scholarly journals Anthropogenic landscape decreases mosquito biodiversity and drives malaria vector proliferation in the Amazon rainforest

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245087
Author(s):  
Leonardo Suveges Moreira Chaves ◽  
Eduardo Sterlino Bergo ◽  
Jan E. Conn ◽  
Gabriel Zorello Laporta ◽  
Paula Ribeiro Prist ◽  
...  
Keyword(s):  
Landscape Structure ◽  
Linear Mixed Model ◽  
Diversity Index ◽  
Abiotic Factors ◽  
Malaria Risk ◽  
Malaria Vectors ◽  
Human Landing Catch ◽  
Edge Density ◽  
Rural Landscapes ◽  
Forest Fringe

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H’) of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H´ and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at β0 = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H’ (β1 = -218; P < 0.001) and PLAND (β1 = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria.

scholarly journals Contribution of landscape metrics to the assessment of scenic quality - the example of the landscape structure plan Havelland/Germany

2009 ◽  
Vol 10 ◽  
pp. 1-17 ◽  
Author(s):  
Helge Herbst ◽  
Michael Förster ◽  
Birgit Kleinschmit
Keyword(s):  
Landscape Metrics ◽  
Landscape Structure ◽  
Environmental Planning ◽  
Diversity Index ◽  
Structural Diversity ◽  
Objective Evaluation ◽  
Landscape Patterns ◽  
Edge Density ◽  
Aesthetic Quality ◽  
Important Indicator

The scenic quality of a landscape is a natural resource that is to be preserved according to German and international law. One important indicator for the evaluation of this value is the structural diversity of the landscape. Although Landscape Metrics (LM) represent a well-known instrument for the quantification of landscape patterns, they are hardly used in applied landscape and environmental planning. This study shows possibilities for the integration of LM into a commonly used method to assess scenic quality by the example of a Landscape Structure Plan. First results indicate that especially Shannon's Diversity Index and Edge Density are suitable to achieve an objective evaluation of the structural diversity as indicator for scenic quality. The addition of qualitative parameters to the objective structural analysis is discussed. Moreover, the use of landscape scenery units and raster cells as basic geometry has been compared. It shows that LM can support the evaluation of the aesthetic quality in environmental planning, especially when integrated into commonly used evaluation methods.

scholarly journals Landscape structure affects the sunflower visiting frequency of insect pollinators

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Károly Lajos ◽  
Ferenc Samu ◽  
Áron Domonkos Bihaly ◽  
Dávid Fülöp ◽  
Miklós Sárospataki
Keyword(s):  
Landscape Structure ◽  
Honey Bees ◽  
Agricultural Landscape ◽  
Edge Density ◽  
Wild Bees ◽  
Natural Habitats ◽  
Mass Flowering ◽  
Positive Effects ◽  
Pollinator Community ◽  
Foraging Ranges

AbstractMass-flowering crop monocultures, like sunflower, cannot harbour a permanent pollinator community. Their pollination is best secured if both managed honey bees and wild pollinators are present in the agricultural landscape. Semi-natural habitats are known to be the main foraging and nesting areas of wild pollinators, thus benefiting their populations, whereas crops flowering simultaneously may competitively dilute pollinator densities. In our study we asked how landscape structure affects major pollinator groups’ visiting frequency on 36 focal sunflower fields, hypothesising that herbaceous semi-natural (hSNH) and sunflower patches in the landscape neighbourhood will have a scale-dependent effect. We found that an increasing area and/or dispersion of hSNH areas enhanced the visitation of all pollinator groups. These positive effects were scale-dependent and corresponded well with the foraging ranges of the observed bee pollinators. In contrast, an increasing edge density of neighbouring sunflower fields resulted in considerably lower visiting frequencies of wild bees. Our results clearly indicate that the pollination of sunflower is dependent on the composition and configuration of the agricultural landscape. We conclude that an optimization of the pollination can be achieved if sufficient amount of hSNH areas with good dispersion are provided and mass flowering crops do not over-dominate the agricultural landscape.

scholarly journals Assessment of Tuscany Landscape Structure According to the Regional Landscape Plan Partition

2021 ◽  
Vol 13 (10) ◽  
pp. 5424
Author(s):  
Martina Venturi ◽  
Francesco Piras ◽  
Federica Corrieri ◽  
Beatrice Fiore ◽  
Antonio Santoro ◽  
...  
Keyword(s):  
Landscape Structure ◽  
Agricultural Landscapes ◽  
Edge Density ◽  
Regional Government ◽  
Land Uses ◽  
Landscape Mosaic ◽  
Landscape Complexity ◽  
Economic Role ◽  
Patch Density ◽  
Landscape Units

