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1.
威海典型海滩沉积地貌及质量评价   总被引:1,自引:0,他引:1  
选择威海双岛湾附近海滩、国际海水浴场海滩、金海滩、青叽岛以西海滩、青叽岛以东海滩、天鹅湖海滩、桑沟湾海滩、楮岛海滩、南海新区海滩和乳山银滩十处代表性岸滩进行了海滩地貌和底质调查,结合沙滩表层样品分析测试数据,对研究区海滩地貌、沉积物粒度分布特征及海滩质量进行了综合评价。结果表明:威海海滩沉积物主要包括砾砂、粗砂、中砂、细砂四种类型,其中中砂分布最广,约占所有点位的35.6%,细砂、粗砂、砾砂分别占34.4%,26.7% 和3.3%。岸滩坡度一般较缓,宽度中等以上,岸滩质量整体较好,部分岸滩受沉积物粒度影响,质量稍差。  相似文献   

2.
Recreational beaches are strategic ecosystems for tourism and should be used in a sustainable manner. We studied three beaches in the municipality of Guaymas (NW Mexico), in order to assess their beach quality and identify key management issues. The evaluation was based on the perceptions of users concerning: (1) the user profile; (2) the recreational habits of users; and (3) the biophysical characteristics, infrastructure, services, and cleanliness of each beach. The results showed that the beaches were of different quality. The key management issues identified were the need to design and apply specific management programs for each beach, specifically in regards to improving infrastructure and services, and obtaining certification as a sustainable beach. The evaluation of the beaches as perceived by users suggests that it would be useful to assess beach quality in order to support management goals and be applicable to other beaches, both nationally and internationally.  相似文献   

3.
Recreational beach use with off-road vehicles is popular, but potentially harmful from an environmental perspective. Beaches are important habitats to invertebrates such as ghost crabs of the genus Ocyopde, which excavate extensive and elaborate burrows. Ghost crabs are sensitive to human pressures and changes in burrow architecture may thus be a consequence of disturbance by vehicles—the predictive hypothesis of this article. This was tested during the austral spring and summer by comparing 305 burrow casts between beaches open and closed to vehicles in Eastern Australia. Traffic influenced burrow architecture: there were smaller crabs on vehicle-impacted beaches, and after the peak traffic period (Christmas and New Year holidays), these crabs had tunnelled deeper into the sediment on shores rutted by cars. Crabs constructed all types of previously described burrows, but, significantly, smaller crabs from vehicle-impacted beaches simplified their shapes following heavy traffic disturbance from four (I, J, Y, M) to only two types (I, Y). These data support a model of active behavioural responses to disturbance from vehicles, extending the known effects of beach traffic to impacts on behavioural traits of the beach fauna.  相似文献   

4.
Sandy beaches are the prime sites for human recreation and underpin many coastal economies and developments. In many coastal areas worldwide, beach recreation relies on the use of off-road vehicles (ORVs) driven on the shore. Yet, the use of ORVs is not universally embraced due to social conflicts with other beach user groups and putative environmental consequences of vehicle traffic on sandy shores. Such ecological impacts of ORVs are, however, poorly understood for endobenthic invertebrates of the intertidal zone seawards of the dunes. Consequently, this study quantified the degree to which assemblages of intertidal beach invertebrates are affected by traffic. The study design comprised a series of temporally replicated spatial contrasts between two reference sites (no ORVs) and two beaches with heavy ORV traffic (in excess of 250,000 vehicles per year) located in South-East Queensland, Australia. Macrobenthic assemblages on ORV-impacted beaches had significantly fewer species at substantially reduced densities, resulting in marked shifts in community composition and structure. These shifts were particularly strong on the middle and upper shore where vehicle traffic was concentrated. Strong effects of ORVs were detectable in all seasons, but increased towards the summer months as a result of heavier traffic volumes. This study provides clear evidence that ORVs can have substantial impacts on sandy beach invertebrates that are manifested throughout the whole community. Demonstrating such an ecological impact caused by a single type of human use poses a formidable challenge to management, which needs to develop multi-faceted approaches to balance environmental, social, cultural, and economic arguments in the use of sandy shores, including management of “beach traffic.”  相似文献   

