Influence Of Land-use Intensity Research Articles

Habitat Suitability of European Land Systems for Terrestrial Vertebrates

ABSTRACTMotivationAccurate estimates of species distributions are crucial for biogeography, spatial conservation, and for assessing the impacts of human activities on species. However, existing approaches to estimate species distributions have typically neglected the influence of land use intensity, potentially overlooking the negative impacts of high‐intensity land uses on biodiversity. Here, we build a dataset documenting the habitat suitability of European land systems for terrestrial vertebrate species, based on a novel land system map of Europe that factors in land use intensity. Our database offers refined and up‐to‐date information on terrestrial vertebrate distributions in Europe by explicitly considering land use intensity.Main Types of Variables ContainedWe created a table defining the suitability of land use classes as habitats for each species. We then built Area of Habitat (AOH) maps for each species by filtering out unsuitable habitat from the latest available estimates of species ranges. AOH maps were then compared with occurrence records from the Global Biodiversity Information Facility (GBIF). Processed datasets and R scripts are publicly available online, facilitating the use of our approach to refine expert‐based distributions for other taxa, land system classifications and regions worldwide.Spatial Location and GrainThe AOH maps cover the spatial extent of the European Union (EU) with the United Kingdom, Norway, Switzerland, and the Western Balkans. The AOH maps are at a 1 km2 resolution.Time Period and GrainThe dataset uses information published during the last 10 years.Major Taxa and Level of MeasurementHabitat suitability was documented for 1155 terrestrial vertebrate species known to occur in Europe: 279 mammals, 520 birds, 251 reptiles and 104 amphibians.Software FormatWe provide the habitat suitability table in a comma‐separated values (csv) format. The AOH maps are available as raster files. R scripts are publicly accessible on GitHub.

Looking for Hidden Enemies of Metabarcoding: Species Composition, Habitat and Management Can Strongly Influence DNA Extraction while Examining Grassland Communities.

Despite the raising preoccupation, the critical question of how the plant community is composed belowground still remains unresolved, particularly for the conservation priority types of vegetation. The usefulness of metabarcoding analysis of the belowground parts of the plant community is subjected to a considerable bias, that often impedes detection of all species in a sample due to insufficient DNA quality or quantity. In the presented study we have attempted to find environmental factors that determine the amount and quality of DNA extracted from total plant tissue from above- and belowground samples (1000 and 10,000 cm2). We analyzed the influence of land use intensity, soil properties, species composition, and season on DNA extraction. The most important factors for DNA quality were vegetation type, soil conductometry (EC), and soil pH for the belowground samples. The species that significantly decreased the DNA quality were Calamagrostis epigejos, Coronilla varia, and Holcus lanatus. For the aboveground part of the vegetation, the season, management intensity, and certain species—with the most prominent being Centaurea rhenana and Cirsium canum—have the highest influence. Additionally, we found that sample size, soil granulation, MgO, organic C, K2O, and total soil N content are important for DNA extraction effectiveness. Both low EC and pH reduce significantly the yield and quality of DNA. Identifying the potential inhibitors of DNA isolation and predicting difficulties of sampling the vegetation plots for metabarcoding analysis will help to optimize the universal, low-cost multi-stage DNA extraction procedure in molecular ecology studies.

Biodiversity in cultural landscapes: influence of land use intensity on bird assemblages

Land use changes and intensification have been amongst the major causes of the on-going biodiversity decline in Europe. A better understanding and description of how different levels of land use intensity affect biodiversity can support the planning and evaluation of policy measures. Our study investigates how land use-related landscape characteristics affect bird diversity, considering different spatial scales and species groups with characteristic habitat use. We used breeding bird census data from 2693 observation points along 206 transects and applied a random effects hurdle model to describe the influence of the landscape characteristics altitude, forest proportion, patch density, land cover diversity, and land use intensity on avian species richness. Land use intensity and related landscape characteristics formed an important explanatory variable for bird richness. Increasing land use intensity was accompanied by a decrease in bird species richness. While forest bird richness decreased with a decreasing amount of forest cover, farmland species richness increased. This led to a bird diversity peak in extensively used semi-open landscapes. The influence of land cover diversity on species richness was small. Increasing patch density had positive effects on forest birds, but affected farm birds negatively. The strongest correlation between land use-based indicators and bird diversity was determined using spatial indicators at a close range around observation points (100–500 m radius). Our results assist interpretation of the Pan-European Common Bird Indices and emphasize the importance of using multifaceted and thoroughly selected indicators in the context of biodiversity monitoring and decision-making support.

