Relationships between gregarine infection in damselflies, wetland type, and landscape characteristics

2011 ◽  
Vol 143 (5) ◽  
pp. 460-469 ◽  
Author(s):  
Julia J. Mlynarek ◽  
Daniel G. Bert ◽  
G. Haydeé Peralta-Vázquez ◽  
Joanna A. James ◽  
Mark R. Forbes
Keyword(s):  
Forest Cover ◽  
Road Density ◽  
Natural Habitats ◽  
Artificial Wetlands ◽  
Wetland Type ◽  
Landscape Characteristics ◽  
Natural Wetlands ◽  
Ischnura Verticalis ◽  
Host Parasite ◽  
Wetland Cover

AbstractAlthough human-modified landscapes are characterized by the loss of natural habitats, new habitats also can be created and exploited by many species. The importance of landscape change to invertebrate associations (particularly host-parasite associations) is understudied. Our objective was to determine whether prevalence and intensity of gregarine parasitism in the damselfly Ischnura verticalis (Say) (Odonata: Coenagrionidae) differed between 17 artificial and 7 natural wetlands in landscapes that varied in amount of forest and wetland cover and road density determined at spatial extents of 500m and 1km from each wetland. Wetlands were located in and around Ottawa, Ontario, and Gatineau, Quebec, Canada. Wetland type did not account for significant variation in principal components based on forest and wetland cover and road density at either spatial extent. Gregarine prevalence was higher in damselflies collected from natural wetlands than in those collected from artificial wetlands and was positively associated with increasing forest cover. In contrast, gregarine intensity was inversely related to road density. Our results suggest that parasitism of damselflies by gregarines is associated with wetland type and landscape characteristics, although the mechanisms producing such relationships are unknown.

scholarly journals A Study of Forest Swamp Mapping in Hani Wetland Integrating Sentinel-1 and Sentinel-2 Satellite Images

2021 ◽  
Author(s):  
Jingfa Wang
Keyword(s):  
Information Extraction ◽  
Optimal Number ◽  
Kappa Coefficient ◽  
Artificial Wetlands ◽  
Wetland Type ◽  
Red Edge ◽  
International Importance ◽  
Natural Wetlands ◽  
Landscape Types ◽  
Sentinel 2

As a unique wetland type, forest swamps play an important role in regional carbon cycling and biodiversity conservation. Taking Hani wetland in Jilin province as the research object, we integrated the application of Sentinel-1 radar and Sentinel-2 multispectral images, fully exploited the potential of Sentinel-1 multi-polarization band features and Sentinel-2 red edge index for forest swamp remote sensing identification, and applied the random forest method to realize the extraction of forest swamp distribution information of Hani wetland. The results show that when the optimal number of decision trees for forest swamp information extraction is 1200, the fusion of Sentinel-1VV and VH backscattering coefficient radar band features and Sentinel-2 red-edge band features can significantly improve the extraction accuracy of forest swamp distribution information, and the overall accuracy and Kappa coefficient of forest swamp information extraction in protected areas are as high as 89% and 0.85, respectively. The overall accuracy and Kappa coefficient of forest swamp information extraction in the protected area were 89% and 0.85, respectively. The landscape types of Hani Wetlands of International Importance are diversified, with natural wetlands, artificial wetlands and non-wetland landscape types co-existing. Among the natural wetland types, the forest swamp has the largest area of 27.1 km2, accounting for 11.2% of the total area of the reserve; the river has the smallest area of 0.7 km2, accounting for 0.3% of the total area of the reserve. The forest swamp extraction method provides data support for the sustainable management of Hani wetlands and case guidance for forest swamp mapping in other regions.

scholarly journals Landscape Characteristics and Ecological Risk Assessment Based on Multi-Scenario Simulations: A Case Study of Yancheng Coastal Wetland, China

