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181.
182.
大亚湾惠州岸段城市化发展与海岸带生态系统保护协调研究 总被引:1,自引:0,他引:1
在分析海岸带生态系统结构、功能特点的基础上,指出大亚湾惠州岸段可持续发展的途径就是实现经济开发与海岸带生态环境保护之间的协调发展,为此,提出了区域生态--经济系统综合效益表达工,并运用该表达式,从大亚湾海水环境保护的角度出发,得出了惠州大亚湾沿岸地区在1994年-2010年间工业发展的合理速度。 相似文献
183.
A. Jarernpornnipat O. Pedersen K. R. Jensen S. Boromthanarat S. Vongvisessomjai P. Choncheanchob 《Journal of Coastal Conservation》2003,9(2):135-146
Bandon Bay (Surat Thani Province) is one of the most productive coastal areas in southern Thailand. The Tapi River and 18
channels are the main sources of freshwater, nutrients, organic matter and sediment to the bay and the loading of freshwater
and nutrients provide essential support for the production of phytoplankton in the estuarine ecosystem. Bandon Bay is important
as natural spawning, nursery and feeding grounds for shellfish such as oysters, blood cockles, green mussels, short-necked
clams, mud crabs and shrimps, and the estuary also serves as an excellent area for mariculturing of shellfish. In fact, oysters
and blood cockles cultured in Bandon Bay are now being exported worldwide. However, Bandon Bay is also a textbook example
of overexploitation of coastal resources in the tropics including all the derived changes in the estuarial ecosystem with
severe socio-economic consequences. Hence, there is an urgent need for setting up an integrated management plant for a sustainable
use of shellfish resources in Bandon Bay. The present study attempts to integrate water quality simulation results, socio-economic
data and information on existing shellfish resource use in the process of proposing a set of sustainable management strategies
for shellfish resources in Bandon Bay. These strategies involve: (1) using water quality modeling to monitor ecological and
environmental changes in shellfish culture beds and their natural habitats in the process of setting up a master plan for
management of waste water discharge into Bandon Bay; (2) zoning of shellfish mariculture in the coastal area in order to solve
conflicts between resource users; (3) setting up a clear system for taxation of mariculture where the revenue may be used
for (4) setting up and managing mangrove strips as filters of pollution and sediment around Bandon Bay; and finally (5) it
is suggested to form a committee with members representing all relevant stakeholders plus the local government in order to
work on resolving the existing and potential future conflicts over resource usage in Bandon Bay. This methodology may be seen
as an important contribution towards a Bandon Bay sustainable management approach, based on the principles of integrated coastal
zone management because it is science-based and takes into consideration the needs and perceptions of people involved in coastal
resource extraction. 相似文献
184.
Limitations of Biodiversity Databases: Case Study on Seed-Plant Diversity in Tenerife, Canary Islands 总被引:3,自引:0,他引:3
Abstract: Databases on the distribution of species can be used to describe the geographic patterns of biodiversity. Nevertheless, they have limitations. We studied three of these limitations: (1) inadequacy of raw data to describe richness patterns due to sampling bias, (2) lack of survey effort assessment (and lack of exhaustiveness in compiling data about survey effort), and (3) lack of coverage of the geographic and environmental variations that affect the distribution of organisms. We used a biodiversity database (BIOTA-Canarias) to analyze richness data from a well-known group (seed plants) in an intensively surveyed area (Tenerife Island). Observed richness and survey effort were highly correlated. Species accumulation curves could not be used to determine survey effort because data digitalization was not exhaustive, so we identified well-sampled sites based on observed richness to sampling effort ratios. We also developed a predictive model based on the data from well-sampled sites and analyzed the origin of the geographic errors in the obtained extrapolation by means of a geographically constrained cross-validation. The spatial patterns of seed-plant species richness obtained from BIOTA-Canarias data were incomplete and biased. Therefore, some improvements are needed to use this database (and many others) in biodiversity studies. We propose a protocol that includes controls on data quality, improvements on data digitalization and survey design to improve data quality, and some alternative data analysis strategies that will provide a reliable picture of biodiversity patterns. 相似文献
185.
分析了沿海滩地3种框围养鱼方式(即精料、种草、化肥养鱼)的能量转换效率及种草养鱼的经济效益。初步得出:在沿海滩地低投入框围养鱼中应重视对太阳能的利用;种草养鱼在3种养鱼方式中能量转换效率最高,经济效益较佳,应推广种草养鱼技术,提高资源利用率。 相似文献
186.
Based on a phenomenology that is rather frequent in the Gulf of Trieste (Northern Adriatic Sea), we analytically model the short time evolution of the temperature field inside a shallow layer of coastal water induced by a sudden offshore wind. In particular, we reproduce in a very simple way the unsteady surfacing of the isotherms forced by the marine current circulating in a vertical plane perpendicular to the coastline. The model is in agreement with the observations of a significant event recorded on 25 June, 2002 in the Gulf of Trieste. 相似文献
187.
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189.
施加生物炭对河流沿岸土吸附铜的影响机制 总被引:1,自引:0,他引:1
为探究生物炭施加对河流沿岸土吸附铜的影响机制,采集嘉陵江流域(川渝段)内苍溪(CX)、南部(NB)、嘉陵(JL)和合川(HC)沿岸土表层(S,0~20 cm)、亚表层(D,20~40 cm)共8种土样,分别将1%(质量比)生物炭(B)加入到8种土样中形成混合土样(CX_(SB)、NB_(SB)、JL_(SB)和HC_(SB); CX_(DB)、NB_(DB)、JL_(DB)和HC_(DB))。以原始土样作为对照,批处理法研究各供试土样在不同温度、pH和离子强度下的Cu~(2+)吸附和热力学特征,并分析Cu的吸附形态。结果显示:(1)各供试土样对Cu~(2+)的等温吸附都适用Langmuir模型描述,Cu~(2+)的最大吸附量q_m在62. 20~363. 64 mmol/kg之间,S层土样对Cu~(2+)的吸附量均呈现JL NB CXHC的趋势,而D层土样呈现JL CX NB HC的趋势。施加生物炭有助于增强D层土壤对Cu~(2+)的吸附。(2) 20~40℃范围内,各供试土样对Cu~(2+)的吸附量均随温度的升高而升高,表现为增温正效应。热力学参数结果表明各混合土样对Cu~(2+)的吸附是一个自发、吸热和熵增的过程。(3) pH的升高有利于各供试土样对Cu~(2+)的吸附。随着离子强度的增加,各混合土样(HC_S和HC_D除外)对Cu~(2+)的吸附量均呈现先增后降的趋势,0. 1 mol/L时最大。(4)土样中吸附的铜主要以碳酸盐结合态和铁锰氧化物结合态铜存在,生物炭的施加增加了土样中可交换态(HC除外)和有机结合态铜含量,而对碳酸盐结合态和铁锰氧化物结合态铜影响较小。供试土样对Cu~(2+)的q_m主要是由CEC和比表面积决定的。 相似文献
190.