<p>Oil palm (<i>Elaeis guineensis</i> Jacq.) is the world’s leading source of vegetable oil and an important driver of rural economic activity in Southeast Asia, West Africa, and the equatorial region of Latin America. In the Llanos region of Colombia, palm oil production is additionally an important vehicle for legal employment and social stability in a region deeply affected by the country’s longstanding and recently-concluded armed conflict. The economic viability of palm oil production is thus of great interest to both those directly employed in the industry and to the larger society around them, and yet oil palm remains a relatively understudied cropping system.</p> <p>Spending on fertilizer is one of the largest costs in palm oil production, and plantations face considerable pressure to apply fertilizer as efficiently as possible in order to maintain the profitability of their operations. However, developing strategies for optimizing fertilizer applications in oil palm can be considerably challenging given the particular characteristics of palm oil production systems. Oil palm has a typical life-cycle of 25 years, with harvesting done manually approximately every fifteen days for the duration of the palms productive life-cycle. The morphology of oil palm’s reproductive system makes it possible for environmental changes to affect yield in irregular ways, with the same soil or climate-related stressors having the potential to affect yields either immediately or multiple years after the event. It can therefore be difficult for plantations to link changes in yield patterns to individual management changes or environmental factors. Additionally, since unlike all other major oilseeds oil palms must be harvested manually, plantation managers do not have access to the kind of detailed yield data made possible by mechanized harvesting equipment, but must rely on much more irregular and coarser-resolution information to examine yield variability within plantations. Understanding how the particular soil conditions and fertilizer management history of an individual oil palm plantation drive variability in yields requires employing innovative approaches to maximize the insights to be learned from the available data. </p> <p> For this study, we worked with a 5,220 hectare oil palm plantation in the Colombian Llanos, in the municipality of Villanueva, Casanare. Despite uniform fertilizer applications and management practices, along with uniform climatic conditions within the plantation, significant yield variability existed within the plantation, with plantation managers initially unable to determine the underlying causes. We proposed and evaluated a methodology for using digital terrain and soil mapping for generating continuous soil data within an oil palm production system, based on Functional Soil Mapping (FSM) methods using the SRTM Global Digital Elevation model and geo-referenced soil sampling, with the goal of identifying soil physical, chemical and hydrological properties that could be directly linked to different yield responses to fertilizer application at the field scale. Furthermore, the economic implications for the plantation of infield variability in yield response to fertilizer arising from variation in soil properties were examined. </p> <p>The perennial nature and particularities in reproductive morphology of oil palm, including an approximately 8-10 year growth period before mature yields are reached, mean that developing site-specific yield response curves to different nutrient application levels in oil palm requires extensive time and resources. The PORIM model, developed by the Malaysian Palm Oil Board (MPOB) across multiple decades of extensive and continuous field testing, is one of the most commonly used methods by which plantations can estimate yield response at different levels of fertilizer application. Traditionally, the PORIM model is run by using site-specific low-resolution vector-layer soil analysis to adjust various parameters in multiple equation systems developed using statistical methods and many decades worth of field tests by the MPOB. In this study, the PORIM model is used as the basis for a methodology to employ a precision approach to fertilizer management in oil palm using high-resolution raster-layer soil property maps and a constrained-optimization model programmed in the General Algebraic Modeling System (GAMS). </p>

