Plant Diversity Research Articles

Fossil pollen data can reconstruct robust spatial patterns of biodiversity in the past

Fossil pollen data are valuable for understanding past spatio-temporal variations in plant diversity. However, deducing robust patterns of fossil pollen-assemblage properties is challenging due to factors related to pollen production, dispersal, and fossilisation; sediment sampling; and nomenclature and taxonomy of the fossil pollen grains reflecting the vegetation that produced them. If the composition pattern of the most recent fossil pollen assemblage concords with those in modern or surface pollen assemblages from the same location(s), the pattern can be regarded as robust.Using recent (50–500 years) fossil pollen and surface pollen assemblages of angiosperms compiled from the same geographic area of Central Asia, we analyse spatial patterns in compositional turnover and phylogenetic dispersion. These are widely used to quantify different aspects of plant diversity.Despite differences in the data regarding spatial coverage, number of pollen records, and number of pollen taxa, the spatial pattern in the modern and fossil pollen-assemblage properties across climate zones is broadly similar. Especially, the latitudinal patterns of pollen-assemblage properties are strikingly similar between both data types. However, the degree of concordance varies according to the diversity metric being analysed, and the magnitudes of the metric may differ between both data types. When the data are compiled, processed, and standardised following consistent criteria and analysed using appropriate metrics and methods, spatial patterns in pollen-assemblage properties of fossil pollen data are as robust as those in surface pollen data (∼modern vegetation). Therefore, regional patterns of compositional turnover and phylogenetic dispersion can be confidently inferred from older fossil assemblages through the Holocene.

Species interactions amplify functional group responses to elevated CO2 and N enrichment in a 24-year grassland experiment.

Plant functional groups (FGs) differ in their response to global changes, although species within those groups also vary in such responses. Both species and FG responses to global change are likely influenced by species interactions such as inter-specific competition and facilitation, which are prevalent in species mixtures but not monocultures. As most studies focus on responses of plants growing in either monocultures or mixtures, but rarely both, it remains unclear how interspecific interactions in diverse ecological communities, especially among species in different FGs, modify FG responses to global changes. To address these issues, we leveraged data from a 16-species, 24-year perennial grassland experiment to examine plant FG biomass responses to atmospheric CO2, and N inputs at different planted diversity. FGs differed in their responses to N and CO2 treatments in monocultures. Such differences were amplified in mixtures, where N enrichment strongly increased C3 grass success at ambient CO2 and C4 grass success at elevated CO2. Legumes declined with N enrichment in mixtures at both CO2 levels and increased with elevated CO2 in the initial years of the experiment. Our results suggest that previous studies that considered responses to global changes in monocultures may underestimate biomass changes in diverse communities where interspecific interactions can amplify responses. Such effects of interspecific interactions on responses of FGs to global change may impact community composition over time and consequently influence ecosystem functions.

A systematic review exploring the diversity and food security potential of wild edible plants in Ethiopia

Wild edible plants (WEPs) are important food sources globally due to their accessibility and affordability. In Ethiopia, where diverse cultural groups consume WEPs, this systematic review explores their diversity, edible parts, and role in supporting food security. The review examined 38 original studies on the ethnobotany of WEPs in Ethiopia from 2000 to 2022. It identified a total of 651 WEP species from 343 genera and 94 families, with the Fabaceae family having the most species (51). Herbs and shrubs were the predominant growth habits, and fruits were the most consumed plant parts. The review prioritized nine WEP species for cultivation and promotion. However, threats such as overgrazing, agricultural expansion, and the use of woody species for construction, firewood, and charcoal have depleted WEP resources and eroded traditional knowledge about their use. The review suggests that WEPs have the potential to contribute to food and nutritional security in Ethiopia if these threats are effectively managed. However, the limited coverage of ethnobotanical studies on WEPs requires further investigation. The study recommends integrating the prioritized WEPs into the national food system for promotion, cultivation, and nutrient analysis to evaluate their nutritional bioavailability.

