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1.
J Environ Manage ; 276: 111268, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889500

RESUMO

Biotic and abiotic drivers of seedling establishment and survival are fundamental not only for elucidating processes occurring at plant early life stages, but also for assisting species natural regeneration. Keystone, multipurpose and economically important tree species such as Afzelia africana Sm. are reportedly facing recruitment constraints, yet little is known about how abiotic and biotic factors shape the species seedling dynamics. Here, we monitored the species seedlings over one year across three seasons in West Africa savannahs to determine how conspecific and heterospecific biotic neighborhood and habitat heterogeneity correlate with initial seedling density, leaves' fungal infection and herbivory and how all these factors combined, influence the species seedling survival. Seedling densities increased with increasing conspecific adult densities, and were highest in tree savannahs and on sandy-silt soils. Leaves' fungal infection and herbivory were also positively associated with conspecific adult density, but were more abundantly observed in tree savannahs than in shrub savannahs. Seedling survival was constrained on higher slope, and negatively affected by conspecific adult density, especially in shrub savannahs. There was a strong evidence for negative density-dependence effects of conspecific adults on seedling survival, which operated through negative effects of herbivory and fungal infection. Habitat heterogeneity was also an important driver, which modulated biotic factors' effects on seedling survival: tree savannahs promote positive conspecific density-dependence of seedling fungal infection and herbivory more than shrub savannahs. Nonetheless, seedlings were more sensitive to natural enemies in shrub savannahs, suggesting increased negative conspecific density-dependence effects on seedling survival in less dense vegetation, possibly as a result of enhanced specialization of predators and pathogens on a limited set of species. The study brings important insights into the mechanisms that drive the establishment and survival of the species seedling, which should be considered in the design of management activities aiming at the conservation of this endangered species.


Assuntos
Plântula , Árvores , África Ocidental , Ecossistema , Herbivoria
2.
Pain Manag Nurs ; 20(6): 614-622, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31155279

RESUMO

PURPOSE: To reduce chemotherapy-induced neuropathy (CIN)-a significant challenge among cancer patients following chemotherapy-we explored the effects of auricular point acupressure (APA), which involves needleless, acupuncture-like stimulation on specific ear points. DESIGN/METHOD: This pilot study examined the effects of a 4-week APA intervention in the management of CIN. Descriptive analysis was used to examine the changes in study outcomes. RESULTS: Fifteen participants were enrolled. Two participants dropped out because they developed new medical conditions. Thirteen participants completed the study (87% retention rate). Study participants had more severe symptoms in their lower extremities (i.e., toes, feet, soles) than in their upper extremities (i.e., fingers, wrists, elbows). After the 4-week APA intervention, the mean percentage change scores ranged from 38% (tingling) to 49% (numbness); compared to pre-intervention, the therapeutic effects of APA were sustained at the 1-month follow-up. Function in both upper and lower extremities improved after the APA intervention (≥28%) and continued to improve at the 1-month follow-up (≥36%). CONCLUSIONS: Preliminary results from this small sample provide initial evidence of the effectiveness of APA on CIN. Future studies should confirm these results using a larger sample, a comparative sham control, and an examination of the underlying physiological mechanisms of the anti-CIN effects of APA. CLINICAL IMPLICATIONS: APA may provide an inexpensive and effective complementary approach for the self-management of CIN. Once the seeds have been taped to the patient's ear by the provider, patients are empowered to self-manage their CIN in their own environment.


