Progress 10/01/17 to 09/30/18
Outputs
Target Audience:Ecologists Agroecologists General public Students Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Provided opportunities for 4 early career researchers (Assistant Professors or Researcher at USGS, of which 3 female) to publish or give talks How have the results been disseminated to communities of interest?Publications, talks, blog What do you plan to do during the next reporting period to accomplish the goals?Goal 1 Will be reported underCA-B-INS-0169-H: not repeated here Goal 2. Continue analyses and publications. Two additional publications are being prepared currently. Additional analyses, including genetic analysis of existing specimen data, are being planned. Goal 3. Continue syntheses and publications. One manuscript is partially prepared. Several other synthetic analyses are being planned with other collaborators. Several workshops are planned to realize these collaborations.
Impacts
What was accomplished under these goals?
Goal 1. Will be reported in detail CA-B-INS-0169-H Goal 2. Reported by sub-question 1.How hedgerows, both locally and in the surrounding landscape, influence pollinator communities (occupancy and beta-diversity) : In revision at Ecology Letters. Disconnected habitat fragments are poor at supporting population and community persistence; restoration ecologists therefore advocate for the establishment of habitat networks across landscapes. Few empirical studies, however, have considered how networks of restored habitat patches affect metacommunity dynamics. Here, using a 10-year study on restored hedgerows and unrestored field margins within an intensive agricultural landscape, we integrate occupancy modeling with network theory to examine the interaction between local and landscape characteristics, habitat selection and dispersal in shaping pollinator metacommunity dynamics. We show that surrounding hedgerows and remnant habitat patches interact with the local floral diversity, bee diet breadth and bee body size to influence site occupancy, via colonization and persistence dynamics. Florally-diverse sites and generalist, small-bodied species are most important for maintaining metacommunity connectivity. By providing the first in-depth assessment of how a network of restored habitat influences long-term population dynamics, we confirm the conservation benefit of hedgerows for pollinator populations and demonstrate the importance of restoring and maintaining habitat networks within an inhospitable matrix. 2. How long does it take to restore pollinator communities and their functional properties? Published inFrontiers in Ecology and Evolution, Intensive agriculture reduces wild pollinator abundance, diversity and pollination services, while depending critically on wild pollinators for crop pollination. Floral enhancements such as hedgerows (native, perennial flowering trees and shrubs) can enhance pollinator colonization, persistence, occupancy, and species richness within intensive agricultural landscapes. However, little is known about the specific features of hedgerows that promote pollinator communities in such landscapes. Understanding how pollinator communities respond to local changes in site conditions as hedgerows mature, such as the availability of floral or nesting resources, can help guide the design of more effective hedgerows that promote pollinators and/or pollination services. In an intensively-managed agricultural region of California, we found that pollinator community attributes responded principally to the enhancement of floral diversity as hedgerows mature, as well as to surrounding natural habitat. Once hedgerows matured, this relationship leveled off, suggesting either saturation of community assembly processes, or greater importance of floral density/display relative to diversity. Although we did not find any relationships between measures of pollinator community diversity and nesting resources, such resources are notably difficult to measure. Surrounding natural habitat also affected species and functional richness at hedgerows, particularly for solitary bees that nest above ground. Such species are known to be particularly sensitive to the negative effects of agriculture. Thus, hedgerows in combination with natural habitat may reverse some of the community disassembly provoked by intensive agriculture. 4. Do hedgerows deliver not only pollen and nectar to foraging native pollinators, but also neonicotinoid pesticides? M.L. Hladik, L.T. Ward, C. Kremen, N.J. Mills, Talk given at American Chemical Society 2018 Measuring multiple matrices to determine wild bee exposure to pesticides in an intensively managed agricultural landscape To better understand the exposure of wild bees to pesticides in an agricultural landscape, samples were collected from fields in northern California. Hedgerows are known to provide habitat for wild bees, but these bees may also be exposed to pesticides from nearby agricultural fields. The current study targeted eight hedgerow sites located in an intensively managed agricultural landscape that includes almonds, (wine) grapes, rice, tomatoes, and walnuts. In addition