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31.
The performance of 33 countries was evaluated for ecosystem-based management (EBM) of fisheries in three fields (principles, criteria and implementation) using quantitative ordination including uncertainty. No country rated overall as ‘good’, only four countries were ‘adequate’, while over half received ‘fail’ grades. A few developing countries performed better than many developed nations. Two case studies test the method. In Indonesia, Raja Ampat and Papua, rated similar to the national evaluation, but better performance might follow successful implementation of a planned EBM initiative. A workshop in Australia rated regional fisheries managed by New South Wales 20% lower for EBM than federally managed fisheries.  相似文献   
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Safety is the topmost priority considered by the designers of floating systems or any other structural systems. Reliability, economy and environmental pollutions and the liability of the structure in the case of accidents are also considered by the designers. The paper concentrates on the non-linear behavior of a moored floating platform in stochastic seaway generated using the Pierson–Moskowitz spectrum. Second-order wave forces (slow drift force) acting on the structure is considered as they contribute to a major percentage of the excursion of a large platform. Wave drift damping and skin friction damping have also been considered.It has been shown that the principal frequency of the second-order motion of the platform due to drift forces closely matches the natural frequency of the system in surge motion. This has been subsequently used in tuning a PID (proportionate integral and differential)-based control system for the surge mode, where reduction in the order of 90% has been observed.  相似文献   
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Though irrigation with sewage water has potential benefits of meeting the water requirements, the sewage irrigation may mess up to harm the soil health. To assess the potential impacts of long-term sewage irrigation on soil health and to identify sensitive soil indicators, soil samples were collected from crop fields that have been irrigated with sewage water for more than 20 years. An adjacent rain-fed Leucaena leucocephala plantation system was used as a reference to compare the impact of sewage irrigation on soil qualities. Soils were analyzed for different physical, chemical, biological and biochemical parameters. Results have shown that use of sewage for irrigation improved the clay content to 18–22.7%, organic carbon to 0.51–0.86% and fertility status of soils. Build up in total N was up to 2,713 kg ha−1, available N (397 kg ha−1), available P (128 kg ha−1), available K (524 kg ha−1) and available S (65.5 kg ha−1) in the surface (0.15 m) soil. Long-term sewage irrigation has also resulted a significant build-up of DTPA extractable Zn (314%), Cu (102%), Fe (715%), Mn (197.2), Cd (203%), Ni (1358%) and Pb (15.2%) when compared with the adjacent rain-fed reference soil. Soils irrigated with sewage exhibited a significant decrease in microbial biomass carbon (−78.2%), soil respiration (−82.3%), phosphatase activity (−59.12%) and dehydrogenase activity (−59.4%). An attempt was also made to identify the sensitive soil indicators under sewage irrigation, where microbial biomass carbon was singled out as the most sensitive indicator.  相似文献   
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Yadava  Pramod Kumar  Soni  Manish  Verma  Sunita  Kumar  Harshbardhan  Sharma  Ajay  Payra  Swagata 《Natural Hazards》2020,101(1):217-229
Natural Hazards - Lightning, a climate-related highly localized natural phenomenon, claims lives and damage properties. These losses could only be reduced by the identification of active seasons...  相似文献   
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Pramod Singh 《Chemical Geology》2010,269(3-4):220-236
Major, trace and REE compositions of sediments from the upper Ganga River and its tributaries in the Himalaya have been examined to study the weathering in the Himalayan catchment region and to determine the dominant source rocks to the sediments in the Plains. The Ganga River rises in the Higher Himalaya from the Higher Himalayan Crystalline Series (HHCS) bedrocks and traverses over the Lesser Himalayan Series (LHS) and the Himalayan foreland basin (Siwaliks) rocks before entering into the Gangetic Plains. The major element compositions of sediments, reflected in their low CIA values (45.0–54.7), indicate that silicate weathering has not been an important process in the Himalayan catchment region of the Ganga River. Along the entire traverse, from the HHCS through LHS and the Siwaliks, the sediments from the tributaries and the mainstream Ganga River show higher Na2O, K2O, CaO and silica. This, and the higher ratios of La/Sc, Th/Sc and lower ratios of Co/Th, suggest that the source rocks are felsic. The fractionated REE patterns and the significant negative Eu anomalies (Eu/Eu? = 0.27–0.53) indicate highly differentiated source. Moreover, the comparison of the sediments with different source rock lithologies from the HHCS and the LHS for their major elements clearly suggests that the HHCS rocks were the dominant source. Further, comparison of their UCC (upper continental crust) normalized REE patterns suggests that, among the various HHCS rocks, the metasediments (para-gneiss and schist) and Cambro-Ordovician granites have formed the major source rocks. The Bhagirathi and Alaknanda River sediments are dominantly derived from metasediments and those in the Mandakini River from Cambro-Ordovician granites. The resulting composition of the sediments of the Ganga River is due to the mixing of sediments supplied by these tributaries after their confluence at Devprayag. No further change in major, trace and rare earth element compositions of the sediments of the Ganga River after Devprayag up to its exit point to the Plains at Haridwar, suggests little contribution of the Lesser Himalayan and Siwalik rocks to the Ganga River sediments.  相似文献   
