Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa
Identifieur interne : 001874 ( Istex/Corpus ); précédent : 001873; suivant : 001875Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa
Auteurs : George A. KeyaSource :
- Acta Oecologica [ 1146-609X ] ; 1997.
English descriptors
- KwdEn :
Abstract
Abstract: Indigofera spinosa (Forsk.) is a key forage resource in the arid rangelands of northern Kenya inhabited by nomadic pastoralists. Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that I. spinosa is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of I. spinosa pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. Yield to browsers will also be optimised at this level of impact.
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DOI: 10.1016/S1146-609X(97)80034-3
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<record><TEI wicri:istexFullTextTei="biblStruct"><teiHeader><fileDesc><titleStmt><title xml:lang="en">Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa</title><author><name sortKey="Keya, George A" sort="Keya, George A" uniqKey="Keya G" first="George A." last="Keya">George A. Keya</name><affiliation><mods:affiliation>National Arid Lands Research Centre, PO Box 147, Marsabit, Kenya</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA</idno><date when="1997" year="1997">1997</date><idno type="doi">10.1016/S1146-609X(97)80034-3</idno><idno type="url">https://api.istex.fr/document/93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">001874</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001874</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a" type="main" xml:lang="en">Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa</title><author><name sortKey="Keya, George A" sort="Keya, George A" uniqKey="Keya G" first="George A." last="Keya">George A. Keya</name><affiliation><mods:affiliation>National Arid Lands Research Centre, PO Box 147, Marsabit, Kenya</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j">Acta Oecologica</title><title level="j" type="abbrev">ACTOEC</title><idno type="ISSN">1146-609X</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1997">1997</date><biblScope unit="volume">18</biblScope><biblScope unit="issue">4</biblScope><biblScope unit="page" from="449">449</biblScope><biblScope unit="page" to="463">463</biblScope></imprint><idno type="ISSN">1146-609X</idno></series><idno type="istex">93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA</idno><idno type="DOI">10.1016/S1146-609X(97)80034-3</idno><idno type="PII">S1146-609X(97)80034-3</idno><idno type="ArticleID">97800343</idno></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">1146-609X</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Indigofera spinosa</term><term>Marsabit</term><term>Rendille</term><term>defoliation</term><term>northern Kenya</term><term>pastoralists</term><term>reproduction</term><term>yield</term></keywords></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">Abstract: Indigofera spinosa (Forsk.) is a key forage resource in the arid rangelands of northern Kenya inhabited by nomadic pastoralists. Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that I. spinosa is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of I. spinosa pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. Yield to browsers will also be optimised at this level of impact.</div></front></TEI><istex><corpusName>elsevier</corpusName><author><json:item><name>George A. 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Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that I. spinosa is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of I. spinosa pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. 