Yield determination in olive hedgerow orchards. I. Yield and profiles of yield components in north–south and east–west oriented hedgerows

A study of the vertical distribution of flowering and fruit set and of components of yield (fruit numbers, fruit size, and fruit oil content) was maintained for 2 years in N–S- and E–W-oriented olive hedgerows of comparable structure (row spacing 4m, hedgerow height to 2.5 m, width c. 1m) near Toledo, Spain (39.98N). Mean yield of the N–S orchard was 1854 kg oil/ha without difference between sides or years. Yield of the E–W orchard was greater in 2006, producing 2290 kg/ha, but only 1840 kg/ha in 2007, the same as the N–S orchard. The S side of the E–Worchard yielded more (59%) than the N side in 2007. In both orchards and years, most fruit was produced at 1.0–2.0m height and fruit density was the most influential component in these differences, reflecting more intense bud initiation in these upper layers. Other components that determined fruit number, fertile inflorescences, fruits per fertile inflorescence, and fruit drop were not significantly different between layers. Fruit characteristics depended on hedgerow position. In both N–S and E–W hedgerows, fruit high in the hedgerow was the largest, most mature, and with highest oil content. These differences were more marked in N–S than in E–W hedgerows. Fruit growth and development were concentrated from the middle of September until the end November. Oil content per fruit increased linearly during that period when 65% of final oil content was accumulated. Similar patterns were observed between sides. The results of yield and yield profiles are discussed in the general context of light interception. The results suggest the importance of hedgerow porosity, and distinct penetration patterns of direct-beam radiation through N–S and E–W hedgerows, as the basis for explanation of the high yield of the N side of E–W hedgerows

Contributions of Hedgerows to People: A Global Meta-Analysis

David García de León et al. (2021) 'Contributions of Hedgerows to People: A Global Meta-Analysis', Frontiers in Conservation Science, 2. doi:10.3389/fcosc.2021.789612.Hedgerows are linear landscape features of woody vegetation usually located around agricultural fields. An increasing number of studies have addressed the effects of hedgerows on biodiversity and ecosystem services. This study is aimed to synthesize these effects and compare the levels of biodiversity and ecosystem services in farmland with hedgerows and (1) farmland without hedgerows and (2) nearby natural habitat at the global scale. We hypothesized that farmland with hedgerows (1) enhances biodiversity and ecosystem services as compared to farmland without hedgerows but (2) supports lower levels of biodiversity and ecosystem services than natural habitat. Our systematic literature review retained 835 observations from 170 primary studies, which were analyzed following the standard methodology in meta-analyses. Our results partially support both hypotheses. Farmland with hedgerows exhibited higher levels of biodiversity and provisioning services than farmland without hedgerows (H1). Farmland with hedgerows provided similar levels of biodiversity (edge effects) but lower levels of ecosystem services than natural habitat (H2). The effects of hedgerows on biodiversity and ecosystem services depended on control ecosystem type (grassland/meadow or forest/woodland) but were largely independent of climate type (temperate or tropical) and the focus of spatial scale (field or landscape). In conclusion, conservation and restoration of hedgerows contribute to people in several ways by enhancing biodiversity and multifunctionality in agricultural landscapes.Comunidad de MadridUniversidad de Alcal

Plant Diversity in Natural and Cultivated Hedgerows in the Laminga Area of Jos East, North Central Nigeria

Hedgerows are important semi-natural environments in agricultural landscapes. A study was carried in the Laminga Area of Jos East in North Central Nigeria to investigate the vegetation composition of farmland hedgerows and to compare plant species composition and diversity between natural and cultivated hedgerows. Twenty (20) farmland hedgerows (13 cultivated and 7 natural hedgerows) were sampled. At each farmland, sampling was conducted within a 50 x 1m area of the hedgerow. Plant species diversity was calculated using Shannon – Weiner’s diversity index and plant species evenness was calculated using Pileou’s evenness index. One-way-ANOVA was used to compare plant species richness, evenness and diversity between natural and cultivated hedgerows.  The Plant community structure of the hedgerow types was characterized using Non-Metric Multidimensional Scaling (NMDS) ordination method. A total of 12,555 individual plants were recorded during the survey. These were divided into 100 species and 40 families. Plant species richness and evenness was not significantly different between the Natural and Cultivated hedgerows while the plant diversity was significantly higher in the Natural hedgerows than the Cultivated hedgerows. The hedgerows studied were prosperous in biodiversity. Hedgerows play several ecosystem functions and are highly important in conserving biodiversity. Keywords: Agricultural landscapes, biodiversity, ecosystem, farmland, hedgerow, vegetatio

Field boundary habitats and their contribution to the area of semi-natural habitats on lowland farms in east Galway, western Ireland

peer-reviewedSustainable agriculture and the provision of environmental public goods are key deliverables for European farming and food production. Farmland biodiversity, cultural landscapes, soil functionality and climate stability are among the environmental public goods provided through agriculture. Future Common Agricultural Policy (CAP) direct payments are intended to be more targeted at the provision of these agricultural deliverables. Field boundaries are an example of such deliverables. They are widespread features that have both environmental and aesthetic functions in farmed landscapes. However, research on their variety, density and contribution to semi-natural habitat cover on farms in Ireland is lacking. This study investigates the diversity and density of all field boundary habitat types on 32 lowland farms in east County Galway, western Ireland. A total of 286km of field boundaries were surveyed across six study sites. Five types of field boundary habitats were recorded. The density of field boundaries on the farms studied was high and could have positive implications for delivery of environmental public goods and sustainable farming metrics. In more intensively farmed areas, field boundaries were the only remaining semi-natural habitat on some farms highlighting the need to retain, and improve the ecological quality, of these features. The condition of one field boundary type (hedgerows) was also investigated in further detail. While the density of field boundaries was high on many of the surveyed farms, we found that the hedgerows on these farms were not necessarily in good condition for wildlife

