Field Experiment In Switzerland Research Articles

Governments can nudge household solar energy adoption: Evidence from a field experiment in Switzerland

The use of photovoltaic (PV) systems on residential buildings is a key element in the societal transition to renewable energies. However, despite economic and ecological benefits, many homeowners struggle to adopt PV due to technical complexity, administrative burden, and cognitive biases such as inertia. There is also a lack of research on this issue and on how interventions informed by behavioral science could help increase adoption. We address this gap in the literature by conducting a preregistered field experiment involving 600 homeowners in Switzerland, testing whether two types of personalized behavioral interventions, one based on prosocial motives and one focusing on self-interest, lead to tangible actions towards PV adoption. The results from our pilot study show that both interventions substantially increase adoption behavior compared to a control group and a group that received only general information on PV. The intervention focusing on self-interest, which highlighted homeowners' missed revenues in the past year and thereby invoked loss aversion, yielded the largest effect. In summary, our study contributes to a better understanding of how public organizations can use behavioral interventions to promote renewables without large subsidies.

Unveiling everyday discrimination. Two field experiments on discrimination against religious minorities in day-to-day interactions.

In recent years-particularly since the beginning of the refugee crisis in 2015-the political debate about issues of Islamophobia and resentment of Muslims has gained new momentum. Our research contributes to the growing experimental literature focusing on these phenomena. Unlike most previous empirical investigations, the present study does not examine "large scale" discrimination against Muslim minorities in situations which occur only periodically throughout an individual's life (e.g., on the rental-, labor-, or partner market); rather, it sheds light on (minor) discrimination events that occur on a day-to-day basis. Such "everyday discrimination" has been shown to be particularly detrimental to physical and psychological health. Specifically, our research examines the effect of open displays of religious identification-wearing a Muslim headscarf-on everyday discrimination against female Muslims. We report the results of two natural field experiments in Switzerland designed to examine such forms of day-to-day discrimination. Study 1 focuses on differential sanctioning, whereas study 2 investigates differences regarding helping behavior. We found pronounced discrimination against women wearing a headscarf in two distinctly different types of everyday interactions. In both scenarios, headscarf-wearing confederates were treated less favorably than bare-headed ones: they were sanctioned more often for violating the "stand right, walk left"-norm on escalators and received less help when asking for a favor (borrowing a mobile phone for an urgent call).

Long-Term Effects of Organic Amendments on Soil Organic Matter Quantity and Quality in Conventional Cropping Systems in Switzerland

Increasing soil organic carbon (SOC) in agroecosystems is a promising solution to simultaneously address climate change mitigation, adaptation, and food security. Yet, the best management practices that could achieve these goals remain to be identified. Here, we analyze the long-term effects of application of green manure, cereal straw, farmyard manure, and cattle slurry on SOC in a 37 year long field experiment in Switzerland. The treatment effects were compared against control conditions that received only optimal mineral fertilization. More specifically, this study aimed at evaluating the effect of organic amendments on SOC accumulation and distribution in different soil particle-size fractions by means of a set of indicators about organic matter quality (biological reactivity, humification index) and microbial activity (extracellular enzyme activities). In the absence of organic matter input, application of mineral fertilizers alone resulted in the lowest SOC content and the highest humification index of the bulk soil organic matter. Among the organic amendments, cereal straw, farmyard manure, and cattle slurry promoted a higher SOC content and a lower humification index due to an increase of SOC in the clay-size fraction. The annual C accrual reached 4.4‰ per year over 37 years with farmyard manure. The higher biological reactivity measured for the green manure and cereal straw amendments was associated with higher soil enzymatic activities, while C retention coefficients decreased by at least 2.5 times compared to animal-derived amendments. The low availability of nutrients in green manure and straw amendments as suggested by the high phosphatase and N-acetylglucosaminidase activities may indicate a reduction in C retention of organic matter inputs due to nutrient microbial mining with plant-derived amendments.

