Local Environmental Dynamics Research Articles

Doing place through data: Proliferation, profiling and the perils of portrayal in local climate action

Building on work which has shown the role of digital technologies in reframing environmental relations, this paper explores ethnographically how environmental data is reconfiguring the concept of place. The paper takes as its focus an action-research project within a UK based, citizen-oriented initiative called Newtown Energy Futures, in which we sought to enfold climate and energy data into a social-justice informed attempt at climate action. By exploring how the project used data as an invitation for citizens to engage with and participate in local infrastructural and environmental dynamics, the paper sheds light on how environmental data came to participate in the making of place and in doing so raised questions about how to rebuild the socio-material relations through which ‘a sense of place’ might be reproduced. As climate and energy data increasingly demand that places become enrolled into environmental projects our findings suggest that data enables place to emerge as a ‘socio-technical potentiality’ an observation that has implications both for both engagement with, and the study of data and place. In practical terms, we suggest that this refiguration of place has the effect of creating hopeful trajectories for change, whilst also posing difficult questions about the limits of participation in a data-infused form of place-based politics.

Evaluation of the environmental sustainability of agricultural production using the methodologies of emergy analysis and life cycle assessment. Case study, tomato grown in Mendoza (Argentina)

This article evaluates the environmental performance of tomato production in Mendoza (Argentina) using two methodologies that share the same approach and part of the inventory: i) Life Cycle Analysis, a method that considers all flows (incoming and outgoing) involved in the life cycle of a product, and ii) Emergetic Analysis, which represents the environmental support provided directly and indirectly by the biosphere to economic processes in the form of resources and ecosystem services. The combined application of these two tools helps to identify critical points in the production system and to generate proposals for improvement and innovation. In this case, the critical points identified are irrigation and fertilizers. Specifically for the environmental category Climate change, crop irrigation represents 51 % of the total impact, while seedling production represents 22 %. The emergy analysis, without accounting for direct and indirect human labor, shows a low contribution of local natural resources to the final product (0.12 %), as well as an environmental burden of 7.23 %. The results show that the local environmental dynamics are altered because tomato production is mostly driven by external inputs, mainly fertilizers (especially nitrogenous fertilizers) and energy.

The evolution of the Maya coastal landscape in the Mexican Caribbean during the last 6200 years

The modern configuration of tropical coastlines is a result of changes in sea level and regional hydroclimates during the Holocene. In some regions, such as the Yucatan Peninsula, human occupation has also played an important role in defining coastal dynamics. We use a multiproxy analysis of a 6200-year-long sedimentary record from La Encantada lagoon, located near the Bay of Chetumal, Mexican Caribbean, to reconstruct local and regional environmental dynamics. By characterizing the record in terms of pollen and charcoal content, and geochemical composition, we aim to determine the relative importance of sea level rise, long term trends of moisture availability, and anthropic influences in the evolution of the Mayan coastal landscape. Our findings indicate a dominance of marine influences between ∼6200 and 5000 cal yr. BP, probably resulting from the rapidly rising sea level. During this time, whereas the water column was brackish, fluvial dynamics seem characterized by high erosion and the development of riparian mangroves. The geochemical record indicates a millennial-scale trend towards drier conditions, likely associated with the southward migration of the Intertropical Convergence Zone through the Holocene. This trend is also reflected in a progressive increase in the abundance of deciduous taxa in the vegetation. Centennial-scale climatic dynamics, on the other hand, seem associated with variability of the North Atlantic Subtropical High. Anthropogenic influence is evident around ∼5000 cal yr. BP, when local fires became more frequent and riparian mangroves were depleted. Taxa associated with human influence substantially increased at ∼3600 cal yr. BP, coinciding with an erosion increase indicated by the geochemical record. At ∼2200 cal yr. BP, anthropic disturbance indicators decrease, suggesting a potential role of modified agricultural practices to control soil erosion. The last ∼1000 years have been characterized by a decline of agricultural activity and a recovery of the riparian mangroves, suggesting modern vegetation is a result of forest recovery during the last millennium. Overall, our results show that sea level rise and changes in the regional hydroclimate modulate the evolution of the regional landscape, particularly through influences on the sedimentation rates. However, human occupation represents an overpowering influence that can modulate processes associated with natural forcings.