Detecting Vegetation Stress in Mixed Forest Ecosystems Through the Joint Use of Tree‐Water Monitoring and Land Surface Modeling

AbstractRecent European heatwaves have significantly impacted forest ecosystems, leading to increased plant water stress. Advances in land surface models aim to improve the representation of vegetation drought responses by incorporating plant hydraulics into the plant functional type (PFT) classification system. However, reliance on PFTs may inadequately capture the diverse plant hydraulic traits (PHTs), potentially biasing transpiration and vegetation water stress representations. The detection of vegetation drought stress is further complicated by the mixing of different tree species and forest patches. This study uses the Community Land Model version 5.0 to simulate an experimental mixed‐forest catchment with configurations representing standalone, patched mixed, and fully‐mixed forests. Biome‐generic, PFT‐specific, or species‐specific PHTs are employed. Results emphasize the crucial role of accurately representing mixed forests in reproducing observed vegetation water stress and transpiration fluxes for both broadleaf and needleleaf tree species. The dominant vegetation fraction is a key determinant, influencing aggregated vegetation response patterns. Segregation level in PHT parameterizations shapes differences between observed and simulated transpiration fluxes. Simulated root water potential emerges as a potential metric for detecting vegetation stress periods. However, the model's plant hydraulic system has limitations in reproducing the long‐term effects of extreme weather events on needleleaf tree species. These findings highlight the complexity of modeling mixed forests and underscore the need for improved representation of plant diversity in land surface models to enhance the understanding of vegetation water stress under changing climate conditions.

Doubling down on polyploid discoveries: Global advances in genomics and ecological impacts of polyploidy.

All flowering plants are now recognized as diploidized paleopolyploids (Jiao et al., 2011; One Thousand Plant Transcriptomes Initiative, 2019), and polyploid species comprise approximately 30% of contemporary plant species (Wood et al., 2009; Barker et al., 2016a). A major implication of these discoveries is that, to appreciate the evolution of plant diversity, we need to understand the fundamental biology of polyploids and diploidization. This need is broadly recognized by our community as there is a continued, growing interest in polyploidy as a research topic. Over the past 25 years, the sequencing and analysis of plant genomes has revolutionized our understanding of the importance of polyploid speciation to the evolution of land plants.

Honey bees and mason bees as biological indicators of landscape pesticide loads: Different results but similar conclusions

Agricultural environments, including crop and non-crop areas, often provide important pollen and nectar resources for managed and wild bees. However, these resources may be contaminated with pesticides detrimental to bees and other non-target organisms, including humans. Differences in life-history traits among bee species influence food resource exploitation and pesticide exposure. This study assesses the potential of honey bees (Apis mellifera) and mason bees (Osmia), two bee species with highly contrasting functional traits, as biological indicators of pesticide exposure in 34 Italian agricultural farms. Pollen loads of both species were used to identify pollen species collected and to analyse multi-residue levels of pesticides. Pesticide risk indexes were calculated for honey bees, mason bees and humans. In mason bees, pesticide risk was not influenced by plant diversity. In agreement with their pollen preferences and short foraging ranges, mason bees collected a high proportion of pollen from flowers of the target crop. Conversely, pesticide risk decreased with increasing pollen diversity in honey bees. In agreement with their generalist foraging habits and long foraging ranges honey bees collected a greater diversity of pollen species and a lower proportion of target crop pollen. Although honey bees and mason bees showed similar toxic loads and pesticide composition, at a field scale pesticide risk of one species is not a good indicator of the risk to the other species. Our study confirms that bees in agricultural environments are pervasively exposed to multi-residue pesticide loads. Exposure is conditioned by specific bee traits but is also highly context-dependent.

