A qualitative approach to evaluating the impact of human interventions on the middle Charente River (West France)

Author(s):  
Amélie Duquesne ◽  
Christine Plumejeaud-Perreau ◽  
Jean-Michel Carozza

<p><span>Although many studies have analyzed the impact of human interventions on European rivers over decades or centuries, researchers have rarely evaluated the geomorphological effects of these anthropogenic pressures on fluvial systems. However, quantifying anthropogenic impacts is fundamental to understanding how rivers are affected by human interventions and to improving the river management and restoration. The aim of this study is to propose a new and original qualitative method to estimate the importance of human impacts on rivers over the last three centuries using the middle Charente River as a test case. The study area is an anastomosing, low-energy and little mobile river of the lowlands of Western France. It extends from the city of Angoulême (Charente) to the city of Saintes (Charente-Maritime), with a length of approximately 100 km. The study segment has been subjected to high anthropogenic pressure since the High Middle Ages, and it was enhanced during the 19th century to facilitate navigation and terrestrial transportation, to ensure the exploitation of the water's driving force (water mills and paper mills), to maintain the local people (fishing dams and agro-pastoral uses) and to allow for flood protection. To understand and estimate the anthropogenic heritage of the Charente River, this study employed a two-stage method: 1) an inventory of the human interventions on the fluvial system through the consultation of geo-historical data (textual archives, historical maps and iconography) dating from the end of the 17th century to the 2010s and 2) an evaluation of the human impact of each human intervention, sub-category and category of intervention based on the calculation of the Cumulative Human Impact Index. The Cumulative Human Impact Index is composed of several qualitative attributes graded by an evaluator. The results allow one 1) to generate a database and typology of the human interventions affecting the middle Charente River over the long term; 2) to map the cumulative impacts of human interventions on the study area; and 3) to analyze the unitary and overall impact of each human intervention, sub-category and category of intervention on the river landscape's heritage. Finally, this study concludes with 1) a discussion of the advantages of using a qualitative methodology for the estimation of anthropogenic impacts and 2) a reflection on the use of the maps of cumulative human impacts for Charente River management and restoration.</span></p>

2008 ◽  
Vol 72 (1) ◽  
pp. 411-413 ◽  
Author(s):  
T. Eskola ◽  
V. Peuraniemi

AbstractLake sediments were studied from four lakes in environmentally different areas in northern Finland. Lakes Pyykösjärvi and Kuivasjärvi are situated near roads with heavy traffic and the city of Oulu. Lakes Martinlampi and Umpilampi are small lakes in a forest area with no immediate human impact nearby. The concentration of Pb increases in the upper parts of the sedimentary columns of Lake Kuivasjärvi and Lake Pyykösjärvi. This is interpreted as being an anthropogenic effect related to heavy traffic in the area and use of Lake Pyykösjärvi as an airport during World War II. High Ni and Zn concentrations in the Lake Umpilampi sediments are caused by weathered black schists. Sediments in Lake Martinlampi show high Pb and Zn contents with increasing Pb concentrations up through the sedimentary column. The sources of these elements are probably Pb-Zn mineralization in the bedrock, Pb-Zn-rich boulders and anomalous Pb and Zn contents in till in the catchment area of the lake.


Oryx ◽  
2015 ◽  
Vol 51 (1) ◽  
pp. 60-67 ◽  
Author(s):  
Bakri Nadhurou ◽  
Roberta Righini ◽  
Marco Gamba ◽  
Paola Laiolo ◽  
Ahmed Ouledi ◽  
...  

AbstractThe decline of the mongoose lemur Eulemur mongoz has resulted in a change of its conservation status from Vulnerable to Critically Endangered. Assessing the current threats to the species and the attitudes of the people coexisting with it is fundamental to understanding whether and how human impacts may affect populations. A questionnaire-based analysis was used to study the impact of agriculture and other subsistence activities, and local educational initiatives, on lemur abundance, group size and composition in the Comoros. On the islands of Mohéli and Anjouan we recorded 214 lemurs in 63 groups, the size and composition of which depended both on environmental parameters and the magnitude and type of anthropogenic pressure. There was no evidence of an impact of anthropogenic disturbance on abundance. In contrast, group size and composition were sensitive to human impacts. The most important threats were conflicts related to crop raiding, as well as illegal capture and hunting. The promotion of educational activities reduced the negative impact of hunting and illegal activities. These results highlight a need for urgent conservation measures to protect the species.


