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Technical efficiency as a determinant of conversion to organic farming Texto completo
2015
Latruffe, Laure | Nauges, Celine | Desjeux, Yann
Technical efficiency of farms under conventional agriculture determines whether farmsconvert to organic or remain in conventional farming. Efficient farms may be more capable ofadopting new technologies and therefore convert to organic farming. By contrast, choosing toproduce for the organic niche market may be a survival strategy for technically inefficientconventional farms.A study on French crop farms investigates technical efficiency during the years precedingconversion in order to predict the probability of conversion. The results show an influence oftechnical efficiency of (conventional) farms on the probability to convert to organic farming,but that the direction depends on farm-size and production-type.Another study on dairy farms from North West France considers the effect of (past)technological change on the decision to convert. Results show that dairy farms switching toorganic farming show a higher efficiency in conventional farming, but experienced aslowdown in efficiency the year before conversion.
Mostrar más [+] Menos [-]Changes in soil organic carbon and aggregate stability after conversion to conservation tillage for seven years in the Huang-Huai-Hai Plain of China Texto completo
2015
SHU Xin, ZHU An-ning, ZHANG Jia-bao, YANG Wen-liang, XIN Xiu-li, ZHANG Xian-feng (Guest Editor Professor of Agricultural Economics in Developing and Transition Countries)
Changes in soil organic carbon and aggregate stability after conversion to conservation tillage for seven years in the Huang-Huai-Hai Plain of China Texto completo
2015
SHU Xin, ZHU An-ning, ZHANG Jia-bao, YANG Wen-liang, XIN Xiu-li, ZHANG Xian-feng (Guest Editor Professor of Agricultural Economics in Developing and Transition Countries)
Soil aggregate stability and organic carbon (OC) are regarded as effective indicators of soil structure and quality. A longterm field experiment was established in 2006 to examine the influence of tillage systems on soil aggregation and OC in a sandy loam soil in the Huang-Huai-Hai Plain of China. The study involved eight treatments: plowing every year with (TS) and without residue (T), plowing every 2 years with (2TS) and without residue (2T), plowing every 4 years with (4TS) and without residue (4T), and no plowing with (NTS) and without residue (NT). In 2013, soil samples were collected at depths of 0–5, 5–10 and 10–20 cm, and separated into three aggregate-size classes: macroaggregates (>250 μm), microaggregates (53–250 μm) and the silt+clay fraction (<53 μm) using wet sieving method. Soil parameters measured were water-stable aggregates, geometric mean diameter (GMD), mean weight diameter (MWD) and OC concentrations in different aggregate- size fractions and in bulk soil. The tillage treatments significantly (P<0.05) influenced soil aggregate stability and OC distribution. Higher MWD and GMD were observed in 2TS, 4TS and NTS as compared to T. With increasing soil depth, the amount of macroaggregates and MWD and GMD values were increased, while the proportions of microaggregates and the silt+clay fraction were declined. The OC concentrations in different aggregate fractions at all soil depths followed the order of macroaggregates>microaggregates>silt+clay fraction. In the 0–5 cm soil layer, concentrations of macroaggregateassociated OC in 2TS, 4TS and NTS were 14, 56 and 83% higher than for T, whereas T had the greatest concentration of OC associated with the silt+clay fraction in the 10–20 cm layer. Soil OC concentrations under 4TS and NTS were significantly higher (P<0.05) than that of T in the 0–10 cm layer. Residue retention promoted formation of macroaggregates, increased macroaggregate-associated OC concentrations and thus increased total soil OC stock. The macroaggregate-associated OC was positively correlated (R2=0.96) with soil OC concentration, while the silt+clay fraction-associated OC was negatively correlated (R2=0.82) with soil OC concentration. The concentration of soil OC was positively correlated with MWD (R2=0.94) and GMD (R2=0.92). We concluded that increasing tillage intensity led to a loss of carbon (C)-rich macroaggregates and an increase of C-depleted silt+clay fraction. The conservation tillage system, especially NTS and 4TS, increased soil aggregate stability and promoted OC accumulation in macroaggregates, provided the potential to improve soil C sequestration and soil structure in the Huang-Huai-Hai Plain of China.
