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991.
陆玲 《城市环境与城市生态》2001,14(5):18-19
根据广义生态学关于宇宙生物统一性的原理,借助动物神经学和生物遗传学的有关理论,探讨了区域经济因素复合性条件反射的一般运动规律。区域经济生态系统机能系统有序运动的规律;区域经济生态系统细胞多性状融合与分化的规律;区域经济生态系统基因物质遗传和变异的规律。 相似文献
992.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years,
the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled
fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus
influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development
policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales
of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences
of development plans are seldom considered). Some international conservation organizations are testing promising new approaches
to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful
examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources,
they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance
agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected
areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered
as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with
the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major
role in the design and implementation of any fishing management actions. 相似文献
993.
J. S. Mani 《Journal of Coastal Conservation》2001,7(1):23-30
The Chennai coast, an integral part of the east coast of India, extends over ca. 35 km. Over the past 120 yr the coastline
has witnessed both man-made and natural disturbances which led to the destruction of the beach front. The construction of
Madras harbour in 1876, was the prime cause of the degradation of this very sensitive coastal region. Continued growth of
Madras harbour has helped in the natural formation of the wide ‘Marina Beach’, south of the harbour. But the shoreline north
of the harbour suffered the consequences of harbour development activities. The north shore receded by ca. 500 m over the
past 120 yr and received attention from the authorities in the past few decades because of the growing awareness of the conservation
value of the coast. This paper highlights the effects of Madras harbour development on the adjoining coast and on the shortterm
mitigation measures planned and executed by the Government agencies to protect the fragile coastline. In spite of sincere
efforts to protect the coastline, the destruction continues unabated due to various reasons. This paper analyses the facts
and suggests a long-term solution to protect the coastline and to regain the past glory. Feasible and cost effective permanent
measures are identified, construction methods suggested and the advantages that the community can derive from the longterm
solutions are discussed. 相似文献
994.
We predict the decadal change in position of three American Samoa mangroves from analysis of a time series of remotely sensed
imagery, a geographic information system, tide gauge data, and projections for change in sea-level relative to the mangrove
surface. Accurate predictions of changes to coastal ecosystem boundaries, including in response to projected relative sea-level
rise, enable advanced planning to minimize and offset anticipated losses and minimize social disruption and cost of reducing
threats to coastal development and human safety. The observed mean landward migration of three mangroves' seaward margins
over four decades was 25, 64, and 72mma−1, 12 to 37 times the observed relative sea-level rise rate. Two of the sites had clear trends in reductions in mangrove area,
where there was a highly significant correlation between the change in position of the seaward mangrove margin and change
in relative sea-level. Here it can be inferred that the force of sea-level rise relative to the mangrove surface is causing
landward migration. Shoreline movement was variable at a third site and not significantly correlated with changing sea-level,
where it is likely that forces other than change in relative sea-level are predominant. Currently, 16.5%, 23.4%, and 68.0%
of the three mangroves' landward margins are obstructed by coastal development from natural landward migration. The three
mangroves could experience as high as a 50.0% reduction in area by the year 2100. A 12% reduction in mangrove area by the
year 2100 is possible in the Pacific islands region. 相似文献
995.
M. Capobianco M. J. F. Stive J. A. Jiménez A. Sanchez-Arcilla 《Journal of Coastal Conservation》1998,4(1):7-16
Global climatic change is likely to take place and could eventually affect Mediterranean deltas and other lowlying coastal
regions. This would have serious implications for the natural resources of these deltaic areas, as well as for human settlements
and related economic activities.
To achieve sound decision making, to prevent damages and to avoid risky investments, it is necessary to understand the integral
functioning of deltaic areas and to determine their vulnerability and response to large-scale change phenomena. Optimal use
of the available knowledge will require that existing and new field measurements are combined and that integrated (physical/ecological)
conceptual models of deltaic behaviour are developed with socio-economics scenarios as boundary conditions.
This paper illustrates the methodological effort towards organizing a modeling framework to conduct budget computations at
various scales with reference to the most significant ‘physiogrpahic units’ and to the most significant deltaic processes.
The final objective is to handle the problem of evaluating possible changes under different scenarios. 相似文献
996.