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21312号 / 農博第2297号 / 新制||農||1065(附属図書館) / 学位論文||H30||N5146(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 舟川 晋也, 教授 縄田 栄治, 教授 北山 兼弘 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

In dieser Studie wird ein neues Modul “CLM-Palm” für mehrjährige Nutzpflanzen zur Modellierung einer funktionellen Gruppe (plant functional type) für Ölpalmen im Rahmen des Community Land Models (CLM4.5) entwickelt, um die Auswirkungen der Transformation eines tropischen Waldes in eine Ölpalmenplantage auf die Kohlenstoff-, Wasser- und Energieflüsse zwischen Land und Atmosphäre zu quantifizieren. Um die Morphologie der Ölpalme möglichst detailgetreu darzustellen (das heißt, dass ungefähr 40 Phytomere einen mehrschichtigen Kronenraum formen), wird in dem Modul CLM-Palm eine phänologische und  physiologische Parametrisierung auf Skalen unterhalb des Kronraums eingeführt, so dass jedem Phytomer sein eigenes prognostisches Blattwachstum und seine Erntekapazität zugeordnet wird, während Stamm und Wurzeln gemeinsam genutzt werden. Das Modul CLM-Palm wurde ausschließlich für Ölpalmen getestet, ist aber auch für andere Palmarten (z. B. Kokospalmen) interessant.  Im ersten Kapitel dieser Arbeit werden Hintergrund und Motivation dieser Arbeit vorgestellt. In Kapitel 2 wird die Entwicklung des Haupt- bzw. Kernmodells beschrieben,  inklusive Phänologie und Allokationsfunktionen zur Simulation des Wachstums und des Ertrags der Palme PFT, wodurch die Basis zur Modellierung  der biophysikalischen und biogeochemicalischen Kreisläufe innerhalb dieser Monokultur bereitgestellt wird. Die neuen Parameter für die Phänologie und die Allokation wurden sorgfältig mit Feldmessungen des Blattflächenindexes (LAI), des Ertrags und der Nettoprimärproduktion (NPP) verschiedener Ölpalmenplantagen auf Sumatra (Indonesien) kalibriert und validiert. Die Validierung zeigte die Eignung von CLM-Palm zur adäquaten Vorhersage des mittleren Blattwachstums und Ertrags für verschiedene Standorte und repräsentiert in ausreichendem Maß die signifikante Variabilität bezüglich des Stickstoffs und Alters von Standort zu Standort.  In Kapitel 3 wird die weitere Modellentwicklung und die Implementierung eines Norman-Mehrschichtmodells für den Strahlungstransport vorgestellt, das an den  mehrschichtigen Kronenraum der Ölpalme angepasst ist. Dieses Norman-Mehrschichtmodell des Strahlungstransports zeigte im Vergleich zu dem in CLM4.5 implementierten Standardmodell (basierend auf großen Blättern) bei der Simulation der Licht-Photosynthese-Kurve leichte Verbesserungen und hat  lediglich marginale Vorteile gegenüber dem ebenfalls in CLM4.5 implementierten alternativen statistischen Mehrschichtmodell.  Dennoch liefert das Norman-Modell eine detailliertere und realistischere Repräsentation des Belaubungszustands wie etwa dem dynamischen LAI, der Blattwinkelverteilung in verschiedenen Höhen, und ein ausgewogeneres Profil der absorbierten photosynthetisch aktiven Strahlung (PAR). Die Validierung mit Hilfe der Eddy-Kovarianz Flussdaten zeigte die Stärke von CLM-Palm bei der Simulation der Kohlenstoffflüsse, offenbarte aber auch Abweichungen in der simulierten Evapotranspiration (ET), dem sensiblen und dem latenten Wärmefluss (H und LE). Eine Reihe von hydrologischen Messungen im Kronenraum wird in Kapitel 4 beschrieben. Dies beinhaltet eine Adaption des in CLM4.5 eingebauten Standardmodells für Niederschlag, Interzeption und Speicherfunktionen für die speziellen Merkmale eines Ölpalmen-Kronenraums. Die überarbeitete Hydrologie des Kronenraums behob die Probleme bei der Simulation der Wasserflüsse (ET und Transpiration im Kronenraum) und verbesserte die Energieaufteilung zwischen H und LE. Kapitel 5 dokumentiert die Implementierung eines neuen dynamischen Modells für Stickstoff (nitrogen, N) in CLM-Palm zur Verbesserung der Simulation der C- und N-Dynamik, insbesondere mit Bezug auf den N-Düngeeffekte in landwirtschaftlich genutzten Systemen. Das dynamische N-Modell durchbricht die Limitierung des Standardmodells in CLM4.5, mit fixierter C-N-Stöchiometrie und erlaubt die Variation des C:N-Verhältnisses in lebendem Gewebe in Abhängigkeit der N-Verfügbarkeit und dem N-Bedarf der Pflanze.  