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Mestre Irène - One of the best experts on this subject based on the ideXlab platform.
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Approches environnementales et gestion des pâturages
Études rurales, 2021Co-Authors: Mestre IrèneAbstract:Cet article analyse les effets de la diversité des conceptions de l’environnement dans un processus de décentralisation de la gestion des pâturages en s’appuyant sur le cadre conceptuel de la décentralisation de la gestion des ressources naturelles développé par Arun Agrawal et Elinor Ostrom. Au Kirghizstan, la mise en place d’institutions de gestion communautaire des pâturages à l’échelle locale, les associations d’usagers des pâturages, a fait émerger l’opposition entre les conceptions de l’environnement portées par les acteurs gouvernementaux, non gouvernementaux et internationaux. À l’échelle locale, les associations d’usagers des pâturages s’approprient ces approches de manière sélective pour définir les relations avec les usagers non agropastoraux et s’organisent pour influencer les acteurs de l’échelle nationale.This article aims to analyse the effects of the diversity of the concepts of environment in the Pasture Management decentralisation process. In this respect, we use the conceptual framework developed by Agrawal and Ostrom. In Kyrgyzstan, the implementation of local community-based institutions for Pasture Management reinvigorated the discrepancies between the concepts of environment of the governmental, non-governmental and international stakeholders. At the local level, Pasture user associations appropriate these concepts selectively in order to define their interactions with non-agropastoral users and organize themselves to influence national-level stakeholders
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La contribution de la gestion communautaire des ressources pastorales à la résilience des communautés rurales post-soviétiques, le cas du Kirghizistan
HAL CCSD, 2019Co-Authors: Mestre IrèneAbstract:My research looked at pastoral resources and agropastoral systems after the implementation in 2009 of community-based Pasture Management over all the territory of Kyrgyzstan. I investigated how the community-based Pasture Management contributes to the resilience of rural communities. I used multiple embedded case-studies in order to comprehensively embrace the linkages between land-use, resource dynamics and governance. The case-studies were three rural municipalities and their Pastures, which form socio-ecological systems. National level was also examined. Data-collection was conducted through extensive field-work in the rural communities, participant observation in NGOs implementing projects in the domain of Pasture Management at national level, and literature review. I used qualitative data analysis through thematization and basic statistic analysis for quantitative data. The theoretical framework combines the approach of Common-pool resource Management by Ostrom (1990) and the resilience of spatial socio-ecological systems by Aschan-Leygonie (2000). Based on them I elaborated a qualitative framework to analyze the contribution of Community-Based Pasture Management (CBPM) on spatial resilience of socio-ecological systems. As Pasture, I understand the Pastures them-selves as well as all the other resources necessary for their use, e.g. water and access infrastructure.My results show that community-based Management fails to create feed-back loops between the environment, the practices and the Management measures. Pasture Committees do not carry out formal data collection on resource dynamics, neither on the impacts of use. Their actions merely follow Pasture user interests which are potentially led by indigenous knowledge on Pasture condition, although there is a need for more research on this point.However, in general, community-based Pasture Management positively affects the resilience of rural communities. First, by its open-nature, remote and marginalized households can take part in the decision-making. Second, the investment generated allows for repair and maintenance of infrastructure (roads, bridges) giving access to remote Pasture, thereby limiting livestock concentration on most accessible Pastures. Third, it creates interactions of a new type between agropastoral and non-agropastoral Pasture users, as well as between local stakeholders and national-level stakeholders. Thus, community-based Pasture Management is a factor of the expansion of local socio-ecological systems and of the diversification and intensification of their interactions, within the systems, as well as across scales.Dans le cadre de cette recherche, nous nous sommes penchées sur les dynamiques à l’œuvre dans les systèmes agropastoraux après la mise en place, depuis 2009, de la gestion communautaire des ressources pastorales sur tout le territoire du Kirghizstan. Nous nous sommes interrogées sur la contribution de la gestion communautaire des ressources pastorales à la résilience des communautés rurales. La méthodologie de la recherche utilisée est l’étude de cas multiple imbriquée, de manière à prendre en compte de manière ouverte les interactions entre l’utilisation des terres, les dynamiques des ressources et la gouvernance. Les cas d’étude sélectionnés sont trois communes rurales et leurs pâturages qui forment ainsi trois systèmes socio-écologiques. Le niveau national est également pris en compte. Les données ont été