Browsing by Subject "Peru"

Now showing 1 - 3 of 3
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    Measuring social capital and innovation in poor agricultural communities : the case of Cháparra, Peru
    (2011) Arata, Atilio; Hartmann, Dominik
    In the last decades substantive advance has been made in the measurement and understanding of frontier innovation in highly industrialized settings. However, little research focused on the process of learning and the introduction of novelties in smallholder farming of poor agricultural communities. Considering that 1.5 billion people in developing countries live in such smallholder households this is an essential shortcoming. In addressing three crucial questions about the measurement and promotion of endogenous local development this paper contributes to close this research gap. The three questions are: a) how can we measure social capital and innovation in poor agricultural communities, b) what is the impact of external agents on local structures and c) what are the relations between the social capital and the innovative performance of the farmer. In a first step a comprehensive questionnaire with 89 questions on diverse dimensions of social capital and innovation has been elaborated and applied to the agricultural valley of Cháparra in the South of Peru. The results allow for an indepth analysis of the capabilities, network position and innovative behavior of the farmers. In a second step, we apply social network analysis techniques to analyze the role and position of the relevant actors in the local as well as in the external technical information networks with a special focus on the influence of an external NGO. The analysis reveals a deep structural impact of the NGO and significant correlations between the network position of the farmers and their innovative performance. Three crucial issues for research on smallholder innovation are identified. First, diverse dimensions of social capital and innovation have to be differentiated when studying endogenous development. Second, it has to be assessed to which degree the modification of the existing social structures by external agents can be harmful or beneficial. Third, social network analysis can help us to gain a better understanding of the complex relations between social capital and innovation and how these can contribute to foster sustainable development projects.
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    Peru Botanische Exkursion 2008
    (2010) Dinter, Ina; Zimmermann, Reiner
    The botanical excursion to Peru, a global hotspot of biodiversity, provides an overview of the climatic, regional and plant ecological situation of the equatorial neotropics. The areas visited cover the hyper arid coastal deserts, the dry and cold andine Puna, the Amazon lowland rainforests and the seasonal dry forests of North Peru. The excursion report presented was compiled from presentations and protocols of the participants and contains the list of plants found at each site visited.
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    Radial tree growth dynamics and xylem anatomy along an elevational gradient in the El Sira Mountains, Peru
    (2019) Niessner, Armin; Küppers, Manfred
    The explicit purpose of this study was to (1) characterize climate and vegetation along the western slope of the Cerros del Sira (Peru), (2) evaluate radial tree growth along this slope in response to seasonal rainfall anomalies, (3) reveal how the meteorological environment controls tree radial stem growth, and (4) to investigate how xylem anatomy relates to dynamics of tree growth. From May 2011 until September 2015, radial stem growth of 67 trees was monitored using point-dendrometers, and meteorological parameters were measured within five sites along an elevational gradient. Additionally, tree dimensions (stem diameter, stem height) and xylem anatomical traits (mean vessel diameter, vessel frequency, cumulative vessel area and potential hydraulic conductivity) were determined. The transect extends from lowland terra firme forests (ca. 250 m asl) over submontane forests, late and mid successional montane cloud forests up to exposed elfin forests (ca. 2200 m asl). Continuous rainfall records for remote tropical areas are extremely rare and measurements along this transect are also incomplete. Monthly rainfall estimates by the TRMM PR satellite ("product 3B42") were highly correlated with rain gauge observations, although they underestimate rainfall at high elevations. Different intra-annual tree growth patterns could be identified within each elevational forest type, showing species/individuals with seasonally independent continuous or alternating growth patterns and strictly seasonal growth. Stem growth at each site was typically higher during rainy seasons, except for in the elfin forest. The rainy season from October 2013 to March 2014 was extraordinarily dry, with only 73 % of long-term mean precipitation received, which resulted in reduced tree radial growth rates, again with the exception of the elfin forest. Different analytical approaches revealed that precipitation is the main growth-controlling factor at lower elevations, especially during rainy seasons. Growth within montane and cloud forests positively correlates to solar radiation. Tree growth within the elfin forest is only weakly correlated to meteorological parameters, but dry conditions during dry seasons promote growth. It was hypothesized that (1) individuals/species with large vessel diameters and low vessel frequencies have higher radial growth rates, but are more vulnerable to relatively dry periods. Therefore, (2) they are more likely to grow seasonally and predominantly during rainy seasons, (3) their growth during the exceptionally dry rainy season 2013/14 was more constrained, and (4) their growth is generally closer correlated to meteorological parameters. Larger trees tend to have larger vessel diameters, which positively relates to radial growth rates, and they also tend to grow more seasonal. As hypothesized, trees having large vessel diameters are more sensitive to droughts, as indicated by stronger positive correlations with rainfall and negative with solar radiation. However, in mountainous forests, relations between xylem anatomical traits and tree growth dynamics seem to be more complex. In late-successional cloud forests, growth of trees with large vessel diameter is positively, while of trees with small vessel diameter negatively related to solar radiation. Sensitivity to the dry rainy season 2013/14, expressed as relative reduction in growth compared to "normal" rainy seasons, could not be explained by xylem anatomical traits, contradicting the preceded hypothesis. Tropical lowland rainforest species, especially individuals with large vessels, will likely suffer from increasing drought frequencies and intensities. How montane forest ecosystems will react to a (globally) changing climate is rather uncertain, especially in exposed elfin forests. Results of this study suggest that species of late-successional tropical montane forests may profit from higher temperatures. While montane tropical rain forests may also suffer from prolonged droughts, exposed ridges covered by elfin forests still receive plenty of precipitation and may benefit from receiving more solar radiation for photosynthesis and, thus, grow faster.