Indigenous institutions as adaptive measures to environmental dynamics: an ethnographic study of Loba Community of Upper Mustang, Nepal

This paper investigates how different institutions of Loba communities of the Upper Mustang work together and facilitate the community to cope with the environmental dynamics in the region. The indigenous institutions are place-based, and their evolution is concerned with reducing vulnerability and enhancing the resilience capacity of place-based communities to cope with and adapt to local natural and socio-cultural environmental dynamics. The paper is based on anthropological fieldwork. Qualitative data were collected by applying observation and interviews. The paper presents the role of the galbo, (Lo King), ghenba (Village Chief), Lama (Monk), and dhongba (Household) as local institutions that act in close relation and make community-level decisions. The findings reveal that the King is seen as the leader whose governance best suited to the local natural environment, cultural practices, and economy. The Lama plays a major role in reinforcing local rules, while the Ghenba is an agent who mediates the Lo King and people in materializing rules and operationalizing institutional mechanisms. The Dhongbas are units of production of the local social-ecosystem that are entitled to use local resources within the context of the institution’s agreed rules, norms, and values. These local institutions are cooperating well, successfully regulating, managing, and protecting agricultural, forest, and pasture lands, and maintaining the monuments in Lo-manthang for centuries. However, recent social-environmental dynamics such as climate change, migration, and modernization are reducing the relevancies of traditional norms and practices. Nevertheless, the institutions are working hard to continue their existence by frequently modifying their rules and norms.

Buffering new risks? Environmental, social and economic changes in the Turkana Basin during and after the African Humid Period

This paper evaluates risk-oriented frameworks for explaining environmental, social, and economic changes faced by fishing and herding communities in the Turkana Basin during and after the African Humid Period (AHP, 15–5 ka). The orbitally-forced AHP created moist conditions, high lake levels, and unusual hydrological connections across much of northern and eastern Africa. As arid conditions set in and rainfall decreased between 5.3 and 3.9 ka in eastern Africa, Lake Turkana (NW Kenya) shrank dramatically. Shoreline retreat coincided with an expansion of open plains, creating new ecological conditions and potential opportunities for early herders in the basin. In this changing landscape, economies shifted from food procurement (fishing/hunting aquatic resources) to food production (herding), likely through both in-migration by pastoralists and adoption of herding by local fishers. Early pastoralists also built at least seven megalithic pillar sites that served as communal cemeteries during this time. Recent research has shown that local environmental dynamics – both during and after the AHP – were complex, demanding a more careful interrogation of the notion that post-AHP life entailed new and/or heightened risks. Risk-buffering strategies might include mobility, diversification, physical storage, and exchange. Archaeologists working around Lake Turkana have proposed that economic shifts from fishing to pastoralism entailed increased mobility as a risk-buffering strategy to deal with aridity and resource unpredictability, and that pillar sites – as fixed landmarks in an unstable landscape – provided settings for congregation and exchange amongst increasingly mobile herding communities. However, recent research has shown that local environmental dynamics in the Lake Turkana basin – both during and after the AHP – were more complex than previously thought, necessitating re-evaluation of the notion that post-AHP life entailed new and/or heightened risks. Here, we explore risk buffering strategies (e.g. mobility, diversification, physical storage and/or exchange) as only one category of potential explanation for the new social practices observed in the region at this time. Gauging their applicability requires us to (a) assess the spatial mobility of communities and individuals interred at pillar sites; (b) evaluate whether and how mobility strategies may have changed as pastoralism supplanted fishing; and (c) examine alternative explanations for social and economic changes.