Eine Reihe von Tests bezüglich der Düngung zeigte beispielhaft die Vorteile des dynamischen N-Modells, wie zum Beispiel die Verbesserung des Netto-Ökosystemaustauschs (net ecosystem exchange, NEE), ein realistischeres C:N-Verhältnis im Blatt, eine verbesserte Repräsentation der Effizienz des Stickstoffeinsatzes (nitrogen-use efficiency, NUE), sowie der Effekte von Düngung auf Wachstum und Ertrag. Abschließend wird in Kapitel 6 eine Anwendungsstudie gezeigt, in der die zentralen Modellentwicklungen aus den vorangegangenen Kapiteln verwendet werden. Eine junge und eine  erntereife Ölpalmenplantage sowie ein Primärregenwald wurden simuliert und verglichen. Sie wiesen klare Unterschiede in den C-Flüssen und in den biophysikalischen Merkmalen (z.B. ET und Oberflächentemperatur) auf. Ölpalmenplantagen können durch Wachstumsentwicklung (im Alter von etwa 4 Jahren)  ebenso hohe und darüber hinausgehende C-Assimilation und Wassernutzungsraten erreichen wie Regenwälder, haben jedoch im Allgemeinen eine höhere Oberflächentemperatur als eine bewaldete Fläche – dies gilt auch für erntereife Plantagen. Eine Simulation des Übergangs, die zwei Rotationsperioden mit Neubepflanzungen alle 25 Jahre umspannt, zeigte dass der Anbau von Ölpalmen auf längeren Zeitskalen lediglich in etwa die Hälfte des ursprünglichen C-Speichers der bewaldeten Fläche vor dem Kahlschlag  rückspeichern kann. Das im Boden gespeicherte C nimmt in einer bewirtschafteten Plantage aufgrund des begrenzten Streurücklaufs langsam und graduell ab. Insgesamt reduziert die Umwandlung eines Regenwaldes in eine Ölpalmenplantage die langfristigen C-Speicher und die Kapazität der Fläche zur C-Sequestrierung und trägt potentiell zur Erwärmung der Landoberfläche bei – trotz des schnellen Wachstums und der hohen C-Assimilationsrate einer stark gedüngten Plantage. Zur Einschätzung der regionalen und globalen Effekte der Ausbreitung der Kultivierung von Ölpalmen auf die Austauschprozesse zwischen Land und Atmosphäre und auf das Klima ist es notwendig eine Upscaling-Studie durchzuführen.

付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 新制・課程博士 / 博士(工学) / 甲第23163号 / 工博第4807号 / 新制||工||1752(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 立川 康人, 教授 田中 茂信, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Rodents often colonise agricultural lands and become pests that cause economic loss and crop damage. Eradicating or regulating pest numbers has economic and environmental costs and has always been of great interest to farmers and nature conservationists. To reduce rodent numbers poison baits are used more often than biological control. However, poisoning has adverse environmental impacts and ignores the underlying biological factors that influence pest abundance. This study examined the interactions of the common rat species of oil palm plantations, namely Rattus rattus diardii, R. argentiventer and R. tiomanicus, with their food resource, habitat structure and introduced predators in an attempt to provide a better understanding and approach for their control. To investigate the interrelationships among rodents, owls and oil palms, rodent trapping was conducted simultaneously with pellet collection and assessment of the breeding of owls over six study plots and seven trapping intervals in one oil palm plantation. Trapping records suggested that relative abundances of rodent species differed in plots with palms of differing ages. There were more R. r. diardii as a proportion of the total captures in older palms (seven years old) while R. argentiventer was the most common rat captured in younger palms (three years old). The abundance of R. tiomanicus remained low throughout trapping sessions for palms of all ages. A numerical response of rats to fruit availability in older palms was demonstrated by a positive and significant correlation between the numbers of fruit bunches present and the total number of rats captured. This relationship was observed in both older and younger palms only for R. argentiventer but not R. r. diardii or R. tiomanicus in either age of palms. This suggests that the competitiveness of R. argentiventer may be higher than that of the other two species providing that there were no factors other than food availability that limit the numbers of other two species. However, the levels of damage to palm fruit were significantly