collectées par des enquêtes de terrain et l’observation participante dans les communes rurales et dans les ONG en charge de projets sur la gestion des ressources pastorales au niveau national. Une revue de la littérature a également été menée. Le traitement qualitatif des données s’est fait par thématisation et les données quantitatives ont fait l’objet d’analyses statistiques simples. Le cadre conceptuel articule les principes pour la gestion d’un bien commun d’Elinor Ostrom (1990) et l’approche pour l’étude de la résilience des systèmes spatiaux de Christina Aschan-Leygonie (2000). Une grille de la contribution de la gestion communautaire des ressources pastorales à la résilience spatiale des systèmes socio-écologiques a servi de guide pour l’analyse.Les résultats de cette recherche mettent en évidence l’échec de la gestion communautaire à créer des boucles de rétroaction entre l’environnement, les pratiques et les mesures de gestion. Les organes exécutifs de la gestion communautaire ne collectent pas formellement de données sur l’état des pâturages ni sur les effets des usages. Leurs actions suivent principalement les intérêts des usagers des pâturages. Des recherches complémentaires sont nécessaires pour évaluer si les usagers des pâturages mènent un suivi des pâturages grâce aux savoirs locaux et si celui-ci est pris en compte dans les pratiques.Cependant, de manière générale, la gestion communautaire des ressources pastorales a un effet positif sur la résilience des communautés rurales. Premièrement, par son ouverture, elle permet aux familles les plus éloignées, et marginalisées dans la prise de décision sur la gestion des ressources pastorales, de faire entendre leur voix. Deuxièmement, l’accès à des pâturages peu utilisés est rendu possible par les réparations d’infrastructures financées par les investissements liés à la réforme. Ainsi, la pression du bétail sur les pâturages est, au moins partiellement, diminuée. Troisièmement, la gestion communautaire des ressources pastorales crée des interactions d’un type nouveau entre les usagers des pâturages agropastoraux et non-agropastoraux, ainsi qu’entre les acteurs locaux et nationaux. Elle offre notamment un cadre pour des stratégies ascendantes de défense des intérêts locaux auprès des structures gouvernementales et non-gouvernementales de l’échelle nationale. Ainsi, la gestion communautaire des ressources pastorales est un facteur de l’expansion des systèmes socio-écologiques locaux, de diversification et d’intensification de leurs interactions à l’intérieur du système et avec les systèmes de niveaux supérieurs
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When Shepherds Mine Mountains: The Impact of Artisanal Mining on Agropastoral Systems in Kyrgyzstan. Case Study of Naryn Province
Journal of Alpine research Revue de géographie alpine, 2017Co-Authors: Mestre IrèneAbstract:In 2009, Kyrgyzstan adopted a community-based Pasture Management model. While agropastoralism is the main subsistence activity for 65% of the population living in rural areas, Pastures are also an essential resource for other activities, such as mining. By analysing a rural municipality where agropastoralism and mining co-exist, we explore the impacts of artisanal mining activities on community-based Pasture Management and territorial resilience. Our key findings show that mining income is capitalised in the form of livestock, and that the mechanisms for animal herding by agropastoralists who are not involved in mining activities and who live on the periphery and have little access to formal decision-making processes are at risk of further marginalisation. Furthermore, the lack of mechanisms for collecting and analysing data on the state of the natural resources necessary for agropastoralism, such as water and Pastures, poses a risk to community-based Pasture Management. Finally, interactions within the system and between the system and external components are a transversal issue for the maintenance of community-based Management. Thus, the co-existence of high income–generating activities and traditional activities such as agropastoralism does not limit community-based Management and can even be a lever for a dynamic process that helps to support the creation of Management rules.Le Kirghizistan a adopté en 2009 un mode de gestion communautaire des pâturages. Alors que l’agropastoralisme est l’activité de subsistance de 65 % de la population qui vit en zone rurale, les pâturages représentent également une ressource essentielle pour d’autres activités telles que les activités minières. À travers l’étude d’une municipalité rurale où mines et élevage coexistent, nous analysons les impacts des activités minières artisanales sur la gestion communautaire des pâturages et sur la résilience de ces territoires. Les principaux résultats mettent en avant une capitalisation des revenus miniers sous forme de bétail ce qui conduit à l’augmentation du confiage du bétail aux agropastoralistes non impliqués dans les activités minières vivant en périphéries du village. Ces agropastoralistes ont un accès limité aux processus formels de prise de décision, ce qui renforce le risque de marginalisation de ces acteurs. Par ailleurs, le manque de mécanisme de collecte et de traitement de données sur l’état des ressources naturelles nécessaires à l’agropastoralisme, eau et pâturages, s’avère être un risque pour la gestion communautaire. Enfin, les interactions internes et externes au système représentent un enjeu transversal pour la continuité de gestion communautaire. Ainsi, la coexistence d’une activité générant des hauts revenus avec une activité traditionnelle telle que l’agropastoralisme n’est pas un facteur limitatif d’une gestion communautaire des ressources naturelles et peut, à l’inverse, se révéler être un déclencheur pour dynamiser le processus d’élaboration de règles de gestion
