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

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.

Author(s):  
Philip James

The focus of this chapter is an examination of the diversity of living organisms found within urban environments, both inside and outside buildings. The discussion commences with prions and viruses before moving on to consider micro-organisms, plants, and animals. Prions and viruses cause disease in plants and animals, including humans. Micro-organisms are ubiquitous and are found in great numbers throughout urban environments. New technologies are providing new insights into their diversity. Plants may be found inside buildings as well as in gardens and other green spaces. The final sections of the chapter offer a discussion of the diversity of animals that live in urban areas for part or all of their life cycle. Examples of the diversity of life in urban environments are presented throughout, including native and non-native species, those that are benign and deadly, and the common and the rare.


2020 ◽  
Vol 12 (19) ◽  
pp. 3226
Author(s):  
Daniel Cunningham ◽  
Paul Cunningham ◽  
Matthew E. Fagan

Global tree cover products face challenges in accurately predicting tree cover across biophysical gradients, such as precipitation or agricultural cover. To generate a natural forest cover map for Costa Rica, biases in tree cover estimation in the most widely used tree cover product (the Global Forest Change product (GFC) were quantified and corrected, and the impact of map biases on estimates of forest cover and fragmentation was examined. First, a forest reference dataset was developed to examine how the difference between reference and GFC-predicted tree cover estimates varied along gradients of precipitation and elevation, and nonlinear statistical models were fit to predict the bias. Next, an agricultural land cover map was generated by classifying Landsat and ALOS PalSAR imagery (overall accuracy of 97%) to allow removing six common agricultural crops from estimates of tree cover. Finally, the GFC product was corrected through an integrated process using the nonlinear predictions of precipitation and elevation biases and the agricultural crop map as inputs. The accuracy of tree cover prediction increased by ≈29% over the original global forest change product (the R2 rose from 0.416 to 0.538). Using an optimized 89% tree cover threshold to create a forest/nonforest map, we found that fragmentation declined and core forest area and connectivity increased in the corrected forest cover map, especially in dry tropical forests, protected areas, and designated habitat corridors. By contrast, the core forest area decreased locally where agricultural fields were removed from estimates of natural tree cover. This research demonstrates a simple, transferable methodology to correct for observed biases in the Global Forest Change product. The use of uncorrected tree cover products may markedly over- or underestimate forest cover and fragmentation, especially in tropical regions with low precipitation, significant topography, and/or perennial agricultural production.


Diversity ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 358
Author(s):  
François Brassard ◽  
Chi-Man Leong ◽  
Hoi-Hou Chan ◽  
Benoit Guénard

The continuous increase in urbanization has been perceived as a major threat for biodiversity, particularly within tropical regions. Urban areas, however, may still provide opportunities for conservation. In this study focused on Macao (China), one of the most densely populated regions on Earth, we used a comprehensive approach, targeting all the vertical strata inhabited by ants, to document the diversity of both native and exotic species, and to produce an updated checklist. We then compared these results with 112 studies on urban ants to illustrate the dual roles of cities in sustaining ant diversity and supporting the spread of exotic species. Our study provides the first assessment on the vertical distribution of urban ant communities, allowing the detection of 55 new records in Macao, for a total of 155 ant species (11.5% being exotic); one of the highest species counts reported for a city globally. Overall, our results contrast with the dominant paradigm that urban landscapes have limited conservation value but supports the hypothesis that cities act as gateways for exotic species. Ultimately, we argue for a more comprehensive understanding of ants within cities around the world to understand native and exotic patterns of diversity.


2006 ◽  
Vol 86 (2) ◽  
pp. 569-589 ◽  
Author(s):  
Nicholas A. Page ◽  
Ronald E. Wall ◽  
Stephen J. Darbyshire ◽  
Gerald A. Mulligan

