Luonnonhoitopellot luonnon monimuotoisuuden edistämisessä : luonnonhoitopeltotyypin ja maiseman vaikutukset

Environmental fallows are fields that aim to produce environmental benefits instead of agricultural products. In many European countries, the establishment and management of fallows is funded via agri-environmental programmes. This thesis focuses on the biodiversity benefits of environmental fallows in boreal farmland. I examined the impacts of different fallow types and landscape structure on the diversity and species composition of multiple taxa in fallows. I also aimed to evaluate what fallow types, and in what landscape context, are needed to contribute to different biodiversity objectives: the promotion of conservation concern species, overall species diversity or ecosystem services. Species richness and composition of the studied species groups differed substantially between fallow types, and landscape context further modified the value of fallows. Perennial fallows sown with meadow plants supported high plant species richness and bumblebee abundance. Old grassland fallows benefitted both butterflies in general, and butterflies and bumblebees with narrow niches and low dispersal capacities. The positive impacts were emphasized when long-term fallows were located in complex landscapes. High forest cover in the surrounding landscape increased plant species richness in perennial fallows. The breeding density of open farmland birds was highest in short-term meadow fallows in landscapes rich in perennial grasslands. Foraging edge birds preferred short-term meadow fallows in open landscapes and long-term grassland fallows in forested landscapes. Vegetation of annual fallow types game fields and landscape fields differed considerably from perennial fallows and other non-crop biotopes, thus enhancing landscape heterogeneity. My results show that the biodiversity benefits of fallows can be enhanced by adapting fallows to the landscape context and to specific conservation objectives. If the objective is to support species of conservation concern, managing long-term fallows in complex landscapes rich in perennial grasslands is probably the best strategy. Overall biodiversity can also be enhanced in short-term fallows, especially if they are sown with diverse seed mixtures of species that are not too competitive in field conditions. Depending on the sown species, short-term fallows provide good possibilities to enhance landscape heterogeneity and promote ecosystem services. Future studies should consider the specific roles of forest and perennial grasslands in driving the effectiveness of agri-environment schemes. In addition, the impacts of agri-environment schemes, including fallows, on realized ecosystem services should be investigated.Luonnonhoitopellot ovat kasvipeitteisiä, hoidettuja kesantoja, joiden tarkoitus on tuottaa ympäristöhyötyjä kuten luonnon monimuotoisuuden suojelua. Niiden perustamista ja hoitoa rahoitetaan Suomessa maatalouden ympäristöohjelman kautta. Vastaavia ympäristökesantoja on myös monissa muissa Euroopan maissa. Tutkimuksen tavoitteena oli selvittää, kuinka luonnonhoitopellon tyyppi ja ympäröivä maisema vaikuttavat luonnonhoitopellon eliölajistoon. Pyrkimyksenä oli myös arvioida, kuinka luonnonhoitopeltojen avulla voidaan parhaiten edistää erilaisia monimuotoisuuden suojelun tavoitteita: harvinaisten lajien suojelua, monimuotoisuutta yleisesti tai eliöiden tuottamia ekosysteemipalveluita. Tutkitut eliöryhmät olivat kasvit, perhoset, kimalaiset ja linnut. Mukana oli neljä luonnonhoitopeltotyyppiä: monivuotiset tyypit nurmiluonnonhoitopelto ja niittypelto sekä yksivuotiset maisemapelto ja riistapelto. Maiseman ominaisuuksista keskityttiin metsän ja monivuotisten nurmien määrään. Tulokset osoittivat, että luonnonhoitopeltotyypit erosivat eliölajistoltaan. Myös ympäröivä maisema vaikutti eri luonnonhoitopeltotyyppeihin eri tavoin. Vanhat nurmiluonnonhoitopellot, jotka sijaitsivat monimuotoisessa maisemassa, olivat tärkeitä elinympäristöjä varsinkin perhosille. Niillä eli myös vaateliaita ja heikosti leviäviä hyönteislajeja, jotka ovat erityisen herkkiä ympäristömuutoksille. Pellolla pesivät linnut puolestaan suosivat erityisesti nurmivaltaisessa maisemassa sijaitsevia niittypeltoja. Maisemasta riippumatta niittypelloilla oli monimuotoinen kasvillisuus ja runsaasti kimalaisia. Tämä selittyi niittypeltojen siemenseoksilla, jotka sisälsivät kukkivia kasveja ja heikosti kilpailevia heiniä. Yksivuotiset maisema- ja riistapellot erosivat kasvillisuudeltaan selvästi monivuotisista luonnonhoitopelloista ja muista viljelemättömistä ympäristöistä, minkä ansiosta ne lisäsivät maisematason monimuotoisuutta. Tutkimuksen perusteella pitkäaikaisia luonnonhoitopeltoja kannattaa perustaa metsien ja monivuotisten nurmien läheisyyteen. Lyhytaikaiset luonnonhoitopellot sopivat hyvin rikastuttamaan myös yksipuolista viljelymaisemaa. Siemenseoksesta riippuen niiden avulla voidaan lisätä maiseman monimuotoisuutta tai tukea yleisten lajien runsastumista edistäen näin ekosysteemipalveluita. Maatalouden ympäristötukitoimia tutkittaessa olisi syytä huomioida maiseman metsäisyyden ja monivuotisten nurmien määrän vaikutus toimenpiteiden tehokkuuteen. Myös ympäristötukitoimien vaikutus toteutuneisiin ekosysteemipalveluihin kuten viljelykasvien pölytyksen onnistumiseen tai biologiseen tuholaistorjuntaan kaipaa lisätutkimusta

