Johannes Isselstein

University of Göttingen | GAUG · Division of Grassland Science

Einleitung und Problemstellung Die Milchviehhaltung erwirtschaftet aktuell über ihren Deckungsbeitrag den größten Anteil der landwirtschaftlichen Wertschöpfung der Region Wesermarsch (Niedersachsen). Weidehaltung ist eine verbreitete Nutzungsform auf den hier vorherrschenden kohlenstoffreichen Böden. Überlegungen zur Wiedervernässung dieser Böden a...

This study investigates within-site variation in the diversity and composition of aboveground vegetation and seed bank in intensively managed wet grasslands of north-western Germany, comparing field edges, field margins and field interiors. We tested the hypothesis that unfertilized buffer strips at field edges function as refugia of characteristic...

Virtual fencing (VF) is an emerging technology that creates virtual boundaries for livestock. Collars equipped with positioning systems, such as GPS, emit acoustic warning signals if an animal approaches the virtual fence and an electric impulse if it continues to move forward, deterring it from crossing the virtual fence. Compared to physical fenc...

One pillar of sustainable agriculture is grassland resilient and resistant to climate perturbation and capable of attaining multiple services. Novel or exotic and, so far, minor or underutilised plant species may become increasingly important against this background and exploration of such plant species seems of importance to maintain grassland fun...

Exploring the compatibility of solar energy and grass production on peat soil grasslands is needed to identify suitable solutions for energy provision and agricultural land use. In this context, a field experiment was established with permanent grassland on peat soil in North Germany. A free field photovoltaic system had been installed two years be...

Wolves (Canis lupus) are recolonizing Germany and confront pastoral farmers with the potential threat of livestock depredation. Protection measures such as wolf-deterring fences are considered indispensable for preventing carnivore attacks on livestock but require pro-active implementation by farmers. Drivers of farmers’ intention to adopt protecti...

In the context of climate change, the development and use of renewable energy is becoming increasingly important. However, with regard to free-field-photovoltaic (FFPV) systems the effective use of the land underneath the solar-modules (SM) remains an open question. When agricultural use and FFPV are combined, there is usually a trade-off between a...

Maintaining plant diversity in grasslands often depends on nutrient-poor soil conditions. Grazing by large herbivores can lead to a net nutrient removal, but spatially clumped deposition of excreta involves net nutrient input. We hypothesized that free-ranging red deer (Cervus elaphus) foraging in grasslands transfer nutrients concentrated in excre...

Virtual fencing (VF) is a modern fencing technology that requires the animal to wear a device (e.g. a collar) that emits acoustic signals to replace the visual cue of traditional physical fences (PF) and, if necessary, mild electric signals. The use of devices that provide electric signals leads to concerns regarding the welfare of virtually fence...

Hunting triggers behavioral responses in wildlife that may have important consequences for conservation and wildlife management. We studied movement and habitat selection in 51 global positioning system-collared red deer (Cervus elaphus) in response to 63 large-scale (x̄= 18.8 km 2) drive hunts conducted in 2015-2022 on a military training area in...

Predators can affect ecosystems through non‐consumptive effects (NCE) on their prey, which can lead to cascading effects on the vegetation. In mammalian communities, such cascading effects on whole ecosystems have mainly been demonstrated in protected areas, but the extent to which such effects may occur in more human‐dominated landscapes remains d...

Background Local sward dieback, especially in grasslands on peat soil, in response to the extreme 2018/2019 drought demonstrates climate vulnerability of intensive grasslands in northern Central Europe. Methods We explore the influence of microtopography, that is, the within‐field mosaic of depressions and elevated patches, on soil volumetric mois...

Energieerzeugung mit Hilfe von Freiflä-chen Photovoltaik (PV) Anlagen ist ein wichtiger Baustein auf dem Weg zur Energiewende. Die Flächeneffizienz ist im Vergleich zu Biogaserzeugung als hoch einzuschätzen. Darüber hinaus können Synergieleistungen ausgeschöpft werden, um eine mögliche Flächenkon-kurrenz abzumildern. Die Nutzung degradierter Moore...

Horses can contribute to the maintenance of grassland. To determine the potential contribution of grassland to horse nutrition, we investigated the seasonal variation of herbage on offer and its nutritional quality in an inventory on six practical horse farms in Central Germany during 2019. On all horse-grazed pastures compressed sward height (CSH)...