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The present investigation was conducted to analyze the temporal patterns of snow cover area%(SCA%), air temperature, snowfall and river discharge in parts of Chenab basin, western Himalayas. The relationship of mean SCA% with mean air temperature and river discharge was also tested using Pearson's product-moment correlation at 95% confidence limit and further sensitivity analysis of river discharge to SCA and SCA to air temperature was performed. Moderate Resolution Imaging Spectroradiometer(MODIS) 8-day surface reflectance product MOD09A1 was used to delineate SCA during the period 2000–2013. Moreover, variation in the lowest elevation from where snow cover area starts(LESCA) was also analyzed and its relationship with mean air temperature was also studied. Non-parametric method, Mann-Kendall test was employed to determine the trend in the SCA%, air temperature, snowfall and river discharge. The investigation carried out for three meteorological stations i.e. Batote, Reasi and Tandi revealed significant findings. At Batote and Reasi, statistically significant decreasing trends were observed over the period 2000 to 2012, for maximum, minimum and mean air temperature. Mean minimum SCA% exhibited a significant upward trend during 2000–2013 which is corroborated by the significantly increasing trend of mean annual snowfall(Tandi station) from 2000 to 2010. Further, significant decreasing trend of river discharge for the winter season at Batote station from 2000 to 2011 and decreasing trends in the maximum, minimum and mean air temperature at Batote and Reasi stations are also consistent with the increasing trend of SCA%. At both Batote and Reasi stations, mean SCA% exhibited significant negative relationship with the mean air temperature. On the other hand, LESCA exhibited positive correlation with the mean air temperature except in a few months, where negative relationship was seen. Sensitivity analysis of river discharge to SCA exhibited very low values of sensitivity coefficient in most of the months, indicating less sensitivity of river discharge to SCA. On the other hand, sensitivity coefficient of SCA to air temperature exhibited comparatively higher values which indicate SCA is more sensitive to air temperature.  相似文献   
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The Nationally Determined Contributions (NDCs) submitted under the Paris Agreement propose a country’s contribution to global mitigation efforts and domestic adaptation initiatives. This paper provides a systematic analysis of NDCs submitted by South Asian nations, in order to assess how far their commitments might deliver meaningful contributions to the global 2°C target and to sustainable broad-based adaptation benefits. Though agriculture-related emissions are prominent in emission profiles of South Asian countries, their emission reduction commitments are less likely to include agriculture, partly because of a concern over food security. We find that income-enhancing mitigation technologies that do not jeopardize food security may significantly augment the region’s mitigation potential. In the case of adaptation, analysis shows that the greatest effort will be directed towards protecting the cornerstones of the ‘green revolution’ for ensuring food security. Development of efficient and climate-resilient agricultural value chains and integrated farming bodies will be important to ensuring adaptation investment. Potentially useful models of landscape level climate resilience actions and ecosystem-based adaptation are also presented, along with estimates of the aggregate costs of agricultural adaptation. Countries in the region propose different mixes of domestic and foreign, and public and private, adaptation finance to meet the substantial gaps.

Key policy insights

  • Though substantial potential for mitigation of agricultural emissions exists in South Asia, governments in the region do not commit to agricultural emissions reductions in their NDCs.

  • Large-scale adoption of income-enhancing technologies is the key to realizing agricultural mitigation potential in South Asia, whilst maintaining food security.

  • Increasing resilience and profitability through structural changes, value chain interventions, and landscape-level actions may provide strong options to build adaptive capacity and enhance food security.

  • Both private finance (autonomous adaptation) and international financial transfers will be required to close the substantial adaptation finance gap

  相似文献   
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