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1.
Environ Monit Assess ; 192(8): 503, 2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32648051

RESUMO

This research presents the methodology of mapping a situation of the natural-landscape resources of Khuzestan province in Iran using time-varying space data according to seasonal changes of the indicators of SAVI and LST. The novelty of this research is the combined use of GIS techniques, optical and thermal remote sensing for mapping the situation of the natural-landscape resources aimed at territorial planning. In this research, a classification was carried out for the study area based on the potential of the natural-landscape resources. The Landsat 7 and 8 materials from the periods of 2011-2013 and 2017-2019 were used to perform this research using ERDAS Imagine, ENVI, ArcGIS, and Priznak software. Variations of LST and SAVI were analyzed for 10 seasons of year from April to September. The results showed that both increasing the area of bare soils (wasteland) and residential areas and decreasing the extent of the water resources, forests, and rangeland in Khuzestan province have caused the surface temperature to rise over a period of 9 years. Whereas, matching of the Entisols and Inceptisols with areas having high natural resource potential in Khuzestan province was indicated by the results of this study. And also, the Badlands, Rock-outcrops, and Dunelands are the areas with low natural resource potential. It has been shown that integral indicator of the situation of the natural-landscape resources that calculated using the materials of multispectral space imagery is a stable indicator and criterion for land assessing in terms of their suitability for agricultural use. The results of this study can be used to provide a territorial management and planning in accordance with the goals of land use planning and sustainable development, by potential assessment and mapping a status of the natural-landscape resources.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental , Agricultura , Irã (Geográfico) , Recursos Naturais
2.
J Environ Manage ; 268: 110712, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510446

RESUMO

Keeping in view the catastrophic effects of environmental degradation, G7 countries agree to implement the policy recommendations of the famous Paris Climate Agreement (COP21) in 2015; carbon dioxide (CO2) emissions are increasing in G7 countries, which is a severe threat for the environment of the world. This study examines the effects of economic globalization on environmental degradation (CO2 emissions) for G7 countries for the period of 1996-2017. We further examine the role of financial development, agriculture value-added, and natural resources in the relationship between economic globalization and CO2 emissions. This study contributes to the existing literature by providing new empirical evidence on how economic globalization, along with financial development, agriculture value-added, and natural resources affect CO2 emissions in G7 economies. This study utilizes novel econometric techniques such as CS-ARDL for short-run and long-run results of the empirical analysis. The empirical findings show that economic globalization, financial development, and natural resources increase carbon emissions. In contrast, agriculture value-added decreases carbon emissions. This study suggests that policies designed for controlling carbon emissions should be absorbed in approximately more than one year.


Assuntos
Desenvolvimento Econômico , Recursos Naturais , Agricultura , Dióxido de Carbono , Internacionalidade
3.
PLoS Comput Biol ; 16(5): e1007820, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32365072

RESUMO

Locusts are significant agricultural pests. Under favorable environmental conditions flightless juveniles may aggregate into coherent, aligned swarms referred to as hopper bands. These bands are often observed as a propagating wave having a dense front with rapidly decreasing density in the wake. A tantalizing and common observation is that these fronts slow and steepen in the presence of green vegetation. This suggests the collective motion of the band is mediated by resource consumption. Our goal is to model and quantify this effect. We focus on the Australian plague locust, for which excellent field and experimental data is available. Exploiting the alignment of locusts in hopper bands, we concentrate solely on the density variation perpendicular to the front. We develop two models in tandem; an agent-based model that tracks the position of individuals and a partial differential equation model that describes locust density. In both these models, locust are either stationary (and feeding) or moving. Resources decrease with feeding. The rate at which locusts transition between moving and stationary (and vice versa) is enhanced (diminished) by resource abundance. This effect proves essential to the formation, shape, and speed of locust hopper bands in our models. From the biological literature we estimate ranges for the ten input parameters of our models. Sobol sensitivity analysis yields insight into how the band's collective characteristics vary with changes in the input parameters. By examining 4.4 million parameter combinations, we identify biologically consistent parameters that reproduce field observations. We thus demonstrate that resource-dependent behavior can explain the density distribution observed in locust hopper bands. This work suggests that feeding behaviors should be an intrinsic part of future modeling efforts.