2020 ◽  
Vol 13 (1) ◽  
pp. 149
Author(s):  
Peng Tian ◽  
Luodan Cao ◽  
Jialin Li ◽  
Ruiliang Pu ◽  
Hongbo Gong ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Markov Model ◽  
Ecological Risk ◽  
Ecological Risk Assessment ◽  
Coastal Wetland ◽  
Landscape Planning ◽  
Test Accuracy ◽  
Artificial Wetlands ◽  
Wetland Landscape ◽  
Natural Wetlands

Carrying out coastal wetland landscape simulations and current and future ecological risk assessments is conducive to formulating policies for coastal wetland landscape planning and promoting the coordinated development of the social economy and ecological environment. This study used the Cellular Automaton (CA)-Markov model to simulate the landscape data of the study area under different scenarios in 2021 and 2025, and built an ecological risk assessment (ERS) index model to analyze the differences of spatio-temporal characteristics of ecological risks. The results showed that: (1) The test accuracy of the CA–Markov model was 0.9562 after passing through the consistency test. The spatial distribution data of landscapes under current utilization scenarios (CUSs), natural development scenarios (NDSs), and ecological protection scenarios (EPSs) were gained through simulations. (2) During 1991–2025, the landscape types of Yancheng coastal wetlands undertake complicated transfers and have vast transfer regions. Under CUSs and NDSs, a large number of natural wetlands are transferred to artificial wetlands. Under EPSs, the area of artificial wetlands declines and artificial wetlands are mainly transferred to natural wetlands. (3) The ecological risk of Yancheng Coastal Wetland increases, accompanied with significant spatial heterogeneity, which is manifested as low in the north area and high in the south area, and there exist some differences between sea areas and land areas. Ecological risk levels transfer violently.

scholarly journals Association between wetland presence and incidence of Salmonella enterica serotype Javiana infections in selected US sites, 2005–2011

2017 ◽  
Vol 145 (14) ◽  
pp. 2991-2997 ◽  
Author(s):  
J. Y. HUANG ◽  
M. E. PATRICK ◽  
J. MANNERS ◽  
A. R. SAPKOTA ◽  
K. J. SCHERZINGER ◽  
...  
Keyword(s):  
Active Surveillance ◽  
Salmonella Enterica ◽  
Regional Differences ◽  
Incidence Rates ◽  
Foodborne Disease ◽  
Surveillance Network ◽  
Wetland Type ◽  
The Usa ◽  
The Relationship ◽  
Wetland Cover

SUMMARYSalmonella causes an estimated 1·2 million illnesses annually in the USA. Salmonella enterica serotype Javiana (serotype Javiana) is the fourth most common serotype isolated from humans, with the majority of illnesses occurring in southeastern states. The percentage of wetland cover by wetland type and the average incidence rates of serotype Javiana infection in selected counties of the Foodborne Disease Active Surveillance Network (FoodNet) were examined. This analysis explored the relationship between wetland environments and incidence in order to assess whether regional differences in environmental habitats may be associated with observed variations in incidence. Findings suggest that environmental habitats may support reservoirs or contribute to the persistence of serotype Javiana, and may frequently contribute to the transmission of infection compared with other Salmonella serotypes.

scholarly journals THE SOCIALIST REPUBLIC OF VIETNAM IN THE INTERNATIONAL MARKETS OF AQUACULTURE PRODUCTS

2021 ◽  
pp. 96-99
Author(s):  
Vladimir Grigor'ev ◽  
Dan Chuong Fam Thi ◽  
Rustam Nizamov ◽  
Igor' Grigor'ev
Keyword(s):  
Forest Cover ◽  
Natural Habitat ◽  
Strong Dependence ◽  
World Market ◽  
Natural Ecosystems ◽  
Natural Conditions ◽  
Natural Habitats ◽  
Socialist Republic ◽  
National University ◽  
The Government