Gamma-ray spectrometry applied in the identification of potential acid mine drainage generation zones in waste rock pile with uranium ore and associated sulfides (caldas, Brazil)

Metal mining deeply modifies local environmental dynamics and produces large volumes of waste rock and residues, which is expected to be carefully disposed in order to prevent soil, water, and environment degradation. The Osamu Utsumi mine was a pioneer uranium ore exploitation site in Brazil, located in the State of Minas Gerais. The open pit and the high concentration of sulfide in waste rock piles are nowadays a dispendious concern to the Nuclear Industries of Brazil (INB, in Portuguese), due to sulfide oxidation and the resultant acid mine drainage (AMD). The objective of this research is to analyze the correlation between gamma-ray spectrometry data and the genera- tion of AMD in a waste rock pile, locally known as BF-04. Potassium concentrations can be used to distinguish zones of rock depletion, lowest concentrations, and radioelement sedimentation. The radiometric data acquisition combined with previous studies indicates that high uranium and tho- rium concentrations are associated with high sulfide zones. The mineralized uranium ore includes sulfides that are rapidly destroyed by surface hydration conditions, responsible for generating acid mine drainage. In this sense, superficial zones in the waste rock pile with high levels of eU and eTh are areas exposed to oxidation and hydration of sulfides, and, therefore, their recognition and neutralization can contribute to decrease AMD generation in the study site and areas with similar characteristics. The gamma-ray spectrometry results can subsidize more effective and low-cost reme- diation techniques.

Ecological specialization promotes diversity and diversification in the Eastern Mediterranean genus Ricotia (Brassicaceae)

AbstractDespite its amazing biodiversity, the Eastern Mediterranean remains a highly understudied region when compared with the Western Mediterranean, restricting our understanding of diversity across the entire Mediterranean. Here we use a combination of molecular markers and presence/absence data from all species of the Eastern Mediterranean genus Ricotia collected across its full geographic range to determine historical, ecological, and evolutionary factors responsible for lineage‐specific diversification in the Eastern Mediterranean. Network analysis based on molecular data revealed a high genetic structure within all lineages, and phylogenetic reconstructions based on the multispecies coalescent showed that within‐lineage diversification corresponded to the onset of the Mediterranean climate. Reconstruction of ancestral histories indicates that the genus originated within Anatolia and spread across the Eastern Mediterranean and Levant using the Taurus mountains. Ecological niche models suggest that local populations did not go through any major distributional shifts and have persisted in present‐day habitats since the Last Glacial Maximum. Furthermore, niche differentiation tests revealed significant differences between closely related species and showed the main variables predicting species limits to be different for each species. Our results give crucial information on the patterns and processes shaping diversity in the Eastern Mediterranean and show the main factors promoting diversification to be local environmental dynamics and ecological specialization and not large‐scale latitudinal movements, as often reported for southern Europe. By determining local and regional patterns of diversification in an Eastern Mediterranean genus, we further our understanding of the major trends influencing plant diversity in the Mediterranean basin as a whole.

Ocean Acidification Induces Changes in Virus-Host Relationships in Mediterranean Benthic Ecosystems.

Acidified marine systems represent “natural laboratories”, which provide opportunities to investigate the impacts of ocean acidification on different living components, including microbes. Here, we compared the benthic microbial response in four naturally acidified sites within the Southern Tyrrhenian Sea characterized by different acidification sources (i.e., CO2 emissions at Ischia, mixed gases at Panarea and Basiluzzo and acidified freshwater from karst rocks at Presidiana) and pH values. We investigated prokaryotic abundance, activity and biodiversity, viral abundance and prokaryotic infections, along with the biochemical composition of the sediment organic matter. We found that, despite differences in local environmental dynamics, viral life strategies change in acidified conditions from mainly lytic to temperate lifestyles (e.g., chronic infection), also resulting in a lowered impact on prokaryotic communities, which shift towards (chemo)autotrophic assemblages, with lower organic matter consumption. Taken together, these results suggest that ocean acidification exerts a deep control on microbial benthic assemblages, with important feedbacks on ecosystem functioning.

