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321.
Coastal deforestation in the Ayeyarwady Delta, Myanmar (formerly Burma) is addressed through the promotion of native-species
mangrove plantations on cleared land formerly sustaining natural mangrove forests. To date there are no attempts to determine
the optimal mangrove plantation strategy to maximize economic returns for private or communal plantation owners. We integrated
empirical biological and economic data to suggest optimal mangrove plantation strategies in the region. We censused 4-yr oldAvicennia officinalis mangrove plantations in two townships to calculate survival and growth rates of mangroves planted using different techniques
across an inundation gradient. We used the calculated rates to forecast the production of fuelwood, poles and posts at 10,
13 and 15 yr after establishment. We calculated the compound rate of growth for the three commodities over a 7-yr period,
and then forecast commodity price for the same harvestintervals. Integration of those parameters in our model led us to conclude
that both profit and the internal rate of return would be greatest for plantations of seedlings raised in polyethylene bags
as opposed to bare-root or direct propagule planting. Therefore, the use of potted seedlings should be promoted, despite higher
initial costs. The optimal rotation period varies according to ground level and planting technique. Optimizing economic returns
for coastal plantations does not necessarily require a sacrifice of ecological benefits.
Due to a discrepancy between official conversion quotes and local real value no conversion estimate in USD is given. 相似文献
322.
Ritchie William 《Journal of Coastal Conservation》2000,6(1):207-218
The Sands of Forvie, National Nature Reserve, Scotland is a complex coastal sand dune system which is associated with the
dynamic estuary of the River Ythan. The dune system has developed over more than 5000 years. The south partis a peninsula
of dunes, sandhills, sand arcs, erosion and deflation surfaces. The north part is superimposed on a rock plateau with a cliff
coastline. This plateau is covered in glacial deposits and is essentially an upland heath landscape. Some of the best examples
of large active parabolic dunes in Britain are found in North Forvie. The sequence of geomorphic development is described.
As a nature reserve with a rich ecology it has been managed for conservational purposes since 1960s. As such it is an excellent
case study of how conservational management has changed to become more flexible and more aware of the importance of dynamic
processes. 相似文献
323.
The Dutch province of Zeeland is situated in the southern part of the Delta region. The geographical location of the province
and its history of inundation, land reclamation and dam-building, clearly illustrate the importance that water always has
had and still has in The Netherlands. Coastal defence projects are of utmost importance for The Netherlands and the Delta
Project is the crown project.
The importance of this project does not only regard the protection against the sea; the Delta dams also contribute considerably
to the regional infrastructure. They are a important contribution to the abolishment of the former isolation of the region.
They control inland navigation and form important boundaries for water management. They separate salt, brackish and fresh
water as well as waters with or without tidal-influence and they also influence the ecological systems in and along the waters.
Through physical planning, including the coastal policy of today, land and water can be further integrated. This paper discusses
the role of the Province in area planning, related to the division of labour between the various public authorities in The
Netherlands: state, provinces and municipalities. Coastal and water policy at the provincial level have been largely integrated
with relevant other interests.
It may be concluded that regional planning and coastal policy are beginning to adopt a new view towards dealing with water. 相似文献
324.
Megan MH Nash MS Neale AC Pitchford AM 《Environmental monitoring and assessment》2007,124(1-3):141-156
The objective of this study was to assess the applicability of using landscape variables in conjunction with water quality
and benthic data to efficiently estimate stream condition of select headwater streams in the Mid-Atlantic Coastal Plains.
Eighty-two streams with riffle sites were selected from eight-two independent watersheds across the region for sampling and
analyses. Clustering of the watersheds by landscape resulted in three distinct groups (forest, crop, and urban) which coincided
with watersheds dominant land cover or use. We used non-parametric analyses to test differences in benthos and water chemistry
between groups, and used regression analyses to evaluate responses of benthic communities to water chemistry within each of
the landscape groups. We found that typical water chemistry measures associated with urban runoff such as specific conductance
and dissolved chloride were significantly higher in the urban group. In the crop group, we found variables commonly associated
with farming such as nutrients and pesticides significantly greater than in the other two groups. Regression analyses demonstrated
that the numbers of tolerant and facultative macroinvertebrates increased significantly in forested watersheds with small
shifts in pollutants, while in human use dominated watersheds the intolerant macroinvertebrates were more sensitive to shifts
in chemicals present at lower concentrations. The results from this study suggest that landscape based clustering can be used
to link upstream landscape characteristics, water chemistry and biotic integrity in order to assess stream condition and likely
cause of degradation without the use of reference sites. Notice: Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency
policy. 相似文献
325.
The high conservational value of the lichen-rich vegetation and landscape of the marine foreland Ørkenen on the isle of Anholt is treated from a Danish as well as a European perspective. The sensitivity of the lichen-rich vegetation to physical disturbance is emphasized. The impact of invasive species such asPinus mugo as well as the effect of atmospheric deposition of nutrients on the heaths at Anholt is described. Considerations related to the development of a management plan for Ørkenen are presented. 相似文献
326.
