Environments, Volume 6, Issue 9 (September 2019) – 9 articles

Forest landowner activities change over the lifespan of the forest and ownership cycle. Patterns of change emerge which suggest the evolving nature of forest landownership and Non-industrial Private Forest (NIPF) landowners’ interest in their land. The objective of this study was to examine trends in NIPF landowners’ distribution of forestry expenses in their management activities over time. First, 2010 Mississippi NIPF landowners were randomly selected from a property tax roll list. Our analysis compared study results of Arano et al. (2002) with a 2016 survey that was conducted by the authors of this paper. Both studies drew on assessments of timber management expenditures that were conducted on behalf of a state government department of revenue to determine ad valorem taxes for forest land. As such, both studies contained similar survey questions with 12 forestry-related activities grouped into four major categories: (1) Fees for Professional Services (e.g., consulting foresters, surveyors), (2) Timber Management Expenditures (e.g., site preparation, planting), (3) Other Management Expenditures (e.g., road construction), and (4) Property Taxes. Like the 2002 article, results here are presented as descriptive statistics. In both survey cycles, Timber Management Expenditures represented the largest component of annual expenditures in both the 1990s and 2015. The largest decrease in reported expenditures occurred for Other Management Expenditures. By broadly describing differences in expenditures over time, this study provides insights into the involvement of NIPF landowners in management activities on forest land such as reforestation after final harvest, thinning, and timber stand improvement, which can impact forest products’ supply over time. Full article

The organic water contaminant, methyl orange contaminant (M.O), has shown a hazardous increase in our water systems over the past few years due to its increasing demand in industrial processes. The photocatalytic degradation of the commercial dye was studied through the application of modified TiO₂ composite catalysts in aqueous solution under artificial irradiation. The improvement of photocatalytic activity is strongly affected by the various functional groups emerging in the organic substances. In this work, the effect of both silver-iron and silver-iron-reduced graphene oxide-modified titanium dioxide towards M.O remediation as a cost-effective photocatalyst was investigated. We confirmed that the novel AgFe functionalized TiO₂ catalyst (AgFe-TiO₂) showed more superior remediation activity than the reduced graphene oxide (rGO)-modified TiO₂ due to the decreased band gap from 3.02 eV–2.5 eV with increased photocatalysis. Based on the spectroscopic and microscopic results, the enhanced photocatalytic degradation of M.O dye was induced by its enhanced surface area, electron diffusion, and the reduction of photo-generated electron-hole pairs’ recombination. Full article

Planning urban expansion under the interconnected Sustainable Development Goals requires a systemic analysis of its environmental impacts. The benefits of integrating the widely used system analysis tool life cycle assessment (LCA) into the planning process tool environmental impact assessment (EIA) are described in the literature. However, not many applications of such an integration have been conducted. The aim of this study is to refine the framework for integrating LCA into the process of EIA and to apply this framework to an example of urban expansion: Masdar City in Abu Dhabi. The integrated framework builds on the complementarity between the scope and assessment steps of the tools and assesses the impacts for the areas of protection: human health, ecosystem, and resources. The framework is then applied to the vehicles, buildings, and infrastructure in the city’s first development phase (DP1). Major environmental stressors include the loss of existing desert ecosystem and the utilization of non-renewable sources of energy at various development stages of DP1. Substituting natural gas-based electricity with solar power could potentially save 46% of current carbon emissions. To mitigate the land transformation impacts, construction of “close-to-nature” artificial habitats, and increased use of low-carbon fuels is suggested. Full article

Throughout the world, areas have been reserved for their exceptional environmental values, such as high biodiversity. Financial, political and community support for these protected areas is often dependent on visitation by nature-based tourists. This visitation inevitably creates environmental impacts, such as the construction and maintenance of roads, tracks and trails; trampling of vegetation and erosion of soils; and propagation of disturbance of resilient species, such as weeds. This creates tension between the conservation of environmental values and visitation. This review examines some of the main features of environmental impacts by nature-based tourists through a discussion of observational and manipulative studies. It explores the disturbance context and unravels the management implications of detecting impacts and understanding their causes. Regulation of access to visitor areas is a typical management response, qualified by the mode of access (e.g., vehicular, ambulatory). Managing access and associated impacts are reviewed in relation to roads, tracks and trails; wildlife viewing; and accommodations. Responses to visitor impacts, such as environmental education and sustainable tour experiences are explored. The review concludes with ten recommendations for further research in order to better resolve the tension between nature conservation and nature-based tourism. Full article

Integrated coastal zone management proposes nature-based mitigation strategies based on the replacement of artificial coastal stabilization and protection structures with dunes stabilized with plant species. These psammophytes stabilize sands and act as supporters, increasing dunes’ ability to reduce storm damages and effectively minimize erosion with minimal negative impacts to natural ecosystems. That is why searching for native salt-tolerant plants with extensive root systems and studying their capacity for erosion and flooding control is fundamental to the practice of ecologically-sound ecosystem services. The aim of the present study is to define the effects of flooding stress on a number of wheatgrass (Thinopyrum ponticum) plant life aspects (survival ability, viability, and growth response) in order to determine wheatgrass’s capacity as dune stabilizer. Conducted experiments established that T. ponticum was very tolerant to immersion impact and salt and oxygen deficiency stress, and its rhizomes were able to regenerate after 30 days in seawater. The temporal expression of its survival is presented as critical decomposition time (CDT) by linking the maximum duration of floods along the Bulgarian Black Sea Coast and the resilience of tall wheatgrass in flooding simulations. A statistical analysis of the experimental data demonstrated that immersion in sea water increases rhizome viability, biomass, and allocation to root biomass, whereas other factors, such as the duration of immersion, salinity, and temperatures of sea water have no significant effect. According to flood resilience and growth response to sea water submergence, T. ponticum demonstrated high potential to be a dune stabilizer. Full article

