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1.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(4): 384-388, 2020 May 13.
Artigo em Chinês | MEDLINE | ID: mdl-32935513

RESUMO

OBJECTIVE: To investigate the efficiency of various agroforestry systems for snail control in plateau hilly schistosomiasis-endemic areas of Yunnan Province, so as to provide insights into the construction of agroforestry schistosomiasis control projects in plateau hilly regions. METHODS: The pilot areas of snail control forests with various agroforestry systems were built in snail-breeding farmlands in Eryuan County, Yunnan Province in 2010, and the economic benefits and snail control effect were investigated in 2018. In addition, a fuzzy comprehensive evaluation model was created to screen the agroforestry system with high comprehensive benefits. RESULTS: A total of 14 types of pilot areas of snail control forests with various agroforestry systems were built. Economic benefit analysis showed that the"walnut + garlic"pattern had the best economic benefit, with annual economic benefits of 270 000 Yuan/hm2, followed by the"walnut + chili"pattern (annual economic benefits of 120 000 Yuan/hm2) and the "walnut + vegetables"pattern (annual economic benefits of 105 000 Yuan/hm2). No snails were detected in 8 types of the agroforestry systems, including the"walnut + chili"pattern, the"walnut + tobacco"pattern and the"walnut + garlic"pattern; however, there were snail found with various densities in other types of systems. Fuzzy comprehensive evaluation showed that the"walnut + garlic"pattern had the best comprehensive control effect, followed by the"walnut + chili"pattern and the"walnut + tobacco" pattern, while the pure grassland pattern showed no effect on snail control. CONCLUSIONS: The agroforestry system is a preferential approach of forestry schistosomiasis control in plateau hilly schistosomiasis-endemic areas, which not only achieves snail control effects, but also promotes economic development and ecological construction in poor hilly areas.


Assuntos
Agricultura Florestal , Controle de Pragas , Caramujos , Animais , China , Agricultura Florestal/métodos , Florestas , Humanos , Controle de Pragas/economia , Controle de Pragas/métodos , Controle de Pragas/normas , Esquistossomose/prevenção & controle , Caramujos/fisiologia
2.
PLoS One ; 15(5): e0233292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32421694

RESUMO

An important challenge for silvicultural practices is the conservation of tree diversity while fulfilling the traditional objectives of forest management, most notably timber harvesting. The purpose of this study was to compare the tree diversity before and after the application of silvicultural treatments in a temperate forest in northern Mexico. Fifteen experimental plots, each measuring 2500 m2, were established to evaluate the immediate effect of four silvicultural treatments. These treatments were identified by their levels of management: intensive (clearcut, removal 100%), semi-intensive (removal of 59-61% of basal area), conservative (removal of 29-31% of basal area), and a control group. New forest guidelines, in contrast to conventional approaches, were applied to the semi-intensive and conservative treatments based on health and diversity conditions. Basal area, canopy cover, tree and total volume were measured in each plot. The Importance Value Index, alpha diversity, and evenness were estimated before and after treatments. Eighteen species belonging to five genera and five families were found in the study area. The species with the highest ecological values were Pinus durangensis, P. teocote, Quercus sideroxyla, and Quercus convallata with IVI numbers between 13.6 and 24.5%. Alpha diversity was intermediate (Margalef: 2.9 to 3.8), while dominance and evenness were above average compared to other studies (Simpson: 0.69 to 0.77; Shannon-Wiener: 1.44 to 1.6; Pielou: 0.76 to 0.85). The species evenness index in the conservative treatment was high (Sorensen, Jaccard, quantitative Sorensen and Morisita-Horn; 88 to 99%), although abundance decreased. Overall, there were no significant differences in IVI values and diversity indicators before and after treatments, with the exception of the clearcut treatment. When associating the diversity indices with stand variables, only the Pielou's evenness index showed a significant relationship between them. We concluded that both the conservative and semi-intensive treatments did not generate significant changes in tree diversity, but the former had slightly higher alpha diversity indices. These results can provide a better insight on silvicultural practices and their effects on species composition.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Florestas , Biodiversidade , Ecossistema , México , Árvores/classificação
3.
PLoS One ; 15(4): e0230525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240191

