Urs Schaffner's research while affiliated with HUYA Bioscience International and other places

Publications (166)

Article
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Parthenium weed (Parthenium hysterophorus L.) is a noxious weed and a flagship invasive that has been spreading throughout Israel and the Palestinian Authority since 1980. In other regions affected by this invader, parthenium weed has been managed through classical biological control releases of Epiblema strenuana, a stem-galling tortricid moth nat...
Article
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Besides direct water abstraction, natural water scarcity in semi-arid and arid regions may be further exacerbated by human-assisted changes in vegetation composition, including the invasion by non-native plant species. Water abstraction by the invasive Prosopis juliflora with native Senegalia senegal species was compared in the dry Great Rift Valle...
Article
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Soil microorganisms are major regulators of ecosystem functioning and are under threat from human-induced disturbances. Among these threats is grassland degradation, which is estimated to affect 49% of the grassland area worldwide, threatening biodiversity and ecosystem functioning. Yet, we currently lack an understanding of how grassland degradati...
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2022) Spatiotemporal trajectories of invasive tree species reveal the importance of collective action for successful invasion management ABSTRACT Biological invasions are complex processes requiring coordinated and spatially targeted management. This study assessed spatiotemporal tra-jectories and determinants of Prosopis cover in Baringo County, K...
Article
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Abstract The impacts of invasive alien plant species on native plants are generally well documented, but little is known about the mechanisms underlying their impacts on crop growth. A better understanding of immediate as well as legacy effects and of direct and indirect impacts of invasive alien plant species is essential for an improved managemen...
Article
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In weed biocontrol, the release of multiple candidates has been proposed as a way to increase herbivore load and thus impact on the target weed. However, the use of multiple herbivorous species may reduce overall herbivore load due to interspecific interactions. We assessed whether a combined application of two Pyropteron spp. (Lepidoptera: Sesiida...
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1. While most studies yield positive relationships between biodiversity (B) and ecosystem functioning (EF), awareness is growing that BEF relationships can vary with ecological context. The awareness has led to increased efforts to understand how contemporary environmental context modifies BEF relationships, but the role of historical context, and...
Chapter
This chapter describes the current status of IWM for grasslands. Its focus is on management practices available to influence transitions in a weed’s life cycle: from the soil seed bank to seedling establishment, from the seedling stage to the mature plant, and from the mature plant to the soil seed bank. We provide a conceptual approach to illustra...
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Sustainable land management (SLM) practices are key for achieving land degradation neutrality, but their continued implementation lag behind the progression of various forms of land degradation. While many scholars have assessed the drivers of SLM uptake for restoring land affected by desertification, drought, and floods (SDG 15.3 and partly SDG 2....
Article
Invasive non-native plants (INNP) cause severe impacts on nature and human well-being, and these are predicted to increase. While management tools have been developed to control early-stage invasions or to clean particular sites from INNP, they are only rarely available to halt and reduce large-scale invasions. Importation biological weed control (...
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Herbivorous insects play important roles in agriculture as pests or as weed biological control agents. Predicting the timing of herbivore insect population development can thus be of paramount importance for agricultural planning and sustainable land management. Numerical simulation models driven by temperature are often used to predict insect pest...
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Citation: Gentili, R.; Ambrosini, R.; Augustinus, B.A.; Caronni, S.; Cardarelli, E.; Montagnani, C.; Müller-Schärer, H.; Schaffner, U.; Citterio, S. High Phenotypic Plasticity in a Prominent Plant Invader along Altitudinal and Temperature Gradients. Plants 2021, 10, 2144.
Article
Although biological control agents (BCAs) are an effective tool for limiting the impact of invasive alien plants (IAPs), mismatch between the BCA and IAP, exacerbated by future climate change, may affect biocontrol efficacy and the likelihood of there being non-target effects. In a common-environment experiment, we measured leaf consumption, perfor...
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Grasslands are under severe threat from ongoing degradation, undermining their capacity to support biodiversity, ecosystem services and human well-being. Yet, grasslands are largely ignored in sustainable development agendas. In this Perspective, we examine the current state of global grasslands and explore the extent and dominant drivers of their...
