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  • Publication . Article . 2022
    Open Access English
    Authors: 
    Quill R Kukla;
    Publisher: Oxford [u.a.] : Wiley-Blackwell
    Country: Germany

    When I say “I know Sarah,” or “I know Berlin,” what sort of knowledge am I claiming? Such knowledge of a particular is, I claim, not reducible to either propositional knowledge-that or to traditional physical know-how. Mere, bare knowledge by acquaintance also does not capture the kind of knowledge being claimed here. Using knowledge of a place as my central example, I argue that this kind of knowledge-of, or “objectual knowledge” as it is sometimes called, is of a distinctive epistemological sort. It is a genre of inherently first-personal aesthetic knowledge, but it also, like know-how, involves active skill. I end by exploring a couple of classic problems in aesthetic epistemology, applied to the case of knowledge-of as active aesthetic knowledge. © 2022 The Authors. European Journal of Philosophy published by John Wiley & Sons Ltd.

  • Open Access German
    Authors: 
    Hallfeldt, Jens;
    Publisher: Hannover : Universität
    Country: Germany

    [no abstract]

  • Open Access English
    Authors: 
    Ako, Mouhoube;
    Publisher: Hannover : Gottfried Wilhelm Leibniz Universität Hannover
    Country: Germany

    [no abstract]

  • Open Access English
    Authors: 
    Mamoudou Sétamou; Fritz Schulthess; Georg Goergen; Hans-Michael Poehling; Christian Borgemeister;
    Publisher: Cambridge : Cambridge University Press
    Country: Germany

    AbstractMussidia nigrivenella Ragonot is a pest of maize cobs in West Africa. It significantly reduces maize yields and grain quality, with quantitative losses of 2–25% at harvest, and up to 10–15% indirect losses due to an increase in storage pest infestation levels. Infestation by M. nigrivenella also significantly increased the susceptibility of maize to Aspergillus flavus infection and subsequent aflatoxin contamination. Surveys conducted in different agro-ecological zones of Benin on cultivated and wild host plants during 1994–1997 revealed one egg parasitoid, three larval parasitoids and one pupal parasitoid attacking M. nigrivenella. Egg parasitism was scarce on all host plants sampled and in all four agro-ecological zones. Parasitism by larval and pupal parasitoids was usually less than 10%, and varied with host plant species. Both larval and pupal parasitoids were rare or absent in cultivated maize fields. The solitary chalcidid pupal parasitoid, Antrocephalus crassipes Masi, was the predominant species, contributing approximately 53% of the observed mortality. Logistic regression analysis indicated that this parasitoid was more prevalent on fruits of Gardenia spp. (Rubiaceae) than on the other host plant species including maize used by M. nigrivenella, and was most abundant between February and September. The differences in parasitoid diversity and parasitism between Benin and other regions suggest that there are opportunities for biological control through introduction of exotic parasitoids or using the ‘new association’ approach, which uses natural enemies of closely related host species that occupy similar ecological niches to the target pest.

  • Open Access English
    Authors: 
    Steffanie Fromm; Jennifer Senkler; Holger Eubel; Christoph Peterhänsel; Hans-Peter Braun;
    Publisher: Oxford : Oxford Univ. Press
    Country: Germany

    The mitochondrial NADH dehydrogenase complex (complex I) is of particular importance for the respiratory chain in mitochondria. It is the major electron entry site for the mitochondrial electron transport chain (mETC) and therefore of great significance for mitochondrial ATP generation. We recently described an Arabidopsis thaliana double-mutant lacking the genes encoding the carbonic anhydrases CA1 and CA2, which both form part of a plant-specific ‘carbonic anhydrase domain’ of mitochondrial complex I. The mutant lacks complex I completely. Here we report extended analyses for systematically characterizing the proteome of the ca1ca2 mutant. Using various proteomic tools, we show that lack of complex I causes reorganization of the cellular respiration system. Reduced electron entry into the respiratory chain at the first segment of the mETC leads to induction of complexes II and IV as well as alternative oxidase. Increased electron entry at later segments of the mETC requires an increase in oxidation of organic substrates. This is reflected by higher abundance of proteins involved in glycolysis, the tricarboxylic acid cycle and branched-chain amino acid catabolism. Proteins involved in the light reaction of photosynthesis, the Calvin cycle, tetrapyrrole biosynthesis, and photorespiration are clearly reduced, contributing to the significant delay in growth and development of the double-mutant. Finally, enzymes involved in defense against reactive oxygen species and stress symptoms are much induced. These together with previously reported insights into the function of plant complex I, which were obtained by analysing other complex I mutants, are integrated in order to comprehensively describe ‘life without complex I’. Highlight Complex I dysfunction causes reorganization of cellular respiration and affects metabolic processes in mitochondria, plastids, peroxisomes, and other cellular compartments with drastic consequences for growth and development.