Global analysis of fish growth rates shows weaker responses to temperature than metabolic predictions

AbstractAimHigher temperatures increase the metabolic rate of ectothermic organisms up to a certain level and make them grow faster. This temperature‐sensitivity of growth is frequently used to predict the long‐term effects of climate warming on ectotherms. Yet, realized growth also depends on ecological factors and evolutionary adaptation. Here we study whether faster growth is observed along temperature clines within and between marine fish species from polar to tropical regions.LocationGlobal.Time periodThe sampling or publication year is for 718 observations before 1980, 1,073 observations between 1980 and 2000, and 390 observations after 2000 (for 336 observations no year was recorded).Major taxa studiedMarine teleost fish and elasmobranchs.MethodsThe effects of temperature on fish growth are studied using 2,517 growth observations, representing 771 species in 165 marine ecoregions. The effects of temperature are presented with a Q10, describing relative increase in the rate of growth for each 10 °C increase.ResultsWe find weak within‐ and between‐species effects of temperature on growth. The typical within‐species effect of temperature has a Q10 of 1.1. The between‐species effect is a little higher (Q10 = 1.4, or Q10 = 1.2 when corrected for phylogenetic relationships). When analysed per fish guild, growth responses vary from nearly independent of temperature in large demersals (Q10 = 1.1) to positive in small pelagics (Q10 = 1.6) and elasmobranchs (Q10 = 2.3). Average growth is higher in ecoregions with high primary production.Main conclusionThe change in average growth along temperature clines is weaker than predicted by metabolic theory, suggesting that the metabolic predictions are not sustainable in an ecosystem context. The long‐term response of fish to the increase in temperature associated with climate change may hence be shaped more by local environmental and ecological dynamics than by the physiological temperature response of the species currently present.

Limited evidence for common interannual trends in Baltic Sea summer phytoplankton biomass.

The Baltic Sea summer phytoplankton community plays an important role in biogeochemical cycling and in the transfer of energy through the food web via zooplankton. We aimed to improve the understanding of the degree to which large-scale versus local environmental dynamics regulate phytoplankton dynamics by analyzing time series at the Baltic Sea scale. We used dynamic factor analysis to study if there are common patterns of interannual variation that are shared (“common trends”) among summer phytoplankton total and class-level biomass time series observed across Baltic Sea latitudinal gradients in salinity and temperature. We evaluated alternative hypotheses regarding common trends among summer phytoplankton biomass: Baltic Sea-wide common trends; common trends by geography (latitude and basin); common trends differing among functional groups (phytoplankton classes); or common trends driven by both geography and functional group. Our results indicated little support for a common trend in total summer phytoplankton biomass. At a finer resolution, classes had common trends that were most closely associated with the cryptophyte and cyanobacteria time series with patterns that differed between northern and southern sampling stations. These common trends were also very sensitive to two anomalous years (1990, 2008) of cryptophyte biomass. The Baltic Sea Index, a regional climate index, was correlated with two common class trends that shifted in mean state around the mid-1990s. The limited coherence in phytoplankton biomass variation over time despite known, large-scale, ecosystem shifts suggests that stochastic dynamics at local scales limits the ability to observe common trends at the scale of monitoring data collection.

Linking Holocene vegetation dynamics, palaeoclimate variability and depositional patterns in coastal successions: Insights from the Po Delta plain of northern Italy

Mediterranean deltaic-coastal plains represent relatively underexplored depositional archives that record the Holocene response of vegetation and depositional systems to high-frequency climate changes. In this study, we examine a 25 m-thick succession of Holocene age (core EM2) recovered in the innermost portion of the Po delta plain of northern Italy, applying an integrated palyno-stratigraphic approach. The existence of a paludal, freshwater setting inland of the line of maximum marine transgression favoured a low degree of pollen transportation. Application of cluster analysis to this palynological record leads to the identification of pollen-derived biomes and seven (auto)ecological groups of taxa that discriminate environmental signal (depositional facies) and regional climate conditions within a well-dated coastal record. Percentage variations of hygrophytes, aquatics and pasture-meadow herbs reveal local environmental dynamics, enabling the detailed facies characterisation of the cored succession, especially in terms of water table conditions. Framed into a chronologically constrained, high-resolution facies context, the proportion of montane taxa (climate degradation indicator) relative to Mediterranean taxa and Quercus + other deciduous trees (climate optimum indicators) highlight a vegetation-climate variability in the plain that fits with Bond events, especially for the early-mid Holocene (i.e., Preboreal and Boreal Oscillation, 8.2 ka event), supporting a strong Mediterranean–North Atlantic climate connection. For the first time, pollen from a continental succession of the Adriatic area clearly depicts the effects of the 8.2 ka cooling event on vegetation patterns (progressive degradation in high altitude communities) and depositional dynamics (increased fluvial activity), assessing the major role played by climate changes in shaping coastal landscapes in addition to glacio-eustatic variations.

