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The Sundarbans is the world's largest contiguous mangrove forest with an area of about 10,000 square kilometers and shared between Bangladesh and India. This world-renowned mangrove forest, located on the lower Ganges floodplain and facing the Bay of Bengal, has long served as a crucial barrier, shielding southern coastal Bangladesh from cyclone hazards. However, the Sundarbans mangrove ecosystem is now increasingly threatened by climate-induced hazards, particularly tropical cyclones originating from the Indian Ocean. To assess the cyclone vulnerability of this unique ecosystem, using geospatial techniques, we analyzed the damage caused by past cyclones and the subsequent recovery across three salinity zones, i.e., Oligohaline, Mesohaline, and Polyhaline. Our study also examined the relationship between cyclone intensity with the extent of damage and forest recovery. The findings of our study indicate that the Polyhaline zone, the largest in terms of area and with the lowest elevation, suffered the most significant damage from cyclones in the Sundarbans region, likely due to its proximity to the most cyclone paths. A correlation analysis revealed that cyclone damage positively correlated with wind speed and negatively correlated with the distance of landfall from the center of the Sundarbans. With the expectation of more extreme weather events in the near future, the Sundarbans mangrove forest faces a potentially devastating outlook unless both natural protection processes and human interventions are undertaken to safeguard this critical ecosystem. [ABSTRACT FROM AUTHOR]

Hydrological Ecosystem Services (HES) are crucial components of environmental sustainability and provide indispensable benefits. The present study identifies critical hot and cold spots areas of HES in the Aglar watershed of the Indian Himalayan Region using six HES descriptors, namely water yield (WYLD), crop yield factor (CYF), sediment yield (SYLD), base flow (LATQ), surface runoff (SURFQ), and total water retention (TWR). The analysis was conducted using weightage-based approaches under two methods: (1) evaluating six HES descriptors individually and (2) grouping them into broad ecosystem service categories. Furthermore, the study assessed pixel-level uncertainties that arose because of the distinctive methods used in the identification of hot and cold spots. The associated synergies and trade-offs among HES descriptors were examined too. From method 1, 0.26% area of the watershed was classified as cold spots and 3.18% as hot spots, whereas method 2 classified 2.42% area as cold spots and 2.36% as hot spots. Pixel-level uncertainties showed that 0.57 km2 and 6.86 km2 of the watershed were consistently under cold and hot spots, respectively, using method 1, whereas method 2 identified 2.30 km2 and 6.97 km2 as cold spots and hot spots, respectively. The spatial analysis of hot spots showed consistent patterns in certain parts of the watershed, primarily in the south to southwest region, while cold spots were mainly found on the eastern side. Upon analyzing HES descriptors within broad ecosystem service categories, hot spots were mainly in the southern part, and cold spots were scattered throughout the watershed, especially in agricultural and scrubland areas. The significant synergistic relation between LATQ and WYLD, and sediment retention and WYLD and trade-offs between SURFQ and HES descriptors like WYLD, LATQ, sediment retention, and TWR was attributed to varying factors such as land use and topography impacting the water balance components in the watershed. The findings underscore the critical need for targeted conservation efforts to maintain the ecologically sensitive regions at watershed scale. [ABSTRACT FROM AUTHOR]

Mangrove forests, apart from their carbon sequestration and coastal protection benefits, provide a wide range of ecosystem services to people in tropical developing countries. Local people living in and around forests in the developing tropics also depend heavily on these mangrove ecosystem services for their livelihoods. This study examines the impact of mangrove ecosystem services on the livelihoods of people in Indian part of the Sundarbans—the largest contagious mangrove forest on earth. To achieve this objective, a household survey was undertaken to gather data on the diverse range of provisioning and regulating ES local people derived from mangrove forests living near the Indian Sundarbans. Surveys were carried out in nine villages across the Kultali, Basanti, and Gosaba blocks, involving over one hundred respondents. Our study reveals the active participation of locals in gathering various ecosystem services, with fishing and crab collection being the most common in the area. Due to numerous challenges in the agricultural sector, such as soil salinity and frequent extreme weather events, people increasingly depend on non-farming incomes, particularly fishing. A questionnaire was used to assess the dependence of local people on different ecosystem services. Some villages, such as Amlamethi, Satyanarayanpur, Mathurakhand, Vivekananda Palli, and Second Scheme, demonstrated a higher reliance on forest ecosystem services compared to other villages. The study indicates that the contribution of ecosystem services sometimes surpasses traditional activities like farming and daily contractual work. River transportation emerged as the most crucial service, followed by freshwater, food, and fiber. While certain resources like fuel, natural medicine, and genetic resources may not be prioritized, they still hold significance within the community, contrasting with ornamental resources, which are considered the least important. Our findings underscore the importance of preserving natural services in the Sundarbans forest, highlighting the need to conserve the mangrove ecosystem services to ensure the long-term well-being of local communities. [ABSTRACT FROM AUTHOR]

Due to its outstanding physical properties, CdTe is used to fabricate high efficiency solar cells. However, its high work function poses a challenge, and hence, to fabricate an efficient CdTe‐based solar cell, Cu‐doping may be useful. Here, we present the role of temperature‐dependent Cu‐doping in radio frequency sputter‐deposited CdTe films and the related changes occurring in their optical, electrical, structural and microstructural properties. For instance, Cu‐doping at different temperatures leads to an increase in the grain size and a reduction in the optical reflectance with increasing temperature. In addition, Kelvin probe force microscopy measurements reveal that the work function is found to be smaller corresponding to the annealing temperature of 473 K, whereas resistivity measurements show that it decreases with increasing temperature (the lowest value of resistivity is found to be 1.8 × 10−2 Ω‐cm). To understand the electronic structure of CdTe before and after Cu‐doping, we have carried out first‐principles density functional theory (DFT) simulation, which reveals a strong hybridization among Cu, Cd and Te atoms. This study paves the way to fabricate efficient Cu‐doped CdTe‐based solar cells. [ABSTRACT FROM AUTHOR]

In this work, the design of a high sensitivity hydrostatic pressure sensor based on one-dimensional photonic crystal (1DPC) containing polymeric materials has been proposed and investigated, theoretically. The proposed structure consists of alternate layers of polystyrene (PS) and polymethyl metahacrylate (PMMA) with a defect of layer of PS, PMMA, and air, respectively, in the middle of the PC structure. The sensing principle is based on the shift in the peak of transmitted wavelength when the hydrostatic pressure is applied on 1DPC. In order to obtain the transmission spectrum of 1DPC structure transfer matrix method (TMM) has been used. From the analysis it is found that with the increase in hydrostatic pressure transmission (or resonance) peak shifts towards the lower wavelength side with respect to the center wavelength. The average sensitivity (λ/P) of the proposed sensor is found about 0.948 (nm/MPa) with polymer defect and 0.92 (nm/MPa) with air defect in the mid-IR frequency region, and the applied pressure range is 0 to 200MPa. [ABSTRACT FROM AUTHOR]