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1.
Glob Chang Biol ; 21(2): 973-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25242445

RESUMO

Soil biodiversity plays a key role in regulating the processes that underpin the delivery of ecosystem goods and services in terrestrial ecosystems. Agricultural intensification is known to change the diversity of individual groups of soil biota, but less is known about how intensification affects biodiversity of the soil food web as a whole, and whether or not these effects may be generalized across regions. We examined biodiversity in soil food webs from grasslands, extensive, and intensive rotations in four agricultural regions across Europe: in Sweden, the UK, the Czech Republic and Greece. Effects of land-use intensity were quantified based on structure and diversity among functional groups in the soil food web, as well as on community-weighted mean body mass of soil fauna. We also elucidate land-use intensity effects on diversity of taxonomic units within taxonomic groups of soil fauna. We found that between regions soil food web diversity measures were variable, but that increasing land-use intensity caused highly consistent responses. In particular, land-use intensification reduced the complexity in the soil food webs, as well as the community-weighted mean body mass of soil fauna. In all regions across Europe, species richness of earthworms, Collembolans, and oribatid mites was negatively affected by increased land-use intensity. The taxonomic distinctness, which is a measure of taxonomic relatedness of species in a community that is independent of species richness, was also reduced by land-use intensification. We conclude that intensive agriculture reduces soil biodiversity, making soil food webs less diverse and composed of smaller bodied organisms. Land-use intensification results in fewer functional groups of soil biota with fewer and taxonomically more closely related species. We discuss how these changes in soil biodiversity due to land-use intensification may threaten the functioning of soil in agricultural production systems.


Assuntos
Agricultura/métodos , Biodiversidade , Microbiologia do Solo , Europa (Continente)
2.
Front Psychol ; 12: 644240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646186

RESUMO

Climate change involves multiple emotional expressions associated with specific labels, notably: 'concern,' 'guilt,' or 'scepticism.' However, there are other types of emotions that have been less analysed, such as 'powerlessness,' 'anger' and 'confusion' that are of equal importance for predicting behavioural changes toward this climatic issue. Likewise, few studies in this research field rely on qualitative data to understand and identify the causative agents for the emotional arousal. This research explores a range of emotions, mixing those that have been widely studied and those that have been hardly analysed. It also looks at the demographic parameters associated with such emotions using a population sample from southern Ecuador. The study analyses quantitative and qualitative data gathered through structured-questionnaires whereby participants were given agency to select and define how they themselves sense emotionally climate change. The results indicate that two of the five participants' most selected emotions are shared with other nations ('concern,' 'guilt'), while the other three have been less reported and studied in the climate change field ('powerlessness,' 'anger,' and 'confusion'). These emotions were found to be aroused by different reasons associated with specific demographic variables. The findings reveal the role of the cultural and local environment in the emotional arousal and its relevance for designing more effective climate communication campaigns.

3.
Public Underst Sci ; 29(7): 745-756, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32627675

RESUMO

For decades, researchers have worried about people's understanding of climate change. Although this understanding varies by cultural context, most studies so far have taken place in industrialised countries. Few studies have explored understandings of climate change in the global South. Through standardised questionnaires and semi-structured interviews conducted in southern Ecuador, this article explores differences between urban and rural dwellers and compares these with farmers' understandings of the causes, consequences and risks. We found urban and rural dwellers hold a similar understanding to that found in other nations, but articulated in ways that reflect their particular realities. Despite reporting firsthand experience of the agricultural effects of climate change, when prompted, farmers do not link climate change to their own experience. It is thus important to go beyond judging knowledge as correct or incorrect, and instead, incorporate local realities in the climate narrative.