Persistent bioaccumulative and toxic (PBT) pollutants are chemical contaminants that pose risks to ecosystems and human health.
For these reasons, available tissue contaminant data from the US EPA Environmental Monitoring and Assessment Program’s National
Coastal Assessment were examined to estimate to what areal extent PBTs are found in US estuarine resources. The data document
composite, whole-body tissue chemical concentrations for 736 sampling sites across Northeast, Southeast, Gulf of Mexico, and
West Coast estuaries. Tissue chemical concentrations were compared to US EPA non-cancer risk guidelines for recreational fishers,
because of a lack of ecological guidelines for these chemical concentrations. Samples were analyzed for 23 PAH compounds,
21 PCB congeners, 6 DDT derivatives and metabolites, 14 chlorinated pesticides (other than DDT) and 13 metals, including mercury.
Total PCBs were found to exceed recreational fisher guidelines most frequently (31% of samples evaluated), followed by mercury
(29%), total PAHs (21%), and DDT and its metabolites, DDD and DDE (11%). Toxaphene, cadmium and dieldrin were found but in
fewer than 1% of the samples. 相似文献
327.
Wilfredo Y. Licuanan Maricar S. Samson Samuel S. Mamauag Laura T. David Roselle Borja-del Rosario Miledel Christine C. Quibilan Fernando P. Siringan Ma. Yvainne Y. Sta. Maria Norievill B. España Cesar L. Villanoy Rollan C. Geronimo Olivia C. Cabrera Renmar Jun S. Martinez Porfirio M. Aliño 《Ambio》2015,44(8):718-736
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users. 相似文献328.
我国海岸带灾害的加剧发展及其防御方略 总被引:9,自引:0,他引:9
中国大陆海岸带绵长1.8万公里,地跨12个省市,是我国人口密集、经济发展最快的地区。出现的严重灾害有台风、风暴潮、洪涝、地震海啸、海岸侵蚀、盐水入侵、海冰、地基下沉、污染、赤潮等十类,并互相叠加,形成年直接经济损失100亿元以上。全球海平面上升与人类活动加强,使海岸带灾害加剧发展,粗略估计到下世纪初中期,导致的损失可能达到1000亿元以上,是海岸带经济发展的重要制约因素。必须提高全民防灾意识,在调查研究基础上,拟订海岸带减灾规划;加强灾害的监测、预报和预警;加高加固防潮防洪大堤与护岸工程,疏浚内陆洼地和城市排洪河道,提高排水能力;保护地下水源,严格限制过量开采,以防止地面下沉和盐水入侵;合理开发海岸带资源,保护生态环境,严格限制超标排污;积极参加国际合作,逐步限制CO_2等温室气体的排放,和缓海平面上升趋势,争取大幅度减轻海岸带灾害。 相似文献
329.
根据2006年10月野外调查数据及1998年的LANDSAT 5卫星影像解译的辽宁省植被类型数据,以辽宁省滨海公路沿线植被生态系统为研究对象,运用ARCVIEW3.3、ARCGIS9.0和FRAGSTATS3.3软件研究辽宁省滨海公路建设对沿线生态系统结构的影响,结果表明:①辽宁省滨海公路跨越2个纬度和5个经度,沿线主要植被类型以湿地生态系统和农业生态系统为主。②辽宁省滨海公路的建设对生态系统产生直接的切割,使景观更加破碎。③辽宁省滨海公路的建设直接破坏沿线植被生态系统(主要为50m缓冲区内),损失总净初级生产量为25778.39 t/a,损失总生物量199274.2~284380.6t/a。建议采取一些必要的环境保护及生态恢复性措施。 相似文献
330.
Jharyathri Thiagarajah Shermaine K. M. Wong Daniel R. Richards Daniel A. Friess 《Ambio》2015,44(7):666-677
Cultural ecosystem services are a function of people and place, so may change as a location transitions from rural to urban. Singapore has undergone rapid urbanization after its independence in 1965, with a concomitant decline in natural habitat extent and accessibility. Using coastal mangrove forests as a case study habitat, changing cultural values were explored with a novel array of techniques, including qualitative archival analysis (photographs, oral histories), current sources (publically uploaded social media photographs), and surveys of (a) the general public and (b) visitors to publically accessible mangroves. Cultural value changed through time, with a significant transition from intrinsic, intrapersonal values (spiritual, cultural heritage) to instrumental, interpersonal values (recreation, education). Additionally, cultural value varied between different mangroves depending on their public accessibility, and the evolving degree of human interaction with the ecosystem as urban development occured. Cultural values change as development transitions, though mangroves still play an important cultural role in a heavily urbanized environment. 相似文献