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1.
ABSTRACTA novel approach is introduced for simulation of instantaneous unit hydrographs (IUHs). The model consists of a series of linear reservoirs that are connected to each other, and is referred to as the inter-connected linear reservoir model (ICLRM). By assuming the flow between two reservoirs is a linear function of the difference between the water levels in the reservoirs, a system of first-order linear differential equations is obtained as the ICLRM governing equation. By solving the equations, the discharge from the last reservoir is considered as an IUH. A small-scale laboratory device was constructed for the simulation of IUHs using the model. By studying four hydrographs extracted from the literature, and simulating them using both the ICLRM and the Nash model, it is concluded that the ICLRM can predict these hydrographs more accurately than the Nash model. Due to the simplicity of the construction and operation of the ICLRM and, more importantly, its visual aspect, the ICLRM may be considered as an effective educational tool for studying IUHs. 相似文献
2.
Parvin Sultana Paul Michael Thompson Naya Sharma Paudel Madan Pariyar Mujibur Rahman 《Climate Policy》2019,19(6):S94-S106
ABSTRACTSince the 1990s, climate change impact discourse has highlighted potential for large scale violent conflicts. However, the role of climate stresses on local conflicts over natural resources, the role of policies and adaptation in these conflicts, and opportunities to enhance cooperation have been neglected. These gaps are addressed in this paper using evidence from participatory action research on 79 cases of local collective action over natural resources that experience conflicts in Bangladesh and Nepal. Climate trends and stresses contributed to just under half of these conflict cases. Nine factors that enable greater cooperation and transformation of conflict are identified. Participatory dialogue and negotiation processes, while not sufficient, changed understanding, attitudes and positions of actors. Many of the communities innovated physical measures to overcome natural resource constraints, underlying conflict, and/or institutional reforms. These changes were informed by improving understanding of resource limitations and indigenous knowledge. Learning networks among community organizations encouraged collective action by sharing successes and creating peer pressure. Incentives for cooperation were important. For example, when community organizations formally permitted excluded traditional resource users to access resources, those actors complied with rules and paid towards management costs. However, elites were able to use policy gaps to capture resources with changed characteristics due to climate change. In most of the cases where conflict persisted, power, policy and institutional barriers prevented community-based organizations from taking up potential adaptations and innovations. Policy frameworks recognizing collective action and supporting flexible innovation in governance and adaptation would enable wider transformation of natural resource conflicts into cooperation.Key policy insights
Climate stresses, policy gaps and interventions can all worsen local natural resource conflicts.
Sectoral knowledge and technical approaches to adaptation are open to elite capture and can foster conflicts.
Many local natural resource conflicts can be resolved but this requires an enabling environment for participatory dialogue, external facilitation, flexible responses to context, and recognition of disadvantaged stakeholder interests.
Transforming conflict to greater cooperation mostly involves social and institutional changes, so adaptation policies should focus less on physical works and more on enabling factors such as negotiation, local institutions, knowledge, and incentives.
3.
The legal regime of the Caspian Sea has been determined under Treaties 1921 and 1940 by and between Iran and former Soviet Union. In fact, we are neither to explain it nor to determine. As understood from the provisions therein, the exploitation and use of the Caspian Sea by both countries are based on the Condominium. However, there is a 10-nautical mile strip as exclusive fishing areas which have been allocated to the states under the 1940 treaty. It means that Soviet Union and Iran may benefit the marine livings resources out of that strip on an equal manner. This right also includes the seabed and underlying bed. So, the legal regime of this sea may be based on a 10-nautical mile exclusive region for all five states and the remaining part as common and joint area under an agreement until an explaining and supervising organization is established to exploit and supervise over living and non-livings resources. 相似文献
4.
Pham Quoc Bao Ali Sk Ajim Bielecka Elzbieta Calka Beata Orych Agata Parvin Farhana Łupikasza Ewa 《Natural Hazards》2022,113(2):1043-1081
Natural Hazards - Advances in the availability of multi-sensor, remote sensing-derived datasets, and machine learning algorithms can now provide an unprecedented possibility to predict flood events... 相似文献
5.
Response of microbial community to petroleum stress and phosphate dosage in sediments of Jiaozhou Bay,China 总被引：1，自引：0，他引：1
ZHAO Yangguo CHEN Min BAI Jie LI Xinwei Farhana Zulfiqar and WANG Qianli 《中国海洋大学学报(英文版)》2014,13(2):249-256
The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation. 相似文献
6.
Passive earth pressure on embedded anchor plates constitutes a viable resisting force for the design of underground structures. In the current practice, these forces are empirically calculated, ignoring the effects of the depth of embedment and the level of consolidation of the surrounding soil, which takes place during plate installation on the in situ stress levels. Accordingly, wide discrepancies between predicted and measured pullout capacities of these plates were reported in the literature. Numerical model was developed using finite-element technique and the constitutive law of Mohr?CCoulomb to simulate the case of a retaining wall partially supported by an embedded anchor plate in sand. The results produced in this investigation showed that the passive earth pressure acting on anchor plates increases due to the increase of angle of shearing resistance and the overconsolidation ratio of sand, and it decreases due to an increase of the embedment depth of anchor. Design theories were developed for the case of embedded anchor plate in overconsolidated sand. The theories developed will satisfy the design needed in terms of allowable pullout load and/or displacement. 相似文献
7.