Chapter
Unintentional biological control, defined as accidental introductions of natural enemies, exceeds in number of species those introduced intentionally by importation (classical) biological control. Several factors favor this: a general surge in international trade; lack of surveillance for species that are not associated with live plants or animals;...
Article
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We evaluated the potential of the European root-feeding moth Dichrorampha aeratana as a biological control agent for the invasive weed Leucanthemum vulgare (oxeye daisy) in North America and Australia. The taxonomic proximity of the ornamental Shasta daisy (Leucanthemum × superbum) to L. vulgare and its popularity in North America made finding suff...
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The context-depency of biological invasions makes it difficult to understand why some species become successful invaders and others not. Such understanding requires studying closely-related invasive and non-invasive alien taxa sharing the same introduction history in the same environment. We identified this unusual situation in Kenya where the indi...
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1. While the ecological impact of environmental change drivers, such as alien plant invasions, is relatively well described, quantitative social-ecological studies detailing how these changes impact multiple ecosystem services, and subsequently stakeholders, are lacking. 2. We used a social-ecological approach to assess how Prosopis juliflora (Pros...
Article
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Dense impenetrable thickets of invasive trees and shrubs compete with other water users and thus disrupt ecosystem functioning and services. This study assessed water use by the evergreen Prosopis juliflora, one of the dominant invasive tree species in semi-arid and arid ecosystems in the tropical regions of Eastern Africa. The objectives of the st...
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Accurate taxonomic identification of alien species is crucial to detect new incursions, prevent or reduce the arrival of new invaders and implement management options such as biological control. Globally, the taxonomy of non-native Prosopis species is problematic due to misidentification and extensive hybridization. We performed a genetic analysis...
Article
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Grassland degradation and the concomitant loss of soil organic carbon is widespread in tropical arid and semi-arid regions of the world. Afforestation of degraded grassland, sometimes by using invasive alien trees, has been put forward as a legitimate climate change mitigation strategy. However, even in cases where tree encroachment of degraded gra...
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Sustainably managed non-native trees deliver economic and societal benefits with limited risk of spread to adjoining areas. However, some plantations have launched invasions that cause substantial damage to biodiversity and ecosystem services, while others pose substantial threats of causing such impacts. The challenge is to maximise the benefits o...
Article
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Sustainably managed non-native trees deliver economic and societal benefits with limited risk of spread to adjoining areas. However, some plantations have launched invasions that cause substantial damage to biodiversity and ecosystem services, while others pose substantial threats of causing such impacts. The challenge is to maximise the benefits o...
Data
There is insufficient information regarding the factors affecting the environmental impacts of alien species. In particular, little is known about whether there is any relationship between the invasiveness (establishment and spread) of an introduced species and its per-capita impact. We experimentally assessed the relationship between the extent of...
Thesis
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As a result of an increasing rate of introductions of species in novel ranges, management of invasive alien plant species will be a continuous challenge. One curative method to control invasive alien plants is classical biological control. In conventional classical biological control programmes, extensive host range testing to assess potential risk...
Article
In 2013, the North American oligophagous leaf beetle, Ophraella communa LeSage (Coleoptera: Chrysomelidae), was found in Europe for the first time. Recent studies in Northern Italy and Southern Switzerland record extensive defoliation by O. communa on its preferred host, ragweed, Ambrosia artemisiifolia L. (Asteraceae, Tribe Heliantheae), and reduc...
Article
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Invasive alien species (IAS) can substantially affect ecosystem services and human well-being. However, quantitative assessments of their impact on human health are rare and the benefits of implementing IAS management likely to be underestimated. Here we report the effects of the allergenic plant Ambrosia artemisiifolia on public health in Europe a...
Article
Full-text available
There is insufficient information regarding the factors affecting the environmental impacts of alien species. In particular, little is known about whether there is any relationship between the invasiveness (establishment and spread) of an introduced species and its per capita impact. We experimentally assessed the relationship between the extent of...
Article
Full-text available
One of the biggest challenges in classical biological control of invasive weeds is predicting the likelihood of success. Ambrosia artemisiifolia, a North American plant species that has become invasive in Europe, causes economic losses due to health problems resulting from its huge amount of highly allergenic pollen and as a weed to agricultural cr...
