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11.
O. Dangles F. C. Carpio M. Villares F. Yumisaca B. Liger F. Rebaudo J. F. Silvain 《Ambio》2010,39(4):325-335
Participatory research has not been a conspicuous methodology in developing nations for studying invasive pests, an increasing
threat to the sustainable development in the tropics. Our study presents a community-based monitoring system that focuses
on three invasive potato tuber moth species (PTM). The monitoring was developed and implemented by young farmers in a remote
mountainous area of Ecuador. Local participants collected data from the PTM invasion front, which revealed clear connection
between the abundance of one of the species (Tecia solanivora) and the remoteness to the main market place. This suggests that mechanisms structuring invasive populations at the invasion
front are different from those occurring in areas invaded for longer period. Participatory monitoring with local people may
serve as a cost-effective early warning system to detect and control incipient invasive pest species in countries where the
daily management of biological resources is largely in the hands of poor rural people. 相似文献
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Abstract: Determining the permeability of different types of landscape matrices to animal movement is essential for conserving populations in fragmented landscapes. We evaluated the effects of habitat patch size and matrix type on diversity, isolation, and dispersal of ithomiine butterflies in forest fragments surrounded by coffee agroecosystems in the Colombian Andes. Because ithomiines prefer a shaded understory, we expected the highest diversity and abundance in large fragments surrounded by shade coffee and the lowest in small fragments surrounded by sun coffee. We also thought shade coffee would favor butterfly dispersal and immigration into forest patches. We marked 9675 butterflies of 39 species in 12 forest patches over a year. Microclimate conditions were more similar to the forest interior in the shade‐coffee matrix than in the sun‐coffee matrix, but patch size and matrix type did not affect species richness and abundance in forest fragments. Furthermore, age structure and temporal recruitment patterns of the butterfly community were similar in all fragments, independent of patch size or matrix type. There were no differences in the numbers of butterflies flying in the matrices at two distances from the forest patch, but their behavior differed. Flight in the sun‐coffee matrix was rapid and directional, whereas butterflies in shade‐coffee matrix flew slowly. Seven out of 130 recaptured butterflies immigrated into patches in the shade‐coffee matrix, and one immigrated into a patch surrounded by sun coffee. Although the shade‐coffee matrix facilitated movement in the landscape, sun‐coffee matrix was not impermeable to butterflies. Ithomiines exhibited behavioral plasticity in habitat use and high mobility. These traits favor their persistence in heterogeneous landscapes, opening opportunities for their conservation. Understanding the dynamics and resource requirements of different organisms in rural landscapes is critical for identifying management options that address both animals’ and farmers’ needs. 相似文献
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The development of the mercury (Hg) amalgamation process in the mid-sixteenth century triggered the onset of large-scale Hg
mining in both the Old and New Worlds. However, ancient Hg emissions associated with amalgamation and earlier mining efforts
remain poorly constrained. Using a geochemical time-series generated from lake sediments near Cerro Rico de Potosí, once the
world’s largest silver deposit, we demonstrate that pre-Colonial smelting of Andean silver ores generated substantial Hg emissions
as early as the twelfth century. Peak sediment Hg concentrations and fluxes are associated with smelting and exceed background
values by approximately 20-fold and 22-fold, respectively. The sediment inventory of this early Hg pollution more than doubles
that associated with extensive amalgamation following Spanish control of the mine (1574–1900 AD). Global measurements of [Hg]
from economic ores sampled world-wide indicate that the phenomenon of Hg enrichment in non-ferrous ores is widespread. The
results presented here imply that indigenous smelting constitutes a previously unrecognized source of early Hg pollution,
given naturally elevated [Hg] in economic silver deposits. 相似文献
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南安第斯中生代构造演化化以形成哈迪(Hardy}弧—洛卡斯维尔德斯(Rocas Verdes)盆体系为主要特征。当地出露的陶比发拉(Tobifera)组、陶凸哈(Tortuga)蛇绿杂岩、亚汗(Yahgan)组和哈迪组分别代表了残余陆缘弧、T型大洋中脊、弧后盆地和岛弧上发育的岩石组合。弧—盆演化过程中,地幔物质底辟上隆造成早期陆缘弧一分为二,其一西移,形成以之为根的新生火山岛弧;另一部分保存于大陆内部,成为形成于分裂陆缘弧内部的弧后盆地火成碎屑的主要源区。盆地形成中期,裂陷深度大,内部出现洋中脊,基性火成岩沿该洋中脊侵位喷发。 相似文献