RESUMO

Conserving forests to provide ecosystem services and biodiversity will be a key environmental challenge as society strives to adapt to climate change. The ecosystem services and biodiversity that forests provide will be influenced by the behaviors of numerous individual private landowners as they alter their use of forests in response to climate change and any future carbon pricing policies that emerge. We evaluated the impact of forest landowners' likely adaptation behaviors on potential habitat for 35 terrestrial, forest-dependent vertebrates across three U.S. Pacific states. In particular, we couple a previously estimated empirical-economic model of forest management with spatially explicit species' range and habitat associations to quantify the effects of adaptation to climate change and carbon pricing on potential habitat for our focal species (amphibians, birds and mammals) drawn from state agency lists of species of conservation concern. We show that both climate change and carbon pricing policies would likely encourage adaptation away from currently prevalent coniferous forest types, such as Douglas-fir, largely through harvest and planting decisions. This would reduce potential habitat for a majority of the focal species we studied across all three vertebrate taxa. The total anticipated habitat loss for amphibians, birds and mammals considered species of state concern would exceed total habitat gained, and the net loss in habitat per decade would accelerate over time. Carbon payments to forest landowners likely would lead to unintended localized habitat losses especially in Douglas-fir dominant forest types, and encourage more hardwoods on private forest lands. Our study highlights potential tradeoffs that could arise from pricing one ecosystem service (e.g., carbon) while leaving others (e.g., wildlife habitat) unpriced. Our study demonstrates the importance of anticipating potential changes in ecosystem services and biodiversity resulting from forest landowners' climate adaptation behavior and accounting for a broader set of environmental benefits and costs when designing policies to address climate change.


Assuntos
Adaptação Fisiológica , Biodiversidade , Carbono/metabolismo , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal/métodos , Animais , Animais Selvagens , Florestas , Propriedade , Políticas
4.
PLoS One ; 15(3): e0229835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176706

RESUMO

Quantifying the economic impacts of invasive species is an essential step in developing and prioritizing invasive species management. In particular, kudzu, Pueraria montana (Lour.) Merr. is an aggressive and non-native vine that not only causes ecological damage and reduces biodiversity, but can have multiple economic consequences such as loss of timber value and volume. Using current infestation locations in Oklahoma, southcentral USA, a Monte Carlo simulation was run to estimate the natural as well as anthropogenic spread rate of kudzu in the next five years. Simulations were supplemented with an economic impact analysis within the Impact Analysis for PLANing (IMPLAN) platform. To account for economic loss in the forest product industry, a replacement cost approach with a sensitivity analysis was conducted. Occurrence data collections revealed that current kudzu populations are already established in Oklahoma forests. The results demonstrate that by year five, total industry output could be reduced by $167.9 million, which will influence 780 jobs in the most extreme case scenario. The predicted economic loss due to kudzu expansion could act as an incentive for appropriate management practices and plans to be implemented.


Assuntos
Espécies Introduzidas/economia , Pueraria/crescimento & desenvolvimento , Agricultura Florestal/métodos , Oklahoma
5.
Sci Rep ; 10(1): 1043, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31974425