Structural development in Danish agriculture and its implications for farmland nature

During the last decades, development of Danish agriculture was characterised by concentration of land on fewer and larger farms and consequently increasing farm sizes. On basis of three case studies supplemented by national data we explore relationships between farm size change and farmland nature in terms of field sizes and hedgerow densities. Data point to a significant relationship between farm enlargement and increases in mean field sizes. Furthermore, mean field size is negatively related to densities of hedgerows. For the coming decades, scenarios for Danish agriculture point to a continued increase in farm sizes. We argue for an increased focus on the effects of a continued scale enlargement on farmland nature in terms of changes in field size structure. In order to reduce harmful influences of scale enlargement, we suggest that in relation to changes in field structure, agricultural policies should focus on restrictions on removal of old hedgerows and on subsidies for planting of ne

Effects on herbicides on hedgerow biodiversity

Low dosages of herbicides may reduce the number of flowers on non-target plants. Effect of herbicides on flowering and on pollen and nectar production are relevant end-points for effect assessment on non-target species. Herbicides have the potential to reduce the number of flowers in hedgerow vegetation and thereby also decrease the availability of pollen, nectar and seeds that are important food for many insects and birds. The biodiversity of hedgerow bottom vegetation is lower at conventional than at organic farms, presumably as a consequence of the herbicide use

Yield determination in olive hedgerow orchards. II. Analysis of radiation and fruiting profiles

Profiles of fruit density, fruit size, and oil content were measured on 12 occasions in 7 olive orchards in Spain and 2 in Australia. Orchard structure varied widely. Height ranged from 2.0 to 5.5 m, row spacing from 3 to 6 m, and canopy width from 0.7 to 3m. Most orchards were oriented north–south (N–S) but one in Spain was oriented close to east–west (E–W)(208NE–SW). All orchards in Spain were cv. Arbequina, and in Australia they were cvv. Barnea and Picual. Analyses with a model of interception and transmission that estimated interception by individual sides of hedgerows revealed that fruit size and oil content were strongly related to intercepted radiation during the month before harvest across all orchards. Relationships were also evident between fruit density and interception but varied among orchards and years, indicating the importance of other environmental and probably physiological effects. In N–S orchards of cv. Arbequina, average fruit size and oil content increased linearly from 0.40 g (dry weight) to 0.72 g, and from 36 to 49% (of dry weight), as daily intercepted PAR increased from 6 to 25 mol/m2 (15–60% of horizontally incident radiation). The general principles of response extended to E–W orchards. There, it was shown that generally large fruit with high oil content on S sides was consistent with the plateau responses to radiation evident in the more extensive N–S data. On the N side, however, and accounting for transmission through the hedgerow, both fruit size and oil content were greater than in positions intercepting equivalent radiation inN–S orchards. Examples are provided of the utility of responses of fruit density, size, and oil content in establishing combinations of row height, row width, and row distance to improve or maintain productivity in some of the orchards included in the study

How much do we really lose?—Yield losses in the proximity of natural landscape elements in agricultural landscapes

Natural landscape elements (NLEs) in agricultural landscapes contribute to biodiversity and ecosystem services, but are also regarded as an obstacle for large‐scale agricultural production. However, the effects of NLEs on crop yield have rarely been measured. Here, we investigated how different bordering structures, such as agricultural roads, field‐to‐field borders, forests, hedgerows, and kettle holes, influence agricultural yields. We hypothesized that (a) yield values at field borders differ from mid‐field yields and that (b) the extent of this change in yields depends on the bordering structure. We measured winter wheat yields along transects with log‐scaled distances from the border into the agricultural field within two intensively managed agricultural landscapes in Germany (2014 near Göttingen, and 2015–2017 in the Uckermark). We observed a yield loss adjacent to every investigated bordering structure of 11%–38% in comparison with mid‐field yields. However, depending on the bordering structure, this yield loss disappeared at different distances. While the proximity of kettle holes did not affect yields more than neighboring agricultural fields, woody landscape elements had strong effects on winter wheat yields. Notably, 95% of mid‐field yields could already be reached at a distance of 11.3 m from a kettle hole and at a distance of 17.8 m from hedgerows as well as forest borders. Our findings suggest that yield losses are especially relevant directly adjacent to woody landscape elements, but not adjacent to in‐field water bodies. This highlights the potential to simultaneously counteract yield losses close to the field border and enhance biodiversity by combining different NLEs in agricultural landscapes such as creating strips of extensive grassland vegetation between woody landscape elements and agricultural fields. In conclusion, our results can be used to quantify ecocompensations to find optimal solutions for the delivery of productive and regulative ecosystem services in heterogeneous agricultural landscapes

Hedgerows as form of agroforestry to sequester and store carbon in agricultural landscapes: a review

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Opportunities and Obstacles in Adoption of Biodiversity-Enhancing Features on California Farms

The USDA National Organic Program requires the conservation of biodiversity and the maintenance or improvement of natural resources on organic farms. On-farm biodiversity-enhancing features such as border plantings can provide many of these ecosystem services. However, which practices farmers currently use to manage non-cropped edges, why and how they use these practices, and how subsidies and technical assistance affect farmers’ ability and willingness to manage farm edges for biodiversity are little studied topics. Our study set out to identify the range of practices currently used to manage non-cropped field edges, roadsides, pond edges, and banks of permanent watercourses (sloughs, canals, ditches) in a case study area in California. Secondary objectives were to gauge local farmers’ awareness of planted hedgerows and vegetated waterways and to gather preliminary information about the range of incentives and constraints to installing such features