Browsing by Subject "Landscape"

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  • Guan, Yanlong; Lu, Hongwei; Jiang, Yelin; Tian, Peipei; Qiu, Lihua; Heiskanen, Janne; Pellikka, Petri (2021)
    Variations in climate types are commonly used to describe changes in natural vegetation cover in response to global climate change. However, few attempts have been made to quantify the heterogeneous dynamics of climate types. In this study, based on the Coupled Model Intercomparison Project phase 5 (CMIP5) historical and representative concentration pathway (RCP) runs from 18 global climate models, we used Shannon's Diversity Index (SHDI) and Simpson's Diversity Index (SIDI) to characterise of global climate heterogeneity from a morphological perspective. Our results show that global climate heterogeneity calculated by the SHDI/SIDI indices decreased from 1901 to 2095 at a significance level of 0.01. As radiative forcing intensified from RCP 2.6 to 8.5, the SHDI/SIDI decreased significantly. Furthermore, we observed that the spatial distribution of global climate heterogeneity was significantly reduced, with a pronounced latitudinal trend. Sensitivity analysis indicated that the temperature increase played a more significant role in reducing global climate heterogeneity than precipitation under the three warming scenarios, which is possibly attributed to anthropogenic forcing. Our findings suggest that the dynamics of global climate heterogeneity can be an effective means of quantifying global biodiversity loss.
  • Susi, Hanna; Filloux, Denis; Frilander, Mildco J.; Roumagnac, Philippe; Laine, Anna-Liisa (2019)
    Wild plant populations may harbour a myriad of unknown viruses. As the majority of research efforts have targeted economically important plant species, the diversity and prevalence of viruses in the wild has remained largely unknown. However, the recent shift towards metagenomics-based sequencing methodologies, especially those targeting small RNAs, is finally enabling virus discovery from wild hosts. Understanding this diversity of potentially pathogenic microbes in the wild can offer insights into the components of natural biodiversity that promotes long-term coexistence between hosts and parasites in nature, and help predict when and where risks of disease emergence are highest. Here, we used small RNA deep sequencing to identify viruses in Plantago lanceolata populations, and to understand the variation in their prevalence and distribution across the Aland Islands, South-West Finland. By subsequent design of PCR primers, we screened the five most common viruses from two sets of P. lanceolata plants: 164 plants collected from 12 populations irrespective of symptoms, and 90 plants collected from five populations showing conspicuous viral symptoms. In addition to the previously reported species Plantago lanceolata latent virus (PlLV), we found four potentially novel virus species belonging to Caulimovirus, Betapartitivirus, Enamovirus, and Closterovirus genera. Our results show that virus prevalence and diversity varied among the sampled host populations. In six of the virus infected populations only a single virus species was detected, while five of the populations supported between two to five of the studied virus species. In 20% of the infected plants, viruses occurred as coinfections. When the relationship between conspicuous viral symptoms and virus infection was investigated, we found that plants showing symptoms were usually infected (84%), but virus infections were also detected from asymptomatic plants (44%). Jointly, these results reveal a diverse virus community with newly developed tools and protocols that offer exciting opportunities for future studies on the eco-evolutionary dynamics of viruses infecting plants in the wild.
  • Alexandridis, Nikolaos; Marion, Glenn; Chaplin-Kramer, Rebecca; Dainese, Matteo; Ekroos, Johan; Grab, Heather; Jonsson, Mattias; Karp, Daniel S.; Meyer, Carsten; O'Rourke, Megan E.; Pontarp, Mikael; Poveda, Katja; Seppelt, Ralf; Smith, Henrik G.; Martin, Emily A.; Clough, Yann (2021)
    Natural control of invertebrate crop pests has the potential to complement or replace conventional insecticide based practices, but its mainstream application is hampered by predictive unreliability across agroecosystems. Inconsistent responses of natural pest control to changes in landscape characteristics have been attributed to ecological complexity and system-specific conditions. Here, we review agroecological models and their potential to provide predictions of natural pest control across agricultural landscapes. Existing models have used a multitude of techniques to represent specific crop-pest-enemy systems at various spatiotemporal scales, but less wealthy regions of the world are underrepresented. A realistic representation of natural pest control across systems appears to be hindered by a practical trade-off between generality and realism. Nonetheless, observations of context-sensitive, trait-mediated responses of natural pest control to land-use gradients indicate the potential of ecological models that explicitly represent the underlying mechanisms. We conclude that modelling natural pest control across agroecosystems should exploit existing mechanistic techniques towards a framework of contextually bound generalizations. Observed similarities in causal relationships can inform the functional grouping of diverse agroecosystems worldwide and the development of the respective models based on general, but context-sensitive, ecological mechanisms. The combined use of qualitative and quantitative techniques should allow the flexible integration of empirical evidence and ecological theory for robust predictions of natural pest control across a wide range of agroecological contexts and levels of knowledge availability. We highlight challenges and promising directions towards developing such a general modelling framework.
