Promoting soil functioning by maintaining soil microbial diversity and activity is central for sustainable agriculture. In viticulture, soil management often includes tillage, which poses a ...multifaceted disturbance to the soil environment and has direct and indirect effects on soil microbial diversity and soil functioning. However, the challenge of disentangling the effects of different soil management practices on soil microbial diversity and functioning has rarely been addressed. In this study, we investigated the effects of soil management on soil bacterial and fungal diversity as well as soil functions (soil respiration and decomposition) using a balanced experimental design with four soil management types in nine vineyards in Germany. Application of structural equation modelling enabled us to investigate the causal relationships of soil disturbance, vegetation cover, and plant richness on soil properties, microbial diversity, and soil functions. We could show that soil disturbance by tillage increased bacterial diversity but decreased fungal diversity. We identified a positive effect of plant diversity on bacterial diversity. Soil respiration showed a positive response to soil disturbance, while decomposition was negatively affected in highly disturbed soils via mediated effects of vegetation removal. Our results contribute to the understanding of direct and indirect effects of vineyard soil management on soil life and aids designing targeted recommendations for agricultural soil management.
Soil tillage or herbicide applications are commonly used in agriculture for weed control. These measures may also represent a disturbance for soil microbial communities and their functions. However, ...the generality of response patterns of microbial communities and functions to disturbance have rarely been studied at large geographical scales. We investigated how a soil disturbance gradient (low, intermediate, high), realized by either tillage or herbicide application, affects diversity and composition of soil bacterial and fungal communities as well as soil functions in vineyards across five European countries. Microbial alpha-diversity metrics responded to soil disturbance sporadically, but inconsistently across countries. Increasing soil disturbance changed soil microbial community composition at the European level. However, the effects of soil disturbance on the variation of microbial communities were smaller compared to the effects of location and soil covariates. Microbial respiration was consistently impaired by soil disturbance, while effects on decomposition of organic substrates were inconsistent and showed positive and negative responses depending on the respective country. Therefore, we conclude that it is difficult to extrapolate results from one locality to others because microbial communities and environmental conditions vary strongly over larger geographical scales.
•Plant communities and soil microbial communities responded strongly to tillage.•Communities were only slightly shifted by long-term N fertilization (0–150 kg N ha−¹).•Permanent cover in vineyard ...inter-rows supported C, N, K and Mg levels in the soil.•Soil treatment changed litter decomposition parameters.
Soil management strategies in viticulture should not only aim to optimize yield and quality of grapevines, but also sustain soil biodiversity and soil functioning. Here, we report on the combined effects of soil treatment and nitrogen fertilization on parameters related to soil fertility and litter decomposition, as well as plant, fungal, and bacterial communities in a long-term vineyard experiment, where these management practices have been applied since 1987. Plots in this vineyard (Hesse, Germany) were treated with different yearly amounts of nitrogen fertilizer (0, 30, 60, 90, 120, and 150 kg N ha−¹) with two types of inter-row soil treatment (tillage vs. permanent cover). We analyzed soil properties of the topsoil, decomposition parameters using the Tea Bag Index approach, the inter-row plant community, and microbial communities (bacteria and fungi) by next generation sequencing techniques.
Long-term tillage decreased soil carbon and nitrogen levels as well as some plant available nutrients, whereas soil pH and plant available phosphorus increased. Elevated amounts of nitrogen fertilization slightly increased soil carbon and nitrogen levels. Relative mass loss of tea bag content due to decomposition was decreased, while stabilization of labile litter components was increased by tillage, compared to permanent cover treatments. Plant community patterns were changed by soil treatment with tillage inter-rows exhibiting annual, ruderal species and being more diverse compared to permanent cover inter-rows. Relative abundance of several bacterial phyla and fungal orders responded strongly to soil treatment. Changes in soil pH and levels of phosphorus could partly explain the underlying mechanisms involved in shifts of bacterial and fungal communities, respectively. In contrast, long-term nitrogen fertilization only slightly shifted plant and microbial community composition. This study shows that over the long-term, soil treatment strongly affects soil functioning and biodiversity, exceeding the effect of even high nitrogen fertilization levels.
spittlebug nymphs produce a wet foam from anal excrement fluid, covering and protecting themselves against numerous impacts. Foam fluid contact angles on normal (26°) and silanized glass (37°) ...suggest that the foam wets various substrates, including plant and arthropod surfaces. The pull-off force depends on the hydration state and is higher the more dry the fluid. Because the foam desiccates as fast as water, predators once captured struggle to free from drying foam, becoming stickier. The present study confirms that adhesion is one of the numerous foam characteristics resulting in multifunctional effects, which promote spittlebugs' survival and render the foam a smart, biocompatible material of biological, biomimetic and biomedical interest. The sustainable 'reuse' of large amounts of excrement for foam production and protection of the thin nymph integument suggests energetic and evolutionary advantages. Probably, that is why foam nests have evolved in different groups of organisms, such as spittlebugs, frogs and fish.