The landscape is considered a strategic asset by the Tuscan regional government, also for its economic role, meaning that a specific Landscape Plan has been developed, dividing the region into 20 Landscape Units and representing the main planning instrument at the regional level. Following the aims of the Landscape Plan and the guidelines of the European Landscape Convention, it is necessary to develop an adequate assessment of the landscape, evaluating the main typologies and their characteristics. The aim of this research is to carry out an assessment of the landscape diversity in Tuscany based on 20 study areas, analyzing land uses and landscape mosaic structures through the application of landscape metrics: number of land uses, mean patch size (MPS), Hill’s diversity number, edge density (ED), patch density (PD), land use diversity (LUD). The results highlight a correlation between the landscape typologies (forest, agricultural, mixed, periurban) and the complexity of the landscape structure, especially in relation to MPS and PD, while the combination of PD and LUD calculated on the basis of a hexagonal grid allows obtaining landscape complexity maps. Despite the phenomena of reforestation and urban sprawl of recent decades, Tuscany still preserves different landscape typologies characterized by a good level of complexity. This is particularly evident in mixed landscapes, while agricultural landscapes have a larger variability because of different historical land organization forms. The methodology applied in this study provided a large amount of data about land uses and the landscape mosaic structure and complexity and proved to be effective in assessing the landscape structure and in creating a database that can represent a baseline for future monitoring.

scholarly journals KEANEKARAGAMAN DAN KEKERABATAN IKAN FAMILI CYPRINIDAE PADA EKOSISTEM BENDUNGAN COLO SUKOHARJO JAWA TENGAH

2018 ◽  
Vol 14 (2) ◽  
pp. 137
Author(s):  
Ragil Nur Cahyono ◽  
Agung Budiharjo ◽  
Sugiyarto Sugiyarto
Keyword(s):  
Fish Species ◽  
Diversity Index ◽  
Abiotic Factors ◽  
Morphological Characters ◽  
Cluster Method ◽  
Fish Diversity ◽  
Abiotic Factor ◽  
Fish Family ◽  
Water Ecosystem ◽  
Before And After

The Cyprinidae fish family is a family of freshwater fish with the largest number of species and its presence is widespread almost all of the world. The main habitat of this family is the river's ecosystem, river damming changing the environmental conditions between the ecosystems before and after the dam's watergate. Such as Colo Dam that dammed Bengawan Solo River that allegedly affects the diversity of species of Cyprinidae fish. So this study was conducted in order to determine the diversity and kinship of the Cyprinidae fish family in the ecosystem before and after the Colo Dam watergate. Sampling was conducted September-October 2017 at Sukoharjo Colo Dam by Purposive sampling method. Identify fish species used Kottelat identification books. The diversity of fish species was calculated by Shannon Wiener's diversity index. The correlation between abiotic factor and fish diversity was analyzed by a regression test. The kinship of the fish was analyzed by the Ntsys cluster method (2.02i). The results showed that the Cyprinidae fish species that live in the Colo Dam ecosystem contain 10 species, the diversity of Cyprinidae fish in the fast-water ecosystem of station I is higher (0,96) then the slow-water ecosystem of station II, III, and IV (0,47; 0,73, and 0,58). Abiotic factors of current velocity affect the level of fish diversity reaches 91%. The Cyprinidae fish kinship rate has a coefficient of resemblance between 60% - 85%, fish with the same genus and many similarities in morphological characters and their behavior is categorized as having a close kinship.

scholarly journals Landscape structure and climate seasonality affect the amount, richness and diversity of pollen collected by honeybees in a Neotropical region of Colombia

2020 ◽  
Author(s):  
Paula María Montoya-Pfeiffer ◽  
Guiomar Nates-Parra
Keyword(s):  
Landscape Structure ◽  
Urban Areas ◽  
Native Species ◽  
Diversity Index ◽  
Forest Area ◽  
Colony Development ◽  
Monthly Precipitation ◽  
Forest Species ◽  
Tropical Regions ◽  
Pollen Species