RESUMO

The incorporation of Lucanus cervus (L.) in Annex 2 of the EU Habitats Directive imposed on EU member countries the obligation to prepare protection plans and undertake adequate measures aimed at the preservation of this species. A necessary precondition for their implementation was connected with the identification of current localities of L. cervus. This paper presents the distribution of L. cervus localities in Poland, identified on the basis of a survey conducted in the areas administered by the State Forests. Habitat preferences for the selection of biotopes by stag beetles were evaluated in terms of forest-site types. This will facilitate effective protection of L. cervus by indicating potential biotopes for this species, particularly in areas with high abundance. The survey showed the presence of L. cervus in 176 localities distributed in 47 forest districts. Most of them were found in three main areas comprising forests in the areas of Zielona Góra, Wroclaw and the Swietokrzyskie Mts. They constitute large-scale refuges. In 98% of cases the development of L. cervus was associated with oaks Quercus robur and Quercus petraea. Other host plants included Fagus sylvatica and Acer pseudoplatanus. The age of trees colonised by stag beetles ranged from 70 to 248 years, 134 years on average. Lucanus cervus was most frequently found in deciduous mesic forest sites (41% of localities) and deciduous mixed mesic forest sites (24% of localities). Over 90% of recorded localities are situated in forested areas, understood to include stands, residual trees and stumps, as well as localities at forest edges and along roads in the vicinity of forests.


Assuntos
Besouros/fisiologia , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção/estatística & dados numéricos , Agricultura Florestal/métodos , Dinâmica Populacional/estatística & dados numéricos , Animais , Biodiversidade , Florestas , Geografia , Polônia
6.
Sci Total Environ ; 704: 135451, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31791782

RESUMO

Arid and semi-arid regions of central India receive scarce and episodic precipitation during the short monsoon season, and also experience substantial evaporation. Traditional and innovative water harvesting and governance practices improve water stewardship, or abate some impacts of intensive mechanised water extraction. However, significant numbers of alien trees, in particular Eucalyptus species with high water demands, populate some regions practicing progressive water stewardship. The water demands of these trees can potentially undermine efforts to achieve water security. Through interviews with community leaders in Indian villages with differing eucalyptus tree densities, water loss through evapotranspiration compared with livelihood demands was approximated. Literature review of the water demands and ecosystem services provided respectively by alien eucalypts and native, culturally valued neem trees supports assessment of the likely benefits and acceptability of a replacement programme favouring native trees. Although data limitations mean that the findings of this study are necessarily uncertain, they nonetheless illustrate the likely scale of impact, substantiating the case for alien tree management as an important contribution to water security. Alien vegetation management practices as a contribution to water security are already firmly established in South Africa, and are likely to yield equivalent benefits if translated to dryland India.


Assuntos
Agricultura Florestal/métodos , Espécies Introduzidas , Árvores , Abastecimento de Água , Clima , Ecossistema , Eucalyptus , Índia , Estações do Ano
7.
Sci Total Environ ; 698: 133761, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493576

RESUMO

In Romania, natural Norway spruce forests are spread across upper mountain slopes (1300-1800 m). They perform multiple functions, being especially recognised for their economic value. However, where planted forests extend beyond the spruce's naturally occurring areas, they are frequently exposed to deleterious environmental factors. In Romania, forest planning is based on typological studies that were carried out between 1950 and 1970, and the regulations are applied in a somewhat flexible manner. In the context of the potential threats from climate change that could amplify induced destabilising phenomena, the risks to which these forests are becoming exposed can only be mediated through flexible management and the permanent adaptation of forest planning. For this reason, the purpose of this study was to develop a strategy for adapting forest management plan guidelines, with a view to improving ecosystem stability. A Norway spruce forest was chosen from the south-eastern Carpathians, which is included in the Natura 2000 Fagaras Mountains site. The models on which we based our current stand compositions resulted from long-term monitoring and analysis of species and stand structures. Stand structure - and forest structure, in general - is key to the continuous existence of stand functions and ecosystem services. Through design decisions, we promote biodiversity and the natural, better adapted, regeneration of local provenances. We highlight the rationale behind forest management planning and its regulations, with respect to the sustainable management of Norway spruce forests, which are vulnerable to potential changes in their structure as a result of climate change. Based on our findings, we propose the adaptation of measures used in forest management planning for Norway spruce forests to include protective functions that can be applied to all man-made Norway spruce forests introduced in former beech forest regions, and mixed coniferous/beech forests, that are vulnerable to changing environmental factors.


