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151.
This paper examines a 3-yr EU LIFE-funded project for the management of two especially protected areas on the Maltese coast. Project partners are the Euro-Mediterranean Centre on Insular Coastal Dynamics (ICoD), the Gaia Foundation and the Ministry for the Environment of Malta. Project sites are the Ghajn Tuffieha area on the northwest coast of Malta, and the Ramla Bay area on the island of Gozo. While both sites are in a relatively pristine state and comprise a number of features of ecological and scientific importance, they are also prime recreational areas, hosting thousands of visitors especially during the summer months. The challenge is to manage these sites in a sustainable manner in order to protect their unique ecology while simultaneously controlling and managing the human activities taking place there. The following sequence of activities is being implemented at both sites: surveys of the resources present (biodiversity, habitats, geological and hydrological features, and archaeological heritage), implementation of first intervention measures, and the drawing up and implementation of site-specific management plans, including rehabilitation and protection of biodiversity and habitats, regulations for site use, and awareness raising and educational measures. The management structure of this project supports the concept of decentralization of management of protected areas, through the granting of responsibility for the direct management of these sites to a non-governmental organization, under joint government/EU funding. This paper thus presents the project as a model for similar initiatives for the management of protected sites in the Mediterranean.  相似文献   
152.
    
Genetic diversity within species represents a fundamental yet underappreciated level of biodiversity. Because genetic diversity can indicate species resilience to changing climate, its measurement is relevant to many national and global conservation policy targets. Many studies produce large amounts of genome-scale genetic diversity data for wild populations, but most (87%) do not include the associated spatial and temporal metadata necessary for them to be reused in monitoring programs or for acknowledging the sovereignty of nations or Indigenous peoples. We undertook a distributed datathon to quantify the availability of these missing metadata and to test the hypothesis that their availability decays with time. We also worked to remediate missing metadata by extracting them from associated published papers, online repositories, and direct communication with authors. Starting with 848 candidate genomic data sets (reduced representation and whole genome) from the International Nucleotide Sequence Database Collaboration, we determined that 561 contained mostly samples from wild populations. We successfully restored spatiotemporal metadata for 78% of these 561 data sets (n = 440 data sets with data on 45,105 individuals from 762 species in 17 phyla). Examining papers and online repositories was much more fruitful than contacting 351 authors, who replied to our email requests 45% of the time. Overall, 23% of our email queries to authors unearthed useful metadata. The probability of retrieving spatiotemporal metadata declined significantly as age of the data set increased. There was a 13.5% yearly decrease in metadata associated with published papers or online repositories and up to a 22% yearly decrease in metadata that were only available from authors. This rapid decay in metadata availability, mirrored in studies of other types of biological data, should motivate swift updates to data-sharing policies and researcher practices to ensure that the valuable context provided by metadata is not lost to conservation science forever.  相似文献   
153.
Copepod nauplii are important in plankton food web dynamics, but limited information is available about their ecology due to methodological challenges. Reported here is a new molecular method that was developed, optimized, and tested in laboratory and field samples that uses quantitative PCR (qPCR) to identify and estimate the abundance of nauplii of the planktonic copepod, Parvocalanus crassirostris. The overall approach included collection of bulk zooplankton samples in the field, size fractionation to create artificial cohorts of relatively few developmental stages, obtaining DNA copy number for each size fraction by qPCR amplification of a target gene region, and estimation of the number of animals in each fraction through application of known DNA copy number across developmental stage. Method validation studies found that our qPCR-based approach has comparable accuracy to microscope-based counts of early developmental stages. Naupliar abundance estimates obtained using the two methods on cultured populations were similar; the regression of qPCR estimates on microscope-based counts resulted in a nearly 1:1 ratio (slope = 1.09). The qPCR-based method is superior to traditional identification and quantification methods for nauplii due to its higher taxonomic resolution, sensitive detection over a range of DNA quantities, and relatively high throughput sample processing.  相似文献   
154.
    
Growing human use of the marine environment increases the proximity of humans to marine wildlife and thus likely increases human–wildlife interactions. Such interactions influence perceptions of nature and promote or undermine conservation. Despite their importance, human–wildlife interactions are rarely considered in ecosystem-based marine spatial planning (MSP). Ideally, these interactions should be identified and considered in ecosystem-based management (EBM), which is often purported to be the basis for MSP. We used Marxan software and data from a citizen science project documenting location, species, age, sex, and activity type to identify regions along Israel's coast with a high probability of encounters between people and 2 species of guitarfish. We considered the geographic distribution of these encounters and the various activities undertaken by the reporting observers. We ran 4 scenarios in Marxan. Two had conservation goals of 30% and 50% guitarfish habitat protection. In the third and fourth scenarios, we added a 50% conservation goal of human leisure activities to each guitarfish conservation goal. We also conducted a gap analysis between our guitarfish conservation goals and the Israel Nature and Parks Authority's master plan for marine protected areas. We found the park authority was close to meeting the 30% goal but was far from meeting the conservation goal of 50% of guitarfish habitat conservation. Different human uses were more likely to interact with different life stages of guitarfish, and different recreational activities occurred in different areas. Identifying areas of specific human use showed which activities should be addressed in conservation management decisions. Our addition of certain recreational uses to the model of habitat conservation showed how enhancing human dimensions in conservation planning can lead to more holistic ecosystem-based conservation necessary for effective marine planning.  相似文献   
155.
    