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Quand les bergers creusent la montagne. Impact des activités minières artisanales sur les systèmes agropastoraux du Kirghizstan. Étude de cas dans la région de Naryn
Journal of Alpine research Revue de géographie alpine, 2017Co-Authors: Mestre IrèneAbstract:Le Kirghizistan a adopté en 2009 un mode de gestion communautaire des pâturages. Alors que l’agropastoralisme est l’activité de subsistance de 65 % de la population qui vit en zone rurale, les pâturages représentent également une ressource essentielle pour d’autres activités telles que les activités minières. À travers l’étude d’une municipalité rurale où mines et élevage coexistent, nous analysons les impacts des activités minières artisanales sur la gestion communautaire des pâturages et sur la résilience de ces territoires. Les principaux résultats mettent en avant une capitalisation des revenus miniers sous forme de bétail ce qui conduit à l’augmentation du confiage du bétail aux agropastoralistes non impliqués dans les activités minières vivant en périphéries du village. Ces agropastoralistes ont un accès limité aux processus formels de prise de décision, ce qui renforce le risque de marginalisation de ces acteurs. Par ailleurs, le manque de mécanisme de collecte et de traitement de données sur l’état des ressources naturelles nécessaires à l’agropastoralisme, eau et pâturages, s’avère être un risque pour la gestion communautaire. Enfin, les interactions internes et externes au système représentent un enjeu transversal pour la continuité de gestion communautaire. Ainsi, la coexistence d’une activité générant des hauts revenus avec une activité traditionnelle telle que l’agropastoralisme n’est pas un facteur limitatif d’une gestion communautaire des ressources naturelles et peut, à l’inverse, se révéler être un déclencheur pour dynamiser le processus d’élaboration de règles de gestion.In 2009, Kyrgyzstan adopted a community-based Pasture Management model. While agropastoralism is the main subsistence activity for 65% of the population living in rural areas, Pastures are also an essential resource for other activities, such as mining. By analysing a rural municipality where agropastoralism and mining co-exist, we explore the impacts of artisanal mining activities on community-based Pasture Management and territorial resilience. Our key findings show that mining income is capitalised in the form of livestock, and that the mechanisms for animal herding by agropastoralists who are not involved in mining activities and who live on the periphery and have little access to formal decision-making processes are at risk of further marginalisation. Furthermore, the lack of mechanisms for collecting and analysing data on the state of the natural resources necessary for agropastoralism, such as water and Pastures, poses a risk to community-based Pasture Management. Finally, interactions within the system and between the system and external components are a transversal issue for the maintenance of community-based Management. Thus, the co-existence of high income–generating activities and traditional activities such as agropastoralism does not limit community-based Management and can even be a lever for a dynamic process that helps to support the creation of Management rules
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When Shepherds Mine Mountains: The Impact of Artisanal Mining on Agropastoral Systems in Kyrgyzstan. Case Study of Naryn Province
Association pour la diffusion de la recherche alpine, 2017Co-Authors: Mestre IrèneAbstract:International audienceIn 2009, Kyrgyzstan adopted a community-based Pasture Management model. While agropastoralism is the main subsistence activity for 65% of the population living in rural areas, Pastures are also an essential resource for other activities, such as mining. By analysing a rural municipality where agropastoralism and mining co-exist, we explore the impacts of artisanal mining activities on community-based Pasture Management and territorial resilience. Our key findings show that mining income is capitalised in the form of livestock, and that the mechanisms for animal herding by agropastoralists who are not involved in mining activities and who live on the periphery and have little access to formal decision-making processes are at risk of further marginalisation. Furthermore, the lack of mechanisms for collecting and analysing data on the state of the natural resources necessary for agropastoralism, such as water and Pastures, poses a risk to community-based Pasture Management. Finally, interactions within the system and between the system and external components are a transversal issue for the maintenance of community-based Management. Thus, the co-existence of high income–generating activities and traditional activities such as agropastoralism does not limit community-based Management and can even be a lever for a dynamic process that helps to support the creation of Management rules
Irène Mestre - One of the best experts on this subject based on the ideXlab platform.