5.
The Missouri Department of Natural Resources (MDNR) has closed or posted advisories at public beaches at Lake of the Ozarks State Park in Missouri because of Escherichia coli (E. coli) concentration exceedances in recent years. Spatial and temporal patterns of E. coli concentrations, microbial source tracking, novel sampling techniques, and beach‐use patterns were studied during the 2012 recreational season to identify possible sources, origins, and occurrence of E. coli contamination at Grand Glaize Beach (GGB). Results indicate an important source of E. coli contamination at GGB was E. coli released into the water column by bathers resuspending avian‐contaminated sediments, especially during high‐use days early in the recreational season. Escherichia coli concentrations in water, sediment, and resuspended sediment samples all decreased throughout the recreational season likely because of decreasing lake levels resulting in sampling locations receding away from the initial spring shoreline as well as natural decay and physical transport out of the cove. Weekly MDNR beach monitoring, based solely on E. coli concentrations, at GGB during this study inaccurately predicted E. coli exceedances, especially on weekends and holidays. Interestingly, E. coli of human origin were measured at concentrations indicative of raw sewage in runoff from an excavation of a nearby abandoned septic tank that had not been used for nearly two years.  相似文献   

6.
Located on the northeast Brazilian coast, Olinda is one of UNESCO’s World Heritage Sites, which is economically dependent on tourism, commerce, industry, and the informal economy. Despite its environmental and socioeconomic importance, the city of Olinda (understanding the coast as part of it) has suffered several environmental and human disturbances over the last decades. This work describes the environmental and social status of Olinda’s beaches and makes recommendations concerning the development of an Integrated Coastal Management Plan for this coastal zone of the Brazilian littoral. The methodology adopted in this study is based on field campaigns (social, physical, chemical, and biological data collection), local observations, and the collection of sea contention building project data from city hall. The results showed that along the seven studied beaches, the main problems were related to the: (i) building of coastal protections, (ii) inefficient sewage disposal systems, (iii) inefficient urban management, and (iv) natural events (equinoctial spring tides and precipitation/evaporation rates). Casa Caiada beach showed the best hydrologic conditions as a consequence of its morphology and it presents facilities that attract housing and recreation investments (by private and public sectors) valuing and improving local use conditions. The obtained data showed that the studied beaches need an urgent action plan to minimize the environmental degradation of Olinda’s littoral and to promote sustainable development of the local coastal environments.  相似文献   

7.
Canada's National Agri-Environmental Standards Initiative sought to develop an environmental benchmark for low-level waterborne pathogen occurrence in agricultural watersheds. A field study collected 902 water samples from 27 sites in four intensive agricultural watersheds across Canada from 2005 to 2007. Four of the sites were selected as reference sites away from livestock and human fecal pollution sources in each watershed. Water samples were analyzed for Campylobacter spp., Salmonella spp., Escherichia coli O157:H7, Cryptosporidium spp., Giardia spp., and the water quality indicator E. coli. The annual mean number of pathogen species was higher at agricultural sites (1.54 ± 0.07 species per water sample) than at reference sites (0.75 ± 0.14 species per water sample). The annual mean concentration of E. coli was also higher at agricultural sites (491 ± 96 colony-forming units [cfu] 100 mL(-1)) than at reference sites (53 ± 18 cfu 100 mL(-1)). The feasibility of adopting existing E. coli water quality guideline values as an environmental benchmark was assessed, but waterborne pathogens were detected at agricultural sites in 80% of water samples with low E. coli concentrations (<100 cfu 100 mL(-1)). Instead, an approach was developed based on using the natural background occurrence of pathogens at reference sites in agricultural watersheds to derive provisional environmental benchmarks for pathogens at agricultural sites. The environmental benchmarks that were derived were found to represent E. coli values lower than geometric mean values typically found in recreational water quality guidelines. Additional research is needed to investigate environmental benchmarks for waterborne pathogens within the context of the "One World, One Health" perspective for protecting human, domestic animal, and wildlife health.  相似文献   