Assuntos
Mudança Climática , Agricultura Florestal/métodos , Florestas , Picea , Noruega , Romênia
8.
An Acad Bras Cienc ; 91(4): e20190194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800707

RESUMO

The lack of accurate models for estimating residual biomass in wood harvesting operations results in underutilization of this co-product by forestry companies. Due to the lack of this information, forestry operations planning, such as chipping and transport logistics, are influenced, with a consequent increase in costs. Thereby, the aim of this study was to propose and evaluate statistical models to estimate residual biomass of Eucalyptus sp. in wood harvesting operations by means of tree variables measured from harvester processing head. Generalized linear models were composed through stepwise procedure for estimating residual biomass by tree covariates: diameter at breast height, commercial height, commercial limit diameter, and stem commercial volume, considering also their transformations and combinations. Residual biomass distributions with positive skew support the application of generalized linear model and Gamma distribution in random component, since normality assumption in traditional linear regression was a requirement not satisfied in this study. By stepwise procedure, tree variables associated to forest biomass were selected, whose linear combinations resulted in models with high statistical efficiency and accuracy. Thus, models developed in this study are innovative tools to estimate residual biomass in mechanized wood harvesting, in which can be inserted into harvester's hardware to provide real-time information.


Assuntos
Biomassa , Agricultura Florestal/métodos , Florestas , Modelos Estatísticos , Madeira
9.
PLoS One ; 14(11): e0224788, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31693689

RESUMO

Forest development is a complex phenomenon which, for the number of actors involved and the response time expressed by forests, is difficult to understand and explore. Forests in Italy, as in several areas of Europe, are experiencing intensive management and recently, an increasing impact by ungulates. The effects on forest development of these two disturbances combined are difficult to predict, and consequently to be properly managed. We used a forest landscape change model, LANDIS-II, to simulate forest development as driven by forestry practices and roe deer impact for 200 years in a mountain forest of the Italian Apennines. We found that each disturbance alters forest tree species richness, forest type abundance and distribution, and forest structure. When considered combined, the two disturbances show additive behavior, enhancing or moderating each other's effects. Forest management has a negative effect on tree species richness. We expected roe deer to have a negative effect on harvest yields, but this result was significant only for two of seven harvesting treatments. On the other hand, roe deer presence had a positive effect on tree species richness. All the simulation scenarios returned some extent of forest loss. The amount of the forest loss is lowest in the scenario without disturbances, and greatest when both disturbances are considered. However, the two disturbances combined, with the magnitude modelled in our simulations, have relatively low effects on the forest dynamics we analyzed in our study area. LANDIS-II was an effective approach for simulating combined management and ungulate driven trends of forest development, and to help understand the dynamics that lay behind it.


Assuntos
Cervos/fisiologia , Monitorização de Parâmetros Ecológicos/métodos , Agricultura Florestal/métodos , Florestas , Árvores/fisiologia , Distribuição Animal , Animais , Mudança Climática , Simulação por Computador , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Política Ambiental , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/estatística & dados numéricos , Itália , Modelos Estatísticos , Dispersão Vegetal
10.
PLoS One ; 14(9): e0222011, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31525210

RESUMO

Fire regime shifts are driven by climate and natural vegetation changes, but can be strongly affected by human land management. Yet, it is poorly known how humans have influenced fire regimes prior to active wildfire suppression. Among the last 250 years, the human contribution to the global increase in fire occurrence during the mid-19th century is especially unclear, as data sources are limited. Here, we test the extent to which forest management has driven fire regime shifts in a temperate forest landscape. We combine multiple fire proxies (macroscopic charcoal and fire-related biomarkers) derived from highly resolved lake sediments (i.e., 3-5 years per sample), and apply a new statistical approach to classify source area- and temperature-specific fire regimes (biomass burnt, fire episodes). We compare these records with independent climate and vegetation reconstructions. We find two prominent fire regime shifts during the 19th and 20th centuries, driven by an adaptive socio-ecological cycle in human forest management. Although individual fire episodes were triggered mainly by arson (as described in historical documents) during dry summers, the biomass burnt increased unintentionally during the mid-19th century due to the plantation of flammable, fast-growing pine tree monocultures needed for industrialization. State forest management reacted with active fire management and suppression during the 20th century. However, pine cover has been increasing since the 1990s and climate projections predict increasingly dry conditions, suggesting a renewed need for adaptations to reduce the increasing fire risk.