Luonnon palvelut lautasella

Peer reviewe

Enhancing biodiversity of agricultural environment through environmental fallows

Luonnonhoitopellot lisättiin uutena vapaaehtoisena toimenpiteenä maatalouden ympäristötukeen vuonna 2009. Luonnonhoitopeltoihin kuuluvat monivuotiset nurmipellot sekä niitty-, riista- ja maisemakasveilla kylvetyt pellot. Toimenpiteen avulla pyritään suojelemaan ja lisäämään maatalousympäristön luonnon monimuotoisuutta sekä muun muassa vähentämään maatalouden ravinnehuuhtoumia. Vuonna 2010 luonnonhoitopeltoja oli yli seitsemän prosenttia Suomen viljelyalasta. Luonnonhoitopeltojen ympäristövaikutusten arvioiminen ja toimenpiteen kehittäminen on tärkeää, jotta toimenpiteeseen käytettävät varat eivät valu hukkaan. Tämän tutkimuksen tavoitteena oli selvittää, millainen merkitys luonnonhoitopelloilla on maatalousympäristön monimuotoisuuden kannalta; millaiset luonnonhoitopellot ovat monimuotoisuuden kannalta arvokkaimpia; ja kuinka toimenpidettä kannattaa kehittää. Kysymyksiin pyrittiin vastaamaan tutkimalla putkilokasvilajistoa, -lajirikkautta ja kasvillisuuden rakennetta erilaisilla luonnonhoitopelloilla, sekä vertaamalla luonnonhoitopeltojen kasvillisuutta pientareiden ja niittyjen kasvillisuuteen. Maastotyö luonnonhoitopelloilla tehtiin kesällä 2010 Uudenmaan ja Pohjois-Pohjanmaan ELY-keskusalueilla. Lisäksi tutkimuslohkoista kerättiin tietoja viljelijäkyselyn kautta. Niittypellot osoittautuivat tutkimuksessa lajirikkaimmaksi luonnonhoitopeltotyypiksi, mikä selittynee lähinnä sillä, että ne kylvetään heikosti kilpailukykyisellä siemenseoksella. Nurmi- ja niittypelloilla lohkon viljavuus korreloi negatiivisesti lajirikkauden kanssa. Lajikoostumukseltaan kaikki luonnonhoitopellot eroavat toisistaan sekä maatalousympäristön puoliluonnontilaisista elinympäristöistä, ja lisäävät siten monimuotoisuutta maisematasolla. Luonnonhoitopeltojen lajisto ei ole kuitenkaan suojelun kannalta erityisen arvokasta. Toimenpiteen maatalousympäristöä rikastuttavaa vaikutusta vähentää, että tällä hetkellä valtaosa luonnonhoitopelloista on monivuotisia nurmipeltoja. Luonnonhoitopeltojen siemenseoksia kehittämällä, perustamis- ja hoitomenetelmiä tutkimalla ja neuvontaan panostamalla voidaan lisätä luonnonhoitopeltojen arvoa niin luonnon, viljelijän kuin yhteiskunnankin kannalta.Environmental fallows were added as a new voluntary scheme to the agri-environmental programme in Finland in 2009. The scheme aims, among other things, to benefit farmland biodiversity by providing resources for wildlife, and to protect soil from erosion and nutrient leaching. There are four types of environmental fallows: long-term grassland, game crop field, landscape plant field and meadow plant field. In 2010, they covered in total over seven per cent of the field area in Finland. It is important to evaluate the impacts of environmental fallows on environment and develop the scheme, in order to make effective use of resources put into it. The goals of this study were to find out, how important environmental fallows are for biodiversity in agricultural landscapes; what kind of fallows are the most valuable for biodiversity; and how the scheme should be developed. In order to answer these questions, the species richness and composition of vascular plants as well as vegetation structure were surveyed on environmental fallows in Uusimaa and North Ostrobothnia regions in summer 2010. Additionally, the vegetation of environmental fallows was compared with the vegetation of semi-natural meadows and field edges surveyed in another study. Information on the study fields, e. g. parcel history, establishment and management, was collected through a farmer questionnaire. Meadow fields that are sown with low-competitive seed mixtures proved to be the most species rich of the environmental fallow types. On grasslands and meadow fields, the fertility of soil was negatively correlated to the number of species. In species composition the four types of environmental fallows differed from each others as well as from seminatural meadows and field edges. So, the scheme probably enhances diversity in landscape scale. However, there were few rare plant species on environmental fallows. Today, the big majority of the environmental fallows are long-term grasslands, which reduces their positive impact on landscape and biodiversity. The value of environmental fallows both for nature, farmers and society can be enhanced by developing seed mixtures and establishment and management methods as well as offering more advice for the farmers