2017 ◽  
Vol 21 (11) ◽  
pp. 5603-5626 ◽  
Author(s):  
Joyce H. C. Bosmans ◽  
Ludovicus P. H. van Beek ◽  
Edwin H. Sutanudjaja ◽  
Marc F. P. Bierkens

Abstract. Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or include the impact of land cover change. Here we use PCR-GLOBWB, a combined global hydrological and water resources model, to assess the impacts of land cover change as well as human water use globally in different climatic zones. Our results show that land cover change has a strong effect on the global hydrological cycle, on the same order of magnitude as the effect of human water use (applying irrigation, abstracting water, for industrial use for example, including reservoirs, etc.). When globally averaged, changing the land cover from that of 1850 to that of 2000 increases discharge through reduced evapotranspiration. The effect of land cover change shows large spatial variability in magnitude and sign of change depending on, for example, the specific land cover change and climate zone. Overall, land cover effects on evapotranspiration are largest for the transition of tall natural vegetation to crops in energy-limited equatorial and warm temperate regions. In contrast, the inclusion of irrigation, water abstraction and reservoirs reduces global discharge through enhanced evaporation over irrigated areas and reservoirs as well as through water consumption. Hence, in some areas land cover change and water distribution both reduce discharge, while in other areas the effects may partly cancel out. The relative importance of both types of impacts varies spatially across climatic zones. From this study we conclude that land cover change needs to be considered when studying anthropogenic impacts on water resources.


Diversity ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 374
Author(s):  
Monika Eliasz-Kowalska ◽  
Agata Z. Wojtal

Determination of the relationships between environmental factors and diatom assemblages is usually made for several hundred lakes spread over a large area. However, the analysis of several lakes located near Lake Wigry also gives interesting results. Lakes in Wigry National Park (Poland) with broad similarity of geological origin show clear limnological, physical, and chemical differences. Here, we report on an investigation into how these dissimilarities influence diatom assemblages. Hierarchical Cluster Analysis showed that the studied lakes can be divided into three groups: (1) disharmonic, (2) harmonious with greater human impact on the environment, and (3) harmonious with a more limited human impact. The harmonious lakes could be divided into two groups that are mainly in line with the contents of the chloride and sulfates ions taken as indicative of human impacts on the environment. Overall, the three groups had different dominance structures, as reference to the Dominance Index (DI) made clear (mean values being: (1) −70.54%, (2) −72%, and (3) −54.58%, Generalized Linear Models with the categorical independent variable (group) showed significant differences between groups (for 1–3, 2–3) p value < 0.05). Lakes impacted by anthropopressure and disharmonic ones had the strongest dominance structure. More broadly, DI differences between the groups are consistent with the Species Pool Hypothesis (SPH), while studied differences can be said to result from natural geological dissimilarities, as well as disparate anthropogenic impacts.


2018 ◽  
Author(s):  
Grace E.P. Murphy ◽  
Melisa Wong ◽  
Heike K. Lotze

AbstractCoastal biogenic habitats are particularly vulnerable to cumulative human impacts from both terrestrial and marine realms. Yet the broad spatial scale used in current global or regional approaches of quantifying multiple anthropogenic stressors are not relevant to the local or bay-wide scales affecting most coastal biogenic habitats. To fill this gap, we developed a standardized human impact metric to quantify the magnitude of anthropogenic impacts to coastal ecosystems more broadly, and biogenic habitats in particular. We applied this metric to 180 seagrass beds (Zostera marina), an important biogenic habitat prioritized for marine protection, across Atlantic Canada. Our impact metric includes five bay-scale and four local-scale terrestrial and marine-based impacts. Results show that seagrass beds and coastal bays in Atlantic Canada exist across a wide gradient of human impacts. Considerable differences in the range and intensity of impacts within and between regions provide insight into where coastal bays and seagrass ecosystems are expected to be most and least affected by individual or cumulative human threats. We discuss implications for management and conservation planning, and the general application of our impact metric to other coastal regions and habitats in Canada and beyond.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1440
Author(s):  
Beata Fornal-Pieniak ◽  
Barbara Żarska ◽  
Marcin Ollik

The purpose of the research was the recognition of edge effects regarding similarities and differences of vascular flora in undergrowth layers in the urban forest ecotones. Four types of urban forest neighborhoods were analyzed: ecotones adjacent to the manor park, the agriculture field, housing estates and the road. The plant compositions in the forest ecotones were compared with the plant compositions in the urban forest interior and the forest nature reserve. The phytosociological type of studied forests was a subcontinental oak-hornbeam one (Tilio-Carpinetum). Diagnostic plant species (e.g., characteristic) for forests from the non-diagnostic ones were identified. Forest consistent plant species dominated in the ecotone adjacent to the manor park and in the interior of urban forests too, but the best conditions for these plants were inside the forest nature reserve, where native consistent forest plants showed the highest dominance when comparing all studied areas. A higher anthropogenic pressure from the adjacent areas results in supporting the growth of inconsistent plant species in the forests, and these plants are mostly represented by plants belonging to grass and synanthropic communities. Another conclusion drawn from our research is that the protected forest, represented by a nature reserve in the city, provides better “shelter” for native forest plants than the urban forest without any protection. Ultimately, a permanent challenge is to achieve and maintain the balance between nature and the impact of anthropogenic activities on urban forests in the city. The high quality of green areas, biodiversity, including forests, implicates possibilities of sustainable development in cities. The research results will be useful for local urban planners and ecologists during their work on strategies of city development, including shaping of green infrastructure.