Aquaculture is one of the most promising and dynamically developing types of agricultural production, especially in countries with warm climates. The research was carried out to analyze the current situation in aquaculture in Vietnam to clarify the existing problems and prospects of this industry. When collecting materials, we used statistical data from the Government of the Socialist Republic of Vietnam, as well as information from representatives of the Institute of Economics and Business of the Vietnam National University (Hanoi). In the Socialist Republic of Vietnam, aquaculture is well developed and continues to actively expand, annually increasing the production of products that are in significant demand on the world market. One of the most important problems of the industry is the threat to natural biodiversity, primarily due to the reduction of the natural habitats of the inhabitants of rivers and mangroves. An equally important problem is the strong dependence of the production of products, primarily shrimp, on foreign markets, which today is objective and insurmountable. Due to the use of chemicals and antibiotics in aquaculture, especially in natural conditions, environmental degradation is possible. Among the promising areas for the development of the industry is the convergence of natural ecosystems and agriculture, a good example of which is the cultivation of shrimp in mangroves without destroying the forest cover. It is possible to switch to aquaculture as an adaptation to changes in the ecological situation, primarily to the salinization of river deltas. As a result of a decrease in the profitability of fishing in the natural habitat of fish and shrimps, an increase in their populations in natural conditions is possible

Spatial Model Approach for Deforestation

2013 ◽  
pp. 1901-1912
Author(s):  
Lilik B. Prasetyo ◽  
Chandra Irawadi Wijaya ◽  
Yudi Setiawan
Keyword(s):  
Population Density ◽  
Rural Areas ◽  
Forest Cover ◽  
Positive Impact ◽  
Forest Loss ◽  
Road Density ◽  
Policy Makers ◽  
Explanatory Variables ◽  
The Government ◽  
Negative Impacts

Java is very densely populated since it is inhabited by more than 60% of the total population of Indonesia. Based on data from the Ministry of Forestry, forest loss between 2000-2005 in Java was about 800,000 hectares. Regardless of the debate on whether the different methodologies of forest inventory applied in 2005 have resulted in an underestimation of the figure of forest loss or not, the decrease of forest cover in Java is obvious and needs immediate response. Spatial modeling of the deforestation will assist the policy makers in understanding this process and in taking it into consideration, when decisions are made on the issue. Moreover, the results can be used as data input to solve environmental problems resulting from deforestation. The authors of this chapter modeled the deforestation in Java by using logistic regression. Percentage of deforested area was considered as the response variable, whilst biophysical and socioeconomic factors, that explain the current spatial pattern in deforestation, were assigned as explanatory variables. Furthermore, the authors predicted the future deforestation process, and then, for the case of Java, it was validated with the actual deforestation derived from MODIS satellite imageries from 2000 to 2008. Results of the study showed that the impacts of population density, road density, and slope are significant. Population density and road density have negative impacts on deforestation, while slope has positive impact. Deforestation on Java Island tends to occur in remote areas with limited access, low density population and relatively steep slopes. Implication of the model is that the government should pay more attention to remote rural areas and develop good access to accelerate and create alternative non agricultural jobs in order to reduce pressure on the forest.

Spatial Model Approach for Deforestation

2011 ◽  
pp. 376-387 ◽  
Author(s):  
Lilik B. Prasetyo ◽  
Chandra Irawadi Wijaya ◽  
Yudi Setiawan
Keyword(s):  
Population Density ◽  
Rural Areas ◽  
Forest Cover ◽  
Positive Impact ◽  
Forest Loss ◽  
Road Density ◽  
Policy Makers ◽  
Explanatory Variables ◽  
The Government ◽  
Negative Impacts

Java is very densely populated since it is inhabited by more than 60% of the total population of Indonesia. Based on data from the Ministry of Forestry, forest loss between 2000-2005 in Java was about 800,000 hectares. Regardless of the debate on whether the different methodologies of forest inventory applied in 2005 have resulted in an underestimation of the figure of forest loss or not, the decrease of forest cover in Java is obvious and needs immediate response. Spatial modeling of the deforestation will assist the policy makers in understanding this process and in taking it into consideration, when decisions are made on the issue. Moreover, the results can be used as data input to solve environmental problems resulting from deforestation. The authors of this chapter modeled the deforestation in Java by using logistic regression. Percentage of deforested area was considered as the response variable, whilst biophysical and socioeconomic factors, that explain the current spatial pattern in deforestation, were assigned as explanatory variables. Furthermore, the authors predicted the future deforestation process, and then, for the case of Java, it was validated with the actual deforestation derived from MODIS satellite imageries from 2000 to 2008. Results of the study showed that the impacts of population density, road density, and slope are significant. Population density and road density have negative impacts on deforestation, while slope has positive impact. Deforestation on Java Island tends to occur in remote areas with limited access, low density population and relatively steep slopes. Implication of the model is that the government should pay more attention to remote rural areas and develop good access to accelerate and create alternative non agricultural jobs in order to reduce pressure on the forest.

