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Two new multi-proxy records of environmental change are provided from Horton Kirby Paper Mill and Old Seager Distillery in the Lower Thames Valley. Each site has evidence for a decline in elm woodland, which at Horton Kirby Paper Mill is recorded earlier than any other published record from the British Isles: sometime between 7320 and 7240 cal BP. Scolytus scolytus/S. multistriatus (the vectors for Dutch elm disease) are recorded after the decline in both sequences, adding to the number of sites with such evidence in the British Isles. Evidence of paludification and human activity are also recorded at the time of the elm decline reinforcing the multi-causal hypothesis. Integration of these results with 21 palaeoenvironmental records has produced a large number of well-dated, multiproxy records of the elm decline in this part of the UK. On the basis of this dataset, a classification system for categorising the relationships between the causal factors of the elm decline is proposed and recommended for future studies. [ABSTRACT FROM AUTHOR]

Mixed use has been extensively applied as an urban planning principle and hinders the study of single urban functions. To address this problem, it is worth decomposing the mixed use. Inspired by the concept of spectral unmixing in remote sensing applications, this paper proposes a framework for mixed-use decomposition based on big geo-data. Mixed-use decomposition in terms of human activities differs from traditional land use research, and it is more reasonable to infer the actual urban function of land. The framework consists of four steps, namely temporal activity signature extraction, urban function base curve extraction, mixed-use decomposition, and result validation. First, the temporal activity signatures (TASs) of each zone are extracted as the proxy of human activity patterns. Second, the diurnal TASs of routine activities are extracted as urban function base curves (i.e. endmembers). Third, a linear decomposition model is used to decompose the mixed use and obtain multiple results (urban function composition, dynamic activity proportions, and the mixing index). Finally, result validation strategies are concluded. This framework offers method extensibility and has few requirements for the input data. It is validated by means of a case study of Beijing, based on a social media check-in dataset. [ABSTRACT FROM AUTHOR]

This study analyzed the effects of climate variability and human activities on runoff and sediment yield of a watershed in the Central Rift Valley of Ethiopia since the 1980s. In the study, innovative trend analysis, the Pettitt test, and sequential regime shift detector methods were used to analyze trends and abrupt changes during the period 1981-2020. The Soil and Water Assessment Tool model was then integrated to disaggregate the contributions of climate variability, land-use change, and direct human activities on runoff and sediment yield at the watershed scale. The result indicates that the runoff and sediment yield decreased significantly with a sudden change in 2001. The study found that direct human activities played a dominant role, accounting for 57.9%, and 53.4% of annual runoff and sediment yield reduction, respectively. On the contrary, changes in climate and land use have led to a slight increase in runoff and sediment yield after 2001. The greater impacts of human activities can be attributed to the growth rate of water abstraction, and riverbed sand excavation during the past four decades. The findings of the result could be useful in supporting decision- makers in achieving watershed sustainability. [ABSTRACT FROM AUTHOR]

In recent decades, Digital transformation has significantly shifted human activities from physical space to cyber space. When users access the internet, uniform resource locator (URL) data are autogenerated. Using URLs, this study presents a novel framework for exploring cyber space structure from the perspectives of complex networks and activity fragmentation. Web domains within URL data are metaphorically regarded as 'digital locations,' and consecutive digital locations form 'cyber trajectories.' Human activities that occur at digital locations are semantically labeled and used to generate activity-based motifs. Motifs are defined as frequently occurring processes in cyber trajectories. Based on this, three network types are constructed: Global cyber human activity network, including all trajectories, and space-dependent and motif-dependent cyber human activity networks, focusing on specific regions and motifs. A case study conducted in Jilin, China, using approximately 4.3 gigabytes of URL data, revealed: 1) Cyber human activity patterns exhibit strong regularity and clustering of several types, with metropolitan regions favoring simpler patterns; 2) Cyber human activity networks demonstrate heavy-tailed and hierarchically polycentric structures; 3) The importance of websites in information dissemination increases super linearly along with their increased connectivity. This work deepens our understanding of cyber space functionality, offering insights into cyber information propagation. [ABSTRACT FROM AUTHOR]