Assuntos
Acupressão/normas , Antineoplásicos/efeitos adversos , Orelha/inervação , Neuralgia/terapia , Avaliação de Resultados em Cuidados de Saúde/normas , Autorrelato , Acupressão/métodos , Adulto , Antineoplásicos/uso terapêutico , Tratamento Farmacológico/métodos , Orelha/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Neuralgia/psicologia , Inquéritos e Questionários , Resultado do Tratamento
3.
Pain Manag Nurs ; 20(6): 623-632, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31204029

RESUMO

PURPOSE: To manage chemotherapy-induced neuropathy (CIN), this paper explores reliable and valid objectives measures to evaluate the treatment effects of auricular point acupressure (APA). DESIGN/METHOD: This study was a repeated-measures one-group design. Participants received four weeks of APA to manage their CIN. The laboratory-assessed and objective outcomes included quantitative sensory testing, grip and pinch strength, and inflammatory biomarkers. Wilcoxon matched pairs signed-rank tests were conducted to determine change scores of outcomes at pre- vs. post- and pre- vs. 1-month follow-up. Spearman's rho correlation coefficient was used to examine the linear association of score changes of all objective study outcomes. RESULTS: Comparing pre-and-post APA, (1) the mean score of the monofilament for all lower extremity sites tested decreased after APA, indicating sensory improvement; (2) the suprathreshold pinprick stimuli mean scores on the upper extremities increased, except the scores from the index finger and thumb; (3) the pain tolerance of thumb and trapezius areas increased; (4) decreasing IL1ß (p = .05), IFNγ (p = .02), IL-2 (p = .03), IL-6 (p = .05), IL-10 (p = .05), and IP10/CXCL10 (p = .04) were observed pre-post APA. Conditional pain modulation was significantly (p< .05) associated with pain intensity (r = 0.55), tingling (r = 0.59); and IL1ß concentration (r = 0.53) pre-post APA. The sustained effects of 4-week APA were observed at the 1-month follow-up. CONCLUSIONS: Our study findings demonstrated the promising effectiveness of APA in the management of CIN, and these treatment effects can be assessed using reliable and valid objective measures. CLINICAL IMPLICATIONS: If the efficacy of APA to manage CIN is confirmed in a larger sample, APA has the potential to be a scalable treatment for CIN because it is a reproducible, standardized, and easy-to-perform intervention.


Assuntos
Acupressão/normas , Antineoplásicos/efeitos adversos , Orelha/inervação , Neuralgia/terapia , Acupressão/métodos , Acupressão/estatística & dados numéricos , Adulto , Antineoplásicos/uso terapêutico , Tratamento Farmacológico/métodos , Orelha/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/psicologia , Autorrelato , Inquéritos e Questionários , Resultado do Tratamento
4.
Oecologia ; 187(3): 783-795, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29691648

RESUMO

Forest stratification plays a crucial role in light interception and plant photosynthetic activities. However, despite the increased number of studies on biodiversity-ecosystem function, we still lack information on how stratification in tropical forests modulates biodiversity effects. Moreover, there is less investigation and argument on the role of species and functional traits in forest layers. Here, we analysed from a perspective of forest layer (sub-canopy, canopy and emergent species layers), the relationship between diversity and aboveground biomass (AGB), focusing on functional diversity and dominance, and underlying mechanisms such as niche complementarity and selection. The sub-canopy layer had the highest species richness and diversity, while the emergent layer had the highest AGB. Species richness-AGB relationship was positive for each forest layer, but stronger for sub-canopy layer than for canopy and emergent layers. Total AGB was strongly correlated with functional diversity, leaf and wood traits of species in the sub-canopy and canopy layers. This suggests that sub-canopy and canopy species are major drivers of stand diversity-AGB relationship, and that resource filtering by canopy or emergent trees may not reduce the strength of diversity-AGB relationship in the sub-canopy layer. We argue that complementary resource use by sub-canopy species that supports niche complementarity, is a key mechanism driving AGB in natural forests. Selection effects are most evident in emergent species and niche complementarity effects for sub-canopy and canopy species, supporting arguments that AGB is affected by sub-canopy species' efficient use of limited resources despite competition from emergent species.