Assuntos
Migração Animal/fisiologia , Comportamento Alimentar/fisiologia , Gafanhotos/fisiologia , Animais , Austrália , Comportamento Animal/fisiologia , Pradaria , Modelos Biológicos , Modelos Teóricos , Recursos Naturais/provisão & distribução , Peste , Densidade Demográfica
4.
Proc Biol Sci ; 287(1926): 20193000, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32345142

RESUMO

In many regions of the world, populations of large wildlife have been displaced by livestock, and this may change the functioning of aquatic ecosystems owing to significant differences in the quantity and quality of their dung. We developed a model for estimating loading rates of organic matter (dung) by cattle for comparison with estimated rates for hippopotamus in the Mara River, Kenya. We then conducted a replicated mesocosm experiment to measure ecosystem effects of nutrient and carbon inputs associated with dung from livestock (cattle) versus large wildlife (hippopotamus). Our loading model shows that per capita dung input by cattle is lower than for hippos, but total dung inputs by cattle constitute a significant portion of loading from large herbivores owing to the large numbers of cattle on the landscape. Cattle dung transfers higher amounts of limiting nutrients, major ions and dissolved organic carbon to aquatic ecosystems relative to hippo dung, and gross primary production and microbial biomass were higher in cattle dung treatments than in hippo dung treatments. Our results demonstrate that different forms of animal dung may influence aquatic ecosystems in fundamentally different ways when introduced into aquatic ecosystems as a terrestrially derived resource subsidy.


Assuntos
Artiodáctilos/fisiologia , Bovinos , Ecossistema , Animais , Biomassa , Herbivoria , Quênia , Gado/fisiologia , Recursos Naturais , Rios
5.
Sci Total Environ ; 720: 137631, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32325591

RESUMO

Adaptive management is the systematic acquisition and application of reliable information to improve natural resource management over time. We have employed an adaptive management framework in the control and monitoring of feral cats (Felis catus) on the Matuwa Indigenous Protected Area over the past 16 years. We used 120 Reconyx PC900 camera-traps and a rapid survey technique called the cat track activity index (TAI) to determine if aerial baiting with Eradicat® was more efficient and/or cost-effective than track baiting plus leg-hold trapping. We found that aerial baiting at $0.54 per percent decrease in cat detections is more cost-effective than track-baiting alone at $0.56 per percent decrease in cat detections. Track baiting plus leg-hold trapping, however, is more cost-effective than aerial baiting alone at reducing the number of feral cats detections at $0.39 per percent decrease in cat detections. Aerial baiting plus trapping was the most effective method of suppressing feral cats in an arid landscape with 97.7% reduction in cat detections. Trapping reduced the proportion of the population made up of adult cats from 51.5% to 38.7%, which may influence the efficacy of Eradicat®. Additionally, we found that cats were twice as likely to be detected on spinifex sandplain habitats than stony or hardpan habitats. We make several recommendations for refining feral cat management programs and future research.


Assuntos
Animais Selvagens , Animais , Gatos , Ecossistema , Recursos Naturais , Controle da População , Inquéritos e Questionários
6.
Environ Sci Pollut Res Int ; 27(16): 19251-19264, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253690

RESUMO

This study examines the impacts of economic growth, energy consumption, tourism, and natural resources on the ecological footprint in the ASEAN countries for spanning from 1995 to 2016. For this purpose, the cross-sectional dependent test, the second-generation unit root test, and the Westerlund cointegration test have been applied. The Driscoll-Kraay panel regression model has been used to check the long-run relationship among the series. Also, the Dumitrescu-Hurlin panel causality test is used to determine the paths of causal interactions. These tests help to overcome the problem of cross-sectional dependence in panel data analysis. The results showed an inverted U-shaped EKC behavior in ASEAN countries, hence a negative relation between tourism and natural resources with the ecological footprint. This implies that tourism and natural resources help to improve the environmental quality in ASEAN countries.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Estudos Transversais , Recursos Naturais
7.
Sci Total Environ ; 733: 137782, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32209235

RESUMO

Climate change is a pervasive and growing global threat to biodiversity and ecosystems. Here, we present the most up-to-date assessment of climate change impacts on biodiversity, ecosystems, and ecosystem services in the U.S. and implications for natural resource management. We draw from the 4th National Climate Assessment to summarize observed and projected changes to ecosystems and biodiversity, explore linkages to important ecosystem services, and discuss associated challenges and opportunities for natural resource management. We find that species are responding to climate change through changes in morphology and behavior, phenology, and geographic range shifts, and these changes are mediated by plastic and evolutionary responses. Responses by species and populations, combined with direct effects of climate change on ecosystems (including more extreme events), are resulting in widespread changes in productivity, species interactions, vulnerability to biological invasions, and other emergent properties. Collectively, these impacts alter the benefits and services that natural ecosystems can provide to society. Although not all impacts are negative, even positive changes can require costly societal adjustments. Natural resource managers need proactive, flexible adaptation strategies that consider historical and future outlooks to minimize costs over the long term. Many organizations are beginning to explore these approaches, but implementation is not yet prevalent or systematic across the nation.


