Using the Lonsdorf model for estimating habitat loss and fragmentation effects on pollination service

AbstractOne of the most important issues related to landscape ecology and ecosystem services is finding the pattern of habitat patches that offers the highest pollination in agricultural landscapes. In this regard, two processes of habitat loss and fragmentation strongly affect the relationship between pollination and the pattern of habitat patches. In the present study, we aimed to examine the effects of habitat loss and fragmentation on pollination separately. For this purpose, first, we generated different simulated agricultural landscapes, including two habitats of forest and agriculture. Then, according to the Lonsdorf model, we estimated the potential of the simulated landscapes in providing pollination in different scenarios. Finally, using statistical models, we estimated the effects of habitat loss and fragmentation on pollination at the landscape and farm levels. Our results showed that the effects of habitat loss and fragmentation on pollination were completely different at the landscape and farm levels. At the landscape level, fragmentation negatively affected pollination, but at the farm level, the maximum pollination rate was observed in the landscapes with a high degree of fragmentation. Regarding the habitat loss effects, our results showed that pollination decreased linearly at the landscape level as habitat amount decreased, but at the farm level, it decreased exponentially. The present study considered the level of analysis (i.e., landscape and farm levels) as a critical factor affecting pollination changes caused by fragmentation. We showed that using the Lonsdorf model could lead to confusing results for the landscape ecologists and alert farmers who want to reduce the adverse effects of fragmentation on their products by creating new forest patches. Therefore, agriculturalists and landscape ecologists should consider that the pollination rate at the landscape and farm levels is completely different according to the model and provide contradictory results about the process of habitat loss effects on pollination.

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Urbanization and Population Genetic Structure of the Panama City crayfish (Procambarus econfinae)

Journal of Heredity ◽

10.1093/jhered/esz072 ◽

2019 ◽

Vol 111 (2) ◽

pp. 204-215

Author(s):

Sarah I Duncan ◽

Ellen P Robertson ◽

Robert J Fletcher ◽

James D Austin

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Habitat Loss ◽

Legal Protection ◽

Habitat Modification ◽

Panama City ◽

Habitat Patches ◽

Anthropogenic Habitat ◽

Habitat Loss And Fragmentation

Abstract For species with geographically restricted distributions, the impacts of habitat loss and fragmentation on long-term persistence may be particularly pronounced. We examined the genetic structure of Panama City crayfish (PCC), Procambarus econfinae, whose historical distribution is limited to an area approximately 145 km2, largely within the limits of Panama City and eastern Bay County, FL. Currently, PCC occupy approximately 28% of its historical range, with suitable habitat composed of fragmented patches in the highly urbanized western portion of the range and managed plantations in the more contiguous eastern portion of the range. We used 1640 anonymous single-nucleotide polymorphisms to evaluate the effects of anthropogenic habitat modification on the genetic diversity and population structure of 161 PCC sampled from across its known distribution. First, we examined urban habitat patches in the west compared with less-developed habitat patches in the east. Second, we used approximate Bayesian computation to model inferences on the demographic history of eastern and western populations. We found anthropogenic habitat modifications explain the genetic structure of PCC range-wide. Clustering analyses revealed significant genetic structure between and within eastern and western regions. Estimates of divergence between east and west were consistent with urban growth in the mid-20th century. PCC have low genetic diversity and high levels of inbreeding and relatedness, indicating populations are small and isolated. Our results suggest that PCC have been strongly affected by habitat loss and fragmentation and management strategies, including legal protection, translocations, or reintroductions, may be necessary to ensure long-term persistence.

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Estimating landscape structure effects on pollination for management of agricultural landscapes

10.21203/rs.3.rs-293659/v1 ◽

2021 ◽

Author(s):

Ehsan Rahimi ◽

Shahindokht Barghjelveh ◽

Pinliang Dong

Keyword(s):

Landscape Composition ◽

Agricultural Landscapes ◽

Edge Density ◽

Forest Patches ◽

Habitat Amount ◽

High Degree ◽

Very High ◽

Landscape Composition And Configuration ◽

Degree Of Fragmentation ◽

Significant Factors

Abstract The present study aims to examine the effects of habitat fragmentation to find a pattern of forest patches in agricultural landscapes that provide the highest pollination level. For this purpose, using simulated agricultural landscapes, including different forest proportions and degrees of fragmentation, pollination in different scenarios was estimated. We used landscape metrics to measure the landscape composition and configuration of each simulated landscape and estimated their statistical relationship with pollination. Our results showed that the effects of fragmentation on pollination were affected by two significant factors; 1- habitat amount and 2- small patches' capacity to supply pollination. Our results showed that when small patches' capacity in supplying pollination was low, fragmentation decreased pollination. When this capacity was very high, landscapes with a high degree of fragmentation showed higher levels of pollination. There was an exception for habitat amounts less than 0.1 of the entire landscape that increasing edge density, aggregation, and the number of patches, resulted in increasing pollination in all scenarios.