Assuntos
Ecossistema , Florestas , Biodiversidade , Biomassa , Árvores
5.
J Environ Manage ; 189: 160-167, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28038411

RESUMO

Honey bees play a vital role in the pollination of flowers in many agricultural systems, while providing honey through well managed beekeeping activities. Managed honey bees rely on the provision of pollen and nectar for their survival and productivity. Using data from field plot inventories in natural mistbelt forests, we (1) assessed the diversity and relative importance of honey bee plants, (2) explored the temporal availability of honey bee forage (nectar and pollen resources), and (3) elucidated how plant diversity (bee plant richness and overall plant richness) influenced the amount of forage available (production). A forage value index was defined on the basis of species-specific nectar and pollen values, and expected flowering period. Up to 50% of the overall woody plant richness were found to be honey bee plant species, with varying flowering period. As expected, bee plant richness increased with overall plant richness. Interestingly, bee plants' flowering period was spread widely over a year, although the highest potential of forage supply was observed during the last quarter. We also found that only few honey bee plant species contributed 90 percent of the available forage. Surprisingly, overall plant richness did not significantly influence the bee forage value. Rather, bee plant species richness showed significant and greater effect. The results of this study suggest that mistbelt forests can contribute to increase the spatial and temporal availability of diverse floral resources for managed honey bees. Conservation efforts must be specifically oriented towards honey bee plant species in mistbelt forests to preserve and enhance their potential to help maintain honey bee colonies. The implications for forest management, beekeeping activities and pollination-based agriculture were discussed.


Assuntos
Abelhas , Flores , Florestas , Agricultura , Animais , Biodiversidade , Pólen , Polinização , África do Sul
6.
Sci Rep ; 13(1): 11509, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460693

RESUMO

Climatic and edaphic effects are increasingly being discussed in the context of biodiversity-ecosystem functioning. Here we use data from West African semi-arid tree savannas and contrasting climatic conditions (lower vs. higher mean annual precipitation-MAP and mean annual temperature-MAT) to (1) determine how climate modulates the effects of species richness on aboveground carbon (AGC); (2) explore how species richness and AGC relate with soil variables in these contrasting climatic conditions; and (3) assess how climate and soil influence directly, and/or indirectly AGC through species richness and stand structural attributes such as tree density and size variation. We find that greater species richness is generally associated with higher AGC, but more strongly in areas with higher MAP, which also have greater stem density. There is a climate-related influence of soils on AGC, which decreases from lower to higher MAP conditions. Variance partitioning analyses and structural equation modelling show that, across all sites, MAP, relative to soils, has smaller effect on AGC, mediated by stand structural attributes whereas soil texture and fertility explain 14% of variations in AGC and influence AGC directly and indirectly via species richness and stand structural attributes. Our results highlight coordinated effects of climate and soils on AGC, which operated primarily via the mediation role of species diversity and stand structures.


Assuntos
Florestas , Árvores , Ecossistema , Solo , Carbono , Pradaria , Biomassa , Biodiversidade
7.
Plant Environ Interact ; 4(6): 342-352, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38089846

RESUMO

Traditional grazing management practices are central to rangeland productivity and biodiversity. However, the degradation of rangelands and loss of ecosystem services have raised concerns about the future of pastoralism as a form of land use. It is imperative to understand how these practices influence vegetation attributes, e.g., herbaceous species diversity and composition, growth forms (grass, forbs), life form (annuals, perennials), tree metrics (density, canopy cover, and biomass). This study evaluates vegetation shifts under three grazing management practices-enclosures, open grazing, and browsing lands-in the Somali pastoral ecosystem of Ethiopia. Enclosures exhibited the highest diversity in herbaceous species, with open grazing lands favoring forbs and annuals. Distinct compositional shifts in herbaceous species were observed across regimes, especially in grass and annuals. Enclosures had three times higher herbage biomass of open grazing and double that of browsing management practice. Conversely, browsing management practices presented optimal wood biomass, density, and canopy cover. The results highlight that a transition to combined enclosure and browsing practices can elevate plant production and diversity, benefiting the Somali rangeland economy. Consequently, dryland restoration should incorporate indigenous knowledge to ensure future rangeland sustainability and biodiversity preservation.