Assuntos
Mudança Climática , Ecossistema , Biodiversidade , Conservação dos Recursos Naturais , Recursos Naturais , Estados Unidos
8.
PLoS One ; 15(2): e0228881, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023321

RESUMO

Urban environments are unique because fragments of natural or semi-natural habitat are embedded within a potentially permeable matrix of human-dominated areas, creating increased landscape and, potentially, habitat heterogeneity. In addition, urban areas can provide diet subsidies for wildlife species in the form of fruiting ornamental plants, trash, and domestic animals. Ecological opportunity in the forms of habitat and food heterogeneity are thought to be important mechanisms in maintaining individual specialization. Identifying which contexts, traits, and mechanisms determine the success or failure of individuals within an urban wildlife population could potentially provide predictions about which populations may succeed in human-dominated landscapes and which may experience local extinction. We used both scat and stable isotope analysis of whiskers to investigate the degree to which coyotes (Canis latrans) utilized anthropogenic subsidies and exhibited individual diet specialization across the urban-rural gradient in southern California. Land use surrounding scat and isotope sample locations was also evaluated to determine the effect of land cover on diet. Human food constituted a significant portion of urban coyote diet (22% of scats, 38% of diet estimated by stable isotope analysis). Domestic cats (Felis catus) and ornamental fruit and seeds were also important items in urban coyote diets. Consumption of anthropogenic items decreased with decreasing urbanization. In suburban areas, seasonality influenced the frequency of occurrence of anthropogenic subsidies with increased consumption in the dry season. The amount of altered open space (areas such as golf courses, cemeteries, and landscaped parks) nearby had a negative effect on the consumption of anthropogenic items in both urban and suburban areas. Contrary to our hypothesis, urban coyotes displayed reduced between-individual variation compared to suburban and rural coyotes. It is possible that the core urban areas of cities are so densely developed and subsidized that wildlife inhabiting these areas actually have reduced ecological opportunity. Suburban animals had the broadest isotopic niches and maintained similar individual specialization to rural coyotes. Wildlife in suburban areas still have access to relatively undisturbed natural areas while being able to take advantage of anthropogenic subsidies in neighboring residential areas. Therefore, areas with intermediate urban development may be associated with increased ecological opportunity and specialization.


Assuntos
Coiotes/fisiologia , Animais , Animais Selvagens , California , Isótopos de Carbono/análise , Cidades , Dieta , Ecossistema , Fezes/química , Feminino , Humanos , Masculino , Modelos Biológicos , Recursos Naturais , Isótopos de Nitrogênio/análise , Estações do Ano , Urbanização , Vibrissas/química
9.
Environ Sci Pollut Res Int ; 27(9): 9435-9443, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31919826

RESUMO

Statistics from the Intergovernmental Panel on Climate Change (IPCC) reveals that energy consumption remains the main root cause of anthropogenic greenhouse pollutant emissions because of economic expansion. Thus, the need to explore the determinants of environmental degradation in South Africa is pertinent for policymakers and stakeholders. The current study is conducted in a multivariate framework using an augmented carbon income function. The present study explores the theme under review with the inclusion of total natural resource rent as an additional variable to circumvent for omitted variable bias. To this end, annual time series data from 1970 to 2017 is employed for econometrics analysis. The study set off with investigation of stationarity properties with conventional unit root test in conjunction with Zivot-Andrews unit root test that accounts for single structural break. The Pesaran's bounds testing techniques traces long-run equilibrium relationship between energy (coal) consumption, pollutant emission, total natural resources rent, and economic expansion over the sampled period. Empirical test from the modified Wald test detect and validate feedback causality between energy (coal) consumption and economic expansion. This is instructive to energy stakeholders and policymakers that energy is key determinant of economic growth. Furthermore, total natural resources rent shows significant contribution to pollutant emissions in South Africa. Based on the empirical results, policy direction such as adoption of new technologies and cleaner energy sources were suggested rather than fossil fuel driven economy in South Africa.