8.
The impact of river outfalls on beach water quality depends on numerous interacting factors. The delivery of contaminants by multiple creeks greatly complicates understanding of the source contributions, especially when pollution might originate up- or down-coast of beaches. We studied two beaches along Lake Michigan that are located between two creek outfalls to determine the hydrometeorologic factors influencing near-shore microbiologic water quality and the relative impact of the creeks. The creeks continuously delivered water with high concentrations of Escherichia coli to Lake Michigan, and the direction of transport of these bacteria was affected by current direction. Current direction reversals were associated with elevated E. coli concentrations at Central Avenue beach. Rainfall, barometric pressure, wave height, wave period, and creek specific conductance were significantly related to E. coli concentration at the beaches and were the parameters used in predictive models that best described E. coli variation at the two beaches. Multiple inputs to numerous beaches complicates the analysis and understanding of the relative relationship of sources but affords opportunities for showing how these complex creek inputs might interact to yield collective or individual effects on beach water quality.  相似文献   

9.
A composite index, based on function analysis and including thirteen sub-indices, was developed to assess the overall quality of urban and urbanized beaches in the Mediterranean area. The aggregation of components and sub-indices was based on two questionnaires completed by beach users and experts. Applying the new Beach Quality Index (BQI) demonstrated that the quality of beaches could be improved. In general, the strongest aspects of the beaches assessed were those related to short-term user demand, and the weakest were those related to the consequences of human pressure on the area, in particular, erosion problems. The composite index is intended to be used together with Environmental Management Beach Systems (EMBs) as a hierarchical management scorecard and in monitoring programs. This new tool could also make planning more proactive by synthesizing the state of the most important beach processes.  相似文献   

10.
11.
The horizontal, fluorophore enhanced, rep-PCR (HFERP) DNA fingerprinting technique was used to identify potential sources of in water, nearshore sand, and sediment at two beaches in the Duluth-Superior Harbor, near Duluth, MN, and Superior, WI, during May, July, and September 2006. An animal or environmental source could be identified for 35, 29, and 30% of strains in water, sand, and sediments, respectively. Waterfowl, including Canada geese, ring-billed gulls, and mallard ducks, were the largest source of that could be identified in water (55-100%), sand (59-100%), and sediment (92-100%) at both beaches. Although ring-billed gulls were more abundant in this harbor, Canada geese were usually the dominant source of waterfowl found at these beaches. The percentage of identified from treated wastewater was always less than the percentage of originating from waterfowl. At both beaches, the percentage of in water contributed by treated wastewater was higher in May compared with July and September. The larger proportion of wastewater-derived seen in May probably reflected a smaller contribution of from geese when these birds were less abundant rather than an absolute increase in from treated wastewater. Microbial source analysis and bird census data both indicated that waterfowl were a major source of at beaches in the Duluth-Superior Harbor. These data also indicated it is risky to assume that the most abundant waterfowl species present in waterways will also be the largest source of avian-derived in water, nearshore sand, and sediments at beaches.  相似文献   

12.
Reestablishing Naturally Functioning Dunes on Developed Coasts   总被引:2,自引:0,他引:2  
Common beach management practices reduce the ecological values of coastal dunes. Mechanical beach cleaning eliminates incipient dunes, habitat for nesting birds, seed sources for pioneer dune colonizers and food for fauna, and artificially small, stabilized foredunes reduce the variability in microenvironments necessary for biodiversity. Recent initiatives for reducing coastal hazards, protecting nesting birds, and encouraging nature-based tourism provide incentive for the development of a restoration program for beaches and dunes that is compatible with human use. Suggested changes in management practice include restricting or rerouting pedestrian traffic, altering beach-cleaning procedures, using symbolic fences to allow for aeolian transport while preventing trampling of dunes, and eliminating or severely restricting exotic species. Landforms will be more natural in function and appearance but will be more dynamic, smaller and in a different position from those in natural areas. Research needs are specified for ecological, geomorphological, and attitudinal studies to support and inform restoration planning.  相似文献   

