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Earth, Volume 2, Issue 3 (September 2021) – 19 articles

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Article
Estimation of Carbon Monoxide, Sulfur Oxides, Nitrogen Oxides, Volatile Organic Compounds, and Particulate Matters Emission Due to Cryptocurrency Miners’ Activity in Iran
Earth 2021, 2(3), 667-673; https://doi.org/10.3390/earth2030039 - 21 Sep 2021
Viewed by 317
Abstract
Nowadays, electricity consumption has increased worldwide due to the activity of cryptocurrency miners. Much of Iran’s electricity is generated by fossil fuel power plants. So, generating more electricity means producing more air pollutants in Iran. There is not sufficient information about the effects [...] Read more.
Nowadays, electricity consumption has increased worldwide due to the activity of cryptocurrency miners. Much of Iran’s electricity is generated by fossil fuel power plants. So, generating more electricity means producing more air pollutants in Iran. There is not sufficient information about the effects of cryptocurrency mining on Iran’s air pollution. This study aims to estimate the amount of carbon monoxide (CO), sulfur oxides (SOx), nitrogen oxides (NOx), volatile organic compounds (VOCs), and particulate matter (PM) emitted by Iran’s power plants when they generate extra electricity for cryptocurrency miners. In this study, we firstly estimated the amount of fuel used for the electricity needed for cryptocurrency miners. Then, the amounts of emitted NOx, CO, VOCs, SOx, and total PM for generation of such electricity were estimated via the guidelines of the European Environment Agency for emission inventory estimation. The results showed that an on average of 3530, 1547, 103, 11, and 35 tons of NOx, CO, VOCs, SOx, and total PM, respectively, have been emitted into the atmosphere in Iran annually. Full article
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Review
A Review of How Building Mitigates the Urban Heat Island in Indonesia and Tropical Cities
Earth 2021, 2(3), 653-666; https://doi.org/10.3390/earth2030038 - 18 Sep 2021
Viewed by 334
Abstract
A consequence of urbanization was the intensification of urban heat islands, especially in tropical cities. There have been rapid developments in infrastructure that have displaced open spaces. Meanwhile, Indonesia has a tropical climate directly affected by climate change. A high priority has been [...] Read more.
A consequence of urbanization was the intensification of urban heat islands, especially in tropical cities. There have been rapid developments in infrastructure that have displaced open spaces. Meanwhile, Indonesia has a tropical climate directly affected by climate change. A high priority has been placed on adaptation measures to address issues such as sea-level rise, increased extreme weather, and threats to ecosystems and biodiversity. There is still a lack of specific knowledge regarding tropical climate in urban areas. In this paper, the author examines how building and urban planning affect urban heat islands in the tropics. According to the review, early planning and building based on local weather data can reduce the energy consumption and minimize the UHI effect. Furthermore, a media campaign and early education should increase awareness about adaptation measures between governments and citizens. Based on the findings from this study, some recommendations are offered for future urban planning, especially for tropical climates, to reduce UHI effects. Full article
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Article
Estimating SDG Indicators in Data-Scarce Areas: The Transition to the Use of New Technologies and Multidisciplinary Studies
Earth 2021, 2(3), 635-652; https://doi.org/10.3390/earth2030037 - 11 Sep 2021
Viewed by 211
Abstract
The Sustainable Development Goals (SDGs) and their indicators provide opportunities to best combine the available knowledge and data to monitor and estimate different metrics and track their progress. The overall picture can be complex as some indicators are often interconnected (e.g., rural and/or [...] Read more.
The Sustainable Development Goals (SDGs) and their indicators provide opportunities to best combine the available knowledge and data to monitor and estimate different metrics and track their progress. The overall picture can be complex as some indicators are often interconnected (e.g., rural and/or urban development with a water body’s status). Two factors can play a crucial role in achieving the SDGs: the use of new technologies for database building and multidisciplinary studies and understanding. This study aims to explore these factors, highlight their importance and provide an example as guidance of their proper and combinative use. Ireland is used as an example of a data-scarce case with poor–slow progress, especially on the environmental SDGs. Two “non-reported” SDG indicators (lack of data) are selected and estimated in this work using freely available data (remote sensing, satellite imagery) and geospatial software for the first time in the country. The results show improvements in rural and urban development; however, this is accompanied by negative environmental consequences. A more holistic approach is needed and a broader conceptual model is presented to avoid any misleading interpretations of the study of SDGs. The transition to the modern technological and multidisciplinary evolution requires respective knowledge and understanding, strongly based on complex systems analysis. Full article
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Review
Role of Natural Capital Economics for Sustainable Management of Earth Resources
Earth 2021, 2(3), 622-634; https://doi.org/10.3390/earth2030036 - 10 Sep 2021
Viewed by 466
Abstract
Natural capital is the wealth of nations that determine their economic status. Worldwide, vulnerable people depend on natural capital for employment, salaries, wealth, and livelihoods and, in turn, this determines the developmental index of the nation to which they belong. In this short [...] Read more.