IDENTIFICATION OF MOSS PLANTS AROUND NAMORAMBE DISTRICT

Non-vascular plants, such as mosses (Bryophyta), are commonly found on land. The class of plants known as tuberous plants, or plants that do not have true roots, stems, or leaves as well as xylem and phloem vessels, includes moss plants. Knowing the diversity of moss plants in Namorambe Sub-district is the purpose of this research. On May 9, 2024, this research was conducted by walking around the Namorambe area to look for moss plants that might be there. This research methodology is qualitative, using descriptive and exploratory techniques. This research used observation, documentation, and literature study as data collection methods. Direct investigation into the Namorambe area was used to make observations to identify moss plants. The three species identified based on the results of the identification of leaf mosses around Namorambe Sub-district were Hyophila sp., Pogonatum cirrhatum, and Barbula indica. Leaf mosses were made near people's work areas and were made on tree bark and stone substrates

Characteristics of urban milkweed gardens that influence monarch butterfly egg abundance

The eastern population of monarch butterflies (Danaus plexippus) has dramatically declined in the last few decades, which is largely attributed to a loss of milkweed habitat in agricultural areas. Residential land in metropolitan areas has the potential to provide a significant source of the milkweed needed to support the monarch population. To examine if and how urban milkweed patches can support monarch butterflies, we worked with community scientists in the Chicago metropolitan area to monitor monarch eggs and caterpillars in yards and community gardens. We hypothesized that the largest numbers of eggs (i.e. gardens that were most attractive to monarchs) would be observed in patches that were older, had a high abundance of milkweed, contained more than one species of milkweed including Asclepias syriaca (common milkweed) and/or A. incarnata (swamp milkweed), and had a large diversity of nectar plants. All patches were assessed at their peak egg count each year, which ranged from zero to 170 eggs in a given observation. To determine which characteristics were most influential to egg presence, we examined patches where eggs were present or absent during this peak observation. For abundance, we divided these peak observations into whether or not the egg counts were in the top 20% in a given year, excluding patches where eggs were absent, and assessed their patch characteristics. Our results show that patch age and presence of A. syriaca affected whether patches contained eggs or not. We also found that patches with the largest number of eggs observed tended to have A. syriaca, more milkweed plants, and a higher diversity of blooming plant species. The data we collected from community scientists in the Chicago area has enhanced our understanding of how urban gardeners can create effective breeding habitats for monarch butterflies. By planting Asclepias syriaca within its natural range, along with other native milkweed species and a diverse selection of flowering plants, individuals can create gardens that serve as excellent habitats for monarchs and other pollinators.

Exploring traditional cosmetic flora from Comoros islands: An ethnobotanical survey in Mayotte

Mayotte is located in the Indian Ocean and is home to more than five languages, cultures and lifestyles. However, due to rapid urbanization, this traditional knowledge is at risk of extinction. Moreover, ethnobotanical studies on the pharmacopoeia and cosmetopoeia in Mayotte are almost nonexistent. This study was carried out to document the traditional knowledge of Mayotte's cosmetopoeia. The main objective of this study was to document the diversity of cosmetic plants used by the Mahoran community. We conducted field surveys from 2021 to 2022 in 14 communes of “Grande Terre”, the largest of the two islands from Mayotte. A total of 35 experts (fundi) were interviewed in this study. Individual interviews with Mahoran informants using open questions were conducted, and voucher specimens were collected for each plant species cited. A total of 470 cosmetic formulations, representing a total of 1777 URs, were recorded. Each formulation contains 1 to 13 ingredients, with a predominance of single-ingredient recipes. In particular, hygiene, makeup, fragrance, hair and nails, and dermatology are the most cited cosmetic categories. A total of 83 plant species were identified and the five most cited plant species were, in decreasing order: Cocos nucifera (273 URs), Jasminum nummulariifolium (191 URs), Ocimum spp. (120 URs), Curcuma longa (105 URs), and Lawsonia inermis (101 URs). This study is one of the first to focus solely on the exploration of cosmetopoeia in Mayotte, contributing to the preservation of knowledge and the promotion of customs related to traditional cosmetics on this island. Further studies should be performed on some highly cited plant species endemic to the area (e.g., Jasminum nummulariifolium, Pandanus maximus) to confirm their interest for the cosmetic industry and thus contribute to the economic growth of Mahoran people.