Influence of Land use Intensity and Weed Management Practice on Field Emergence, Characterization and Growth of Weeds in Southern Guinea Savanna of Nigeria

The effects of land use intensity and weed management practice on weed seedling emergence, growth and characterization of weed species were examined at Ilorin, in the southern Guinea savanna of Nigeria. The study was conducted on three pieces of land with known cropping history, laid out as randomized complete block design with split-plot arrangement and three replicates. The main plots consisted of two cropping systems (sole maize and no cropping in continuously cultivated maize field, sole cowpea and no cropping in continuously cultivated cowpea field and sole maize, sole cowpea and no cropping in natural fallow field) while the sub plots consisted of three weed control methods (chemical weed control, hand hoeing at 3 and 6 weeks after planting and no weed control). Annual broadleaf weeds were most prevalent across the trial fields and constituted above 60 % of the total weed population. Cleome vicosa L., Euphorbia heterophylla L., Passiflora foetida L., Tridax procumbens L., Fimbristylis littoralis Gaudet and Rottboellia cochinchinensis (Lour.)Clayton were prevalent at continuously cultivated fields, Pycereus lanceolatus (poir) C.B.Cl, Phyllantus amarus Schum & Thonn. and Mariscus alternifolus Vahl had high frequency of occurrence at the natural fallow fields while Cyprus tuberosus Rotth was prevalent in all the sampled fields. In all, the frequency of occurrence of weeds was high at the continuously cultivated fields. Land use showed a pattern of increasing weed density in response to increasing land use intensity. These results show that intensive land use increases weed problems on farmers’ fields . The implication of the result on weed management is discussed. Keywords : Land use, weed emergence, sole maize, sole cowpea, follow

Influence of Land Use Intensity on the Diversity of Ammonia Oxidizing Bacteria and Archaea in Soils from Grassland Ecosystems

In the present study, the influence of the land use intensity on the diversity of ammonia oxidizing bacteria (AOB) and archaea (AOA) in soils from different grassland ecosystems has been investigated in spring and summer of the season (April and July). Diversity of AOA and AOB was studied by TRFLP fingerprinting of amoA amplicons. The diversity from AOB was low and dominated by a peak that could be assigned to Nitrosospira. The obtained profiles for AOB were very stable and neither influenced by the land use intensity nor by the time point of sampling. In contrast, the obtained patterns for AOA were more complex although one peak that could be assigned to Nitrosopumilus was dominating all profiles independent from the land use intensity and the sampling time point. Overall, the AOA profiles were much more dynamic than those of AOB and responded clearly to the land use intensity. An influence of the sampling time point was again not visible. Whereas AOB profiles were clearly linked to potential nitrification rates in soil, major TRFs from AOA were negatively correlated to DOC and ammonium availability and not related to potential nitrification rates.

Influence of land-use intensity on the spatial distribution of N-cycling microorganisms in grassland soils

A geostatistical approach using replicated grassland sites (10 m × 10 m) was applied to investigate the influence of grassland management, i.e. unfertilized pastures and fertilized mown meadows representing low and high land-use intensity (LUI), on soil biogeochemical properties and spatial distributions of ammonia-oxidizing and denitrifying microorganisms in soil. Spatial autocorrelations of the different N-cycling communities ranged between 1.4 and 7.6 m for ammonia oxidizers and from 0.3 m for nosZ-type denitrifiers to scales >14 m for nirK-type denitrifiers. The spatial heterogeneity of ammonia oxidizers and nirS-type denitrifiers increased in high LUI, but decreased for biogeochemical properties, suggesting that biotic and/or abiotic factors other than those measured are driving the spatial distribution of these microorganisms at the plot scale. Furthermore, ammonia oxidizers (amoA ammonia-oxidizing archaea and amoA ammonia-oxidizing bacteria) and nitrate reducers (napA and narG) showed spatial coexistence, whereas niche partitioning was found between nirK- and nirS-type denitrifiers. Together, our results indicate that spatial analysis is a useful tool to characterize the distribution of different functional microbial guilds with respect to soil biogeochemical properties and land-use management. In addition, spatial analyses allowed us to identify distinct distribution ranges indicating the coexistence or niche partitioning of N-cycling communities in grassland soil.