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Report B-3</title></serie><host><volume>18</volume><pii><json:string>S1146-609X(97)X8030-0</json:string></pii><pages><last>463</last><first>449</first></pages><issn><json:string>1146-609X</json:string></issn><issue>4</issue><genre><json:string>journal</json:string></genre><language><json:string>unknown</json:string></language><title>Acta Oecologica</title><publicationDate>1997</publicationDate></host><categories><wos><json:string>science</json:string><json:string>ecology</json:string></wos><scienceMetrix><json:string>natural sciences</json:string><json:string>biology</json:string><json:string>ecology</json:string></scienceMetrix></categories><publicationDate>1997</publicationDate><copyrightDate>1997</copyrightDate><doi><json:string>10.1016/S1146-609X(97)80034-3</json:string></doi><id>93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA</id><score>0.034119345</score><fulltext><json:item><extension>pdf</extension><original>true</original><mimetype>application/pdf</mimetype><uri>https://api.istex.fr/document/93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA/fulltext/pdf</uri></json:item><json:item><extension>zip</extension><original>false</original><mimetype>application/zip</mimetype><uri>https://api.istex.fr/document/93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA/fulltext/zip</uri></json:item><istex:fulltextTEI uri="https://api.istex.fr/document/93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA/fulltext/tei"><teiHeader><fileDesc><titleStmt><title level="a" type="main" xml:lang="en">Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa</title></titleStmt><publicationStmt><authority>ISTEX</authority><publisher>ELSEVIER</publisher><availability><p>©1997 Gauthier-Villars</p></availability><date>1997</date></publicationStmt><sourceDesc><biblStruct type="inbook"><analytic><title level="a" type="main" xml:lang="en">Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa</title><author xml:id="author-1"><persName><forename type="first">George A.</forename><surname>Keya</surname></persName><note type="biography">Present address: c/o Dr. B. Hornetz, Department of Geography and Goesciences, University of Trier, PO Box 3825, D-54286, Trier, Germany.</note><affiliation>Present address: c/o Dr. B. Hornetz, Department of Geography and Goesciences, University of Trier, PO Box 3825, D-54286, Trier, Germany.</affiliation><affiliation>National Arid Lands Research Centre, PO Box 147, Marsabit, Kenya</affiliation></author></analytic><monogr><title level="j">Acta Oecologica</title><title level="j" type="abbrev">ACTOEC</title><idno type="pISSN">1146-609X</idno><idno type="PII">S1146-609X(97)X8030-0</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1997"></date><biblScope unit="volume">18</biblScope><biblScope unit="issue">4</biblScope><biblScope unit="page" from="449">449</biblScope><biblScope unit="page" to="463">463</biblScope></imprint></monogr><idno type="istex">93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA</idno><idno type="DOI">10.1016/S1146-609X(97)80034-3</idno><idno type="PII">S1146-609X(97)80034-3</idno><idno type="ArticleID">97800343</idno></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>1997</date></creation><langUsage><language ident="en">en</language></langUsage><abstract xml:lang="en"><p>Abstract: Indigofera spinosa (Forsk.) is a key forage resource in the arid rangelands of northern Kenya inhabited by nomadic pastoralists. Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that I. spinosa is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of I. spinosa pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. Yield to browsers will also be optimised at this level of impact.</p></abstract><abstract xml:lang="fr"><p>Résumé: Indigofera spinosa (Forsk.) est une ressource fourragère clef des parcours arides du nord du Kenya, où vivent des pasteurs nomades. Sa saveur étant très appréciée par le bétail, I. spinosa est soumise, périodiquement et, par endroits en permanence, à un fort impact du broutement partout où elle pousse. Cette étude évalue les effets d'une herbivorie simulée sur le rendement et la reproduction de cette espèce. Différents niveaux d'impact (léger, modéré, modéré à important, important) ont été infligés à des arbustes, à des intervalles de 15 jours et un mois respectivement. Les résultats indiquent que I. spinosa présente une forte résilience au broutement. La compensation maximale en repousse est atteinte pour le niveau d'impact modéré. Une taille importante réduit la masse résiduelle à un point qui restreint sévèrement la possibilité de compenser la perte des organes végétatifs. Un intervalle plus grand entre les tailles a tendance à améliorer la repousse, en particulier pour une intensité de taille modérée. La