In this work we aimed at developing a conceptual framework in which we improve our understanding of the controlling factors for soil organic carbon (SOC) over vast areas at different depths. We ...postulated that variability in SOC levels may be better explained by modeling SOC within soil‐landscape systems (SLSs). The study was performed in mainland France, and explanatory SOC models were developed for the sampled topsoil (0–30 cm) and subsoil (>30 cm), using both directed and undirected data‐mining techniques. With this study we demonstrated that there is a shift in controlling factors both in space and depth which were mainly related to (1) typical SLS characteristics and (2) human‐induced changes to SLSs. The controlling factors in relation to depth alter from predominantly biotic to more abiotic with increasing depth. Especially, water availability, soil texture, and physical protection control deeper stored SOC. In SLSs with similar SOC levels, different combinations of physical protection, the input of organic matter, and climatic conditions largely determined the SOC level. The SLS approach provided the means to partition the data into data sets that were having homogenous conditions with respect to this combination of controlling factors. This information may provide important information on the carbon storage and sequestration potential of a soil.
Key Points
SOC drivers alter from mainly biotic to abiotic with increasing soil depth
SOC storage depends on physical protection in addition to climate and OC input
Soil‐landscape systems explain large‐extent SOC dynamics in space and depth
Human-induced landscape change is difficult to predict due to the complexity inherent in both geomorphic and social systems as well as due to the coupling relationships between them. To better ...understand system complexity and system response to changing inputs, “connectivity thinking” has become an important recent paradigm within various disciplines including ecology, hydrology and geomorphology. With the presented conceptual connectivity framework on geomorphic change in human-impacted fluvial systems a cautionary note is flagged regarding the need (i) to include and to systematically conceptualise the role of different types of human agency in altering connectivity relationships in geomorphic systems and (ii) to integrate notions of human-environment interactions to connectivity concepts in geomorphology to better explain causes and trajectories of landscape change. Geomorphic response of fluvial systems to human disturbance is shown to be determined by system-specific boundary conditions (incl. system history, related legacy effects and lag times), vegetation dynamics and human-induced functional relationships (i.e. feedback mechanisms) between the different spatial dimensions of connectivity. It is further demonstrated how changes in social systems can trigger a process-response feedback loop between social and geomorphic systems that further governs the trajectory of landscape change in coupled human-geomorphic systems.
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•SOC storage potential in cropland topsoil was estimated by a data-driven approach.•Carbon landscape systems were determined by mixture model clustering analysis.•Drivers of SOC ...storage potential varies in carbon landscape systems.•Cropping and soil managements explained ∼20 % of SOC storage potential variability.•Conversion to rice-based cropping systems can partly achieve 4p1000 initiative.
Soil organic carbon (SOC) is receiving increasing attention due to its large storage potential in global carbon cycles and its great importance to soil fertility, agricultural production, and ecosystem services. The increases of SOC storage and reliable estimation of its potential are essential for evaluating the soil sustainability and climate change adaptation under intensive cultivation. In this work, a data-driven approach combining mixture clustering and Random Forest models was proposed to estimate the SOC storage potential of cropland topsoil and its controlling factors in East China. The carbon landscapes systems (CLSs) were delineated using a mixture clustering model by combining the climatic condition, soil properties, cropping systems, and soil management practices. The SOC storage potentials with 95 % confidence intervals at 250 m spatial resolution were estimated as the difference between the current SOC stock and empirically maximum SOC stock at basic (75 %), intermediate (85 %), and ambitious (95 %) expectation objectives for each CLS. The SOC storage potential increased with the increasing of expectation objective settings, with the averaged levels of 13.1, 20.8, and 35.5 t C ha−1 at 75 %, 85 %, and 95 % percentile objectives, respectively. The variable importance from Random Forest indicated that the cropping systems and soil management practices were the unignorable factors controlling the SOC storage potential beyond the climatic conditions and soil properties. Moreover, the shifts of human-induced controlling factors, e.g., cropping systems, also indicated their capability of SOC sequestration potential for partly achieving the “4p1000” initiative (annual growth rate of 0.4 % carbon stocks in the first 30 cm of topsoil). The currently optimal soil management practices for achieving the SOC sequestration potential was the combination of rice-based cropping systems, straw return, and organic fertilizer applied. The data-driven approach coupling with CLSs improved our understanding of the controlling factors on SOC storage potential at regional level with homogenous conditions, enabling evidence-based decision making in promoting carbon sequestration by adopting locally feasible soil management practices.
A zona costeira de Maputo representa um dos últimos redutos de terra livre na capital moçambicana, ao mesmo tempo que se torna o bastião de uma nova imagem de cidade, inscrita no ideário neoliberal ...dominante. Na prática, entre propostas e projectos de intervenção diversos, orientados sobretudo para a lógica de mercado, os bairros autoproduzidos vão tecendo um tecido urbano pr óprio, fruto da sobreposição a sistemas da paisagem, nomeadamente dunas e áreas de mangal. Partindo do pressuposto da existência de uma só paisagem, a humanizada e as suas dinâ micas, propõe-se a leitura da zona costeira de Maputo enquanto sistema, tendo em conta os múltiplos factores naturais e sociais que a marcam e as mudanças das suas dinâmicas ao longo das ú ltimas décadas. Com base num trabalho de campo aprofundado, realizado no quadro de uma investigação de doutoramento em curso, caracteriza-se o tecido urbano autoproduzido em áreas ecologicamente vulneráveis, de forma a identificar e melhor compreender as dinâmicas da paisagem, à luz da (auto)produção do espaço. Tomando como caso-estudo o Bairro dos Pescadores, na Costa do Sol, analisa-se a transformação do tecido (auto)produzido e a sua relação com a paisagem a partir do início do novo milénio, acompanhando a consolidação do actual contexto neoliberal. Ao cartografar as interacções estabelecidas entre a expansão e densificação do tecido urbano e a paisagem onde se insere reflectimos sobre a influência dos seus elementos na forma urbana e o significado que adquirem para os moradores.