AbstractPollen is the main food for honeybee broods and young workers and so colony development and reproduction rely heavily on pollen availability, both spatially and temporally, in the environment. Intensification of agriculture and climate seasonality are known to alter honeybee foraging patterns and pollen intake through changes in resource availability in temperate regions; however, little is known about how honeybees respond to such environmental factors in tropical regions.Pollen species collected by honeybees in a Neotropical agricultural region of Colombia were identified. The effects of landscape structure (landscape Shannon Diversity Index, forest area in 1000 m around the apiary) and climate seasonality (mean monthly precipitation) on the amount, richness and diversity of pollen collected by the honeybees were evaluated for all pollen species together and pollen species segregated according to forest and anthropic areas (croplands, grasslands, woodlands, urban areas).Honeybees were found to be much more associated with anthropic than forest pollen species regardless of landscape structure or precipitation. However, the amount, richness and diversity of pollen from all species and forest species responded positively to landscape diversity and forest area, suggesting an advantage for honeybees in obtaining small quantities of pollen from forest species, in spite of being well-adapted to forage in anthropic areas. Precipitation was found not to be related to the overall amount and overall richness of pollen collected by honeybees, suggesting that climate seasonality was not an important factor for pollen foraging. Nonetheless, overall pollen diversity was negatively affected by precipitation in less diverse landscapes, while anthropic pollen diversity was negatively affected in more forested landscapes. These findings are compared with those from temperate regions, and the implications for honeybee productivity and survival, and their interactions with Neotropical native species, are discussed.

scholarly journals Analisis Keanekaragaman Tumbuhan Invasif Di Kawasan Hutan Pantai Balekambang Desa Srigonco Kecamatan Bantur Kabupaten Malang

2020 ◽  
Vol 6 (1) ◽  
pp. 46-53
Author(s):  
Miftahul Mukarromah ◽  
Ari Hayati ◽  
Hasan Zayadi
Keyword(s):  
Invasive Plants ◽  
Invasive Plant ◽  
Cynodon Dactylon ◽  
Diversity Index ◽  
Abiotic Factors ◽  
Coastal Forest ◽  
Mimosa Pudica ◽  
Belt Transect ◽  
Index Value ◽  
Sida Rhombifolia

Balekambang Beach is the most visited beach destination in Malang Regency until the end of 2015. One of the invasive pathways of invasive plants is Tourism. The purpose of this study was to identify invasive plant species, diversity and compare the value of the diversity index with abiotic factors.This research method is descriptive with systematic sampling techniques using Belt Transect, and measurements of abiotic factors include edafic factors and climatic micro factors. Invasive alien plant species found in the Balekambang coastal forest are identified as seventeen species namely (Hemighraphis glaucescens), (Oplismenus sp), (Amomum coccineum), (Arenga obtusifolia), (Leucaena leucochephana), (Mimosa sp), (Cassia siamea), (Eupatorium odoratum), (Hyptis capitata), (Cynodon dactylon), (Sida rhombifolia), (Synedrella nudiflora), (Chromolaena odorata),  (Leucaena leucochepala), (Mimosa pudica), and (Ruellia tuberosa) with the index value of invasive plant diversity in protected forests and production classified as high compared to mangroves. The results of the diversity index value with abiotic factors showed a positive (+) direction on soil sailinity where the R2 value was 0.5606 or 50%, which means it showed a relationship between soil salinity and an abundance of invasive plants in Balekambang coastal forest area of 50%.  Keywords:invasive plants, Balekambang beach, belt transect, diversity ABSTRAK Pantai Balekambang adalah destinasi wisata alam pantai di Kabupaten Malang yang paling banyak dikunjungi hingga akhir tahun 2015.Salah satu jalur invasi dari tumbuhan invasif adalah Tourism (Wisata). Tujuan dari penelitian ini adalah mengidentifikasi jenis tumbuhan invasif, keanekaragaman dan membandingkan nilai indeks keanekaragaman dengan faktor abiotik. Metode penelitian ini deskriptif dengan tehnik pengambilan sampling secara sistematis menggunakan Belt Transect, dan pengukuran faktor abiotik meliputi faktor edafik dan faktor mikro klimatik. Jenis spesies tumbuhan asing invasif yang terdapat di hutan pantai Balekambang diidentifikasi sebanyak tujuh belas spesies yaitu Hemighraphis glaucescens, Oplismenus sp, Amomum coccineum, Arenga obtusifolia, Leucaena leucochephana, Mimosa sp, Cassia siamea, Eupatorium odoratum, Hyptis capitata, Cynodon dactylon, Sida rhombifolia, Synedrella nudiflora.Chromolaena odorata, Leucaena leucochepala, Mimosa pudica, dan Ruellia tuberose dengan nilai indeks keanekaragaman tumbuhan invasif pada hutan lindung dan produksi tergolong tinggi dibanding mangrove. Hasil analisis uji korelasi nilai indeks keanekaragaman dengan faktor abiotik menunjukkan arah positif (+) pada salinitas tanah dimana nilai R2 sebesar 0.5606 atau 50%, yang artinya menunjukkan hubungan antara salinitas tanah dengan kelimpahan tumbuhan invasif di kawasan hutan pantai Balekambang sebesar 50%. Kata kunci: tumbuhan invasif, pantai Balekambang, belt transect, keanekaragaman

