The opportunistic feeding and reproduction strategies of the annual fish Cynopoecilus melanotaenia (Cyprinodontiformes: Rivulidae) inhabiting ephemeral habitats on southern Brazil

A maioria dos peixes da família Rivulidae são popularmente conhecidos como anuais por completarem todo seu ciclo biológico em pequenos corpos de água temporários que secam obrigatoriamente em determinados períodos do ano causando a morte dos indivíduos adultos. Possuem características biológicas peculiares como pequeno porte, maturação sexual precoce, reprodução contínua, um elaborado padrão de corte e uma grande capacidade reprodutiva entre os peixes. Os rivulídeos se encontram amplamente distribuídos nas Américas do Norte, Central e Sul. Este trabalho analisou a dieta e a biologia reprodutiva de Cynopoecilus melanotaenia. Foram coletados 263 exemplares e a análise de 233 conteúdos gastrointestinais revelou uma dieta invertívora composta principalmente por microcrustáceos (Cladocera, Amphipoda e Ostracoda) e insetos imaturos (Chaoboridae, Culicidae, Syrphidae, mas principalmente larvas de Chironomidae). Foi registrada a lepidofagia na dieta dos machos. A fecundidade foi estimada pela análise de 59 pares de ovários maduros e variou entre 2 a 157 ovócitos (média, 19 ± 26[DP]). A espécie apresentou desova parcelada, uma estratégia para aumentar a chance de sobrevivência a depleções prolongadas. Este trabalho apresenta a primeira investigação sobre a biologia reprodutiva de C. melanotaenia. Os resultados encontrados sugerem a estratégia reprodutiva oportunista de C. melanotaenia e fornecem novas informações biológicas que podem contribuir para pesquisas de conservação e manutenção da espécie em seu ambiente natural.

Murtuva säätyvalta, kestävä eliitti : Senaattori Lennart Gripenbergin sukupiiri ja sääty-yhteiskunnan muodonmuutos

This study examines the transformation of the society of estates in the Finnish Grand Duchy through the case study of Senator Lennart Gripenberg and his family circle. While national borders and state structures changed, the connections between old ruling elite families remained intact as invisible family networks, ownership relations, economic collaboration and power of military families. These were the cornerstones of trust, which helped to strengthen positions gained in society. Also, these connections often had a central if unperceivable impact on social development and modernization. Broadly speaking, the intergenerational social reproduction made it possible for this network of connections to remain in power and, as an imperceptible factor, also influenced short-term developments in the long run. Decisions which in the short term appeared unproductive, would in the long run produce cumulative immaterial and material capital across generations as long-term investments. Social mobility, then, is a process which clearly takes several generations to become manifest. The study explores long-term strategies of reproducing and transferring the capital accumulated in multinational elite networks. Also, what was the relationship of these strategies to social change? For the representatives of the military estate the nobility and for those men of the highest estates who had benefited from military training, this very education of a technical-military nature was the key to steering, controlling and dealing with the challenges following the industrial breakthrough. The disintegration of the society of estates and the rising educational standards also increased the influence of those professionals previously excluded, which served to intensify competition for positions of power. The family connections highlighted in this study overlapped in many ways, working side by side and in tandem to manage the economic and political life in Finland, Russia and Sweden. The analysis of these ties has opened up a new angle to economic co-operation, for example, as seen in the position of such family networks not only in Finnish, but also Swedish and Russian corporations and in the long historical background of the collaboration. This also highlights in a new way the role of women in transferring the cumulative social capital and as silent business partners. The marriage strategies evident in business life clearly had an impact on the economic life. The collaborative networks which transcended generations, national boundaries and structures also uncover, as far as the elites are concerned, serious problems in comparative studies conducted from purely national premises. As the same influential families and persons in effect held several leading positions in society, the line would blur between public and invisible uses of power. The power networks thus aimed to build monopolies to secure their key positions at the helm. This study therefore examines the roles of Lennart Gripenberg senator, business executive, superintendent of the Department of Industry, factory inspector, and founding member of industrial interest groups as part of the reproduction strategies of the elite. The family and other networks of the powerful leaders of society, distinguished by social, economic and cultural capital, provided a solid backdrop for the so-called old elites in their quest for strategies to reproducing power in a changing world. Crucially, it was easier for the elites to gain expertise to steer the modernization process and thereby secure for the next generation a leading position in society, something that they traditionally, too, had had the greatest interest in.

