in natural populations. However, browser-driven alterations of shrub sex ratios, and the probable mechanisms involved in such processes, have received relatively little attention in these populations. We report results from a preliminary study conducted in a stand of A. canescens at a site on the shortgrass steppe. Numbers of young shrubs decreased with increasing shrub density. Sex ratios did not differ …


An Examination Of Dry Weight Rank And Comparative Yield Techniques For Grasslands Production Estimation, H Arzani, G W. King Jun 2024

An Examination Of Dry Weight Rank And Comparative Yield Techniques For Grasslands Production Estimation, H Arzani, G W. King

IGC Proceedings (1977-2023)

Currently used method of dry matter yield estimation was tested compared with yield estimation from cover measurement using clipped data as an index. The dry weight rank (DWR) method was able to show variations within and between sites in different seasonal conditions. However it was less accurate than other techniques and possibly subject to personal bias.


Application Of Remote Sensing (Landsat Tm Data) For Vegetation Parameters Measurement In Western Divisions Of Nsw, H Arzani, G W. King Jun 2024

Application Of Remote Sensing (Landsat Tm Data) For Vegetation Parameters Measurement In Western Divisions Of Nsw, H Arzani, G W. King

IGC Proceedings (1977-2023)

The capability of Landsat (TM) data for vegetation parameters estimation was examined. Suitable vegetation indices were selected for arid and semi-arid areas. The possibility of accurate estimation of cover and yield of group of species was found.


Effect Of Nitrogen On The Reserve Nutrients Of Rhizomes And Their Relation To Shoot Regrowth In Miscanthus Floridulus, Y C. Wang, M L. Lee Jun 2024

Effect Of Nitrogen On The Reserve Nutrients Of Rhizomes And Their Relation To Shoot Regrowth In Miscanthus Floridulus, Y C. Wang, M L. Lee

IGC Proceedings (1977-2023)

A 3-week-treatment of nitrogen dressings and of shoot cuttings were conducted on Miscanthus floridulus before the harvest. The nitrogen dressing increased the fresh weight and dry matter of the plants, but did not increase the plant height and shoot number. The reserved nutrients, especially the sugars and starch in the rhizomes were decreased by the cut treatments. Crude protein in the rhizomes was increased with the nitrogen amounts applied, though the carbohydrates were decreased. The decrease in reserved nutrients caused the growth inhibition of new shoots, and the more the reserved nutrients decreased the more severely was the growth inhibited. …


Improvement Of Subtropical Native Grasslands With The Introduction Of Forage Species And Phosphorous Fertilizers, M N. Baby, S.B C. Lustosa, A Moraes, A.C V. Motta, R L. Stanger Jun 2024

Improvement Of Subtropical Native Grasslands With The Introduction Of Forage Species And Phosphorous Fertilizers, M N. Baby, S.B C. Lustosa, A Moraes, A.C V. Motta, R L. Stanger

IGC Proceedings (1977-2023)

The experiment took place in Guarapuava-Brazil, from May 1994 to January, 1996 to evaluate the improvement of a subtropical native grassland by the introduction of species and phosphate fertilization. It was observed that for the higher dose applied there occurred an increase over the production of dry matter and crude protein production and absorption of P and K in the plant. A response was not found to the 180 kg P2O5/ha application probably because of the high capacity of soil adsorption, the method of fertilizer application, non favorable climatic conditions and liming interference. The single superphosphate-SS application was superior to …


Manipulation Of Botanical Composition Of Native Pastures By Grazing In Temperate South-East Australia, D L. Garden, D A. Friend, P M. Dowling, G M. Lodge Jun 2024

Manipulation Of Botanical Composition Of Native Pastures By Grazing In Temperate South-East Australia, D L. Garden, D A. Friend, P M. Dowling, G M. Lodge

IGC Proceedings (1977-2023)

Historical evidence indicates that substantial changes have occurred in the botanical composition of native pastures in temperate southeast Australia as a result of grazing by sheep and cattle. However, the resulting pastures now appear to be relatively stable and there has been limited success in changing composition experimentally. This paper reports the results of experiments conducted at four locations in south-east Australia designed to increase the proportion of desirable species in native pastures by grazing management.


Production, Stability And Biodiversity Of North Island New Zealand Kill Pastures, P K. Nicholass, P D. Kemp, D J. Barker, J L. Brock, D A. Grant Jun 2024

Production, Stability And Biodiversity Of North Island New Zealand Kill Pastures, P K. Nicholass, P D. Kemp, D J. Barker, J L. Brock, D A. Grant

IGC Proceedings (1977-2023)

The relationship between pasture biomass and pasture stability with species diversity was derived for two low fertility, hill land sites. At one site, pasture production increased with an increased number of species contributing to biomass. The coefficient of variation in biomass, however, decreased with higher numbers of species. At a second site, pasture biomass was also found to increase with increasing species diversity, but the relationship between yield stability and species diversity was not as strong as at the first site. This suggested there were other factors that influenced the stability of pastures, which could include the substitution effect between …


Disturbance By Mechanical Phosphorous Fertilization On The Cover And Biomass Of Humid Alkaline Communities Of The Flooding Pampa (Argentina), O E. Ansin, E M. Oyhamburu, J L. Delgado Caffe Jun 2024

Disturbance By Mechanical Phosphorous Fertilization On The Cover And Biomass Of Humid Alkaline Communities Of The Flooding Pampa (Argentina), O E. Ansin, E M. Oyhamburu, J L. Delgado Caffe

