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21.
Reimo Rivis Are Kont Urve Ratas Valdeko Palginõmm Kait Antso Hannes Tõnisson 《Journal of Coastal Conservation》2016,20(3):199-209
The structure of coastal land cover in Estonia is intricate and exhibits considerable differences from site to site. The diverse geomorphology of the seashores is one of the key factors affecting the speed and magnitude of land cover changes. Likewise, the history of human inhabitance on the coast has also shaped the character of land cover. The Estonian coastal zone has experienced abrupt and radical changes in land ownership and its related land use during the last century. The main objectives of this paper are: 1) to give an overview of land use and the trends of development of land cover pattern along different parts of the Estonian coast; and 2) to analyze the relationships of natural and human processes and their cumulative impact on the evolution of coastal land cover pattern in Estonia. This study is based on results obtained during fieldwork in the study areas and on the analysis of large-scale (1:10,000) historical maps. In agriculturally dominant coastal areas, the traditional open landscape of fields and grassland at the beginning of the 20th century had been replaced by woodland and grasslands with shrubs by the start of the 21st century. Expansion of reed beds in areas of former seashore grasslands is another striking phenomenon. The structure of land cover on forested coasts has been fairly stable during the last 100 years. Areas of urban sprawl are characterised by dramatic changes in land cover structure. Rapidly increasing population and expanding settlements imposes on the ecological balance of the fragile dune forests in the coastal zone. 相似文献
22.
K.R. Renjith V. Sudheesh Anu Shaji Ejin George Manju Mary Joseph C.S. Ratheesh Kumar 《毒物与环境化学》2016,98(1):36-52
The spatial and temporal variations of some trace metals in the surface sediments of Cochin Estuary were analyzed along with their geochemical associations to identify the possible sources, bioavailability and the health risks posed by them. The dominance of kaolinite and suggested that clay minerals distribution is influenced by sediment sorting. Total metal analysis revealed enrichment for Cd, Pb and Zn due to anthropogenic activities. The speciation analysis established that notwithstanding the large availability, carbonate as well as organic and sulfides bound fractions showed negligible associations with most of the metals. Hydrous Fe–Mn oxides appeared to play a major role in controlling the fate and transport of these metals in the sediments of Cochin Estuary. Lower contribution of the residual fractions for Cd (21%–26%), Pb (<60%) and Zn (24%–42%) indicated an obvious increase of other geochemical fractions. Risk assessment analysis revealed that regardless of total concentration, none of the analyzed metals were at safe levels in the estuary as appreciable percentages were found to be associated with mobile geochemical forms. The speciation study conspicuously established that the metals originating from non-geogenic sources are largely associated with the labile fractions and hence are more detrimental to the aquatic biota. 相似文献
23.
Jeremy R. Brammer Nicolas D. Brunet A. Cole Burton Alain Cuerrier Finn Danielsen Kanwaljeet Dewan Thora Martina Herrmann Micha V. Jackson Rod Kennett Guillaume Larocque Monica Mulrennan Arun Kumar Pratihast Marie Saint‐Arnaud Colin Scott Murray M. Humphries 《Conservation biology》2016,30(6):1277-1287
Many argue that monitoring conducted exclusively by scientists is insufficient to address ongoing environmental challenges. One solution entails the use of mobile digital devices in participatory monitoring (PM) programs. But how digital data entry affects programs with varying levels of stakeholder participation, from nonscientists collecting field data to nonscientists administering every step of a monitoring program, remains unclear. We reviewed the successes, in terms of management interventions and sustainability, of 107 monitoring programs described in the literature (hereafter programs) and compared these with case studies from our PM experiences in Australia, Canada, Ethiopia, Ghana, Greenland, and Vietnam (hereafter cases). Our literature review showed that participatory programs were less likely to use digital devices, and 2 of our 3 more participatory cases were also slow to adopt digital data entry. Programs that were participatory and used digital devices were more likely to report management actions, which was consistent with cases in Ethiopia, Greenland, and Australia. Programs engaging volunteers were more frequently reported as ongoing, but those involving digital data entry were less often sustained when data collectors were volunteers. For the Vietnamese and Canadian cases, sustainability was undermined by a mismatch in stakeholder objectives. In the Ghanaian case, complex field protocols diminished monitoring sustainability. Innovative technologies attract interest, but the foundation of effective participatory adaptive monitoring depends more on collaboratively defined questions, objectives, conceptual models, and monitoring approaches. When this foundation is built through effective partnerships, digital data entry can enable the collection of more data of higher quality. Without this foundation, or when implemented ineffectively or unnecessarily, digital data entry can be an additional expense that distracts from core monitoring objectives and undermines project sustainability. The appropriate role of digital data entry in PM likely depends more on the context in which it is used and less on the technology itself. 相似文献
24.