Relações de trabalho no espaço rural friburguense: pluriatividade e complexificação das relações sociais de produção

Esse estudo tem como objetivo analisar o fenômeno da pluriatividade nos pequenos estabelecimentos familiares do espaço rural do município de Nova Friburgo, localizado na região Serrana do estado do Rio de Janeiro. Retomando a ênfase (presente em trabalho anterior) nos efeitos sociais promovidos pela inserção do espaço rural municipal em uma lógica de mercado, e, levando em consideração as cautelas que devem ser tomadas, no âmbito nacional, na utilização de tal noção, a nossa intenção foi a de questionarmos as valorações que vêm sendo atribuídas a esse fenômeno (de possibilidade de diversificação de emprego e renda; melhoria das condições de vida das populações rurais; e, até mesmo, do estabelecimento de um espaço rural dotado de múltiplas funções), a partir de uma realidade como a friburguense. Esta se, por um lado, é marcada pela significativa expressão espacial dos pequenos estabelecimentos familiares e por um quadro econômico, relativamente, diversificado, por outro lado, também, sofre os efeitos da implementação de um modelo de modernização da agricultura, extremamente excludente e desigual, e, em menor escala, do avanço de um intenso processo de urbanização. Analisado como estratégia de sobrevivência e reprodução no recorte espacial mencionado, os desdobramentos do fenômeno da pluriatividade identificados no mesmo, de certo, complexificam a realidade estudada, ficando a dialética entre relações capitalistas e não-capitalistas, balizada, grosso modo, pela permanência da agricultura com ênfase no trabalho familiar, de um lado, e pela expansão de uma lógica urbano-industrial que, além (e para além) de relações setoriais, também, envolve a inserção de membros das famílias dos pequenos produtores em outras atividades, não-agrícolas, de outro. Para que fosse atingido, portanto, o objetivo proposto, a operacionalização adotada consistiu tanto no levantamento bibliográfico acerca da temática escolhida quanto na realização de vários trabalhos de campo, direcionados a pequenos estabelecimentos familiares de algumas localidades dos vários distritos do município, assim como a órgãos públicos, ligados à produção agrícola, ao turismo e às indústrias de confecções de moda íntima.

科尔沁沙地西部草甸植物繁殖对策

本文以科尔沁沙地西部草甸植物为研究对象，从草甸植物的繁殖体形态学、种子萌发特征、花期和果期、结种量和土壤种子库等方面分析了草甸植物的繁殖对策，探讨了草甸植物的繁殖对策与放牧、割草等干扰的关系。研究结果表明：（1）在科尔沁沙地西部草甸植被中，开花早，结果早的植物能够更好的适应自由放牧和秋季割草；（2）科尔沁沙地西部草甸割草草地极小粒种子的植物密度比大粒种子和小粒种子的植物密度小；在放牧草地小粒种子植物密度远远大于大粒种子和极小粒种子的植物密度；（3）在实验室条件下，64种草甸植物种子萌发能力的差异明显；小粒种子、长形或圆锥形种子、具芒和冠毛的繁殖体一般具有高的萌发能力；放牧草地一般由高萌发能力的一年生植物和低萌发能力的多年生植物组成；割草草地一般由低萌发能力的一年生植物和高萌发能力的多年生植物组成；（4）自由放牧草地土壤种子库密度小于秋季割草地，放牧草地种子库密度与地上植物出现频率和多度相关不显著，而割草地种子库物种与地上植物多度具有显著的相关性（r＝0.76，P＜0.01）；〔5）在科尔沁沙地西部草甸植被中，20种草甸植物具有持久种子库，其中豆科植物和一年生植物占据较大的比例。