Effect of Urban Fringes Green Space Fragmentation on Ecosystem Service Value

2021 ◽  
Author(s):  
Yingying Guan ◽  
Xueming Li ◽  
Jun Yang ◽  
Songbo Li ◽  
He Liu
Keyword(s):  
Correlation Coefficient ◽  
Ecosystem Service ◽  
Green Space ◽  
Diversity Index ◽  
Arable Land ◽  
Edge Density ◽  
Ecosystem Service Value ◽  
Aggregation Index ◽  
Large Plaque ◽  
Service Value

Abstract In this study, an urban fringe green space classification system was established to explore the spatiotemporal variation of green space landscape and ecosystem service value (ESV) based on multi-source land-use data of Ganjingzi district from 2000 to 2018. (1) Results show that the total green space area declined from 359.57 to 213.46 km 2 over the study period. Green space large plaque index (LPI) and class area both gradually declined, whereas the number of plaques (NP) and plaque density (PD) gradually increased, indicating green space landscape fragmentation. (2) Additionally, the value of green space ecosystem services reduced from 397.42 to 124.93 million yuan. The dynamic degree of ESV change in green space increased or decreased moderately, always being < 0 and showing a decreasing trend of ESV. From a spatial variation perspective, dynamic degrees of ESV variation in the western and northern regions with relatively intensive green space were higher than those in the east. Regarding ESV of various green space types, forest land had the highest functional values of ecological regulation and support, whereas arable land provided the highest functional values of production supply. (3) The ecological service function value of green space system is negatively correlated with PD, NP, edge density, landscape shape index, and Shannon’s diversity index, and positively correlated with aggregation index, contagion metrics, and LPI. The correlation coefficient between the climate regulation function of forest and the change of number of plaques is -0.874. The correlation coefficient of the recreation and culture of the wetland to the plaque density change is no less than -0.214.

scholarly journals Landscape Transformations in Rapidly Developing Peri-urban Areas of Accra, Ghana: Results of 30 years

2019 ◽  
Vol 11 (1) ◽  
pp. 172-182 ◽  
Author(s):  
George Ashiagbor ◽  
Clifford Amoako ◽  
Stephen B. Asabere ◽  
Jonathan A. Quaye-Ballard
Keyword(s):  
Landscape Structure ◽  
Urban Areas ◽  
Urban Governance ◽  
Urban Landscape ◽  
Urban Expansion ◽  
Edge Density ◽  
Aggregation Index ◽  
Intensity Index ◽  
Landsat Satellite ◽  
Landscape Transformations

Abstract Beyond the loss of peri-urban agricultural and forested land as a result of built-up expansion, not much information exists on the changes in the structure of the peri-urban landscape in Ghana. The aim of this paper is to examine the extent to which urban expansion is driving changes in landscape structure of the peri-urban fringes of Accra. We submit that rapid peri-urbanisation will fragment the existing agricultural and forested landscape with consequent ecological, socio-economic and urban governance implications. Using Landsat satellite images for the years 1985, 1991, 2002 and 2015 the study area was classified into four land cover classes. The study adopted the use of Urban Intensity Index (UII) and the Annual Rate of Urbanization (R) as measures of urbanization. Edge density (ED), largest patch index (LPI) and Aggregation index (AI) were used as proxies to measure landscape structural transformations. The study reveals substantial reductions and fragmentation in agricultural lands, riverine and open forests, while there has been over 200 percent increase in built-up areas. Beyond these revelations in spatiotemporal changes in landscape structure, the paper points to the ecological implications of the changes, and three key socio-economic and urban governance implications.

scholarly journals ANALYZING LAND USE PATTERN CHANGES IN MUKIM PENGERANG, JOHOR, MALAYSIA

2018 ◽  
Vol 5 (2) ◽  
pp. 229
Author(s):  
Noordini Binti Che Man ◽  
Anis Farhan Binti Salihin
Keyword(s):  
Land Use ◽  
Diversity Index ◽  
Rapid Development ◽  
Urban Land Use ◽  
Ecological Impacts ◽  
Landscape Patterns ◽  
Edge Density ◽  
Spatiotemporal Pattern ◽  
Land Use Pattern ◽  
Use Pattern