Assuntos
Carvão Mineral , Poluentes Ambientais , Dióxido de Carbono/análise , Desenvolvimento Econômico , Recursos Naturais , África do Sul
10.
J Environ Manage ; 256: 109955, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31989981

RESUMO

Understanding how values interact is fundamental to planning the conservation and use of natural resources. However, practitioners who apply value classifications use a diversity of approaches. Does this matter? In answering this question, we propose that well-constructed classifications contribute to planning by: clarifying definitions and underlying concepts; providing a basis for assessing synergies and trade-offs; explaining some ethical constraints, including aspects of governance and power; and providing a framework for cross-cultural analysis. To test these propositions we develop complementary value classifications for end state values and principles together with supporting theory, assumptions, and criteria. The proposed classifications are then compared with alternatives including those based on 'needs', 'capabilities', and total economic value. We find that the alternatives fail against key criteria and this hampers their capacity to fulfil the four roles proposed above. Therefore, we conclude that although value classifications are important and may vary depending on purpose, they need to be well-constructed - that is, supporting theory, assumptions, and criteria should be explicit.


Assuntos
Conservação dos Recursos Naturais , Recursos Naturais , Humanos
11.
Proc Biol Sci ; 287(1919): 20192446, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31964301

RESUMO

Resource availability can powerfully influence host-parasite interactions. However, we currently lack a mechanistic framework to predict how resource fluctuations alter individual infection dynamics. We address this gap with experiments manipulating resource supply and starvation for a human parasite, Schistosoma mansoni, and its snail intermediate host to test a hypothesis derived from mechanistic energy budget theory: resource fluctuations should reduce schistosome reproduction and virulence by inhibiting parasite ingestion of host biomass. Low resource supply caused hosts to remain small, reproduce less and produce fewer human-infectious cercariae. Periodic starvation also inhibited cercarial production and prevented infection-induced castration. The periodic starvation experiment also revealed substantial differences in fit between two bioenergetic model variants, which differ in their representation of host starvation. Simulations using the best-fit parameters of the winning model suggest that schistosome performance substantially declines with resource fluctuations with periods greater than 7 days. These experiments strengthen mechanistic theory, which can be readily scaled up to the population level to understand key feedbacks between resources, host population dynamics, parasitism and control interventions. Integrating resources with other environmental drivers of disease in an explicit bioenergetic framework could ultimately yield mechanistic predictions for many disease systems.


Assuntos
Schistosoma mansoni/fisiologia , Caramujos/parasitologia , Animais , Interações Hospedeiro-Parasita , Humanos , Recursos Naturais , Parasitos
12.
Artigo em Inglês | MEDLINE | ID: mdl-31795456

RESUMO

Hulunbeir grassland, as a crucial ecological barrier and energy supply base in northwest China, suffers from a fragile ecological environment. Therefore, it is crucially important for Hulunbeir grassland to achieve the sustainable development of its social economies and ecological environments through the evaluation of its ecological security. This paper introduces the indexes of the ecological pressure index (EPI), ecological footprint diversity index (EFDI), and ecological coordination coefficient (ECC) based on the ecological footprint model. Furthermore, the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model was applied to analyze the main driving factors of the change of the ecological footprint. The results showed that: The ecological footprint (EF) per capita of Hulunbeir grassland has nearly doubled in 11 years to 11.04 ha/cap in 2016, while the ecological capacity (EC) per capita was rather low and increased slowly, leading to a continuous increase of per capita ecological deficit (ED) (from 5.7113 ha/cap to 11.0937 ha/cap). Within this, the footprint of fossil energy land and grassland contributed the most to the total EF, and forestland and cropland played the major role in EC. The EPI increased from 0.82 in 2006 to 1.25 in 2016, leading the level of ecological security to increase from level 3 (moderately safe) to level 4 (moderately risky). The indexes of the EFDI and ECC both reached a minimum in 2014 and then began to rise, indicating that Hulunbeir steppe's ecological environment, as well as its coordination with economy, was considered to be worse in 2014 but then gradually ameliorated. The STIRPAT model indicated that the main factors driving the EF increase were per capita GDP and the proportion of secondary industry, while the decrease of unit GDP energy consumption played an effective role in curbing the continuous growth of the EF. These findings not only have realistic significance in promoting the coordinated development between economy and natural resource utilization under the constraint of fragile environment, but also provide a scientific reference for similar energy-rich ecologically fragile regions.