Assuntos
Mudança Climática , Fazendeiros , Agricultura , Equador , Humanos , População Rural
4.
Ecol Lett ; 11(6): 564-75, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18363716

RESUMO

We analysed the dynamics of a plant-pollinator interaction network of a scrub community surveyed over four consecutive years. Species composition within the annual networks showed high temporal variation. Temporal dynamics were also evident in the topology of the network, as interactions among plants and pollinators did not remain constant through time. This change involved both the number and the identity of interacting partners. Strikingly, few species and interactions were consistently present in all four annual plant-pollinator networks (53% of the plant species, 21% of the pollinator species and 4.9% of the interactions). The high turnover in species-to-species interactions was mainly the effect of species turnover (c. 70% in pairwise comparisons among years), and less the effect of species flexibility to interact with new partners (c. 30%). We conclude that specialization in plant-pollinator interactions might be highly overestimated when measured over short periods of time. This is because many plant or pollinator species appear as specialists in 1 year, but tend to be generalists or to interact with different partner species when observed in other years. The high temporal plasticity in species composition and interaction identity coupled with the low variation in network structure properties (e.g. degree centralization, connectance, nestedness, average distance and network diameter) imply (i) that tight and specialized coevolution might not be as important as previously suggested and (ii) that plant-pollinator interaction networks might be less prone to detrimental effects of disturbance than previously thought. We suggest that this may be due to the opportunistic nature of plant and animal species regarding the available partner resources they depend upon at any particular time.


Assuntos
Adaptação Biológica/fisiologia , Ecossistema , Insetos/fisiologia , Modelos Biológicos , Fenômenos Fisiológicos Vegetais , Polinização/fisiologia , Animais , Grécia , Observação , Especificidade da Espécie
5.
PLoS One ; 13(1): e0189843, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29320514

RESUMO

Acoustic diversity indices have been proposed as low-cost biodiversity monitoring tools. The acoustic diversity of a soundscape can be indicative of the richness of an acoustic community and the structural/vegetation characteristics of a habitat. There is a need to apply these methods to landscapes that are ecologically and/or economically important. We investigate the relationship between the acoustic properties of a coniferous forest with stand-age and structure. We sampled a 73 point grid in part of the UK's largest man-made lowland coniferous plantation forest, covering a 320ha mosaic of different aged stands. Forest stands ranged from 0-85 years old providing an age-gradient. Short soundscape recordings were collected from each grid point on multiple mornings (between 6am-11am) to capture the dawn chorus. We repeated the study during July/August in 2014 and again in 2015. Five acoustic indices were calculated for a total of 889 two minute samples. Moderate relationships between acoustic diversity with forest stand-age and vegetation characteristics (canopy height; canopy cover) were observed. Ordinations suggest that as structural complexity and forest age increases, the higher frequency bands (4-10KHz) become more represented in the soundscape. A strong linear relationship was observed between distance to the nearest road and the ratio of anthropogenic noise to biological sounds within the soundscape. Similar acoustic patterns were observed in both years, though acoustic diversity was generally lower in 2014, which was likely due to differences in wind conditions between years. Our results suggest that developing these relatively low-cost acoustic monitoring methods to inform adaptive management of production landscapes, may lead to improved biodiversity monitoring. The methods may also prove useful for modelling road noise, landscape planning and noise mitigation.


Assuntos
Biodiversidade , Monitoramento Ambiental/métodos , Florestas , Ruído , Traqueófitas , Conservação dos Recursos Naturais
6.
Int J Primatol ; 38(2): 282-302, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28546651

RESUMO

Many primate populations inhabit anthropogenic landscapes. Understanding their long-term ability to persist in such environments and associated real and perceived risks for both primates and people is essential for effective conservation planning. Primates in forest-agricultural mosaics often consume cultivars to supplement their diet, leading to potentially negative encounters with farmers. When crossing roads, primates also face the risk of encounters with people and collision with vehicles. Chimpanzees (Pan troglodytes verus) in Bossou, Guinea, West Africa, face such risks regularly. In this study, we aimed to examine their activity budget across habitat types and the influence of anthropogenic risks associated with cultivated fields, roads, and paths on their foraging behavior in noncultivated habitat. We conducted 6-h morning or afternoon follows daily from April 2012 to March 2013. Chimpanzees preferentially used forest habitat types for traveling and resting and highly disturbed habitat types for socializing. Wild fruit and crop availability influenced seasonal habitat use for foraging. Overall, chimpanzees preferred mature forest for all activities. They showed a significant preference for foraging at >200 m from cultivated fields compared to 0-100 m and 101-200 m, with no effect of habitat type or season, suggesting an influence of associated risk. Nevertheless, the chimpanzees did not actively avoid foraging close to roads and paths. Our study reveals chimpanzee reliance on different habitat types and the influence of human-induced pressures on their activities. Such information is critical for the establishment of effective land use management strategies in anthropogenic landscapes.