Putting responsive behaviours in place: Examining how formal and informal carers understand the actions of people with dementia

Living alongside and working with people with dementia who yell or strike out can be very demanding and sometimes harmful. It is generally understood that such actions may be a response to the social and physical environment, yet very little attention has been paid to understanding what role the environment plays in eliciting and responding to these actions across different settings. Drawing on 27 semi-structured interviews with formal and informal carers, this article examines how carers understand the actions of people with dementia in relation to their environment. We identify individual, interpersonal, local environmental, macro-scale and temporal dynamics that influence the actions of people with dementia and carers’ capacities to work with them. Drawing on relational thinking and the concept of structural violence, we argue that many of the problems and solutions associated with aggressive actions are located outside the person with dementia in broader relations and systems of care. We conclude with a discussion of how these understandings can inform developments in the systems of home and community care.

Perceptions of the Radiation Disaster from H-bomb Testing: Subsistence Economy, Knowledge and Network among the People of Rongelap in the Marshall Islands

This paper considers the various perceptions of victims of radiation and the suffering they experience from the radiation disaster. Many studies have been conducted on the adverse impacts of radiation. However, the discomfort and anxieties experienced by people were often ignored or dismissed as anecdotal evidence or emotionalism with no policy relevance. In this paper, findings are described from long-term work with the Rongelap community documenting the impact of radiation exposure from US nuclear testing as measured by changes in behavior and language. This paper shows that ecosystem changes from H-bomb radiation rendered traditional forms of knowledge about the natural environment meaningless; this is not to be confused with a loss of explicit knowledge, but it means that the knowledge is no longer applicable to the current situation. 'The people of Rongelap, Rongerik, and Ailinginae, like other Marshallese, had a keen understanding of local environmental conditions, resources, and ecosystemic dynamics. Ecosystem knowledge was essential to survival. Atoll resources provided water, food building materials, tools, transportation, medicine, toys, and ceremonial items.' In other words, nuclear testing resulted in the loss of some kinds of cultural knowledge. This is important to understand, because subsistence societies require more than uncontaminated natural resources to thrive. They also require knowledge of the natural environment. Simply transplanting a living culture to another location of similar size and geographic position does not work.

Ant pitfall trap sampling: An overview

Ants are widely distributed in both tropics and temperate regions at different altitudes. They are both scavengers and predators, and serve as indicators of climate change at micro and macro levels. Monitoring of ants in the context of local environmental dynamics is therefore very important. Among numerous sampling mechanisms for ants, the pitfall trap method is a reliable approach. Relevant information on the different aspects of pitfall trap usage has been presented in this review.

Determining virus-host interactions and glycerol metabolism profiles in geographically diverse solar salterns with metagenomics.