Assuntos
Pradaria , Recursos Naturais , Medidas de Segurança , China , Conservação dos Recursos Naturais/métodos , Indústrias , Modelos Teóricos
13.
J Ethnobiol Ethnomed ; 15(1): 64, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831075

RESUMO

BACKGROUND: Due to increasing pressure on natural resources, subsistence agriculture communities in Uganda and Sub-Saharan Africa are experiencing increasingly restricted access to diminishing natural resources that are a critical requirement of their livelihoods. Previously, common-pool resources like forests and grasslands have been either gazetted for conservation or leased for agriculture, the latter in particular for large-scale sugarcane production. Satisfying the increasing consumer demand for grassland or forestry products like wild mushrooms as food or medicine, requires innovative ethno-biological and industry development strategies to improve production capacity, while easing the pressure on diminishing natural resources and averting ecosystems degradation. METHODS: This case study addresses traditional knowledge systems for artisanal mycoculture to identify cultivation practices that enhance sustainable utilization of natural resources. Multi-scalar stakeholder engagement across government and community sectors identified artisanal mushroom producers across five districts in Uganda. Focus groups and semi-structured interviews characterized artisanal production methods and identified locally used substrates for cultivation of different mushroom species. RESULTS: Artisanal practices were characterized for the cultivation of six wild saprophytic mushroom species including Volvariella speciosa (akasukusuku), two Termitomyces sp. (obunegyere and another locally unnamed species), Agaricus sp. (ensyabire) and Agrocybe sp. (emponzira), and one exotic Pleurotus sp. (oyster) that are used as food or medicine. The substrates used for each species differed according to the mushroom's mode of decomposition, those being the following: tertiary decomposers such as those growing under rotting tree stumps or logs from forestry activity like the Agrocybe sp. known as emponzira which grows in forests, thickets, or near homesteads where big logs of hardwood have been left to rot. Also pieces of firewood are chipped off whenever need arises thus providing fuel; secondary decomposers growing on naturally composted grass associated with termites like the Termitomyces sp. known as obunegyere growing in protected sites in gardens, composted cattle manure for Agaricus sp. known as ensyabire in the kraal area where cattle manure is plenty, composted maize cobs for a locally unnamed Agaricus sp. on heaped cobs placed near homesteads; and primary decomposers growing on waste sorghum from brewing the traditional alcoholic drink, muramba for Pleurotus sp. (oyster), and banana and spear grass residue from banana juice processing like the Volvariella speciosa known as akasukusuku because it is associated with the banana plantation locally known in the Luganda language as olusuku and is usually heaped under ficus trees. Management practices also varied based on mode of decomposition and other ecological requirements such as the following: zero tillage and minimal disturbance in areas where obunegyere grow, heaping banana and spear grass residues under the cool ficus trees which also keep them away from banana stump that may cause infestation with nematodes and insects. Even within the generic practices accessibility by the users is critical for example placing logs near homes where children can use them to play, they can be used as fire wood and to even get off-season mushroom as household waste water can make the mushrooms grow. CONCLUSIONS: Our description of artisanal mycoculture methods that respond to conservation and utilization pressures, demonstrates the value of addressing traditional knowledge to improve ethno-biology and mycoculture industry practice. Traditional communities engage in multiple technological and organizational innovations and practices for sustainability and in the case of mushroom production to conserve the environment and culture, ensure variety, food and nutrition security, and income. The results of this study present opportunities to preserve ecosystem quality while developing an artisanal mycoculture system. They have also identified aspects of artisanal mycoculture that most urgently require further ethno-biological study and industry development. Future research and industry development can utilize the result of this study to boost artisanal production of wild saprophytic mushrooms in Sub-Saharan countries, for food or medicinal consumption, and environment conservation. Further development of production efficiencies in context with sustainable natural resource management is recommended.