Reintroduction strategies for rare arable weeds in agricultural practice and their influence on yield

AbstractAgricultural intensification and changing landscape structure led to decreasing numbers of arable flora and fauna during the last decades. To counteract these declines, arable plant diversity needs to be restored. It is important to promote regional plant communities including endangered species to ensure adaption to agricultural landscapes. Therefore, this study examines the development of arable plant diversity, crop yield and the reintroduction success of rare arable plants (RAPs) under different practical farming strategies in cereals from 2019 to 2021 in southwestern Germany. Farming strategies varied regarding weed control intensity (none, mechanical, herbicide with and without efficiency gap), fertilisation (mineral and none) and row spacing (12.5 cm and 20 cm). Additionally, two different seed mixtures containing RAP and common species were used for reintroduction: one commercially available and another self‐composed. Reintroduction success was quite high with more than 80% establishment rate. Species numbers doubled in all treatments over time, except the one with herbicide application, with on average 8–10 species emerging from the soil seed bank. Reintroduction of RAP increased arable plant species richness further up to 37 species. The site‐adapted mixture showed in the end a site‐typical weed community. Yield was significantly lower in treatments with reintroduction via sown mixtures and no weed control, losing on average 65% yield. The reintroduction of RAP was successful and accompanied by an increasing floral diversity, however, with a simultaneous yield loss. Financial incentives or subsidies are therefore still necessary to compensate yield loss for reintroduction and conservation efforts.

Reviewing the Optimal Conditions for Efficiently Harnessing the Phytotherapeutic Potential of the Invasive Carpobrotus edulis (L.) N.E. Br Plant Threatening Plant Diversity

Within the scope of this study, the study conducted by Pereira et al. on the examination of the plant species Carpobrotus edulis (L.) N.E.Br, known as Hottentot-fig, is examined. This plant poses a great threat to biodiversity in coastal areas with its invasive feature. Pereira and his colleagues aimed to reveal the phytotherapeutic potential of the Hottentot-fig plant to turn this crisis situation into an opportunity. By evaluating the bioactive components and antioxidant and anti-inflammatory properties of the plant, which vary depending on harvest time and location, the usability of this plant in the food and nutraceutical industries has been demonstrated. In the methodology and results of this valuable study conducted by Pereira et al., methods such as extraction and total phenolic content HPLC-DAD were compared with other literature studies in order to determine the optimum parameters. By comparing the results of the study on Hottentot-fig, the shortcomings and strengths of the study were determined. Within the scope of our study, it is stated that alternative methods should be taken into consideration in addition to the known methods used in the literature, the results of these methods should be examined, and efficient results can be obtained with different method strategies.

Depth-dependent responses of soil bacterial communities to salinity in an arid region

Soil salinization adversely affects soil fertility and plant growth in arid region worldwide. However, as the drivers of nutrient cycling, the response of microbial communities to soil salinization is poorly understood. This study characterized bacterial communities in different soil layers along a natural salinity gradient in the Karayulgun River Basin, located northwest of the Taklimakan desert in China, using the 16S rRNA Miseq-sequencing technique. The results revealed a significant filtering effect of salinity on the bacterial community in the topsoil. Only the α-diversity (Shannon index) in the topsoil (0–10 cm) significantly decreased with increasing salinity levels, and community dissimilarity in the topsoil was enhanced with increasing salinity, while there was no significant relationship in the subsoil. BugBase predictions revealed that aerobic, facultatively anaerobic, gram-positive, and stress-tolerant bacterial phenotypes in the topsoil was negatively related to salinity. The average degree and number of modules of the bacterial co-occurrence network in the topsoil were lower under higher salinity levels, which contrasted with the trends in the subsoil, suggesting an unstable bacterial network in the topsoil caused by higher salinity. The average path length among bacterial species increased in both soil layers under high salinity conditions. Plant diversity and available nitrogen were the main drivers affecting community composition in the topsoil, while available potassium largely shaped community composition in the subsoil. This study provides solid evidence that bacterial communities adapt to salinity through the adjustment of microbial composition based on soil depth. This information will contribute to the sustainable management of drylands and improved predictions and responses to changes in ecosystems caused by climate change.

