scholarly journals A human impact metric for coastal ecosystems with application to seagrass beds in Atlantic Canada

2018 ◽  
Author(s):  
Grace E.P. Murphy ◽  
Melisa Wong ◽  
Heike K. Lotze
Keyword(s):  
Human Impact ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Coastal Ecosystems ◽  
Atlantic Canada ◽  
Seagrass Beds ◽  
General Application ◽  
Coastal Bays ◽  
Biogenic Habitat ◽  
Seagrass Ecosystems

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.

scholarly journals A human impact metric for coastal ecosystems with application to seagrass beds in Atlantic Canada

FACETS ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 210-237 ◽  
Author(s):  
Grace E.P. Murphy ◽  
Melisa C. Wong ◽  
Heike K. Lotze
Keyword(s):  
Human Impact ◽  
Nutrient Loading ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Spatial Scales ◽  
Nitrogen Loading ◽  
Atlantic Canada ◽  
Seagrass Beds ◽  
Coastal Habitats ◽  
Coastal Bays

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.

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

2020 ◽  
Author(s):  
Amélie Duquesne ◽  
Christine Plumejeaud-Perreau ◽  
Jean-Michel Carozza
Keyword(s):  
Human Impact ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
River Management ◽  
Anthropogenic Pressure ◽  
Human Intervention ◽  
Impact Index ◽  
Human Interventions ◽  
The Impact ◽  
The City

<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>

scholarly journals Production of mobile invertebrate communities on shallow reefs from temperate to tropical seas

2020 ◽  
Vol 287 (1941) ◽  
pp. 20201798
Author(s):  
K. M. Fraser ◽  
J. S. Lefcheck ◽  
S. D. Ling ◽  
C. Mellin ◽  
R. D. Stuart-Smith ◽  
...  
Keyword(s):  
Primary Productivity ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Selection Procedure ◽  
Marine Ecosystems ◽  
Environmental Drivers ◽  
Kelp Forests ◽  
Food Web Structure ◽  
Continental Scale ◽  
Biogenic Habitat

Primary productivity of marine ecosystems is largely driven by broad gradients in environmental and ecological properties. By contrast, secondary productivity tends to be more variable, influenced by bottom-up (resource-driven) and top-down (predatory) processes, other environmental drivers, and mediation by the physical structure of habitats. Here, we use a continental-scale dataset on small mobile invertebrates (epifauna), common on surfaces in all marine ecosystems, to test influences of potential drivers of temperature-standardized secondary production across a large biogeographic range. We found epifaunal production to be remarkably consistent along a temperate to tropical Australian latitudinal gradient of 28.6°, spanning kelp forests to coral reefs (approx. 3500 km). Using a model selection procedure, epifaunal production was primarily related to biogenic habitat group, which explained up to 45% of total variability. Production was otherwise invariant to predictors capturing primary productivity, the local biomass of fishes (proxy for predation pressure), and environmental, geographical, and human impacts. Highly predictable levels of epifaunal productivity associated with distinct habitat groups across continental scales should allow accurate modelling of the contributions of these ubiquitous invertebrates to coastal food webs, thus improving understanding of likely changes to food web structure with ocean warming and other anthropogenic impacts on marine ecosystems.

scholarly journals Limnological Characteristics and Diatom Dominants in Lakes of Northeastern Poland

Diversity ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 374
Author(s):  
Monika Eliasz-Kowalska ◽  
Agata Z. Wojtal
Keyword(s):  
Human Impact ◽  
Linear Models ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Hierarchical Cluster ◽  
P Value ◽  
Diatom Assemblages ◽  
Large Area ◽  
Mean Values ◽  
Dominance Structure

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.

Natural and anthropogenic impacts on the composition of lake sediments

2008 ◽  
Vol 72 (1) ◽  
pp. 411-413 ◽  
Author(s):  
T. Eskola ◽  
V. Peuraniemi
Keyword(s):  
World War Ii ◽  
Lake Sediments ◽  
Human Impact ◽  
Catchment Area ◽  
Anthropogenic Impacts ◽  
Heavy Traffic ◽  
World War ◽  
Small Lakes ◽  
Anthropogenic Effect ◽  
The City

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.