correlated with the relative abundance of R. argentiventer only in younger palms, not in older ones where R. r. diardii were more abundant. The more terrestrial nature of R. argentiventer may have restricted their acquisition of food when the palms became taller. In addition to differences in feeding niche, habitat heterogeneity may also be important in determining the rat species compositions at different ages of palms. Vegetation cover may act as a refuge for rats; the overall occurrence of rats, and especially R. argentiventer, was positively correlated with vegetation cover and height, and even certain vegetation associations. This study supported the continued use of the barn owl Tyto alba javanica for biological control of rodent pests in the palm oil plantations. The numbers of different rat species consumed by owls, as measured by pellet numbers, were proportional to prey captures with R. r. diardii dominating the prey items. Weights and sexes of rats, based upon sizes of bones recovered from owl pellets, indicated that the birds did not preferentially prey on any size or sex classes of rats. Although there was no differential predation by the owls, a functional, and possibly a numerical, response of the birds to changes in rat numbers was demonstrated. A functional response of barn owls to prey abundance was evidenced by a significant positive relationship between the relative abundance of rats captured and numbers of pellets collected. Some form of numerical response of barn owls was suggested by higher breeding records when rat abundances were significantly higher. Since both functional and numerical responses are important determinants of whether predators are likely to be able to regulate prey numbers, the role of barn owls as a practical biological control agent in oil palm plantations was supported. This study suggested that the regulation of rodent pests in oil palm plantations should not be limited to chemical measures but can be complemented by other biological factors including interspecific interactions, manipulation of the availability and density of food and habitat structure, in addition to predation by barn owls. The findings suggested that an integrated approach to rodent control, considering all biological factors that influence rat numbers, should be properly applied if an environmentally friendly and possibly cost effective approach is to be applied for the palm oil industry.

Native to the world’s third-largest tropical rainforest, the indigenous people of West Papua, known as Papuan, have experienced substantial changes to their ecosystem over the last several decades, primarily to their water resources. As surface water has been a primary asset for drinking water consumption and their livelihoods for generations, the increase in pollution from expanding oil palm plantations impacts many lives. Receiving limited attention, disentangling this water injustice from power relations as a byproduct of the state-backed development, corporate-driven expansions, and consumer demand become pivotal to advocating for the indigenous community and their livelihoods. Therefore, this study explores integrating physical evidence of agricultural runoff from oil palm plantations and indigenous perceptions using hydro-social territories in a remote area in West Papua, Indonesia. Due to the lack of long-term investigations of the impact of water contamination in West Papua, a hydrological model will be used to assess the nature of the oil palm impact within the watershed. As deterioration in water quality is expected due to landscape changes, the indigenous perception of hydrological changes is crucial to determine how significant the impact is on local livelihoods. Semi-structured interviews will be used to study the perception of indigenous communities on water resources and threats of oil palm to their livelihood. The synthesis of those results will later be concluded using the hydro-social approach, involving a multi-scale analysis that includes Indonesian state and corporate actors through literature reviews from various sources (e.g., official documentation, corporate reports, and journals). This research will develop strategies to protect indigenous communities not yet impacted by large-scale changes in the watershed resulting from palm oil plantations.