Article
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While various aspects of classical biological control (CBC) of weeds, including non-target risk assessment, have been continuously improved in the past few decades, post-release monitoring remains neglected and underfunded. Detailed assessments of the population, community and ecosystem outcomes of CBC introductions, including reasons for success/f...
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Significant progress has been made in providing guidelines and recommendations for assessing the ecological niche, stage of invasion, and probability of invasive alien plant species (IAPS) potential distribution in space and time. We followed these recommendations by developing and comparing ordination and species distribution models (SDMs) of two...
Article
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Understanding the sustainability of social-ecological systems requires quantifying the relationships between ecosystem service supply and use. However, these relationships, and the influence of environmental change on supply and use, are poorly known. Here we apply a nested sampling design to analyse supply-use relationships in ten administrative u...
Article
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The ragweed borer, Epiblema strenuana (Walker, 1863), has a long history of use as a biological control agent against important weed pests in the family Asteraceae. Recently, E. strenuana has been reported feeding on the invasive perennials Ambrosia confertiflora and A. tenuifolia in Israel. The geographic location of Israel has raised concern over...
Article
Invasive alien plants reduce ecosystem service delivery, resulting in environmental, economic and social costs. Here we review the returns on investment from biological control of alien plants that invade natural ecosystems. Quantifying the economic benefits of biological control requires estimates of the reductions in ecosystem goods and services...
Article
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Determinants of the host ranges of insect herbivores are important from an evolutionary perspective and also have implications for applications such as biological control. Although insect herbivore host ranges typically are phylogenetically constrained, herbivore preference and performance ultimately are determined by plant traits, including plant...
Article
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Russian Olive, Elaeagnus angustifolia was introduced into North America primarily as a wind break and shade tree. Today it is listed as a noxious weed in the U.S. and Canada. During field surveys in the native range, the eriophyid mite, Aceria angustifoliae was identified as a promising biological control agent. Results from no-choice and open-fiel...
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Leucanthemum vulgare, a perennial forb native to Eurasia, has become invasive in several other parts of the world. Since there is a lack of methods suitable for sustainable management of this plant across invaded landscapes, a biological control project has been initiated in North America and Australia. We evaluated the potential of the root‐feedin...
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Species distribution models can predict the suitable climatic range of a potential biological control agent (BCA), but they provide little information on the BCA's potential impact. To predict high population build‐up, a pre‐requisite of biocontrol impact, studies are needed which assess the effect of environmental factors on vital rates of a BCA a...
Article
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1.Global change, such as exotic invasions, dramatically affects ecosystem functioning. However, the mechanisms behind the impacts are often unclear and despite extensive experimental work, we know little about the importance of biodiversity loss as a component of global change effects in real‐world ecosystems. 2.We disentangled several mechanisms b...
Article
Invasions can be genetically diverse, and that diversity may have implications for invasion management in terms of resistance or tolerance to control methods. We analyzed the population genetics of Russian-olive ( Elaeagnus angustifolia L.), an ecologically important and common invasive tree found in many western U.S. riparian areas. We found three...
Article
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Woody alien plant species have been deliberately introduced globally in many arid and semi-arid regions, as they can provide services and goods to the rural poor. However, some of these alien trees and shrubs have become invasive over time, with important impacts on biodiversity, ecosystem services, and human well-being. Prosopis was introduced in...
Article
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Fall armyworm (FAW), a voracious agricultural pest native to North and South America, was first detected on the African continent in 2016 and has subsequently spread throughout the continent and across Asia. It has been predicted that FAW could cause up to $US13 billion per annum in crop losses throughout sub-Saharan Africa, thereby threatening the...
Article
Common ragweed (Ambrosia artemisiifolia L.) is a widely distributed and harmful invasive plant that is an important source of highly allergenic pollen grains and a prominent cropweed. As a result, ragweed causes huge costs to both human health and agriculture in affected areas. Efficient mitigation requires accurate mapping of ragweed densities tha...
Article
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Land use/land cover (LULC) dynamics and the resulting changes in ecosystems, as well as the services they provide, are a consequence of human activities and environmental drivers, such as invasive alien plant species. This study assessed the changes in LULC and ecosystem service values (ESVs) in the Afar National Regional State, Ethiopia, which exp...