to collecting both wild bees and honeybees, soil, flowers, and silicone passive sampling devices (PSD; staked near the hedgerows to sample the air) were also included. Sampling was conducted from April to June, 2016, to coincide with peak bloom and bee activity for comparison with pesticide use records from the surrounding landscape. Samples were analyzed for >150 pesticides and degradates using similar extraction clean-up steps for the various matrices and analysis with both gas and liquid chromatography-tandem mass spectrometry. Overall, 38 pesticides were detected in all matrices (10 insecticides and degradates, 12 fungicides, 15 herbicides and degradates, and 1 plant growth regulator). The number and type of pesticides detected varied by matrix; 24 compounds were detected in the PSDs, 24 in soil, 15 in flowers, 18 in native bees, and 10 in honeybees. These results can help determine which matrices are best at estimating wild bee pesticide exposure and which pesticides should be targeted for future effects work. Goal 3. We published 4 synthetic papers. C. Kremen, & Merenlender, A. M. (2018). Science How can we manage farmlands, forests, and rangelands to respond to the triple challenge of the Anthropocene--biodiversity loss, climate change, and unsustainable land use? When managed by using biodiversity-based techniques such as agroforestry, silvopasture, diversified farming, and ecosystem-based forest management, these socioeconomic systems can help maintain biodiversity and provide habitat connectivity, thereby complementing protected areas and providing greater resilience to climate change. Simultaneously, the use of these management techniques can improve yields and profitability more sustainably, enhancing livelihoods and food security. This approach to "working lands conservation" can create landscapes that work for nature and people. However, many socioeconomic challenges impede the uptake of biodiversity-based land management practices. Although improving voluntary incentives, market instruments, environmental regulations, and governance is essential to support working lands conservation, it is community action, social movements, and broad coalitions among citizens, businesses, nonprofits, and government agencies that have the power to transform how we manage land and protect the environment. C.Kremen, M. Albrecht and L.Ponisio. Book Chapter. Native wild pollinators are as important as managed honeybees for the production of pollinator-dependent crops. However, the demand for pollination services in intensively managed agricultural lands often outstrips the supply. Re-diversifying agricultural lands through hedgerow plantings could help to promote native pollinators and deliver pollination services into adjacent fields. This review assesses whether hedgerows support native pollinator populations and export pollination services to crops or concentrate existing pollinators in the landscape, thereby competing with crops. Existing evidence based on a suite of indicators (resource, temporal, spatial, and functional) largely supports the exporter hypothesis, but many research gaps exist. Substantial evidence exists showing that hedgerows provide floral resources across the season and that pollinator communities track this resource, but few studies of nesting resources exist. Studies from one region show that pollinator population dynamics are enhanced by hedgerows across years, leading to enhanced alpha, beta, and functional diversity. The few studies on pollination services are positive or neutral. Ramankutty et al 2018 and Carlson et al. 2018 reported in Publications.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
C. Kremen, & Merenlender, A. M. (2018). Landscapes that work for biodiversity and people. Science, 362(6412), eaau6020. DOI:10.1126/science.aau6020
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
C. Kremen, MGonigle, L. K., & Ponisio, L. C. (2018). Pollinator Community Assembly Tracks Changes in Floral Resources as Restored Hedgerows Mature in Agricultural Landscapes. Frontiers in Ecology and Evolution, 6(October), 110. DOI:10.3389/fevo.2018.00170
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Ramankutty, N., Mehrabi, Z., Waha, K., Jarvis, L., C. Kremen, Herrero, M. & Rieseberg, L.H. (2018) Trends in Global Agricultural Land Use: Implications for Environmental Health and Food Security. Annual Review of Plant Biology, 69.
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
C. Kremen (2018) The value of pollinator species diversity. Science, 359, 741742. DOI:10.1126/SCIENCE.AAR7614
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Henselek, Y., Eilers, E.J., C. Kremen, Hendrix, S.D. & Klein, A.M. (2018) Pollination Requirements of Almond (Prunus dulcis): Combining Laboratory and Field Experiments. Journal of Economic Entomology, 111, 1006-1013.
- Type:
Book Chapters
Status:
Awaiting Publication
Year Published:
2019
Citation:
RESTORING POLLINATOR COMMUNITIES AND POLLINATION SERVICES IN HEDGEROWS IN INTENSIVELY MANAGED AGRICULTURAL LANDSCAPES
Claire Kremen, Matthias Albrecht and Lauren Ponisio
Chapter 9, in Hedgerows and Field Margins, edited by John Dover.