Effect of management and weather variations on the greenhouse gas budget of two grasslands during a 10-year experiment

While many studies have measured the CO2 and N2O exchange of grassland ecosystems and analysed the influence of relevant drivers, only few reported the entire carbon budget over multiple years, which is most relevant for the net greenhouse gas (GHG) source or sink effect. When analysing eddy-covariance-based flux measurements for management and weather related drivers, this is commonly done by comparing either different measurement years at one site or data from different sites distributed regionally or globally. However this procedure makes it usually difficult to clearly attribute observed differences in the carbon exchange to management effects or meteorological drivers.In this study we present results of the carbon and GHG budget of a 10-year paired grassland field experiment in Switzerland comparing intensive and extensive management. We focus on the inter-annual variability of the entire 10-year dataset and especially on the effect of a renovation activity in the intensive field after seven years. By comparing the results of the paired plots, we attempted to disentangle the effects of management including renovation from the effect of seasonal weather conditions on the carbon and greenhouse gas budget. The annual carbon budgets of the two paired fields showed clear systematic differences attributable to the different management. The inter-annual variation (IAV) of the carbon budget was determined as residuals from linear trends. Due to the high correlation of the IAV between the two parallel fields, it was assigned mainly to variations in seasonal weather conditions. The total range of weather attributed variations of annual NECB values was similar in magnitude to the systematic management induced difference between the two fields (100–200 gC m−2 yr-1). In contrast to previous studies on grassland renovation, a large net carbon loss and enhanced N2O emission over 2–3 years was observed here. The excess N2O emission after renovation could be well explained by the IPCC default emission factor approach when considering the additional N input by plant residues and the net soil organic matter mineralisation. Concerning the total GHG budget effect the cumulated GHG uptake by the INT field in the first six years of the experiment was more than compensated by the release in the three post-renovation years.

Increasing brown hare (Lepus europaeus) densities in farmland without predator culling: results of a field experiment in Switzerland

In a field experiment in Northwestern Switzerland, we managed one part of each of four experimental areas in order to improve leveret (Lepus europaeus) survival and used the remaining part as control. The experimental areas were dominated by arable farming with a high diversity of different crops. Potential leveret predators were numerous and not controlled by gamekeeping. Management elements were wildflower patches, partly with an optimized antipredator design, and wider-sown cereals (to allow hares to enter the fields from May to July). We assumed that leverets are relatively safe in these two types of fields because these are seldom processed by agricultural machinery and potential leveret predators rarely forage there. The management lasted 7 years in two experimental areas and 3 years in the other two. Hare numbers and locations were monitored by spotlight counts, starting at least 3 years before the beginning of the experiment. In three out of the four experimental areas, we found a more positive development of hare densities in the managed area compared to the control area. Furthermore, the distribution of the hares within the experimental areas could be best described by a model including the percentage of wildflower patches, the percentage of arable land, and the percentage of cereals in wider-sown rows suggesting that hares predominantly occupied the surroundings of the management elements. We conclude that—irrespective of high predator densities—brown hare populations in agricultural landscapes with previously low hare densities can be considerably increased by offering a total area of about 3% wider-sown winter cereals or wildflower patches within the agriculturally used area.

The Impact of Personalized Information on Vote Intention: Evidence from a Randomized Field Experiment

Voting advice applications (VAAs) are voter information tools that millions of individuals have used in recent elections throughout the world. However, little is known about how they affect political behavior. Until now, observational studies of VAA have produced inconclusive results. Here we present the results from a randomized field experiment in Switzerland that estimates the causal effects of VAA use on voters’ vote intentions. Our results suggest that usage of the Swiss VAA smartvote strengthened the vote intention for the most preferred party and also increased the number of parties considered as potential vote options. These results imply that VAAs can influence voting behavior and that they can play an important role in electoral politics.