Orientador: Bernadete Aparecida Caprioglio de Castro / Resumen: La presente investigación tuvo como objetivo analizar las transformaciones en las actividades productivas de mujeres campesinas por la expansión del cultivo de palma de aceite en sus territorios. Dicha expansión es debida a las dinámicas globales de la territorialización del capital en las áreas rurales mediante la compra y acaparamientos de tierras por parte de inversores privados, con el fin de instalar grandes plantaciones de monocultivos, proyectos de infraestructura y/o exploraciones de minerales, para lo cual han contado con el apoyo de los gobiernos nacionales, mediante la reorientación de las políticas públicas agrarias que les permitan la intervención en los territorios locales. Los países latinoamericanos no han estado exentos de éstas dinámicas globales, entre ellos Colombia, el cual ha incrementado las áreas de cultivo de la palma de aceite con fines exportables durante el presente siglo, generando transformaciones en los medios de vidas de las comunidades rurales, campesinas y étnicas, por la ocupación material y simbólica de sus territorios, por la apropiación de sus recursos, entre ellos la tierra y el agua, de los cuales las comunidades derivan el sustento. Estas transformaciones se presentan de manera diferenciada en las mujeres campesinas, por las relaciones patriarcales-capitalistas y discriminatorias en las que viven, en donde su voz y reconocimiento tanto en lo productivo como reproductivo es invisibilizado, al igual que sus derechos en la propiedad de lo... (Resumen completo clicar acceso eletrônico abajo) / Resumo: A presente pesquisa teve como objetivo avaliar as mudanças nas atividades produtivas de mulheres rurais Afro-colombianas devido à expansão em seus territórios do cultivo da palma de óleo. Essa expansão é o resultado da dinâmica global de territorialização do capital nas zonas rurais por meio da compra e acumulação de terras por investidores privados, a fim de instalar grandes monoculturas, projetos de infraestrutura e/ou exploração de minerais, para o qual têm recebido o apoio dos governos nacionais com a reorientação de políticas agrícolas que lhes permitem a intervenção em territórios locais. Os países da América Latina, incluindo a Colômbia, não são isentos dessa dinâmica global. Este país tem aumentado as áreas de cultivo da palma de óleo para fins de exportação durante as últimas duas décadas. Isto levou a uma transformação nos meios de vida das comunidades rurais e étnicas, devido à ocupação física e simbólica de seus territórios, à apropriação dos seus recursos, incluindo terra e água, dos quais essas comunidades obtém seu sustento. Essas transformações são vivenciadas de forma diferente nas mulheres camponesas, devido às relações patriarcais-capitalistas e discriminatórias em que vivem, onde a sua voz e reconhecimento tanto no produtivo quanto no reprodutivo é invisível, da mesma maneira que os seus direitos sobre a propriedade dos ativos produtivos. Situações que as levam a uma maior condição de vulnerabilidade, empobrecimento e dependência. Este estudo foi realizado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to assess changes in the productive activities of Afro Colombian rural women due to the expansion of oil palm plantation in their territories. This expansion is a result of global dynamics of territorialization of capital in rural areas through the purchase and ownership of lands by private investors in order to install large monocrop plantations, infrastructure projects and/or mineral exploration. For which investors have been supported by national governments through the readjustment of agricultural policies that allow them to interfere in local territories. Latin American countries, including Colombia, have not been exempt from global dynamics. This country has increased areas of palm oil plantation to serve exportation purposes during the last two decades, which has led to transformation in the means of living of rural and ethnic communities, due to the physical and symbolic occupation of their territories and the appropriation of their resources, including land and water, from which communities derive their sustenance. These transformations are presented differently on rural women, because of the patriarchal-capitalist and discriminatory societies in which they live, where their voice and recognition to both productive and reproductive aspects are made invisible, as well as their rights to the ownership of the productive assets. Situations that leave them in a more vulnerable condition of impoverishment and dependence. We carried out a qualitative study ... (Complete abstract click electronic access below) / Mestre

Submitted by MARGARITA INES RESTREPO MENDEZ null (mirestrepo10@gmail.com) on 2017-07-07T00:52:01Z No. of bitstreams: 1 Dissertação vfinal2017.pdf: 4896894 bytes, checksum: 23260c7c562f17485d66b4630c7dd377 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-07-13T16:33:05Z (GMT) No. of bitstreams: 1 mendez_mir_me_ippri.pdf: 4896894 bytes, checksum: 23260c7c562f17485d66b4630c7dd377 (MD5) / Made available in DSpace on 2017-07-13T16:33:05Z (GMT). No. of bitstreams: 1 mendez_mir_me_ippri.pdf: 4896894 bytes, checksum: 23260c7c562f17485d66b4630c7dd377 (MD5) Previous issue date: 2017-05-18 / A presente pesquisa teve como objetivo avaliar as mudanças nas atividades produtivas de mulheres rurais Afro-colombianas devido à expansão em seus territórios do cultivo da palma de óleo. Essa expansão é o resultado da dinâmica global de territorialização do capital nas zonas rurais por meio da compra e acumulação de terras por investidores privados, a fim de instalar grandes monoculturas, projetos de infraestrutura e/ou exploração de minerais, para o qual têm recebido o apoio dos governos nacionais com a reorientação de políticas agrícolas que lhes permitem a intervenção em territórios locais. Os países da América Latina, incluindo a Colômbia, não são isentos dessa