Assuntos
Fogo , Agricultura Florestal/métodos , Florestas , Sedimentos Geológicos/química , Desenvolvimento Industrial , Carvão Vegetal/análise , Lagos/química , Polônia
11.
PLoS One ; 14(9): e0222207, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513607

RESUMO

The capacity of forests to recover after disturbance, i.e., their resilience, determines their ability to persist and function over time. Many variables, natural and managerial, affect forest resilience. Thus, understanding their effects is critical for the development of sound forest conservation and management strategies, especially in the context of ongoing global environmental changes. We conducted a representative review, meta-analysis, of the forest literature in this topic (search terms "forest AND resilience"). We aimed to identify natural conditions that promote or jeopardize resilience, assess the efficacy of post-disturbance management practices on forest recovery, and evaluate forest resilience under current environmental changes. We surveyed more than 2,500 articles and selected the 156 studies (724 observations) that compared and quantified forest recovery after disturbance under different contexts. Context of recovery included: resource gradients (moisture and fertility), post-disturbance biomass reduction treatments, species richness gradients, incidence of a second disturbance, and disturbance severity. Metrics of recovery varied from individual tree growth and reproduction, to population abundance, to species richness and cover. Analyses show management practices only favored recovery through increased reproduction (seed production) and abundance of recruitment stages. Higher moisture conditions favored recovery, particularly in dry temperate regions; and in boreal forests, this positive effect increased with regional humidity. Biomass reduction treatments were only effective in increasing resilience after a drought. Early recruiting plant stages benefited from increased severity, while disturbance severity was associated with lower recovery of remaining adult trees. This quantitative review provides insight into the natural conditions and management practices under which forest resilience is enhanced and highlights conditions that could jeopardize future resilience. We also identified important knowledge gaps, such as the role of diversity in determining forest resilience and the lack of data in many regions.


Assuntos
Mudança Climática/economia , Agricultura Florestal/métodos , Árvores/crescimento & desenvolvimento , Biomassa , Secas , Florestas
12.
PLoS One ; 14(8): e0221291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31437193

RESUMO

The goal of this study was to determine if there were differences among stakeholders in the values they attribute to soil ecosystem services from plantation forests in New Zealand. Groups of forest-associated stakeholders were identified (e.g. land owners, forest owners, wood processors, and recreational forest users) and surveyed to assess their cultural background (indigenous New Zealand Maori or not) and then the relative importance they placed on 10 forest soil ecosystem services. Across all survey respondents, very high importance was placed on the ability of soils to sustain forest growth across multiple plantings/rotations (sustainable production). Interestingly, this was more highly valued than maximising short-term production. Maori placed greater importance on forest ecosystem resilience, provenance and kaitiakitanga (sensu stewardship of resources), water quality, and harvest of food and/or medicines from forests than non-Maori. These results demonstrate inherent cultural differences in valuing the range of forest ecosystem services that soils support. It is important that cultural views are understood and integrated into future soil health testing schemes to reflect the needs of all stakeholders. Ultimately, this work will help increase the sustainability of planted forest ecosystems in New Zealand, ensure the forestry sectors social licence to operate, and add value to forest products by demonstrating environmental and cultural stewardship of forest products.