Mostrar más [+] Menos [-]Changes in soil organic carbon and aggregate stability after conversion to conservation tillage for seven years in the Huang-Huai-Hai Plain of China Texto completo
2015
Xin SHU | An-ning ZHU | Jia-bao ZHANG | Wen-liang YANG | Xiu-li XIN | Xian-feng ZHANG
Soil aggregate stability and organic carbon (OC) are regarded as effective indicators of soil structure and quality. A long-term field experiment was established in 2006 to examine the influence of tillage systems on soil aggregation and OC in a sandy loam soil in the Huang-Huai-Hai Plain of China. The study involved eight treatments: plowing every year with (TS) and without residue (T), plowing every 2 years with (2TS) and without residue (2T), plowing every 4 years with (4TS) and without residue (4T), and no plowing with (NTS) and without residue (NT). In 2013, soil samples were collected at depths of 0–5, 5–10 and 10–20 cm, and separated into three aggregate-size classes: macroaggregates (>250 μm), microaggregates (53–250 μm) and the silt+clay fraction (<53 μm) using wet sieving method. Soil parameters measured were water-stable aggregates, geometric mean diameter (GMD), mean weight diameter (MWD) and OC concentrations in different aggregate-size fractions and in bulk soil. The tillage treatments significantly (P<0.05) influenced soil aggregate stability and OC distribution. Higher MWD and GMD were observed in 2TS, 4TS and NTS as compared to T. With increasing soil depth, the amount of macroaggregates and MWD and GMD values were increased, while the proportions of microaggregates and the silt+clay fraction were declined. The OC concentrations in different aggregate fractions at all soil depths followed the order of macroaggregates>microaggregates>silt+clay fraction. In the 0–5 cm soil layer, concentrations of macroaggregate-associated OC in 2TS, 4TS and NTS were 14, 56 and 83% higher than for T, whereas T had the greatest concentration of OC associated with the silt+clay fraction in the 10–20 cm layer. Soil OC concentrations under 4TS and NTS were significantly higher (P<0.05) than that of T in the 0–10 cm layer. Residue retention promoted formation of macroaggregates, increased macroaggregate-associated OC concentrations and thus increased total soil OC stock. The macroaggregate-associated OC was positively correlated (R2=0.96) with soil OC concentration, while the silt+clay fraction-associated OC was negatively correlated (R2=0.82) with soil OC concentration. The concentration of soil OC was positively correlated with MWD (R2=0.94) and GMD (R2=0.92). We concluded that increasing tillage intensity led to a loss of carbon (C)-rich macroaggregates and an increase of C-depleted silt+clay fraction. The conservation tillage system, especially NTS and 4TS, increased soil aggregate stability and promoted OC accumulation in macroaggregates, provided the potential to improve soil C sequestration and soil structure in the Huang-Huai-Hai Plain of China.
Mostrar más [+] Menos [-]An exhaustive inventory of coniferous trees in an agricultural landscape Texto completo
2015
Rousselet, Jérôme | Roques, Alain | Garcia, Jacques | Rossi, Jean-Pierre | Unité de recherche Zoologie Forestière (URZF) ; Institut National de la Recherche Agronomique (INRA) | Centre de Biologie pour la Gestion des Populations (UMR CBGP) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | ADRIEN (Région Centre Val de Loire), Sésame (métaprogramme SMaCH)
Various species of forest trees are commonly used for ornamental purposes and are therefore frequently found in non-forest ecosystems. These trees constitute a significant component of the trees outside forests (TOF). Although increasingly recognized as prominent feature of agricultural lands and built-up areas, not much is known, however, about TOF since they are generally absent from forest inventories.