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Carlson, K.M., Heilmayr, R., Gibbs, H.K., Noojipady, P., Burns, D.N., Morton, D.C., Walker, N.F., Paoli, G.D. & C. Kremen (2017) Effect of oil palm sustainability certification on deforestation and fire in Indonesia. PNAS, 115, 121-126. DOI: 10.1073/pnas.1704728114
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Progress 10/01/16 to 09/30/17
Outputs
Target Audience:University community Farmers General public, including children Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Three graduate students participated in this work, 1 post-doc and 11 undergraduates (not including the personnel involved in Goal 1, which is reported underCA-B-INS-0169-H.) How have the results been disseminated to communities of interest?Again, we do not report on Dissemination for Goal 1, which is thoroughly documentedunderCA-B-INS-0169-H. 1. Publications (see Products) 2. Blogs and Outreach documents (see Other Products) 3. Communications (listed below): Public outreach lectures and events 2017: Arts and Ecology Panel, Pro Arts Gallery, Oakland California Academy of Sciences, educational video for Flipside Science series CalScience panel discussion on science communications and food, UC Berkeley, Berkeley Ca Kids for the Bay Summer Camp,Berkeley Ca Sees the Day Summer Camp,Berkeley Ca 2016: UC Davis Beekeeper conference, Davis, CA San Mateo Beekeeping Association, San Mateo, CA Mt. Diablo Beekeeper Association Marin County Beekeeper Association Women in Science Lecture, Field Museum, Chicago, Illinois, Nov Earth Day at the Gill Tract Community Farm, Berkeley, CA Farming for Beneficials, Xerces Society/General Mills Grass Up, Organic Valley, Oakland, CA Kids for the Bay Summer Camp, Berkeley, CA Sees the Day Summer Camp, Berkeley, CA 2017 Iowa State University departmental seminar, Ames, Iowa IRES seminar, University of British Columbia, Vancouver, BC, Canada American Association for the Advancement of Science, Symposium Speaker, Boston, MA P.T. Barnum Annual Lecture, Dept of Biology, Tufts University, Somerville, MA Bay Area Conservation Biology Society Symposium, Santa Cruz, CA(2 talks) Expand your horizons Conference, UC Berkeley, Berkeley, CA 2016 Yale Institute for Biospheric Studies, Yale University, New Haven, CT US Regional Association of the International Association for Landscape Ecology, Asheville, NC Bay Area Conservation Biology Society Sympoisum, Stanford, CA Participants: Claire Kremen (Faculty Member); Lauren Ponisio (Postdoc); Emily Kearney (Graduate student), Aidee Guzman (Graduate Student) What do you plan to do during the next reporting period to accomplish the goals?Goal 1. SeeCA-B-INS-0169-H. In addition, supervise student that is separately investigating how crop diversification affects arbuscular mycorrhizal fungi, pollinators, and their below - to - above ground interactions (via the affect of AMF on crop pollen and nectar). Goal 2. 1. Continue work on 3 manuscripts in preparation and submit for publication. 2. Conduct hedgerow + forb addition analysis 3. Conduct new analysis assessing how phenologically continuous the hedgerow bloom actually is, in terms of pollinator needs (using an adaptation ofthe methodology we developed in M'Gonigle et al. 2016). 4. Develop research proposals for using SNPs and/or microsatellites to examine population demography of selected bee species colonizing hedgerows. Goal 3. 1. Continue work on 3 manuscripts initiated to date and submit for publication. 2. Continue additional collaborations leading to new syntheses and reviews of the impacts of diversification on biodiversity and ecosystem services in farmland.
Impacts
What was accomplished under these goals?