reproduction est significativement réduite par l'impact de la taille. Pour une taille importante, la reproduction est complètement arrêtée. L'irrigation atténue l'impact de la taille par une augmentation de la repousse et de l'activité reproductrice. Afin d'optimiser la production et l'utilisation des herbages à I. spinosa au cours des saisons (humides) de croissance, un pâturage modéré est recommendé, qui laisse une hauteur de pâture de 10 à 15 cm. A cette intensité, une reproduction adéquate sera stimulée, et assurée la disponibilité d'une masse résiduelle, critique pour l'affouragement en période sèche et pour une production durable à long terme. La production pour les troupeaux sera également optimisée à ce niveau d'impact.</p></abstract><textClass xml:lang="en"><keywords scheme="keyword"><list><head>Keywords</head><item><term>Indigofera spinosa</term></item><item><term>defoliation</term></item><item><term>yield</term></item><item><term>reproduction</term></item><item><term>northern Kenya</term></item><item><term>Marsabit</term></item><item><term>Rendille</term></item><item><term>pastoralists</term></item></list></keywords></textClass></profileDesc><revisionDesc><change when="1997">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Elsevier doc found" wicri:toSee="Elsevier, no converted or simple article"><istex:xmlDeclaration>version="1.0" encoding="utf-8"</istex:xmlDeclaration><istex:docType PUBLIC="-//ES//DTD journal article DTD version 5.0.1//EN//XML" URI="art501.dtd" name="istex:docType"></istex:docType><istex:document><article version="5.0" xml:lang="en" docsubtype="fla"><item-info><jid>ACTOEC</jid><aid>97800343</aid><ce:pii>S1146-609X(97)80034-3</ce:pii><ce:doi>10.1016/S1146-609X(97)80034-3</ce:doi><ce:copyright type="unknown" year="1997">Gauthier-Villars</ce:copyright></item-info><head><ce:title>Effects of defoliation on yield and reproduction of the dwarf shrub <ce:italic>Indigofera spinosa</ce:italic></ce:title><ce:author-group><ce:author><ce:given-name>George A.</ce:given-name><ce:surname>Keya</ce:surname><ce:cross-ref refid="fn1"><ce:sup>(1)</ce:sup></ce:cross-ref></ce:author><ce:affiliation id="aff1"><ce:textfn>National Arid Lands Research Centre, PO Box 147, Marsabit, Kenya</ce:textfn></ce:affiliation><ce:footnote id="fn1"><ce:label>(1)</ce:label><ce:note-para>Present address: <ce:italic>c/o Dr. B. Hornetz, Department of Geography and Goesciences, University of Trier, PO Box 3825, D-54286, Trier, Germany</ce:italic>.</ce:note-para></ce:footnote></ce:author-group><ce:date-received day="26" month="9" year="1996"></ce:date-received><ce:date-accepted day="3" month="2" year="1997"></ce:date-accepted><ce:abstract id="ab1" class="author" xml:lang="en"><ce:section-title>Abstract</ce:section-title><ce:abstract-sec><ce:simple-para><ce:italic>Indigofera spinosa</ce:italic> (Forsk.) is a key forage resource in the arid rangelands of northern Kenya inhabited by nomadic pastoralists. Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that <ce:italic>I. spinosa</ce:italic> is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of <ce:italic>I. spinosa</ce:italic> pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. Yield to browsers will also be optimised at this level of impact.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract id="ab2" class="author" xml:lang="fr"><ce:section-title>Résumé</ce:section-title><ce:abstract-sec><ce:simple-para><ce:italic>Indigofera spinosa</ce:italic> (Forsk.) est une ressource fourragère clef des parcours arides du nord du Kenya, où vivent des pasteurs nomades. Sa saveur étant très appréciée par le bétail, <ce:italic>I. spinosa</ce:italic> est soumise, périodiquement et, par endroits en permanence, à un fort impact du broutement partout où elle pousse. Cette étude évalue les effets d'une herbivorie simulée sur le rendement et la reproduction de cette espèce. Différents niveaux d'impact (léger, modéré, modéré à important, important) ont été infligés à des arbustes, à des intervalles de 15 jours et un mois respectivement. Les résultats indiquent que <ce:italic>I. spinosa</ce:italic> présente une forte résilience au broutement. La compensation maximale en repousse est atteinte pour le niveau d'impact modéré. Une taille importante réduit la