This paper quantifies the impacts of climate variability and human activities on streamflow in the Chao River catchment near Beijing from 1986 to 1998. The year 1990 is found to be an inflection point for the impact of human activities. Streamflow is simulated for before and after 1990; monthly flow is simulated for the latter period. The contribution rate of climate to streamflow change in the catchment is found to be 17%; thus, the impact of human activities was far greater than that of climate variability over the entire period. [ABSTRACT FROM AUTHOR]

Today, the opportunity for potential human activity has gone beyond physical space to virtual space. Based on a proposed conceptual framework that models the relationships between physical and virtual spaces, this paper presents an attempt to adjust the space-time prism concept of Hägerstrand's time geography to identify potential activity opportunities in virtual space, focusing on the virtual space access channels available in physical space. A three-dimensional (3D) spatio-temporal Geographic Information System (GIS) design has been developed in this research to accommodate the adjusted space-time prism concept to support the representation, visualization, and analysis of potential human activities and interactions in physical and virtual spaces using the prism representation. Following the design, a prototype system has been successfully implemented in a 3D GIS environment. Such a system can provide powerful analytical tools for studies related to potential human activities and applications such as location-based services (LBS) and accessibility analysis in the information age. [ABSTRACT FROM AUTHOR]

When various urban functions are integrated into one location, they form a mixture of functions. The emerging big data promote an alternative way to identify mixed functions. However, current methods are largely unable to extract deep features in these data, resulting in low accuracy. In this study, we focused on recognizing mixed urban functions from the perspective of human activities, which are essential indicators of functional areas in a city. We proposed a framework to comprehensively extract deep features of human activities in big data, including activity dynamics, mobility interactions, and activity semantics, through representation learning methods. Then, integrating these features, we employed fuzzy clustering to identify the mixture of urban functions. We conducted a case study using taxi flow and social media data in Beijing, China, in which five urban functions and their correlations with land use were recognized. The mixture degree of urban functions in each location was revealed, which had a negative correlation with taxi trip distance. The results confirmed the advantages of our method in understanding mixed urban functions by employing various representation learning methods to comprehensively depict human activities. This study has important implications for urban planners in understanding urban systems and developing better strategies. [ABSTRACT FROM AUTHOR]

Ecological projects have huge impacts on vegetation restoration (VR) in China. However, are all of the effects due to human activities (HA) without the contribution of climate change (CC)? It is unclear what role CC plays in VR. Here, we quantitatively evaluate the contributions of climate change and human activities (CC_con and HA_con) to the net primary productivity (NPP) by the method of partial derivative and six different scenarios. HA contributed 61.19% to the NPP trend and controlled 32.84% of the NPP growth in China. Among the climate factors, temperature made the largest contribution to the NPP (45.89%) and had the largest control area (36.36%). CC promoted the positive HA_con in 54% of China, and in 68.35% of the area, the enhancement effect reached more than 50%. Our results answer a longstanding question and emphasize the important role of CC in enhancing the positive HA_con to VR. [ABSTRACT FROM AUTHOR]

Globally, community involvement in forest management has been hailed as an effective strategy to achieve both conservation and livelihoods improvement goals. In Uganda, Collaborative Forest Management (CFM) has been promoted to enable registered local community groups to co-manage specified areas of state forests with state agencies. However, there is paucity of empirical research evidence on conservation outcomes that are attributable to CFM. To fill this gap, this study used forest inventory data collected in compartments under different forest management regimes (CFM, inactive-CFM, and non-CFM) in 2003 and 2016 to assess spatial and temporal changes in forest structural attributes in a semideciduous forest in mid-western Uganda. Our ordination results show significant changes in tree communities in the non-CFM compartment. The CFM compartment registered a net increase in basal area. We attribute these changes to the high rate of illegal timber extraction and charcoal processing, with signs of the latter only recorded in the inactive- and non-CFM compartments. Illegal timber extraction was perpetuated by powerful outsiders while charcoal processing was dominated by local area residents for cash income. Deliberate management interventions should be instituted to curb illegal human activities and enhance regeneration and recruitment of target tree species in the forest. [ABSTRACT FROM AUTHOR]

