Patch-Differentiation of Vegetation and Nutrient Cycling in an Extensive Pasture System

In extensive grazing systems, ‘patch-grazing’ may lead to the development of a mosaic structure consisting of short, frequently defoliated, and tall, infrequently defoliated patches. If spatial patterns of sward structure are stable over time, this may result in a long-term differentiation of botanical composition and matter fluxes between patch types within a pasture. Patch dynamics, botanical composition and topsoil nutrient concentrations of different patch types were investigated in a long-term grazing experiment in the Solling hills, Germany, where differentiated grazing intensities have been applied for 10 years. Continuously stocked beef cattle grazed to target sward heights of 6 or12 cm in a put-and-take system in replicated 1-ha paddocks. Time series of point-specific sward height measurements showed that patches were relatively stable within- and between-seasons. Botanical composition as well as soil phosphorus and potassium concentrations differed between short and tall patches. While grazing intensity influenced the frequency of short and tall patches within a pasture, differences between patch types were larger than those within the same patch type between different grazing intensities. The results highlight the importance of studying biodiversity as well as nutrient dynamics of extensive pastures in a patch-specific way. Through the development of pasture areas with different functionality, extensive grazing systems have the potential to maintain biodiversity while sustaining agricultural production

Wild Red Deer Benefit the Conservation of European Semi-Natural Open Habitats

Traditional land use practices have shaped European landscapes for millennia. Agricultural intensification and declining popularity of pastoral farming in the past century have resulted in a tremendous loss of extensively used open landscapes and associated biodiversity. Today, conservation management needs to prevent secondary succession of many open habitats. Large or inaccessible target areas unsuitable for conventional conservation measures might benefit from grazing by wild herbivores, which do not require fencing nor regular welfare monitoring. In a military training area in Germany, we studied the quantitative and qualitative effects of wild red deer in two protected open habitat types (lowland hay meadows and European dry heaths) based on grazing exclusion experiments over three years. Using movable exclusion cages, we showed that the amount of biomass annually removed by red deer was similar to the forage removal in livestock-based conservation grazing systems. Mown grasslands were particularly attractive to red deer owing to enhanced productivity and forage quality, suggesting that red deer grazing activities can be influenced by mowing. In addition, we compared the vegetation development in grasslands and heathlands with and without red deer grazing using open and permanently fenced plots. Grassland plant diversity decreased in fenced plots. In both habitat types, different structural vegetation characteristics, e.g. increasing sward and litter height, indicated successional developments when red deer grazing was excluded. Our results substantiate that allowing red deer access to open landscapes could not only alleviate potential conflicts with forestry, but can also promote open vegetation structure and diversity, thus providing a valuable contribution to the conservation management of semi-natural habitats

Impacts of cutting frequency and position to tree line on herbage accumulation in silvopastoral grassland reveal potential for grassland conservation based on land use and cover information

In agricultural grassland, high herbage utilisation efficiency (HEFF), which is the proportion of gross live-green herbage production that is utilised before entering senescence, is ensured by frequent defoliation. The decision upon which defoliation frequency to apply depends on the farming intensity. Assuming a reduced total herbage accumulation near trees in silvopastoral systems, frequent defoliations with high HEFF become less worthwhile—at least in specific spatial configurations. This makes an extensive management near trees an interesting option because it promotes other grassland-related ecosystem services such as biodiversity. The present study first analysed the interaction between defoliation frequency and position to trees on the total, dead and live herbage accumulation and the HEFF at two silvopastoral sites with short-rotation coppices in Germany. In addition, the total grassland–tree interface in Germany was assessed from land use and land cover maps of Germany based on satellite data to approximate the potential of grassland extensification near trees. The total herbage accumulation near trees declined by up to 41% but the HEFF was not affected by the position. Consequently, any intensification is not paid-off by adequate productivity and herbage quality in terms of HEFF and tree-related losses in herbage accumulation are expected up to a distance of 4.5–6 m. Applying a 4.5 m border on satellite data, we found that up to 4.4% (approximately 2200 km2) of the total grassland area in Germany is at a tree interface and potentially suitable for extensification. These findings indicate substantial potential for biodiversity conservation in grasslands with low trade-off for high-quality yield.Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347Peer Reviewe

