23 research outputs found
Super-regional land-use change and effects on the grassland specialist flora
Habitat loss through land-use change is the most pressing threat to biodiversity worldwide. European semi-natural grasslands have suffered an ongoing decline since the early twentieth century, but we have limited knowledge of how grassland loss has affected biodiversity across large spatial scales. We quantify land-use change over 50-70 years across a 175,000 km(2) super-region in southern Sweden, identifying a widespread loss of open cover and a homogenisation of landscape structure, although these patterns vary considerably depending on the historical composition of the landscape. Analysing species inventories from 46,796 semi-natural grasslands, our results indicate that habitat loss and degradation have resulted in a decline in grassland specialist plant species. Local factors are the best predictors of specialist richness, but the historical landscape predicts present-day richness better than the contemporary landscape. This supports the widespread existence of time-lagged biodiversity responses, indicating that further species losses could occur in the future
HistMapR: rapid digitization of historical land-use maps in R
1. Habitat destruction and degradation represent serious threats to biodiversity, and quantification of land-use change over time is important for understanding the consequences of these changes to organisms and ecosystem service provision.
2. Comparing land use between maps from different time periods allows estimation of the magnitude of habitat change in an area. However, digitizing historical maps manually is time-consuming and analyses of change are usually carried out at small spatial extents or at low resolutions.
3. HistMapR contains a number of functions that can be used to semi-automatically digitize historical land use according to a map's colours, as defined by the RGB bands of the raster image. We test the method on different historical land-use map series and compare results to manual digitizations.
4. Digitization is fast, and agreement with manually digitized maps of around 80–90% meets common targets for image classification. We hope that the ability to quickly classify large areas of historical land use will promote the inclusion of land-use change into analyses of biodiversity, species distributions and ecosystem services
GrassPlot v. 2.00 – first update on the database of multi-scale plant diversity in Palaearctic grasslands
Abstract: GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). Following a previous Long Database Report (Dengler et al. 2018, Phyto- coenologia 48, 331–347), we provide here the first update on content and functionality of GrassPlot. The current version (GrassPlot v. 2.00) contains a total of 190,673 plots of different grain sizes across 28,171 independent plots, with 4,654 nested-plot series including at least four grain sizes. The database has improved its content as well as its functionality, including addition and harmonization of header data (land use, information on nestedness, structure and ecology) and preparation of species composition data. Currently, GrassPlot data are intensively used for broad-scale analyses of different aspects of alpha and beta diversity in grassland ecosystems
Långsiktig vegetationsutveckling i anlagda permanenta åkerkanter
Biodiversity loss, pesticide drift and nutrient leakage are some of the negative effects caused by intensified agriculture. One measure to reduce these negative effects is to establish permanent field margins. Between 1988 and 1990 experiments with broadened permanent field margins were established at three sites near Flen and Uppsala in south of Sweden. One of the aims was to study how different treatments affected the margin vegetation and if the abundance of weeds could be suppressed. The treatments consisted of establishing new or broadening pre-existent field margins, sowing different seed-mixtures (e.g. “meadow plants”) and manage them by yearly mowing with removal of cut material. The vegetation was investigated at three occasions after establishment during a 20-year period. At the second and third occasion, adjacent untreated field margins were examined for comparisons.
The results showed that sowing different species, particularly “meadow plants”, can substantially change the field margin flora in a long-term perspective and lower the abundance of weeds, compared to untreated margins. Out of the sown 32 “meadow plants” species, 22 remained after more than 20 years. Several of the sown species that normally occur in well-managed meadows and pastures were able to survive in the experiments.Dagens intensifierade och maskinanpassade jordbruk med stora åkrar, monokultur, användande av kemiska bekämpningsmedel och konstgödsel, och ett skifte från höpro-duktion till ensilage, har påverkat såväl biodiversitet som hela landskapsbilden. Ett av landskapselementen som ofta har rationaliserats bort är åkerkanten, dels eftersom det är en ekonomisk och praktisk fördel för lantbrukaren att ha sammanhängande åkrar, men även på grund av att åkerkanten har ansetts vara en ogräs- och skadedjursspridare. Det senare har motbevisats av flera undersökningar där permanenta åkerkanter har anlagts (Fritch et al., 2011; Marshall, 2009; Musters et al., 2009; Moonen & Marshall, 2001; Smith et al., 1999; Kleijn et al., 1998). Åkerkanter har visats sig vara viktiga habitat för många växter och djur, däribland insekter, fåglar och däggdjur, och kan också bidra till många ekosystemtjänster, såsom pollinering och biologisk bekämpning av skadedjur, men även förhindrande av erosion och spridning av jordbrukskemilkalier. På senare tid har dessa positiva egenskaper lyfts fram och man har infört olika ersättningssystem med ekonomisk kompensation för lantbrukarna.