dinâmica global. Este país tem aumentado as áreas de cultivo da palma de óleo para fins de exportação durante as últimas duas décadas. Isto levou a uma transformação nos meios de vida das comunidades rurais e étnicas, devido à ocupação física e simbólica de seus territórios, à apropriação dos seus recursos, incluindo terra e água, dos quais essas comunidades obtém seu sustento. Essas transformações são vivenciadas de forma diferente nas mulheres camponesas, devido às relações patriarcais-capitalistas e discriminatórias em que vivem, onde a sua voz e reconhecimento tanto no produtivo quanto no reprodutivo é invisível, da mesma maneira que os seus direitos sobre a propriedade dos ativos produtivos. Situações que as levam a uma maior condição de vulnerabilidade, empobrecimento e dependência. Este estudo foi realizado no município de Maríalabaja, cidade localizada no norte da Colômbia. Este município era produtor de uma grande quantidade e variedade de alimentos antes de 1998, quando se começou a instalar o cultivo da palma de óleo. Além disso, a maioria da sua população autodeclara-se camponesa e tem sido afetada pelo conflito armado interno colombiano. Foi usada uma metodologia qualitativa com o objetivo de descrever as atividades realizadas por mulheres pertencentes a organizações de agricultores, antes e após a instalação cultivo da palma de óleo, analisando as transformações vivenciadas por elas, as formas de resistência e os desafios que enfrentam para permanecer no território. / This study aimed to assess changes in the productive activities of Afro Colombian rural women due to the expansion of oil palm plantation in their territories. This expansion is a result of global dynamics of territorialization of capital in rural areas through the purchase and ownership of lands by private investors in order to install large monocrop plantations, infrastructure projects and/or mineral exploration. For which investors have been supported by national governments through the readjustment of agricultural policies that allow them to interfere in local territories. Latin American countries, including Colombia, have not been exempt from global dynamics. This country has increased areas of palm oil plantation to serve exportation purposes during the last two decades, which has led to transformation in the means of living of rural and ethnic communities, due to the physical and symbolic occupation of their territories and the appropriation of their resources, including land and water, from which communities derive their sustenance. These transformations are presented differently on rural women, because of the patriarchal-capitalist and discriminatory societies in which they live, where their voice and recognition to both productive and reproductive aspects are made invisible, as well as their rights to the ownership of the productive assets. Situations that leave them in a more vulnerable condition of impoverishment and dependence. We carried out a qualitative study in the municipality Maríalabaja which is located in Northern Colombia. This town used to produce large quantity and variety of food before 1998 when the setting-up of oil palm plantation started. In addition, the majority of its population considers themselves farmers and has suffered the Colombian internal armed conflict. We aimed to describe the activities carried out by women belonging to farmers' organizations before and after the setting-up of oil palm plantation, and to assess transformations experienced by them in their means of living, ways of resistance and challenges they currently face to remain in the territory. / La presente investigación tuvo como objetivo analizar las transformaciones en las actividades productivas de mujeres campesinas por la expansión del cultivo de palma de aceite en sus territorios. Dicha expansión es debida a las dinámicas globales de la territorialización del capital en las áreas rurales mediante la compra y acaparamientos de tierras por parte de inversores privados, con el fin de instalar grandes plantaciones de monocultivos, proyectos de infraestructura y/o exploraciones de minerales, para lo cual han contado con el apoyo de los gobiernos nacionales, mediante la reorientación de las políticas públicas agrarias que les permitan la intervención en los territorios locales. Los países latinoamericanos no han estado exentos de éstas dinámicas globales, entre ellos Colombia, el cual ha incrementado las áreas de cultivo de la palma de aceite con fines exportables durante el presente siglo, generando transformaciones en los medios de vidas de las comunidades rurales, campesinas y étnicas, por la ocupación material y simbólica de sus territorios, por la apropiación de sus recursos, entre ellos la tierra y el agua, de los cuales las comunidades derivan el sustento. Estas transformaciones se presentan de manera diferenciada en las mujeres campesinas, por las relaciones patriarcales-capitalistas y discriminatorias en las que viven, en donde su voz y reconocimiento tanto en lo productivo como reproductivo es invisibilizado, al igual que sus derechos en la propiedad de los activos productivos. Situaciones que llevan a empobrecerlas, siendo menos autónomas y más dependientes y vulnerables. Para la presente investigación se recurre a la metodología cualitativa, tomando como estudio de caso el municipio de Maríalabaja, ubicado al norte de Colombia, el cual era productor de gran cantidad y variedad de alimentos antes de 1998 cuando comenzó la instalación del cultivo de palma de aceite, y además caracterizado porque la mayoría de su población ha sufrido el conflicto armado interno colombiano. La investigación pretendió conocer las actividades productivas desarrolladas por las mujeres que pertenecen a organizaciones campesinas antes y después de la instalación del cultivo, analizando las transformaciones vivenciadas por ellas, las formas de resistencia y los desafíos que enfrentan para permanecer en el territorio.