Seagrass Ecosystems of Andaman and Nicobar Islands: Status and Future Perspective

2020 ◽  
Vol 7 (4) ◽  
pp. 169-174
Author(s):  
Chatragadda Ramesh ◽  
Raju Mohanraju
Keyword(s):  
Water Quality ◽  
Primary Production ◽  
Environmental Changes ◽  
Future Perspective ◽  
Marine Biodiversity ◽  
Seagrass Beds ◽  
Seagrass Meadows ◽  
Seagrass Ecosystem ◽  
Seagrass Ecosystems ◽  
Nicobar Islands

Seagrasses are unique marine flowering plants that play an important ecological role by yielding primary production and carbon sequestration to the marine environment. Seagrass ecosystems are rich in organic matter, supporting the growth of bio-medically important epi and endophytic microorganisms and harbor rich marine biodiversity. They are an essential food source for endangered Andaman state animal Dugongs. Seagrasses are very sensitive to water quality changes, and therefore they serve as ecological bio-indicators for environmental changes. The benthic components in and around the seagrass beds support a significant food chain for other Micro and organisms apart from fishery resources. The epiphytic bacterial communities of the leaf blades support the sustenance against the diseases. Recent reports have shown that the loss of seagrass beds in tropical and temperate regions emphasizes the depletion of these resources, and proper management of seagrass is urgent. The decline of seagrass will impact primary production, biodiversity, and adjacent ecosystems, such as reefs. Therefore, restoring the seagrass meadows could be possible with effective implementing management programs, including seagrass meadows in marine protected areas, restoration projects, seagrass transplantation, implementation of legislative rules, monitoring coastal water quality and human activities in the coastal zone. Lacunas on the seagrass ecosystem management in Andaman & Nicobar Islands are addressed.

scholarly journals Identifying Human-Induced Spatial Differences of Soil Erosion Change in a Hilly Red Soil Region of Southern China

2019 ◽  
Vol 11 (11) ◽  
pp. 3103
Author(s):  
Dong Huang ◽  
Xiaohuan Yang ◽  
Hongyan Cai ◽  
Zuolin Xiao ◽  
Dongrui Han
Keyword(s):  
Soil Erosion ◽  
Human Impact ◽  
Human Impacts ◽  
Southern China ◽  
Red Soil ◽  
Jiangxi Province ◽  
Negative Effects ◽  
Gravity Center ◽  
Local Conditions ◽  
Spatial Differences

Soil erosion (SE) processes are closely related to natural conditions and human activities, posing a threat to environment and society. Identifying the human impact on regional SE changes is increasingly essential for pertinent SE management. Jiangxi province is studied here as a representative area of hilly-red-soil regions within southern China. The main objectives of this study were to investigate the changing trend of SE within Jiangxi and identify human impacts on regional SE change from the perspective of spatial differences, through a new approach based on a gravity-center model. Our results showed that SE status presented an overall amelioration from 1990 to 2015, while the average soil erosion modulus (SEM) declined from 864 to 281 Mg/(km2·a). Compared to the situation under human and natural impacts, human-induced spatial differences of SE change demonstrated that the western and northwest regions showed stronger negative effects; the southern region shifted towards negative effects; the northeast region presented a much weaker negative effect. Our results indicated that 4 cities with strong negative effects need more attention in further SE management suited to their local conditions and development, and also suggested that the approach based on a gravity-center has potential for identifying the human impact on regional SE change from the perspective of spatial patterns.

scholarly journals The Past, Present, and Future of Tuna at Lake Moāwhitu: Drawing on the two knowledge baskets of Mātauranga Māori and Western Science

2021 ◽  
Author(s):  
Russleigh Parai
Keyword(s):  
Algal Blooms ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Land Use Changes ◽  
Environmental Dna ◽  
Western Science ◽  
Lake Water Quality ◽  
Dna Metabarcoding ◽  
Remedial Intervention ◽  
Life Force