Preprint
Woody alien plant species have been deliberately introduced globally in many arid and semi-arid regions as they can provide services and goods to the rural poor. However, some of these alien trees and shrubs have become invasive over time, with important impacts on biodiversity, ecosystem services and human well-being. Prosopis was introduced in Ba...
Article
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The development of spatially differentiated management strategies against invasive alien plant species requires a detailed understanding of their current distribution and of the level of invasion across the invaded range. The objectives of this study were to estimate the current fractional cover gradient of invasive trees of the genus Prosopis in t...
Article
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Absract Insect herbivores use olfactory and visual cues during host plant finding. Although insect responses to these cues typically are assessed separately, in nature herbivores respond to olfactory and visual cues simultaneously. We demonstrate the functionality of a “double-stacked y-tube device” (D-SYD) to measure bioassay responses of a specia...
Article
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Abstract This study applied a generalized propensity score method to evaluate the impact of Prosopis invasion on Afar pastoralist and agro-pastoralist households’ annual per capita consumption expenditure, as a proxy of rural livelihoods. The analysis was based on cross-sectional survey data collected in mid-2016 from 250 households in the Afar Nat...
Article
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The success rate of weed biological control programs is difficult to evaluate and the factors affecting it remain poorly understood. One aspect which is still unclear is whether releases of multiple, genetically distinct populations of a biological control agent increase the likelihood of success, either by independent colonization of different env...
Article
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The North American common ragweed, Ambrosia artemisiifolia, which produces highly allergenic pollen, is invasive in different parts of the world, including Europe. In 2013, common ragweed in northern Italy was found attacked by another accidentally introduced species, the North American leaf beetle Ophraella communa, which is used for biological co...
Article
Full-text available
Biological control of weeds is a globally-recognised approach to the management of some of the most troublesome invasive plants in the world. Accidental introductions of agents accounted for all weed biological control agent establishments in the European Union until 2010, but these examples include some current or emerging control successes both l...
Article
One of the fundamental challenges of pre-release studies in classical biological weed control is to assess and predict the likelihood and consequences of non-target effects. Unless a candidate biological control agent is proven to be monophagous through conventional starvation and host-specificity tests in quarantine, open-field host range studies...
Article
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In weed biological control programs, pre-release host-specificity testing relies traditionally on no-choice and choice feeding, oviposition, and development tests. Rarely have they included detailed examination of behavioral responses to olfactory and visual cues of biological control candidates, although a better understanding of the mechanisms un...
Data
Principal Component Analysis (PCA) plots based on 17 traits measured on 536 plants of 62 Leucanthemum vulgare and L. ircutianum populations from the native (Eurasia, EU) and introduced (North America, NA) range grown in a common garden. (PDF)
Data
Results of flow cytometric analyses conducted with Leucanthemum seeds purchased from twelve US and one Canadian seed company. (PDF)
Data
Mean (± SE) trait values for 20 Leucanthemum vulgare and 21 L. ircutianum populations from the native range, Eurasia (EU) and 21 L. vulgare populations from the introduced range, North America (NA) grown in a common garden. (PDF)
Data
Locations of Leucanthemum vulgare and L. ircutianum populations sampled in Eurasia and North America. (PDF)
Article
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Species may become invasive after introduction to a new range because phenotypic traits pre-adapt them to spread and become dominant. In addition, adaptation to novel selection pressures in the introduced range may further increase their potential to become invasive. The diploid Leucanthemum vulgare and the tetraploid L. ircutianum are native to Eu...
Data
List of traits recorded for Leucanthemum vulgare and L. ircutianum grown in a common garden. (PDF)
Data
Eigenvectors showing correlations of traits with the first two principal components for the Principal Component Analyses (PCAs) on individual plants (see S4 Appendix) and on population means (see Fig 2). (PDF)
Data
Measurements taken on scanned mid-stem leaves of Leucanthemum vulgare (left) and L. ircutianum (right). (PDF)
Article
Full-text available
Biological control of weeds is a globally recognised approach to the management of some of the most troublesome invasive plants in the world. Accidental introductions of agents accounted for all weed biological control agent establishments in the European Union until 2010, but these examples include some current or emerging control successes both l...