  • Rosendahl, Ulrika (2015)
    The medieval hamlet Mankby in Espoo, Southern Finland, excavated from 2007–2013, has revealed a landscape that reflects the complex development of the region – from the initial Swedish colonization to the emergence of an established medieval village, a village that was abruptly dissolved in 1556, when the freeholding peasants were forced to leave their land to the royal demesne that the Swedish king Gustavus Vasa founded on this spot. This study explores this landscape change, and the different layers in the landscape through analyse of historical maps combined with data from archaeological field work. The land use in the area gives a quite stable impression from the end of the middle ages to the enlightenment, even though a drastic change in the experienced landscape appeared when the demesne took over the land. In contrast, the medieval hamlet period from the 13th to the mid-16th century show shifts in the land use and movements within the toftland that reflects the dynamics of the medieval period and shifts in agricultural technique.
  • Savilaakso, Sini; Häkkilä, Matti; Johansson, Anna; Uusitalo, Anne; Sandgren, Terhi; Mönkkönen, Mikko; Puttonen, Pasi (2019)
    Biodiversity is vital for human well-being, but is threatened by human actions world-wide. In the boreal zone, harvesting and management of forests on an industrial scale is the most important factor driving habitat change and degradation. Over time different forest management regimes have been implemented but their impact on biodiversity at different spatial and temporal scales has not been systematically reviewed although non-systematic reviews on the topic exist. The aim of this article is to describe a protocol for a systematic review to synthesise and compare the impacts of two different forest management systems on biodiversity at different spatial and temporal scales. The topic for the systematic review arose from the discussions with the Finnish forestry sector and was further defined in a stakeholder workshop. Research questions addressed by the systematic review protocol are: (1) What are the stand-level effects of even-aged and uneven-aged forest management on boreal forest biodiversity in Fennoscandia and European Russia? (2) What is the effect of these same forest management systems on biodiversity at landscape level?
  • Savilaakso, Sini; Häkkilä, Matti; Johansson, Anna; Uusitalo, Anne; Sandgren, Terhi; Mönkkönen, Mikko; Puttonen, Pasi (BioMed Central, 2019)
    Abstract Background Biodiversity is vital for human well-being, but is threatened by human actions world-wide. In the boreal zone, harvesting and management of forests on an industrial scale is the most important factor driving habitat change and degradation. Over time different forest management regimes have been implemented but their impact on biodiversity at different spatial and temporal scales has not been systematically reviewed although non-systematic reviews on the topic exist. The aim of this article is to describe a protocol for a systematic review to synthesise and compare the impacts of two different forest management systems on biodiversity at different spatial and temporal scales. The topic for the systematic review arose from the discussions with the Finnish forestry sector and was further defined in a stakeholder workshop. Research questions addressed by the systematic review protocol are: (1) What are the stand-level effects of even-aged and uneven-aged forest management on boreal forest biodiversity in Fennoscandia and European Russia? (2) What is the effect of these same forest management systems on biodiversity at landscape level? Methods Animal, plant, and fungal diversity is addressed. Bibliographic databases and organizational websites will be searched, and internet search engines will be utilized to find relevant literature. The searches will be conducted in English, Finnish, Swedish, and Russian. Articles will be screened regarding the inclusion and exclusion criteria at title, abstract, and full-text stage. The validity of included studies will be evaluated against appraisal criteria and studies categorized based on their risk of bias. A narrative synthesis will be conducted to describe the findings. If enough quantitative data can be retrieved from the studies, a meta-analysis will be conducted.