青藏高原东缘川西云杉林皆伐后灌木生长、繁殖与更新的研究

植物群落及其环境在干扰后的演替格局和过程的研究，是群落和生态系统动态研究的一个热点。选取青藏高原东缘山原区川西云杉林皆伐后，从草地过渡到灌丛的关键阶段的4 个皆伐迹地（恢复时间为8 a、10 a、16 a 和21 a），研究皆伐及自然恢复过程对林下典型灌木银露梅（Potentilla glabra）和唐古特忍冬（Lonicera tangutica）的生长与繁殖能力的影响以及灌木植物在迹地上的更新情况，分析灌木在不同生境中的适应对策和适应能力的差异,为揭示青藏高原东缘山原区迹地植被从草甸到灌丛演替的过程和特点及促进迹地演替与植被恢复进程提供理论依据和技术支撑。研究主要结论如下：1）皆伐后银露梅生长和繁殖能力显著提高，但对唐古特忍冬的影响不明显。皆伐后银露梅丛基径、高度和各部分生物量都显著增加（P < 0.05），但唐古特忍冬只有叶生物量和地下生物量增加，总生物量和其余构件生物量无显著变化。皆伐后，银露梅的结实数量、结实株数、不结实株数和结实株/不结实株比例显著增加（P < 0.05）。自然恢复过程中，银露梅和唐古特忍冬生长能力以及银露梅的结实量都表现出降低的趋势。随着迹地自然恢复时间的增加，银露梅和唐古特忍冬的基径、高度、丛叶片数和各部分生物量有减少的趋势。银露梅的结实株数增加, 但结实数量减少。2）皆伐对银露梅和唐古特忍冬生物量分配模式影响不一致。原始林和迹地中（除CT85）银露梅的生物量大小关系皆为：地下>茎>侧枝>叶。唐古特忍冬在原始林中的生物量大小关系为：茎＞地下部分＞侧枝＞叶,而皆伐后生物量的分配情况改变，生物量大小关系变为：地下部分＞茎＞侧枝＞叶。随着自然恢复时间的增加，银露梅减少了地下生物量的分配，而唐古特忍冬增加了地下生物量的分配。3）皆伐和恢复时间的增加改变了迹地物种组成，促使阳性乔、灌木在迹地上定居。4 个迹地上共出现了灌木15 种，乔木3 种，没有出现天然云杉和冷杉幼苗。随着恢复时间的增加，迹地上的灌木物种由原始林下的耐阴物种逐步发展为以针刺悬钩子（Rubus pungens）为主的阳性灌木。4）影响灌木幼苗密度和幼树密度的因子不一致。灌木幼苗密度与灌木层盖度显著负相关，与苔藓层盖度显著正相关。幼树密度与草本层盖度正相关，与苔藓层盖度、灌木层盖度和高度负相关。5）研究发现在青藏高原东缘山原区皆伐15～20 a 后，迹地仍以草本植物为主，推测皆伐后至少20 a 以上迹地才可能向灌丛阶段过渡，比高山峡谷地区的演替进程至少推迟了20 a。银露梅和唐古特忍冬在皆伐后自然恢复过程中表现出不同的生长与繁殖策略是由两个物种的生物学特性的差异引起的。银露梅比唐古特忍冬更适应迹地退化环境。促进青藏高原东缘山原林区迹地森林恢复一方面是尽量减少人为活动的破坏，另一方面，可以通过在迹地中播种适当的乡土乔、灌木种子（如白桦、银露梅）等人工措施，以加快演替进程。The succession pattern and process of plant community and their environments is a hot spotin community and ecosystem dynamic study. Four clearcuts were chosen in Rangtang(recovery time of 8 a、10 a、16 a and 21 a), which represented the key stage of thecommunity evolved from grass stage to shrub stage in the eastern margin of theQinghai-Tibetan Plateau. The growth and reproduction of the Potentilla glabra andLonicera tangutica and the natural regeneration of shrub plants in the primary Piceabalfouriana forest and 4 clearcuts were studied to explore how clear cutting andnatural recovery process affected the understory shrub species during the 21 years inthe eastern margin of the Qinghai-Tibetan Plateau. The main results were below.1) The growth and reproduction of P. glabra significantly increased after forestclear cutting.. But it was not so significant as to the L. tangutica. The organismbiomass and total biomass of P. glabra were increased obviously after clear cutting（P< 0.05）. But only leaves and underground biomass of L. tangutica increasedsignificantly after clear cutting（P < 0.05）. The number of fruit and growth of P. glabraincreased significantly after clear cutting too（P < 0.05）. The ramet height, basaldiameter , organism biomass and friut number of P. glabra and L. tangutica reducedas the increase of recovery time.2) The biomass allocation patterns varied between P. glabra and L. tangutica inthe primary forest and clearcuts. The biomass allocation of P. glabra both in primary forest and clearcuts was followed as: underground part > stem > branch > leaves.However, the biomass allocation of L. tangutica had changed after the clear cutting.The biomass allocation of L. tangutica in the primary forest was followed as: stem >underground part > branch > leaves and it was underground part > stem > branch >leave in clearcuts. The biomass allocation of P. glabra and L. tangutica varied amongclearcuts. Aboveground biomass was increased while underground biomass decreasedfor P. glabra with the increase of recovery period. However, the L. tangutica showedthe reverse changing pattern.3) Clear cutting and recovery time had changed the species composition of theclearcuts. There were 15.shruby species and 3 tree species in the four clearcuts. Nospruce and fir seedlings were found. In the early stage after clear cutting, there wereonly understory shrub species from the primary Picea balfouriana forest. The sunnyspecies, especieally Rubus pungens invaded intensly as the increase of recovery time.4) There was a significant negative relationship between density of seedlingswith shrub layer coverage and positive correlation with moss coverage. The saplingshad significantly positive correlation with herb layer coverage and negativecorrelation with moss coverage, shrub layer coverage and height.5）Comparing to studies in Miyalou, a nearby high mountain and canyon area,the secondary sucession in this subalpine plateau areas lagged at least 20 years.P. glabra and L. tangutica showed different growth and reproduction strategies toclear cutting and natural recovery , which may associated with the difference of theirbiological characters. P. glabra was more adaptive to the clear cutting than the L.tangutica. Two suggestions were probably recommended to promote the recoveryprogress in the subalpine plateau areas based on the results of this study. Limitanthropogenic disturbance, and meanwhile sow native tree and shrub seeds inclearcuts.