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When Shepherds Mine Mountains: The Impact of Artisanal Mining on Agropastoral Systems in Kyrgyzstan. Case Study of Naryn Province
Revue De Geographie Alpine-journal of Alpine Research, 2017Co-Authors: Irène MestreAbstract:In 2009, Kyrgyzstan adopted a community-based Pasture Management model. While agropastoralism is the main subsistence activity for 65% of the population living in rural areas, Pastures are also an essential resource for other activities, such as mining. By analysing a rural municipality where agropastoralism and mining co-exist, we explore the impacts of artisanal mining activities on community-based Pasture Management and territorial resilience. Our key findings show that mining income is capitalised in the form of livestock, and that the mechanisms for animal herding by agropastoralists who are not involved in mining activities and who live on the periphery and have little access to formal decision-making processes are at risk of further marginalisation. Furthermore, the lack of mechanisms for collecting and analysing data on the state of the natural resources necessary for agropastoralism, such as water and Pastures, poses a risk to community-based Pasture Management. Finally, interactions within the system and between the system and external components are a transversal issue for the maintenance of community-based Management. Thus, the co-existence of high income–generating activities and traditional activities such as agropastoralism does not limit community-based Management and can even be a lever for a dynamic process that helps to support the creation of Management rules.
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Quand les bergers creusent la montagne. Impact des activités minières artisanales sur les systèmes agropastoraux du Kirghizstan. Étude de cas dans la région de Naryn
Institut de Géographie Alpine, 2017Co-Authors: Irène MestreAbstract:In 2009, Kyrgyzstan adopted a community-based Pasture Management model. While agropastoralism is the main subsistence activity for 65% of the population living in rural areas, Pastures are also an essential resource for other activities, such as mining. By analysing a rural municipality where agropastoralism and mining co-exist, we explore the impacts of artisanal mining activities on community-based Pasture Management and territorial resilience. Our key findings show that mining income is capitalised in the form of livestock, and that the mechanisms for animal herding by agropastoralists who are not involved in mining activities and who live on the periphery and have little access to formal decision-making processes are at risk of further marginalisation. Furthermore, the lack of mechanisms for collecting and analysing data on the state of the natural resources necessary for agropastoralism, such as water and Pastures, poses a risk to community-based Pasture Management. Finally, interactions within the system and between the system and external components are a transversal issue for the maintenance of community-based Management. Thus, the co-existence of high income–generating activities and traditional activities such as agropastoralism does not limit community-based Management and can even be a lever for a dynamic process that helps to support the creation of Management rules
John A Stuedemann - One of the best experts on this subject based on the ideXlab platform.
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surface soil changes during twelve years of Pasture Management in the southern piedmont usa
Soil Science Society of America Journal, 2010Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Surface soil characteristics are of key importance in assessing the sustainability of agricultural Management systems. We evaluated the factorial combination of nutrient source (inorganic, mixed organic + inorganic, and organic as broiler litter) and forage utilization (unharvested, low and high cattle grazing pressure, and hayed) on soil organic matter during 12 yr of Pasture Management on a Typic Kanhapludult in Georgia. Nutrient source had very little effect on bulk density, soil organic C (SOC), and total soil N (TSN). Forage utilization greatly affected all soil properties, more so nearest the surface. For example, SOC at a depth of 0 to 3 cm under low grazing pressure was 47.6 g kg -1 and under haying was 28.8 g kg -1 (P < 0.001), while at 3 to 6 cm it was 20.1 and 14.9 g kg -1 , respectively (P = 0.04), and at 6 to 12 cm it was 12.7 and 11.0 g kg -1 , respectively (P = 0.59). Soil bulk density was inversely related to SOC. Total SOC (0-20 cm) plus surface residue C was 3.6 ± 3.6 Mg C ha -1 greater (mean ± standard deviation among six nutrient source x forage utilization comparisons) in the zone nearest shade and water sources than farther away. Sequestration of TSN in the surface 6 cm averaged 8 ± 8 kg N ha -1 yr -1 (mean ± standard deviation among three nutrient source comparisons) when hayed, 31 ± 15 kg N ha -1 yr -1 when left unharvested, and 74 ± 5 kg N ha -1 yr -1 when grazed by cattle with either low or high grazing pressure. These results indicate the large potential of well-managed grazing systems to improve the quality and functioning of soils in the southeastern United States.