Leila Mehrparvar Siyamak Safapour Mousa Sadeghi-Kiakhani Kamaladin Gharanjig 《Environmental Chemistry Letters》2016,14(4):533-539
The classical use of synthetic dyes is causing issues of environmental pollution and heath risk. As a consequence natural dyes are gaining interest, but the use of natural dyes still includes toxic reagents such as metals as mordants and acids to enhance color and yield. Therefore, we designed a new chitosan-polypropylene imine dendrimer hybrid at 0–2000 mg/L to treat wool before dyeing with cochineal. We compared dye exhaustion, color depth, color characteristics, and color fastness of the new process with dyed pristine and metal mordanted wool. Results show that wool pretreatment improved dye exhaustion from 48 to 88 %, shifted saturation point toward lower dye concentration from 3000 to 1000 mg/L, and improved color depth from 13.68 for pristine wool and 15.17 for metal mordanted wool to 23.89 for the new process. 相似文献
25.
Kaushik Lav Kumar Mahalingam Arun Kumar Palanisamy Muthukumar 《Environmental science and pollution research international》2021,28(10):12168-12177
Environmental Science and Pollution Research - In this paper, the combustion characteristics of biogas in a Porous Radiant Burner (PRBBG) designed for domestic cooking appliances are presented.... 相似文献
26.
Shahi Nirmal Kumar Maeng Minsoo Kim Donghyun Lee Taehoon Dockko Seok 《Environmental science and pollution research international》2021,28(30):40598-40607
Environmental Science and Pollution Research - Dissolved air flotation (DAF) is a widely used treatment process in drinking water and wastewater treatment plants despite high energy cost associated... 相似文献
27.
Kaur Sandeep Kumar Ajay Pandit Kritika Kaur Satwinderjeet 《Environmental science and pollution research international》2021,28(6):6619-6634
Environmental Science and Pollution Research - The present study investigated the antimutagenic, antioxidant, and antiproliferative properties of extracts of Cassia fistula prepared by sequentially... 相似文献
28.
Deepak Anurag Kumar Dinesh Sharma Varun 《Environmental science and pollution research international》2021,28(45):64014-64029
Environmental Science and Pollution Research - The waste from healthcare facilities (HCFs) is most devastating as they induce health hazards and pollute the environment. The effective management of... 相似文献
29.
Pal Kalyanbrata Rakshit Subham Mondal Keshab Chandra Halder Suman Kumar 《Environmental science and pollution research international》2021,28(42):58915-58928
Environmental Science and Pollution Research - Crustacean shell waste disposal is considered as biggest problem in seafood processing centers. Incineration and landfilling are the commonest ways of... 相似文献
30.
Rakesh Kumar Pathak A. Ravi Kumar G.K. Ananthasuresh 《Journal of Manufacturing Processes》2013,15(1):108-114
This work demonstrates the feasibility of meso-scale (100 μm to mm) punching of multiple holes of intricate shapes in metals. Analytical modeling, finite element (FE) simulation, and experimentation are used in this work. Two-dimensional FE simulations in ABAQUS were done with an assumed material modeling and plane-strain condition. A known analytical model was used and compared with the ABAQUS simulation results to understand the effects of clearance between the punch and the die. FE simulation in ABAQUS was done for different clearances and corner radii of the punch, die, and holder. To complement modeling with real experiments and for the purpose of comparison, a set of punches and dies were made to punch out a miniature spring-steel gripper. Comparison of compliant grippers made by wire-cut electro discharge machining (EDM) and punching shows that realizing sharp interior and re-entrant corners by punching is not easy to achieve. However, the promise of realizing meso-scale parts with complicated shapes through punching is demonstrated in this work; and further work is identified and some strategies are suggested for improvement. The main contribution of this paper is in adapting the well-established punching and blanking operations to the meso-scale as a viable alternative to making miniature devices currently dominated by lithography-based techniques. 相似文献