Rural livestock farmers in the semiarid and arid areas of Southern Africa face large uncertainties due to a high intraseasonal and year-to-year variability in rainfall patterns which affect forage resources. Creating resilient communal livestock farming systems will require the understanding of feed gaps as perceived by livestock farmers as well as...

Stable isotope analysis of 13 C and 15 N has been widely used to provide information regarding short-or long-term animal dietary composition as affected by changes in land or ecological system use. In complex mixed-crop −livestock systems, rangeland biomass, crop residues, and feedstuff contribute to livestock diets with high seasonal variations. P...

Grassland production based on cutting-only and an increasing frequency of prolonged periods of drought due to climate change could lead to decreased productivity in Lolium perenne. In field experiments, we tested whether Festuca arundinacea and Phleum pratense could be suitable alternatives to L. perenne on intensively managed grassland on clay, pe...

Grass swards in silvopastoral systems have a lower herbage production near trees than open grassland. This is related to a lower nitrogen (N) uptake in an area close to the tree lines. The N use efficiency for the whole field can then be improved when N input is spatially adjusted and the overall amount reduced. We performed a 2-year field experime...

Background Selective grazing creates stable patches of contrasting sward height, thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon (SOC) stocks. We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass (BGB) and SOC s...

Sustainable utilisation of the available grazing area acts to increase the profitability and productivity of livestock grazing and should consider animals and grass sward. The labour-intensive and time-consuming tasks of fencing, animal monitoring, and controlling forage availability on pasture are general obstacles to the wider implementation of g...

Extensive sheep pasturing in alpine regions has a long tradition and fulfils numerous sociological, economic and ecological functions. The effects of sheep grazing on the floristic composition and vice versa depend on various factors. Knowledge of potential interrelations is crucial to developing adequate management systems to maintain pasture prod...

Phytodiversität auf Grasland war in den letzten Jahrzehnten rückläufig. Im Hinblick auf aktuelle Herausforderungen, die durch den Verlust der Phytodiversität entstehen und durch den Klimawandel verschärft werden, ist eine Etablierung von bisher minoren Pflanzenarten wichtig, sodass simultan multifunktionelle Leistungen vom Grünland erbracht werden...

Predators can affect ecosystems through non-consumptive effects on their prey, which can lead to cascading effects on the vegetation. In mammalian communities, such cascading effects on whole ecosystems have mainly been demonstrated in protected areas, but the extent to which such effects may occur in more human-dominated landscapes remains disputa...

Knowledge of plant species distribution and abundance at different landscape scales and management‐induced degradation is essential for the conservation, planning, and enhancement of the biodiversity of rangelands. In this study, additive partitioning of species diversity based on contribution diversity was used to analyze the interaction of landsc...

Changing climatic conditions in north-western Europe require adaptations in management of ley grassland, requiring new grass-legume mixture designs in response to increased variability in precipitation and warmer summers. Evaluation of lucerne (Medicago sativa L.)-grass swards with the grasses cocksfoot (Dactylis glomerata L.) and tall fescue (Fest...

Lokale Nährstoffüberschüsse stellen eine globale Herausforderung und eine Bedrohung für intakte Ökosysteme dar. Um Stickstoffüberschüsse zu reduzieren und eine effiziente Ausnutzung von Nährstoffen (N und P) zu fördern, muss ein Großteil der landwirtschaftlichen Betriebe in Deutschland seit 2018 eine Stoffstrombilanz erstellen. Bei der Stoffstrombi...

In alley cropping, woody perennials are combined with agricultural crops or grassland in order to benefit from favourable interactions between trees and crops. Trees influence growth and senescence processes in grassland as well as plant chemical composition and plant water use. In a field experiment with grassland and alley‐cropped willow coppices...

Trees alter microclimate and radiation budget in alley cropping systems, which in turn change physiological processes of the grassland component. The influence of the trees on grassland growth depends on the climate zone as well as possibly on weather conditions during the respective growth interval. The proportion of shade-tolerant species in the...

Context In grazed grassland, the per area output of animal-source products usually declines with decreasing stocking rates because of lower herbage utilisation efficiency. Consequently, nutrient export is larger with increased stocking intensity, which should decrease the productivity in the long term. However, little information is available on lo...

