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1.
Sci Rep ; 10(1): 14800, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908193

RESUMO

To ensure integrity of protected areas we need to understand how species respond to anthropogenic borders. We investigate, from a metacommunity perspective, the direct and indirect mechanisms by which transformed areas affect distribution patterns of ground-living arthropod assemblages inhabiting an extensive protected area adjacent to fruit orchards in an important biosphere reserve. Arthropods and environmental variables were sampled along transects perpendicular to natural-orchard edges. Influence of distance from orchard boundary, degree of impermeability of the boundary, orchard habitat quality (local scale land-use intensity), and edge-induced changes in local environmental variables on arthropod species richness and composition in non-crop habitats were assessed. Arthropod groups were assessed in terms of habitat fidelity: species associated with natural habitat (stenotopic species), those within crop habitat (cultural species), and those showing no preference for either habitat (ubiquitous species). Spillover resulted in higher cultural species richness near edges, but not higher overall species richness. Environmental filtering was important for stenotopic species composition, which was influenced by edge-induced changes in environmental variables. Ubiquitous species composition was determined by orchard impermeability. Increased orchard habitat quality was associated with higher cultural and ubiquitous species richness. The effects of orchards on assemblages in natural habitats can be variable, but predictable when using species habitat specificity in conjunction with a metacommunity framework. High intensity orchards may act as sink habitats, especially for species that readily disperse between crop and natural habitats. Here we recommend that local buffer strips are > 85 m wide, which will reduce the influence of cultural species spillover on sensitive natural ecosystems.


Assuntos
Ecologia , Biodiversidade , Ecossistema
2.
J Environ Manage ; 271: 110922, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778259

RESUMO

Environmental degradation is a global phenomenon with a high likelihood of influencing human quality of life. Effective management responses are needed to achieve societal goals of sustainability. We develop here a new monitoring protocol (Management Check: MATCH) that comprehensively evaluates management outcomes at the operational level. Using the Driver-Pressure-State-Impact-Response (DPSIR) framework, we identified pressures influencing ecosystem integrity inside conservation corridors and commercial compartments of a timber production landscape mosaic. They were 1) domestic livestock grazing (the only exogenous pressure), 2) fire management, 3) invasive alien plants (IAPs), and potential soil erosion from two sources: 4) roads, and 5) harvested timber compartments. We assessed the effects of these on wetland and stream buffers. Environmental incidents accounted for more serious management issues (e.g. oil spills). Management responses were systematically unpacked into point-form questions, which formed the building blocks of our monitoring protocol. We assessed management in twelve plantations in KwaZulu-Natal, South Africa. Answers were compared with Best Operational Practice (BOP), and reworked into a Weighted Index of Compliance (WIC) per section. We found that there was poor management of livestock grazing, but good management of IAPs, roads, and timber compartments. Management of wetland and stream buffers was very good. Fire management presented problems linked to lack of direct effects, measurable at the spatial and temporal scales of operations. We discuss operational outcomes within their respective legislative frameworks, and suggest ways of improving management operations, where needed. MATCH is the first monitoring protocol to comprehensively assess environmental management of commercial forestry at the operational level, and to clearly translate operational activities into measurable progress towards strategic goals. In doing so, MATCH breaks down silos and builds bridges for efficient environmental management in dynamic socio-ecological systems. Moreover, the principles developed here can be applied to build tools that help manage major risks in other economic sectors too. Overall, MATCH strengthened strategic and informed action, which is necessary at multiple levels of an organization, to combat major societal risks, such as environmental degradation.


Assuntos
Ecossistema , Agricultura Florestal , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental , Humanos , Qualidade de Vida , África do Sul
3.
Ecol Appl ; 29(4): e01883, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30847972