Heracleum mantegazzianum (giant hogweed) is an invasive alien plant of management concern in southern Canada where it has escaped from horticulture and established and spread in natural, ruderal, and agricultural ecosystems. It poses a threat to natural ecosystems and human health, and is also a weed in agricultural and urban areas. It is a member of the Carrot family (Apiaceae) and is closely related to the native species Heracleum maximum Bartram (cow-parsnip). It is a monocarpic perennial, which generally flowers in its 3rd or 4th year. Large size, leaf shape, dark reddish pigments in patches on stems and petioles, and fruit characteristics readily distinguish H. mantegazzianum from other plants in Canada. It is increasingly common in riparian areas, floodplains, and forest edges in or near urban areas in southwestern British Columbia and southern Ontario. Based on herbarium specimens, H. mantegazzianum was first recorded in Ontario in 1949, British Columbia in 1964, Nova Scotia in 1980, Quebec in 1990, and New Brunswick in 2000. The development of dense stands of H. mantegazzianum can also reduce the richness of native plants. Contact with H. mantegazzianum can cause phytophotodermatitis, a serious skin inflammation caused by UV photo-activation of furanocoumarins present in the sap. Control methods include herbicide application, mechanical cutting, and animal grazing, but strategies to address seed dispersal and re-establishment from dormant seed must also be adopted. Widespread establishment in southern Canada suggests that eradication is unlikely. However, range expansion and rapid population growth can be prevented through strategic management including public education. Key words: Giant hogweed, Heracleum mantegazzianum, Apiaceae, HERMZ, invasive plant, weed biology, furanocoumarins


2014 ◽  
Vol 36 (3) ◽  
pp. 326-335 ◽  
Author(s):  
Tatiana Carvalho de Castro ◽  
Claudia Simões-Gurgel ◽  
Ivan Gonçalves Ribeiro ◽  
Marsen Garcia Pinto Coelho ◽  
Norma Albarello

The genus Cleome is widely distributed in drier areas of the tropics and subtropics. Cleome dendroides and C. rosea are Brazilian native species that occur mainly in Atlantic Forest and sandy coastal plains, respectively ecosystems negatively affected by human impacts. Cleome spinosa is frequently found in urban areas. Many Cleome species have been used in traditional medicine, as C. spinosa. In the present work, was investigated C. dendroides, C. rosea and C. spinosa germinative behavior under in vivo conditions, as well as was established suitable conditions to in vitro germination and seedling development. The in vivo germination was performed evaluating the influence of temperature, substrate and light. It was observed that only C. spinosa seeds presents physiological dormancy, which was overcome by using alternate temperatures. The substrate influenced significantly the germination of C. rosea and the seeds of C. dendroides showed the highest germination percentages in the different conditions evaluated. The post-seminal development stages under in vivo and in vitro conditions were defined. It was observed that the development was faster under in vitro than in vivo conditions. An effective methodology for in vitro germination, enabling the providing of material to experiment on plant tissue culture was established to C. dendroides and C. spinosa.


2017 ◽  
Vol 65 (4) ◽  
pp. 217 ◽  
Author(s):  
Andy Darmawan ◽  
Tri Atmowidi ◽  
Wasmen Manalu ◽  
Bambang Suryobroto

The conversion of natural forest to agroforestry plantations and annual cropping systems alters the soil habitat and food resources for biota, including earthworms. Native earthworm species may disappear whereas exotic species with greater tolerance of disturbance and less niche specialisation may thrive. The objective of the study was to compare the earthworm diversity in managed forest and agroforestry systems, which were cultivated for mixed plantation and annual crop production on Mount Gede, Indonesia. All the habitats in the study area were impacted by humans. The forest habitat was a managed forest, with a permanent tree cover, whereas mixed plantation had a partial shrub cover. Meanwhile, homogenous plantation was cultivated with annual crops. Among 3787 individuals collected during July–October 2012, five Oriental earthworm species were identified in the soil communities of Mount Gede: Drawida nepalensis, Notoscolex javanica, Pheretima pura-group, Polypheretima moelleri, and Polypheretima sempolensis. Also, 18 species were found that are reported to be non-Oriental in origin. Anthropogenic disturbance of forests on Mount Gede, due to conversion into plantations, alters the earthworm environment by increasing soil water content, temperature and total phosphorous content, while decreasing organic carbon. N. javanica was the only native species to survive this deforestation, while the exotic Ocnerodrilus occidentalis and Pontoscolex corethrurus thrived, becoming the eudominant species. From the forest area to the mixed and homogenous plantations, the predicted decreasing diversity is evidenced by the lowering trend of Shannon’s diversity index. In conclusion, the land-use change into mixed plantations and annual croplands has reduced earthworm diversity in this region of Mount Gede, Indonesia.


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 ◽  
...  

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.