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soil profile organic carbon and total nitrogen during 12 years of Pasture Management in the southern piedmont usa
Agriculture Ecosystems & Environment, 2009Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Abstract Soil organic C (SOC) and total soil N (TSN) sequestration estimates are needed to improve our understanding of Management influences on soil fertility and terrestrial C cycling related to greenhouse gas emission. We evaluated the factorial combination of nutrient source (inorganic, mixed inorganic and organic, and organic as broiler litter) and forage utilization (unharvested, low and high cattle grazing pressure, and hayed monthly) on soil-profile distribution (0–150 cm) of SOC and TSN during 12 years of Pasture Management on a Typic Kanhapludult (Acrisol) in Georgia, USA. Nutrient source rarely affected SOC and TSN in the soil profile, despite addition of 73.6 Mg ha−1 (dry weight) of broiler litter during 12 years of treatment. At the end of 12 years, contents of SOC and TSN at a depth of 0–90 cm under haying were only 82 ± 5% (mean ± S.D. among treatments) of those under grazed Management. Within grazed Pastures, contents of SOC and TSN at a depth of 0–90 cm were greatest within 5 m of shade and water sources and only 83 ± 7% of maximum at a distance of 30 m and 92 ± 14% of maximum at a distance of 80 m, suggesting a zone of enrichment within Pastures due to animal behavior. During 12 years, the annual rate of change in SOC (0–90 cm) followed the order: low grazing pressure (1.17 Mg C ha−1 year−1) > unharvested (0.64 Mg C ha−1 year−1) = high grazing pressure (0.51 Mg C ha−1 year−1) > hayed (−0.22 Mg C ha−1 year−1). This study demonstrated that surface accumulation of SOC and TSN occurred, but that increased variability and loss of SOC with depth reduced the significance of surface effects.
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particulate and non particulate fractions of soil organic carbon under Pastures in the southern piedmont usa
Environmental Pollution, 2002Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Pasture Management can be effective at sequestering soil organic C. We determined the depth distribution of particulate organic C (POC), non-particulate organic C (NPOC), particulate-to-total organic C (POC-to-TOC) ratio, and particulate organic C-to-N (POC-to-N) ratio under Pastures near Watkinsville, GA, USA. POC was highly related with total organic C (TOC), but became an increasingly larger portion of TOC near the soil surface, where both pools were greatest. POC and NPOC were (i) greater under Pasture than under conservation-tillage cropland, (ii) greater when Pasture was grazed than when hayed, (iii) marginally greater with higher fertilization of Pasture, (iv) greater with higher frequency of endophyte infection of tall fescue, and (v) greater under increasing stand age of grass. Soil under Pasture comparisons that had greater TOC content had (i) larger improvements in POC than in NPOC and (ii) lower POC-to-N ratios, suggesting improvement in biochemical soil quality, as well as soil C sequestration. Published by Elsevier Science Ltd.
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particulate and non particulate fractions of soil organic carbon under Pastures in the southern piedmont usa
Environmental Pollution, 2002Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Pasture Management can be effective at sequestering soil organic C. We determined the depth distribution of particulate organic C (POC), non-particulate organic C (NPOC), particulate-to-total organic C (POC-to-TOC) ratio, and particulate organic C-to-N (POC-to-N) ratio under Pastures near Watkinsville, GA, USA. POC was highly related with total organic C (TOC), but became an increasingly larger portion of TOC near the soil surface, where both pools were greatest. POC and NPOC were (i) greater under Pasture than under conservation-tillage cropland, (ii) greater when Pasture was grazed than when hayed, (iii) marginally greater with higher fertilization of Pasture, (iv) greater with higher frequency of endophyte infection of tall fescue, and (v) greater under increasing stand age of grass. Soil under Pasture comparisons that had greater TOC content had (i) larger improvements in POC than in NPOC and (ii) lower POC-to-N ratios, suggesting improvement in biochemical soil quality, as well as soil C sequestration.