Expowo: An R package for mining global plant diversity and distribution data

AbstractPremiseData on plant distribution and diversity from natural history collections and taxonomic databases are increasingly becoming available online as exemplified by the Royal Botanic Gardens, Kew's Plants of the World Online (POWO) database. This growing accumulation of biodiversity information requires an advance in bioinformatic tools for accessing and processing the massive data for use in downstream science. We present herein expowo, an open‐source package that facilitates extracting and using botanical data from POWO.Methods and ResultsThe expowo package is implemented in R and designed to handle the entire vascular plant tree of life. It includes functions to readily distill taxonomic and distributional information about all families, genera, or species of vascular plants. It outputs a complete list of species in each genus of any plant family, with the associated original publication, synonyms, and distribution, and plots global maps of species richness at the country and botanical country levels, as well as graphs displaying species‐discovery accumulation curves and nomenclatural changes over time. To demonstrate expowo's strengths in producing easy‐to‐handle outputs, we also show empirical examples from a set of biodiverse countries and representative species‐rich and ecologically important angiosperm families.ConclusionsBy harnessing bioinformatic tools that accommodate varying levels of R programming proficiency, expowo functions assist users who have limited R programming expertise in efficiently distilling specific botanical information from online sources and producing maps and graphics for the further interpretation of biogeographic and taxonomic patterns.

Synchronised monitoring of plant and insect diversity: a case study using automated Malaise traps and DNA-based methods.

The occurrence and distribution of insects and their possible associations with plant species are largely unknown in Germany and baseline data to monitor future trends are urgently needed. Using newly-designed automated Malaise trap multi-samplers, the occurrence of insect species and their potential associations with plants was monitored synchronously at two contrasting field sites in Germany: an urban botanical garden and a forest research station. Taxa were identified by metabarcoding of the insects and the plant traces present in the preservative ethanol of the Malaise trap samples. For comparison, a botanical survey was conducted in the vicinity of the traps. Across both sites, we identified a total of 1290 exact sequence variants (ESVs) assigned to Insecta, of which 205 are known to be pollinators. In the botanical garden, we detected the occurrence of 128 plant taxa, of which 41 also had one of their known insect pollinator species detected. Insect species richness was highest in May, mainly attributed to an increase in Diptera. These results present a case study of the applicability of automated sampling and DNA-based methods to monitor the timings of flowering and corresponding activity of plant-visiting insects.

Ethnobotanical study of medicinal plants among the Karo Tribe in Kuala Sub-district, Langkat District, North Sumatra, Indonesia

Abstract. Gani ARF, Hastuti US, Sulisetijono S, Setiowati FK. 2024. Ethnobotanical study of medicinal plants among the Karo tribe in Kuala Sub-district, Langkat District, Indonesia. Biodiversitas 25: 2960-2968. Indonesia has a high diversity of plants. One area of Indonesia with a high diversity of plants is Kuala Sub-district, Langkat District, North Sumatra Province, Indonesia. The Karo tribe inhabits Kuala Sub-district, and they still apply the ethnomedicine knowledge in their life; this study aims to: (i) document ethnomedicine knowledge of the use of medicinal plants in Kuala Sub-district, (ii) Analyze the use value and cultural significance index to determine the level of use of medicinal plants by the Karo people in Kuala Sub-district. Ethnomedicine data were collected for eleven months, from October 2022 to April 2024. The data sources in this research were 205 informants (25 key informants and 180 additional informants). Data from 25 key informants was used to determine the cultural significance index, while data from 180 additional informants was used to determine use value (UV). ICS data was collected by conducting focus group discussions with key informants, while UV data collection was carried out using survey techniques. The research was conducted through semi-structured interviews to determine various medicinal plants' quality, intensity, and exclusivity. This research shows 49 plants used in medicinal practice, and the highest significant cultural index and use value is Kaempferia galanga. The part of the plant that is most widely used is the leaf. The most common disease experienced by the Karo people in Kuala Sub-district is flatulence and many medicinal plants are used to treat this disease.