Ever since its beginnings, landscape ecology has been developing in two different directions: the bioecological and the geoecological. While the bioecological approach is focused on the relationship ...between organisms and their abiotic environment, the geoecological approach is based on the relationship between human society and its, primarily abiotic, environment. Therefore, the geoecological approach can be applied in planning human use of the environment in a long term sustainable manner, while the bioecological approach could represent the basis for the planning of conservational and environmental usage. The merging of these two approaches will result in a comprehensive and more holistic landscape ecology, which will thus gain the potential for coordinating interdisciplinary landscape research and a more prominent role in contributing to spatial planning. The merge will also enhance attempts to create a general theory of landscape systems.
•MaxEnt modelling identified distribution factors of Korea’s village groves.•The probability of grove occurrence had a unimodal relation with population density.•The probability of grove occurrence ...was low when forest cover was high (>80%).•Climatic factors also affected the probability of grove occurrence.•Conservation efforts should address human effects on community-based landscape.
Our study aims to understand the spatial context of community-based landscape systems for conservation planning. To this end, the present study analyzes the factors affecting spatial distribution of Korea’s traditional village groves, which form a distinctive component of Korea’s traditional community-based landscape. Using maximum entropy (MaxEnt) modeling, we identified four strongest contributory factors that affect the current occurrences of village groves. First, the probability of occurrences declined with increasing human population density within a 300 m radius, and, second, it was lower where there was high forest cover (>80%) within a 500 m radius. Third, we found a unimodal pattern for the occurrence probability for precipitation during the coldest quarter with the probability peaking in areas where mean precipitation is 118 mm, while the occurrence probability for mean diurnal temperature range was generally positively correlated. Based on the assumption that spatial analysis could highlight priorities and implications for conservation, our results reveal the importance of understanding the grove landscape as a manifestation of the linkages between nature and humans as well as the importance of modern scientific approaches to manage the spatial elements of traditional landscape systems.
Variations in geo-environmental attributes differ strongly from those of urban anthropogenic structures. Similarly, these types of structures are self-directed and arranged and prone to abrupt ...process-related changes and modifications. Thus, there are many reasons why planned urbanization forms in association with disturbances in ecosystem mobility. The current research highlights these variations in the context of social-cultural assessments within the Jhelum River watershed, which strongly expresses urbanization structure development mechanisms. The climate ranges from semi-arid to subhumid subtropical and sub-mountainous climate, though the extreme temperatures may rise as high as 49.4°C in June and may drop as low as −1.6°C in January. The rainfall is low in the southwest and gradually increases towards the northeast, whereas the Salt Range is the major topographic feature that controls climatic impacts and promotes sustainable development. Cross-disciplinary methods are adopted in this investigation to assess the social-ecological landscape system (SELS) in terms of its mobility and degree of urbanization. The Sustainable Development Goals of the 2030 Agenda recognize that human livelihoods and the management of natural resources cannot be addressed separately. Investing in the sustainability of mountain communities and ecosystem conservation and protection will provide benefits for humanity as a whole. It pertains to the commensurate development of the SELS and its response to interruptions. Thus, a reliable SWOT analysis for management approaches is introduced that may enable the development of competencies that promote and lead towards rapid improvements in the sustainability of retrograde urban infrastructure, including watersheds.
Feedbacks in Human–Landscape Systems Chin, Anne; Florsheim, Joan L; Wohl, Ellen ...
Environmental management (New York),
2014, 1-2014, 2014-Jan, 2014-1-00, 20140101, Volume:
53, Issue:
1
Journal Article
Peer reviewed
This article identifies key questions and challenges for geomorphologists in investigating coupled feedbacks in human–landscape systems. While feedbacks occur in the absence of human influences, they ...are also altered by human activity. Feedbacks are a key element to understanding human-influenced geomorphic systems in ways that extend our traditional approach of considering humans as unidirectional drivers of change. Feedbacks have been increasingly identified in Earth-environmental systems, with studies of coupled human–natural systems emphasizing ecological phenomena in producing emerging concepts for social–ecological systems. Enormous gaps or uncertainties in knowledge remain with respect to understanding impact-feedback loops within geomorphic systems with significant human alterations, where the impacted geomorphic systems in turn affect humans. Geomorphology should play an important role in public policy by identifying the many diffuse and subtle feedbacks of both local- and global-scale processes. This role is urgent, while time may still be available to mitigate the impacts that limit the sustainability of human societies. Challenges for geomorphology include identification of the often weak feedbacks that occur over varied time and space scales ranging from geologic time to single isolated events and very short time periods, the lack of available data linking impact with response, the identification of multiple thresholds that trigger feedback mechanisms, the varied tools and metrics needed to represent both physical and human processes, and the need to collaborate with social scientists with expertise in the human causes of geomorphic change, as well as the human responses to such change.