scholarly journals Management of mountainous meadows associated with biodiversity attributes, perceived health benefits and cultural ecosystem services

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Raja Imran Hussain ◽  
Ronnie Walcher ◽  
Renate Eder ◽  
Brigitte Allex ◽  
Peter Wallner ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Ecosystem Services ◽  
Human Health ◽  
Forest Cover ◽  
Health Benefits ◽  
Perceived Health ◽  
Well Being ◽  
Swiss Alps ◽  
Cultural Ecosystem Services ◽  
Landscape Characteristics

Abstract Associations between biodiversity, human health and well-being have never been discussed with reference to agriculturally managed, species-rich mountainous meadows. We evaluated these associations between extensively managed (one mowing a year, no fertilization) and abandoned (no mowing since more than 80 years, no fertilization) semi-dry meadows located in the Austrian and Swiss Alps. We quantified the richness and abundance of plants, grasshoppers, true bugs, bumblebees, syrphids and landscape characteristics in the surroundings of the meadows. Associations between these biodiversity attributes and short-term psychological and physiological human health effects were assessed with 22 participants (10 males, 12 females; mean age 27 years). Participants´ pulse rate, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were not affected during visits to managed or abandoned meadows. However, perceived health benefits (e.g., stress reduction, attention restoration) were higher during their stays in managed than in abandoned meadows. Also, the attractiveness of the surrounding landscape and the recreation suitability were rated higher when visiting managed meadows. Perceived naturalness was positively correlated with plant richness and flower cover. A positive correlation was found between SBP and forest cover, but SBP was negatively correlated with the open landscape. A negative association was found between grasshoppers and recreational and landscape perceptions. We suggest to discuss biodiversity attributes not only in connection with agricultural management but also with cultural ecosystem services and health benefits to raise more awareness for multifaceted interrelationships between ecosystems and humans.

Influence of land use on fine sediment in salmonid spawning gravels within the Russian River Basin, California

2005 ◽  
Vol 62 (12) ◽  
pp. 2740-2751 ◽  
Author(s):  
Jeff J Opperman ◽  
Kathleen A Lohse ◽  
Colin Brooks ◽  
N Maggi Kelly ◽  
Adina M Merenlender
Keyword(s):  
Land Use ◽  
Land Cover ◽  
River Basin ◽  
Forest Cover ◽  
Multiple Scales ◽  
Explanatory Power ◽  
Fine Sediment ◽  
Road Density ◽  
Watershed Land Use ◽  
Russian River

Relationships between land use or land cover and embeddedness, a measure of fine sediment in spawning gravels, were examined at multiple scales across 54 streams in the Russian River Basin, California. The results suggest that coarse-scale measures of watershed land use can explain a large proportion of the variability in embeddedness and that the explanatory power of this relationship increases with watershed size. Agricultural and urban land uses and road density were positively associated with embeddedness, while the opposite was true for forest cover. The ability of land use and land cover to predict embeddedness varied among five zones of influence, with the greatest explanatory power occurring at the entire-watershed scale. Land use within a more restricted riparian corridor generally did not relate to embeddedness, suggesting that reach-scale riparian protection or restoration will have little influence on levels of fine sediment. The explanatory power of these models was greater when conducted among a subset of the largest watersheds (maximum r2 = 0.73) than among the smallest watersheds (maximum r2 = 0.46).

