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A major obstacle for characterizing dissolved organic matter (DOM) with ultrahigh resolution mass spectrometry has been its low concentrations in natural waters. Many previous mass spectrometric studies of both terrestrial and marine DOM typically have isolated and concentrated the DOM using solid phase C18 extraction disks, ultrafiltration, or XAD resins, all of which are known to discriminate against many different classes of compounds. We have, for the first time, developed an approach to directly analyze natural water samples with less than 6 mg/l DOC (dissolved organic carbon), using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). We demonstrate the sensitivity and ability of sequential selective ion accumulation (SSIA) to detect the thousands of components in a single freshwater DOM sample without any significant pretreatment. By utilizing SSIA, the baseline noise decreases while signal to noise ratios of the peaks increase, allowing for approximately 40% more formulas to be assigned to peaks in the mass spectra. 相似文献
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José C. García‐Gómez Carlos M. López‐Fé Free Espinosa José M. Guerra‐García Georgina A. Rivera‐Ingraham 《Marine Ecology》2011,32(1):6-14
The installation of urban and commercial infrastructures on the coast has a severe impact on the marine environment. This impact is mostly negative but, simultaneously, some of the species that colonize artificial substrata (sometimes rare or threatened) find refuge in man‐made structures. The protection of endangered species is usually provided by marine protected areas or by laws that punish their damage or collection, but effective enclosure and custody must be achieved in the case of easily accessible intertidal species. We used the ferruginous limpet, Patella ferruginea, as a case study because it is the most endangered invertebrate in the Mediterranean. This species, which lives in the intertidal zone and is very accessible to people, is a free‐spawning, protandric hermaphrodite, highly dependent on population density and individual size for its reproductive success. Previous work by the authors found the species is especially abundant on artificial substrates on both shores of the Strait of Gibraltar, where people collect fewer of them. Spanish laws of coastal management do not allow the enclosure of the natural coastline, but artificial installations like harbour breakwaters may be closed or guarded, and visits for educational purposes may be carried out under control. The possibility of declaring some kind of environmental protection for these artificial areas would be a very helpful tool for conservation and management purposes. Protected individuals would grow larger and eventually produce exponentially more offspring, which could be transported by currents to adjacent habitats. Here we propose a protection concept for artificial sites termed Artificial Marine Micro‐Reserve (AMMR), where some endangered species experience a refuge from human disturbance. This concept is a modification of the land micro‐reserves that have been recently declared in small natural sites that keep rare plant species. A network of AMMRs would be the final objective, allowing the creation of a great metapopulation of P. ferruginea and also giving refuge to other endangered species that have been found to grow in this type of substratum. Critically, the declaration of a micro‐reserve cannot be used as a reason in favour of new construction because of the negative influence of such structures on the marine environment, together with the fact that there is no certainty that valuable species will settle on them. 相似文献
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Molecular diversity of phytoplankton in the East China Sea around Jeju Island (Korea), unraveled by pyrosequencing 总被引：1，自引：0，他引：1
Daphne Georgina Faria Man-Duck Lee Joon-Baek Lee Juyun Lee Man Chang Seok Hyun Youn Young Sang Suh Jang-Seu Ki 《Journal of Oceanography》2014,70(1):11-23
The East China Sea (ECS) around Jeju Island lies in a transitional region between the temperate and subtropical zones and is influenced by the Kuroshio Current. Hence, this area has been considered an important monitoring site for oceanic ecosystem changes. Herein, we assessed the community structure and diversity of the phytoplankton in the ECS around Jeju Island using small subunit ribosomal RNA pyrosequencing. We analyzed eight samples collected from the surface and at 30 m- and/or 50-m depths from two neritic and oceanic stations each from 24–30 April 2011. Comparisons of 15,498 pyrosequences identified 172 phylotypes of phytoplankton, excluding cyanobacteria, from the four surface stations. These pyrosequences were represented by dinoflagellates (29 %), stramenopiles (31 %), and chlorophytes (>39 %), with minor contributions from cryptophytes, haptophytes, and Telonemia. Phylotypes retrieved at 30- and 50-m depths were very similar to the surface samples. However, phylotype diversity and community structure varied considerably with the stations. Dominant phylotypes included Karlodinium veneficum, Ostreococcus tauri, Skeletonema marinoi, and Thalassiosira curviseriata, and many of the detected phylotypes include new records for the present study area. This study provides a valuable phylotype reference for future phytoplankton community structure and diversity studies with regard to marine environmental changes. 相似文献
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Jessica Cockburn Georgina Cundill Sheona Shackleton Ayanda Cele Susanna Francina Cornelius Vaughan Koopman 《社会与自然资源》2020,33(5):681-693