7.
PLoS One ; 11(5): e0153973, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27144280

RESUMO

Large carnivores such as jaguars (Panthera onca) are species of conservation concern because they are suffering population declines and are keystone species in their ecosystems. Their large area requirements imply that unprotected and ever-increasing agricultural regions can be important habitats as they allow connectivity and dispersal among core protected areas. Yet information on jaguar densities across unprotected landscapes it is still scarce and crucially needed to assist management and range-wide conservation strategies. Our study provides the first jaguar density estimates of Colombia in agricultural regions which included cattle ranching, the main land use in the country, and oil palm cultivation, an increasing land use across the Neotropics. We used camera trapping across two agricultural landscapes located in the Magdalena River valley and in the Colombian llanos (47-53 stations respectively; >2000 trap nights at both sites) and classic and spatially explicit capture-recapture models with the sex of individuals as a covariate. Density estimates were 2.52±0.46-3.15±1.08 adults/100 km2 in the Magdalena valley, whereas 1.12±0.13-2.19±0.99 adults/100 km2 in the Colombian llanos, depending on analysis used. We suggest that jaguars are able to live across unprotected human-use areas and co-exist with agricultural landscapes including oil-palm plantations if natural areas and riparian habitats persist in the landscape and hunting of both jaguar and prey is limited. In the face of an expanding agriculture across the tropics we recommend land-use planning, adequate incentives, regulations, and good agricultural practices for range-wide jaguar connectivity and survival.


Assuntos
Panthera/fisiologia , Agricultura/métodos , Animais , Bovinos , Colômbia , Conservação dos Recursos Naturais/métodos , Ecossistema , Humanos , Densidade Demográfica
8.
PLoS One ; 11(6): e0156481, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27276218

RESUMO

Reducing Emissions from Deforestation and forest Degradation (REDD+) aims to avoid forest conversion to alternative land-uses through financial incentives. Oil-palm has high opportunity costs, which according to current literature questions the financial competitiveness of REDD+ in tropical lowlands. To understand this more, we undertook regional fine-scale and coarse-scale analyses (through carbon mapping and economic modelling) to assess the financial viability of REDD+ in safeguarding unprotected forest (30,173 ha) in the Lower Kinabatangan floodplain in Malaysian Borneo. Results estimate 4.7 million metric tons of carbon (MgC) in unprotected forest, with 64% allocated for oil-palm cultivations. Through fine-scale mapping and carbon accounting, we demonstrated that REDD+ can outcompete oil-palm in regions with low suitability, with low carbon prices and low carbon stock. In areas with medium oil-palm suitability, REDD+ could outcompete oil palm in areas with: very high carbon and lower carbon price; medium carbon price and average carbon stock; or, low carbon stock and high carbon price. Areas with high oil palm suitability, REDD+ could only outcompete with higher carbon price and higher carbon stock. In the coarse-scale model, oil-palm outcompeted REDD+ in all cases. For the fine-scale models at the landscape level, low carbon offset prices (US $3 MgCO2e) would enable REDD+ to outcompete oil-palm in 55% of the unprotected forests requiring US $27 million to secure these areas for 25 years. Higher carbon offset price (US $30 MgCO2e) would increase the competitiveness of REDD+ within the landscape but would still only capture between 69%-74% of the unprotected forest, requiring US $380-416 million in carbon financing. REDD+ has been identified as a strategy to mitigate climate change by many countries (including Malaysia). Although REDD+ in certain scenarios cannot outcompete oil palm, this research contributes to the global REDD+ debate by: highlighting REDD+ competitiveness in tropical floodplain landscapes; and, providing a robust approach for identifying and targeting limited REDD+ funds.