<p><b>Knowledge generated through experience and understanding relies on the senses, one of which is listening. This thesis provides an opportunity to hear the diminishing voice of tuna utilizing paleolimnological techniques and our natural senses through traditional Indigenous methodologies in order to track the presence of tuna back in time. </b></p> <p>This study provides historical environmental context of Lake Moāwhitu catchment (Rangitoto ki te Tonga) as a once significant mahinga kai site for manawhenua, Ngāti Koata. The strong connection to place is not lost on Ngāti Koata despite for many their geographic detachment to their turangawaewae. They hear the voice of tuna calling them back to sustain them as they have sustained Māori from the beginning of time. Now considered wāhi tapu due to significant degradation, Moāwhitu is currently undergoing remedial intervention by Ngāti Koata, DoC, Lakes380 and stakeholders to restore the mauri (life force) of the Lake and adjacent wetland ecosystem.</p> <p>Drawing from two distinct knowledge streams of western science and mātauranga Māori, this study draws new (on-site) understandings about the anthropogenic impacts on tuna as well as their status and relationship as tuākana (older sibling) to Māori. Through this journey a ‘te ao Māori’ (Māori worldview) is explored, revealing a historically healthy and abundant tuna population and thriving tuākana-teina relationship up until recent decades. This information complements the environmental reconstruction derived from western science methods applied to a lake Moawhitu sediment core spanning the last 1000 years or so. Through a combination of palynology, hyperspectral scanning and bacterial environmental DNA metabarcoding, it is clear that lake water quality remained high despite various historical land cover and land use changes, until recent decades when deteriorating quality has accompanied a rise in cyanobacteria and toxic algal blooms. These changes appear to coincide with intensified pastoralism accompanying draining of the lake and fringing wetlands since the mid-twentieth century. How tuna have endured these recent human impacts and why their survival and sustainability is important to Aotearoa today is at the heart of this thesis which seeks to explore how two vastly different knowledge streams converge and navigate unchartered waters. The two knowledge baskets (with their respective world views) are held up for the reader to view and consider what an effective collaborative partnership looks like by recognising basic intrinsic values of respect, reciprocity and kindness. The challenge remains to draw out the very best of people (he tangata) as a way to bring about urgent regenerative solutions for our tuākana, tuna, and in turn humanity itself.</p>

scholarly journals Towards Conservation of Genetic Variation of Tropical Tree Species With Differing Successional Status: The Case of Mansonia altissima A. Chev and Triplochiton scleroxylon K. Schum

2019 ◽  
Vol 12 ◽  
pp. 194008291986426
Author(s):  
Akin Akinnagbe ◽  
Oliver Gailing ◽  
Reiner Finkeldey ◽  
Amadu Lawal
Keyword(s):  
Genetic Diversity ◽  
Human Impact ◽  
Tree Species ◽  
Human Impacts ◽  
Genetic Erosion ◽  
Primary Forest ◽  
Timber Species ◽  
Pioneer Species ◽  
Forest Patch ◽  
Successional Status

Two important West African timber tree species with differing successional status, Mansonia altissima A. Chev and Triplochiton scleroxylon K. Schum were investigated in this study. Triplochiton scleroxylon is a pioneer species found in open forests, whereas Mansonia altissima is a nonpioneer light-demanding tree species occurring in closed forests. Amplified fragment length polymorphism markers were used to compare the genetic diversities of these two timber species in stands with different degrees of human impact (isolated forest patch, logged forest, farmland, plantation, and primary forest). Contrasting effects of human impact on genetic diversity were detected for these two timber species. The results suggested severe effects of human impact on the genetic diversity of Mansonia altissima, a nonpioneer species. However, no adverse effect was recorded in Triplochiton scleroxylon, a pioneer species. These findings indicate that nonpioneer tree species could be more prone to genetic erosion than pioneer tree species as a result of adverse human impacts. Therefore, conservation of genetic diversity in both pioneer and nonpioneer tree species populations would likely necessitate different measures.

scholarly journals Komposisi Larva Ikan Pada Tutupan Padang Lamun di Perairan Prawean Bandengan, Kabupaten Jepara

2019 ◽  
Vol 8 (2) ◽  
pp. 96
Author(s):  
Sri Redjeki ◽  
Riska Novianti Putri ◽  
Adi Santoso ◽  
Sunaryo Sunaryo ◽  
Sri Sedjati
Keyword(s):  
Environmental Changes ◽  
Fish Larvae ◽  
Diversity Index ◽  
Mesh Size ◽  
Sampling Location ◽  
Seagrass Beds ◽  
Purposive Sampling ◽  
Distribution Index ◽  
Seagrass Ecosystems ◽  
Distribution Of Fish

