Beefing Up Species Richness? The Effect of Land-Use on Mammal Diversity in an Arid Biodiversity Hotspot

2015 ◽  
Vol 45 (3) ◽  
pp. 321-331 ◽  
Author(s):  
Gareth K.H. Mann ◽  
Juliette V. Lagesse ◽  
M. Justin O'Riain ◽  
Dan M. Parker
2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Andreas Ch. Braun ◽  
Fabian Faßnacht ◽  
Diego Valencia ◽  
Maximiliano Sepulveda

AbstractCentral Chile is an important biodiversity hotspot in Latin America. Biodiversity hotspots are characterised by a high number of endemic species cooccurring with a high level of anthropogenic pressure. In central Chile, the pressure is caused by land-use change, in which near-natural primary and secondary forests are replaced and fragmented by commercial pine and eucalyptus plantations. Large forest fires are another factor that can potentially endanger biodiversity. Usually, environmental hazards, such as wildfires, are part of the regular environmental dynamic and not considered a threat to biodiversity. Nonetheless, this situation may change if land-use change and altered wildfire regimes coerce. Land-use change pressure may destroy landscape integrity in terms of habitat loss and fragmentation, while wildfires may destroy the last remnants of native forests. This study aims to understand the joint effects of land-use change and a catastrophic wildfire on habitat loss and habitat fragmentation of local plant species richness hotspots in central Chile. To achieve this, we apply a combination of ecological fieldwork, remote sensing, and geoprocessing to estimate the spread and spatial patterns of biodiverse habitats under current and past land-use conditions and how these habitats were altered by land-use change and by a single large wildfire event. We show that land-use change has exceeded the wildfire’s impacts on diverse habitats. Despite the fact that the impact of the wildfire was comparably small here, wildfire may coerce with land-use change regarding pressure on biodiversity hotspots. Our findings can be used to develop restoration concepts, targeting on an increase of habitat diversity within currently fire-cleared areas and evaluate their benefits for plant species richness conservation.


Author(s):  
Vassiliki Kati ◽  
Christina Kassara ◽  
Zoi Vrontisi ◽  
Aristides Moustakas

Weed Science ◽  
2007 ◽  
Vol 55 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Lynn M. Sosnoskie ◽  
Edward C. Luschei ◽  
Mark A. Fanning

The importance of managing weeds in seminatural habitats that are adjacent to farm fields is unclear. Weedy-margin vegetation may harbor pests or pathogens and may ALSo serve as source populations for ongoing immigration of weeds into the field. It is ALSo possible, however, that margin vegetation provides habitat for organisms that consume weed seeds or suppress the likelihood of pest or pathogen outbreak. We examined the nature of margin habitat using spatial-scaling of Weed-Species richness as an ecological assay. In 2003, we recorded the occurrence of weedy species along the perimeters of 63 fields in Wisconsin. The fields were distributed within six counties that differed in topography, geological history, local climate, and soil type and which spanned the range of variability in the agricultural landscape. We identified seven habitats that differed in geology and land use. The relationship between species richness and margin class was estimated using an analog of the power law. Additionally, we investigated broadscale correlates of habitat heterogeneity at the field level, using a modeling strategy that included additional explanatory factors logically connected to plant diversity. Using a model-confrontation approach, the survey supported the inclusion of two topographical diversity indices, elevation gradient and a field-shape index, into our model. Our broadscale survey provides information on one of a suite of important considerations needed to make decisions about the importance of managing weeds in field margins.


Biologia ◽  
2015 ◽  
Vol 70 (1) ◽  
Author(s):  
Małgorzata Kolicka ◽  
Marcin Krzysztof Dziuba ◽  
Krzysztof Zawierucha ◽  
Natalia Kuczyńska–Kippen ◽  
Lech Kotwicki

AbstractGreenhouses form favourable conditions for establishing stable populations of native as well as invasive alien microinvertebrates. Investigations of palm houses have a long tradition and native, alien and new species for science have been found in many of them. The examined pond and some microreservoirs in Bromeliaceae and Agavoideae in Pozna´n Palm House (Poland) sampled in 2012, appeared to contain representatives of Rotifera (64 species), Copepoda (2 species), Polychaeta, Acari and Insecta larvae. The most abundant Rotifera species were: Anuraeopsis fissa Gosse, 1851, Ascomorpha ecaudis Perty 1850, Euchlanis dilatata Ehrenberg, 1832, Pompholyx sulcata Hudson, 1885 and Trichocerca rousseleti Voight, 1902. Moreover, rotifers considered to be rare in Poland, i.e., Asplanchna herricki De Guerne, 1888, Collotheca pelagica Rousselet, 1893, Colurella sulcata Stenroos, 1898, Gastropus minor Rousselet, 1892 were also detected in Pozna´n Palm House. Two recorded Copepoda species were Phyllognathopus viguieri (Maupas, 1892) found in agave microreservoirs and Mesocyclops leuckarti (Claus, 1857) found in reservoir with aquatic plants. For biodiversity evaluation of rotifers Margalef’s and Shannon-Wiener’s indexes were used and in order to determine species richness the Simpson index was calculated. Additionally, a complete list of all aquatic invertebrates is presented, i.e., Plathelmintes (11 species), Nemeretea (2 species), Oligochatea (13 taxa), Polychaeta (7 species), Gastrotricha (13 taxa) and Copepoda (1 species) previously recorded in Pozna´n Palm House. To sum up, Palm houses create a convenient habitat for a prevalence of native and introduced invertebrates and are a putative source of alien species, possibly facilitating their release to the environment.