Equal Outcomes, but Different Treatment – Subtle Discrimination in Email Responses From a Correspondence Test in Switzerland

Abstract Correspondence tests on discrimination usually report only whether an applicant was invited for a job interview or not. Yet, data from a field experiment in Switzerland demonstrate that candidates with the same outcome are not necessarily treated equally. The paper complements correspondence test results with information on the time elapsed until candidates were contacted, as well as qualitative differences in invitation or rejection emails.

Two decades of no-till in the Oberacker long-term field experiment: Part I. Crop yield, soil organic carbon and nutrient distribution in the soil profile

This is the first in a series of papers describing the impact of two decades of no-till in the Oberacker long-term field experiment in Switzerland. The experiment was established in 1994 on a sandy loam and compares two tillage systems, conventional tillage with mouldboard ploughing (MP) and no-till (NT). Crops are grown in a six-year rotation, namely peas (Pisum sativum L.) − winter wheat (Triticum aestivum L.) − field beans (Phaseolus vulgaris L.) − winter barley (Hordeum vulgare L.) − sugar beet (Beta vulgaris L.) − silage maize (Zea mays L.). This study investigated the impact of the two tillage systems on (i) nutrient distribution and storage in the soil profile, (ii) the depth distribution of soil organic carbon and (iii) crop productivity. Soil samples were collected layer-by-layer following cultivation layers and natural soil horizons in a metal frame (0.5m×0.5m cross-sectional area) down to 0.5m depth. The layer boundaries were approximately 0.02, 0.05, 0.15, 0.25, 0.30, 0.40, and 0.50m for NT, and 0.15, 0.25, 0.30, 0.40, and 0.50m for MP. Soil organic carbon (SOC), total nitrogen (TotN), phosphorus (P), calcium (Ca), potassium (K), magnesium (Mg), pH, and bulk density were measured for each layer. The nutrient distribution was rather uniform within the plough layer in MP. In NT, there was strong stratification, with higher nutrient concentrations in the upper layers for TotN, K and Mg. This was associated with crop residue retention on the surface and reduced plant uptake due to low pH. In contrast, the distribution of P and Ca in NT was rather uniform in the 0–30cm layer, with a trend towards maximum concentrations at around 20cm depth. Total storage of nutrients per ha in the whole soil profile was similar in NT and MP for all nutrients. SOC stocks did not differ between NT and MP, although the depth distribution of SOC concentration was significantly different. The long-term average crop yield was slightly higher in NT than in MP, but the difference was not significant. Crop yield was significantly higher in NT for winter cereals (winter wheat, winter barley) and legumes (field beans and peas), but lower for root and tuber crops (sugar beet, potatoes). It can be assumed that the high crop yields in NT in the Oberacker long-term field experiment are due to the well-balanced crop rotation.

Two decades of no-till in the Oberacker long-term field experiment: Part II. Soil porosity and gas transport parameters

This is the second in a series of papers describing the impact of two decades of no-till in the Oberacker long-term field experiment in Switzerland. The first focused on crop yields, soil organic carbon and nutrient distributions in the soil, while this study investigated the impact on soil gas transport properties. The Oberacker long-term field experiment was established in 1994 on a sandy loam and compares two tillage systems, mouldboard ploughing (MP) and no-till (NT). Undisturbed soil cores were collected at 0.1 (topsoil) and 0.4m depth (subsoil) from both tillage treatments. Permanent grass (PG) strips located between the experimental plots were also sampled, as references. The soil cores were used for measurements of air-filled porosity (εa), air permeability (ka) and relative gas diffusion coefficient (Dp/D0) at five matric potentials ranging from ⿿30 to ⿿500 hPa. The results show that the soil pore system and gas transport properties of the NT soil were similar to those under PG for both topsoil and subsoil. In contrast, the soil under MP showed a clear stratification: εa, ka and Dp/D0 were higher than in NT and PG in the topsoil, but lower in the subsoil. The Dp/D0 vs. εa relationship was accurately described by a model derived from percolation theory. A linear relationship between log ka and log εa was found, but the slope was smaller than could be expected from percolation theory, in particular for subsoil, possibly because of the anisotropy of macropores. The pore system showed slightly higher specific diffusivity and much higher specific air permeability in the topsoil of MP than in NT or PG, but the relations were reversed in the subsoil. Thus it is highly important to consider both the topsoil and subsoil when tillage systems are evaluated.

