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Articles 1951 - 1980 of 12002

Full-Text Articles in Physical Sciences and Mathematics

Agronomic Characterisation Of Sewage Sludge: Residual Effects, M. R. Mosquera-Losada, A. Rigueiro-Rodríguez Aug 2023

Agronomic Characterisation Of Sewage Sludge: Residual Effects, M. R. Mosquera-Losada, A. Rigueiro-Rodríguez

IGC Proceedings (1993-2023)

The progressive implementation of the EU Urban Waste Water Treatment Directive 91/271/EEC is increasing the quantities of sewage sludge requiring disposal. Agronomic use of sewage sludge should be based on crop fertiliser requirements and heavy metals content. Sewage sludge fertiliser potential depends on the stabilisation treatments of sewage sludge: composting, anaerobic digestion, aerobic digestion or pelleting (EPA, 1994). The objective of this experiment was to evaluate the fertiliser effectiveness and residual effects of three types of sewage sludge treated in three different ways.


Increase In Forage Maize Production By Bacterial Fertilisers, D. Egamberdiyeva, G. Hoflich Aug 2023

Increase In Forage Maize Production By Bacterial Fertilisers, D. Egamberdiyeva, G. Hoflich

IGC Proceedings (1993-2023)

Farmers in many countries value green material generated from maize as a high quality forage. Its inclusion in dairy cow diets can improve forage intake, increase animal performance and has the potential to reduce production costs (Phipps, 1994). Restrictions on the use of chemical fertilisers and a renewed interest in organic sustainable farming systems in general, has restored attention to crop rotations The increase of maize production using bacterial fertilisers also gives alternative ways to reduce chemical fertilisers in forage production. Increased uptake of nutrients such as N, P, and K and crop yield was reported with rhizobacteria (Lazarovits & …


Soil Organic Matter Along A Degradation Gradient In A Semi-Arid Rangeland Of South Africa, Chris C. Du Preez, Hennie A. Snyman Aug 2023

Soil Organic Matter Along A Degradation Gradient In A Semi-Arid Rangeland Of South Africa, Chris C. Du Preez, Hennie A. Snyman

IGC Proceedings (1993-2023)

In a semi-arid South Africa rangeland on a sandy loam soil, artificial manipulations to create various rangeland conditions typical of different levels of livestock impact were shown to result in considerable losses of organic matter after 15 years (Du Preez & Snyman, 1993). In this follow-up study on a similar soil, we regularly measured the organic matter content following the conversion of rangeland in a good to a poor ecological condition, an undisturbed bare soil and a cultivated soil respectively. The changes in soil organic matter content after five years are reported.


Influence Of Grazing On Soil Microbial Communities On A Mixed Grass Prairie Ecosystem, L. J. Ingram, G. E. Schuman, P. D. Stahl, J. Buyer Aug 2023

Influence Of Grazing On Soil Microbial Communities On A Mixed Grass Prairie Ecosystem, L. J. Ingram, G. E. Schuman, P. D. Stahl, J. Buyer

IGC Proceedings (1993-2023)

The grazing of ungulates is the predominant use for much of the world's semiarid rangelands. Grazing these lands can result in significant changes not only in the vegetation community but also in the soil physical, chemical and biological properties. Changes in soil physical and chemical properties and the plant community can potentially lead to changes in soil microbial communities which may have long-term ramifications for nutrient cycling and carbon (C) sequestration. The objective of this research was to ascertain the influence of three long-term grazing treatments on soil microbial communities.


Soil Microbial Diversity Of An Artificial Caragana Korshinskii Plantation On The Loess Plateau Of China, W. Zhang, H. L. Wei, H. W. Gao, Y. G. Hu Aug 2023

Soil Microbial Diversity Of An Artificial Caragana Korshinskii Plantation On The Loess Plateau Of China, W. Zhang, H. L. Wei, H. W. Gao, Y. G. Hu

IGC Proceedings (1993-2023)

Peashrub (Caragana korshinskii) is an important dune-fixation plant on the loess plateau of China and is valuable in ecological environment construction of North-western China. For determining relationships between peashrub and soil microbes, three clone libraries of 16S rDNA from rhizoplane, rhizosphere and bulk soil communities of peashrub were constructed with a culture-independent approach. The data obtained from three clone libraries were used to investigate the magnitude of vegetative changes in the microbial community, and to search for general ecological relationships.