Assuntos
Arecaceae/crescimento & desenvolvimento , Conservação dos Recursos Naturais/economia , Produção Agrícola/economia , Florestas , Bornéu
9.
PLoS One ; 9(6): e95388, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24887555

RESUMO

Lowland tropical forests are increasingly threatened with conversion to oil palm as global demand and high profit drives crop expansion throughout the world's tropical regions. Yet, landscapes are not homogeneous and regional constraints dictate land suitability for this crop. We conducted a regional study to investigate spatial and economic components of forest conversion to oil palm within a tropical floodplain in the Lower Kinabatangan, Sabah, Malaysian Borneo. The Kinabatangan ecosystem harbours significant biodiversity with globally threatened species but has suffered forest loss and fragmentation. We mapped the oil palm and forested landscapes (using object-based-image analysis, classification and regression tree analysis and on-screen digitising of high-resolution imagery) and undertook economic modelling. Within the study region (520,269 ha), 250,617 ha is cultivated with oil palm with 77% having high Net-Present-Value (NPV) estimates ($413/ha-yr-$637/ha-yr); but 20.5% is under-producing. In fact 6.3% (15,810 ha) of oil palm is commercially redundant (with negative NPV of $-299/ha-yr-$-65/ha-yr) due to palm mortality from flood inundation. These areas would have been important riparian or flooded forest types. Moreover, 30,173 ha of unprotected forest remain and despite its value for connectivity and biodiversity 64% is allocated for future oil palm. However, we estimate that at minimum 54% of these forests are unsuitable for this crop due to inundation events. If conversion to oil palm occurs, we predict a further 16,207 ha will become commercially redundant. This means that over 32,000 ha of forest within the floodplain would have been converted for little or no financial gain yet with significant cost to the ecosystem. Our findings have globally relevant implications for similar floodplain landscapes undergoing forest transformation to agriculture such as oil palm. Understanding landscape level constraints to this crop, and transferring these into policy and practice, may provide conservation and economic opportunities within these seemingly high opportunity cost landscapes.


Assuntos
Arecaceae/metabolismo , Conservação dos Recursos Naturais , Inundações , Florestas , Óleos de Plantas/metabolismo , Arecaceae/crescimento & desenvolvimento , Conservação dos Recursos Naturais/economia , Geografia , Processamento de Imagem Assistida por Computador , Malásia , Modelos Teóricos , Óleo de Palmeira , Óleos de Plantas/economia
10.
Water Res ; 44(16): 4748-59, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20708770

RESUMO

The Water Framework Directive has caused a paradigm shift towards the integrated management of recreational water quality through the development of drainage basin-wide programmes of measures. This has increased the need for a cost-effective diagnostic tool capable of accurately predicting riverine faecal indicator organism (FIO) concentrations. This paper outlines the application of models developed to fulfil this need, which represent the first transferrable generic FIO models to be developed for the UK to incorporate direct measures of key FIO sources (namely human and livestock population data) as predictor variables. We apply a recently developed transfer methodology, which enables the quantification of geometric mean presumptive faecal coliforms and presumptive intestinal enterococci concentrations for base- and high-flow during the summer bathing season in unmonitored UK watercourses, to predict FIO concentrations in the Humber river basin district. Because the FIO models incorporate explanatory variables which allow the effects of policy measures which influence livestock stocking rates to be assessed, we carry out empirical analysis of the differential effects of seven land use management and policy instruments (fiscal constraint, production constraint, cost intervention, area intervention, demand-side constraint, input constraint, and micro-level land use management) all of which can be used to reduce riverine FIO concentrations. This research provides insights into FIO source apportionment, explores a selection of pollution remediation strategies and the spatial differentiation of land use policies which could be implemented to deliver river quality improvements. All of the policy tools we model reduce FIO concentrations in rivers but our research suggests that the installation of streamside fencing in intensive milk producing areas may be the single most effective land management strategy to reduce riverine microbial pollution.


Assuntos
Monitoramento Ambiental , Fezes/microbiologia , Rios/microbiologia , Microbiologia da Água , Poluição da Água/análise , Abastecimento de Água/análise , Animais , Enterococcus/isolamento & purificação , Recuperação e Remediação Ambiental/métodos , Alimentos/normas , Microbiologia de Alimentos/normas , Humanos , Intestinos/microbiologia , Valor Preditivo dos Testes , Medição de Risco , Estações do Ano , Reino Unido , Abastecimento de Água/normas
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