Urbanization and urban land-use transition have a competitive environment to ensure and provide good facilities for citizen benefit. The landscape patterns resulting from urbanization effect processes at local, regional, and global scales. Quantifying the spatiotemporal pattern of urbanization is important for understanding its ecological impacts and can provide basic information for appropriate decision-making. The growth of urbanization in Mukim Pengerang, Johor, has undergone rapid changes in agriculture, settlements, townships and various activities. The changes of land use take place in Mukim Pengerang due to the rapid economic development, especially in industrializations which are Refinery and Petrochemical Integrated Development (RAPID) project and Pengerang Integrated Petroleum Complex (PIPC). The industrialization boosts the growth in land property and commercial which progressing in rapid development since the year 2012, in resulting whether it can give good, bad or both impact to the human and surrounding. Therefore, the main aim of this paper is to quantify the changes in landscape pattern or land use pattern between the year 2008 and 2017 occurred in Mukim Pengerang. In monitoring the spatial pattern changes, and the changes of landscape structure, the metrics landscape were analyzed with determination of the Shanon Diversity Index (SHDI), the number of patches (NP), Edge Density (ED) and Total Edge (TE) in the period of 8 years. The results show that the changes occurred with the three types of land use showed significant changes in the types of land use which are forest, agricultural and built-up area. The result of SHDI analysis shows the increment value between the year 2008 and 2017. This situation illustrates that the higher value of SHDI for an area, resulting in the higher level of land use. This is because the growing pattern of land use is reflected by a large number of patches due to the diversification of land use activities in the area. As a result, from the metrics statistics test verifies there was a significant change in land use that took place within 8 years.

scholarly journals Evaluation of mosquito electrocuting traps as a safe alternative to the human landing catch for measuring human exposure to malaria vectors in Burkina Faso

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Antoine Sanou ◽  
W. Moussa Guelbéogo ◽  
Luca Nelli ◽  
K. Hyacinth Toé ◽  
Soumanaba Zongo ◽  
...  
Keyword(s):  
Species Composition ◽  
Burkina Faso ◽  
Malaria Vector ◽  
Human Exposure ◽  
Infected Mosquito ◽  
Malaria Vectors ◽  
Human Landing Catch ◽  
Mosquito Vector ◽  
Human Landing ◽  
Biting Behaviour

Abstract Background Measuring human exposure to mosquito bites is a crucial component of vector-borne disease surveillance. For malaria vectors, the human landing catch (HLC) remains the gold standard for direct estimation of exposure. This method, however, is controversial since participants risk exposure to potentially infected mosquito bites. Recently an exposure-free mosquito electrocuting trap (MET) was developed to provide a safer alternative to the HLC. Early prototypes of the MET performed well in Tanzania but have yet to be tested in West Africa, where malaria vector species composition, ecology and behaviour are different. The performance of the MET relative to HLC for characterizing mosquito vector population dynamics and biting behaviour in Burkina Faso was evaluated. Methods A longitudinal study was initiated within 12 villages in Burkina Faso in October 2016. Host-seeking mosquitoes were sampled monthly using HLC and MET collections over 14 months. Collections were made at 4 households on each night, with METs deployed inside and outside at 2 houses, and HLC inside and outside at another two. Malaria vector abundance, species composition, sporozoite rate and location of biting (indoor versus outdoor) were recorded. Results In total, 41,800 mosquitoes were collected over 324 sampling nights, with the major malaria vector being Anopheles gambiae sensu lato (s.l.) complex. Overall the MET caught fewer An. gambiae s.l. than the HLC (mean predicted number of 0.78 versus 1.82 indoors, and 1.05 versus 2.04 outdoors). However, MET collections gave a consistent representation of seasonal dynamics in vector populations, species composition, biting behaviour (location and time) and malaria infection rates relative to HLC. As the relative performance of the MET was somewhat higher in outdoor versus indoor settings, this trapping method slightly underestimated the proportion of bites preventable by LLINs compared to the HLC (MET = 82.08%; HLC = 87.19%). Conclusions The MET collected proportionately fewer mosquitoes than the HLC. However, estimates of An. gambiae s.l. density in METs were highly correlated with HLC. Thus, although less sensitive, the MET is a safer alternative than the HLC. Its use is recommended particularly for sampling vectors in outdoor environments where it is most sensitive.

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