Linking pollinator occurrence in field margins to pollinator visitation to a mass-flowering crop

Uncultivated field margins are important refugia for pollinating insects in agricultural landscapes. However, the spill-over of pollination services from field margins to adjacent crops is poorly understood. This study (i) examined the effects of landscape heterogeneity on pollinator occurrence in permanent field margins and pollinator visitation to adjacent mass-flowering turnip rape (Brassica rapa ssp. oleifera) in boreal agricultural landscapes, and (ii) tested whether pollinator abundance and species richness in field margins predict abundance and species richness of crop visitors. Pollinators visiting the crop were more affected by landscape heterogeneity than pollinators in adjacent margins. Species richness, total abundance, and the abundance of syrphid flies visiting the crop increased with increasing landscape heterogeneity, whereas, in field margins, landscape heterogeneity had little effect on pollinators. In field-dominated homogeneous landscapes, wild pollinators rarely visited the crop even if they occurred in adjacent margins, whereas in heterogeneous landscapes, differences between the two habitats were smaller. Total pollinator abundance and species richness in field margins were poor predictors of pollinator visitation to adjacent crop. However, high abundances of honeybees and bumblebees in margins were related to high numbers of crop visitors from these taxa. Our results suggest that, while uncultivated field margins help pollinators persist in boreal agricultural landscapes, they do not always result in enhanced pollinator visitation to the adjacent crop. More studies quantifying pollination service delivery from semi-natural habitats to crops in different landscape settings will help develop management approaches to support crop pollination.Peer reviewe

Effects of mixed pulp mill sludges on crop yields and quality

There is a great need for sustainable fertilisers and soil amendments, as current fertilisation practices negatively affect the environment. Pulp mill sludges (PMS) could provide a means to replace fertilisers made using non-renewable resources while adding slowly decomposing organic material to the soil and utilising nutrients from the forest industry. This study tested the effects of composted and lime-stabilised mixed PMS (CPMS and LPMS) on wheat (Triticum aestivum) yields and residual effect on oat (Avena sativa) yields in the boreal region. A two-year field experiment included two CPMS and two LPMS treatments all with additional mineral fertilisation, a mineral fertiliser treatment, and a zero-control treatment. All the fertilisers increased yields. There were no differences in crop yields between CPMS, LPMS and mineral fertiliser treatments. However, some quality characteristics and nitrogen (N) uptake were lower with all or some PMS compared with mineral fertilisation. This result suggests that part of the mineral fertilisation for cereals could be replaced by using PMS, but more information on N mineralisation from sludges is needed.peerReviewe