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soil organic c and n pools under long term Pasture Management in the southern piedmont usa
Soil Biology & Biochemistry, 2000Co-Authors: Alan J Franzluebbers, John A Stuedemann, Harry H Schomberg, S R WilkinsonAbstract:Soil organic matter pools under contrasting long-term Management systems provide insight into potentials for sequestering soil C, sustaining soil fertility and functioning of the soil‐atmospheric interface. We compared soil C and N pools (total, particulate and microbial) under Pastures (1) varying due to harvest technique (grazing or haying), species composition (cool- or warm-season), stand age and previous land use and (2) in comparison with other land uses. Grazed tall fescue-common bermudagrass Pasture (20 yr old) had greater soil organic C (31%), total N (34%), particulate organic C (66%), particulate organic N (2.4 fold) and soil microbial biomass C (28%) at a depth of 0‐200 mm than adjacent land in conservation-tillage cropland (24 yr old). Soil organic C and total N at a depth of 0‐200 mm averaged 3800 and 294 g m ˇ2 , respectively, under grazed bermudagrass and 3112 and 219 g m ˇ2 , respectively, under hayed bermudagrass. A chronosequence of grazed tall fescue suggested soil organic N sequestration rates of 7.3, 4.4 and 0.6 g m ˇ2 yr ˇ1 to a depth of 200 mm during 0‐10, 10‐30 and 30‐50 yr, respectively. Soil C storage under long-term grazed tall fescue was 85 to 88% of that under forest, whereas soil N storage was 77 to 90% greater under grazed tall fescue than under forest. Properly grazed Pastures in the Southern Piedmont USA have great potential to restore natural soil fertility, sequester soil organic C and N and increase soil biological activity. Published by Elsevier Science Ltd.
Alan J Franzluebbers - One of the best experts on this subject based on the ideXlab platform.
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surface soil changes during twelve years of Pasture Management in the southern piedmont usa
Soil Science Society of America Journal, 2010Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Surface soil characteristics are of key importance in assessing the sustainability of agricultural Management systems. We evaluated the factorial combination of nutrient source (inorganic, mixed organic + inorganic, and organic as broiler litter) and forage utilization (unharvested, low and high cattle grazing pressure, and hayed) on soil organic matter during 12 yr of Pasture Management on a Typic Kanhapludult in Georgia. Nutrient source had very little effect on bulk density, soil organic C (SOC), and total soil N (TSN). Forage utilization greatly affected all soil properties, more so nearest the surface. For example, SOC at a depth of 0 to 3 cm under low grazing pressure was 47.6 g kg -1 and under haying was 28.8 g kg -1 (P < 0.001), while at 3 to 6 cm it was 20.1 and 14.9 g kg -1 , respectively (P = 0.04), and at 6 to 12 cm it was 12.7 and 11.0 g kg -1 , respectively (P = 0.59). Soil bulk density was inversely related to SOC. Total SOC (0-20 cm) plus surface residue C was 3.6 ± 3.6 Mg C ha -1 greater (mean ± standard deviation among six nutrient source x forage utilization comparisons) in the zone nearest shade and water sources than farther away. Sequestration of TSN in the surface 6 cm averaged 8 ± 8 kg N ha -1 yr -1 (mean ± standard deviation among three nutrient source comparisons) when hayed, 31 ± 15 kg N ha -1 yr -1 when left unharvested, and 74 ± 5 kg N ha -1 yr -1 when grazed by cattle with either low or high grazing pressure. These results indicate the large potential of well-managed grazing systems to improve the quality and functioning of soils in the southeastern United States.
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soil profile organic carbon and total nitrogen during 12 years of Pasture Management in the southern piedmont usa
Agriculture Ecosystems & Environment, 2009Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Abstract Soil organic C (SOC) and total soil N (TSN) sequestration estimates are needed to improve our understanding of Management influences on soil fertility and terrestrial C cycling related to greenhouse gas emission. We evaluated the factorial combination of nutrient source (inorganic, mixed inorganic and organic, and organic as broiler litter) and forage utilization (unharvested, low and high cattle grazing pressure, and hayed monthly) on soil-profile distribution (0–150 cm) of SOC and TSN during 12 years of Pasture Management on a Typic Kanhapludult (Acrisol) in Georgia, USA. Nutrient source rarely affected SOC and TSN in the soil profile, despite addition of 73.6 Mg ha−1 (dry weight) of broiler litter during 12 years of treatment. At the end of 12 years, contents of SOC and TSN at a depth of 0–90 cm under haying were only 82 ± 5% (mean ± S.D. among treatments) of those under grazed Management. Within grazed Pastures, contents of SOC and TSN at a depth of 0–90 cm were greatest within 5 m of shade and water sources and only 83 ± 7% of maximum at a distance of 30 m and 92 ± 14% of maximum at a distance of 80 m, suggesting a zone of enrichment within Pastures due to animal behavior. During 12 years, the annual rate of change in SOC (0–90 cm) followed the order: low grazing pressure (1.17 Mg C ha−1 year−1) > unharvested (0.64 Mg C ha−1 year−1) = high grazing pressure (0.51 Mg C ha−1 year−1) > hayed (−0.22 Mg C ha−1 year−1). This study demonstrated that surface accumulation of SOC and TSN occurred, but that increased variability and loss of SOC with depth reduced the significance of surface effects.