Solar salterns are excellent model ecosystems for studying virus-microbial interactions because of their low microbial diversity, environmental stability, and high viral density. By using the power of CRISPR spacers to link viruses to their prokaryotic hosts, we explored virus-host interactions in geographically diverse salterns. Using taxonomic profiling, we identified hosts such as archaeal Haloquadratum, Halorubrum, and Haloarcula and bacterial Salinibacter, and we found that community composition related to not only salinity but also local environmental dynamics. Characterizing glycerol metabolism genes in these metagenomes suggested Halorubrum and Haloquadratum possess most dihydroxyacetone kinase genes while Salinibacter possesses most glycerol-3-phosphate dehydrogenase genes. Using two different methods, we detected fewer CRISPR spacers in Haloquadratum-dominated compared with Halobacteriaceae-dominated saltern metagenomes. After CRISPR detection, spacers were aligned against haloviral genomes to map virus to host. While most alignments for each saltern metagenome linked viruses to Haloquadratum walsbyi, there were also alignments indicating interactions with the low abundance taxa Haloarcula and Haloferax. Further examination of the dinucleotide and trinucleotide usage differences between paired viruses and their hosts confirmed viruses and hosts had similar nucleotide usage signatures. Detection of cas genes in the salterns supported the possibility of CRISPR activity. Taken together, our studies suggest similar virus-host interactions exist in different solar salterns and that the glycerol metabolism gene dihydroxyacetone kinase is associated with Haloquadratum and Halorubrum.

A theoretical examination of environmental effects on the life cycle schedule and range limits of the invasive seaweed Undaria pinnatifida

Invasive macroalgae form a substantial component of marine invaders at a global level. However, it is poorly understood how the complex interactions between local environmental conditions and life cycle dynamics contribute to invasion success from a mechanistic viewpoint. The aim of this study was to use a model (UndariaGEN) that incorporates a detailed representation of the individual heteromorphic life history stages (sporophytes and gametophytes) of the species in order to explore how interactions between these components contribute to the overall population dynamics. The latest version of the model was validated against field data from a real-life population in Brittany, France. This was followed by an assessment of the role of temperature limitations in determining its potential global range and then a more detailed examination of how environmental factors affect the life cycle dynamics of U. pinnatifida across a range of conditions characteristic of European populations. In terms of both relative abundance and recruitment, the model matches closely the patterns observed from field studies in Brittany, France (R2 = 0.98 respectively). Furthermore, the model predicted theoretical temperature limits for growth (9.1–22.5 °C) match closely the actual current global range limits for the species (9.5–22.4 °C) reported in the literature. In addition, the size of the species’ ecological niche is shown to be directly related to the amplitude in seasonal variation of temperature. This demonstrates that U. pinnatifida has a wider ecological niche in conditions of high seasonality; this finding is consistent with theories that propose the heteromorphic life cycle may have evolved as an optimal growth strategy for highly seasonal environments.

Middle Miocene (Badenian) vegetation and climate dynamics in Bulgaria and Poland based on pollen data

The Miocene represents a time in Eurasia when evergreen and thermophilous dominated Paleogene vegetation was replaced by deciduous and temperate plants. Climatically, it is the transition from a greenhouse to an icehouse world, with the middle Miocene Climatic Optimum as the last warm episode of Earth history. Processes of plant evolution, transformation of vegetation and coenotic structure were significantly forced by both, changes in the global climate system, and also by significant palaeogeographic reorganizations. To give new insight in the middle Miocene evolution of European ecosystems and climate dynamics, we compared plant assemblages from northern Bulgaria and southern Poland (southern Paratethyan and Polish Lowlands realms).Based on palaeoecological analysis the main palaeocommunities are distinguished in hygro–hydrophytic herbaceous palaeocoenoses (reed marshes), hygrophytic forest palaeocoenoses (swamp forest and bush swamp), riparian forests, and mixed mesophytic forests. Despite some differences in taxonomic composition of these fossil floras and the proportion of individual taxa the vegetation shows similar composition and trends through time. The main trend in the vegetation dynamics is a general decrease in the abundance of palaeotropic and thermophilous elements of semi-evergreen forests. Together with these changes is a corresponding increase in the role of arctotertiary species in plant communities, and these plants became dominant in the mesophytic forests. Changes in swamp vegetation are climatically related too, but these reflect mainly local environmental dynamics and changes in inundation of the basin. Climate data from Bulgaria and Poland lack significant latitudinal climate gradient, thus confirming more or less homogenous climatic conditions within Europe in the middle Miocene.