Larva Ikan (ichtyoplankton) merupakan tahapan awal dari daur hidup ikan dimulai dari perkembangan telur, larva dan juvenil, memiliki tingkat mortalitas tinggi dan peka terhadap perubahan lingkungan, predator, dan kesediaan makanan. Fungsi ekologis padang lamun sebagai daerah asuhan dan tempat berlindung bagi semua jenis organisme laut kecil, salah satunya larva ikan. Kerapatan atau tutupan padang lamun juga sebagai salah satu faktor pendukung melimpahnya organisme dan kekayaan di laut. Tujuan Penelitian ini untuk mengetahui kelimpahan dan distribusi larva ikan yang terdapat pada ekosistem padang lamun, serta mengetahui hubungan kelimpahan larva ikan dengan tutupan padang lamun di Perairan Prawean Bandengan, Jepara. Metode penelitian ini adalah metode deskriptif dengan penentuan lokasi sampling menggunakan  purposive sampling methode. Lokasi penelitian pada 3 stasiun dengan pembagian kerapatan lamun yang berbeda (I = Padat ; II = Sedang ; III = Jarang) dan dilakukan sebanyak 3 kali pengulangan sampling di masing-masing lokasi. Pengambilan sampel larva ikan dilakukan dengan menggunakan larva net  (P = 0,9 m ; L : 0,6m) dengan ukuran mata jaring 800 µm. Hasil penelitian ini ditemukan larva ikan sebanyak 5 famili yaitu Nemipteridae, Gerreidae, Gobiidae, Labridae, dan Mullidae. Famili larva ikan yang paling sering ditemukan adalah Nemipteridae. Rata-rata kelimpahan famili larva ikan pada Stasiun I sebesar 0,419 ind/m3, Stasiun II sebesar 0,205 ind/m3, dan pada stasiun III sebesar 0,069 ind/m3. Nilai rata - rata indeks keanekaragaman termasuk dalam kategori rendah sedang (0,65–1,37), indeks keseragaman larva ikan termasuk dalam kategori rendah-tinggi (0,33-0,65) indeks dominasi larva ikan menunjukan ada yang mendominasi pada tiga stasiun (0,28–0,30) dan indeks sebaran morisita yang dilakukan menunjukan bahwa sebaran larva ikan pada tiga stasiun merata. Fish larvae (ichtyoplankton) are the initial stages of the fish's life cycle starting from the development of eggs, larvae and juveniles, which have a high mortality rate and are sensitive to environmental changes, predators, and food availability. The ecological function of seagrass beds as nurseries and shelter for all types of small marine organisms, one of which is fish larvae. The density or cover of seagrass beds is also one of the supporting factors for the abundance of organisms and wealth in the sea. The purpose of this study was to determine the abundance and distribution of fish larvae found in the seagrass ecosystems, and to determine the relationship of abundance of fish larvae with cover seagrass beds in the waters of Prawean Bandengan, Jepara. This research method is a descriptive method by determining the sampling location using purposive sampling method. The research location was in 3 stations with a different distribution of seagrass density (I = Dense; II = Medium; III = Rare) and carried out 3 times repetition of sampling at each location. Sampling of fish larvae was carried out using larvae net (P = 0,9 m; L: 0,6m) with a mesh size of 800 μm. The results of this reasearch, found fish larvae of 5 families, namely Nemipteridae, Gerreidae, Gobiidae, Labridae, and Mullidae. The most common family of fish larvae was Nemipteridae. The average abundance of fish larvae at Station I was 0,419 ind/m3, Station II was 0,205 ind/m3, and at Station III was 0,069 ind/m3. The average diversity index was included in the low category (0,65 – 1,37), the uniformity index of fish larvae was included in the low-high category (0,33 – 0,65) the fish larvae dominance index shows that there are dominating at three stations (0,28 – 0,30) and the distribution index of distribution (morisita) conducted showed that the distribution of fish larvae at three stations was evenly distributed.

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