Mostrar más [+] Menos [-]An exhaustive inventory of coniferous trees in an agricultural landscape Texto completo
2015
Rousselet, Jérôme | Roques, Alain | Garcia, Jacques | Rossi, Jean-Pierre
An exhaustive inventory of coniferous trees in an agricultural landscape Texto completo
2015
Rousselet, Jérôme | Roques, Alain | Garcia, Jacques | Rossi, Jean-Pierre
Various species of forest trees are commonly used for ornamental purposes and are therefore frequently found in non-forest ecosystems. These trees constitute a significant component of the trees outside forests (TOF). Although increasingly recognized as prominent feature of agricultural lands and built-up areas, not much is known, however, about TOF since they are generally absent from forest inventories.
Mostrar más [+] Menos [-]An exhaustive inventory of coniferous trees in an agricultural landscape Texto completo
2015
Rousselet, Jérôme | Roques, Alain | Garcia, Jacques | Rossi, Jean-Pierre
Various species of forest trees are commonly used for ornamental purposes and are therefore frequently found in non-forest ecosystems. These trees constitute a significant component of the trees outside forests (TOF). Although increasingly recognized as prominent feature of agricultural lands and built-up areas, not much is known, however, about TOF since they are generally absent from forest inventories. In the present study, we focus on the coniferous tree species that constitute potential hosts for a forest defoliator, the pine processionary moth Thaumetopoeapityocampa Den. & Schiff. (Lepidoptera, Notodontidae). We carried out an exhaustive inventory of all pines (Pinus spp.), cedars (Cedrus spp.) and Douglas-fir (Pseudotsugamenziesii) in a 22 × 22 km study window located in the open-field region of Beauce in the centre of France. We recorded a total of 3834 individuals or small groups host trees corresponding a density of 7.9 occurrences per 100 ha. We provide the spatial coordinates of the points without differentiation between tree species.
Mostrar más [+] Menos [-]An exhaustive inventory of coniferous trees in an agricultural landscape Texto completo
2015
Jérôme Rousselet | Alain Roques | Jacques Garcia | Jean-Pierre Rossi
Technical efficiency as a determinant of conversion to organic farming Texto completo
2015
Latruffe, Laure | Nauges, Celine | Desjeux, Yann | Structures et Marché Agricoles, Ressources et Territoires (SMART-LERECO) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | University of Southern Queensland (USQ)
Technical efficiency as a determinant of conversion to organic farming Texto completo
2015
Latruffe, Laure | Nauges, Celine | Desjeux, Yann | Structures et Marché Agricoles, Ressources et Territoires (SMART-LERECO) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | University of Southern Queensland (USQ)
Technical efficiency of farms under conventional agriculture determines whether farmsconvert to organic or remain in conventional farming. Efficient farms may be more capable ofadopting new technologies and therefore convert to organic farming. By contrast, choosing toproduce for the organic niche market may be a survival strategy for technically inefficientconventional farms.A study on French crop farms investigates technical efficiency during the years precedingconversion in order to predict the probability of conversion. The results show an influence oftechnical efficiency of (conventional) farms on the probability to convert to organic farming,but that the direction depends on farm-size and production-type.Another study on dairy farms from North West France considers the effect of (past)technological change on the decision to convert. Results show that dairy farms switching toorganic farming show a higher efficiency in conventional farming, but experienced aslowdown in efficiency the year before conversion.
Mostrar más [+] Menos [-]What role does climate change play in agricultural market uncertainty? An integrated assessment taking into account market-driven adjustments Texto completo
2015
Martínez Muñoz, Pilar | Blanco Fonseca, Maria | Van Doorslaer, Benjamin | Ramos, Fabien | Stanca Trufas, Lucian Emanuel
Recent studies point to climate change being one of the long-term drivers of agricultural market uncertainty. To advance in the understanding of the influence of climate change on future agricultural market developments, we compare a reference scenario for 2030 with alternative simulation scenarios that differ regarding: (1) emission scenarios; (2) climate projections; and (3) the consideration of carbon fertilization effects. For each simulation scenario, the CAPRI model provides global and EU-wide impacts of climate change on agricultural markets. Results show that climate change would considerably affect agrifood markets up to 2030. Nevertheless, market-driven adaptation strategies (production intensification, trade adjustments) would soften the impact of yield shocks on supply and demand. As a result, regional changes in production would be lower than foreseen by other studies focused on supply effects.