masse résiduelle à un point qui restreint sévèrement la possibilité de compenser la perte des organes végétatifs. Un intervalle plus grand entre les tailles a tendance à améliorer la repousse, en particulier pour une intensité de taille modérée. La reproduction est significativement réduite par l'impact de la taille. Pour une taille importante, la reproduction est complètement arrêtée. L'irrigation atténue l'impact de la taille par une augmentation de la repousse et de l'activité reproductrice. Afin d'optimiser la production et l'utilisation des herbages à <ce:italic>I. spinosa</ce:italic> au cours des saisons (humides) de croissance, un pâturage modéré est recommendé, qui laisse une hauteur de pâture de 10 à 15 cm. A cette intensité, une reproduction adéquate sera stimulée, et assurée la disponibilité d'une masse résiduelle, critique pour l'affouragement en période sèche et pour une production durable à long terme. La production pour les troupeaux sera également optimisée à ce niveau d'impact.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:keywords class="keyword" xml:lang="en"><ce:section-title>Keywords</ce:section-title><ce:keyword><ce:text><ce:italic>Indigofera spinosa</ce:italic></ce:text></ce:keyword><ce:keyword><ce:text>defoliation</ce:text></ce:keyword><ce:keyword><ce:text>yield</ce:text></ce:keyword><ce:keyword><ce:text>reproduction</ce:text></ce:keyword><ce:keyword><ce:text>northern Kenya</ce:text></ce:keyword><ce:keyword><ce:text>Marsabit</ce:text></ce:keyword><ce:keyword><ce:text>Rendille</ce:text></ce:keyword><ce:keyword><ce:text>pastoralists</ce:text></ce:keyword></ce:keywords></head><tail><ce:bibliography><ce:section-title>References</ce:section-title><ce:bibliography-sec><ce:bib-reference id="bib1"><ce:label>Bake, 1983</ce:label><sb:reference><sb:contribution langtype="en"><sb:authors><sb:author><ce:surname>Bake</ce:surname><ce:given-name>G.</ce:given-name></sb:author></sb:authors><sb:title><sb:maintitle>An analysis of climatological data from Marsabit District of Northern Kenya</sb:maintitle></sb:title></sb:contribution><sb:host><sb:edited-book><sb:book-series><sb:series><sb:title><sb:maintitle>IPAL Tech. 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Kulal marsabit Area</sb:maintitle></sb:title></sb:series></sb:book-series><sb:date>1986</sb:date><sb:publisher><sb:name>Ministry of Agriculture and Livestock Development (MOLD)</sb:name><sb:location>Nairobi Kenya</sb:location></sb:publisher></sb:edited-book><sb:pages><sb:first-page>268</sb:first-page></sb:pages></sb:host></sb:reference></ce:bib-reference></ce:bibliography-sec></ce:bibliography></tail></article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Effects of defoliation on yield and reproduction of the dwarf shrub Indigofera spinosa</title></titleInfo><titleInfo type="alternative" lang="en" contentType="CDATA"><title>Effects of defoliation on yield and reproduction of the dwarf shrub</title></titleInfo><name type="personal"><namePart type="given">George A.</namePart><namePart type="family">Keya</namePart><affiliation>National Arid Lands Research Centre, PO Box 147, Marsabit, Kenya</affiliation><description>Present address: c/o Dr. B. Hornetz, Department of Geography and Goesciences, University of Trier, PO Box 3825, D-54286, Trier, Germany.</description><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="Full-length article"></genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">1997</dateIssued><copyrightDate encoding="w3cdtf">1997</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType></physicalDescription><abstract lang="en">Abstract: Indigofera spinosa (Forsk.) is a key forage resource in the arid rangelands of northern Kenya inhabited by nomadic pastoralists. Because it is highly relished by livestock, it is subjected to heavy periodic and in some areas permanent browsing impact wherever it occurs. This study evaluated the effects of simulated herbivory on yield and reproduction of this species. Different levels of impact (light, moderate, moderately-heavy and heavy) were inflicted on individual shrubs at fortnightly and monthly intervals respectively. Results indicate that I. spinosa is highly resilient to browsing. Maximum regrowth compensation was achieved at the moderate