scholarly journals Bat-fruit networks structure resist habitat modification but species roles change in the most transformed habitats

2019 ◽  
Author(s):  
John Harold Castaño ◽  
Jaime Andrés Carranza-Quiceno ◽  
Jairo Pérez-Torres

AbstractSpecies do not function as isolated entities, rather they are organized in complex networks of interactions. These networks develop the ecological processes that provide ecosystem services for human societies. Understanding the causes and consequences of changes in ecological networks due to landscape modification would allow us to understand the consequences of ecological processes. However, there is still theoretical controversy and few empirical data on the effects of network characteristics on the loss of natural environments. We investigate how bat–fruit networks respond to three landscapes representing the gradient of modification from pre-montane forest to a heterogeneous agricultural landscape in the Colombian Andes (continuous forests, forest fragments, and crops). We found that forest contained smaller bat–fruit networks than forest fragments and crops. Modified landscapes had similar ecological network structures to forest (nestedness and modularity), but crops contained less specialized networks compared to forests and fragments and the species role in these habitats change. The networks in the rural coffee landscape maintain their structure in the different transformation scenarios, indicating that seed dispersal services are maintained even in the most transformed scenarios. This could be related to the high heterogeneity present in this rural landscape. Although the number of species does not decrease due to transformations, species change their roles in the most transformed habitats. This result sheds light on the way that biodiversity responds to anthropogenic transformations, showing higher stability than theoretically predicted.

2019 ◽  
Author(s):  
B. Adriaan Grobler ◽  
Eileen. E. Campbell

AbstractRoad verges can provide important habitats for plants, especially in transformed landscapes. However, roads and their associated traffic have several adverse impacts on ecosystems that can disrupt vital ecological processes, including pollination. In transformed landscapes, road effects on pollination might be complemented by impacts of large-scale habitat modification. In these landscapes, road verge populations of plants that rely on pollinators for pollen transfer could thus be at risk of pollination failure. This study investigates the pollination of a reseeding, bird-pollinated shrub,Erica glandulosa, in road verges of a fragmented and transformed rural landscape in the southeastern Cape Floristic Region. We test for road impacts on pollination by comparing number of ruptured anther rings—a proxy for pollination—in fynbos vegetation fragments at different distances from the road (0–10, 20–30 and 40–50 m). We also test whether different land-cover types (intact fynbos, alien thickets and rangelands/pastures) next to road verges influence the number of ruptured anther rings. After controlling for robbing rate and plant density, fewer flowers were pollinated near the road than farther away, and fewer flowers were pollinated where road verges occurred next to alien thickets or pastures/rangelands compared to intact fynbos. However, bird pollination was not excluded in road verges: on average, ca. 20–30% of flowers were still visited by birds near the road. These findings potentially call into question the suitability of road verges as refugia for seed-dependent, bird-pollinated plant species in transformed landscapes.


Author(s):  
A. Rolando ◽  
A. Scandiffio

Abstract. The current research aims at exploring the relationships between historical agricultural landscapes and sustainable tourism, by combining the potential of aerial and ground observation methods, that are able to detect the seasonal landscape changes. These phenomena are strongly interlaced with the annual cycle of plants, which have many implications for ecological processes, agriculture, health, tourism, regional/urban planning and economy. In many countries, similar phenomena as the timing of spring-blooming or the timing of autumn coloring foliage are of great visual value and can be of touristic interest, so to enhance the overall attractiveness of a territory. The research analyzes the case study of the historical agricultural landscape, localized in the in-between territories Turin and Milan, which is characterized by large portions of paddy-rice fields, which assume different aesthetical configurations over the year. This landscape, made up of an articulated system of waterways that support large portions of rice cultivation, protected natural areas, historical farmhouses, urban settlements, is the result of a long process of interaction between natural elements and human activities. Remote sensing and ground observations can play an important role in a high-accuracy mapping of the seasonal conditions of this kind of landscape. The flooding of paddy-rice fields determines a high scenic value of large portions of the rural landscape, that can be detected through remote sensing. The specificity of rice cultivation is that plants grow on flooded soils. Such a temporary condition of the landscape can become an unexpected tourist destination. From the methodological point of view, the research combines the potential of time series of satellite high-resolution imagery, for computing vegetation indexes (i.e. NDVI, NDWI etc.), and ground observations, through GIS mapping tools. This interpretation tools are useful to trace a network of slow scenic routes that allow perceiving such temporary landscape conditions and that support a territorial strategy aiming at a sustainable development of these fragile territories.