  • Publication . Article . Preprint . 2020
    Open Access English
    Authors: 
    William Cook; Iryna A. Glushchenko; Anna Ijjas; Frans Pretorius; Paul J. Steinhardt;
    Publisher: Amsterdam : Elsevier B.V.
    Country: Germany
    Project: NSF | Dynamical, Strong-Field G... (1912171)

    Performing a fully non-perturbative analysis using the tools of numerical general relativity, we demonstrate that a period of slow contraction is a `supersmoothing' cosmological phase that homogenizes, isotropizes and flattens the universe both classically and quantum mechanically and can do so far more robustly and rapidly than had been realized in earlier studies. Comment: 6 pages, 3 figures

  • Open Access English
    Authors: 
    Felix Zitzmann; Michael Rode;
    Publisher: Basel : MDPI
    Country: Germany

    In recent years, the impact of short-rotation coppice (SRC) on biodiversity has been a regular subject of research and ecological guidelines have been developed to make biomass cultivation on SRC more compatible with biodiversity concerns. However, since these guidelines are only implemented voluntarily by farmers, there are barely any SRC that are managed according to ecological guidelines. Consequently, knowledge about their importance for farmland biodiversity and about the impact of different measures for increasing biodiversity remains scarce. Therefore, three experimental SRC, which are managed according to ecological guidelines and thus include stands of different tree species (varieties of poplar (Populus) and willow (Salix), rowan (Sorbus aucuparia), silver birch (Betula pendula)) and different growth-stages within the same site, were investigated with regard to their importance as habitat for vascular plants. Species numbers and species composition were compared with the following habitat types: afforestations (AFO), young (HE-Y) and old hedges (HE-O), field margins (FM) and arable land (AL). Furthermore, different stand types (i.e., stands with different tree species and growth-stages, headlands, clearings) within these SRC were surveyed and compared. Species numbers of SRC were similar to HE-Y, AFO and FM and significantly higher than in AL and HE-O. The composition of plant communities in SRC differed considerably from the other farmland habitats, especially from AL, HE-O and FM. Within the SRC, most stand types had similar species numbers. Only the non-harvested poplar stands were particularly species-poor. Harvesting led to increased species numbers. This increase was significant for the poplar stands but only moderate for the willow stands. With regard to their species composition, the different stand types differed considerably in many cases. We conclude that SRC, which are managed according to ecological guidelines, can be an additional measure to promote phytodiversity in agricultural landscapes as they contain relatively high species numbers (of mainly common and adaptable species) and support distinct plant communities that differ from other farmland habitats. Therefore, measures such as the cultivation of different tree species or sectional harvesting could be offered as agri-environmental schemes to further increase the ecological sustainability of biomass production on SRC.

  • Publication . Other literature type . Article . Part of book or chapter of book . Conference object . 2016
    Open Access English
    Authors: 
    Topan, H.; Cam, A.; Özendi, M.; Oruç, M.; Jacobsen, Karsten; Taşkanat, T.; Halounova, L.; Šafář, V.; Toth, C.K.; Karas, J.; +14 more
    Publisher: Göttingen : Copernicus GmbH
    Countries: Turkey, Germany
    Project: TUBITAK | Yüksek Çözünürlüklü Optik... (114Y380)

