Abstract
A field experiment was carried out during the winter season of 2020-2021 in the Habbaniyah district, west of Baghdad, to study the response of forage yield and quality of oats
Avena sativa
...L. var. Shifaa to planting distances and mowing dates. A split plots arrangement according to the RCBD at three replications was used. The main plots included planting distances, while the subplots included the mowing dates. The study’s results indicated that the planting distance of 25 cm between lines was significantly superior in the green forage yield and fiber percentage 12.00 ton ha
-1
and 37.61%, respectively. In comparison, the planting distance of 20 cm between lines was significantly superior in the protein percentage 12.34%. As for the mowing dates, the mowing after 70 days was selected substantially in the forage yield and fiber percentage. The mowing after 50 days was significantly superior in protein percentage 12.28%. The interaction between studied factors significantly affected the most studied traits.
Purpose
Mowing may exert profound influences on nutrient acquisition strategies of herbaceous species due to the nutrient removal along with the mown plants. Nutrient uptake by roots and nutrient ...resorption from senescent leaves, are two main nutrient acquisition strategies of perennial herbaceous species. However, few studies have considered both nutrient acquisition strategies in exploring the effects of long-term mowing on the nutrient acquisition of perennial herbs.
Methods
We measured root traits of absorptive roots and leaf nitrogen resorption efficiency (NRE) of seven herbaceous species with different plant height on a long-term mowing experimental platform (2003-2020) in a temperate steppe.
Results
We found that root traits of tall and short species had little response to long-term mowing. While, mowing exerted opposite effects on leaf NRE of the two plant groups, i.e., mowing significantly decreased the NRE of tall species, but increased that of short species (except for
Potentilla acaulis
). Furthermore, root absorption capacity (indicated by root traits) was positively correlated with leaf NRE for tall species in control plots, but mowing eliminated this relationship. In contrast, for short species, root traits and leaf NRE had no correlation in control plots, while, mowing led to synergic relationship between root absorption capacity and leaf resorption rates.
Conclusions
Our results suggested that perennial herbs changed the relationships between alternative resource acquisition strategies in response to long-term mowing in temperate steppe. These findings provide new perspectives for understanding the adaptation of herbaceous species to mowing in the temperate steppe.
Flower margins are widely adopted as agri-environment measure (AEM) to enhance farmland biodiversity. However, perennial flower margins need appropriate mowing schemes to manage succession, ...especially in regions with high nitrogen depositions, and current schemes inadequately address the needs of arthropods, including pollinators. Effective management should provide floral diversity with staggered flowering times, creating varied sward structures for diverse habitats that support shelter, nesting, and mating sites.
To address these challenges, a novel mowing method, called 'Three-strip management,' is proposed. This method involves dividing the margin into three strips using curved instead of straight mowing lines. During each cycle, one third remains unmown for shelter, while clippings are removed to lower soil nutrient status and reduce succession. The use of overlapping curved mowing lines aims to maximize variety in patterns, fostering spatio-temporal variation in the (re)growth of perennials and swards. Unlike Regular rotational management, multiple uneven parts are kept unmown over winter, increasing the number of subzones in different mown states over successive years.
In this study, field trials comparing Three-strip management with Regular rotational management reveal positive effects especially during the second year, including higher bee abundance and diversity. Plant-pollinator networks also demonstrate increased interactions. While the study focuses on bees, the potential of the Three-strip management to support other beneficial insects is discussed. Given declining insect populations in agricultural landscapes, this paper offers insights into enhancing perennial flower margins as AEM to support pollinator populations. The novel Three-strip management presents a promising strategy for balancing management needs with diverse insect requirements, contributing to sustainable biodiversity conservation in agricultural settings.
Abstract
The objective was to determine how mowing date affected forage availability and quality. Cool season grass plots were randomly assigned to 4 treatments (n=2): mowed on day 1 (M1), mowed on ...day 15 (M15), mowed on day 29 (M29), and not mowed (NM). During the 56-day experiment, forage heights were measured using a rising plate meter to determine forage availability and samples were clipped for proximate analysis. The MIXED procedure of SAS was used to analyze data. On day 14, CP in M1 was 37.5% greater (P = 0.05) than the composite of M15, M29, and NM. However, the composite of M15, M29, and NM had greater (P = 0.02) forage availability than M1 on day 14. On day 28, M15 had greater (P = 0.02) ADF than M1, while the composite of M29 and NM was intermediate and not different than other treatments. There was also a treatment effect (P < 0.01) on forage availability on day 28; the composite of M29 and NM was greatest followed by M1 and M15, respectively. On day 42, the NDF of M29 was greater (P = 0.01) than M1, M15, and NM. Decreased CP was observed (P = 0.05) for NM compared with M1, M15, and M29 on day 42. Forage availability was different (P < 0.01) for all treatments on day 42 with NM being the greatest followed by M1, M15, M29, respectively. On day 56, NM tended (P = 0.08) to have the greatest DM, but there was no difference (P ≥ 0.31) in NDF, ADF, and CP. Forage availability was different (P < 0.01) for all treatments on day 56 with NM being the greatest followed by M1, M15, M29, respectively. In conclusion, mowing reduced forage availability as expected, but it also increased CP on day 14 and 42.