I Europa har flera fältförsök startats upp för att studera effekter av olika sorters åker-kanter. Under 1988-1990 inleddes fältförsök med breddade, permanenta åkerkanter på tre lokaler utanför Flen och Uppsala. Ett av syftena var att studera hur olika behandlingar påverkade åkerkantsvegetationen och huruvida åtgärderna hade någon effekt på abundansen av ogräs. Behandlingarna bestod av etablering av helt nya eller breddning av existerande åkerkanter, samt sådd av olika fröblandningar (bl.a. "ängsväxter"). Åkerkanterna har sedan dess skötts genom årlig slåtter och bortförsel av slaget växtmaterial. Vegetationen inventerades vid tre tillfällen under en 20-årsperiod och närliggande obehandlade åkerkanter inventerades vid de två senaste tillfällena för att göra jämförelser.
Resultaten i denna studie visar att man genom sådd av olika arter, i synnerhet ”ängs-växter”, väsentligt kan förändra åkerkantsfloran långsiktigt och även minska abundansen av ogräs jämfört med obehandlade åkerkanter. Över 20 år efter försökens start återfanns 22 av de sådda 32 ”ängsväxterna” i åkerkanterna, varav flera av dessa arter vanligtvis påträffas i välskötta ängs- och betesmarker.
Nyckelord: Åkerkant, Långtidsstudie, Vegetationsutveckling, Biodiversitet, Ängsväxter, Ogräs, Jordbru
Restoration of semi-natural grasslands : Impacts on biodiversity, ecosystem services and stakeholder perceptions
Humans play a major role shaping the living conditions for not only ourselves, but also all other species on Earth. In fact, some species-rich habitat types require human management to uphold the biodiversity and related ecosystem services. One of the world’s most biodiverse habitats on small spatial scales, semi-natural grasslands, have been formed over the course of centuries through extensive grazing and mowing. However, due to political and economic reasons, up to 90% of the European semi-natural grasslands have been lost during the 20th century. To counteract these drastic losses, restoration actions are implemented in environmental policies across Europe. Yet, knowledge of the long-term restoration effects on biodiversity and ecosystem services is still limited. The vast need for future restoration also requires a better understanding of how different pre-conditions affect the restoration outcome, as well as how stakeholders perceive restoration, to be able to prioritise between sites and recognise the limitations of the restoration process. In this thesis, I examine restoration outcomes in Swedish semi-natural grasslands, in terms of plant diversity, associated ecosystem services and from the farmers’ and land-owners’ perspective. The outcome is also analysed in relation to environmental factors at the local and landscape scale. I found that the overall community composition recovered to resemble intact reference communities, but it took relatively long time (12-20 years). Moreover, the reference sites still had higher species richness both at large and small spatial scales, more grassland specialist species and a higher abundance of plant species important to the five tested ecosystem services (meat production, pollination, water retention, temperature regulation and cultural heritage). My results show that prioritising large, unfertilised, newly abandoned grasslands situated in landscapes containing a large grassland specialist species pool and high amounts of intact and remnant semi-natural grasslands, could speed up the plant recovery. However, prioritising fast results does not necessarily ensure long-term success at a larger spatial scale. Since restoration success can be interpreted differently depending on evaluation measure used, pre-defined, clear and realistic goals are essential. While the surveyed farmers and landowners overall perceived the restoration as successful, 40% were unsure whether the grasslands will be managed in the future. Low profitability still poses a threat to their maintenance and thus, also to the coupled biodiversity and ecosystem services. Policy changes are therefore urgently needed to facilitate incentives for sustained management of restored and intact European semi-natural grasslands in a long-term perspective.Människan har sedan länge påverkat jordens ekosystem, där vissa habitat numer är beroende av skötsel för att upprätthålla biologisk mångfald och ekosystemtjänster. I naturbetesmarker och ängar (traditionella gräsmarker) har århundranden av hävd genom bete och slåtter format en artrikedom att jämföra med tropisk regnskog, med skillnaden att många av dessa arter är beroende av hävden för sin överlevnad. På grund av det senaste århundrandets jordbruksintensifiering har dock upp till 90% av de europeiska gräsmarkerna vuxit igen eller omvandlats till åkermark eller skogsplantering. För att motverka detta är restaurering av dessa habitat en viktig åtgärd som ingår i bl.a. EU:s ekonomiska stödsystem till lantbrukare. Ekonomiska incitament för restaurering har funnits i flera decennier, men kunskapen om långsiktiga effekter på biologisk mångfald och ekosystemtjänster är fortfarande relativt begränsad. För att möta det omfattande framtida restaureringsbehovet behövs också mer information om hur olika miljöfaktorer kan påverka resultatet, samt hur berörda aktörer uppfattar restaureringen. I denna avhandling undersöker jag restaurering av svenska traditionellt hävdade gräsmarker, med fokus på mångfald av växter och ekosystemtjänster, samt ur lantbrukares och markägares perspektiv. Detta analyseras i förhållande till