Behavioral responses of voles along fences patrolled by natural predators

In a two year field experiment in Switzerland we tested if vole barriers combined with traps was a suitable tool to protect meadows and orchards from vole damage. We used a special kind of vole live trap that could be opened by terrestrial predators to feed on the captured animals. The experiment was designed to compare fences with traps, fences without traps and control lines without fences or traps. Predators preferred to move along fences with traps, which has been presented elsewhere. Voles on the other hand showed a preference for control lines as a general pattern but clear effects were masked by other factors. In practice, however, self service traps will attract natural predators and can therefore enhance the effect of simple fences to stop invading voles.

Privacy-Friendly Business Models for Location-Based Mobile Services

This paper presents a theoretical model to analyze the privacy issues involved in business models for location-based mobile services. We report the results of an exploratory field experiment in Switzerland that assessed the factors driving the net payoff to users of mobile businesses. We found that (1) the personal data disclosed by users has a negative effect on user payoff; (2) the amount of personalization available has a direct and positive effect, as well as a moderating effect, on user payoff; and (3) the amount of control over a user's personal data has a direct and positive effect, as well as a moderating effect, on user payoff. The results suggest that privacy protection could be the main value proposition in the B2C mobile market. From our theoretical model, we derive a set of guidelines to design a privacy-friendly business model pattern for thirdparty services. We discuss four examples to show how the mobile platform can play a key role in the implementation of these new business models.

Diversity of mitochondrial large subunit rDNA haplotypes of Glomus intraradices in two agricultural field experiments and two semi‐natural grasslands

Glomus intraradices, an arbuscular mycorrhizal fungus (AMF), is frequently found in a surprisingly wide range of ecosystems all over the world. It is used as model organism for AMF and its genome is being sequenced. Despite the ecological importance of AMF, little has been known about their population structure, because no adequate molecular markers have been available. In the present study we analyse for the first time the intraspecific genetic structure of an AMF directly from colonized roots in the field. A recently developed PCR-RFLP approach for the mitochondrial rRNA large subunit gene (mtLSU) of these obligate symbionts was used and complemented by sequencing and primers specific for a particularly frequent mtLSU haplotype. We analysed root samples from two agricultural field experiments in Switzerland and two semi-natural grasslands in France and Switzerland. RFLP type composition of G. intraradices (phylogroup GLOM A-1) differed strongly between agricultural and semi-natural sites and the G. intraradices populations of the two agricultural sites were significantly differentiated. RFLP type richness was higher in the agricultural sites compared with the grasslands. Detailed sequence analyses which resolved multiple sequence haplotypes within some RFLP types even revealed that there was no overlap of haplotypes among any of the study sites except between the two grasslands. Our results demonstrate a surprisingly high differentiation among semi-natural and agricultural field sites for G. intraradices. These findings will have major implications on our views of processes of adaptation and specialization in these plant/fungus associations.

Fungal community structure in soils of conventional and organic farming systems

Abstract Analysis of soil microbiota may help to describe and understand effects of agricultural management on soil quality. In the present study, effects on soil fungal communities were analysed in the DOK long-term agricultural field experiment in Switzerland. The temporally shifted 7-yr crop rotation allowed evaluation of the temporal stability of effects of organic and conventional farming systems. The influence of farming systems, crops and time on soil fungal community structures was compared between 2000 and 2007 using ribosomal internal spacer analysis. Richness of the fungal communities remained largely stable at the two different sampling dates, whereas the abundance of individual components changed. Despite this temporal stability, the most pronounced difference in the fungal communities was between the two sampling time points, whereas the influence of crops and farming systems were smaller. The time effect may be mainly induced by system-independent factors including changes in climatic conditions but also by system-dependent factors such as changes in preceding crops and farmyard manure characteristics between 2000 and 2007.