8.
Sci Rep ; 13(1): 22210, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097646

RESUMO

Despite the importance of agroforestry parkland systems for ecosystem and livelihood benefits, evidence on determinants of carbon storage in parklands remains scarce. Here, we assessed the direct and indirect influence of human management (selective harvesting of trees), abiotic factors (climate, topography, and soil) and multiple attributes of species diversity (taxonomic, functional, and structural) on aboveground carbon (AGC) stocks in 51 parklands in drylands of Benin. We used linear mixed-effects regressions and structural equation modeling to test the relative effects of these predictors on AGC stocks. We found that structural diversity (tree size diversity, HDBH) had the strongest (effect size ß = 0.59, R2 = 54%) relationship with AGC stocks, followed by community-weighted mean of maximum height (CWMMAXH). Taxonomic diversity had no significant direct relationship with AGC stocks but influenced the latter indirectly through its negative effect on CWMMAXH, reflecting the impact of species selection by farmers. Elevation and soil total organic carbon content positively influenced AGC stocks both directly and indirectly via HDBH. No significant association was found between AGC stocks and tree harvesting factor. Our results suggest the mass ratio, niche complementarity and environmental favorability as underlying mechanisms of AGC storage in the parklands. Our findings also highlight the potential role of human-driven filtering of local species pool in regulating the effect of biodiversity on AGC storage in the parklands. We conclude that the promotion of AGC stocks in parklands is dependent on protecting tree regeneration in addition to enhancing tree size diversity and managing tall-stature trees.


Assuntos
Ecossistema , Árvores , Humanos , Árvores/fisiologia , Florestas , Carbono , Biodiversidade , Solo , Biomassa
9.
Sci Total Environ ; 782: 146821, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33839676

RESUMO

The establishment of grazing exclosures is widely practiced to restore degraded agricultural lands and forests. Here, we evaluated the potential of grazing exclosures to contribute to the "4 per 1000" initiative by analyzing the changes in soil organic carbon (SOC) stocks and sequestration (SCS) rates after their establishment on degraded communal grazing lands in Tigray region of Ethiopia. We selected grazing areas that were excluded from grazing for 5 to 24 years across the three agroecological zones of the region and used adjacent open grazing lands (OGLs) as control. Soil samples were collected from two depths (0-15 cm and 15-30 cm) and SOC and aboveground C stocks were quantified in both exclosures and OGLs. The mean SOC stock and SCS rate in exclosures (0-30 cm) were 31 Mg C ha-1 and 3 Mg C ha-1 year-1, which were respectively 166% and 12% higher than that in the OGLs, indicating a positive restoration effect of exclosures on SOC storage. With increasing exclosure age, SOC stock and SCS rate increased in the exclosures but decreased in the OGLs. Higher SOC stock and SCS rate were recorded in 0-15 cm than in 15-30 cm. The relative (i.e., to the SOC stock in OGLs) rates of increase in SOC stocks (70-189‰ year-1) were higher than the 4‰ year-1 and were initially high due to low initial SOC stock but declined over time after a maximum value of SOC stock is reached. Factors such as aboveground biomass, altitude, clay content and precipitation promoted SOC storage in exclosures. Our study highlights the high potential of exclosures for restoring SOC in the 0-30 cm soil depth at a rate greater than the 4‰ value. We argue that practices such as grazing exclosure can be promoted to achieve the climate change mitigation target of the "4‰" initiative.