lokala förhållanden i gräsmarkerna och omgivande landskapsfaktorer. Jag fann att artsammansättningen i restaurerade gräsmarker utvecklades till att likna sammansättningen i kontinuerligt hävdade (intakta) referensgräsmarker, men att denna återhämtning tog relativt lång tid (12-20 år). Referensmarkerna hade dock fortfarande högre artrikedom, fler gräsmarksspecialiserade arter och högre abundans av växter viktiga för fem ekosystemtjänster: köttproduktion, pollinering, vattenhållningsförmåga, kolinlagring och kulturarv. Mina resultat visade även att prioritering av stora, ogödslade, nyligen övergivna gräsmarker belägna i landskap med många intakta gräsmarker och resthabitat, samt en stor artpool med gräsmarksspecialister, skulle kunna påskynda växters återetablering. Det bör dock påpekas att restaurering av gräsmarker kan ge goda effekter också i andra slags landskap, även om det kan ta längre tid. Sammantaget synliggör min avhandling att beroende på vilken utvärderingsmetod som används kan restaureringsresultatet tolkas på olika sätt. För att kunna göra en korrekt utvärdering behövs därför tydliga och realistiska mål som definierats innan restaureringen. Lantbrukarna och markägarna upplevde överlag att restaureringen varit framgångsrik. Trots detta var 40% osäkra på huruvida dessa gräsmarker kommer att skötas i framtiden, framför allt på grund av låg lönsamhet. Därmed är det av yttersta vikt att stödsystemen utformas för att gynna hållbar och långsiktig hävd av både restaurerade och intakta naturbetesmarker och ängar i Europa.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p
Long Term Positive Effect of Grassland Restoration on Plant Diversity - Success or Not?
<div><p>Restoration is important for biodiversity conservation worldwide, but surprisingly little is known about its efficiency in a long-term perspective. In this study, we re-examined Swedish semi-natural grasslands 12–20 years after the restoration, by comparing field inventories of vascular plant species diversity made in 2001 with follow-up inventories in 2012. We also analysed restoration effect in relation to six environmental factors and used continuously managed semi-natural grasslands as references of desired state after restoration. We found that total species richness increased over time but not to reference levels, while there were no significant changes in species density or number of grassland specialists. However, the overall species composition in the restored sites, as well as grassland specialist composition, now largely resembled reference conditions. Fertilisation and time between abandonment and restoration were the only environmental variables that affected total species composition change, while site area affected change in grassland specialist composition. Our results show that restoration of semi-natural grasslands can contribute to conservation of semi-natural habitats and their associated biodiversity. Yet, due to the vague restoration goals for these sites, it is difficult to evaluate the restoration success, which emphasise the general need for clear and measurable goals.</p></div
Site descriptions of 16 restored permanent semi-natural grasslands (A-P) in Sweden.
<p>Site descriptions of 16 restored permanent semi-natural grasslands (A-P) in Sweden.</p
The future of semi-natural pastures in Sweden. Report (English version), Symposium and workshop in Jönköping March 8-9th 2017
This report summarises the symposium and workshop regarding the future of semi-natural pastures in Sweden, held in Jönköping March 8-9th 2017. <br><br>The first day consisted of a symposium where presentations and subsequent discussions were based on three main topics:<br>- What are the <i>motives </i>for continued management of semi-natural pastures?<br>- What are the <i>attitudes </i>of different actors to these motives in relation to agricultural benefits?<br>- What are the <i>actions </i>needed to ensure sustainable future use of semi-natural pastures?<br><br>On the second day, three parallel workshops were held allowing for the topics from day one to be discussed more thoroughly. The workshop sessions were divided into three themes:<br>1. <i>The Design of Future Subsidy Systems</i><br>2. <i>Future and Alternative Management Methods</i><br>3. <i>Information and Communication</i><br><br>The purpose of this report is to compile all the thoughts, ideas and suggestions that emerged from the workshop, regarding potential measures that could be implemented to ensure the future sustainable management of semi-natural pastures in Sweden. The report first summarises the presentations from the first day of the meeting to provide context to the feedback received from participating stakeholders. <br><br>For more information (in Swedish):<br><u>https://sites.google.com/view/naturbete2017</u><br><br>This report is also published in Swedish, link below (DOI: 10.6084/m9.figshare.5097172).<br><br><br><br
Species composition shift in restored semi-natural grasslands.
<p>Detrended correspondence analysis (DCA) of the total species composition in the restored sites at Time 1 (T1, i.e. 2001) and Time 2 (T2, i.e. 2012), and at the continuously managed reference sites at Time 2.</p
Local variables responsible for the specialist species composition in the restored semi-natural grasslands.
<p>Constrained partial canonical correspondence analysis (inventory time set as a co-variable (Time 1 = year 2001, Time 2 = year 2012)). The variable ‘Area (log)’ (explained 5.1%) was significant.</p