Farhana Sultana 《The Professional geographer》2013,65(3):372-381
Although climate change is expected to increase vulnerabilities, marginalization, and sufferings of many in the Global South, impacts will be unevenly felt across social strata. Intersectionalities of social difference, especially along gender and class lines, differentiate the ways in which impacts of climate change are experienced and responded to. Feminist political ecology and feminist geography insights can explain how different groups of people understand, respond to, and cope with variability and uncertainties in nuanced and critical ways, thereby elucidating the gendered implications of climate change. With a regional focus on South Asia, the article underscores the key issues that can be applied geographically elsewhere. Gendered implications of climate change in South Asia are particularly poignant as patriarchal norms, inequities, and inequalities often place women and men in differentiated positions in their abilities to respond to and cope with dramatic changes in socioecological relations but also foreground the complex ways in which social power relations operate in communal responses to adaptation strategies. This is particularly evident in water-related productive and reproductive tasks in agrarian societies that constitute the majority of South Asia. As climate change is expected to exacerbate both ecological degradation (e.g., water shortages) and water-related natural hazards (e.g., floods, cyclones), thereby transforming gender–water geographies, it becomes imperative to undertake careful multiscalar and critical analyses to better inform policymaking. This article elucidates the complex ways that climate change will affect gender and social relations, thereby highlighting the ways that existing policy narratives and adaptation programs might be better informed by geographical insights. To this end, the article encourages feminist and critical geographers to more forcefully and fruitfully engage with global debates on climate change. 相似文献
8.
Farhana Huq Philipp Blum Michael A. W. Marks Marcus Nowak Stefan B. Haderlein Peter Grathwohl 《Environmental Earth Sciences》2012,67(2):385-394
Dissolution?Cprecipitation phenomena induced by CO2 injection to Altmark Permian sandstone were observed through laboratory experiments carried out under simulated reservoir conditions (125?°C and 50 bars of pressure). The rock sample was collected from the Altmark gas reservoir, which is being considered for enhanced gas recovery. Two sets of experiments were performed with pulverized rock samples in a closed batch reactor with either pure water (run 1) or 3?M aqueous NaCl solution (run 2) and reacted with injected CO2 for 3, 5, and 9?days. The liquid samples were analyzed by inductively coupled plasma optical emission spectroscopy and total reflection X-ray fluorescence, where the latter proved to be a feasible alternative to conventional analytical techniques, especially since only small sample volumes (about 10???l) are needed. Chemical analysis for both fluids (water and NaCl brine) indicated a significant dissolution of calcite and anhydrite in the solution, which might be a crucial process during CO2 injection. The brine solution enhanced the dissolution of calcite and anhydrite compared to pure water at the beginning of the reaction. Moreover, the progressive higher Si4+/Al3+ molar ratios (in average by a factor of 3) in the brine experiments indicated quartz dissolution. Thermodynamic calculations of mineral saturation indices highlighted the dissolution of the Ca-bearing minerals, which was in agreement with experimental results. Modeling enabled an evaluation of the dissolution processes of minerals in a low-salinity region, yet hindrances to model more saline conditions emphasize the need for further laboratory studies in order to parameterize models for deep aquifer conditions. 相似文献
9.
Davoud Agha‐Aligol Mohammad Lamehi‐Rachti Parvin Oliaiy Farah Shokouhi Mohammad Farmahini Farahani Mahmoud Moradi Fatemeh Farshi Jalali 《Geoarchaeology》2015,30(3):261-270
It had long been thought that obsidian found in Iranian sites originated from Anatolia and Armenia, but new research has challenged this assumption. In this study, 68 samples of obsidian obtained from an archaeological survey of Nader‐Tepe Aslanduz were analyzed by Proton Induced X‐ray Emission (PIXE). Nader‐Tepe Aslanduz is a tell site west of the city of Aslanduz in the Parsabad county of the Ardebil province in northern Iran. The site was inhabited from the first millennium B.C. to A.D. 17, and its history may extend back to the third or fourth millennium B.C. Our chemical composition results have been combined with obsidian composition data from Turkey and Armenia and subjected to Principal Component Analysis (PCA). This analysis shows that obsidian from each location can be grouped into distinctive classes—the obsidian from Nader‐Tepe Aslanduz is therefore probably derived from volcanic outcrops of the Sahand and Sabalan region. This study has been unable to assign a known source from Anatolia and Armenia for the obsidian of Nader‐Tepe Aslanduz. 相似文献
10.
Farhana Sultana 《Geoforum》2011,42(2):163-172
This article argues that resource access, use, control, ownership and conflict are not only mediated through social relations of power, but also through emotional geographies where gendered subjectivities and embodied emotions constitute how nature-society relations are lived and experienced on a daily basis. By engaging the insights from feminist political ecology literatures and emotional geographies literatures, the article demonstrates that resource struggles and conflicts are not just material challenges but emotional ones, which are mediated through bodies, spaces and emotions. Such a focus fleshes out the complexities, entanglements and messy relations that constitute political ecologies of resources management, where practices and processes are negotiated through constructions of gender, embodiments, and emotions. Abstractions of ‘resource struggles’ and ‘resource conflicts’ are thereby grounded in embodied emotional geographies of places, peoples, and resources, enabling us to better understand the ways resources and emotions come to matter in everyday survival struggles. This framing can enrich feminist political ecology theorizations and texture our understandings of commonly-used terms such as access, use, control, conflict and struggles vis-à-vis natural resources in any context. In other words, we are better able to conceptualize and explain how and why people access, use, and struggle over resources the ways they do. A case study of drinking water contamination from Bangladesh is used to develop the theoretical arguments in contributing to existing debates in (feminist) political ecologies. 相似文献