Assuntos
Tecnologia Culturalmente Apropriada/ética , Agricultura Florestal/ética , Florestas , Solo/química , Participação dos Interessados/psicologia , Conservação dos Recursos Naturais , Tecnologia Culturalmente Apropriada/métodos , Grupo com Ancestrais do Continente Europeu/psicologia , Agricultura Florestal/métodos , Humanos , Povos Indígenas/psicologia , Nova Zelândia , Inquéritos e Questionários , Árvores/crescimento & desenvolvimento , Qualidade da Água
13.
PLoS One ; 14(8): e0220476, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31369652

RESUMO

Clear-cuts of forests severely affect soil structure and thus soil organic matter (SOM) and nutrient cycling dynamics therein, though with yet unknown consequences for SOM composition as well as phosphorus (P) and sulfur (S) chemical form within the soil microaggregate size fraction. To determine the effects of conventional clear-cutting on soil chemistry in a Cambisol of the Wüstebach Forest (northwestern Germany), we sampled the mineral A- and B-horizons prior to clear-cut as well as 10 and 24 month thereafter. We measured the SOM composition of soil microaggregates using pyrolysis field ionization mass spectrometry (Py-FIMS), as well as P and S chemical form and speciation using wet-chemical extractions and X-ray absorption near edge structure (XANES) spectroscopy. We found that clear-cut led to an increase of the microaggregate size fraction up to 6% due to break-down of macroaggregates and initially significantly increased total elemental concentrations (C, N, P, S) due to the introduction of slash-residues. The SOM of slash-residues consisted to a substantial amount of sterols and was generally found to be of low thermal stability and probably did not contribute to aggregate stability. Deterioration of the aggregate structure probably led to an exposure of originally inaccessible sites within aggregates to the attack by soil microorganisms and thus to an increased P and S turnover as reflected in a significantly reduction of available P proportions (4 to 7%) and a reduction of the most reduced S forms (5%). A probable increased microbial activity and contribution to SOM after clear-cut is also reflected in the significantly increasing hexose:pentose ratio by 0.25 between 10 and 24 month after clear-cut, significantly increasing the general thermal stability of SOM in the microaggregate size fraction and believed to contribute to aggregate stability. This indicated that a first deterioration of the aggregate structure after clear-cut might in the long-term be remediated with time.


Assuntos
Agricultura Florestal/métodos , Solo/química , Fósforo/análise , Enxofre/análise , Fatores de Tempo , Espectroscopia por Absorção de Raios X
15.
Sci Total Environ ; 693: 133393, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31374496

RESUMO

Black runoff occasionally flows from cutover areas of Eucalyptus plantations, polluting rivers and ponds, and resulting in fish death in severe cases. However, the occurrence patterns and environmental impacts of this black water remain unclear. Herein, we analyzed the major characteristics of black water at the occurrence sites, tested the complexation reaction of ground eucalyptus leaves with a solution of Fe3+, and determined the color and absorbance of the complex solution. The results showed that the water was dark blue, with weak acidity and strong light absorbance. The water contained a high level of dissolved organic matter content, while its chemical oxygen demand, total N, total P, NO3--N, and NH4+-N concentrations were significantly higher than those in the stream water from Eucalyptus, Pinus massoniana Lamb., and Cunninghamia lanceolata stands during the growth period. Additionally, the tannic acid concentration in the black water was 1.0 mg L-1 higher than that in the stream water from the Eucalyptus stand. The input of black water increases the concentration of tannic acid and NH4+-N, and the degradation of organic matter consumes dissolved oxygen in downstream ponds, leading to fish deaths. The presence of fresh logging residues and hot, humid weather also enable black water formation. Field investigations and simulation experiments revealed fresh Eucalyptus residues decompose rapidly under high-temperature and rainfall conditions, releasing large amounts of tannic acid, which reacts with Fe3+ to form a dark blue tannic acid­iron complex and results in black water. These results indicate that the rich Fe3+ in runoff may be a key factor in the occurrence of black water. The logging of Eucalyptus plantations during the dry season or on non-rainy days and a reduction in the logging area could prevent the occurrence of black water or mitigate the extent of its environmental hazards.