DISCOVERY 2010: Spatial and temporal variability in a dynamic polar ecosystem

The Scotia Sea has been a focus of biological- and physical oceanographic study since the Discovery expeditions in the early 1900s. It is a physically energetic region with some of the highest levels of productivity in the Southern Ocean. It is also a region within which there have been greater than average levels of change in upper water column temperature. We describe the results of three cruises transecting the central Scotia Sea from south to north in consecutive years and covering spring, summer and autumn periods. We also report on some community level syntheses using both current-day and historical data from this region. A wide range of parameters were measured during the field campaigns, covering the physical oceanography of the region, air–sea CO2 fluxes, macro- and micronutrient concentrations, the composition and biomass of the nano-, micro- and mesoplankton communities, and the distribution and biomass of Antarctic krill and mesopelagic fish. Process studies examined the effect of iron-stress on the physiology of primary producers, reproduction and egestion in Antarctic krill and the transfer of stable isotopes between trophic layers, from primary consumers up to birds and seals. Community level syntheses included an examination of the biomass-spectra, food-web modelling, spatial analysis of multiple trophic layers and historical species distributions. The spatial analyses in particular identified two distinct community types: a northern warmer water community and a southern cold community, their boundary being broadly consistent with the position of the Southern Antarctic Circumpolar Current Front (SACCF). Temperature and ice cover appeared to be the dominant, over-riding factors in driving this pattern. Extensive phytoplankton blooms were a major feature of the surveys, and were persistent in areas such as South Georgia. In situ and bioassay measurements emphasised the important role of iron inputs as facilitators of these blooms. Based on seasonal DIC deficits, the South Georgia bloom was found to contain the strongest seasonal carbon uptake in the ice-free zone of the Southern Ocean. The surveys also encountered low-production, iron-limited regions, a situation more typical of the wider Southern Ocean. The response of primary and secondary consumers to spatial and temporal heterogeneity in production was complex. Many of the life-cycles of small pelagic organisms showed a close coupling to the seasonal cycle of food availability. For instance, Antarctic krill showed a dependence on early, non-ice-associated blooms to facilitate early reproduction. Strategies to buffer against environmental variability were also examined, such as the prevalence of multiyear life-cycles and variability in energy storage levels. Such traits were seen to influence the way in which Scotia Sea communities were structured, with biomass levels in the larger size classes being higher than in other ocean regions. Seasonal development also altered trophic function, with the trophic level of higher predators increasing through the course of the year as additional predator-prey interactions emerged in the lower trophic levels. Finally, our studies re-emphasised the role that the simple phytoplankton-krill-higher predator food chain plays in this Southern Ocean region, particularly south of the SACCF. To the north, alternative food chains, such as those involving copepods, macrozooplankton and mesopelagic fish, were increasingly important. Continued ocean warming in this region is likely to increase the prevalence of such alternative such food chains with Antarctic krill predicted to move southwards.