Trophic structure of shallow-water benthic communities in the sub-Antarctic Strait of Magellan

Trophic structure is among the most fundamental characteristics of an ecosystem since it is a useful way to determine the main energy flow at the ecosystem level. In the Magellan Strait, the local spatial heterogeneity at the shallow-waters ecosystems may have a great variety of potential food sources; however, knowledge about their biological communities and their structure is still unclear. We examined the trophic structure of shallow-water-mixed bottom communities at two sites in the sub-Antarctic Magellan Strait based on carbon (δ 13C) and nitrogen (δ 15N) stable isotope ratios. The benthic communities were composed of 46 species from 20 major taxa at Bahia Laredo (BL) and 55 species from 18 major taxa at Punta Santa Ana (PSA). Benthic macroalgae and organic matter associated with sediment are the major primary food sources at both sites. Although both sites are quite similar in their food sources and in their vertical trophic structure (≥three trophic levels), the food web structure varied distinctly. Functionally, predators and grazers dominated both communities, but top predators were shorebirds, carnivore anemones and predatory nemerteans at BL, and sea stars, shorebirds, crabs and fishes at PSA. The distinct differences in the trophic structure at BL and PSA highlight the important variability of δ 15N at the base of the benthic food web, the role of local environmental conditions and community dynamics in structuring shallow-water communities.

Percepção ambiental e dinâmica geoecológica: premissas para o planejamento e gestão ambiental

É necessário planejar as ações do ser humano na natureza, organizar intervenções sustentáveis dentro dos limites ambientais, e gerir os recursos naturais através de comparações com outras paisagens já modificadas. Entretanto, grande parte das ações de planejamento e gestão ambiental se dão através de análises setoriais, sem entender como a população local percebe os seus lugares de vivência. Nesse artigo, discute-se sobre a análise geoecológica da paisagem e suas relações com o pensamento complexo, e sobre a importância da educação ambiental como forma de difusão do conhecimento geoecológico da paisagem. Propõe-se elementos entendidos como fundamentais para o planejamento e gestão ambiental dos recursos naturais e das paisagens, através de considerações acerca da necessidade de conhecimentos sobre a percepção ambiental dos atores sociais, de suas ações no ambiente natural, e das repercussões dessas ações na dinâmica geoecológica local. O uso da terra contribui significativamente para mudanças na dinâmica ambiental local, e assim, o entendimento sobre a dinâmica geoecológica e a percepção ambiental das comunidades locais devem ser encarados como premissas para elaboração das estratégias de planejamentos e gestão ambiental.

Long-term variability of the siphonophores Muggiaea atlantica and M. kochi in the Western English Channel

We investigated long-term variability of the calycophoran siphonophores Muggiaea atlantica and Muggiaea kochi in the Western English Channel (WEC) between 1930 and 2011. Our aims were to describe long-term changes in abundance and temporal distribution in relation to local environmental dynamics. In order to better understand mechanisms that regulate the species’ populations, we identified periods that were characteristic of in situ population growth and the environmental optima associated with these events. Our results show that between 1930 and the 1960s both M. atlantica and M. kochi were transient components of the WEC ecosystem. In the late 1960s M. atlantica, successfully established a resident population in the WEC, while the occurrence of M. kochi became increasingly sporadic. Once established as a resident species, the seasonal abundance and distribution of M. atlantica increased. Analysis of environmental conditions associated with in situ population growth revealed that temperature and prey were key determinants of the seasonal distribution and abundance of M. atlantica. Salinity was shown to have an indirect effect, likely representing a proxy for water circulation in the WEC. Anomalies in the seasonal cycle of salinity, indicating deviation from the usual circulation pattern in the WEC, were negatively associated with in situ growth, suggesting dispersal of the locally developing M. atlantica population. However, our findings identified complexity in the relationship between characteristics of the environment and M. atlantica variability. The transition from a period of transiency (1930–1968) to residency (1969–2011) was tentatively attributed to structural changes in the WEC ecosystem that occurred under the forcing of wider-scale hydroclimatic changes.