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1.
Conserv Biol ; 23(3): 578-87, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19236450

RESUMO

Conservation efforts are only as sustainable as the social and political context within which they take place. The weakening or collapse of sociopolitical frameworks during wartime can lead to habitat destruction and the erosion of conservation policies, but in some cases, may also confer ecological benefits through altered settlement patterns and reduced resource exploitation. Over 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots, and more than 80% took place directly within hotspot areas. Less than one-third of the 34 recognized hotspots escaped significant conflict during this period, and most suffered repeated episodes of violence. This pattern was remarkably consistent over these 5 decades. Evidence from the war-torn Eastern Afromontane hotspot suggests that biodiversity conservation is improved when international nongovernmental organizations support local protected area staff and remain engaged throughout the conflict. With biodiversity hotspots concentrated in politically volatile regions, the conservation community must maintain continuous involvement during periods of war, and biodiversity conservation should be incorporated into military, reconstruction, and humanitarian programs in the world's conflict zones.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Guerra , África Oriental , Organizações
2.
Mol Ecol ; 17(8): 2060-73, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18373529

RESUMO

In the face of widespread deforestation, the conservation of rainforest trees relies increasingly on their ability to maintain reproductive processes in fragmented landscapes. Here, we analysed nine microsatellite loci for 218 adults and 325 progeny of the tree Dipteryx panamensis in Costa Rica. Pollen dispersal distances, genetic diversity, genetic structure and spatial autocorrelation were determined for populations in four habitats: continuous forest, forest fragments, pastures adjacent to fragments and isolated pastures. We predicted longer but less frequent pollen movements among increasingly isolated trees. This pattern would lead to lower outcrossing rates for pasture trees, as well as lower genetic diversity and increased structure and spatial autocorrelation among their progeny. Results generally followed these expectations, with the shortest pollen dispersal among continuous forest trees (240 m), moderate distances for fragment (343 m) and adjacent pasture (317 m) populations, and distances of up to 2.3 km in isolated pastures (mean: 557 m). Variance around pollen dispersal estimates also increased with fragmentation, suggesting altered pollination conditions. Outcrossing rates were lower for pasture trees and we found greater spatial autocorrelation and genetic structure among their progeny, as well as a trend towards lower heterozygosity. Paternal reproductive dominance, the pollen contributions from individual fathers, did not vary among habitats, but we did document asymmetric pollen flow between pasture and adjacent fragment populations. We conclude that long-distance pollen dispersal helps maintain gene flow for D. panamensis in this fragmented landscape, but pasture and isolated pasture populations are still at risk of long-term genetic erosion.


Assuntos
Dipteryx/genética , Ecossistema , Pólen/genética , Alelos , Costa Rica , DNA de Plantas/química , DNA de Plantas/genética , Variação Genética , Genótipo , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Clima Tropical
3.
Ann N Y Acad Sci ; 1429(1): 50-65, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29683517

RESUMO

The activities involved in preparing for, executing, and recovering from armed conflict are globally pervasive and consequential, with significant impacts on natural systems. Effects on biodiversity are predominantly negative, produced by direct and indirect battlefield impacts, as well as the general breakdown of social, economic, and governance systems during wartime. Certain conservation opportunities do occur, however, particularly on lands set aside for training exercises, buffer zones, and peace parks. Here, the relationship between armed conflict and biodiversity is reviewed using the temporal framework of warfare ecology, which defines warfare as an ongoing process of three overlapping stages: preparations, war (armed conflict), and postwar activities. Several themes emerge from recent studies, including a heightened awareness of biodiversity conservation on military lands, the potential for scientific and conservation engagement to mitigate negative biodiversity impacts in war zones, and the importance of the postwar period for incorporating biodiversity priorities into reconstruction and recovery efforts. Research limitations and knowledge gaps are also discussed.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecologia , Guerra , Humanos
4.
Ecol Evol ; 4(9): 1524-37, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24967073

RESUMO

Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species linked to plots in fragments within a partially forested landscape. The database currently holds 9830 unique species recorded in plots of 58 unique landscapes in six of eight realms: mammals 315, birds 1286, herptiles 460, insects 4521, spiders 204, other arthropods 85, gastropods 70, annelids 8, platyhelminthes 4, Onychophora 2, vascular plants 2112, nonvascular plants and lichens 320, and fungi 449. Three landscapes were sampled as long-term time series (>10 years). Seven hundred and eleven species are found in two or more landscapes. Consolidating the substantial amount of primary data available on biodiversity responses to fragmentation in the context of land-use change and natural disturbances is an essential part of understanding the effects of increasing anthropogenic pressures on land. The consistent format of this database facilitates testing of generalizations concerning biologic responses to fragmentation across diverse systems and taxa. It also allows the re-examination of existing datasets with alternative landscape metrics and robust statistical methods, for example, helping to address pseudo-replication problems. The database can thus help researchers in producing broad syntheses of the effects of land use. The database is dynamic and inclusive, and contributions from individual and large-scale data-collection efforts are welcome.

5.
Mol Ecol Resour ; 8(2): 425-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21585810

RESUMO

The almendro (Dipteryx panamensis, Fabaceae) is a tetraploid tree native to the Atlantic lowland rainforests of Central America. We present nine microsatellite primer pairs amplified in three multiplexed reactions for 549 individuals from four sites in Costa Rica. All loci were polymorphic, ranging from three to 13 alleles per locus. Expected heterozygosity was estimated with the program tetrasat, and ranged from 0.21 to 0.74 across loci. These markers will be used for estimating pollen dispersal, seed dispersal, genetic structure and genetic diversity in fragmented landscapes.

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