Soil Enzyme Activities As Bio Indicators Of Soil Ph And Fertility In Temperate Grassland, Iker Mijangos, A. Ibarra, Isabel Albizu, Sorkunde Mendarte, Carlos Garbisu Aug 2023

Soil Enzyme Activities As Bio Indicators Of Soil Ph And Fertility In Temperate Grassland, Iker Mijangos, A. Ibarra, Isabel Albizu, Sorkunde Mendarte, Carlos Garbisu

IGC Proceedings (1993-2023)

In recent years, biological indicators are being used to estimate the continued capacity of a given soil to function (i.e., soil health). After all, biological processes are intimately linked with the maintenance of soil structure and fertility, being more sensitive to changes in the soil than conventional physicochemical parameters. Soil enzymes, as mediators and catalysts of vital soil functions, offer great potential as integrative indicators of soil health (Dick et al., 1996). The main aim of the current work was to study the potential of soil enzyme activities as biological (more precisely, biochemical) indicators of soil physicochemical …


The Effect Of Nitrogen Fixation And Plant Species On Ammonium And Amino Acids Soil Contents, F. Lesuffleur, S. Diquélou, A. Bré, J. B. Cliquet Aug 2023

The Effect Of Nitrogen Fixation And Plant Species On Ammonium And Amino Acids Soil Contents, F. Lesuffleur, S. Diquélou, A. Bré, J. B. Cliquet

IGC Proceedings (1993-2023)

Grass and legume intercropping systems, particularly ryegrass-clover mixed cultures, increase grasslands productivity, due to the clover nitrogen (N) fixation and to the transfer of part it to the companion grass. The objective of this experiment was to determine if N fixation and plant species could modify ammonium and amino acids soil contents.


Soil Constraints (Ph And Aluminium) For Legume Performance In Hill Country Of Uruguay, Walter Ayala, R. E. Bermúdez Aug 2023

Soil Constraints (Ph And Aluminium) For Legume Performance In Hill Country Of Uruguay, Walter Ayala, R. E. Bermúdez

IGC Proceedings (1993-2023)

Pastoral areas in eastern Uruguay have soils with pH 5.5 or lower (Mas, 1978), which is frequently associated with the acid soil syndrome (Cregan, 1980). As pH drops below 5.5, aluminium (Al) concentration can increase to toxic levels. These conditions may adversely affect growth of introduced legumes. A way to overcome these constraints is by the use of tolerant species. The objective of this study was to evaluate the adaptation and productivity of different legumes under environments with restrictions in pH and Al concentrations.


Grazing Effects On Some Soil Characteristics In Lar Rangelands, S. A. Javadi, M. Jafari, Gh. Zahedi Aug 2023

Grazing Effects On Some Soil Characteristics In Lar Rangelands, S. A. Javadi, M. Jafari, Gh. Zahedi

IGC Proceedings (1993-2023)

Heavy grazing pressures jeopardise the sustainability of the ecosystem by reducing soil fertility (Dormaar et al., 1998). Different results have been reported of grazing intensities on soil chemical properties, which stem from climate, soil, vegetation, management and kind of animal (Dormaar et al., 1998; Javadi, 2003; Sanadgool, 2002).


Accumulation And Decomposition Rates And N, P And K Returned To The Soil By The Litter Of Tropical Legumes And Grasses, Gustavo Crespo, I. Rodríguez, M. F. Días, Sandra Lok Aug 2023

Accumulation And Decomposition Rates And N, P And K Returned To The Soil By The Litter Of Tropical Legumes And Grasses, Gustavo Crespo, I. Rodríguez, M. F. Días, Sandra Lok

IGC Proceedings (1993-2023)

The return of plant nutrients through litter decomposition of legumes and grasses is important for the sustainability of grassland ecosystems (Sánchez et al., 1989). Therefore, the selection of species that produce high amounts of decomposable litter is important . The objective of the present work was to study the production and decomposition rates of litter from various legumes and grasses in Cuba.