A new probabilistic conceptual model, named the Assessment Model of Human Impact on Runoff Based on Stationarity Hypothesis (AMHIRBSH), was developed to attribute runoff variations to human activities through evaluating the changes in the runoff–runoff relationship (i.e. that between runoff of different watersheds). The AMHIRBSH was then applied to the Baiyangdian drainage basin, North China. After applying the Mann-Kendall test for trend and the Pettitt test for breakpoint, the runoff over the Baiyangdian drainage basin was shown to have had a breakpoint in approximately 1979, which split the time series into a baseline period (pre-1979) and an altered period (post-1979). The runoff was greatly reduced between these two periods. The runoff–runoff relationship of the Wangkuai and Xidayang sub-watersheds was evaluated using a copula function which showed it to have a non-stationarity degree of 35.64%, likely induced by massive afforestation programmes. This method provides an innovative perspective for attributing runoff variations to human activities. [ABSTRACT FROM AUTHOR]

Vegetation coverage directly affects the quality of a regional ecological environment. Current analyzes of the factors driving vegetation coverage do not focus on human activities. Poyang Lake is an internationally important wetland. This study is based on 814 MODIS normalized difference vegetation index (NDVI) data from 2000 to 2017 in the Poyang Lake Basin. Natural effects (temperature, precipitation, terrain niche index) and human activity intensity are employed to analyze the driving forces of NDVI changes. The results demonstrate the following: NDVI in the Poyang Lake Basin fluctuated and increased over the 18 years examined. Spatially, NDVI significantly decreased around the central city, and NDVI significantly increased on both sides of the river. NDVI changes are less affected by topographic factors and are more affected by climatic factors and human activities. Among the climatic factors, the correlation between NDVI and temperature was greater than that between NDVI and precipitation. Climatic factors had a greater impact on NDVI than human activities throughout the study area. However, in areas with significant NDVI changes, the correlation between climatic factors and NDVI was not obvious, and the correlation between human activities and NDVI was more obvious than in other areas. Therefore, from 2000 to 2017, the vegetation coverage of the Poyang Lake Basin generally showed an increasing trend; climatic factors had a greater impact on the overall vegetation coverage of the basin than human activities, but significant changes in vegetation coverage were caused by human activities. [ABSTRACT FROM AUTHOR]

The purpose of the article is to analyse the impact of COVID-19 on the agricultural supply chains and markets in Zimbabwe and subsequent effect on livelihoods. The research methodology that was applied is a systematic literature survey anchored on inductive research approach. This article is based on the systematic review of secondary data sources, such as journals, policy reports, as well as reports from national and international organizations. The review involved a predetermined and comprehensive approach of searching, analyzing and synthesizing extant literature on agricultural supply chains. In general, the pandemic has affected the whole supply chain from the food production systems and input supply, the storage and distribution, processing and packaging as well as the retail and marketing aspect. The research showed that the COVID-19 pandemic severely threatens an already critical food security situation arising mainly from the prevailing poor macroeconomic conditions and consecutive years of drought in Zimbabwe. This has led to a higher than previously anticipated food insecure population, especially in urban centers. Over 70% of the workers are self-employed and a vast majority operate in the informal sector. The informally employed represent a significant breadwinner constituency, whose dependents comprise vulnerable sections of the populace. The restrictions on mobility and the closure of borders meant immediate loss of employment and income. The study revisited the previous viruses such as Ebola to extrapolate though marginally, the implications of the COVID-19 pandemic. Using secondary sources and the general agriculture supply chain to guide understanding, the findings show that unless measures are put in place to safeguard farmers especially smallholder activities in Zimbabwe, COVID-19 has the potential to reproduce the same catastrophic implications created by Ebola in West Africa countries where peasant food systems where shattered and livelihoods strategies maimed. [ABSTRACT FROM AUTHOR]