    Pleiades 1A and 1B are twin optical satellites of Optical and Radar Federated Earth Observation (ORFEO) program jointly miming by France and Italy. They are the first satellites of Europe with sub-meter resolution. Airbus DS (formerly Astrium Geo) runs a MyGIC (formerly Pleiades Users Group) program to validate Pleiades images worldwide for various application purposes. The authors conduct three projects, one is within this program, the second is supported by BEU Scientific Research Project Program, and the third is supported by TUBITAK. Assessment of georeferencing accuracy, image quality, pansharpening performance and Digital Surface Model/Digital Terrain Model (DSM/DTM) quality subjects are investigated in these projects. For these purposes, triplet panchromatic (50 cm Ground Sampling Distance (GSD)) and VNIR (2 m GSD) Pleiades 1A images were investigated over Zonguldak test site (Turkey) which is urbanised, mountainous and covered by dense forest. The georeferencing accuracy was estimated with a standard deviation in X and Y (SX, SY) in the range of 0.45m by bias corrected Rational Polynomial Coefficient (RPC) orientation, using 170 Ground Control Points (GCPs). 3D standard deviation of +/- 0.44m in X, +/- 0.51m in Y, and +/- 1.82m in Z directions have been reached in spite of the very narrow angle of convergence by bias corrected RPC orientation. The image quality was also investigated with respect to effective resolution, Signal to Noise Ratio (SNR) and blur coefficient. The effective resolution was estimated with factor slightly below 1.0, meaning that the image quality corresponds to the nominal resolution of 50cm. The blur coefficients were achieved between 0.39-0.46 for triplet panchromatic images, indicating a satisfying image quality. SNR is in the range of other comparable space borne images which may be caused by de-noising of Pleiades images. The pansharpened images were generated by various methods, and are validated by most common statistical metrics and also visual interpretation. The generated DSM and DTM were achieved with +/- 1.6m standard deviation in Z (SZ) in relation to a reference DTM. Authors would like to thank to Airbus Defence and Space, BEU (Project ID: 2014-47912266-01), and TUBITAK (Project ID: 114Y380) for their support on the Pleiades projects. 23rd Congress of the International-Society-for-Photogrammetry-and-Remote-Sensing (ISPRS) -- JUL 12-19, 2016 -- Prague, CZECH REPUBLIC Airbus Defence and Space; BEU [2014-47912266-01]; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114Y380] Int Soc Photogrammetry & Remote Sensing WOS: 000392750100082

  • Open Access English
    Authors: 
    Walter, Jürgen; Hustedt, Michael; Stähr, Richard; Kaierle, Stefan; Jaeschke, Peter; Suttmann, Oliver; Overmeyer, Ludger;
    Publisher: Amsterdam : Elsevier B.V.
    Country: Germany

    Carbon fiber reinforced plastics (CFRP) show high potential for use in lightweight applications not only in aircraft design, but also in the automotive or wind energy industry. However, processing of CFRP is complex and expensive due to their outstanding mechanical properties. One possibility to manufacture CFRP structures flexibly at acceptable process speeds is high-power laser cutting. Though showing various advantages such as contactless energy transfer, this process is connected to potentially hazardous emission of respirable dust and organic gases. Moreover, the emitted particles may be fibrous, thus requiring particular attention. Here, a systematic analysis of the hazardous substances emitted during laser cutting of CFRP with thermoplastic and thermosetting matrix is presented. The objective is to evaluate emission rates for the total particulate and gaseous fractions as well as for different organic key components. Furthermore, the influence of the laser process conditions shall be assessed, and first proposals to handle the emissions adequately are made.

  • Open Access English
    Authors: 
    Trung Thanh Nguyen; Bauer, Siegfried; Grote, Ulrike;
    Publisher: MDPI AG
    Country: Germany

    Facing widespread poverty and land degradation, Vietnam started a land reform in 1993 as part of its renovation policy package known as “Doi Moi”. This paper examines the impacts of improved land tenure security, via this land reform, on manure use by farm households. As manure potentially improves soil fertility by adding organic matter and nutrients to the soil surface, it might contribute to improving soil productive capacity and reversing land degradation. Random effect regression models are applied to a panel dataset of 133 farm households in the Northern Uplands of Vietnam collected in 1993, 1998, and 2006. The results confirm that land tenure security has positive effects on manure use, but the levels of influence differ depending on whether the land has been privatized or whether the land title has already been issued. In addition, manure use is also influenced by the number of cattle and pigs, the education level and ethnicity of household heads, farm land size and non-farm income. The findings suggest that speeding up land privatization and titling, encouraging cattle and pig rearing, and improving education would promote manure use in farm production. However, careful interpretation of our research findings is required as land privatization, together with economic growth and population pressure, might lead to overuse of farm inputs. DFG