10.
Sci Total Environ ; 776: 145838, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33639469

RESUMO

Grazing exclosures have been promoted as an effective and low-cost land management strategy to recover vegetation and associated functions in degraded landscapes in the tropics. While grazing exclosures can be important reservoirs of biodiversity and carbon, their potential in playing a dual role of conservation of biodiversity and mitigation of climate change effects is not yet established. To address this gap, we assessed the effect of diversity on aboveground carbon (AGC) and the relative importance of the driving biotic (functional diversity, functional composition and structural diversity) and abiotic (climate, topography and soil) mechanisms. We used a dataset from 133 inventory plots across three altitudinal zones, i.e., highland, midland and lowland, in northern Ethiopia, which allowed local- (within altitudinal zone) and broad- (across altitudinal zones) environmental scale analysis of diversity-AGC relationships. We found that species richness-AGC relationship shifted from neutral in highlands to positive in mid- and lowlands as well as across the altitudinal zones. Structural diversity was consistently the strongest mediator of the positive effects of species richness on AGC within and across altitudinal zones, whereas functional composition linked species richness to AGC at the broad environmental scale only. Abiotic factors had direct and indirect effects via biotic factors on AGC, but their relative importance varied with altitudinal zones. Our results indicate that the effect of species diversity on AGC was altitude-dependent and operated more strongly through structural diversity (representing niche complementarity effect) than functional composition (representing selection effect). Our study suggests that maintaining high structural diversity and managing functionally important species while promoting favourable climatic and soil conditions can enhance carbon storage in grazing exclosures.

11.
Ecol Evol ; 6(20): 7546-7557, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-28725419

RESUMO

The relationship between biodiversity and ecosystem function has increasingly been debated as the cornerstone of the processes behind ecosystem services delivery. Experimental and natural field-based studies have come up with nonconsistent patterns of biodiversity-ecosystem function, supporting either niche complementarity or selection effects hypothesis. Here, we used aboveground carbon (AGC) storage as proxy for ecosystem function in a South African mistbelt forest, and analyzed its relationship with species diversity, through functional diversity and functional dominance. We hypothesized that (1) diversity influences AGC through functional diversity and functional dominance effects; and (2) effects of diversity on AGC would be greater for functional dominance than for functional diversity. Community weight mean (CWM) of functional traits (wood density, specific leaf area, and maximum plant height) were calculated to assess functional dominance (selection effects). As for functional diversity (complementarity effects), multitrait functional diversity indices were computed. The first hypothesis was tested using structural equation modeling. For the second hypothesis, effects of environmental variables such as slope and altitude were tested first, and separate linear mixed-effects models were fitted afterward for functional diversity, functional dominance, and both. Results showed that AGC varied significantly along the slope gradient, with lower values at steeper sites. Species diversity (richness) had positive relationship with AGC, even when slope effects were considered. As predicted, diversity effects on AGC were mediated through functional diversity and functional dominance, suggesting that both the niche complementarity and the selection effects are not exclusively affecting carbon storage. However, the effects were greater for functional diversity than for functional dominance. Furthermore, functional dominance effects were strongly transmitted by CWM of maximum plant height, reflecting the importance of forest vertical stratification for diversity-carbon relationship. We therefore argue for stronger complementary effects that would be induced also by complementary light-use efficiency of tree and species growing in the understory layer.

12.
Complement Ther Clin Pract ; 21(2): 124-30, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25682522

RESUMO

Healthcare providers may experience a high level of stress, fatigue, and anxiety originating from different factors. Mind-body therapies, which include many interventions, have been proposed to alleviate these conditions. These interventions have been reported to decrease the level of stress, and the negative outcomes associated with these factors: high burnout rate, and poor quality of care for patients. Although research validating the effectiveness of healthcare providers' use of mind-body therapies to care for themselves is emerging, there is little focus on barriers and facilitators that healthcare providers encounter with these mind-body practices, thereby questioning the feasibility and sustainability of these interventions. As such, this systematic review examined the barriers preventing healthcare providers from using mind-body interventions to care for themselves and ways that it has been facilitated. Overall, 12 studies addressed the research question with a limited focus on the facilitators and barriers of the use of mind-body therapies.


Assuntos
Pessoal de Saúde , Terapias Mente-Corpo , Ansiedade/psicologia , Ansiedade/terapia , Fadiga/psicologia , Fadiga/terapia , Humanos , Resiliência Psicológica , Autocuidado , Estresse Psicológico
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