IGC Proceedings (1977-2023)

Experiments were carried out in order to evaluate the impact of mechanical perturbations, phosphorous fertilization and grazing on the native grasslands. Six treatments were tested: three without grazing and three subjected to grazing. Both situations were plowed, plowed plus fertilization or kept untreated. During the study botanical composition, vegetative cover, species diversity and above ground biomass were measured. Plowed and plowed plus fertilization treatments drastically reduce all of these parameters related to community structure and forage production. These figures contrasted with the non-perturbated treatments, were values did not change significantly from the original state. Mechanical perturbations provoked reductions on grassland …


Sustainability Of Management Practices Of Mountain Pastures In Reunion Island (Indian Ocean), V Blanfort, P Thomas, G Balent, A Michon Jun 2024

Sustainability Of Management Practices Of Mountain Pastures In Reunion Island (Indian Ocean), V Blanfort, P Thomas, G Balent, A Michon

IGC Proceedings (1977-2023)

The grazing systems are an essential component of these volcanic highlands (1000-2000m). Our investigations consist of building up diagnosis tools and decision rules for a sustainable control of these fragile grazed ecosystems composed of native and sown pastures. The use of a systemic approach allows us to analyse the interrelationship between the vegetation dynamic and the agricultural practices through three biological indicators which relate to one hundred paddocks in six cattle farms. Concerning the vegetation dynamics, it seems that some management practices lead to a nonreversable degradation stage. As regards the forage system, the measure of sward-height and estimation of …


Restoration Of Degraded Coastal Grasslands In The Falkland Island, J A. Kerr Jun 2024

Restoration Of Degraded Coastal Grasslands In The Falkland Island, J A. Kerr

IGC Proceedings (1977-2023)

In the Falkland Islands the coastal grasslands are the most valuable for wool production and important habitats for wildlife. Tussac grass (Parodiochloa flabellata Lam.) and sandy areas which support an Ammophilia - Elymus association have been degraded by overgrazing, burning and invasion by alien flora and fauna. Traditional approaches to restoration, mainly by replanting, have had limited success. Research on


Proximity Of Water Affects Grazing Distribution And Soil Nutrient Cycling, J R. Gerrish, P R. Peterson, F A. Martz Jun 2024

Proximity Of Water Affects Grazing Distribution And Soil Nutrient Cycling, J R. Gerrish, P R. Peterson, F A. Martz

IGC Proceedings (1977-2023)

A three-year study was conducted to quantify the effects of travel distance to water on pasture utilization rate and soil nutrient gradients. A 64 ha unit was divided into 16 4 ha pastures having maximum travel distances ranging from 250 to 450 m. Temporal utilization rate (UR) and soil nutrient levels were determined at 30 m intervals beginning at the water source. Temporal UR significantly declined beyond 250 m in all pastures having travel distances exceeding 250 m while pastures with less than 250 m travel distance were uniformly grazed. Increased nutrient level gradients beginning within 60 m of water …


Grasslands As A Comparative For Farming Practices' Influence On Carbon/Nitrogen Dynamics, S A. Clancy, M E. Biondini, J C. Gardner Jun 2024

Grasslands As A Comparative For Farming Practices' Influence On Carbon/Nitrogen Dynamics, S A. Clancy, M E. Biondini, J C. Gardner

IGC Proceedings (1977-2023)

A remnant prairie was used for comparison of the soil as a natural resource among alternative and conventional farming systems. Beginning and ending biotic and abiotic characteristics were quantified directly. Carbon and N flow was calculated using CENTURY model. Carbon decay was not tied to the size of the soil organic matter pool (SOM), but to crop choice. Nitrogen decay was linked to the size of the SOM pool. Nitrogen fertilizer depressed the amount of N mineralized by soil biota. The alternative farming systems in North Dakota (no-till and green-manure fallow) more nearly mimic the ecosystem processes of the prairie …


Nutrient Cycling For Pasture Fertilization Management Of Dairy Farms In The Basque Country (Northern Spain), M Oyanarte, M Rodriguez, G Besga, M Domingo Jun 2024

Nutrient Cycling For Pasture Fertilization Management Of Dairy Farms In The Basque Country (Northern Spain), M Oyanarte, M Rodriguez, G Besga, M Domingo

IGC Proceedings (1977-2023)

The implementation of the European Agricultural Policy implies a new orientation for the management of dairy farms and, as a result, of pasture fertilization. It is important to develop a new methodology for the calculation of fertilizer recommendations. In order to do this, a model based on P and K nutrient cycles has been used and a computer program has been developed to calculate these cycles and estimate the following parameters: potential pasture yield, yield at the different cuttings, efficiency of excreta recycling in the pasture and efficiency of grass utilization, all these parameters being necessary for the calculation of …


Nitrogen Cycling In A Ley-Dominated Production System, B Fagerberg Jun 2024

Nitrogen Cycling In A Ley-Dominated Production System, B Fagerberg

IGC Proceedings (1977-2023)

N balance in a full-scale experiment with conventional and ecological farming systems at Öjebyn in northern Sweden was calculated with a nutrient flow model. Due to increased milk production there was a yearly increase in both N-input and output. Nfixation was on average twice as large in the ecological system. The farm N balance was increasingly positive in the conventional system and negative in the ecological. The soil N balance was more negative in the ecological system and less positive in the conventional system. Conclusions are: (1) ecological farming is possible without immediate DM yield reductions, but with negative effects …