Natural capital is the wealth of nations that determine their economic status. Worldwide, vulnerable people depend on natural capital for employment, salaries, wealth, and livelihoods and, in turn, this determines the developmental index of the nation to which they belong. In this short review, we have tried to sum up the ideas and discussions over natural capital’s role in ascribing economic status to countries as well as the need for natural resource management and sustainability. This paper aimed to discuss how humanity’s prosperity is intertwined with the services that ecosystems provide, and how poor natural resource management (NRM) has adversely affected human well-being. Our preselected criteria for the review paper led us to evaluate 96 peer-reviewed publications from the SCOPUS database, which is likely the most comprehensive archive of peer-reviewed scientific literature as well as WoS, PUBMED, and Google Scholar databases. Our review revealed that the availability of ecological services is crucial for clean water and air, food and fodder, and agricultural development. We further discussed important concepts regarding sustainability, natural capital and economics, and determinants of human well-being vis-à-vis the intergenerational security of natural wealth. To ensure current and future human well-being, we conclude that an in-depth understanding of the services that ecosystems provide is necessary for the holistic management of the Earth system. Full article
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Article
A BIM-IFC Technical Solution for 3D Crowdsourced Cadastral Surveys Based on LADM
Earth 2021, 2(3), 605-621; https://doi.org/10.3390/earth2030035 - 06 Sep 2021
Viewed by 348
Abstract
In most countries, three-dimensional (3D) property units are registered utilizing two-dimensional (2D) documentation and textual description. This approach has several limitations as it is unable to represent the actual extent of complicated 3D property units in space. As traditional procedures often lead to [...] Read more.
In most countries, three-dimensional (3D) property units are registered utilizing two-dimensional (2D) documentation and textual description. This approach has several limitations as it is unable to represent the actual extent of complicated 3D property units in space. As traditional procedures often lead to increased costs and long delays in 2D cadastral surveying, a fast, cost-effective, and reliable solution is needed to cope with the remaining global cadastral surveying needs. Crowdsourcing has claimed a critical role as a reliable methodology with huge potential regarding the realization of 2D and 3D cadastral registration in both an affordable and a timely manner. Many large modern constructions are now planned and constructed based on BIM technology all over the world. The utilization of 3D digital models, such as building information models (BIMs), and the establishment of a connection with the international standard of the Land Administration Domain Model (LADM) could be a solution for the rapid integration of these units into a 3D crowdsourced cadaster with a better representation of the cadastral boundaries of these units, a detailed visualization of complex infrastructures, and an enhancement in the interoperability between different parties and organizations. In this paper, the potential linkage between the BIM, the LADM, and crowdsourcing techniques is investigated in order to provide an effective technical solution for the integration of large new constructions into 3D crowdsourced cadastral surveys. The proposed framework is tested on a building block in Athens, Greece. The potential, perspectives, and reliability of such an implementation are assessed and discussed. Full article
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Article
Use of Satellite Data for Air Pollution Modeling in Bulgaria
Earth 2021, 2(3), 586-604; https://doi.org/10.3390/earth2030034 - 02 Sep 2021
Viewed by 188
Abstract
Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter of aerodynamic diameter smaller than 10 μm (PM10). There is public and expert interest in the improvement of two operational air quality modeling systems: the Bulgarian [...] Read more.
Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter of aerodynamic diameter smaller than 10 μm (PM10). There is public and expert interest in the improvement of two operational air quality modeling systems: the Bulgarian Chemical Weather Forecast System (BgCWFS) and the Local Air Quality Management System (LAQMS) for the city of Plovdiv. The aim of the study is to investigate the effects of satellite data assimilation in BgCWFS on surface concentrations over Bulgaria (resolution 9 km), to downscale BgCWFS output to LAQMS (resolution 250 m), and to examine effects on PM10 in Plovdiv. Data from the Global Ozone Monitoring Experiment-2 (GOME-2) (MetOP satellites) for aerosols, nitrogen dioxide (NO2), and sulfur dioxide (SO2) were assimilated in BgCWFS using objective analysis. Simulation experiments with and without satellite data were conducted for a summer and a winter month. The comparison to surface observations in the country showed improvement of results when using satellite data, especially in the summer due to mineral dust events captured by satellites. The decrease in the normalized mean bias (NMB) over the two months was 43% (PM10) and 73% (SO2). The LAQMS estimated background contributions to PM10 in the city as 32%. The absolute NMB by LAQMS decreased by 38%. Full article
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Article
Natural Groundwater Recharge Response to Climate Variability and Land Cover Change Perturbations in Basins with Contrasting Climate and Geology in Tanzania
Earth 2021, 2(3), 556-585; https://doi.org/10.3390/earth2030033 - 30 Aug 2021
Viewed by 220
Abstract
The response of aquifers with contrasting climate and geology to climate and land cover change perturbations through natural groundwater recharge remains inadequately understood. In Tanzania and elsewhere in the world, studies have been conducted to assess the impact of climate change and variability, [...] Read more.
The response of aquifers with contrasting climate and geology to climate and land cover change perturbations through natural groundwater recharge remains inadequately understood. In Tanzania and elsewhere in the world, studies have been conducted to assess the impact of climate change and variability, and land use/cover changes on stream flow using different models, but similar studies on groundwater dynamics are inadequate. This study, therefore, examined the influence of land use/cover and climate dynamics on natural groundwater recharge in basins with contrasting climate and geology in Tanzania, applying the modified soil moisture balance method, coupled with the curve number (CN). The method hinges on the balance between the incoming water from precipitation and the outflow of water by evapotranspiration. The different parameters in the soil moisture balance method were computed using the Thornthwaite Water Balance software. The potential evapotranspiration (PET) was calculated using the daily maximum and minimum temperatures, utilizing two-temperature-based PET methods, Penman–Monteith (PM) and Hargreaves–Samani (HS). The rainfall data were obtained from the gauging stations under the Tanzania Meteorological Agency and some additional data were acquired from climate observatories management by water basins. The results show that there has been a quasi-stable CN in the Singida semi-arid, fractured crystalline basement aquifer (74.2 in 1997, 73.64 in 2005, and 73.87 in 2018). In the Kimbiji, humid, Neogene sedimentary aquifer, the CN has been steadily increasing (66.69 in 1997, 69.08 in 2008, and 71.42 in 2016), indicating the rapid land cover changes in the Kimbiji aquifer as compared to the Singida aquifer. For the Kimbiji humid aquifer, the PET calculated using the Penman–Monteith (PM) method for the 1996/1997, 2007/2008, and 2015/2016 hydrological years were 1156.5, 1079.5, and 1143.9 mm/year, respectively, while for the Hargreaves–Samani (HS) method, the PET was found to be 1046.1, 1138.3, and 1204.4 mm/year for the 1996/1997, 2007/2008, and 2015/2016 hydrological years, respectively. For the Singida semi-arid aquifer, the PM PET method resulted in 2083.3, 2053.6, and 1875.4 mm/year for the 1996/1997, 2004/2005, and 2017/2018 hydrological years, respectively. The HS method produced relatively lower PET values for the semi-arid area (1839.4, 1814.7, and 1710.2 mm/year) for the 1996/1997, 2004/2005, and 2017/2018 hydrological years, respectively. It was equally revealed that the recharge and aridity indices correspond with the PET calculated using two temperature-dependent methods. The decline of certain land covers (forests) and increase in others (built-up areas) have contributed to the increase in surface runoff in each study area, possibly resulting in the decreasing trend of groundwater recharge. An overestimation of the PET using the HS method in the Kimbiji humid aquifer was observed, which was relatively smaller than the overestimation of the PET using the PM method in the Singida semi-arid aquifer. Despite the difference in climate and geology, the response of the two aquifers to rainfall is similar. The combined influence of climate and land cover changes on natural groundwater recharge was observed to be prominent in the Kimbiji aquifer, while only climate variability appreciably influences natural groundwater recharge in the Singida semi-arid aquifer. El Nino and the Southern Oscillation as part of the climate variability phenomenon dwarfed the time lags between rainfall and recharge in the two basins, regardless of their difference in climate and geology. Full article
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Article
Exploring the Ever-Changing Seashore Using Geoinformatics Technology
Earth 2021, 2(3), 544-555; https://doi.org/10.3390/earth2030032 - 28 Aug 2021
Viewed by 237
Abstract
Detecting coastal morphodynamics is a crucial task for monitoring shoreline changes and coastal zone management. However, modern technology viz., Geoinformatics paves the way for long-term monitoring and observation with precise output. Therefore, this study aimed to produce explicit shoreline change maps and [...] Read more.