Effect Of Earthworm Manure Fertilisation On Biomass Production And Mineral Content Of Digitaria Swazilandensis, A. Paredes, S. Camacaro, W. Machado Aug 2023

Effect Of Earthworm Manure Fertilisation On Biomass Production And Mineral Content Of Digitaria Swazilandensis, A. Paredes, S. Camacaro, W. Machado

IGC Proceedings (1993-2023)

Chemical fertilisers are expensive and can cause environmental contamination, affecting the biodiversity; it is therefore desirable to use organic manure that is cheaper and can be prepared on the same farm. Earthworm manure is the product of worms that transform organic matter (Salinas & Rojas, 1995), which improves the physical, chemical and biological properties of the soil (Pérez, 1993; Ravera & De Sanso, 1999). The importance of these improvements justifies the use of the worm humus in fertilisation programs in grasslands. Therefore, the objective of this experiment was to evaluate the effect of the earthworm manure on the biomass production …


Fire And Nutrient Cycling In Shortgrass Steppe Of The Southern Great Plains, Usa, Paulette L. Ford, C. S. White Aug 2023

Fire And Nutrient Cycling In Shortgrass Steppe Of The Southern Great Plains, Usa, Paulette L. Ford, C. S. White

IGC Proceedings (1993-2023)

Fire in semi-arid grasslands releases nutrients bound up in organic matter and accelerates the rate of decomposition in the soil. This research experimentally tested effects of season and frequency of fire on nutrient cycling dynamics in shortgrass steppe. The objective was to identify if fire treatments have the ability to increase potential grassland productivity relative to untreated 'reference condition' grassland. Many such studies focus on short-term, direct effects of fire. However, this study is part of a long-term, 18-year study examining both direct, and indirect effects of fire in the growing vs. dormant season at return intervals of 3, 6 …


Soil Quality Under Permanent And Annual Pastures: Its Implications For Soil Microbial Activity And Nutrient Turnover, R. J. Haynes, R. M. Milne, N. Miles Aug 2023

Soil Quality Under Permanent And Annual Pastures: Its Implications For Soil Microbial Activity And Nutrient Turnover, R. J. Haynes, R. M. Milne, N. Miles

IGC Proceedings (1993-2023)

Dairy farming in humid, subtropical parts of South Africa is based on permanent kikuyu grass (Pennisetum clandestinum) swards. However, there is a shortage of feed during the winter because low temperatures limit kikuyu growth. As a result, annual pastures incorporating temperate grasses, are grown for winter feed production. The grasses used are typically annual ryegrass (Lolium multiflorum) and sometimes perennial ryegrass (Lolium perenne). Kikuyu is so invasive in the locality that it becomes dominant within a few years, even if the field is sown to perennial ryegrass. For that reason, the swards are usually …


Micro-Field Assessment Of Soil Erosion And Surface Runoff Using Mini Rainfall Simulator In Upper River Njoro Watershed In Kenya, J. O. Onyando, M. O. Okelo, C. M. Gichaba, W. A. Shivoga, S. N. Miller Aug 2023

Micro-Field Assessment Of Soil Erosion And Surface Runoff Using Mini Rainfall Simulator In Upper River Njoro Watershed In Kenya, J. O. Onyando, M. O. Okelo, C. M. Gichaba, W. A. Shivoga, S. N. Miller

IGC Proceedings (1993-2023)

Soil erosion and surface runoff are consequences of integration of several factors and processes within a catchment. The use of a rainfall simulator and run off plots provides a valuable research tool and are often used in soil erosion and surface runoff studies. Cheruiyot (1984) used this approach to study infiltration rates and sediment yield in Kiboko, Kenya. The present study used the same method but with a mini-rainfall simulator (Kamphorst, 1987) to study the effects of different land use treatments on soil loss and surface runoff.