Assuntos
Eucalyptus , Peixes/fisiologia , Agricultura Florestal/métodos , Tanques/química , Água/química , Animais , China , Clima , Meio Ambiente , Qualidade da Água
16.
PLoS One ; 14(7): e0218741, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291260

RESUMO

BACKGROUND: Many studies have analysed the effect of browsing by large herbivores on tree species but far fewer studies have studied their effect on understorey shrubs and herbs. Moreover, while many studies have shown that forest features and management intensity strongly influence understorey vegetation, the influence of such variation on the effect of large-herbivore exclusion is not known. THIS STUDY: In this study, we analysed changes of species richness, Shannon diversity, evenness and cover of understorey herbs and shrubs after excluding large herbivores for seven years on 147 forest sites, differing in management intensity and forest features, in three regions of Germany (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin). Further, we studied how the effect of large-herbivore exclusion on understorey vegetation was influenced by forest management intensity and several forest features. RESULTS: As expected, exclusion of large herbivores resulted in highly variable results. Nevertheless, we found that large-herbivore exclusion significantly increased cover and Shannon diversity of shrub communities, while it did not affect herb communities. Forest management intensity did not influence the effect of large-herbivore exclusion while some forest features, most often relative conifer cover, did. In forests with high relative conifer cover, large-herbivore exclusion decreased species richness and cover of herbs and increased Shannon diversity of herbs and shrubs, while in forests with low relative conifer cover large-herbivore exclusion increased species richness and cover of herbs, and decreased Shannon diversity of herbs and shrubs. CONCLUSION: We suggest that browsing by large herbivores should be included when studying understorey shrub communities, however when studying understorey herb communities the effects of browsing are less general and depend on forest features.


Assuntos
Cadeia Alimentar , Poaceae/fisiologia , Traqueófitas/fisiologia , Árvores/fisiologia , Biodiversidade , Agricultura Florestal/métodos , Florestas , Alemanha , Herbivoria/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-31261860

RESUMO

Short-term exposure to fire smoke, especially particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5), is associated with adverse health effects. In order to quantify the impact of prescribed burning on human health, a general health impact function was used with exposure fields of PM2.5 from prescribed burning in Georgia, USA, during the burn seasons of 2015 to 2018, generated using a data fusion method. A method was developed to identify the days and areas when and where the prescribed burning had a major impact on local air quality to explore the relationship between prescribed burning and acute health effects. The results showed strong spatial and temporal variations in prescribed burning impacts. April 2018 exhibited a larger estimated daily health impact with more burned areas compared to Aprils in previous years, likely due to an extended burn season resulting from the need to burn more areas in Georgia. There were an estimated 145 emergency room (ER) visits in Georgia for asthma due to prescribed burning impacts in 2015 during the burn season, and this number increased by about 18% in 2018. Although southwestern, central, and east-central Georgia had large fire impacts on air quality, the absolute number of estimated ER asthma visits resulting from burn impacts was small in these regions compared to metropolitan areas where the population density is higher. Metro-Atlanta had the largest estimated prescribed burn-related asthma ER visits in Georgia, with an average of about 66 during the reporting years.


Assuntos
Poluentes Atmosféricos/análise , Asma/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Fogo , Agricultura Florestal/métodos , Material Particulado/análise , Poluição do Ar/análise , Monitoramento Biológico , Georgia/epidemiologia , Humanos , Estações do Ano
18.
Environ Monit Assess ; 191(8): 502, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31327078

RESUMO

The purpose of this study is to analyze the role of state ownership in forest governance in Turkey. It seeks to explore how property rights are affected by the complex, dynamic interplay of policies, economic influences, and the law. The historical development of state ownership, including its legal aspects, has been investigated in order to better understand the roots of current issues. An institutional approach has been followed. It is hypothesized that as the state exercises its property rights, it has both positive and negative effects on forest governance. This analysis confirms that state ownership may exceed its implementation capacity under the pressure of economic development objectives and that in areas where economic development is a priority, the loss of forests is inevitable. There is a need for a more adaptive approach to making policies related to property rights. The concept of the overriding public interest could be vital in achieving purposeful governance.