Detecting coastal morphodynamics is a crucial task for monitoring shoreline changes and coastal zone management. However, modern technology viz., Geoinformatics paves the way for long-term monitoring and observation with precise output. Therefore, this study aimed to produce explicit shoreline change maps and analyze the historical changes of the coastline at the east coast of the Ampara District in Sri Lanka. The histogram threshold method is used to extract data from satellite images. The time-series satellite images, acquired from 1987 to 2017, toposheet, and Google Earth historical images were compared having adjusted with the ground-truth to find the seashore changes in the study area. The histogram threshold method is used on band 5 (mid-infrared) for separating land from water pixels which means that the water pixel values were classified to one (1) and land pixel values to zero (0). The extracted shoreline vectors were associated with each other to determine the dynamics of changing shoreline of the study area. The Digital Shoreline Analysis System (DSAS) was used to find shoreline movements for each period of time. As a result, it was observed by the cross-section analysis within 100 m shoreline—seaward range along the study area—in which severe erosion has occurred northward of the Oluvil Harbor and anomalous accretion southward of the harbor because of the breakwaters constructed in the port entrance which hinder the long shore sediment transport along the study area. This situation has resulted in many ramifications to the coastal zone of the study area in socio-economic and environmental aspects in which the coastal protection mechanisms have not been well implemented to curb such issues. Full article
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Article
Examination of Susceptibility to the Deficiency of Soil Water in a Forested Agricultural Area
Earth 2021, 2(3), 532-543; https://doi.org/10.3390/earth2030031 - 28 Aug 2021
Viewed by 219
Abstract
Mountainous regions present numerous obstacles to agriculture. These include the terrain, which is associated with surface erosion, as well as surface runoff, which washes away plant nutrients and weak soil. Spatial analysis is currently used in the study of various stochastic variables, especially [...] Read more.
Mountainous regions present numerous obstacles to agriculture. These include the terrain, which is associated with surface erosion, as well as surface runoff, which washes away plant nutrients and weak soil. Spatial analysis is currently used in the study of various stochastic variables, especially those of high priority for soil water properties. Small watershed and basin-scale models were used to simulate the quantity of surface run-off, groundwater and predict the environmental impact of land use and land management practices. A new generation of the distributed hydrological models has greatly broadened simulation fields to soil and water diversified situations. The study also measured declines in slope and grain size distribution, factors impacting surface erosion and surface runoff. Multivariate statistics (canonical analysis) showed that soil moisture was most correlated both with agricultural land and forests, which is why it was used to create the model of spatial distribution. The model showed that salinity has the smallest forecast error in modeling, and thus best corresponds with the soil moisture. It is important to make a correct diagnosis of soil properties, and the degree of degradation. The assessment of the physiographic parameters of a basin will contribute to the development of proper usage and determine the quality of the water in the soil, which will be essential for forest resources and agricultural land in mountain areas exposed to surface erosion. Full article
(This article belongs to the Special Issue Terraced Landscapes as Models of Ecological Sustainability)
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Article
Development and Application of Water and Land Resources Degradation Index (WLDI)
Earth 2021, 2(3), 515-531; https://doi.org/10.3390/earth2030030 - 16 Aug 2021
Viewed by 554
Abstract
Natural resources are gradually coming under continuous and increasing pressure due to anthropogenic interventions and climate variabilities. The result of these pressures is reflected in the sustainability of natural resources. Significant scientific efforts during the recent years focus on mitigating the effects of [...] Read more.