2011 ◽  
Vol 41 (8) ◽  
pp. 1687-1697 ◽  
Author(s):  
Lee Jacobs ◽  
Jeff E. Houlahan

Here, we examine the effects of adjacent land use in a managed forest on pond-breeding amphibian species richness and community composition at 34 New Brunswick, Canada, ponds. Amphibian species richness was negatively correlated with the proportion of roads, precommercial thinning, and hardwood forest and positively correlated with the proportion of wetlands in adjacent lands. These land-use effects peak at 180 m from the ponds. Road density was negatively correlated with Lithobates catesbeiana and Lithobates septentrionalis presence. Precommercial thinning was negatively correlated with Ambystoma spp. presence and positively correlated with Anaxyrus americanus presence. Wetlands were positively correlated with L. septentrionalis and Notopthalamus viridescens presence. Correlations were also found between water table height and A. americanus, Lithobates palustris , and Ambystoma spp. presence. In addition, L. catesbeiana and N. viridescens presence–absence was positively correlated with the proportion of mature and overmature forest on the landscape (at scales of 500 and 1000 m, respectively). Lastly, the proportion of regenerating and sapling forest on the landscape was negatively correlated with L. palustris presence–absence but, by contrast, was positively correlated with A. americanus. These results suggest that the effects of adjacent land use may significantly impact amphibian populations in managed eastern Canadian forests.


2018 ◽  
Vol 44 (2) ◽  
pp. 313-326 ◽  
Author(s):  
Keila Caroline Dalle Laste ◽  
Giselda Durigan ◽  
Alan N. Andersen

2018 ◽  
Vol 11 (2) ◽  
pp. 78-84 ◽  
Author(s):  
Agno Nonato Serrão Acioli

Resumo. Os cupins são importantes decompositores da matéria de origem vegetal. Este estudo teve como objetivo analisar e comparar a diversidade e composição das espécies de cupins em três diferentes sistemas de uso do solo na região do Alto Solimões, Amazonas, Brasil. Os cupins foram coletados na floresta primária, em cultivos de dendê (Elaeis guineensis Jacq.) e mandioca (Manihot sculenta Crantz). Em cada área selecionada as coletas foram realizadas dentro de um transecto retangular medindo 100 m x 2 m, subdivididos em 20 parcelas de 5 m x 2 m. Foram encontradas 24 espécies de cupins, pertencentes a 14 gêneros e duas famílias, nos três sistemas de uso do solo. As espécies mais frequentes foram Nasutitermes cf. dendrophilus (Desneux) (28,43%), seguida de Heterotermes tenuis (Hagen) (14,37%) e Anoplotermes sp. 2 (9,58%). A riqueza de espécies foi maior na floresta primária (16 espécies), seguida dos cultivos de dendê (14 espécies) e mandioca (seis espécies). A composição taxonômica e os grupos funcionais também sofreram modificações, sendo mais diversificados e equilibrados na floresta primária quando comparados com os dois tipos de cultivos. A comunidade de cupins é fortemente afetada quando ocorre a substituição da floresta primária pelos cultivos agrícolas. Neste estudo, as espécies N. cf. dendrophilus e H. tenuis merecem atenção, pois se constata o aumento de sua frequência nos cultivos de dendê e mandioca.Frequency, Diversity and Composition of Termite Fauna (Blattodea: Isoptera) in Land Use Systems in the Southwest of Amazonas, Brazil Abstract. Termites are important decomposers of matter of vegetable origin. This study aims to analyze and compare the diversity and composition of termite species in three different land use systems in Alto Solimões, Amazonas, Brazil. Termites were collected in the primary forest, oil palm (Elaeis guineensis Jacq.) and cassava (Manihot sculenta Crantz) crops. In each area the collections were made within a rectangular transect measuring 100 m x 2 m, subdivided into 20 plots of 5 m x 2 m. Twenty four species of termites were found, belonging to 14 genera and two families. The most frequent species were Nasutitermes cf. dendrophilus (Desneux) (28.43%), Heterotermes tenuis (Hagen) (14.37%) and Anoplotermes sp. 2 (9.58%). The species richness was higher in the primary forest (16 species), followed by oil palm (14 species) and cassava (six species) crops. The taxonomic composition and the functional groups were also modified, being more diversified and balanced in the primary forest than in the crops. The termite community was strongly affected when the primary forest was replaced by agricultural crops. The species N. cf. dendrophilus and H. tenuis deserve attention, it was verified the increase of their frequency in the crops.


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