Background Public interest in the way food is produced on the farm and processed along the food-production chain is increasing. The analysis of isotopic signatures ( ¹³ C) in cow tail hair provides a method to reconstruct the dietary proportion of maize in cow diets. Based on this, we further investigated whether there is a relationship between iso...

Intensively managed open croplands are highly productive but often have deleterious environmental impacts. Temperate agroforestry potentially improves ecosystem functions, although comprehensive analysis is lacking. Here, we measured primary data on 47 indicators of seven ecosystem functions in croplands and 16 indicators of four ecosystem function...

Semi-natural open habitats in Europe have been shaped by traditional land use practices, such as extensive mowing or livestock grazing. However, socio-economic transformations have led to the abandonment of many grassland and heathland areas and conservation management is now required to maintain these biodiverse habitats. Grazing by wild red deer...

Einleitung und Problemstellung Die Verbesserung des Tierwohls für Nutztiere ist ein gesellschaftlich und politisch verfolgtes Ziel. Eine adäquate Umsetzung kann zu einer positiveren öffentlichen Wahrnehmung der Landwirtschaft beitragen. Die Möglichkeit zur Ausführung natürlicher Verhaltensweisen ist eine der drei übergeordneten Dimensionen des Tier...

Permanent grassland provides various ecosystem services ranging from livestock feed provision to biodiversity preservation. With increased use of concentrate supplementation in dairy cow rations the importance of permanent grassland as the main feed resource in dairy production systems has decreased, although in Germany a large area of permanent gr...

Context. Continuous grazing in extensive grassland creates grazed and ungrazed patches, which are important for ecosystem service delivery. One possibility for optimising ecosystem services is to target a defined compressed sward height, which can be measured with rising plate meters supplied with internal global navigation satellite system (GNSS)...

In legume-based grassland, legumes supply the sward with nitrogen (N) from biological N2-fixation. Previous studies in silvopastoral systems have emphasized that legume proportions decline near trees which would cause spatial variation of the N supply and the concentration of N in the harvested herbage of grass swards between trees. In natural ecos...

Smallholder farming systems in southern Africa are characterized by low-input management and integrated livestock and crop production. Low yields and dry-season feed shortages are common. To meet growing food demands, sustainable intensification (SI) of these systems is an important policy goal. While mixed crop–livestock farming may offer greater...

Grassland degradation has been observed worldwide and is often a result of overexploitation or abandonment. Knowledge‐driven and precise grazing management is required to use grasslands' potential in a sustainable way. Information gaps lead to inefficiencies in grazing land management and ecosystem service provision. Rapid advances in automated sen...

Virtual fencing (VF) represents a way to simplify traditional pasture management with its high labour and cost requirements for fencing and to make better use of the 'beneficial' agronomic and ecological effects of livestock grazing. In this study, the VF technology (Ò Nofence, AS, Batnfjordsøra Norway) was used with Fleckvieh heifers to investigat...

Increased seasonal climatic variability is a major contributor to uncertainty in livestock-based livelihoods across Southern Africa. Erratic rainfall patterns and prolonged droughts have resulted in the region being identified as a climate ‘vulnerability hotspot’. Based on fieldwork conducted in the dry seasons in a semiarid region of South Africa,...

With the progressing intensification of agriculture and the subsequent vanishing of pollinating insects, the importance of semi-natural grasslands as insect habitats is increasing. However, such grasslands are threatened by succession following abandonment due to lack of economic profitability. Therefore, we investigated the effect of stocking rate...

Pastures fenced with electric wire fences are common practice for grazing and these physical fences emitting electrical impulses are largely accepted. However, the upcoming technology of virtual fencing (Nofence, Batnfjordsøra, Norway) raises animal welfare concerns because electrical impulses are emitted by a collar. In this study, we compared gro...

Grazing causes disturbance to the grass sward which is used as an indicator for management decisions based on herbage disappearance. Cattle grazing on a pasture move primarily to identify feeding stations that fulfil their daily dietary requirements. However, possible stress caused by new virtual fencing technology could also affect daily movement....

The methods used to assess diversity rely on time-consuming and laborious field samplings that limit their application at a regional scale. There is a need for methods that can be used to make rapid assessments of the composition of grassland plant communities. Data collected through citizen science have the advantage of covering large spatial and...