Assuntos
Política Ambiental , Agricultura Florestal/métodos , Florestas , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Monitoramento Ambiental , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Humanos , Propriedade , Formulação de Políticas , Turquia
19.
Environ Pollut ; 253: 636-645, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330355

RESUMO

Timber harvest has many effects on aquatic ecosystems, including changes in hydrological, biogeochemical, and ecological processes that can influence mercury (Hg) cycling. Although timber harvest's influence on aqueous Hg transformation and transport are well studied, the effects on Hg bioaccumulation are not. We evaluated Hg bioaccumulation, biomagnification, and food web structure in 10 paired catchments that were either clear-cut in their entirety, clear-cut except for an 8-m wide riparian buffer, or left unharvested. Average mercury concentrations in aquatic biota from clear-cut catchments were 50% higher than in reference catchments and 165% higher than in catchments with a riparian buffer. Mercury concentrations in aquatic invertebrates and salamanders were not correlated with aqueous THg or MeHg concentrations, but rather treatment effects appeared to correspond with differences in the utilization of terrestrial and aquatic basal resources in the stream food webs. Carbon and nitrogen isotope data suggest that a diminished shredder niche in the clear-cut catchments contributed to lower basal resource diversity compared with the reference of buffered treatments, and that elevated Hg concentrations in the clear-cut catchments reflect an increased reliance on aquatic resources in clear-cut catchments. In contrast, catchments with riparian buffers had higher basal resource diversity than the reference catchments, indicative of more balanced utilization of terrestrial and aquatic resources. Further, following timber harvest THg concentrations in riparian songbirds were elevated, suggesting an influence of timber harvest on Hg export to riparian food webs. These data, coupled with comparisons of individual feeding guilds, indicate that changes in organic matter sources and associated effects on stream food web structure are important mechanisms by which timber harvest modifies Hg bioaccumulation in headwater streams and riparian consumers.


Assuntos
Cadeia Alimentar , Agricultura Florestal/métodos , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biota , Carbono , Ecossistema , Invertebrados , Mercúrio/análise , Compostos de Metilmercúrio , Isótopos de Nitrogênio , Rios/química , Poluentes Químicos da Água/análise
20.
Environ Monit Assess ; 191(8): 495, 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31302796

RESUMO

Benefiting from current unmanned air vehicle (UAV) and remote sensing techniques, the present study aims to estimate tree count (TC), tree height (TH), and tree crown cover area (TCCA) in a young Calabrian pine stand via canopy height model (CHM). Overlay images obtained using Quadcopter were used to generate two spatial three-dimensional (3D) cloud points in two different qualities. Point clouds were processed using R program in order to produce tree data using CHM. The sensitivity of CHM-based tree data was revealed using 318 tree measurements in 32 different sampling units. Estimation and measurement values were classified based on their structure from motion (SfM) quality and cover classes, and the statistical relationships among them were analyzed. Without any classification, R2 was calculated for TC, THMean, and TCCATotal estimations and field measurements. R2 values were calculated as 0.865, 0.778, and 0.869, respectively, for SfMHighest CHM, while they were calculated as 0.863, 0.736, and 0.843, respectively, for SfMMedium CHM. In addition, sensitivity and performance ranking in different groups were determined based on root mean square error (RMSE) and mean absolute percentage error (MAPE) values. A significant difference was observed among groups in terms of quality and cover for TH, while no significant differences were observed for TCCA. Therefore, it is possible to estimate the properties of SfM CHM-based young coniferous stand. It was understood that tree density, crown shape, and branching influenced the accuracy of the present study. The developed UAV (Drone)-SfM is a promising technique for further small-scale forestry studies.


Assuntos
Monitoramento Ambiental/métodos , Agricultura Florestal/métodos , Florestas , Pinus/crescimento & desenvolvimento , Tecnologia de Sensoriamento Remoto , Árvores/crescimento & desenvolvimento , Algoritmos , Processamento de Imagem Assistida por Computador , Análise Espacial , Turquia
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