A mechanistic understanding of human activity patterns lays a foundation for many applications. The majority of the current research aims to outline human activity patterns mainly from spatiotemporal perspectives (i.e., modeling human mobility patterns), lacking of understanding of the motivations behind behaviors. The aim of this study is to model and understand human activity patterns within urban areas using both spatiotemporal and cognitive psychology methods to measure both human behavior patterns and the underlying motivations. We first propose a framework that enables us to analyze the spatiotemporal patterns of urban human activities, infer the associated semantic patterns that represent the motivations driving human mobility choices and behaviors, and measure the similarity between human activities. We then construct a human activity network based on the similarity to depict human activity patterns. The framework is applied to a case study of Toronto, Canada, where geotagged tweets are used as a proxy for human activities to explore activity patterns. The analysis of the human activity network shows that 61% of tweeter users follow similar activity patterns. Our work provides a new tool for better understanding the way individuals interact with urban environments that could be applied\ to a variety of urban applications. [ABSTRACT FROM AUTHOR]

Water resources are the basis for the sustainable development of China. However, the country is currently facing alarming water-related problems associated with its fast economic development and climate change. This editorial introduces briefly the status of its water resources research at the national level and the researcher level. It also introduces the research reported in this thematic issue to highlight its role in addressing flood and water-scarcity issues, improving water management in inland plains and supporting the sustainable development of the country. Finally, some further recommendations for improving water resources research in China are offered. [ABSTRACT FROM AUTHOR]

Understanding urban functions and their relationships with human activities has great implications for smart and sustainable urban development. In this study, we present a novel approach to uncovering urban functions by aggregating human activities inferred from mobile phone positioning and social media data. First, the homes and workplaces (of travelers) are estimated from mobile phone positioning data to annotate the activities conducted at these locations. The remaining activities (such as shopping, schooling, transportation, recreation and entertainment) are labeled using a hidden Markov model with social knowledge learned from social media check-in data over a lengthy period. By aggregating identified human activities, hourly urban functions are inferred, and the diurnal dynamics of those functions are revealed. An empirical analysis was conducted for the case of Shenzhen, China. The results indicate that the proposed approach can capture citywide dynamics of both human activities and urban functions. It also suggests that although many urban areas have been officially labeled with a single land-use type, they may provide different functions over time depending on the types and range of human activities. The study demonstrates that combining different data on human activities could yield an improved understanding of urban functions, which would benefit short-term urban decision-making and long-term urban policy making. [ABSTRACT FROM PUBLISHER]

Gully erosion in the Black Soil Region of China has posed a threat to food security. This study aimed to determine the spatial distribution and morphologic characteristics of gullies in the region and their topographic thresholds. A 28 km² watershed was surveyed and 117 gullies measured. The results showed that: (1) Gullies were distributed equally on both hillslope and valley floor positions, with a total gully density of .66 km/km². (2)The mean depth, width, and cross-sectional area of gullies were .74 m, 2.39 m, and 2.43 m², respectively. These characteristics varied among gullies according to their topographic positions and slope gradients. Individual gully volume (V) was well predicted from gully length (L) by V= 2.08L0.96 (r² = .66). Total gully volume (V) of each sub-watershed was predicted from mean slope gradient (S) and drainage area (A) as V= 275800S - 8600A (r² = .73). (3) Gully erosion was more serious in steeper sub-watersheds and steeper hillslope positions. Gullies were wider in regions with relatively larger drainage areas, except for those developed in the main valley. The topographic threshold for gully initiation was S = .10A-0.34, which indicated gully erosion was dominated by surface runoff. (4) Human activities, such as road construction, played a significant role in gully erosion. [ABSTRACT FROM AUTHOR]