13.
Microbial biodegradation of polycyclic aromatic hydrocarbons (PAHs) during the process of bioremediation can be constrained by lack of nutrients, low bioavailability of the contaminants, or scarcity of PAH-biodegrading microorganisms. This study focused on addressing the limitation of nutrient availability for PAH biodegradation in oil-contaminated beach sediments. In our previous study, three nutrient sources including inorganic soluble nutrients, the slow-release fertilizer Osmocote (Os; Scotts, Marysville, OH) and Inipol EAP-22 (Ip; ATOFINA Chemicals, Philadelphia, PA), as well as their combinations, were applied to beach sediments contaminated with an Arabian light crude oil. Osmocote was the most effective nutrient source for aliphatic biodegradation. This study presents data on PAH biodegradation in the oil-spiked beach sediments amended with the three nutrients. Biodegradation of total target PAHs (two- to six-ring) in all treatments followed a first-order biodegradation model. The biodegradation rates of total target PAHs in the sediments treated with Os were significantly higher than those without. On Day 45, approximately 9.3% of total target PAHs remained in the sediments amended with Os alone, significantly lower than the 54.2 to 58.0% remaining in sediment treatments without Os. Amendment with Inipol or soluble nutrients alone, or in combination, did not stimulate biodegradation rates of PAHs with a ring number higher than 2. The slow-release fertilizer (Os) is therefore recommended as an effective nutrient amendment for intrinsic biodegradation of PAHs in oil-contaminated beach sediments.  相似文献   

14.
Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far‐reaching consequences within aquatic ecosystems.  相似文献   

15.
Fecal bacteria have traditionally been used as indicator organisms to monitor the quality of recreational waters. Recent work has questioned the robustness of traditional indicators, particularly at seawater bathing beaches. For example, a study of Florida beaches found unexpectedly high abundances of Escherichia coli, fecal coliforms, and enterococci in beach sand. The aim of the present study was to explain these abundances by assessing the survival of E. coli and enterococci in beach sand relative to seawater. We used a combination of quantitative laboratory mesocosm experiments and field observations. Results suggested that E. coli and enterococci exhibited increased survivability and growth in sand relative to seawater. Because fecal bacteria are capable of replicating in sand, at least under controlled laboratory conditions, the results suggest that sand may be an important reservoir of metabolically active fecal organisms. Experiments with "natural" mesocosms (i.e., unsterilized sand or water rich in micropredators and native bacteria) failed to show the same increases in fecal indicators as was found in sterile sand. It is postulated that this was due to predation and competition with indigenous bacteria in these "natural" systems. Nonetheless, high populations of indicators were maintained and recovered from sand over the duration of the experiment as opposed to the die-off noted in water. Indicator bacteria may wash out of sand into shoreline waters during weather and tidal events, thereby decreasing the effectiveness of these indicators as predictors of health risk and complicating the interpretations for water quality managers.  相似文献   

16.
Human actions can contribute to degradation of coastal environments or they can increase the likelihood that these environments will be restored. Beach nourishment provides a basis for restoration, but ways must be found to add habitat improvement to projects designed for shore protection. This study examines how beach nourishment projects can help reinstate dune landscapes in locations where beaches and dunes had been replaced by static shore protection structures. Dune topography and vegetation on three nourished sites on the northern Adriatic Coast of Italy are compared to a reference site to evaluate changes after beach fill was emplaced. Results reveal how nourishment projects used for shore protection can restore the space available for dunes to form, increase the likelihood of sediment transfers inland and increase the diversity of topography and vegetation. Beach raking prevents formation and growth of hummocky, incipient backshore dunes that would otherwise evolve into a naturally functioning foredune. Sand-trapping fences can speed the process of foredune development but can be counterproductive if they interfere with transport to beach grass (Ammophila littoralis) planted landward of them. Shore protection structures can provide stability and more time for dune evolution on eroding shores, resulting in greater species richness and longer retention of ecological niches. These structures need not be required if re-nourishment occurs frequently enough to provide a beach wide enough to protect against storm wave uprush.  相似文献   