Red Deer Browsing Decelerates Shrub Regrowth Despite Increasing Wolf Presence

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 (Cervus elaphus) can be a convenient alternative to laborious mechanical management or livestock grazing. Yet it remains unclear if free-ranging ungulates can counteract shrub growth sufficiently to maintain open habitats—especially with natural predators, i.e. wolves (Canis lupus), recolonizing Europe. To assess red deer effects on shrub regrowth after clearance, we installed a cohort of open and fenced plots (17 pairs) in 2016, when wolf presence in our study area (Grafenwöhr military training area, DE) was negligible. When wolf presence had become frequent in 2020, we set up a second cohort (41 paired plots). For both cohorts, the vegetation in the shrub and herb layer was significantly higher in fenced than open plots already after one year. Shrub height increased continuously and dead herbaceous biomass accumulated under red deer exclusion. Consequently, wild red deer can slow down shrub succession in open habitats even under increasing predation pressure. Regardless of wolf presence, a wildlife management that enables red deer to forage in open landscapes could thus reduce the required frequency of conservation management interventions

Sensor-based phenotyping of above-ground plant-pathogen interactions

Plant pathogens cause yield losses in crops worldwide. Breeding for improved disease resistance and management by precision agriculture are two approaches to limit such yield losses. Both rely on detecting and quantifying signs and symptoms of plant disease. To achieve this, the field of plant phenotyping makes use of non-invasive sensor technology. Compared to invasive methods, this can offer improved throughput and allow for repeated measurements on living plants. Abiotic stress responses and yield components have been successfully measured with phenotyping technologies, whereas phenotyping methods for biotic stresses are less developed, despite the relevance of plant disease in crop production. The interactions between plants and pathogens can lead to a variety of signs (when the pathogen itself can be detected) and diverse symptoms (detectable responses of the plant). Here, we review the strengths and weaknesses of a broad range of sensor technologies that are being used for sensing of signs and symptoms on plant shoots, including monochrome, RGB, hyperspectral, fluorescence, chlorophyll fluorescence and thermal sensors, as well as Raman spectroscopy, X-ray computed tomography, and optical coherence tomography. We argue that choosing and combining appropriate sensors for each plant-pathosystem and measuring with sufficient spatial resolution can enable specific and accurate measurements of above-ground signs and symptoms of plant disease

Limited role for extended maintenance temozolomide for newly diagnosed glioblastoma

Objective: To explore an association with survival of modifying the current standard of care for patients with newly diagnosed glioblastoma of surgery followed by radiotherapy plus concurrent and 6 cycles of maintenance temozolomide chemotherapy (TMZ/RT -> TMZ) by extending TMZ beyond 6 cycles. Methods: The German Glioma Network cohort was screened for patients with newly diagnosed glioblastoma who received TMZ/RT -> TMZ and completed >6 cycles of maintenance chemotherapy without progression. Associations of clinical patient characteristics, molecular markers, and residual tumor determined by magnetic resonance imaging after 6 cycles of TMZ with progression-free survival (PFS) and overall survival (OS) were analyzed with the log-rank test. Multivariate analyses using the Cox proportional hazards model were performed to assess associations of prolonged TMZ use with outcome. Results: Sixty-one of 142 identified patients received at least 7 maintenance TMZ cycles (median 11, range 7-20). Patients with extended maintenance TMZ treatment had better PFS (20.5 months, 95% confidence interval [CI] 17.7-23.3, vs 17.2 months, 95% CI 10.2-24.2, p = 0.035) but not OS (32.6 months, 95% CI 28.9-36.4, vs 33.2 months, 95% CI 25.3-41.0, p = 0.126). However, there was no significant association of prolonged TMZ chemotherapy with PFS (hazard ratio [HR] 5 0.8, 95% CI 0.4-1.6, p = 0.559) or OS (HR 5 1.6, 95% CI 0.8-3.3, p = 0.218) adjusted for age, extent of resection, Karnofsky performance score, presence of residual tumor, O-6-methylguanine DNA methyltransferase (MGMT) promoter methylation status, or isocitrate dehydrogenase (IDH) mutation status. Conclusion: These data may not support the practice of prolonging maintenance TMZ chemotherapy beyond 6 cycles. Classification of evidence: This study provides Class III evidence that in patients with newly diagnosed glioblastoma, prolonged TMZ chemotherapy does not significantly increase PFS or OS

Rotklee als alternative Eiweissquelle

Für Betriebe auf der Suche nach alternativen Eiweissquellen im Grundfutter kann der Rotklee eine sehr interessante Pflanze sein. Da Rotklee auch reich an Phytoöstrogenen (sekundäre Pflanzenstoffe, die in ihrer chemischen Struktur Sexualhormonen ähnlich sind) ist, sollten hohe Rationsanteile auf Dauer vermieden werden