Documentation On Medicinal Plants of Khanapur Forest Bidar District, Karnataka

The present study was undertaken to document medicinal plants of Khanapur forest Bidar district, karnataka the documentation of medicinal plants helps to recognize the overall ecological conditions and gives profound understanding of the economic medicinal and traditional importance of medicinal plants diversity. The present research documentation work was started in November 2023 and completed in February 2024. The present study reported that 119 Medicinal plant species belongs to 54 families distributed in Khanapur forest Bidar included angiosperms Pteridophytes and Gymnosperms. Abrus precatorius, Ephedra, Withania sominifera, Catharanthus roseus, Tinospora cardifolia, Andrographis paniculata, Phyllanthus amarus, allium sativum, Cocos nucifera, Coleus aromaticus, Curcuma longa, Martynia annua, Ocimum tenuiflorum, Tamarindus indica, Terminalia chebula,Tithonia diversifolia, Acalypha indica, Brassica juncea, Clitoria ternatea, Datura metal, Delonix elata, Euphorbia antiquorum, Luffa acutangula, Madhuca longifolia, Myristica fragrans, Santalum album and Vitex negundo are some of the important medicinal plants of Khanapur forest Bidar district of karnataka.

Performance and yield stability of cayenne peppers (Capsicum frutescens) in multilocation trials in the Indonesian lowlands

Abstract. Sayekti TWDA, Syukur M, Hidayat SH, Maharijaya A, Sobir, Agustina K, Mareza E, Wahyudi A, Supriyanta B. 2024. Performance and yield stability of cayenne peppers (Capsicum frutescens) in multilocation trials in the Indonesian lowlands. Biodiversitas 25: 3008-3017. Cayenne pepper (Capsicum frutescens L.) plant breeding is becoming an increasingly interesting topic due to various usages. The diversity of uses of chilies needs to be balanced with high production and good product quality so that it can meet market needs. This experiment aimed to evaluate the performance and plant diversity of eight elite lines and six commercial varieties of cayenne pepper (C. frutescens) in three different environments. The development of location-specific superior genotypes can be guided to create varieties suited to the targeted environment. This study was conducted in three locations (environments) namely “Lampung”, “Yogyakarta” and “Palembang”. The experiment was conducted using a Randomized Complete Block Design (RCBD) with three replications for each location. Analysis of yield stability was conducted using three methods, namely “Francis-Kanneberg”, “Finlay-Wilkinson” and “AMMI” methods. Among the three locations, the Lampung location experienced a very significant yield loss. This is thought to be due to disease attacks on the plantations. Some genotypes are more suitable for planting at one of the test locations compared to the other two locations. However, there are two genotypes that are stable at three locations based on the three analysis methods used. Genotypes "F1.323340" and "F1.285290” were observed to be stable and produced well at all test locations. Both genotypes can be recommended for planting in lowland environment.

Soil Fungal Pathogens in Pinus pinaster Mature Reforestation: Silvicultural Treatments Effects.