Amphibian reproductive success as a gauge of functional equivalency of created wetlands in the Central Appalachians

2017 ◽  
Vol 44 (4) ◽  
pp. 354 ◽  
Author(s):  
Gabriel F. Strain ◽  
Philip J. Turk ◽  
Jordan Helmick ◽  
James T. Anderson
Keyword(s):  
Growth Curves ◽  
Wildlife Habitat ◽  
Breeding Habitat ◽  
Wetland Mitigation ◽  
Sufficient Evidence ◽  
Created Wetlands ◽  
Green Frog ◽  
Vegetative Cover ◽  
Wetland Type ◽  
Natural Wetlands

Context Evaluating the adequacy of created wetlands to replace the functions of lost natural wetlands is important because wetland mitigation is a major tool used to offset wetland losses. However, measurements such as vegetative cover and presence of wildlife may not provide sufficient evidence that created wetlands are functioning properly. Thus, examining the ecology of wetland biota such as that of amphibians may be a more useful surrogate for function. Aims The objectives of this study were to compare the abundance of amphibian metamorphs and survival and growth of larval amphibians in created wetlands, relative to natural wetlands. Methods Amphibian metamorphs were trapped in created and natural wetlands during the spring (April–May) and summer (June–August) of 2009 and 2010, and 165 green frog (Lithobates clamitans) larvae were raised during the spring of 2010 in laboratory aquaria containing water from created or natural wetlands. Key results Abundance of spring peeper (Pseudacris crucifer) metamorphs decreased significantly from 2009 to 2010 and abundance of green frog metamorphs increased with habitat complexity, but both were unaffected by wetland type. Detection probability of metamorphs of both species was low, increased with water temperature and declined with month of observation. Survival, growth curves and mass were similar among green frog larvae raised in created and natural wetland aquaria. Conclusions Our results suggest that the created and natural wetlands we examined function similarly with respect to providing adequate breeding habitat for green frogs and spring peepers. Implications Wetlands created to offset the loss of natural wetlands, although generally not designed for the purpose of wildlife habitat, can function as adequate breeding habitat for generalist amphibians such as green frogs and spring peepers.

scholarly journals Multi-scale analysis to uncover habitat use of red-crowned cranes: Implications for conservation

2013 ◽  
Vol 59 (5) ◽  
pp. 604-617 ◽  
Author(s):  
Chunyue Liu ◽  
Hongxing Jiang ◽  
Shuqing Zhang ◽  
Chunrong Li ◽  
Yunqiu Hou ◽  
...  
Keyword(s):  
Habitat Use ◽  
Positive Impact ◽  
Spatial Scales ◽  
Paddy Fields ◽  
Natural Habitats ◽  
Multi Scale ◽  
Aquaculture Ponds ◽  
Natural Wetlands ◽  
Percent Area ◽  
Area Percentage

Abstract A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lacking. We evaluated the effects of several habitat variables quantified across many spatial scales on crane use and abundance in two periods (2000 and 2009) at Yancheng National Nature Reserve, China. The natural wetlands decreased in area by 30,601 ha (-6.9%) from 2000 to 2009, predominantly as a result of conversion to aquaculture ponds and farmland, and the remaining was under degradation due to expansion of the exotic smooth cordgrass. The cranes are focusing in on either larger patches or those that are in close proximity to each other in both years, but occupied patches had smaller size, less proximity and more regular boundaries in 2009. At landscape scales, the area percentage of common seepweed, reed ponds and paddy fields had a greater positive impact on crane presence than the area percentage of aquaculture ponds. The cranes were more abundant in patches that had a greater percent area of common seepweed and reed ponds, while the percent area of paddy fields was inversely related to crane abundance in 2009 due to changing agricultural practices. In 2009, cranes tended to use less fragmented plots in natural wetlands and more fragmented plots in anthropogenic paddy fields, which were largely associated with the huge loss and degradation of natural habitats between the two years. Management should focus on restoration of large patches of natural wetlands, and formation of a relatively stable area of large paddy field and reed pond to mitigate the loss of natural wetlands.

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