The relative tolerance of four diatoms (Nitzschia palea, Pinnularia mesolepta, Mayamaea atomus, and Gomphonema truncatum) to Cd was evaluated, including their proneness to deformities, and the severity of the abnormalities in relation to Cd concentration. The indirect effect of Cd on photosynthetic capacities was assessed during a short time exposure experiment using a dose-response approach to evaluate the relative tolerance of the four diatom species. The EC₂₅ were 9 (3, 23), 606 (348, 926), 1179 (1015, 1349) and 2394 (1890, 2896) µg/L for P. mesolepta, G. truncatum, N. palea, and M. atomus respectively. P. mesolepta was by far the most Cd sensitive species while M. atomus was the most tolerant. In addition, diatoms were exposed to a single concentration of Cd comparable to a heavily contaminated environment for a longer duration to evaluate the effect of Cd on growth kinetics and the deformities induced. N. palea, P. mesolepta, and M. atomus were able to grow when cultivated with Cd while G. truncatum was not. Cadmium strongly affected the effective quantum yield in G. truncatum (4.8 ± 5.9% of the control) and P. mesolepta cultures (29.2 ± 6.9% of the control). The effects were moderate for N. palea (88.3 ± 0.7% of the control) and no impact was observed for M. atomus. The results from the two approaches were in accordance since they identified N. palea and M. atomus as the two most tolerant species to Cd, while P. mesolepta and G. truncatum were the most sensitive. The microscopy analyses revealed that P. mesolepta was more impacted by Cd than N. palea and M. atomus considering both the quantity of abnormal cells and the severity of the deformities. Overall, this research shows that not all deformities can be considered equal for a water quality bio-assessment. The work highlights a need to take into account metal-tolerance/sensitivity of the species and the severity of the deformities. Full article

This work aims to investigate possible interferences due to the presence of sodium carbonate on the photodegradation of the reactive Black 5 azoic dye, both in systems containing only titanium oxide and those containing titanium oxide and hydrogen peroxide. The role of hydrogen peroxide is explicitly treated. Sodium carbonate, in fact, is often present in the wastewater of textile industries as it is used in the fiber dyeing phases. The use of TiO₂ nanoparticles is emphasized, and the possible danger is underlined. Each system was subjected to ultraviolet irradiation (UV) by varying the exposure time. After the photodegrading tests, the resulting solutions were analyzed by UV-vis spectrophotometry and High-Resolution Nuclear Magnetic Resonance to measure the residual concentrations of dye. The dye degradation curves and reaction rates for different UV exposure times were obtained and discussed as a function of the used additives. All the data are repeated three times, and they differ only by a maximum of 5%. The results indicated a reduction of about 50% of the initial concentration of Reactive Black 5 after 30 min under optimal experimental conditions. The NMR analysis indicated the formation of a series of aromatic structures that were generated by the UV-induced photochemical fragmentation of the original molecule. Full article

High concentrations of negative air ions (NAIs) and low concentrations of positive air ions (PAI), along with a low monopole coefficient (PAI/NAI), are likely to provide physiological and psychological benefits to the humans. A water body produces NAIs through the Lenard effect. This concept can be applied in designing garden waterscapes in residential buildings to provide fresh and healthy air for urban residents. In this study, we conducted several experiments to assess the effectiveness of different waterscape designs in producing air ions. The results revealed that increasing waterfall tiers, slopes, impact points, widths, and heights increased the NAI concentrations and reduced the values of monopole coefficients, thus providing health benefits to humans. In particular, increasing waterfall tiers and slopes increased the NAI concentrations most substantially. Moreover, we established a composite waterscape and determined that it produced fewer NAIs along with a less favorable monopole coefficient compared with the data observed at the experimentally adjusted tiers and slopes. Therefore, we suggest that simple waterscapes with multiple waterfall tiers or steep waterfall slopes should be favored over complex waterscapes. Such simple designs can help construct a garden that provides health benefits. Full article

With growing tourism in natural areas, monitoring recreational impacts is becoming increasingly important. This paper aims to evaluate how different trampling intensities affect some common Icelandic plant communities by using digital photographs to analyze and quantify vegetation in experimental plots and to monitor vegetation recovery rates over a consecutive three-year period. Additionally, it seeks to evaluate the use of image analysis for monitoring recreational impact in natural areas. Experimental trampling was conducted in two different sites representing the lowlands and the highlands in 2014, and the experimental plots were revisited in 2015, 2016, and 2017. The results show that moss has the highest sensitivity to trampling, and furthermore has a slow recovery rate. Moss-heaths in the highlands also show higher sensitivity and slower recovery rates than moss-heaths in the lowlands, and grasslands show the highest resistance to trampling. Both methods tested, i.e., Green Chromatic Coordinate (GCC) and Maximum Likelihood Classification (MLC), showed significant correlation with the trampling impact. Using image analysis to quantify the status and define limits of use will likely be a valuable and vital element in managing recreational areas. Unmanned aerial vehicles (UAVs) will add a robust way to collect photographic data that can be processed into vegetation parameters to monitor recreational impacts in natural areas. Full article