Under long-term extensive grazing, patches of different heights evolve as a consequence of preference for young and leafy vegetation (short <10 cm height) and avoidance of areas where the vegetation is mature and stemmy (tall >10 cm height). Among these patches the same plant species may survive site-by-site despite the divergent growing conditions...

Rising plate meters (RPM) are well established tools for pasture management to assess compressed sward height (CSH). Management of extensively grazed semi-natural grasslands for conservation purposes can be defined by target CSH. New and technically advanced RPMs like the Grasshopper (GH) need evaluation of CSH measurement performance in comparison...

LAI dynamics in an agroforestry system

Semi-natural habitats are vulnerable to eutrophication, which can result from atmospheric deposition. Maintaining habitat-specific nutrient conditions despite atmospheric inputs is a challenge for conservation. Grazing wild red deer (Cervus elaphus) is suggested as an alternative management measure for open habitats, but effects of red deer on nutr...

Current international efforts in development and research on virtual fencing systems

Eutrophication through atmospheric nutrient deposition is threatening the biodiversity of semi-natural habitats characterized by low nutrient availability. Accordingly, local management measures aiming at open habitat conservation need to maintain habitat-specific nutrient conditions despite atmospheric inputs. Grazing by wild herbivores, such as r...

Analysis of isotopic signatures of nitrogen (15N) is a widely used method for identifying and tracking pathways of N losses in agriculture. It is not yet clear how isotopic signatures in soil, plant and manures are related to N balances at the farm level. In the ‘Waterbuddies’ project, the N fluxes and N balances of 25 dairy farms in Northwest Germ...

Beweidung wildlebender Rothirsche hat sich als ein wirksames Instrument zur Offenlandpflege herausgestellt, welches den Erhaltungszustand von geschützten Lebensraumtypen positiv beeinflussen kann (e.g. RIESCH et al. 2020). Bisher war jedoch unklar, wie die Tiere die Nährstoffdynamik im Offenland beeinflussen. Um diese Frage zu untersuchen, wurden i...

supplement to Pfeiffer et al 2022 in Biogeosciences

Smallholder farming systems in southern Africa are characterized by low-input management and integrated livestock and crop production. Low yields and dry-season feed shortages are common. To meet growing food demands, sustainable intensi-fication (SI) of these systems is an important policy goal. While mixed crop-livestock farming may offer greater...

Smallholder farming systems in southern Africa are characterized by low-input management and integrated livestock and crop production. Low yields and dry-season feed shortages are common. To meet growing food demands, sustainable intensification (SI) of these systems is an important policy goal. While mixed crop-livestock farming may offer greater...

Legume-based forage plant mixtures are known to increase biomass production over the mixture species grown as pure stands (overyielding), which has partly been attributed to enhanced nitrogen availability by legumes. However, the relative importance of underlying processes of these positive diversity effects and their drivers are not fully understo...

Several scientists called for a new paradigm in animal nutrition by implementing feed diversity in otherwise homogeneously fed livestock production systems as former was shown to have a notable impact on animal productivity and health and the ecological footprint thereby decrease concerns regarding global food security from a societal perspective....

Analysis of isotopic signatures of nitrogen (¹⁵N) is a widely used method for identifying and tracking pathways of N losses in agriculture. It is not yet clear what drives the development of the isotopic signal over time after change of management in grasslands. In a three-year field experiment in cut grassland on a sandy soil in northwest Germany,...

Delayed harvest during different periods of the year may help to increase the multifunctionality in terms of simultaneous flowering resource and forage provision of ley grassland. Interaction effects of harvesting regime and the grass sward composition on herbage yield and quality were therefore investigated in two multispecies swards in the presen...

In southern Africa, livestock productivity in mixed crop-livestock systems is constrained by forage supply towards the end of the dry period. Opportunities to improve forage availability to close the temporal feed gap counteracting negative effects on production as well as on the environment need to be explored. A promising option might be the plan...

Livestock grazing can enhance biodiversity and ecosystem services in agricultural landscapes. In many parts of Europe, however, grazing has lost its importance, especially in the dairy sector. Large proportions of permanent grassland have been converted to arable land or intensified by fertilization and frequent defoliation. The disappearance of la...