Validation Of The Software “Recycling Of Nutrients” In Dairy-Farms Of Western Cuba, I. Rodríguez, Gustavo Crespo, M. F. Días, S. Fraga Aug 2023

Validation Of The Software “Recycling Of Nutrients” In Dairy-Farms Of Western Cuba, I. Rodríguez, Gustavo Crespo, M. F. Días, S. Fraga

IGC Proceedings (1993-2023)

To maintain a good productivity in the soil-plant-animal system it is necessary to achieve an equilibrium between input and output of nutrients and energy. Models and simulation software have been proposed for this purpose. For dairy farms, models have been utilised to show the behaviour of different aspects, such as: feed utilisation, energy flow, digestibility values and daily weight gains (Freer et al., 1970; Assis & France, 1983, Bruce et al., 1984). However, there are few models showing the interaction between soil-plant- animal components of these systems. The objective of the present study was to validate the software …


Modelling Urine Nitrogen Production And Leaching Losses For Pasture-Based Dairying Systems, I. M. Brookes, D. J. Horne Aug 2023

Modelling Urine Nitrogen Production And Leaching Losses For Pasture-Based Dairying Systems, I. M. Brookes, D. J. Horne

IGC Proceedings (1993-2023)

Urine from dairy cattle grazing pastures with high crude protein (CP) concentrations is a major source of N lost in drainage water from New Zealand farms. This paper provides predictions of urinary N leaching losses for a range of stocking rates and levels of supplementation.


Management Options To Reduce N-Losses From Ploughed Grass-Clover, J. De Wit, G. J. Van Der Burgt, N. Van Eekeren Aug 2023

Management Options To Reduce N-Losses From Ploughed Grass-Clover, J. De Wit, G. J. Van Der Burgt, N. Van Eekeren

IGC Proceedings (1993-2023)

Nitrate (NO3-) leaching from grassland can be kept at acceptable levels, but is often high after ploughing for grassland renewal or for silage maize/grain production. In on-farm research with several organic farmers, management options are being explored to save scarce organic manure and to reduce N-losses.


Nutrient Cycling In A Tropical Grazing Land Ecosystem Of Southern India, K. S. T. K. Karunaichamy, Kailash Paliwal Aug 2023

Nutrient Cycling In A Tropical Grazing Land Ecosystem Of Southern India, K. S. T. K. Karunaichamy, Kailash Paliwal

IGC Proceedings (1993-2023)

The nutrient component of any ecosystem operates in a dynamic state through a series of inputs and outputs of the essential elements. Nutrients from plants are continuously transferred to soil via litter formation, which act as a reservoir for the plants in an ecosystem. Most of the studies on nutrient budgets and flux rates have been reported in forest communities and to a lesser degree in grassland. The present study was, therefore, aims to understand the variation of calcium (Ca) and magnesium (Mg) in the vegetation compartments and to quantify annual budget by estimating the annual uptake from soil and …


Integrated Nutrient Management For Natural Grasslands Of Mid-Hills Of Himalayas, I. Dev, S. Narayana, R. Singh, B. Misri, S. Sareen, S. Radotra Aug 2023

Integrated Nutrient Management For Natural Grasslands Of Mid-Hills Of Himalayas, I. Dev, S. Narayana, R. Singh, B. Misri, S. Sareen, S. Radotra

IGC Proceedings (1993-2023)

Livestock rearing is an important pursuit in mountain farming in India and plays a crucial role throughout the country. The preponderance of marginal and small landholdings (about 82%) in hilly regions does not allow the farmers to allocate even a small part of their land exclusively for forage production. In Himachal Pradesh state of India about 1.16 m ha (20% of the total area) is under permanent pastures and other grazing lands and none of the natural grasslands are fertilised in any form. Existing grasslands have deteriorated to such an extent that their carrying capacity is only 1.05 ACU (Adult …


Abiotic Resource Efficiency Of Grassland Production Systems In North-West Europe, M. Wachendorf, F. Taube Aug 2023

Abiotic Resource Efficiency Of Grassland Production Systems In North-West Europe, M. Wachendorf, F. Taube

IGC Proceedings (1993-2023)

Nitrate leaching and energy efficiency are key criteria of a resource efficient grassland production system. A four-year field experiment was conducted to evaluate the effects of N input and defoliation system on both criteria. The objective of this experiment was to develop strategies which help to facilitate future grassland production with maximum environmental friendliness.