AbstractLandscape stewardship is considered an important place-based approach to addressing sustainability challenges. Working at landscape-level requires collaboration between diverse landscape stakeholders. In this study, we partnered with local stewardship practitioners across six cases in South Africa to investigate how they facilitate collaboration towards social-ecological sustainability outcomes. We found that practitioners facilitate collaboration among stakeholders by operating as relational hubs in the landscape. Through these hubs, they build new inter-personal relationships among stakeholders, creating social networks which enable stewardship practice. The hubs deepen human-nature relationships by creating enabling conditions for stewards to put stewardship ethics into action. Drawing on insights from these cases, we call for a relational approach to landscape stewardship which focuses on human-to-human and human-to-nature relationships. Moreover, we argue that landscape stewardship initiatives need to re-focus stewardship on stewards, recognizing them as key agents of change in addressing the conflict between agriculture and conservation inherent in many landscapes. 相似文献
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Adapting agriculture to climate change: a review 总被引：2，自引：0，他引：2
Muhuddin Rajin Anwar De Li Liu Ian Macadam Georgina Kelly 《Theoretical and Applied Climatology》2013,113(1-2):225-245
The agricultural sector is highly vulnerable to future climate changes and climate variability, including increases in the incidence of extreme climate events. Changes in temperature and precipitation will result in changes in land and water regimes that will subsequently affect agricultural productivity. Given the gradual change of climate in the past, historically, farmers have adapted in an autonomous manner. However, with large and discrete climate change anticipated by the end of this century, planned and transformational changes will be needed. In light of these, the focus of this review is on farm-level and farmers responses to the challenges of climate change both spatially and over time. In this review of adapting agriculture to climate change, the nature, extent, and causes of climate change are analyzed and assessed. These provide the context for adapting agriculture to climate change. The review identifies the binding constraints to adaptation at the farm level. Four major priority areas are identified to relax these constraints, where new initiatives would be required, i.e., information generation and dissemination to enhance farm-level awareness, research and development (R&D) in agricultural technology, policy formulation that facilitates appropriate adaptation at the farm level, and strengthening partnerships among the relevant stakeholders. Forging partnerships among R&D providers, policy makers, extension agencies, and farmers would be at the heart of transformational adaptation to climate change at the farm level. In effecting this transformational change, sustained efforts would be needed for the attendant requirements of climate and weather forecasting and innovation, farmer’s training, and further research to improve the quality of information, invention, and application in agriculture. The investment required for these would be highly significant. The review suggests a sequenced approach through grouping research initiatives into short-term, medium-term, and long-term initiatives, with each initiative in one stage contributing to initiatives in a subsequent stage. The learning by doing inherent in such a process-oriented approach is a requirement owing to the many uncertainties associated with climate change. 相似文献
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Throughout much of the late eighteenth and early nineteenth centuries, the tropics and subtropics were constructed as a relatively homogenous realm. The supposed 'pathological potency' of these regions was assumed to render them particularly hazardous for European constitutions relative to 'temperate' locations. The interior of Africa represented one such apparently pestilential place. This paper examines how the experiences of nineteenth-century missionaries based at various stations in central southern Africa might have been influenced by popular and scientific debates focusing on environment, climate and health in Africa. We also illustrate how their perspectives may have challenged popular homogenized conceptualizations of interior Africa as a uniformly dangerous place for Europeans and helped to identify a spatially varied pathological geography of the region. 相似文献
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Functional diversity of fish and invertebrates in coral and rocky reefs of the Eastern Tropical Pacific 
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下载免费PDF全文 Georgina Ramírez‐Ortiz Luis E. Calderon‐Aguilera Hector Reyes‐Bonilla Arturo Ayala‐Bocos Luis Hernández Francisco Fernández Rivera‐Melo Andres López‐Pérez Arturo Dominici‐Arosamena 《Marine Ecology》2017,38(4)
To define the functional groups of fish and macroinvertebrates in the Eastern Tropical Pacific (ETP), visual censuses were performed in 18 areas of four biogeographic provinces: Cortés, Mexican, Panamic and Oceanic Islands. A total of 257 fish and macroinvertebrate species were recorded, and from them, 27 morpho‐functional groups (MFGs) were constructed on the basis of trophic level, maximum size, taxonomy and morphology. Biomass, richness, diversity and evenness of MFGs were calculated for each province and compared statistically; a regression analysis between taxonomic and functional diversity was conducted to observe the relationship between these two indicators. There were significant differences in all ecological indices (p < .002), highlighting the high biomass and richness of MFGs in the Cortés and Oceanic Islands provinces (>400 g/m2), associated with the influence of cold currents in the northernmost region and less fishing pressure in protected areas. A decreasing pattern of MFG richness towards the tropics was observed, which demonstrates that in the ETP, the relationship between habitat heterogeneity and species diversity has been translated into functional complexity. The Mexican province was the most functionally diverse (biomass well distributed in the MFG; H′ = 0.46 ± 0.009). Related to this, it is predicted that biomass is biased towards certain functional groups (i.e., large carnivores), which shows that the H′ index of the MFG is not a good indicator of the conservation status of ETP reefs. Finally, regression analysis suggests that functional diversity increases at low species diversity but eventually reaches an asymptote (almost all possible functions are represented). 相似文献