Assuntos
Agaricales/crescimento & desenvolvimento , Agricultura/métodos , Conservação dos Recursos Naturais , Ecossistema , Feminino , Humanos , Conhecimento , Masculino , Recursos Naturais , Uganda
14.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4095-4100, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872682

RESUMO

The study is aimed to effectively obtain the planting area of traditional Chinese medicine resources. The herbs used as the material for traditional Chinese medicine are mostly planted in natural environment suitable mountainous areas. The UAV low altitude remote sensing data were used as the samples and the GF-2 remote sensing images were applied for the data source to extract the planting area of Salvia miltiorrhiza and Artemisia argyi in Luoning county combined with field investigation. Remote sensing satellite data of standard processing obtain specific remote sensing data coverage. The UAV data were pre-processed to visually interpret the species and distribution of traditional Chinese medicine resources in the sample quadrat. Support vector machine( SVM) was used to classify and estimate the area of traditional Chinese medicine resources in Luoning county,confusion matrix was used to determine the accuracy of spatial distribution of traditional Chinese medicine resources. The result showed that the application of UAV of low altitude remote sensing technology and remote sensing image of satellite in the extraction of S. miltiorrhiza and other varieties planting area was feasible,it also provides a scientific reference for poverty alleviation policies of the traditional Chinese medicine Industry in local areas.Meanwhile,research on remote sensing classification of Chinese medicinal materials based on multi-source and multi-phase high-resolution remote sensing images is actively carried out to explore more effective methods for information extraction of Chinese medicinal materials.


Assuntos
Altitude , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Tecnologia de Sensoriamento Remoto , Recursos Naturais , Máquina de Vetores de Suporte
15.
PLoS One ; 14(12): e0225903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31846464

RESUMO

Communication between resource users has repeatedly been shown to be of significant importance in environmental management. The proposed causal mechanisms are numerous, ranging from the ability of users to share information to their ability to negotiate solutions to common problems and dilemmas. However, what is less known is under what conditions these potential causal mechanisms are important and if, in cases when different means other than communication were available, whether they would be more effective in accomplishing these objectives. An example of such an alternative could be that instead of (or in addition to) users being reliant on within-group communication to acquire useful information an intermediary-such as a public agency-could provide that for them. Furthermore, the different causal mechanisms making communication beneficial might not be independent, neither in respect to each other, nor in respect to other externally imposed means to facilitate better environmental management, and not in regards to different contextual factors. This study makes use of laboratory experiments in an innovative way to explore these questions and specifically test the relative importance of communication in managing complex social-ecological system characterized by common-pool resource dilemmas, ecological interdependencies, and asymmetric resource access-all characteristics being present simultaneously. We find that when resources users are confronted with such a complex challenge, the ability to communicate significantly increases individual and group performance. What is more surprising is the negative effect on overall outcomes that providing external information has on outcomes, when the users also have the ability to communicate. By analysing the content of the conversations we are able to suggest several possible explanations on how the combination of external information provisioning and user communications act to increase individual cognitive load and drives intra-group competition, leading to a significant reduction of individual and group outcomes.


Assuntos
Comunicação , Ecologia , Meio Ambiente , Recursos Naturais , Humanos , Modelos Teóricos , Pesquisa
16.
PLoS One ; 14(11): e0222630, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31721782

RESUMO

Residential land is expanding in the United States, and lawn now covers more area than the country's leading irrigated crop by area. Given that lawns are widespread across diverse climatic regions and there is rising concern about the environmental impacts associated with their management, there is a clear need to understand the geographic variation, drivers, and outcomes of common yard care practices. We hypothesized that 1) income, age, and the number of neighbors known by name will be positively associated with the odds of having irrigated, fertilized, or applied pesticides in the last year, 2) irrigation, fertilization, and pesticide application will vary quadratically with population density, with the highest odds in suburban areas, and 3) the odds of irrigating will vary by climate, but fertilization and pesticide application will not. We used multi-level models to systematically address nested spatial scales within and across six U.S. metropolitan areas-Boston, Baltimore, Miami, Minneapolis-St. Paul, Phoenix, and Los Angeles. We found significant variation in yard care practices at the household (the relationship with income was positive), urban-exurban gradient (the relationship with population density was an inverted U), and regional scales (city-to-city variation). A multi-level modeling framework was useful for discerning these scale-dependent outcomes because this approach controls for autocorrelation at multiple spatial scales. Our findings may guide policies or programs seeking to mitigate the potentially deleterious outcomes associated with water use and chemical application, by identifying the subpopulations most likely to irrigate, fertilize, and/or apply pesticides.