Advanced search in
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arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
12,848 Research products, page 1 of 1,285
  • Publication . Article . 2022
    Open Access English
    Authors: 
    Quill R Kukla;
    Publisher: Oxford [u.a.] : Wiley-Blackwell
    Country: Germany

    When I say “I know Sarah,” or “I know Berlin,” what sort of knowledge am I claiming? Such knowledge of a particular is, I claim, not reducible to either propositional knowledge-that or to traditional physical know-how. Mere, bare knowledge by acquaintance also does not capture the kind of knowledge being claimed here. Using knowledge of a place as my central example, I argue that this kind of knowledge-of, or “objectual knowledge” as it is sometimes called, is of a distinctive epistemological sort. It is a genre of inherently first-personal aesthetic knowledge, but it also, like know-how, involves active skill. I end by exploring a couple of classic problems in aesthetic epistemology, applied to the case of knowledge-of as active aesthetic knowledge. © 2022 The Authors. European Journal of Philosophy published by John Wiley & Sons Ltd.

  • Open Access German
    Authors: 
    Hallfeldt, Jens;
    Publisher: Hannover : Universität
    Country: Germany

    [no abstract]

  • Open Access English
    Authors: 
    Ako, Mouhoube;
    Publisher: Hannover : Gottfried Wilhelm Leibniz Universität Hannover
    Country: Germany

    [no abstract]

  • Open Access English
    Authors: 
    Mamoudou Sétamou; Fritz Schulthess; Georg Goergen; Hans-Michael Poehling; Christian Borgemeister;
    Publisher: Cambridge : Cambridge University Press
    Country: Germany

    AbstractMussidia nigrivenella Ragonot is a pest of maize cobs in West Africa. It significantly reduces maize yields and grain quality, with quantitative losses of 2–25% at harvest, and up to 10–15% indirect losses due to an increase in storage pest infestation levels. Infestation by M. nigrivenella also significantly increased the susceptibility of maize to Aspergillus flavus infection and subsequent aflatoxin contamination. Surveys conducted in different agro-ecological zones of Benin on cultivated and wild host plants during 1994–1997 revealed one egg parasitoid, three larval parasitoids and one pupal parasitoid attacking M. nigrivenella. Egg parasitism was scarce on all host plants sampled and in all four agro-ecological zones. Parasitism by larval and pupal parasitoids was usually less than 10%, and varied with host plant species. Both larval and pupal parasitoids were rare or absent in cultivated maize fields. The solitary chalcidid pupal parasitoid, Antrocephalus crassipes Masi, was the predominant species, contributing approximately 53% of the observed mortality. Logistic regression analysis indicated that this parasitoid was more prevalent on fruits of Gardenia spp. (Rubiaceae) than on the other host plant species including maize used by M. nigrivenella, and was most abundant between February and September. The differences in parasitoid diversity and parasitism between Benin and other regions suggest that there are opportunities for biological control through introduction of exotic parasitoids or using the ‘new association’ approach, which uses natural enemies of closely related host species that occupy similar ecological niches to the target pest.

  • Open Access English
    Authors: 
    Steffanie Fromm; Jennifer Senkler; Holger Eubel; Christoph Peterhänsel; Hans-Peter Braun;
    Publisher: Oxford : Oxford Univ. Press
    Country: Germany

    The mitochondrial NADH dehydrogenase complex (complex I) is of particular importance for the respiratory chain in mitochondria. It is the major electron entry site for the mitochondrial electron transport chain (mETC) and therefore of great significance for mitochondrial ATP generation. We recently described an Arabidopsis thaliana double-mutant lacking the genes encoding the carbonic anhydrases CA1 and CA2, which both form part of a plant-specific ‘carbonic anhydrase domain’ of mitochondrial complex I. The mutant lacks complex I completely. Here we report extended analyses for systematically characterizing the proteome of the ca1ca2 mutant. Using various proteomic tools, we show that lack of complex I causes reorganization of the cellular respiration system. Reduced electron entry into the respiratory chain at the first segment of the mETC leads to induction of complexes II and IV as well as alternative oxidase. Increased electron entry at later segments of the mETC requires an increase in oxidation of organic substrates. This is reflected by higher abundance of proteins involved in glycolysis, the tricarboxylic acid cycle and branched-chain amino acid catabolism. Proteins involved in the light reaction of photosynthesis, the Calvin cycle, tetrapyrrole biosynthesis, and photorespiration are clearly reduced, contributing to the significant delay in growth and development of the double-mutant. Finally, enzymes involved in defense against reactive oxygen species and stress symptoms are much induced. These together with previously reported insights into the function of plant complex I, which were obtained by analysing other complex I mutants, are integrated in order to comprehensively describe ‘life without complex I’. Highlight Complex I dysfunction causes reorganization of cellular respiration and affects metabolic processes in mitochondria, plastids, peroxisomes, and other cellular compartments with drastic consequences for growth and development.