17.
Sea turtles have a high reproductive output and high mortality at early stages of the life cycle. In particular, many nests are laid below or close to high tide lines, and subsequently large numbers of eggs may be inundated and destroyed. A common conservation procedure is to relocate such doomed eggs to higher ground. This article examines this practice in the light of recent data revealing that some individual turtles tend to nest relatively near the water and others relatively higher up the beach. Discussion is focused on the question of why apparently poor placement of nests has not been selected against. Comparison between the ecology of leatherback and hawksbill turtle nesting beaches suggests that predictability of environmental conditions on the nesting beaches has an important influence on patterns of nest-site selection. Options are outlined for the management of nesting beaches where a high proportion of turtle eggs is subject to destruction by flooding. An erratum to this article is available at.  相似文献   

18.
ABSTRACT: Diseases in wild fish populations may have multiple economic and social impacts. Epidemics of infectious diseases, which are associated with the presence of some microbe or parasite, have recently been observed in several major estuarine systems in the eastern United States. The most prevalent of these problems is ulcerative mycosis (UM), a fungal infection. The agents responsible for UM and many of these other diseases are opportunistic pathogens that are not believed to infect normal, immunocompetent individuals. While inroads have been made into determining the infectious agents associated with these diseases, we know very little of how pollution may influence their prevalence. Understanding the importance of pollution requires an awareness of all the environmental conditions that can affect the health of wild populations. In this paper, a multistep examination of the interactions between the host, pathogen(s), and environment is outlined.  相似文献   

19.
We investigated the hypothesis that perception of psychological restorativeness during visits to coastal parks is modified by objective and perceived environmental conditions. Visitors (n = 1153) to California beaches completed a survey on perceived weather, environmental quality, and perceived restorativeness. We used generalized ordinal logistic models to estimate the association between environmental parameters and odds of perceiving higher levels of restorativeness. Visitors perceived greater restorativeness at beaches when ambient temperatures were at or below mean monthly temperatures and during low tides. The odds of perceiving the environment as more psychologically restorative were three times greater when visiting on days defined by government policy as having good air quality (OR = 3.25; CI: 1.69–6.28). Visitors’ perception of air (OR = 1.56; CI: 1.14–2.18) and water quality (OR = 1.78; CI: 1.28–2.49) also affected perceived restorativeness; with perceived healthy days more restorative. Warmer temperatures with less space due to sea level rise and poor environmental quality will restrict restorative experiences in recreational facilities designed for urban populations.  相似文献   

20.
An evaluation of coastal processes, shoreline erosion, and shore management options for Conference House Park, New York, USA, reveals the problems associated with lack of congruence between jurisdictional boundaries and boundaries required for maintenance of beaches and shorefront park land. Rates of shoreline change are high despite low wave energies because bay beaches contain small amounts of sand. The park is so narrow in places that the shoreline will soon move out of park boundaries. This condition will eliminate natural beach resources, restrict access, and create political and administrative problems. Management strategies include revetment construction, beach nourishment, and acquisition of additional land. Obtaining the maximum length of shorefront to create a park may be less cost effective in maintaining natural beach resources than obtaining a shorter frontage and more compact shape that allows for shoreline movement. The problems of managing eroding shorelines in urban estuaries are acute because space is lacking, the cost of land is high, and the critical nature of shoreline erosion is disguised by low wave energies and lack of daily beach change.  相似文献   

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