Analysis of the calving pattern of herds in small-scale dairy systems in central Mexico

This study sets out to find the best calving pattern for small-scale dairy systems in Michoacan State, central Mexico. Two models were built. First, a linear programming model was constructed to optimize calving pattern and herd structure according to metabolizable energy availability. Second, a Markov chain model was built to investigate three reproductive scenarios (good, average and poor) in order to suggest factors that maintain the calving pattern given by the linear programming model. Though it was not possible to maintain the optimal linear programming pattern, the Markov chain model suggested adopting different reproduction strategies according to period of the year that the cow is expected to calve. Comparing different scenarios, the Markov model indicated the effect of calving interval on calving pattern and herd structure.

A Dinâmica agrária do município de Ortigueira(PR) e a reprodução social dos produtores familiares: uma análise das comunidades rurais de Pinhalzinho e Vila Rica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biologia alimentar e reprodutiva na comunidade de peixes do rio Passa Cinco (SP)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mártires de abril: o MST semeando a utopia camponesa

A descrição do Assentamento Mártires de Abril e a análise dos processos de construção das práticas e do discurso sobre sua organização e gestão são o objeto deste trabalho. Desse modo é que se definiu como temática o Estudo das Formas de Organização de Assentamento do MST com a perspectiva de pensar os processos sociais que se foram construindo nos assentamentos de Reforma Agrária do MST no Pará, e a sua complexidade, a partir da experiência do Assentamento Mártires de Abril que apresenta peculiaridades. A forma de organização da produção é uma tentativa de se implantar o projeto de organização de assentamento do MST, que, neste trabalho, foram assim denominados: Grupo Coletivo ou de Produção no Sistema de Cooperação; Semi-coletivo ou Produção Familiar Integrada e Individual ou Produção Familiar Não Integrada. Nesta perspectiva, definiu-se como objetivos do trabalho: compreender os limites e as possibilidades de implementação das formas de organização de assentamento do MST, associando coletivismo e gestão familiar, a partir da experiência do Assentamento Mártires de Abril; identificar os limites e as possibilidades das formas de organização da produção coletiva numa perspectiva de construção da proposta de assentamento; identificar as representações sociais no processo de construção da organização social, econômica e política do assentamento. Foi possível identificar que no Assentamento Mártires de Abril predomina a perspectiva de uma forma de organização da produção coletiva com possibilidade de se desenvolver a semi-coletiva e a individual; existência de diferenciação no nível político-ideológico de cada pessoa assentada, resultando na distinção dos estágios de desenvolvimento dos núcleos de base, o que vai determinar a forma de organização de cada núcleo e as estratégias de reprodução e que o contexto que o Assentamento Mártires de Abril apresenta é de estágio em desenvolvimento, com expressão de conflitos ainda evidentes, face ao processo de definição de uma forma própria de organização de assentamento. Entretanto, existe uma tendência, em médio prazo, à configuração de um projeto definido como uma nova alternativa de assentamento com elementos culturais da velha forma de produção, mesclada à uma nova proposta baseada na exploração semi-coletiva e culturas diversificadas.

A reprodução sócio-econômica e produtiva do campesinato no Sudeste paraense: o Assentamento Palmares II, Parauapebas/PA

O Sudeste Paraense foi palco de um dos maiores e mais incisivos processos de ocupação e colonização da região amazônica em sua totalidade. O elevado contingente migrante camponês ao longo de todo século XX, em especial, nas décadas dos anos de 1970, 1980 e 1990, concorreu diretamente com outras estratégias postas e pensadas para a colonização da região, como a agropecuária de grande porte e extensiva, mineração e projetos de geração de energia. Diante de uma complexidade ímpar no agrário regional, esse cenário é marcado até a atualidade por elevada conflitividade, posicionando claramente a região no debate acadêmico como sendo uma fronteira. A partir de meados dos anos 1990, os conflitos e disputas ganham novos contornos com a criação de Projetos de Assentamentos e a implementação de uma série de políticas voltadas ao atendimento da agricultura familiar, o que possibilita de certa forma pensar em novos tipos de conflitos e possibilidades de reprodução social e econômica dos camponeses assentados. O presente trabalho, dentro desse novo contexto, trata especificamente das possibilidades atuais de reprodução social e econômica do campesinato no assentamento Palmares II, município de Parauapebas/PA, buscando compreender os possíveis fatores que vem permitindo ou não a ruptura com a tese do ciclo e fronteira e em contraposição permitindo certa estabilização aos camponeses assentados. Para além de evidenciar e comprovar a existência de novas trajetórias dos sistemas de produção postas em prática pelos agricultores do assentamento em questão, o trabalho pretende indicar quais fatores econômicos, políticos, sociais têm sido importantes para a continuidade e possibilidade das estratégias de reprodução camponesa.