  • Publication . Article . Preprint . 2020
    Open Access English
    Authors: 
    William Cook; Iryna A. Glushchenko; Anna Ijjas; Frans Pretorius; Paul J. Steinhardt;
    Publisher: Amsterdam : Elsevier B.V.
    Country: Germany
    Project: NSF | Dynamical, Strong-Field G... (1912171)

    Performing a fully non-perturbative analysis using the tools of numerical general relativity, we demonstrate that a period of slow contraction is a `supersmoothing' cosmological phase that homogenizes, isotropizes and flattens the universe both classically and quantum mechanically and can do so far more robustly and rapidly than had been realized in earlier studies. Comment: 6 pages, 3 figures

  • Open Access English
    Authors: 
    Felix Zitzmann; Michael Rode;
    Publisher: Basel : MDPI
    Country: Germany

    In recent years, the impact of short-rotation coppice (SRC) on biodiversity has been a regular subject of research and ecological guidelines have been developed to make biomass cultivation on SRC more compatible with biodiversity concerns. However, since these guidelines are only implemented voluntarily by farmers, there are barely any SRC that are managed according to ecological guidelines. Consequently, knowledge about their importance for farmland biodiversity and about the impact of different measures for increasing biodiversity remains scarce. Therefore, three experimental SRC, which are managed according to ecological guidelines and thus include stands of different tree species (varieties of poplar (Populus) and willow (Salix), rowan (Sorbus aucuparia), silver birch (Betula pendula)) and different growth-stages within the same site, were investigated with regard to their importance as habitat for vascular plants. Species numbers and species composition were compared with the following habitat types: afforestations (AFO), young (HE-Y) and old hedges (HE-O), field margins (FM) and arable land (AL). Furthermore, different stand types (i.e., stands with different tree species and growth-stages, headlands, clearings) within these SRC were surveyed and compared. Species numbers of SRC were similar to HE-Y, AFO and FM and significantly higher than in AL and HE-O. The composition of plant communities in SRC differed considerably from the other farmland habitats, especially from AL, HE-O and FM. Within the SRC, most stand types had similar species numbers. Only the non-harvested poplar stands were particularly species-poor. Harvesting led to increased species numbers. This increase was significant for the poplar stands but only moderate for the willow stands. With regard to their species composition, the different stand types differed considerably in many cases. We conclude that SRC, which are managed according to ecological guidelines, can be an additional measure to promote phytodiversity in agricultural landscapes as they contain relatively high species numbers (of mainly common and adaptable species) and support distinct plant communities that differ from other farmland habitats. Therefore, measures such as the cultivation of different tree species or sectional harvesting could be offered as agri-environmental schemes to further increase the ecological sustainability of biomass production on SRC.

  • Publication . Other literature type . Article . Part of book or chapter of book . Conference object . 2016
    Open Access English
    Authors: 
    Topan, H.; Cam, A.; Özendi, M.; Oruç, M.; Jacobsen, Karsten; Taşkanat, T.; Halounova, L.; Šafář, V.; Toth, C.K.; Karas, J.; +14 more
    Publisher: Göttingen : Copernicus GmbH
    Countries: Turkey, Germany
    Project: TUBITAK | Yüksek Çözünürlüklü Optik... (114Y380)