2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Ananto Triyogo ◽  
Budiadi ◽  
Siti Muslimah Widyastuti ◽  
Sena Adi Subrata ◽  
Suwito Susetyo Budi

Abstract. Triyogo A, Budiadi, Widyastuti SM, Subrata SA, Budi SS. 2020. Abundance of ants (Hymenoptera: Formicidae) and the functional groups in two different habitats. Biodiversitas 21: 2079-2087. Land development often affects the quantity and diversity of ants (Hymenoptera: Formicidae). The aim of this study, therefore, was to determine and compare the ant species abundance and the functional groups between two different habitats, representing land development, including pioneer and agroforestry. This research involved a survey of the ants at the Forest Research Education (FRE) of Wanagama I Yogyakarta, and data were accumulated over a period of five months (April, May, June, July, and August). In addition, pit-fall trap and direct collection methods were used, involving the placement of 54 pit-fall traps at two habitats, and the ant specimens were retrieved after a two day period. The results show the total individual abundance of 2,310 and 2,067, on agroforestry and pioneer, respectively. Furthermore, the species richness and diversity index was higher in agroforestry (7; 2.01), compared with pioneer (6; 1.49), where the three dominant species include, Anoplolepis gracilipes, Solenopsis sp., Odontoponera denticulata; and Anoplolepis gracilipes, Odontoponera denticulata, Camponotus sp., respectively. Conversely, the highest amount of invasive ants (Solenopsis sp.) was observed in agroforestry, which negatively impacted on the presence of native species (Odontoponera denticulata). In addition, PCA analysis showed the development of three ant groups on each habitat, hence agroforestry made more real differences in the aspect of species abundance, and none in terms of richness. Therefore, notable differences were observed in the ant communities between both habitats, and agroforestry was indicated as a disturbed area, based on the increment in tramp and invasive ants, alongside low abundance of native and functional groups.


2020 ◽  
Vol 21 (11) ◽  
pp. 2473-2486
Author(s):  
Tirthankar Roy ◽  
Xiaogang He ◽  
Peirong Lin ◽  
Hylke E. Beck ◽  
Christopher Castro ◽  
...  

AbstractWe present a comprehensive global evaluation of monthly precipitation and temperature forecasts from 16 seasonal forecasting models within the NMME Phase-1 system, using Multi-Source Weighted-Ensemble Precipitation version 2 (MSWEP-V2; precipitation) and Climate Research Unit TS4.01 (CRU-TS4.01; temperature) data as reference. We first assessed the forecast skill for lead times of 1–8 months using Kling–Gupta efficiency (KGE), an objective performance metric combining correlation, bias, and variability. Next, we carried out an empirical orthogonal function (EOF) analysis to compare the spatiotemporal variability structures of the forecasts. We found that, in most cases, precipitation skill was highest during the first lead time (i.e., forecast in the month of initialization) and rapidly dropped thereafter, while temperature skill was much higher overall and better retained at higher lead times, which is indicative of stronger temporal persistence. Based on a comprehensive assessment over 21 regions and four seasons, we found that the skill showed strong regional and seasonal dependencies. Some tropical regions, such as the Amazon and Southeast Asia, showed high skill even at longer lead times for both precipitation and temperature. Rainy seasons were generally associated with high precipitation skill, while during winter, temperature skill was low. Overall, precipitation forecast skill was highest for the NASA, NCEP, CMC, and GFDL models, and for temperature, the NASA, CFSv2, COLA, and CMC models performed the best. The spatiotemporal variability structures were better captured for precipitation than temperature. The simple forecast averaging did not produce noticeably better results, emphasizing the need for more advanced weight-based averaging schemes.


Author(s):  
Alena Dostálová ◽  
Markus Hollaus ◽  
Milutin Milenković ◽  
Wolfgang Wagner

The recently launched Sentinel-1A provides the high resolution Synthetic Aperture Radar (SAR) data with very high temporal coverage over large parts of European continent. Short revisit time and dual polarization availability supports its usability for forestry applications. The following study presents an analysis of the potential of the multi-temporal dual-polarization Sentinel-1A data for the forest area derivation using the standard methods based on Otsu thresholding and K-means clustering. Sentinel-1 data collected in winter season 2014-2015 over a test area in eastern Austria were used to derive forest area mask with spatial resolution of 10m and minimum mapping unit of 500&thinsp;m<sup>2</sup>. The validation with reference forest mask derived from airborne full-waveform laser scanning data revealed overall accuracy of 92&thinsp;% and kappa statistics of 0.81. Even better results can be achieved when using external mask for urban areas, which might be misclassified as forests when using the introduced approach based on SAR data only. The Sentinel-1 data and the described methods are well suited for forest change detection between consecutive years.


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