The Eastern Himalayan foothills constitute an important part of the Indo-Burma hotspot due to their richness in biodiversity and representative nature for the region. This contribution enhances the data bank on the variation in rich floral diversity from northeast India. Here, we present the first palynological report for the region on palaeovegetation and past climate variations as reflected in the Subankhata swamp of Assam. This is an attempt to show the affinity of the vegetation records of this swamp with Indo-Burma flora based on the remarkable similarity in the trend of vegetation changes over a time period of about 27,000 yrs. The studied palynoassemblage reflects six different vegetational and climatic phases (S-I to S-VI) since the Late Pleistocene. The first phase (S-I) comprises compact organic clay with a little silt. During this phase, a vast lowland savanna forest existed in a cool and dry climate regime similar to what was observed during the Ice Age. Later, during the S-II phase, the forest initially continued with little alteration in tree taxa under a relatively less cool and dry climate. Thereafter, the establishment of forest occurred under the influence of moderate monsoons that led to the onset of a warm and humid climate during the S-III phase which mainly comprises organic clay with silt. During the span of the S-IV phase, vegetation consisting of Dipterocarpaceae,Mesua ferrea,ElaeocarpusandSyzygiumare found, indicating warm and humid climatic conditions with high rainfall. The clearance of forest by humans has also been noted in this period. Subsequently, during the S-V zone, the beginning of a gradual decline in arboreals suggests an acceleration in forest clearance, possibly due to human activities as the climate turned warm and less humid. Entering the S-VI zone (probably Late Holocene), a drastic decline occurred in major tree elements, implying relatively dry climatic conditions indicating weakened monsoonal activity. The trend in our findings shows a clear affinity of these variations in the region with the whole Indo-Burma range since the Late Pleistocene. [ABSTRACT FROM AUTHOR]

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Human activity in the Lesser Antilles has led to the establishment of secondary herbaceous, shrubby and pre-forest communities. Today, vegetation cover is a mosaic of physionomic units of varying age, structure and floristic composition. These various components cover a range of specific biocenotic evolution levels. There are many degrees of complexity which correspond to the stages or phases of vegetative succession, the whole of which forms a dynamic gradient. In fact, over the course of time, the generalist species have supplanted those which, at the centre of pre-Columbian climax forest occupied highly specialised sites. The numeric data generated, with the help of macro-ecological and biogeographical methodologies as well as from naturalistic observations, has made possible the identification of the traits of vegetal dynamics. More specific future research, also relating to the dynamics of taxa, could use this general framework as a reference. [ABSTRACT FROM PUBLISHER]

This article addresses professional learning as intrinsic to social practices. It takes its point of departure in a sociocultural notion of mediation and communication in human activity and addresses the constitutive nature of language and artefacts as material-semiotic tools in the social coordination of perspectives and action, meaning-making and gap-bridging in professional work. The empirical examples are taken from different settings; an IT helpdesk team working in a multinational production company; vocational guidance officers working in a public employment office and from nurses at a rehabilitation ward in a hospital. The theoretical perspective is used when discussing these cases so as to display the use of the core concepts and the dynamics of change which may be illuminated by the analytical approach. In the conclusion, specific aspects of the materiality of social practice relevant for the study of learning and knowing in professional work are made salient. [ABSTRACT FROM AUTHOR]

This study evaluated the psychometric properties of the American English (Am. Eng.) version of the Occupational Value Assessment with predefined items (OVal-pd). The OVal-pd is a 26-item Likert-like questionnaire designed to assess the construct of occupational value as framed within the Value and Meaning in Occupations model (ValMO). Following a translation from the Swedish OVal-pd, 277 randomly selected graduate and undergraduate students from a public university in the northwestern United Stated completed the Am. Eng. OVal-pd. Test–retest and internal consistency reliability coefficients were very good utilizing an improved 22-item version of the OVal-pd. The structural validity of the 22-item Am. Eng. OVap-pd was partly confirmed through exploratory factor analysis. The scale was found to assess a one-dimensional value construct supporting the ValMO model, consisting of components clearly reflective of self-reward and concrete value. Exploratory factor analysis results were equivocal with regard to the symbolic dimension of the ValMO model as assessed by the OVal-pd. Discussion suggests the refinement of both the OVal-pd and ValMO model in the light of present and related empirical findings. [ABSTRACT FROM AUTHOR]

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Prevention and treatment of geological hazards is important for the sustainable development of human society. Surface geological hazards alone caused direct economic losses of ¥3.47 billion, with 768 deaths and 785 injuries in Guangdong Province, South China, from 1994 to 2005. The major factors causing geological hazards can be categorised into three types: geo-environmental, climatic-meteorological and human activity. Accompanied by rapid economic development and population growth, human activities can cause geological hazards that are as serious as those caused by natural factors. The authors propose some suggestions for prevention and treatment of geological hazards to achieve sustainable development on the Chinese coast. [ABSTRACT FROM AUTHOR]