    Pleiades 1A and 1B are twin optical satellites of Optical and Radar Federated Earth Observation (ORFEO) program jointly miming by France and Italy. They are the first satellites of Europe with sub-meter resolution. Airbus DS (formerly Astrium Geo) runs a MyGIC (formerly Pleiades Users Group) program to validate Pleiades images worldwide for various application purposes. The authors conduct three projects, one is within this program, the second is supported by BEU Scientific Research Project Program, and the third is supported by TUBITAK. Assessment of georeferencing accuracy, image quality, pansharpening performance and Digital Surface Model/Digital Terrain Model (DSM/DTM) quality subjects are investigated in these projects. For these purposes, triplet panchromatic (50 cm Ground Sampling Distance (GSD)) and VNIR (2 m GSD) Pleiades 1A images were investigated over Zonguldak test site (Turkey) which is urbanised, mountainous and covered by dense forest. The georeferencing accuracy was estimated with a standard deviation in X and Y (SX, SY) in the range of 0.45m by bias corrected Rational Polynomial Coefficient (RPC) orientation, using 170 Ground Control Points (GCPs). 3D standard deviation of +/- 0.44m in X, +/- 0.51m in Y, and +/- 1.82m in Z directions have been reached in spite of the very narrow angle of convergence by bias corrected RPC orientation. The image quality was also investigated with respect to effective resolution, Signal to Noise Ratio (SNR) and blur coefficient. The effective resolution was estimated with factor slightly below 1.0, meaning that the image quality corresponds to the nominal resolution of 50cm. The blur coefficients were achieved between 0.39-0.46 for triplet panchromatic images, indicating a satisfying image quality. SNR is in the range of other comparable space borne images which may be caused by de-noising of Pleiades images. The pansharpened images were generated by various methods, and are validated by most common statistical metrics and also visual interpretation. The generated DSM and DTM were achieved with +/- 1.6m standard deviation in Z (SZ) in relation to a reference DTM. Authors would like to thank to Airbus Defence and Space, BEU (Project ID: 2014-47912266-01), and TUBITAK (Project ID: 114Y380) for their support on the Pleiades projects. 23rd Congress of the International-Society-for-Photogrammetry-and-Remote-Sensing (ISPRS) -- JUL 12-19, 2016 -- Prague, CZECH REPUBLIC Airbus Defence and Space; BEU [2014-47912266-01]; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114Y380] Int Soc Photogrammetry & Remote Sensing WOS: 000392750100082

  • Open Access English
    Authors: 
    Walter, Jürgen; Hustedt, Michael; Stähr, Richard; Kaierle, Stefan; Jaeschke, Peter; Suttmann, Oliver; Overmeyer, Ludger;
    Publisher: Amsterdam : Elsevier B.V.
    Country: Germany

    Carbon fiber reinforced plastics (CFRP) show high potential for use in lightweight applications not only in aircraft design, but also in the automotive or wind energy industry. However, processing of CFRP is complex and expensive due to their outstanding mechanical properties. One possibility to manufacture CFRP structures flexibly at acceptable process speeds is high-power laser cutting. Though showing various advantages such as contactless energy transfer, this process is connected to potentially hazardous emission of respirable dust and organic gases. Moreover, the emitted particles may be fibrous, thus requiring particular attention. Here, a systematic analysis of the hazardous substances emitted during laser cutting of CFRP with thermoplastic and thermosetting matrix is presented. The objective is to evaluate emission rates for the total particulate and gaseous fractions as well as for different organic key components. Furthermore, the influence of the laser process conditions shall be assessed, and first proposals to handle the emissions adequately are made.

  • Open Access English
    Authors: 
    Trung Thanh Nguyen; Bauer, Siegfried; Grote, Ulrike;
    Publisher: MDPI AG
    Country: Germany

    Facing widespread poverty and land degradation, Vietnam started a land reform in 1993 as part of its renovation policy package known as “Doi Moi”. This paper examines the impacts of improved land tenure security, via this land reform, on manure use by farm households. As manure potentially improves soil fertility by adding organic matter and nutrients to the soil surface, it might contribute to improving soil productive capacity and reversing land degradation. Random effect regression models are applied to a panel dataset of 133 farm households in the Northern Uplands of Vietnam collected in 1993, 1998, and 2006. The results confirm that land tenure security has positive effects on manure use, but the levels of influence differ depending on whether the land has been privatized or whether the land title has already been issued. In addition, manure use is also influenced by the number of cattle and pigs, the education level and ethnicity of household heads, farm land size and non-farm income. The findings suggest that speeding up land privatization and titling, encouraging cattle and pig rearing, and improving education would promote manure use in farm production. However, careful interpretation of our research findings is required as land privatization, together with economic growth and population pressure, might lead to overuse of farm inputs. DFG

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