Search Results (7)

The European eel (Anguilla anguilla) undergoes significant morphological and physiological changes during its transition from the yellow to the silver stage, which are critical for its long-distance spawning migration. This study aimed to investigate these changes in European eels from the Asi River, located in Hatay, Türkiye, during their silvering process. A total of 96 eels were sampled in February 2019, and various morphometric measurements, including total length, body weight, eye dimensions and height, and pectoral fin lengths, were taken. Liver and gonad weights were also measured to assess the hepatosomatic index (HSI). The length–weight relationship for silver eels was described by the equation, W = 0.0072 × L^2.732, with silver-stage eels showing a higher growth rate compared to yellow-stage eels, which had a relationship of W = 0.0184 × L^2.397. The average total length of silver eels (431.2 ± 16.7 mm) was significantly greater than that of yellow eels (382.4 ± 11.9 mm). Additionally, pectoral fin length was significantly longer in silver eels (20.8 ± 1.1 mm) compared to yellow eels (14.8 ± 0.9 mm). The hepatosomatic index (HSI) for silver eels was also found to be higher than for yellow eels, indicating increased liver size as an adaptation for energy storage during migration. Eye height, a key indicator of silvering, showed a substantial increase during the transition, with silver-stage eels having an average eye height of 5.3 ± 0.2 mm compared to 4.2 ± 0.1 mm in yellow-stage eels. Full article

It is not unusual for a place to wait for years before being inscribed on the World Heritage List, but Sarnath—the place where the Buddha delivered his first sermon—has been on UNESCO’s “tentative list” for close to 25 years. As a sacred place for Buddhist pilgrimages, Sarnath continues to attract thousands of visitors annually and yet, remains under-developed, unlike other pilgrim towns or religious tourism destinations. This paper examines the reasons for the stunted growth of Sarnath. The findings are based on fieldwork conducted in Sarnath in 2019. The analysis of stakeholder interviews suggests several reasons for Sarnath not being able to capitalize on its religious and cultural heritage for tourism-led development. It was found that the protection of the site as an archaeological park by the Archaeological Survey of India (ASI), which has been controlling development surrounding the park as well as prohibiting the performance of any rituals, have been the key endogenous factors that have contributed to the relative under-development of a Buddhist pilgrimage economy in the town. A handful of monasteries are where Buddhist followers stay and perform their pilgrimage rituals, rendering them as enclaves. Private-sector accommodation is also limited to around 15 hotels and guesthouses. Administratively, Sarnath does not have an independent governance structure. It is governed as just one ward (an electoral constituency) by the Municipal Corporation of Varanasi and is, thus, always under the shadow of Varanasi city. Varanasi is one of the most significant Hindu sacred cities and, hence, visitors stay there for much longer durations to soak in cultural offerings, including religious ceremonies around the Ganga River; a visit to Sarnath is secondary and often limited to a half-day tour. Moreover, the archaeological park at Sarnath serves a recreational purpose as a picnic site for domestic visitors. The exogenous factors mean that the interests of Sarnath (as a Buddhist site) are hardly acknowledged by the Hindu city of Varanasi. This paper argues that the multi-layered contestations that exist at the site level, the town–ward level, and between visitors and managers have further contributed to the poor state of heritage and tourism in Sarnath. Full article

In water resources management, it is essential to have a full and complete set of hydrological parameters to create accurate models. Especially for long-term data, any shortcomings may need to be filled using the appropriate methods. Moving the recorded observed data using the drainage-area ratio (DAR) method to different points is considered one of these methods. The present study used data from six different flow observation stations in the Asi River sub-basin, known as the fertile agricultural areas in Turkey, and transferred the data to various other locations that already have existing observations. This study tested how close the values this method produced were to the actual values and investigated the question “how is missing data imputation improved by the determination of method bias coefficients?” to analyze the method’s accuracy, the streamflow drought index (SDI)—a hydrological drought index—was applied over a 12 month timescale. Contour maps were formed according to both the obtained index results by using the original data from the target station and the transferred streamflow data. As a result of this study, a severe divergence from the actual values was observed in the data directly transferred to the target stations in proportion to their area. The distance of the existing stations between each other produced a very high correlation coefficient, both in the direct transfer process and after the correction was applied. Similarly, in terms of drought index calculations, values close to 97% were seen in the original and transferred flow rates. Consequently, from the perspective of the effective management processes of water resources, the transportation of the data from basin-based observation stations corrected according to the drainage areas can be thought to positively affect the design stages and cost calculations for future water structures. Full article

