Impact of Energy Landscapes on the Abundance of Eurasian Skylark (Alauda arvensis), an Example from North Germany

Abstract

The increasing use of biomass for energy production is reshaping landscapes into energy landscapes. Our study aims to analyze the impact of the biogas energy landscape on the abundance of Eurasian skylark. The biogas power plants have a high impact on the landscape, because of the energy crops like silage maize and rape. We analyze land-use and land-cover heterogeneity in connection with this bird species in the Federal State of Schleswig-Holstein. Three databases are used: abundance data of a typical farmland bird (Eurasian skylark), Corine land cover, and statistical land-use data from the German Agricultural Structure Survey. Several spatial analyses and statistical analyses were conducted. Generalized linear models are used with model averaging and predicted marginal effects were calculated. We estimate the changes in individuals per km2 by considering six crop types and the Shannon Diversity Index (SDI). The Eurasian skylark abundance has a significant negative correlation with the area of the inland wetlands, the Shannon Diversity Index (SDI), permanent crops, silage maize, and rape. We found significant positive correlation with the pasture, potato, and wheat. The replacement of pastures, Eurasian skylarks’ preferred habitat, with energy crops, mostly silage maize, and the ongoing homogenization of the landscape, negatively affected this species’ distribution in the study area.

Modelling the Impacts of Habitat Changes on the Population Density of Eurasian Skylark (Alauda arvensis) Based on Its Landscape Preferences

“…The skylark is a typical farmland bird; therefore, it is not a surprise that wetland areas, water bodies, and water courses are not suitable habitat types for this species. The main reason of the negative significant relation of the forest is the lack of openness, which is very important for the skylark [10,11,16,55]. In our research we were not take difference between the type of forests, because according to previous studies every types of forest areas are not habitats of this species.…”

“…The closed-grasslands LULC category showed the highest significant relation, thereby having the most important effect on skylark abundance. The arable-land LULC category is also a preferred category according to the literature [11,18,29,50]. The nonpreferred group (class) of LULC categories contains land-cover types with significant negative relations with skylark abundance: built-up land, green urban areas, complex cultivation patterns, forests, and wetlands and water surfaces.…”

“…The complex cultivation pattern land-cover type has negative significant relation with skylark data. Other authors underlines that the skylarks do not prefer heterogeneous agricultural lands because this rural landscape contains many different LULC patches, including also those that are not preferable to the skylark, like vineyards, fruit and berry plantations (because of its height, they obscure the view) [10,11,16,17]. Small parcels of, annual crops, city gardens pastures, fallow lands and/or permanent crops somewhere with scattered houses.…”

“…Very few studies have investigated the dramatic decline of the abundance of farmland birds, and its connection with change in landscape structure and land-cover heterogeneity [7][8][9]. There are some regional (country)-scale studies that analyze the connection between land-cover types and farmlandbird population data [10][11][12][13][14][15]. These studies have indicated that the abundance of farmland birds is significantly connected with the intensity of agricultural cultivation, crop heterogeneity, and land-use change.…”

“…According to the pattern and process paradigm, which analyze the relationship between the landscape patterns spatial distribution and landscape processes, landscape indices are widely used as indicators of biodiversity and habitat changes [13,[25][26][27][28]. After we identified preferred and non-preferred habitats for skylarks, we could calculate shape-and sizerelated class-level landscape metrics, and land-cover heterogeneity, and estimate the collective impact of these variables on skylark abundance [9][10][11]13,29,30].…”