Natural resources are gradually coming under continuous and increasing pressure due to anthropogenic interventions and climate variabilities. The result of these pressures is reflected in the sustainability of natural resources. Significant scientific efforts during the recent years focus on mitigating the effects of these pressures and on increasing the sustainability of natural resources. Hence, there is a need to develop specific indices and indicators that will reveal the areas having the highest risks. The Water and Land Resources Degradation Index (WLDI) was developed for this purpose. WLDI consists of eleven indicators and its outcome results from the spatiotemporal performance of these indicators. The WLDI is based on the Standardized Drought Vulnerability Index (SDVI) and the Environmentally Sensitive Areas Index (ESAI). The WLDI is applied for the period from October 1983 to September 1996, considering Greece as a study area. The results of the application of this index reveal the areas with the highest risks, especially in the agricultural sector, with less than the needed water quantities due to extensive periods of droughts. This index could be used by scientists, but also by policy makers, to better and more sustainably manage environmental pressures. Full article
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Article
Reconstructing the Changes in Sedimentation and Source Provenance in East African Hydropower Reservoirs: A Case Study of Nyumba ya Mungu in Tanzania
Earth 2021, 2(3), 485-514; https://doi.org/10.3390/earth2030029 - 08 Aug 2021
Viewed by 492
Abstract
This study aimed to reconstruct the sedimentation rates over time and identify the changing sources of sediment in a major hydropower reservoir in Tanzania, the Nyumba ya Mungu (NYM). Fallout 210Pb measurements were used to estimate age of sediment deposits and broad [...] Read more.
This study aimed to reconstruct the sedimentation rates over time and identify the changing sources of sediment in a major hydropower reservoir in Tanzania, the Nyumba ya Mungu (NYM). Fallout 210Pb measurements were used to estimate age of sediment deposits and broad changes in sedimentation rates were reconstructed. Sedimentation peaks were cross referenced to geochemical profiles of allogenic and autogenic elemental constituents of the sediment column to confirm a causal link. Finally, geochemical fingerprinting of the sediment cores and potential sources were compared using a Bayesian mixing model (MixSIAR) to attribute the dominant riverine and land use sources to the reservoir together with changes through recent decades. Reservoir sedimentation generally increased from 0.1 g cm−2 yr−1 in the lower sediment column to 1.7 g cm−2 yr−1 in the most recent deposits. These results correlated to changes in allogenic and autogenic tracers. The model output pointed to one of two major tributaries, the Kikuletwa River with 60.3%, as the dominant source of sediment to the entire reservoir, while the other tributary, Ruvu River, contributed approximately 39.7%. However, downcore unmixing results indicated that the latest increases in sedimentation seem to be mainly driven by an increased contribution from the Ruvu River. Cultivated land (CU) was shown to be the main land use source of riverine sediment, accounting for 38.4% and 44.6% in Kikuletwa and Ruvu rivers respectively. This study explicitly demonstrated that the integration of sediment tracing and dating tools can be used for quantifying the dominant source of sediment infilling in East African hydropower reservoirs. The results underscore the necessity for catchment-wide management plans that target the reduction of both hillslope erosion reduction and the sediment connectivity from hillslope source areas to rivers and reservoirs, which will help to maintain and enhance food, water and energy security in Eastern Africa. Full article
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Article
Assessing Reliability of Recycled Water in Wicking Beds for Sustainable Urban Agriculture
Earth 2021, 2(3), 468-484; https://doi.org/10.3390/earth2030028 - 29 Jul 2021
Viewed by 427
Abstract
Urban agriculture requires sustainable solutions to secure its water resources. A wicking bed (WB) is a simple system that could provide high yield and water use efficiency. This single trial glasshouse study compares the performance of a WB and surface irrigation (SI) system [...] Read more.