Cap Reform And Nitrate Restrictions: Implications For Irish Grass Based Dairy Production Systems, Anne Marie Butler, M. Wallace, P. Dillon Aug 2023

Cap Reform And Nitrate Restrictions: Implications For Irish Grass Based Dairy Production Systems, Anne Marie Butler, M. Wallace, P. Dillon

IGC Proceedings (1993-2023)

The benefit of a systems approach to analysing production situations has long been recognised in agricultural research. The development and application of production-oriented dairy models offer tremendous capabilities for both encompassing the realities faced by producers while also considering the adaptation possibilities available to them in light of internal and external forces of change. This farm level dairy model represents one such approach. The objectives of the study were: (1) to develop a comprehensive farm-level model of Irish milk production systems and (2) to apply the model to identify optimal adaptation strategies of dairy farmers within the context of European …


Species-Rich Grassland As An Ecological Good In An Outcome-Based Payment Scheme, E. Bertke, R. Marggraf, Johannes Isselstein Aug 2023

Species-Rich Grassland As An Ecological Good In An Outcome-Based Payment Scheme, E. Bertke, R. Marggraf, Johannes Isselstein

IGC Proceedings (1993-2023)

Agriculture plays an important role in protecting the biodiversity of the rural environment. Since the reform of the EU's common agricultural policy (CAP) in 1992, agri-environment schemes have been supported by the EU within the framework of the second pillar of CAP. In these programmes, farmers were rewarded for environmental services. The predominantly action-oriented programmes imply particular disadvantages; they tend to lack economic efficiency and to fail with regard to the conservation and improvement of biodiversity (Kleijn & Sutherland, 2003; Wilhelm, 1999). This situation was the starting point for the development of an outcome-based payment scheme. We focus on the …


Silvopastoral Systems: Analyses Of An Alternative To Open Swards, James H. Mcadam, M. R. Mosquera-Losada, V. Papanastasis, Andrea Pardini, M. L. Rigueiro-Rodríguez Aug 2023

Silvopastoral Systems: Analyses Of An Alternative To Open Swards, James H. Mcadam, M. R. Mosquera-Losada, V. Papanastasis, Andrea Pardini, M. L. Rigueiro-Rodríguez

IGC Proceedings (1993-2023)

Silvopasture is a sustainable land use management practiced in most continents in the world including parts of southern Europe, but is not broadly used in northern and western Europe. The importance of this practice has been recognised and the last draft of the EU regulation by the European Agricultural Fund for Rural Development (http://europa.eu.int/comm/agriculture/capreform/rurdevprop_en.pdf) includes specifically funding for establishment of agroforestry practices in Europe. This paper discusses the advantages of managing semi intensive grassland within a silvopastoral system from an ecological, productive and social point of view in the south, south-central and western countries of Europe.


Sustainable Grazing On Saline Land In Western Australia - Multidisciplinary Research Linking Producers And Scientists, Hayley C. Norman, D. G. Masters, M. G. Wilmot, A. J. Rintoul, R. Silberstein, E. Lefroy, T. York Aug 2023

Sustainable Grazing On Saline Land In Western Australia - Multidisciplinary Research Linking Producers And Scientists, Hayley C. Norman, D. G. Masters, M. G. Wilmot, A. J. Rintoul, R. Silberstein, E. Lefroy, T. York

IGC Proceedings (1993-2023)

Dryland salinity is one of the most critical environmental issues challenging Western Australian farmers. Currently 10% of the cropping zone (1.8 million ha) is salt-affected and this is predicted to increase dramatically in the next 50 years (NLWRA, 2001). Animals grazing saline pasture systems represent the most likely large-scale opportunity for economic return from saline land in the short to medium term. To date, few farmers have invested in large-scale revegetation of saline land as the economic return from grazing has not been perceived to cover costs. Furthermore other benefits of saltland pasture systems, such as biodiversity, water use and …


Energy Use And Energy Use Efficiency Of Specialised Dairy Farms In Flanders, Marijke Meul, Frank Nevens, I. Verbruggen, D. Reheul Aug 2023

Energy Use And Energy Use Efficiency Of Specialised Dairy Farms In Flanders, Marijke Meul, Frank Nevens, I. Verbruggen, D. Reheul

IGC Proceedings (1993-2023)

Our highly mechanised agriculture largely depends on ever declining stocks of fossil energy and hence contributes to global warming through the emission of greenhouse gases. Therefore, energy use (efficiency) is an important aspect of eco-efficient and sustainable agricultural production systems. In this study, we estimated direct and indirect energy use on a representative set of specialised dairy farms in Flanders (334 farm datasets in 1989-1990 and 147 farm datasets in 2000-2001) and we calculated their energy use efficiency. We studied the observed evolution between 1989-1990 and 2000-2001.