Filogenia e taxonomia dos veados cinza (Mazama gouazoubira e M. nemorivaga)

Pós-graduação em Genética e Melhoramento Animal - FCAV

Assemblages and isotopic signals of modern ostracodes and host waters from Patagonia, Argentine

Ostracode species assemblages and stable oxygen and carbon isotope ratios of living and recent ostracodes, together with delta18O and delta13C_DIC values of host water samples, provide a first data set that characterizes a wide range of modern aquatic environments in the Laguna Cari-Laufquen (41°S, 68 - 69°W) and the Lago Cardiel area (48 - 49°S, 70 - 71°W) in Patagonia, Argentina. This data set will ultimately be used to interpret and calibrate data acquired from lake sediment cores with the goal of reconstructing past climate. Species assemblages and isotope values can be assigned to three groups; (1) springs, seeps and streams, (2) permanent ponds and lakes, and (3) ephemeral ponds and lakes. Springs, seeps and streams are characterized by Darwinula sp., Heterocypris incongruens, Eucypris fontana, Amphicypris nobilis and Ilyocypris ramirezi. Ostracode and water isotope values range between -13 and -5 per mil for oxygen, and between -15 and -3 per mil for carbon. They are the most negative of the entire sample set, reflecting ground water input with little or no evaporative enrichment. Limnocythere patagonica, Eucypris labyrinthica, Limnocythere sp. and Eucypris aff. fontana are typical species of permanent ponds and lakes. Isotope values indicate high degree of evaporation of lake waters relative to feeder springs and streams and range between -7 and +5 per mil for oxygen, and -5 and +4 per mil for carbon. Limnocythere rionegroensis is the dominant species in ephemeral ponds and lakes. These systems display the most enriched isotope values in both ostracodes and host waters, extending from -5 to +7 per mil for oxygen, and from -5 to +6 per mil for carbon. Living ostracodes show a positive offset from equilibrium values of up to 2 per mil for oxygen. Carbon-isotope values are up to 6? more negative than equilibrium values in highly productive pools. Comparison of ostracode and host water isotope signals permits assessment of the life span of the aquatic environments. Valves from dead ostracodes collected from ephemeral ponds and lakes show a wide scatter with each sample providing a snapshot of the seasonal history of the host water. The presence of the stream species Ilyocypris ramirezi and a wide range of ostracode isotope values suggest that ephemeral ponds and lakes are fed by streams during spring run-off and seasonally dry. A temporary character is also indicated by Heterocypris incongruens, a drought-resistant species that occupies most springs and seeps. In addition, Limnocythere rionegroensis has adjusted its reproduction strategies to its environment. Whereas only females were collected in fresh host waters, males were found in ephemeral ponds and lakes with higher solute content. Sexual reproduction seems to be the more successful reproduction strategy in high and variable salinities and seasonal droughts. The temporary character of the aquatic environments shows that the availability of meteoric water controls the life span of host waters and underlines the sensitivity of the area to changes in precipitation.

Sucessao geracional na agricultura familiar : Liçoes apreendidas em duas comunidades rurais

The new pattern of modernization of agriculture and rural, in force in most rural areas of Brazil, is also present in the Southwest of Paraná. Thus, considering the marks left by this process, this research tried to see what were the factors that interfere in generational succession and began to influence the family farm's social reproduction strategy. For that, from a qualitative approach, this study sought to compare two rural communities by establishing 25 interviews each and two focus group sessions. The results of this study, it was noticed that the factors that favor the permanence of young people in rural areas were mainly: income, living in society and the inclusion of life projects of the children in the family's social reproduction strategies.