Urban agriculture requires sustainable solutions to secure its water resources. A wicking bed (WB) is a simple system that could provide high yield and water use efficiency. This single trial glasshouse study compares the performance of a WB and surface irrigation (SI) system for growing tomatoes (Solanum lycopersicum L.) using fresh (FW) and recycled water (RW). The performance of both treatments was compared when irrigating 2 days per week and for two environmental conditions (indoor and outdoor). In addition, the reliability of using FW and RW at a 7-day irrigation interval was studied for WBs alone. Results showed that the irrigation water use efficiency (kg/m3) and the yield (kg/plant) are significantly different only between WB (FW) and SI (RW) considering all conditions. The accumulation of salts and the sodium absorption ratio (SAR) were high in the surface layer of WBs compared to SI. This indicates that the use of RW affects the level of salinity and sodicity in soil, which in turn may decrease the yield. However, WBs perform similar to, if not better than, SI with FW. The WBs show the advantage of reducing the leachate of nutrients into groundwater, compared to SI systems. Further research into irrigation and nutrient management in WBs to reduce the effect of salinity at the surface is recommended to increase the efficiency of the system. Full article
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Article
Wildlife Value Orientations and Demographics in Greece
Earth 2021, 2(3), 457-467; https://doi.org/10.3390/earth2030027 - 22 Jul 2021
Viewed by 648
Abstract
Value orientations can predict attitudes and possibly behaviors. Wildlife value orientations (WVOs) are useful constructs for predicting differences in attitudes among segments of the public towards issues in the wildlife domain. We carried out face-to-face interviews with a representative sample of the Greek [...] Read more.
Value orientations can predict attitudes and possibly behaviors. Wildlife value orientations (WVOs) are useful constructs for predicting differences in attitudes among segments of the public towards issues in the wildlife domain. We carried out face-to-face interviews with a representative sample of the Greek population (n = 2392) to investigate two basic WVOs, domination and mutualism and the four WVO types that result from their combination: traditionalist (high domination, low mutualism), mutualist (high mutualism, low domination), distanced (low mutualism, low domination) and pluralist (high mutualism, high domination), and how they relate to sociodemographics. Based on basic WVOs, the Greek population was predominantly mutualism-oriented. The analysis of WVO types also revealed that mutualists were the most abundant (41.0%) followed by the distanced (31.1%). Traditionalists (17.9%) and pluralists (10.0%) occupied smaller proportions of the population. Younger individuals were more mutualist-oriented, while older individuals (>35 years old) were more traditionalist and distanced-oriented. Females were more mutualist than males, the latter being more traditionalist. Those with higher education were more mutualist and less traditionalist and distanced than those with lower education. Pet owners were more mutualist and less distanced than non-pet owners. WVO types did not vary with current residence. The produced knowledge would inform about differences in WVOs among segments of the public and would be therefore useful for implementing successful wildlife conservation and management plans. Full article
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Review
Environmental and Social Risks to Biodiversity and Ecosystem Health—A Bottom-Up, Resource-Focused Assessment Framework
Earth 2021, 2(3), 440-456; https://doi.org/10.3390/earth2030026 - 12 Jul 2021
Cited by 2 | Viewed by 671
Abstract
Risks from human intervention in the climate system are raising concerns with respect to individual species and ecosystem health and resiliency. A dominant approach uses global climate models to predict changes in climate in the coming decades and then to downscale this information [...] Read more.
Risks from human intervention in the climate system are raising concerns with respect to individual species and ecosystem health and resiliency. A dominant approach uses global climate models to predict changes in climate in the coming decades and then to downscale this information to assess impacts to plant communities, animal habitats, agricultural and urban ecosystems, and other parts of the Earth’s life system. To achieve robust assessments of the threats to these systems in this top-down, outcome vulnerability approach, however, requires skillful prediction, and representation of changes in regional and local climate processes, which has not yet been satisfactorily achieved. Moreover, threats to biodiversity and ecosystem function, such as from invasive species, are in general, not adequately included in the assessments. We discuss a complementary assessment framework that builds on a bottom-up vulnerability concept that requires the determination of the major human and natural forcings on the environment including extreme events, and the interactions between these forcings. After these forcings and interactions are identified, then the relative risks of each issue can be compared with other risks or forcings in order to adopt optimal mitigation/adaptation strategies. This framework is a more inclusive way of assessing risks, including climate variability and longer-term natural and anthropogenic-driven change, than the outcome vulnerability approach which is mainly based on multi-decadal global and regional climate model predictions. We therefore conclude that the top-down approach alone is outmoded as it is inadequate for robustly assessing risks to biodiversity and ecosystem function. In contrast the bottom-up, integrative approach is feasible and much more in line with the needs of the assessment and conservation community. A key message of our paper is to emphasize the need to consider coupled feedbacks since the Earth is a dynamically interactive system. This should be done not just in the model structure, but also in its application and subsequent analyses. We recognize that the community is moving toward that goal and we urge an accelerated pace. Full article
(This article belongs to the Special Issue Climate System Uncertainty and Biodiversity Conservation)
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Article
Impact of Wind on the Spatio-Temporal Variation in Concentration of Suspended Solids in Tonle Sap Lake, Cambodia
Earth 2021, 2(3), 424-439; https://doi.org/10.3390/earth2030025 - 06 Jul 2021
Viewed by 706
Abstract
Even though wind, water depth, and shear stress are important factors governing sediment resuspension in lakes, their actual relations to total suspended solids (TSS) distribution in natural environments have not been well elucidated. This study aims to elucidate the impact of the wind [...] Read more.