FACETS ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 210-237 ◽  
Author(s):  
Grace E.P. Murphy ◽  
Melisa C. Wong ◽  
Heike K. Lotze

Coastal biogenic habitats are vulnerable to human impacts from both terrestrial and marine realms. Yet the broad spatial scale used in current approaches of quantifying anthropogenic stressors is not relevant to the finer scales affecting most coastal habitats. We developed a standardized human impact metric that includes five bay-scale and four local-scale (0–1 km) terrestrial and marine-based impacts to quantify the magnitude of anthropogenic impacts to coastal bays and nearshore biogenic habitats. We applied this metric to 180 seagrass beds ( Zostera marina), an important biogenic habitat prioritized for marine protection, in 52 bays across Atlantic Canada. The results show that seagrass beds and coastal bays exist across a wide human impact gradient and provide insight into which are the most and least affected by human threats. Generally, land alteration, nutrient loading, and shellfish aquaculture were higher in the Gulf of St. Lawrence, whereas invasive species and fishing activities were higher along the Atlantic coast. Sixty-four percent of bays were at risk of seagrass decline from nitrogen loading. We also found high within-bay variation in impact intensity, emphasizing the necessity of quantifying impacts at multiple spatial scales. We discuss implications for management and conservation planning, and application to other coastal habitats in Canada and beyond.


Author(s):  
Mikhail Slepnev ◽  
Evgeniya Filyakova

The article considers the impact of recreational load on the natural-anthropogenic region — Central park «Kul'tury I Otdykha» in the city of Oryol. To ensure the sustainable development of natural areas, the ability of components of the environment to heal itself in the conditions of anthropogenic impact is of particu-lar importance. Most of the anthropogenic load in a large city is the recreational load, which significantly affects the natural frame of urban areas. Recreational load causes a significant degradation of the natural complex of the city, and its value is determined by the planning structure of urban development, which deter-mines the distribution of population density and transport accessibility of recreation facilities. Calculated data revealed the recreational load from the planning structure of the residential area located within walking distance from the coastal recreational zone. Ensuring the safety of urban parks, it is necessary to work with complete and reliable information that can only be obtained through regular monitoring studies. The spatial organization of coastal recreational zones should meet the objectives of maintaining and improving the eco-logical balance of recreational areas, as well as the formation of a comfortable architectural and planning structure of recreational zones and the selection of the most significant recreational formations based on the ecological and recreational capabilities of natural areas and the needs of the population. In this regard, it is necessary to develop functional zoning of natural-anthropogenic regions to regulate the level of recreational impact, and ensure the sustainability of ecological systems of the city. To monitor the level of anthropogenic impacts, the definition is used — the ecological capacity, which is determined by the limiting values of an-thropogenic loads determined on the basis of field observations.


2019 ◽  
Vol 80 (3) ◽  
pp. 408-417
Author(s):  
Xiaoyu Liang ◽  
Mi-Hyun Park ◽  
Michael K. Stenstrom

Abstract Trash is one of major pollutants in urban runoff. Some studies have been conducted to verify the different impacts of land use on trash generation in a qualitative way and focused on the performance of trash control measures. Few studies have explored the human impacts on trash generation or developed a quantitative model to describe the phenomenon. This paper examined the impact of human activity on trash generation. Spatial regimes on high trash generation areas were identified using the selected variables from best subset model regression and validated with Moran's I scatter plot and spatial analysis of variance. Bidirectional spatial lag regression with regimes was performed to develop the final model to explain the spatial distribution of trash generation and identify its major causes. The result showed that economic status and occupation of the population were correlated with trash accumulation and the dominant land use type, and the distance to rivers most affected trash generation. The effects of these indicators were different within and outside the high trash generation areas.


2016 ◽  
Author(s):  
Joyce H. C. Bosmans ◽  
L. P. H. (Rens) van Beek ◽  
Edwin H. Sutanudjaja ◽  
Marc F. P. Bierkens

Abstract. Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or include the impact of land cover change. Here we use the global hydrological and water resources model PCR-GLOBWB to assess the impacts of land cover change as well as human water use. Our results show that land cover change has a strong effect on the global hydrological cycle, at least as strong as the effect of human water use (applying irrigation, abstracting water for e.g. industrial use, including reservoirs etc). Globally averaged, changing the land cover from 1850 to that of 2000 increases discharge through reduced evapotranspiration, with large spatial variability in magnitude and sign of change depending on e.g. the specific land cover change and climate zone. In contrast, the inclusion of irrigation, water abstraction and reservoirs reduces global discharge through enhanced evaporation over irrigated areas and reservoirs as well as water consumption. Hence in some areas land cover change and water distribution both reduce discharge, while in other areas the effects may partly cancel out. The relative importance of both types of impacts varies spatially. From this study we conclude that land cover change needs to be considered when studying anthropogenic impacts on water resources.


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