Probing the grounds: Developing a payment-by-results agri-environment scheme in Finland

Results-oriented approaches are widely regarded as an effective means to improving cost-effectiveness of agri-climate-environment schemes. We designed a hypothetical payment-by-results scheme for biodiversity conservation on environmental grasslands in Finland. The scheme would pay farmers a premium if the site contains a set number of indicator species, which were selected based on vascular plant surveys of the target habitat type. We presented the hypothetical scheme to 20 farmers and six experts (researchers, officials and advisors) in agricultural policy for their opinions on the payment-by-result approach generally and the hypothetical scheme specifically. The indicator species list proved suitable for identifying sites with high total species richness of vascular plants and also appeared feasible in the eyes of the farmers. Farmers were mostly positive about the approach and, mainly, thought their peers and society at large would receive it positively. The main concerns were about implementation, especially verifying the biodiversity results. People working for the national control body were the most critical and could not see how the hypothetical scheme could fit into the current institutionalised programme. Experience in other countries may provide solutions for overcoming such obstacles. The results are highly relevant for a discourse on social experimentation and cost-efficient delivery of public goods for public money.Peer reviewe

Crop type rather than production method determines functional trait composition of insect communities on arable land in boreal agricultural landscapes

To understand the potential consequences of arable land use changes for insect conservation and ecosystem functioning, it is fundamental to know how insect species with different functional traits respond to crop choice and production method.This study examined the effects of crop type and production method on functional traits of butterfly, bumblebee and carabid beetle communities using species abundance data from 78 fields in Southern Finland. Surrounding landscape composition was also accounted for. The studied traits were associated with dispersal capacity, habitat or diet specialization and phenology—the key determinants modifying species responses to agricultural disturbances and land use changes.Butterfly habitat breadth was narrowest and wingspan shortest in long-term fallows. Fallows also supported the highest share of butterflies overwintering in early development stages and bumblebees with late-emerging queens. The tongue length of bumblebees was longest in organic oat fields, probably due to flowering weeds with long corolla.For carabid beetles, the proportion of poor flyers and carnivores was highest in perennial crops and fallows. Carabid beetles overwintering as adults were relatively more abundant in organic than in conventional production, probably due to more intensive tillage in organic fields.In all insect groups, poor dispersers and/or specialists decreased with increasing arable land cover in the surrounding landscape.Increasing the area of long-term fallows and perennial crops and enhancing within-field plant diversity while maintaining landscape heterogeneity would promote insect species sensitive to agricultural disturbances and land use changes and their associated ecosystem services in boreal farmland

Pulp mill sludges as a solution for reducing the risk of mineral nitrogen leaching from agriculture

Nitrogen (N) from agricultural systems contributes to the eutrophication of waterbodies through leaching. Incorporating organic material with a high carbon-to-nitrogen (C/N) ratio, such as mixed pulp mill sludges (PMSs), into the soil in autumn could reduce the amount of leachable N. This study tested the potential of composted and lime-stabilised mixed PMSs (CPMS and LPMS) in reducing the concentration of mineral N in the soil, and thus the risk of N leaching from arable land in the boreal region using a two-year field experiment. To better understand the mechanisms of the PMSs for influencing mineral N concentration in soil, the impact of PMSs with different quality on the reactions of N in the soil was investigated in a laboratory incubation study. In the field experiment, nitrate-N (NO3--N) concentration was lower with PMSs compared to mineral fertilisation and the control during the first autumn and the following spring after PMS application. The undersowing of Italian ryegrass reduced the NO3--N concentration in the soil during the first autumn. In the incubation experiment, PMSs reduced the soil ammonium-N (NH4+-N) concentration at the beginning of the experiment and the soil NO3--N concentration throughout the experiment compared to a mineral fertiliser treatment and an organic fertiliser. Increased soil respiration in PMS-treated soils indicated increase in microbial activity, and thus immobilisation of soil NO3--N and NH4+-N due to PMSs addition. These results suggest that PMSs have the potential to reduce N leaching from agricultural soils. However, the immobilisation of N must be considered when planning the nutrient requirements of the following crops