Book Reviews

Brian Erard of B. Erard and Associates reviews “Tax Compliance and Tax Morale: A Theoretical and Empirical Analysis” by Benno Torgler,. The EconLit Abstract of the reviewed work begins “Explores the reasons why citizens practice tax compliance and considers whether enforcement efforts can explain the high degree of compliance, focusing on the idea of tax morale. Discusses what we know about tax morale and compliance; speaking to theorists and searching for facts--tax morale and compliance in experiments; the importance of faith--tax morale and religiosity; tax morale and institutions; tax morale in Latin America; whether culture matters--a comparison of tax morale in the former East and West Germany; moral suasion--an alternative tax policy strategy?--evidence from a controlled field experiment in Switzerland; and tax amnesties and political participation. Torgler is Associate Professor in the School of Economics and Finance at Queensland University of Technology, Research Fellow with the Center for Research in Economics, Management, and the Arts, and Research Affiliate with the CESifo Research Network. Index.”

Response of soil microbial biomass and community structures to conventional and organic farming systems under identical crop rotations

In this study the influence of different farming systems on microbial community structure was analyzed using soil samples from the DOK long-term field experiment in Switzerland, which comprises organic (BIODYN and BIOORG) and conventional (CONFYM and CONMIN) farming systems as well as an unfertilized control (NOFERT). We examined microbial communities in winter wheat plots at two different points in the crop rotation (after potatoes and after maize). Employing extended polar lipid analysis up to 244 different phospholipid fatty acids (PLFA) and phospholipid ether lipids (PLEL) were detected. Higher concentrations of PLFA and PLEL in BIODYN and BIOORG indicated a significant influence of organic agriculture on microbial biomass. Farmyard manure (FYM) application consistently revealed the strongest, and the preceding crop the weakest, influence on domain-specific biomass, diversity indices and microbial community structures. Esterlinked PLFA from slowly growing bacteria (k-strategists) showed the strongest responses to long-term organic fertilization. Although the highest fungal biomass was found in the two organic systems of the DOK field trial, their contribution to the differentiation of community structures according to the management regime was relatively low. Prokaryotic communities responded most strongly to either conventional or organic farming management.

Moral suasion: An alternative tax policy strategy? Evidence from a controlled field experiment in Switzerland

With data gained from a controlled field experiment in Switzerland this paper analyses the effects of moral suasion on the timely paying and the timely filling out of the tax form 2001. Comparisons of different tax filing years and multiple regression estimations have been done using these two factors as dependent variables to check if there is a significant difference between the control group and the treatment group. In February 2002 the treatment group received a letter signed by the commune’s fiscal commissioner containing normative appeals. Results indicate that moral suasion has hardly any effect on taxpayers’ compliance behaviour. The strongest effect can be observed for the variable tax payments.

Effects of autumn kaolin and pyrethrin treatments on the spring population of Dysaphis plantaginea in apple orchards

Abstract:The impact of treatments with the pyrethrin insecticide Pyrethrum FS and the repellent kaolin product Surround® WP to control the autumn forms of Dysaphis plantaginea Pass. (Hom., Aphididae), a major insect pest of apple, was assessed in 1‐year field experiments in Switzerland. Single and multiple applications of pyrethrin and kaolin were tested at different dates after apple harvesting in autumn 2002 when sexuales of the rosy apple aphid were present. Repeated applications of Surround® WP in autumn significantly reduced the number of females in autumn and, consequently, the number of hatched fundatrices in spring. Single kaolin treatments were less effective. Unexpectedly, neither single nor multiple applications of the contact insecticide Pyrethrum FS had a knock‐down effect on females in autumn. However, pyrethrin significantly reduced the number of hatched fundatrices in spring. Neither pesticide completely controlled the rosy apple aphid but with a more detailed analysis of factors influencing the efficacy of autumn treatments a new approach to control this serious pest could be achieved.