Even though wind, water depth, and shear stress are important factors governing sediment resuspension in lakes, their actual relations to total suspended solids (TSS) distribution in natural environments have not been well elucidated. This study aims to elucidate the impact of the wind on the spatio-temporal variation of TSS in Tonle Sap Lake, Cambodia, during low-water (March and June, <1 m) and high-water (September and December, 8–10 m) seasons. To this end, wind and TSS data for December 2016 and March, June, and September 2017 were collected and analyzed. For spatial interpolation of wind speed, the inverse distance weighted method was found to be better (R2 = 0.49) than the vectorized average (R2 = 0.30) and inverse of the ratio of distance (R2 = 0.31). Spatial interpolation showed that the wind speed and direction on the lake were <5 m/s and southward during the low-water season and <7 m/s and westward during the high-water season. The TSS concentration in the low-water season was higher (>50 mg/L) than that in the high-water season. The TSS concentration during the low-water season was empirically described by wind speed (W), water depth (D), and shear stress (τ_wave) with a function of W3, W3/D, and exp(W/D) or exp(τ_wave), depending on the location in the lake. The critical shear stress due to wind-induced waves at most of the places in the lake was higher than the total shear stress indicated. Sedimentation was predominant in December and June, and erosion (siltation) was dominant in March. Most of the siltation in March was dominant in the southern part of the lake. Full article
(This article belongs to the Special Issue Natural Hazards and the Sediment Cascade)
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Review
Urban Sustainability through Innovative Open Space Design. A Novel Approach to the Regeneration of Historic Open Spaces in Some Eastern European Countries and China
Earth 2021, 2(3), 405-423; https://doi.org/10.3390/earth2030024 - 05 Jul 2021
Viewed by 465
Abstract
Looking at the urban development of the past two centuries, we can conclude that engineers and architects have been dominating the field of urban design all over Europe. Architects played the most important role, which became even more significant with the increase of [...] Read more.
Looking at the urban development of the past two centuries, we can conclude that engineers and architects have been dominating the field of urban design all over Europe. Architects played the most important role, which became even more significant with the increase of urban development. Beyond the architectural approach, a greater importance had been attributed to ecological aspects of urban planning by the turn of the 20th century as, for example, the advance of the garden city movement illustrates. This article focuses on the review of crucial open-space renewal projects from two Eastern European cities and China. The case studies are used to shed light on the characteristics and historical values of contemporary open-space design, based on innovative and landscape architectural approaches and artistic solutions. The study shows that the original role of urban open spaces was significantly extended during the first decades of the 21st century. The increased needs for representation—commercial, cultural and living functions, and ecological and healthy benefits—led to a multifunctional approach in design and planning. The renewal of the historic urban open spaces is carried out under an integrated framework and a unified goal: the development-oriented heritage conservation. Based on strong economic aspects, the general tendency is clearly positive—in spite of still-existing problematic issues (for instance, the management of public transport or the status of public utilities). In the time of a growing awareness of open-space heritage, this overview tries to depict possible general principles of a long-term renewal strategy built on local identity, heritage values and social sustainability. Full article
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Article
Mapping European Rice Paddy Fields Using Yearly Sequences of Spaceborne Radar Reflectivity: A Case Study in Italy
Earth 2021, 2(3), 387-404; https://doi.org/10.3390/earth2030023 - 02 Jul 2021
Viewed by 476
Abstract
Although a vast literature exists on satellite-based mapping of rice paddy fields in Asia, where most of the global production takes place, little has been produced so far that focuses on the European context. Detection and mapping methods that work well in the [...] Read more.