Mostrar más [+] Menos [-]Amphibian diversity increases in an heterogeneous agricultural landscape Texto completo
2015
Guerra, Cecília | Aráoz, Ezequiel
As a group amphibians are the vertebrates most affected by anthropic activity, particularly by agriculture. The rapid advance of the agricultural frontier makes it important to identify the role of agroecosystems as habitat supply for amphibians. We analyzed the differences in amphibian assemblages and populations between habitats with different plant covers and different degrees of human intervention in northwestern Argentina. For three years we conducted 114 high frequency trap samplings to quantify abundance, specific composition and species richness of amphibian assemblages in three habitat types (lemon and sugarcane crops and secondary forest) of a piedmont agroecosystem of Tucumán province. Crops hosted more species and individuals than secondary forests, but the specific composition of forest was different from that of crops suggesting that they could be complementary. Although the assemblage abundance of every observation responded to climate, the strong effect of sampling year was not related to climatic factors suggesting that there might be long term fluctuations that were not analyzed. We also found that responses to agricultural practices were species specific, so no generalizations about these practices should be done. Our study shows that cultivated areas are not hostile environments for amphibians since they can lodge huge amphibian populations and that the occurrence of disturbances associated to agricultural practices is not necessarily reflected in a decrease in the abundance and richness of amphibians in the short term. However, our results also show that forested lands are necessary to lodge some specialist species which are very rare in the croplands. This suggests that environmental heterogeneity generated by the combination of natural and cultivated patches can increase biodiversity at landscape scale because this allows the coexistence of species related to either kind of environment.
Mostrar más [+] Menos [-]Agricultural research in Ghana: An IFPRI-STEPRI report
2015
van Rheenen, Teunis; Obirth-Opareh, Nelson; Essegbey, George Owusu; Kolavalli, Shashidhara; Ferguson, Jenna; Boadu, Paul; Masahudu, Fuseni; Chiang, Catherine
PIC; DSGD | IFPRI1; GSSP; Theme 6; Subtheme 6.2; GRP32 | Working paper | Non-PR
Mostrar más [+] Menos [-]Modeling denitrification in an agricultural catchment in Central New York Texto completo
2015
Barclay, Janet R. | Anderson, Todd R. | Archibald, Josephine A. | Walter, M Todd
Denitrification, the microbially mediated reduction of NO3− to N2, NO, or N2O gas, provides an important ecosystem service by reducing N loads to downstream waters. To incorporate denitrification services into management planning, it is important to quantify the benefit; however, it is difficult to quantify denitrification rates and even harder to extrapolate them spatially and temporally to generate landscape-scale estimates of denitrification. We developed a coupled hydrologic-denitrification model that predicts daily denitrification rates across an agricultural watershed and calibrated it using in situ denitrification measurements and two types of hydrologic observations (streamflow and upland soil moisture). The model fits well with the observed denitrification (R2=0.77, RMSE=272kgNha−1yr−1, NRMSE=0.77), stream discharge (NSE=0.66) and soil moisture (NSE=0.77), and quantifies the denitrification ecosystem service provided by the watershed as a whole, as well as by the various land classes. Over the seven year model run, mean annual denitrification rates were 21kgNha−1yr−1 watershed-wide, 47kgNha−1yr−1 in the wetland, 52kgNha−1yr−1 in cropped areas, and 4kgNha−1yr−1 in pastures and forests. Quantification of ecosystem services is an essential prerequisite to accounting for those benefits in management decisions. This study is one step towards addressing the lack of field validated ecosystem service quantification studies. In the future, the model will allow us to further examine the spatial and temporal patterns of denitrification and to explore the implications of changes in management practices or climate.
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