Assuntos
Meio Ambiente , Habitação , Recursos Naturais , Irrigação Agrícola , Cidades , Clima , Características da Família , Feminino , Fertilizantes , Humanos , Masculino , Pessoa de Meia-Idade , Praguicidas , Fatores Socioeconômicos , Estados Unidos , População Urbana
17.
PLoS One ; 14(11): e0221115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31725716

RESUMO

This study assessed the spatial and temporal variations of land cover in the agricultural areas of the Al-Hassa oasis, Kingdom of Saudi Arabia (KSA). Change detection technique was applied in order to classify variations among different surface cover aspects, during three successive stages between 1985 and 2017 (i.e., 1985 to 1999 (14 years), 1999 to 2013 (14 years), and 2013 to 2017 (4 years)), using two scenarios. During the first stage, significant urban sprawl (i.e., 3,200 ha) occurred on bare lands within the old oasis, while only 590 ha of the oasis's vegetation area was occupied by urban cover. However, the final stage revealed rapid urban development (1,270 ha by 2017) within the oasis's vegetation region, while no urban sprawl occurred on bare lands (area of 1,900 ha, same as that in 1999-2013). Vegetation cover of around 1,000 ha changed to the bare soil class, in addition to the areas that were occupied by the urban class (1,700 ha in total). The study provides quantitative information on the influence of urban development on the spatial changes in vegetation cover of the oasis, especially during recent decades.


Assuntos
Recursos Naturais , Agricultura/tendências , Conservação dos Recursos Naturais/tendências , Monitorização de Parâmetros Ecológicos/métodos , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto , Arábia Saudita , Solo , Análise Espaço-Temporal , Urbanização/tendências
18.
Commun Biol ; 2: 391, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31667365

RESUMO

Vegetation phenology is driven by environmental factors such as photoperiod, precipitation, temperature, insolation, and nutrient availability. However, across Africa, there's ambiguity about these drivers, which can lead to uncertainty in the predictions of global warming impacts on terrestrial ecosystems and their representation in dynamic vegetation models. Using satellite data, we undertook a systematic analysis of the relationship between phenological parameters and these drivers. The analysis across different regions consistently revealed photoperiod as the dominant factor controlling the onset and end of vegetation growing season. Moreover, the results suggest that not one, but a combination of drivers control phenological events. Consequently, to enhance our predictions of climate change impacts, the role of photoperiod should be incorporated into vegetation-climate and ecosystem modelling. Furthermore, it is necessary to define clearly the responses of vegetation to interactions between a consistent photoperiod cue and inter-annual variation in other drivers, especially under a changing climate.


Assuntos
Embriófitas/crescimento & desenvolvimento , Fotoperíodo , África , Agricultura , Mudança Climática , Ecossistema , Aquecimento Global , Modelos Biológicos , Recursos Naturais , Estações do Ano
19.
Mar Drugs ; 17(11)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652878

RESUMO

Intertidal zones are unique environments that are known to be ecological hot spots. In this study, sediments were collected from mudflats and decommissioned salterns on three islands in the Yellow Sea of South Korea. The diversity analysis targeted both isolates and unculturable fungi via Illumina sequencing, and the natural recovery of the abandoned salterns was assessed. The phylogeny and bioactivities of the fungal isolates were investigated. The community analysis showed that the abandoned saltern in Yongyudo has not recovered to a mudflat, while the other salterns have almost recovered. The results suggested that a period of more than 35 years may be required to return abandoned salterns to mudflats via natural restoration. Gigasporales sp. and Umbelopsis sp. were selected as the indicators of mudflats. Among the 53 isolates, 18 appeared to be candidate novel species, and 28 exhibited bioactivity. Phoma sp., Cladosporium sphaerospermum, Penicillium sp. and Pseudeurotium bakeri, and Aspergillus urmiensis showed antioxidant, tyrosinase inhibition, antifungal, and quorum-sensing inhibition activities, respectively, which has not been reported previously. This study provides reliable fungal diversity information for mudflats and abandoned salterns and shows that they are highly valuable for bioprospecting not only for novel microorganisms but also for novel bioactive compounds.


Assuntos
Fungos/genética , Água do Mar/microbiologia , Antifúngicos , Bioprospecção , Ecossistema , Meio Ambiente , Fungos/classificação , Fungos/isolamento & purificação , Recursos Naturais , Filogenia , Percepção de Quorum , República da Coreia , Tolerância ao Sal , Análise de Sequência de DNA
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