2020 ◽  
Vol 105 ◽  
pp. 103550
Author(s):  
John Harold Castaño ◽  
Jaime Andrés Carranza-Quiceno ◽  
y. Jairo Pérez-Torres

2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Flávio Eduardo Vilas Boas Júnior ◽  
Amanda Da Silva Ferreira ◽  
Marcos Magalhães De Souza

The fragmentation process that has altered natural environments has been widely discussed, as it causes changes in communities and compromises different environmental functions. In this sense, this study was based on the evaluation of fragmentation on araneofauna of semideciduous seasonal forest fragments, phytophysiognomy belonging to the Atlantic Forest. The study was conducted in three fragments in the municipality of Inconfidentes, southern Minas Gerais, from April 2014 to March 2015. The results showed that there is a similarity in the composition of spider species among the sampled fragments and that the size of the fragment is positively correlated with species richness. Our data show that smaller fragments must be preserved and that agricultural areas maintain the integrity of adjacent forest areas to benefit from the predation dynamics that spiders exert on pests that affect plantations.


FLORESTA ◽  
2015 ◽  
Vol 45 (3) ◽  
pp. 497
Author(s):  
Silvana Manfredi ◽  
Juliano Pereira Gomes ◽  
Paula Iaschitzki Ferreira ◽  
Roseli Lopes da Costa Bortoluzzi ◽  
Adelar Mantovani

A busca do conhecimento sobre a expansão das florestas em relação aos ecossistemas associados (campestre e banhado) aborda a presença de fatores ambientais como o fogo e o pastejo, frequentemente descritos como determinantes dos processos ecológicos favoráveis à dinâmica sucessional. Dessa forma, objetivou-se verificar se existem diferenças na composição florística do interior de fragmentos florestais e entre setores de transição floresta-campo e floresta-banhado, bem como identificar espécies indicadoras para cada um desses ambientes. O estudo foi realizado em fragmentos florestais situados nos municípios de Bom Jardim da Serra e Lages (Coxilha Rica), onde foram instaladas duas parcelas permanentes de 50x50 m, subdivididas em setores de 10x10 m, categorizados em três setores: Floresta Ombrófila Mista, transição floresta x campo e transição floresta x banhado. Há dissimilaridade florística entre os fragmentos florestais dos locais e, também, entre os setores de transição (ecótonos). As espécies indicadoras dos ecótonos estão vinculadas ao estágio inicial da sucessão florestal, apresentando potencial para colonização do campo, podendo atuar no início do processo de expansão da fronteira florestal.AbstractFloristic dissimilarity and indicator species of Araucaria Forest and ecotones. The search for knowledge about the expansion of forests in relation to associated ecosystems (native grassland and wetland) addresses the presence of environmental factors such as fire and grazing, often described as determinants of ecological processes in favor of succession dynamics. The objective here was to verify if there are differences among the floristic composition of the interior of forest fragments and transition sectors of forest-native grassland and forest-wetland, as well as to identify indicator species for each of these environments. The research was conducted in forest fragments located in the municipalities of Bom Jardim da Serra and Lages (Coxilha Rica), SC, where we installed two permanent plots of 50x50 m, subdivided into sectors of 10x10 m categorized into three sectors: Araucaria Forest, forest transition x native grassland and forest x wetland transition. There is floristic dissimilarity between the local forest fragments and also between the transition areas (ecotones). The indicator species of ecotones are linked to early stages of forest succession, with potential for colonization of the field, they can operate in the start of the expansion of the forest boundary process.Keywords: Araucaria Forest; native grassland; wetland; succession.


Land ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 84 ◽  
Author(s):  
Suresh Chaudhary ◽  
Yukuan Wang ◽  
Amod Mani Dixit ◽  
Narendra Raj Khanal ◽  
Pei Xu ◽  
...  