Although a vast literature exists on satellite-based mapping of rice paddy fields in Asia, where most of the global production takes place, little has been produced so far that focuses on the European context. Detection and mapping methods that work well in the Asian context will not offer the same performance in Europe, where different seasonal cycles, environmental contexts, and rice varieties make distinctive features dissimilar to the Asian case. In this context, water management is a key clue; watering practices are distinctive for rice with respect to other crops, and within rice there exist diverse cultivation practices including organic and non-organic approaches. In this paper, we focus on satellite-observed water management to identify rice paddy fields cultivated with a traditional agricultural approach. Building on established research results, and guided by the output of experiments on real-world cases, a new method for analyzing time-series of Sentinel-1 data has been developed, which can identify traditional rice fields with a high degree of reliability. Typical watering practices for traditional rice cultivation leave distinctive marks on the yearly sequence of spaceborne radar reflectivity that are identified by the proposed classifier. The method is tested on a small sample of rice paddy fields, built by direct collection of ground reference information. Automated setting of parameters was sufficient to achieve accuracy values beyond 90%, and scanning of a range of values led to touch full score on an independent test set. This work is a part of a broader initiative to build space-based tools for collecting additional pieces of evidence to support food chain traceability; the whole system will consider various parameters, whose analysis procedures are still at their early stages of development. Full article
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Article
Channel Width Variation Phases of the Major Rivers of the Campania Region (Southern Italy) over 150 Years: Preliminary Results
Earth 2021, 2(3), 374-386; https://doi.org/10.3390/earth2030022 - 30 Jun 2021
Viewed by 350
Abstract
In recent decades, rivers in Southern Italy experienced remarkable channel changes. Studies on this topic are relatively recent, and yet, far from defining a morpho-evolutionary trend that is common to all rivers of this area. The types and roles of the different controlling [...] Read more.
In recent decades, rivers in Southern Italy experienced remarkable channel changes. Studies on this topic are relatively recent, and yet, far from defining a morpho-evolutionary trend that is common to all rivers of this area. The types and roles of the different controlling factors are still debated. In this study, we present preliminary results about the width channel changes of major rivers in the Campania region (Southern Italy) in the last 150 years. The aim is to provide new insights that are useful to define morpho-evolutionary trajectories at a regional scale and shed light on the roles played by controlling factors. To this aim, we carried out a GIS-aided geomorphological analysis of topographic maps and orthophotos. The results showed the existence of at least three main phases of channel width variations. Between the 1870s and 1930s (Phase 1), most of the rivers experienced widening. Between the 1930s and late 1990s (Phase 2), all of the rivers underwent dramatic narrowing at high rates. Finally, from the 1990s onwards, no dominant trend was found and variations were negligible. Land-use changes at the basin scale and rainfall changes at a decadal scale are likely the main controlling factors, while variations in human disturbances and local factors seem responsible for changes in general trends. Full article
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Article
Understanding Conceptions of ‘Nature’ for Environmental Sustainability: A Case Study in Tāmaki Makaurau Auckland, Aotearoa New Zealand
Earth 2021, 2(3), 357-373; https://doi.org/10.3390/earth2030021 - 22 Jun 2021
Viewed by 415
Abstract
Empirical research that inductively investigates lay conceptions of ‘nature’ is scarce, despite global environmental narratives around sustainability calling for humans to have harmonious relationships with ‘nature’. This paper presents inductive research that attends to the empirical knowledge gap by exploring how respondents self-reportedly [...] Read more.
Empirical research that inductively investigates lay conceptions of ‘nature’ is scarce, despite global environmental narratives around sustainability calling for humans to have harmonious relationships with ‘nature’. This paper presents inductive research that attends to the empirical knowledge gap by exploring how respondents self-reportedly conceive ‘nature’ using Auckland, New Zealand as a case study. Results suggested that conceptions of ‘nature’ within the respondent group are diverse and range across 17 themes. Most commonly, respondents conceived ‘nature’ as being something that neither humans nor human influence or activities are a part of. This finding is consistent with what has been found by previous deductive research approaches to understanding conceptions of ‘nature’. However, this research provides a deeper understanding by identifying that respondents form associations with over 60 ‘aspects’ of ‘nature’. By highlighting the complexity of ‘nature’ from a human perspective and being able to identify significant components of ‘nature’ that people associate with, this study not only provides valuable insight for environmental management in the New Zealand study site, but also has potential to support improved management of human–nature interactions that can have a more targeted impact towards achieving sustainability goals at the global scale. Full article
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