Agroecosystem Performances Of Livestock Farms In A Mountain Area Of Sicily, L. Stringi, G. Alfieri, G. Amato, A. S. Frenda, D. Giambalvo, P. Iudicello Aug 2023

Agroecosystem Performances Of Livestock Farms In A Mountain Area Of Sicily, L. Stringi, G. Alfieri, G. Amato, A. S. Frenda, D. Giambalvo, P. Iudicello

IGC Proceedings (1993-2023)

Agroecosystem performance indicators (APIs) represent instruments for studying agroecosystem performance via an input/output approach and a knowledge base, with the aim of improving the sustainability level of the farm's activity (Tellarini & Caporali, 2000). This research used APIs to evaluate the influence of stocking rate on the performance (in terms of energy) of farms in a mountainous area of northern Sicily, Italy.


Low Input Techniques For Firebreak Covering: Agronomic Aspects, S. Caredda, Antonello Franca, F. Sanna, G. Seddaiu Aug 2023

Low Input Techniques For Firebreak Covering: Agronomic Aspects, S. Caredda, Antonello Franca, F. Sanna, G. Seddaiu

IGC Proceedings (1993-2023)

In Sardinia, wild fire prevention is traditionally "passive" , based on mechanical removal of vegetation and upper soil layers. This has a dramatic negative effect on plant diversity and soil erosion. This experiment concerns "active" prevention of wildfires, based on green covering and grazing of firebreaks. The objective was the establishment of a persistent green cover, to be grazed by animals to reduce fuel accumulation.


Cost Efficiency Of Agri-Environmental Schemes - Model Calculations In Central Europe For Grassland Extensification, H. Bergmann Aug 2023

Cost Efficiency Of Agri-Environmental Schemes - Model Calculations In Central Europe For Grassland Extensification, H. Bergmann

IGC Proceedings (1993-2023)

The use of grassland in less favoured areas is important for the protection of agro-biodiversity. However, under existing market conditions the use of low yielding grasslands is not efficient economically. For this reason the European Union is paying specific support to make extensive grasslands economically more attractive. The objective of this study was to analyse whether the existing agri-environmental scheme was the cheapest way to protect extensive grasslands.


Phytosociological And Economical Properties Of Some Water-Meadows Of Nemunas, Lithuania, L. Baležentienė, E. Venskutonienė Aug 2023

Phytosociological And Economical Properties Of Some Water-Meadows Of Nemunas, Lithuania, L. Baležentienė, E. Venskutonienė

IGC Proceedings (1993-2023)

The water meadows of Nemunas in Lithuania have a high biological diversity as well as economic value. This paper describes the syntaxonomic type of meadow communities, plant species diversity of some water meadows of Nemunas, estimating the productivity of these grasslands in the summers of 2002 and 2003 and the optimal method of management.


Role Of Grasslands And Grassland Management For Biogeochemical Cycles And Biodiversity. Setting Up Long-Term Manipulation Experiments In France, G. Lemaire, Jean-François Soussana, J. C. Emile, A. Chabbi, F. Louault, P. Loiseau, Bertrand Dumont, X. Charrier Aug 2023

Role Of Grasslands And Grassland Management For Biogeochemical Cycles And Biodiversity. Setting Up Long-Term Manipulation Experiments In France, G. Lemaire, Jean-François Soussana, J. C. Emile, A. Chabbi, F. Louault, P. Loiseau, Bertrand Dumont, X. Charrier

IGC Proceedings (1993-2023)

Land use for grassland is recognised to have some beneficial effects for biodiversity and the environment: (i) regulation of the water cycle and protection of soils against erosion, (ii) accumulation of organic matter in soil and sequestration of atmospheric C, (iii) regulation of the N cycle and attenuation of the risk for N leaching, (iv) recycling of nutrients and improvement of soil quality, (v) improvement of biodiversity of vegetation, soil microbes and micro- and meso-fauna. All these effects depend upon the management of the grassland: cutting vs. grazing, stocking density, level of N inputs. Management decisions often result from short- …