Farmland abandonment is considered as an important phenomenon for changing eco-environmental and sociocultural landscapes of mountainous rural landscape. Many studies have analyzed farmland abandonment, its driving factors, geophysical processes and consequences at landscape: however, very few have focused on mountainous developing countries such as in Nepal, which is a rapidly urbanizing country suffering from serious farmland abandonment. Therefore, our study was an attempt to (i) assess the spatiotemporal extent of farmland abandonment in Nepal, (ii) explore driving factors of farmland abandonment, and (iii) discuss on the eco-environmental and sociocultural consequences in Nepal. We reviewed various literature, documents, and national reports to obtain a dataset pertaining to the overall status of farmland use and changes along with political and socioeconomic changes, economic development processes, and policy and governance in Nepal. Our results showed that farmland abandonment is widespread; however, it is more prevalent in the hilly and mountainous regions of Nepal. A total of 9,706,000 ha, accounting for 23.9% of the total cultivated farmland in Nepal, was abandoned during the period of 2001 to 2010. The driving factors included population growth, scattered distribution of settlements, urbanization, socio-economic development, poor access to physical services, and poor implementation of agriculture development policies. Furthermore, the increasing extent of natural disasters, malaria eradication, land reform and resettlement programs, the complex system of land ownership, land fragmentation, political instabilities, and the intensification of trading in agricultural products also acted as drivers of farmland abandonment in Nepal. Farmland abandonment generates negative effects on rural societies eco-environmentally and sociologically. Abandoned plots were subjected to different forms of geomorphic damage (e.g. landslide, debris flows, gully formation, sinkhole development etc.). Farmland landscape fragmented into a group of smaller interspersed patches. Such patches were opened for grassland. Furthermore, farmland abandonment also has effects on the local population and the whole society in terms of the production of goods (e.g., foods, feed, fiber), as well as services provided by the multi-functionality (e.g. sociocultural practices, values and norms) of the agricultural landscape. Therefore, this study plays an important role in planning and implementing eco-environmental management and social development processes in Nepal.


1999 ◽  
Vol 5 (2) ◽  
pp. 158 ◽  
Author(s):  
Chris Norwood

Increasing demand for resources through a growing world population and the development of consumer led economies has led to large-scale habitat modification. One of the most disturbing aspects of these changes is the loss of biodiversity. Conservation biology as a discipline seeks to counteract or minimize the loss of biodiversity. Management is an Important aspect in achieving this goal. One concept used in Wildlife management and conservation is that of landscape linkages. Linkages are aimed at faclhtatmg .the connectivity for species, communities or ecological processes. There are many types of linkages in the landscape; both natural and human induced. Covered in this book are linkages such as greenways, dispersal corridors, riparian remnants, wildlife corridors, stepping stones, hedgerows and road underpasses. Linkages range in scale from small patches of old-growth forest in a forest mosaic to migratory routes for birds across and between continents.


2013 ◽  
Vol 29 (4) ◽  
pp. 313-319 ◽  
Author(s):  
Jamille de Assis Bomfim ◽  
Roberta Mariano Silva ◽  
Virgínia de Fernandes Souza ◽  
Edyla Ribeiro de Andrade ◽  
Eliana Cazetta

Abstract:To investigate the influence of forests and agroforestry systems on fruit consumption by birds, we studied two landscapes, one covered predominantly with forests and the other dominated by traditional shade cocoa plantations. In each landscape, we sampled three forest fragments and three shade cocoa plantations. We placed 15 artificial fruits in 25, 1–2-m-tall shrubs spaced every 50 m and evaluated the detection and consumption of fruits after 72 h. We used hemispherical photographs positioned above each fruit station to evaluate canopy openness. We found a statistically significant difference in fruit consumption between landscapes, which means that more fruits were detected and consumed in the forest-dominated landscape. However, forests and shade cocoa plantations within each landscape exhibited similar fruit consumption. Canopy openness was similar between the landscapes, however, the cocoa plantations exhibited greater canopy openness than forests. The results of this study reinforce the importance of the presence of forests in the agricultural landscape. Thus, to evaluate the capacity of agroforest to protect species and maintain ecological interactions it is also necessary to consider the landscape context.


2001 ◽  
Vol 12 (5) ◽  
pp. 635-642 ◽  
Author(s):  
Hans Jacquemyn ◽  
Jan Butaye ◽  
Myriam Dumortier ◽  
Martin Hermy ◽  
Noël Lust

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