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particulate and non particulate fractions of soil organic carbon under Pastures in the southern piedmont usa
Environmental Pollution, 2002Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Pasture Management can be effective at sequestering soil organic C. We determined the depth distribution of particulate organic C (POC), non-particulate organic C (NPOC), particulate-to-total organic C (POC-to-TOC) ratio, and particulate organic C-to-N (POC-to-N) ratio under Pastures near Watkinsville, GA, USA. POC was highly related with total organic C (TOC), but became an increasingly larger portion of TOC near the soil surface, where both pools were greatest. POC and NPOC were (i) greater under Pasture than under conservation-tillage cropland, (ii) greater when Pasture was grazed than when hayed, (iii) marginally greater with higher fertilization of Pasture, (iv) greater with higher frequency of endophyte infection of tall fescue, and (v) greater under increasing stand age of grass. Soil under Pasture comparisons that had greater TOC content had (i) larger improvements in POC than in NPOC and (ii) lower POC-to-N ratios, suggesting improvement in biochemical soil quality, as well as soil C sequestration. Published by Elsevier Science Ltd.
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particulate and non particulate fractions of soil organic carbon under Pastures in the southern piedmont usa
Environmental Pollution, 2002Co-Authors: Alan J Franzluebbers, John A StuedemannAbstract:Pasture Management can be effective at sequestering soil organic C. We determined the depth distribution of particulate organic C (POC), non-particulate organic C (NPOC), particulate-to-total organic C (POC-to-TOC) ratio, and particulate organic C-to-N (POC-to-N) ratio under Pastures near Watkinsville, GA, USA. POC was highly related with total organic C (TOC), but became an increasingly larger portion of TOC near the soil surface, where both pools were greatest. POC and NPOC were (i) greater under Pasture than under conservation-tillage cropland, (ii) greater when Pasture was grazed than when hayed, (iii) marginally greater with higher fertilization of Pasture, (iv) greater with higher frequency of endophyte infection of tall fescue, and (v) greater under increasing stand age of grass. Soil under Pasture comparisons that had greater TOC content had (i) larger improvements in POC than in NPOC and (ii) lower POC-to-N ratios, suggesting improvement in biochemical soil quality, as well as soil C sequestration.
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soil organic c and n pools under long term Pasture Management in the southern piedmont usa
Soil Biology & Biochemistry, 2000Co-Authors: Alan J Franzluebbers, John A Stuedemann, Harry H Schomberg, S R WilkinsonAbstract:Soil organic matter pools under contrasting long-term Management systems provide insight into potentials for sequestering soil C, sustaining soil fertility and functioning of the soil‐atmospheric interface. We compared soil C and N pools (total, particulate and microbial) under Pastures (1) varying due to harvest technique (grazing or haying), species composition (cool- or warm-season), stand age and previous land use and (2) in comparison with other land uses. Grazed tall fescue-common bermudagrass Pasture (20 yr old) had greater soil organic C (31%), total N (34%), particulate organic C (66%), particulate organic N (2.4 fold) and soil microbial biomass C (28%) at a depth of 0‐200 mm than adjacent land in conservation-tillage cropland (24 yr old). Soil organic C and total N at a depth of 0‐200 mm averaged 3800 and 294 g m ˇ2 , respectively, under grazed bermudagrass and 3112 and 219 g m ˇ2 , respectively, under hayed bermudagrass. A chronosequence of grazed tall fescue suggested soil organic N sequestration rates of 7.3, 4.4 and 0.6 g m ˇ2 yr ˇ1 to a depth of 200 mm during 0‐10, 10‐30 and 30‐50 yr, respectively. Soil C storage under long-term grazed tall fescue was 85 to 88% of that under forest, whereas soil N storage was 77 to 90% greater under grazed tall fescue than under forest. Properly grazed Pastures in the Southern Piedmont USA have great potential to restore natural soil fertility, sequester soil organic C and N and increase soil biological activity. Published by Elsevier Science Ltd.