Sea surface colour data, derived from the Coastal Zone Colour Scanner (CZCS) archive, have been used to assess the space/time
variability of coastal plumes and run-off in the Mediterranean Sea. A time series of 2645 scenes, collected by the CZCS from
1979 to 1985, was processed to apply sensor calibration algorithms, correct for atmospheric contamination, and derive chlorophyll-like
pigment concentration. Individual images, remapped on a 1-km2 pixel grid, were generated for each available day, and then mean values calculated pixel by pixel to form monthly, seasonal
and annual composites. The results obtained must be taken with caution, due to the CZCS limitations in the quantitative assessment
of bio-optical pigments when high concentrations of dissolved organics or suspended sediments are present, e.g. along littorals
or within plumes. Marked differences appear in the distribution of water constituents between coastal zones and open sea,
northern and southern near-coastal areas, western and eastern sub-basins. The oligotrophic character of the basin contrasts
with areas of high concentration related to river plumes—Ebro (Ebre), Po, Rhone, Nile—, coastal run-off patterns, and persistent
mesoscale features (e.g. coastal filaments and eddies). Seasonal variability appears to be high, with higher concentrations
occurring over most of the basin in the cold season, when climatic conditions are favourable to coastal run-off and vertical
mixing. Atmospheric forcing (wind and rainfall over continental margins) could play an important role in establishing the
observed space/time distribution of water constituents. The impact of continental interactions (fluvial and coastal run-off),
or that of exchanges between coastal zone and open sea, could have paramount influence on the biogeochemical fluxes in the
entire basin. 相似文献
997.
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
998.
微生物强化修复盐渍化石油污染土壤研究* 总被引:2,自引:0,他引:2
采集东营地区石油污染土壤,进行微生物修复实验研究。考察投加复合菌株CM-13是否能够加速生物修复进程以及土壤中石油污染物质降解的影响因素。石油污染土壤经过90 d的处理,在含水量一定的前提下,复合菌株CM-13对于石油污染物质的加速降解作用显著,当复合菌株CM-13接种量为土壤质量的10%时修复效果较好。微生物的生长与营养盐的量存在最佳匹配值,土壤中氮的最佳含量为0.20%,磷的最佳含量为0.05%。实验中随着麦糠投加量的增大,石油类的降解率逐渐增大,当麦糠量为土壤体积分数的25%时,对土壤的修复效果最好。 相似文献
999.
Michael G. Dosskey Zeyuan Qiu 《Journal of the American Water Resources Association》2011,47(4):662-671
Dosskey, Michael G. and Zeyuan Qiu, 2011. Comparison of Indexes for Prioritizing Placement of Water Quality Buffers in Agricultural Watersheds. Journal of the American Water Resources Association (JAWRA) 47(4):662‐671. DOI: 10.1111/j.1752‐1688.2011.00532.x Abstract: Five physically based, spatially distributed, empirical indexes were compared for the degree to which they identified the same or different locations in watersheds where vegetative buffers would function better for reducing agricultural nonpoint source pollution. All five indexes were calculated on a 10 m × 10 m digital elevation grid on agricultural land in the 144‐km2 Neshanic River watershed in New Jersey. The indexes included the topography‐based Wetness Index (WI) and Topographic Index (TI) and three soil survey‐based indexes (sediment trapping efficiency [STE], water trapping efficiency [WTE], and groundwater interaction [GI]). Results showed that each index associated higher pollution risk and mitigation potential to a different part of the landscape. The WI and TI identified swales and riparian areas where runoff converges, whereas STE and WTE identified upland sites. The STE and WTE lack the fine scale of slope resolution and the accounting for convergent runoff patterns that can be important for properly locating buffers in some watersheds. The GI index indicates the existence of a shallow water table but the correspondence with WI‐ and TI‐identified sites was only modest. For watersheds where pollutant loading is generated by both saturation‐excess (emphasized by TI and WI) and infiltration‐excess processes (emphasized by STE and WTE), the indexes could be complementary. However, techniques would be needed for properly apportioning priority among sites identified by each index. 相似文献
1000.
Russell Richards Milani ChaloupkaMarcello Sanò Rodger Tomlinson 《Ecological modelling》2011,222(19):3559-3567
We present here a copper speciation model that accounts for the long-term (‘coastal-acidification’) and short-term (daily and seasonal variation) variability in water pH and water temperature. The developed model is applied to a sub-tropical estuary (Moreton Bay, Australia) at a one hundred year time scale so that outputs are consistent with climate change projections. The model predicts that the mean cupric ion concentration (Cu2+) in the estuary will increase by 115% over the next 100 years as a result of the projected decrease in pH and increase in water temperature. Through calibration, the estimated concentration of copper-complexing dissolved organic matter (DOM) in the estuary is found to be 22.5 nM. An increase in the concentration of Cu2+, which is the most toxic and bioavailable form of copper, has implications for ecosystem health and may have a negative effect on the detoxifying capacity of DOM. Models that provide a framework for coupling biological, chemical and physical processes are important for providing a holistic perspective of coastal systems, especially for better understanding a system within the context of climatic and non-climatic drivers. 相似文献