Goal 1. Reported thoroughly under CA-B-INS-0169-H: not repeated here Goal 2. We continued analyzing our extensive hedgerow database, collected over 10 years (see products). We published 5 papersand provide summariesof those studies below. We also conducted new analyses described below under the 4 questions. Finally, we created an outline for an invited book chapter review of the effects of hedgerows on pollinator populations, communities and services. How hedgerows, both locally and in the surrounding landscape, influence pollinator communities (occupancy and beta-diversity) and functional properties (response diversity and redundancy) We have found that hedgerows in the surrounding landscape exert a positive influence on colonization at other sites in the landscape (i.e. both hedgerows and controls), suggestingthat hedgerows may serve as sources. However, hedgerows in the surrounding landscape do not promote persistence at other sites in the landscape. Instead persistence is chiefly related to the floral diversity present locally at the site (Ponisio et al., in prep). In other analyses, we have also found that the floral diversity is strongly tied to the length of time post restoration; thus more mature hedgerows have greater floral diversity. Bee abundance, richness, evenness and diversity, as well as functional dispersion, all trackchanges infloral diversity as hedgerows mature (Kremen et al., in prep). For functional properties, we found that hedgerows increased the occurrence of pollinators known to visit common crops of the region. However, within guilds of bees that visited the same crop, hedgerows did not increase functional diversity or species redundancy. Thus, hedgerows may not increase the stability of crop pollination services for these crops, despite their clear functional effects over the whole pollinator community and on crop pollinators(Kearney et al, in prep). 3 manuscripts are in prep for this section. How restoration proceeds - how long does it take to restore pollinator communities and their functional properties? How does adding a forb layer to the hedgerow shrub influence the pollinator communities? We found that it takes about 5 years post-restoration to find consistent positive effects on bee species richness (Kremen et al. in prep). We are working on the analysis of the effects of adding a forb layer, which will be an additional manuscript. Based on the cost of hedgerow restoration and the flow of benefits to surrounding fields, who should restore hedgerows? (development of model/decision support framework) We found that based on both pollination and pest control, it takes 7 years for owners to recover the costs of installing and maintaining a hedgerow (Morandin et al. 2016, see below). Further work on decision support is in progress (see also M'Gonigle et al. 2016, below). Do hedgerows deliver not only pollen and nectar to foraging native pollinators, but also neonicotinoid pesticides? Field data of pollen, soils and bees were collected and our collaborator at USGS finalized the analysis of pesticide composition. Unfortunately, we found few neonicotinoids in our samples, but many other pesticides. The graduate student conducting this work is on leave for maternity and child-rearing, so this project is onhold. Publications Summaries: Ponisio, L et al. (2017) Ecology Letters, 20, 1261-1272. Using an 8-year dataset of ~ 20 000 plant-pollinator visitation records, we find that pollinator species occupy highly dynamic network positions through time, causing the assembly process to be punctuated by major network reorganisations. The most persistent pollinator species are also the most variable in their network positions, suggesting assembly occurs via an opportunistic rather than a preferential attachment process. M'Gonigle, L et al. (2016) Conservation Letters. 10, 105-111. We developed a tool that identifies a plant mix for habitat restoration that optimizes a variety of assessment criteria of the pollinator visitor community (e.g., pollinator visitation, richness, or phenology). We tested our tool and showedthat it identifies mixes that better satisfy these criteria than ones found using conventional expert-driven methods. Morandin et al. 2016. Journal of Economic Entomology. 109, 1020-1027. Our study documented that hedgerows are economically viable to growers by enhancing beneficial insects and natural pest control and pollination contributing to yield on farms, with a breakeven time of 7 years. Sardinas, H et al. 2016. Restoration Ecology. 24, 499-505. We evaluated the ability of native plant hedgerows to provide suitable nesting habitat and enhance nesting rates of ground-nesting bees. We found that, when compared to unmanaged field edges (controls), hedgerows did not augment most indicators of nest habitat quality or nesting rates. Sardinas, H et al, 2016. Ecological Applications. 26, 438-447. We examined the role of hedgerow plantings on nest incidence of ground-nesting bees in field margins and within monoculture, conventionally managed sunflower fields in California's Central Valley. We tracked bee movement into fields and used these data to simulate the distribution of pollination services within a crop field. Ground- nesting native bees nested both in fields and edges, and there was no effect of hedgerows on nesting or movement into fields. Based on an exponential decay rate of bee movement into fields and nesting locations, our data predict a heterogeneous distribution of pollination services within sunflower fields, with edges receiving higher coverage than field centers. Goal 3 We contributed to 3 syntheses/reviews that explore the role of agricultural diversification in maintaining biodiversity and ecosystem services in agricultural landscapes (summarized below), and two blogs (Other products). We are actively working on several more syntheses , including: A review of what we know and still need to know about how farm diversification above and below ground affects biodiversity and ecosystem services. A summary of the evidence of how diversification practices affect biodiversity and ecosystem services in Mediterranean agroecosystems(led by Gorm Schackelford using the Delphi method) An invited review for Science on future visions for reconciling biodiversity conservation and agriculture through farmland diversification Publication Summaries: Isbell, F. et al. (2017) Journal of Ecology, 105, 871-879. We found consistently strong evidence that strategically increasing plant diversity increases crop and forage yield, wood production, yield stability, pollinators, weed suppression and pest suppression, whereas effects of diversification on soil nutrients and carbon remain poorly understood. Lichtenberg, E. et al. (2017). Global Change Biology. DOI: 10.1111/gcb.13714. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity, and regional diversityof arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in-field plant diversity enhanced arthropod abundance and richness but decreased evenness, at both scales, but particularly locally. Kovács-Hostyánszki, A et al. (2017) Ecology Letters. 20, 673-689. We critically evaluate the potential of ecological intensification to reverse the land use and management trends currently degrading pollinator communities and potentially causing widespread pollination deficits. Our findings support ecological intensification as a solution to pollinator declines, and we discuss ways to promote it in agricultural policy and practice.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Karp, D. S., R. Moses, S. Gennet, M. S. Jones, S. Joseph, L. K. MGonigle, L. C. Ponisio, W. E. Snyder, C. Kremen. 2016. Agricultural practices for food safety threaten pest control services for fresh produce. Journal of Applied Ecology. 53, 1402-1412. DOI: 10.1111/1365-2664.12707.