Diversity and structure of AMF communities as affected by tillage in a temperate soil.

Arbuscular mycorrhizal fungi (AMF) were studied in differently tilled soils from a long-term field experiment in Switzerland. Diversity and structure of AMF communities were surveyed either directly on spores isolated from the field soil or on spores isolated from trap cultures, planted with different host plants. Single-spore cultures were established from the AMF spores obtained from trap cultures. Identification of the AMF was made by observation of spore morphology and confirmed by sequencing of ITS rDNA. At least 17 recognised AMF species were identified in samples from field and/or trap cultures, belonging to five genera of AMF--Glomus, Gigaspora, Scutellospora, Acaulospora, and Entrophospora. Tillage had a significant influence on the sporulation of some species and non- Glomus AMF tended to be more abundant in the no-tilled soil. The community structure of AMF in the field soil was significantly affected by tillage treatment. However, no significant differences in AMF diversity were detected among different soil tillage treatments. AMF community composition in trap cultures was affected much more by the species of the trap plant than by the original tillage treatment of the field soil. The use of trap cultures for fungal diversity estimation in comparison with direct observation of field samples is discussed.

Effects of augmentative releases of the coccinellid, Adalia bipunctata, and of insecticide treatments in autumn on the spring population of aphids of the genus Dysaphis in apple orchards

AbstractThe impact of augmentative releases of indigenous predators and insecticide applications to control the autumn aphid forms of the genus Dysaphis (Homoptera: Aphididae), major pest insects on apple trees, was assessed in one‐year field experiments in Switzerland. Eggs and larvae of the two‐spot ladybird beetle Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were released on 4‐year old apple trees in various numbers at five different dates in autumn 1998 when sexuales of the aphids were present. Additionally, Pyrethrum HP was sprayed at the same five dates to compare the effectiveness of these augmentative releases to a commonly applied insecticide. Augmentative releases of larvae before mid‐October significantly prevented the deposition of overwintering eggs by aphids of the genus Dysaphis and consequently reduced the number of hatched fundatrices in spring, 1999. There was a significant negative functional response among the number of released coccinellid larvae in autumn 1998 and the number of observed fundatrices on apple trees in spring 1999. Applications of Pyrethrum HP before mid‐October were more effective than augmentative releases of larvae of A. bipunctata. The release of coccinellid eggs had no impact on the number of fundatrices of the genus Dysaphis in the next spring because they did not hatch due to bad weather conditions. The weather conditions in autumn seemed to have an impact on the autumn migration of the winged aphids back to their primary host. The prevention of egg deposition of aphids in autumn is a promising control strategy and deserves further exploration for practical use.

Disease epidemics and plant competition: control of Senecio vulgaris with Puccinia lagenophorae

One approach to biological control of weeds is to relieve competition between crop and weed by inducing and stimulating epidemics of a pathogen on the weed. Results of a field experiment in Switzerland suggested that an epidemic of the rust fungus Puccinia lagenophorae could reduce losses in the crop celeriac (Apium graveolens) caused by competition with the annual weed Senecio vulgaris. Size hierarchy of celeriac increased in the presence of S. vulgaris and increased further by induction of a P. lagenophorae epidemic. The latter increase in size hierarchy could be explained by the spatial dynamics of the P. lagenophorae epidemic on S. vulgaris. Plants in the vicinity of the inoculum sources were infected earlier and more heavily than plants farther away causing variation in the impact of the pathogen on competition between celeriac and S. vulgaris. A positive relationship between infection of S. vulgaris by P. lagenophorae and celeriac yield could be observed. The study yielded insight into the impact of a disease epidemic on the competitive balance between two plant species and the results can be used to validate calculations about the number and spatial distribution of inoculum sources of P. lagenophorae required to control a S. vulgaris population.