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Habitat loss and fragmentation under urbanization : the spatio-temporal dynamics of causes, processes and consequences at landscape level

10.5353/th_b5066230 ◽

2013 ◽

Author(s):

Yujing Xie

Keyword(s):

Habitat Loss ◽

Temporal Dynamics ◽

Habitat Loss And Fragmentation ◽

Spatio Temporal ◽

Landscape Level

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Response of large galliforms and tinamous (Cracidae, Phasianidae, Tinamidae) to habitat loss and fragmentation in northern Guatemala

Oryx ◽

10.1017/s0030605311001451 ◽

2012 ◽

Vol 46 (4) ◽

pp. 567-576 ◽

Cited By ~ 21

Author(s):

Daniel H. Thornton ◽

Lyn C. Branch ◽

Melvin E. Sunquist

Keyword(s):

Habitat Loss ◽

Bird Species ◽

Distribution Patterns ◽

Camera Traps ◽

Forest Patches ◽

Fragmented Landscapes ◽

Game Birds ◽

Habitat Loss And Fragmentation ◽

Surrounding Landscape ◽

The Impact

AbstractThe potential conservation value of fragmented or countryside landscapes in the tropics is being increasingly recognized. However, the degree to which fragmented landscapes can support species and the key patch and landscape features that promote population persistence remain poorly understood for elusive species such as ground-dwelling birds. We examined the presence/absence of seven species of galliforms and tinamous in 50 forest patches of 2.9–445 ha in northern Guatemala using camera traps and audiovisual surveying. After accounting for differences in detectability among species we found great variation in patterns of vulnerability of these species to habitat loss and fragmentation, with the three largest species being the most vulnerable. Distribution patterns of species among patches was influenced more strongly by measures of landscape context, such as the amount and configuration of habitat in the surrounding landscape, than within-patch variation in vegetation structure or disturbance. Our results indicate that large-bodied game birds may be particularly sensitive to habitat loss and fragmentation and emphasize that management efforts for these species need to go beyond consideration of local, within-patch factors to consider the impact of processes in the surrounding landscape. Our findings also demonstrate the utility of camera traps as a methodology for surveying large terrestrial bird species in fragmented landscapes.

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Sensitivity to habitat fragmentation across European landscapes in three temperate forest herbs

Landscape Ecology ◽

10.1007/s10980-021-01292-w ◽

2021 ◽

Author(s):

Tobias Naaf ◽

Jannis Till Feigs ◽

Siyu Huang ◽

Jörg Brunet ◽

Sara A. O. Cousins ◽

...

Keyword(s):

Genetic Differentiation ◽

Habitat Loss ◽

Population Genetic ◽

Life Histories ◽

Temperate Forest ◽

Agricultural Landscapes ◽

Forest Fragments ◽

Forest Herbs ◽

Habitat Loss And Fragmentation ◽

Spatial Isolation

Abstract Context Evidence for effects of habitat loss and fragmentation on the viability of temperate forest herb populations in agricultural landscapes is so far based on population genetic studies of single species in single landscapes. However, forest herbs differ in their life histories, and landscapes have different environments, structures and histories, making generalizations difficult. Objectives We compare the response of three slow-colonizing forest herbs to habitat loss and fragmentation and set this in relation to differences in life-history traits, in particular their mating system and associated pollinators. Methods We analysed the herbs’ landscape-scale population genetic structure based on microsatellite markers from replicate forest fragments across seven European agricultural landscapes. Results All species responded to reductions in population size with a decrease in allelic richness and an increase in genetic differentiation among populations. Genetic differentiation also increased with enhanced spatial isolation. In addition, each species showed unique responses. Heterozygosity in the self-compatible Oxalis acetosella was reduced in smaller populations. The genetic diversity of Anemone nemorosa, whose main pollinators are less mobile, decreased with increasing spatial isolation, but not that of the bumblebee-pollinated Polygonatum multiflorum. Conclusions Our study indicates that habitat loss and fragmentation compromise the long-term viability of slow-colonizing forest herbs despite their ability to persist for many decades by clonal propagation. The distinct responses of the three species studied within the same landscapes confirm the need of multi-species approaches. The mobility of associated pollinators should be considered an important determinant of forest herbs’ sensitivity to habitat loss and fragmentation.

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PollMap: a software for crop pollination mapping in agricultural landscapes

Journal of Ecology and Environment ◽

10.1186/s41610-021-00210-0 ◽

2021 ◽

Vol 45 (1) ◽

Author(s):

Ehsan Rahimi ◽

Shahindokht Barghjelveh ◽

Pinliang Dong ◽

Maghsoud Arshadi Pirlar ◽

Mohammad Mehdi Jahanbakhshian

Keyword(s):

Landscape Planning ◽

Agricultural Landscapes ◽

Floral Resources ◽

Crop Pollination ◽

Wild Bees ◽

Forest Patches ◽

Pollination Service ◽

Flight Range ◽

Service Mapping ◽

Lonsdorf Model

Abstract Background Ecosystem service mapping is an important tool for decision-making in landscape planning and natural resource management. Today, pollination service mapping is based on the Lonsdorf model (InVEST software) that determines the availability of nesting and floral resources for each land cover and estimates pollination according to the foraging range of the desired species. However, it is argued that the Lonsdorf model has significant limitations in estimating pollination in a landscape that can affect the results of this model. Results This paper presents a free software, named PollMap, that does not have the limitations of the Lonsdorf model. PollMap estimates the pollination service according to a modified version of the Lonsdorf model and assumes that only cells within the flight range of bees are important in the pollination mapping. This software is produced for estimating and mapping crop pollination in agricultural landscapes. The main assumption of this software is that in the agricultural landscapes, which are dominated by forest and agriculture ecosystems, forest patches serve only as a nesting habitat for wild bees and the surrounding fields provide floral resources. Conclusion The present study provided new software for mapping crop pollination in agricultural landscapes that does not have the limitations of the Lonsdorf model. We showed that the use of the Lonsdorf model for pollination mapping requires attention to the limitations of this model, and by removing these limitations, we will need new software to obtain a reliable mapping of pollination in agricultural landscapes.

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