This work looks at the role of surrounding natural habitat on pest control by natural enemies, and is not part of the Goal 1 project reported separately to USDA).
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Ponisio, L., Gaiarsa, M.P., C. Kremen (2017) Opportunistic attachment assembles plant-pollinator networks. Ecology Letters, 20, 12611272. DOI: 10.1111/ele.12821
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
MGonigle, L. K., N. M. Williams, E. Lonsdorf, C. Kremen. (2016) A tool for selecting plants when restoring habitat for pollinators. Conservation Letters. 10, 105-111. DOI: 10.1111/conl.12261
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Morandin, L.A., R. Long, C. Kremen. 2016. Pest control and pollination cost benefit analysis of hedgerow restoration in a simplified agricultural landscape. Journal of Economic Entomology. 109, 1020-1027. DOI: 10.1093/jee/tow086
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Sardinas, H. S., L. C. Ponisio, and C. Kremen. 2016. Hedgerow presence does not enhance indicators of nest-site habitat quality or nesting rates of ground-nesting bees. Restoration Ecology. 24, 499505. DOI: 10.1111/rec.12338.
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Sardinas, H. S., K. Tom, L. C. Ponisio, A. Rominger, and C. Kremen. 2016. Sunflower (Helianthus annuus) pollination in Californias Central Valley is limited by native bee nest site location. Ecological Applications. 26, 438-447. DOI: 10.1890/15-0033.
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Isbell, F., Adler, P., Eisenhauer, N., Fornara, D., Kimmel, K., C. Kremen, Letourneau, D., Liebman, M., Polley, H., Quijas, S. & Scherer-Lorenzen, M. (2017) Benefits of increasing plant diversity in sustainable agroecosystems. Journal of Ecology, 105, 871879. DOI: 10.1111/1365-2745.12789
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Kov�cs-Hosty�nszki, A., Esp�ndola, A., Vanbergen, A.J., Settele, J., C. Kremen, Dicks, L. V. (2017) Ecological intensification to mitigate impacts of conventional intensive land use on pollinators and pollination. Ecology Letters. 20, 673689. DOI: 10.1111/ele.12762
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Lichtenberg, E.M., Kennedy, C.M., C. Kremen, Bat�ry, P., Berendse, F., Bommarco, R., Bosque-P�rez, N.A., Carvalheiro, L.G., Snyder, W.E., Williams, N.M., Winfree, R., Klatt, B.K., �str�m, S., Benjamin, F., Brittain, C., Chaplin-Kramer, R., Clough, Y., Danforth, B., Diek�tter, T., Eigenbrode, S.D., Ekroos, J., Elle, E., Freitas, B.M., Fukuda, Y., Gaines-Day, H.R., Grab, H., Gratton, C., Holzschuh, A., Isaacs, R., Isaia, M., Jha, S., Jonason, D., Jones, V.P., Klein, A.-M., Krauss, J., Letourneau, D.K., Macfadyen, S., Mallinger, R.E., Martin, E.A., Martinez, E., Memmott, J., Morandin, L., Neame, L., Otieno, M., Park, M.G., Pfiffner, L., Pocock, M.J.O., Ponce, C., Potts, S.G., Poveda, K., Ramos, M., Rosenheim, J.A., Rundl�f, M., Sardi�as, H., Saunders, M.E., Schon, N.L., Sciligo, A.R., Sidhu, C.S., Steffan-Dewenter, I., Tscharntke, T., Vesel�, M., Weisser, W.W., Wilson, J.K. & Crowder, D.W. (2017) A global synthesis of the effects of diversified farming systems on arthropod diversity within fields and across agricultural landscapes. Global Change Biology. DOI: 10.1111/gcb.13714
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