Land use change is an important factor in atmospheric carbon emissions. Most of the existing studies focus on modeling the land use pattern for a certain period of time in the future and calculating and analyzing carbon emissions. However, few studies have optimized the spatial pattern of land use from the perspective of the impact of carbon emission constraints on land use structure. Therefore, in this study, the effects of land use change on carbon emissions from 1990 to 2020 were modeled using a carbon flow model for Sanmenxia, Henan, China, as an example. Then, the land use carbon emission function under the low carbon target was constructed, and the differential evolution (DE) algorithm was used to obtain the optimized land use quantity structure. Finally, the PLUS model was used to predict the optimal spatial configuration of land use patterns to minimize carbon emissions. The study produced three major results. (1) From 1990 to 2020, the structural change of land use in Sanmenxia mainly occurred between cultivated land, forest land, grassland and construction land. During this period of land use change, the carbon emissions from construction land first increased and then decreased, but despite the decrease, carbon emissions still exceeded carbon sinks, and the carbon metabolism of land use was still far from equilibrium. (2) Between 2010 and 2020, the area of cultivated land began to decrease, and the area of forest land rapidly increased, and land-use-related carbon emissions showed negative growth. This showed that the structural adjustment of energy consumption in Sanmenxia during the period decreased carbon emissions in comparison with the previous period. (3) A comparison of predicted optimized land use patterns with land use patterns in an as-is development scenario showed a decrease in construction land area of 23.05 km² in 2030 with a steady increase in forest land area and a decrease in total carbon emission of 20.43 t. The newly converted construction land in the optimized land use pattern was concentrated in the ribbon-clustered towns built during urban expansion along the Shaanling basin of the Yellow River and the Mianchi–Yima industrial development area. Full article

Soil nutrients are essential factors that reflect farmland quality. Nitrogen, phosphorus, and potassium are essential elements for plants, while silicon is considered a “quasi-essential” element. This study investigated the spatial distribution of plant nutrients in soil in a hilly region of the Pearl River Delta in China. A total of 201 soil samples were collected from farmland topsoil (0–20 cm) for the analysis of total nitrogen (TN), available phosphorus (AP), available potassium (AK), and available silicon (ASi). The coefficients of variation ranged from 47.88% to 76.91%. The NSRs of TN, AP, AK, and ASi were 0.15, 0. 07, 0.12, and 0.13, respectively. The NSRs varied from 0.02 to 0.20. All variables exhibited weak spatial dependence (R² < 0.5), except for TN (R² = 0.701). After comparing the prediction accuracy of the different methods, we used the inverse distance weighting method to analyze the spatial distribution of plant nutrients in soil. The uniform spatial distribution of AK, TN overall showed a trend of increasing from northeast to southwest, and the overall spatial distribution of AP and ASi showed that the northeast was higher than the southwest. This study provides support for the delimitation of basic farmland protection areas, the formulation of land use spatial planning, and the formulation of accurate farmland protection policies. Full article

Aquatic pollution caused by industrial effluents is an environmental issue, imposing deleterious impacts on the overall environment, specifically, on humans, by disrupting the balance of the ecosystem. Among all the industries, tanneries are considered some of the most polluting due to heavy use of toxic organic and inorganic compounds during leather processing, most of which find their way into rivers, lakes, and streams, thus exerting adverse effects on aquatic life, particularly on fish. Considering the huge concentrations of pollutants present in tannery effluents, toxicity evaluation is of prime importance. Therefore, bioassays are usually employed to assess the acute toxicity of industrial effluents and efficiency of effluent clean-up technologies as they provide a thorough response of test species to the substances present in the tested media. In the present study, the toxic effects of tannery effluent on common grass carp (Ctenopharyngodon idella) were studied for 96 h in laboratory conditions. The effluent was added at different concentrations, before and after treatment by constructed wetlands (CWs). During this period, mortality data was collected to calculate the 96 h-LC50 (lethal concentration inducing 50% mortality) and acute toxicity of C. idella. In addition to this, observations on change in morphological, physiological, and behavioural patterns were also made every 24 h. The present toxicity assay revealed that the raw tannery effluent changed the morphology, physiology, and behavioural response of fish. Moreover, fish exposure to raw/untreated effluent caused high acute toxicity and 100% mortality, due to the presence of high concentrations of salts and chromium (Cr) metal. While treatment of tannery effluent by CWs vegetated with different plants (B. mutica, L. fusca, and T. domingensis) significantly reduced its toxicity and fish mortality as well, and inoculation of salt and Cr-tolerant endophytic bacteria (Enterobacter sp. HU38, Microbacterium arborescens HU33, and Pantoea stewartii ASI11) further reduced (up to 90%) its toxicity level. Hence, the use of CWs for tannery effluent treatment can be recommended to favour public health and promote the overall safety of the environment. Full article

The paper deals with the condition assessment of water management infrastructures such as storage facilities, water mains and water distribution facilities. The objective is to develop a methodology able to provide a fast, simple assessment of present asset condition, that can also be used for predicting future conditions under different investment scenarios. The authors investigate the use of different methodologies to assess condition with focus on simple, indirect condition indices based on maintenance records, such as Infrastructure Value Index (IVI) and Asset Sustainability Index (ASI). The novelty of the approach presented is the development of a methodology that combines an asset inventory together with maintenance data, that can be integrated hierarchically, delivering an assessment of condition of elements, assets and groups of assets in a bottom-up fashion. The methodology has been applied to a group of water management infrastructures of the Segura River Basin in Spain. The main conclusion is that the proposed methodology allows to assess assets’ sustainability based upon past and current trends in operation and maintenance budgets, providing a baseline for planning future maintenance actions. Full article