Ground‐nesting wild bees provide essential pollination services in agroecosystems, but they are jeopardized by intensive agricultural management. To mitigate such negative impacts, agri‐environment ...schemes have been implemented. While the success of enhancing floral food resources is relatively well studied, the role of agri‐environmental schemes in providing suitable nesting habitat remains underexplored.
We studied the effectiveness of meadow extensification according to the Swiss agri‐environment scheme in promoting nesting of ground‐nesting bees. Using a paired design, we quantified their nests during four rounds (March–June) in pairs of nine randomly selected extensively (i.e. no fertilizer input, postponed first mowing) and nine intensively managed meadows with similar soil properties, slope, exposure and landscape context. Nest numbers and vegetation characteristics were surveyed in areas of 250 m2. Vegetation properties were also assessed in 0.5 × 0.5 m plots around nest locations and randomly selected locations without nests within each meadow to assess their role as drivers of nesting incidence (nest presence/absence) at this plot scale.
We found substantially higher nest numbers of ground‐nesting bees in extensively (mean ± SE per sampling round = 46.8 ± 14.2) compared to intensively managed meadows (0.8 ± 0.3; no nests in three of nine intensively managed meadows). Extensively managed meadows harboured nests of several dominant crop pollinator species, including aggregations of, for example, Lasioglossum malachurum contributing to high nest densities in some of them. Number of nests was negatively related to grass cover and vegetation height, which were lower in extensively compared to intensively managed meadows. Plot‐level nesting incidence increased with bare ground and moss cover, and decreased with grass cover.
Synthesis and applications. Our study shows that extensively managed meadows are better nesting habitats for ground‐nesting bees than intensively managed meadows, if reduced management intensity is associated with altered vegetation characteristics such as reduced grass cover and vegetation height, and small‐scale availability of bare ground, driving these effects. This highlights that maintaining and promoting extensive management of meadows can promote ground‐nesting wild bees, including dominant crop pollinators, not only by enhancing floral resources but also by improving nesting opportunities in agroecosystems.
Our study shows that extensively managed meadows are better nesting habitats for ground‐nesting bees than intensively managed meadows, if reduced management intensity is associated with altered vegetation characteristics such as reduced grass cover and vegetation height, and small‐scale availability of bare ground, driving these effects. This highlights that maintaining and promoting extensive management of meadows can promote ground‐nesting wild bees, including dominant crop pollinators, not only by enhancing floral resources but also by improving nesting opportunities in agroecosystems.
Philaenus spumarius (Linnaeus, 1758) (Hemiptera: Aphrophoridae) is considered the main vector of Xylella fastidiosa (Wells Raju et al. 1986) (Xathomonadales: Xanthomonadaceae), agent of the Olive ...Quick Decline Syndrome in Southern Europe. To limit the spread of the disease, it is of primary importance to identify effective control measures against the vector. Besides chemical control, cultural practices could potentially help reducing vector activity and population density. Here, we tested the effectiveness of three different ground cover management practices in controlling vector populations in olive groves in the Abruzzo region (Central Italy). We compared tillage (two tillage operations in spring followed by two cuts in summer), frequent mowing (four cuts from spring to summer) and a control (two cuts in summer) by sampling vectors both in the ground vegetation and in the tree canopy. In late spring, after the peak of the population, tillage reduced P. spumarius density by 60%, while frequent mowing only reduced the density by 20% compared to control plots. The differences tended to disappear with time. The treatments had the same effect on the vector density in both the ground vegetation and tree canopy. The vectors were more concentrated in the ground cover at the beginning of the season while in summer both the canopy and ground vegetation had the same vector density. Our findings suggest that tillage is a viable option for the containment of P. spumarius, as frequent mowing did not achieve sufficient control efficacy.
For the restoration of biodiversity in agricultural grasslands, it is essential to understand how management acts as an ecological filter on the resident species. Mowing constitutes such a filter: ...only species that possess functional traits enabling them to withstand its consequences can persist in the community. We investigated how the timing of mowing modulates this filtering effect for insects. We predicted that two traits drive species responses. Species with larval development within the meadow vegetation will suffer more from mowing than species whose larvae develop in or on the ground, or outside the meadows, while species with a later phenology should benefit from later mowing. We conducted a five-year experiment, replicated at 12 sites across the Swiss lowlands, applying three different mowing regimes to lowintensity hay meadows: (1) first cut of the year not earlier than 15 June (control regime); (2) the first cut delayed until 15 July; and (3) leaving an uncut grass refuge on 10–20% of the meadow area (after earliest first cut on 15 June). Before the first cut in years 4 or 5, we sampled larvae of Lepidoptera and sawflies, and adults of moths, parasitoid wasps, wild bees, hoverflies, ground beetles, and rove beetles. Overall, before the first cut of the year, abundances of species with vegetation-dwelling larvae were higher in meadows with delayed mowing or an uncut grass refuge, with some taxon-specific variation. In contrast, species whose larval development is independent of the meadow vegetation showed no differences in abundance between mowing regimes. Species richness did not differ among regimes. For species with vegetation-dwelling larvae, a fourth-corner analysis showed an association between early phenology and the control regime. No associations were found for the other functional groups. Our results show that slight modifications of mowing regimes, easily implementable in agri-environmental policy schemes, can boost invertebrate abundance, potentially benefitting insectivorous vertebrates.
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