Cover crops in vineyards do provide many important ecosystem functions, however wine growers are often reluctant to incorporate cover crops into their vineyard management as they are concerned about ...competition regarding water and nutrient availability. The objective of this study was to define the effects of three standard inter-row vegetation management strategies on vine growth and grape quality in different European regions. We hypothesize that general patterns of responses to different inter-row management can be identified across European vine growing regions independent of local climate and soil conditions. Data were collected in 2016 and 2017 in commercial vineyards located in five European temperate wine growing regions directly comparing standard inter-row vegetation management strategies in parallel in vineyards ranging from cover crops to bare ground through tillage or herbicide application. Vegetation management strongly influenced leaf chlorophyll content, shoot pruning weight and yeast assimilable nitrogen (YAN) in grape juice. Across countries, grape varieties and varying soil conditions, YAN consistently showed higher values in grapes separated by bare ground inter-rows as compared to inter-rows with a permanent vegetation cover. Other grape quality parameters, total soluble solids, total titratable acidity and berry weight were not or inconsistently affected across countries, preventing the prediction of generalized trends. We also observed higher values of soil organic matter in complete vegetation inter-rows. In conclusion, we identified general effects of inter-row vegetation management on vine vigor and grape quality across countries and grape varieties in different pedo-climatic conditions. Our study provides general response patterns as a basis for functional studies to develop local inter-row vegetation management strategies.
•Across European vineyards, inter-row vegetation decreased vine vigor and grape nitrogen.•Vine response was conserved across pedo-climatic conditions and grape varieties.•Pruning weight and leaf chlorophyll content increased with soil tillage.•Total soluble solids and titratable acidity were not influenced by inter-row management.•Soil organic matter decreased with soil tillage or herbicide application.
The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of ...coherent large‐scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass‐loss rates and stabilization factors of plant‐derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy‐to‐degrade components accumulate during early‐stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass‐loss rates and stabilization, notably in colder locations. Using TBI improved mass‐loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early‐stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.
Based on empirical litter decomposition data obtained at an unprecedented spatial scale, we demonstrate that initial mass‐loss rates and later stabilization of litter‐derived carbon can be decoupled, which can result in context‐dependencies in how warming affects ecosystem carbon cycling in colder environments, where environmental change is more extreme. Further, we note that variation in empirical litter mass‐loss data can result from a mixture of initial mass‐loss rates, stabilization or even longer term dynamics. Hence, we believe that the TBI proxies and their underlying global database provide powerful tools to aid process understanding as well as to train and improve global carbon models, especially regarding the role of climate context‐dependencies and interactions.
Increasing breast muscle percentage by selection for breast layer thickness (muscle and skin) of living ducks by needle probe improves carcass quality as could be demonstrated by experiments and by ...applied breeding programs. In addition direct selection for individual feed conversion ratio can increase the efficiency of duck meat production. Divergent selection for feed conversion ratio from the age of 4 – 7 weeks over 11 generations has differentiated the feed efficiency by about 25 %. Causes for the reduction in feed conversion ratio are lower fat content of carcass, lower locomotor activity, higher enzymatic activity (alkaline phosphatase and creatinkinase in blood plasma) and better feed protein utilization. Because of lower feed consumption in the line selected for lower feed conversion ratio the emission of nitrogen and phosphorus via manure was reduced by about 39 and 26 %, respectively. That means, selection for better feed efficiency is not only an important economical but also an important ecological factor.
Polymer transistors are being intensively developed for next-generation flexible electronics. Blends comprising a small amount of semiconducting polymer mixed into an insulating polymer matrix have ...simultaneously shown superior performance and environmental stability in organic field-effect transistors compared with the neat semiconductor. Here we show that such blends actually perform very poorly in the undoped state, and that mobility and on/off ratio are improved dramatically upon moderate doping. Structural investigations show that these blend layers feature nanometre-scale semiconductor domains and a vertical composition gradient. This particular morphology enables a quasi three-dimensional spatial distribution of semiconductor pathways within the insulating matrix, in which charge accumulation and depletion via a gate bias is substantially different from neat semiconductor, and where high on-current and low off-current are simultaneously realized in the stable doped state. Adding only 5 wt% of a semiconducting polymer to a polystyrene matrix, we realized an environmentally stable inverter with gain up to 60.
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