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111.
We quantified spatial dynamics and substrate impacts of snorkelers and SCUBA divers within four Hawaiian MPAs to determine:
(1) whether coral reefs in these areas are being damaged by recreational activities, and (2) how damage might be mitigated.
Observers secretly followed snorkelers and SCUBA divers, and used handheld Global Positioning System (GPS) units to record
their geographic tracks and substrate contacts. Most activities occurred within relatively small, well-defined areas associated
with access points. Despite heavy use, recreation impact was low at Hawaiian MPAs because most fragile corals occurred below
the maximum depth of the dominant recreational activity (snorkeling). SCUBA diving was only common at one MPA with physically
durable benthic habitats. GPS tracking provided useful insights into how recreational impacts to MPAs could be reduced. General
topography could be used to predict where visitors will go, and designated access points could be used to focus substrate
contact away from fragile habitats. 相似文献
112.
Influence of Social, Biophysical, and Managerial Conditions on Tourism Experiences Within the Great Barrier Reef World Heritage Area 总被引:1,自引:0,他引:1
N = 1475) traveling with tourism operations of different sizes who traveled to different sites completed surveys. Results indicated
that snorkelers who traveled with larger operations (more people and infrastructure) differed from those traveling with smaller
operations (few people and little on-site infrastructure) on benefits received and in the way that specific conditions influenced
their enjoyment. Benefits related to nature, escape, and family helped to define reef experiences. Conditions related to coral,
fish, and operator staff had a positive influence on the enjoyment of most visitors but, number of people on the trip and
site infrastructure may have the greatest potential as setting indicators. Data support the potential usefulness of visitor
input in applying the LAC concept to a marine environment where tourism and recreational uses are rapidly changing. 相似文献
113.
114.
两种铝盐处理纸浆CEH漂白废水的混凝特性的研究 总被引:2,自引:0,他引:2
运用Zeta电位测定技术研究了聚合铝PAC、聚硅铝PSA两种不同形态铝盐对漂白废水絮凝反应特性,通过絮凝过程中Zeta电位及傅立叶红外光谱对原水及两种铝盐沉淀物进行了分析,结果表明:吸附架桥为其反应的主要机理,两种铝盐与漂白废水中污染物之间反应均以铝的羟基化合物与漂白废水中氯化木素氢键缔合的形式相结合 相似文献