Soil fungal communities play a key role in multiple functions and ecosystem services within forest ecosystems. Today, forest ecosystems are subject to multiple environmental and anthropogenic disturbances (e.g., fire or forest management) that mainly lead to changes in vegetation as well as in plant-soil interactions. Soil pathogens play an important role in controlling plant diversity, ecosystem functions, and human and animal health. In this work we analyzed the response of soil plant pathogenic fungi to forest management in a Pinus pinaster reforestation. We started from an experimental design, in which forest thinning and gap cutting treatments were applied at different intensities and sizes, respectively. The fungal communities of plant pathogens in spring were described, and the effect of the silvicultural treatments was evaluated 5 years after their application, as were the possible relationships between soil plant pathogenic fungal communities and other environmental factors. Only a strong low thinning treatment (35% basal area) was able to generate homogeneous changes in soil pathogenic diversity. In the gaps, only the central position showed significant changes in the soil plant pathogenic fungi community.

Scale dependency of taxonomic and functional diversity in pristine and recovered loess steppic grasslands

Widespread campaigns on forest restoration and various tree planting actions lower the awareness of the importance of grasslands for carbon sequestration and biodiversity conservation. Even lower attention is given to the conservation of biodiversity and ecosystem functioning in remnants of ancient, so-called pristine grasslands. Pristine grasslands generally harbour high biodiversity, and even small patches can act as important refuges for many plant and animal species in urbanised or agricultural landscapes. Spontaneous succession of grassland is frequently viewed as a cost-effective tool for grassland restoration, but its applicability is strongly dependent on many local to landscape-scale factors, and the recovery is often slow. It is therefore essential to monitor the success of grassland restoration projects that rely on spontaneous succession. We compared the species diversity and functional attributes of pristine and recovered grasslands by studying the taxonomic and functional diversity in thirteen (8 pristine and 5 recovered) loess steppic grasslands using differently sized sampling plots from 0.01 to 100 m2. Our results indicate that there are remarkable differences in taxonomic and functional diversity between pristine and recovered grasslands. We also found that during secondary succession there is a likely functional saturation of the species assembly in the first few decades of recovery, and while patterns and structure of recovered grasslands became quite similar to those of pristine grasslands, species richness and diversity still remained much lower. Pristine grasslands support considerable plant diversity, and species composition is slow to recover if destroyed by agricultural land use. This underlines the importance of preserving existing pristine grassland remnants, which might serve as sources of species for future restoration measures.

Close to the edge: Spatial variation in plant diversity, biomass and floral resources in conventional and agri‐environment cereal fields

Abstract Non‐crop (segetal) plants in arable systems are commonly perceived simply as ‘weeds’, that is, harmful at worst and undesirable at best. The increase in management intensity in European arable systems has vastly reduced the populations of all but the most disturbance‐tolerant plant species, negatively impacting the whole agricultural food web. In recent years, efforts have been made to promote agricultural biodiversity through measures such as flower strips and unsprayed field margins. However, studies of their impacts on the arable flora have rarely considered their spatial variation within the crop field. We investigated the spatial distribution of vascular plant species richness and their contribution to the food web via biomass and flower units in conventional and agri‐environment cereal fields in six regions of Germany. We studied two types of in‐crop measures (extensive cereals without pesticides or fertiliser, and with or without intercropping with flowering species) and one adjacent measure (neighbouring flower strip), recording at 1‐m intervals from the field edge to the interior. These results were then extrapolated to illustrate the effects of these measures on resource provision at the field scale. Species richness and plant biomass dropped off sharply after the first metre in the conventional treatments, regardless of the adjacent habitat. The ‘extensive’ treatments maintained a much higher level of diversity and resource provision in the field interior. At the field level, this can mean more than a 60‐fold difference in the provision of flowering resources between conventional management (1900 flower units/ha) and agri‐environment measures (AEMs) (127,000 units/ha for extensive cereals). Synthesis and applications. The strong edge effects we found in conventional cultivation support the premise that reducing field sizes could play a role in promoting in‐crop biodiversity. However, incorporating extensive field margins as an AEM would be more efficient at maximising the diversity of generalists whilst maintaining high yields.