level of impact. Heavy clipping reduced residual mass to an extend whereby the ability to compensate for lost vegetative organs was severely curtailed. A longer clipping interval tended to enhance regrowth, especially at the moderate intensity. Reproduction was significantly reduced by clipping impact. At the heavy clipping impact, reproduction was completely halted. Irrigation mitigated the impact of clipping by increasing the amount of regrowth and reproductive activity. To optimise the production and utilisation of I. spinosa pastures during the growing (wet) seasons, it is recommended that grazing should be moderate to leave browse height of 10–15 cm. At this intensity, adequate reproduction will be stimulated while ensuring availability of residual mass critical for dry season feeding and long term sustainable production. Yield to browsers will also be optimised at this level of impact.</abstract><abstract lang="fr">Résumé: Indigofera spinosa (Forsk.) est une ressource fourragère clef des parcours arides du nord du Kenya, où vivent des pasteurs nomades. Sa saveur étant très appréciée par le bétail, I. spinosa est soumise, périodiquement et, par endroits en permanence, à un fort impact du broutement partout où elle pousse. Cette étude évalue les effets d'une herbivorie simulée sur le rendement et la reproduction de cette espèce. Différents niveaux d'impact (léger, modéré, modéré à important, important) ont été infligés à des arbustes, à des intervalles de 15 jours et un mois respectivement. Les résultats indiquent que I. spinosa présente une forte résilience au broutement. La compensation maximale en repousse est atteinte pour le niveau d'impact modéré. Une taille importante réduit la masse résiduelle à un point qui restreint sévèrement la possibilité de compenser la perte des organes végétatifs. Un intervalle plus grand entre les tailles a tendance à améliorer la repousse, en particulier pour une intensité de taille modérée. La reproduction est significativement réduite par l'impact de la taille. Pour une taille importante, la reproduction est complètement arrêtée. L'irrigation atténue l'impact de la taille par une augmentation de la repousse et de l'activité reproductrice. Afin d'optimiser la production et l'utilisation des herbages à I. spinosa au cours des saisons (humides) de croissance, un pâturage modéré est recommendé, qui laisse une hauteur de pâture de 10 à 15 cm. A cette intensité, une reproduction adéquate sera stimulée, et assurée la disponibilité d'une masse résiduelle, critique pour l'affouragement en période sèche et pour une production durable à long terme. La production pour les troupeaux sera également optimisée à ce niveau d'impact.</abstract><subject lang="en"><genre>Keywords</genre><topic>Indigofera spinosa</topic><topic>defoliation</topic><topic>yield</topic><topic>reproduction</topic><topic>northern Kenya</topic><topic>Marsabit</topic><topic>Rendille</topic><topic>pastoralists</topic></subject><relatedItem type="host"><titleInfo><title>Acta Oecologica</title></titleInfo><titleInfo type="abbreviated"><title>ACTOEC</title></titleInfo><genre type="journal">journal</genre><originInfo><dateIssued encoding="w3cdtf">1997</dateIssued></originInfo><identifier type="ISSN">1146-609X</identifier><identifier type="PII">S1146-609X(97)X8030-0</identifier><part><date>1997</date><detail type="volume"><number>18</number><caption>vol.</caption></detail><detail type="issue"><number>4</number><caption>no.</caption></detail><extent unit="issue pages"><start>383</start><end>517</end></extent><extent unit="pages"><start>449</start><end>463</end></extent></part></relatedItem><identifier type="istex">93766B3122F37DA3C280ABE26B41AC8EDA1E3DBA</identifier><identifier type="DOI">10.1016/S1146-609X(97)80034-3</identifier><identifier type="PII">S1146-609X(97)80034-3</identifier><identifier type="ArticleID">97800343</identifier><accessCondition type="use and reproduction" contentType="copyright">©1997 Gauthier-Villars</accessCondition><recordInfo><recordContentSource>ELSEVIER</recordContentSource><recordOrigin>Gauthier-Villars, ©1997</recordOrigin></recordInfo></mods></metadata></istex></record>Pour manipuler ce document sous Unix (Dilib)
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