RESUMO

Plants often form the basis of conservation planning and management. The effectiveness of plant diversity as a surrogate for arthropod diversity was assessed in natural areas in the Kogelberg Biosphere Reserve, a floral endemism hotspot in the Cape Floristic Region (CFR), South Africa. Arthropods and plants were sampled across 30 topographically heterogeneous sites in a spatially nested design. The relationship between plants and arthropods were quantified in terms of species richness, assemblage variation, and assemblage turnover. The influence of arthropod trophic groups, habitat association, and spatial scale were also explored. Generalized dissimilarity modelling was used to investigate differential influence of explanatory groups (geology, disturbance, local site characteristics, refuge, mesoclimate, terrain) on arthropod and plant turnover. Congruence in assemblage variation was restricted to local scales, and only present between plants and those arthropods associated with the foliar component of the habitat. Weak congruence in species turnover was due to differences in the relative importance of explanatory groups, with different variables within each explanatory group being important, and similar variables predicting different turnover patterns. For both groups, variables related to geology and fire history were important for assemblage turnover. These variables are already incorporated in conservation planning and management for plant diversity across the CFR. Overall plant diversity was a weak surrogate for the arthropod groups included in this study, suggesting that as an alternative, environmental surrogates for arthropod diversity perform better.


Assuntos
Artrópodes , Animais , Biodiversidade , Ecossistema , Plantas , África do Sul
4.
J Environ Manage ; 238: 382-395, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30861399

RESUMO

Habitat degradation is a major concern in transformed landscapes, as it reduces complexity by removing species, interactions, and ultimately biodiversity. Degradation is also of concern for ecological networks (ENs) composed of an interconnected system of conservation corridors among South Africa's commercial forestry compartments. These corridors are predominantly grasslands, and used as rangeland, so managed to optimize grazing conditions. Yet, how this management approach influences biodiversity remains unknown. Here, we studied how butterfly assemblages respond to local differences in rangeland quality (low, high and reference sites), and how this effect compared to that of local environmental variables (e.g. rockiness and bare ground), meso environmental gradients (e.g. topographic position and aspect), and landscape composition (i.e. proportion of different land cover types in the surrounding matrix). We calculated species richness and composition, Shannon's diversity index (H'), and the Butterfly Conservation Index (BCIn) representing the proportion of sensitive and range-restricted butterfly species per site. Rangeland quality was considered less important for butterflies than other environmental variables, but it was also significantly confounded with other environmental variables. At the landscape scale, proportion of grassland in the landscape matrix influenced butterfly assemblage composition, while proportion of thicket had a significant positive effect on BCIn. Moreover, the effect of elevation on assemblage composition emphasizes the value of maintaining environmental gradients within these conservation corridors. At the meso spatial scale, butterfly species richness and diversity (H') declined with increased dominance by a single plant species, which usually occurs late in a normal fire cycle. This suggests a reliance by butterflies on recurring natural disturbances for long-term persistence. We recommend moderate patch burning and grazing, as well as occasional hot burns to reduce thicket in Afromontane grassland. This approach would improve local scale vegetation patterns, and increase heterogeneity across the landscape for conserving these butterflies into the future.


Assuntos
Borboletas , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Pradaria , África do Sul
5.
Persoonia ; 28: 138-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23105159

RESUMO

Novel species of microfungi described in the present study include the following from Australia: Phytophthora amnicola from still water, Gnomoniopsis smithogilvyi from Castanea sp., Pseudoplagiostoma corymbiae from Corymbia sp., Diaporthe eucalyptorum from Eucalyptus sp., Sporisorium andrewmitchellii from Enneapogon aff. lindleyanus, Myrmecridium banksiae from Banksia, and Pilidiella wangiensis from Eucalyptus sp. Several species are also described from South Africa, namely: Gondwanamyces wingfieldii from Protea caffra, Montagnula aloes from Aloe sp., Diaporthe canthii from Canthium inerne, Phyllosticta ericarum from Erica gracilis, Coleophoma proteae from Protea caffra, Toxicocladosporium strelitziae from Strelitzia reginae, and Devriesia agapanthi from Agapanthus africanus. Other species include Phytophthora asparagi from Asparagus officinalis (USA), and Diaporthe passiflorae from Passiflora edulis (South America). Furthermore, novel genera of coelomycetes include Chrysocrypta corymbiae from Corymbia sp. (Australia), Trinosporium guianense, isolated as a contaminant (French Guiana), and Xenosonderhenia syzygii, from Syzygium cordatum (South Africa). Pseudopenidiella piceae from Picea abies (Czech Republic), and Phaeocercospora colophospermi from Colophospermum mopane (South Africa) represent novel genera of hyphomycetes. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

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