La lutte contre les rongeurs est souvent un enjeu majeur dans les agroécosystèmes. Nous avons conduit une étude comparative dans des plantations de palmiers à huile dans les provinces de Riau et de Bangka en Indonésie. Dans les deux zones, des chouettes ont été introduites pour la lutte contre les rats ; toutefois, à Riau les rats sont maintenus à des niveaux de population acceptables sans recours au raticide, tandis qu’à Bangka les dégâts des rats sont très importants et l’usage de raticide intensif. Nous avons comparé ce deux systèmes en terme d’abondance et/ou de régime alimentaire de deux prédateurs, chouettes et petits carnivores. D’après nos résultats, les petits carnivores sont beaucoup plus abondants dans les plantations à Riau qu’à Bangka, et le chat léopard (Prionailurus bengalensis) est absent à Bangka tandis que cette espèce domine à Riau. Nos résultats suggèrent également que la prédation sur les rats par les chouettes et les petits carnivores serait moindre à Bangka qu’à Riau. D’une manière générale, cette étude confirme l’hypothèse selon laquelle les petits carnivores, notamment les chats léopard, joueraient un rôle important dans la lutte contre les rats en palmeraies. Par ailleurs, nous avons analysé la distribution spatiale des petits carnivores en plantation. Nos résultats suggèrent que, bien que l’habitat palmeraie soit largement utilisé la nuit par certains petits carnivores comme le chat leopard, qui y trouve une abondante ressource alimentaire, la plupart des espèces sont dépendantes de la forêt. Les gestionnaires des palmeraies devraient adapter leurs pratiques, afin de favoriser les petits carnivores dans une perspective de lutte contre les rats. / Rodent pest control is often a major issue in agroecosystems. We conducted a 3-year comparative study (2010-2012) in oil palm plantations in Riau and Bangka provinces, in Indonesia: in both areas barn owls have been introduced for rat control, and were at least as abundant in Bangka plantations than in Riau, but in Riau rat populations have been maintained at an acceptable level without the use of rodenticide, whereas in Bangka intensive rodenticide applications did not prevent high levels of rat damage. We compared these two contrasting systems in terms of predator community (barn owls and small carnivores) abundance and/or diet. We found that small carnivores were much more abundant in Riau plantations than in Bangka, and that the leopard cat (Prionailurus bengalensis) was the dominant species in Riau while absent from Bangka. Our results on diet suggested that rat prey intake from barn owls and from the small carnivore community would be less in Bangka plantations than in Riau. Broadly, our results suggest that small carnivores, notably the leopard cat, play an important role in rodent control. In addition, we investigated spatial distribution of small carnivores within the oil palm habitat. Our results support the hypothesis that, although the oil palm may be habitable for some small carnivore species such as the leopard cat, where they supposedly forage at night, most species still need forest for their survival in oil palm landscapes. Oil palm plantations managers should adapt agricultural practices and land-use to enhance small carnivores, with the view to improve rodent control.