The cascading effects of biodiversity loss on ecosystem functioning of forests have become more apparent. However, how edge effects shape these processes has yet to be established. We assessed how edge effects alter arthropod populations and the strength of any resultant trophic cascades on herbivory rate in tropical forests of Brazil. We established 7 paired forest edge and interior sites. Each site had a vertebrate-exclosure, procedural (exclosure framework with open walls), and control plot (total 42 plots). Forest patches were surrounded by pasture. Understory arthropods and leaf damage were sampled every 4 weeks for 11 months. We used path analysis to determine the strength of trophic cascades in the interior and edge sites. In forest interior exclosures, abundance of predaceous and herbivorous arthropods increased by 326% and 180%, respectively, compared with control plots, and there were significant cascading effects on herbivory. Edge-dwelling invertebrates responded weakly to exclusion and there was no evidence of trophic cascade. Our results suggest that the vertebrate community at forest edges controls invertebrate densities to a lesser extent than it does in the interior. Edge areas can support vertebrate communities with a smaller contingent of insectivores. This allows arthropods to flourish and indirectly accounts for higher levels of plant damage at these sites. Increased herbivory rates may have important consequences for floristic community composition and primary productivity, as well as cascading effects on nutrient cycling. By interspersing natural forest patches with agroforests, instead of pasture, abiotic edge effects can be softened and prevented from penetrating deep into the forest. This would ensure a greater proportion of forest remains habitable for sensitive species and could help retain ecosystem functions in edge zones.  相似文献   
156.
Ambio - Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most...  相似文献   
157.
In 1997, the U.S. Environmental Protection Agency revised the National Ambient Air Quality Standard governing ozone (O3), adding an 8-hr standard of 0.08 ppm and phasing out the 1-hr requirement of 0.12 ppm. The 8-hr standard is intended to provide greater protection for human health. This research examines spatial and temporal patterns of exceedances of the standards using monitoring data and modeled estimates. The Penn State/National Center for Atmospheric Research Mesoscale Model and Models-3 framework were used to estimate hourly O3 concentrations for 4-km resolution in the Maryland/Virginia/Delaware/Washington, DC, and northern Georgia domains. Results reveal that the spatial and temporal nature of compliance is considerably different under the 8-hr standard. In the modeling simulations, the 8-hr standard was exceeded 2-5.2 times more often and in a 1.8-16.2 times larger area than the 1-hr standard. The 8-hr standard was exceeded in areas that generally comply with the 1-hr standard and are not well covered by the monitoring network. These results imply that a larger population resides in areas with unhealthy O3 levels than noncompliance with the original 1-hr standard suggests. For the MD/VA/DE/DC domains, 80 and 98% of the total population live in areas with 8-hr National Ambient Air Quality Standards (NAAQS) exceedances for the 1990 and 1995 episodes, respectively.  相似文献   
158.
Physical changes that occur on the surface of fired shots due to firing and impact with soil may increase the dissolution of muniton metals. Increased metal dissolution could potentially increase metal transport and leaching, affecting metal concentrations in surface and groundwater. This research describes the relationship between the surface changes on fired tungsten-nickel-iron (94% W:2% Ni:4% Fe) composite shots and metals leaching from those shots. Tungsten composite shot was fired into, and aged in, three soil types (Silty Sand, Sandy Clay, and Silt) in mesoscale rainfall lysimeters to simulate live-fire conditions and subsequent interactions between the metals of the composite and soil. Leachate, runoff, and soil samples were collected from the lysimeters and analyzed for metal content. The shots were analyzed using scanning electron microscopy (SEM) to evaluate surface changes. SEM results indicated that a soil’s particle size distribution initially affected the amount of metal that was sheared from the surface of the fired W-composite shots. Shearing was greatest in soils with larger soil particles (sand and gravel); shearing was least in soils composed of small soil particles (fines). Increased metallic shearing from the shot’s surface was associated with increased W dissolution, compared to controls, following a simulated 1 year soil aging.  相似文献   
159.
Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.  相似文献   
160.
Fecal deposits by grazing animals on pasturelands have the potential to leach nutrients to runoff during rainfall events. Unlike croplands, grazing systems such as pasturelands or rangelands have little opportunity to ameliorate nutrient runoff through in-field or edge-of-field management practices. Thus, we investigated the amounts and concentrations of nutrients in overland flow from simulated grazing lands. Two grazing management scenarios were simulated: continuous grazing represented by two sparsely vegetated (SV) plots and rotational grazing represented by two densely vegetated (DV) plots. In addition, there were two control plots. The plots were treated with standard cowpats and rainfall was simulated until overland flow at the edge of the plots reached steady-state. Higher runoff was observed from DV plots (9.97 mm) than SV plots (7.05 mm), but the average total suspended solids concentration in runoff from SV plots was approximately 17 times the concentration observed in runoff from the DV plots. The average total phosphorus (TP) concentrations were highest in plots simulating continuous grazing (5.91 mg L(-1)). In both DV and SV plots at least 83% of the TP was found to be in the dissolved form. The average total Kjeldhal nitrogen (TKN) and total nitrogen concentrations observed in runoff samples from SV plots were 1.25 and 1.46 mg L(-1), respectively. Organic nitrogen comprised 95% of the TKN observed in runoff samples from SV plots. The SV plots have relatively higher loads for those nutrients in the particle associated form compared to DV plots, whereas DV plots had higher loads for those nutrients in the dissolved form. Grazing lands without any additional manure applications were found to release nutrients in high levels and vegetation did not show any effect on removing dissolved nutrients from runoff. These results are useful to inform selection of appropriate management practices to reduce nutrient transport to surface waters in watersheds dominated by grazed lands.  相似文献   
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