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subhumid Pasture soil microbial communities affected by presence of grazing but not grazing Management
Applied Soil Ecology, 2012Co-Authors: Lawrence G Oates, Teri C Balser, Randall D JacksonAbstract:Management-intensive rotational grazing has been shown to stimulate net primary production in subhumid Pastures compared to extensive grazing strategies. The degree to which this represents a direct effect on plant developmental stage and community composition, and/or indirect effects of grazing on microbial community structure and nutrient feedback to production is an open question. To better understand whether the effects of Pasture Management on microbial communities led to indirect nutrient feedbacks, we analyzed microbial lipids and environmental and physical factors of surface soils under four Pasture Management treatments – Management-intensive rotational grazing, continuous grazing, harvesting for hay, and an unmanaged control. Principal component analysis indicated microbial community structure under our two grazed treatments was different than that of ungrazed treatments. While there was no effect of treatments on total microbial biomass, guild comparisons revealed lower fungal-to-bacterial ratios, lower arbuscular mycorrhizal fungi concentrations, and higher actinomycete biomarkers in soils under grazing, irrespective of grazing Management treatments. Gram-positive and anaerobic bacteria biomarker abundance was greater in treatments that included grazing and no Management when compared to the treatment where biomass was harvested mechanically. There was no evidence of treatment effects on either Gram-negative bacteria or saprotrophic fungi. Regression tree analysis identified litter quality as the main correlate of differences in the microbial community between grazed and ungrazed treatments. Lower root C:N predicted lower F:B and biomarkers of the bacterial guilds Gm+ and actinomycetes, which were dominant in the grazing treatments, while higher root C:N predicted higher F:B and the guild biomarkers of AMF, which dominated in the ungrazed treatments. These results indicate that greater forage production observed in humid and subhumid regions under Management-intensive rotational grazing likely stems from the direct effects on plant developmental stage and plant community composition rather than microbial mediated nutrient feedbacks from altered quantity and quality of plant litter. If the potential for a more favorable C balance in subhumid Pastures is realized, greater biomass production and therefore greater litter inputs as a result of the direct effects of Management-intensive rotational grazing on plant communities is the most likely mechanism.
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assessing ecosystem variance at different scales to generalize about Pasture Management in southern wisconsin
Agriculture Ecosystems & Environment, 2007Co-Authors: Randall D Jackson, Michael M Bell, Claudio GrattonAbstract:Pasture-based agroecosystems are an expanding enterprise in the northcentral U.S., but their structure and function have received little attention. We implemented a manipulative experiment to test Pasture Management effects on several agroecosystem variables at a university research farm in southcentral Wisconsin. In concert, we established a mensurative experiment across eight grass-based farms in the same region where we measured the same variables under existing land uses. Here we describe how total and relative variation in greenhouse gas fluxes, ground cover, soil arthropods, and soil inorganic N were distributed across nested spatial scales, Management treatments, and unexplained realms of these systems. This approach seeks to improve our understanding of Pasture Management effects on agroecosystem stocks andfluxes, while expandingour inferential space to awidergeographical area. Greenhousegasfluxes(CH4and N2O) were an order-ofmagnitude more variable than soil N pools, ground cover, or arthropod abundances. Most of the variance in these fluxes was at the subsample level, indicating the need for either more sampling chambers per Management treatment or an efficient stratification scheme or both. Methane was more variable farm-to-farm than among Management treatments within farms, while N2O showed the opposite pattern indicating that farmers arelikelytohavemoreinfluenceonN2OfluxesviaManagement thantheycanhave onCH4fluxes.Variabilityinarthropod groupsand ground cover was rather uniformly distributed across nested spatial scales, with the exception of beetles and harvestmen, which displayed little subsample variability. Soil inorganic N pools were more variable from farm-to-farm than among Management treatments, but most variation was at the subsample level. The least variable response was from the greenhouse gas CO2, which is driven by both auto- and heterotrophic organisms. Calculation of total and relativized coefficients of variation allowed for a standardized comparison of agroecosystem variables possessing disparate units of measure and facilitated conclusions about the generality of results across a broader geographical area than just a single farm. # 2007 Elsevier B.V. All rights reserved.