Claire Kremen, Professor

Closed (1) Insect Diversity in Agroecology Internship

Applications for Spring 2018 are now closed for this project.

Over the last half-century, conversion of land for agriculture has been a major driver of biodiversity loss. The tension between agriculture and biodiversity conservation will only become more acute in the near future, as human food demand is estimated to double by 2050. Beyond direct land use, conventional agriculture’s reliance on chemical pesticides negatively impacts both ecosystems and human health.

Monterey County, comprising much of California’s Central Coast, is not only one of the world’s most productive agricultural regions, it is also a pesticide hotspot. A recent report by the California Department of Public Health revealed that Monterey County has the highest percentage of public schools within a quarter-mile of the heaviest use of several categories of hazardous pesticides. Correlations between pesticide exposure and negative health impacts on farmworker families have been extensively documented in this region.

In a world of land scarcity, increasing food demand, and pesticide concerns, how can agricultural land use be balanced with conserving biodiversity and protecting human health?

The increased adoption of diversified farming practices is a potential solution. By promoting agricultural practices that simultaneously maintain high yields and support biodiversity, win-win solutions for humanity and the rest of nature may be achieved. Research shows that diversified farming systems with features such as non-crop plantings and complex landscape mosaics can positively influence ecosystem services, including soil retention, resilience to extreme weather, pollination, and pest control, although in some instances this can result in lower yields. This project studies the mechanisms underlying the effects of non-crop vegetation on biological pest control ecosystem services in organic strawberry fields. Clarifying these mechanisms will not only inform the management of agricultural lands for the dual goals of crop production and biodiversity maintenance, it may also contribute to reducing pesticide-related health risks and raising society’s valuation of pest control ecosystem services.

Students will be involved in laboratory tasks that include sorting and identifying arthropod specimens and entering data. Students with experience in statistics and R-programming will have the chance to analyze existing data and contribute to writing up the results. There may also be opportunities to help with GIS software to quantify land cover data, depending on experience and interest.

Day-to-day supervisor for this project: Adrian Lu, Ph.D. candidate

Qualifications: Interest in agroecology, entomology, and/or conservation is required. Must be detail-oriented, patient, and intellectually curious. Experience in GIS, microscopy, insect curation, statistics, R-programming, and/or Microsoft Excel is useful but can be taught during the internship.

Weekly Hours: to be negotiated

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Closed (2) Cacao pollination & Conservation benefits of agroforestry

Applications for Spring 2018 are now closed for this project.

We have two projects available, one in the lab and one on a literature review, for those with experience and interest.

The lab work will be focused on a project that examines the pollination biology of cultivated cacao in Ecuador. Theobroma cacao, an understory tree native to the Upper Amazon Basin, has an intriguing fly-based pollination system that is understudied even though cultivated varieties experience very low pollination rates. This study aims to determine how different management strategies and landscape contexts affect natural pollination levels in this globally important crop. We estimate pollination service to fields by comparing open and hand pollination treatments. In addition, we collected floral visitors to cacao in order to correlate pollination service to pollinator community composition.

The literature review will focus on agroforestry methods and results in regards to conservation targets. Agriculture covers an estimated 40% of the Earth's terrestrial land surface, and demand for agricultural products is expected to increase in the near future. Deforestation and conversion of grasslands for agriculture are major conservation concerns disproportionately affecting tropical biomes, even as these ecosystems have a higher proportion of biodiversity than temperate biomes. Agroforestry and agroecological methods have been proposed as ways to reconcile biodiversity conservation and agriculture in tropical areas. After many years of individual studies, there is finally enough research to judge this sentiment on scientific grounds.
For this project, we are compiling a database of agroforestry/agroecological papers focusing on biodiversity conservation around the world from the past 40 years and review this body of literature in terms of methods, focus crops, and tropical biome as well as perform a meta-analysis on their results if possible.

For cacao pollination: Under the supervision of a senior biologist, the undergraduate student will help with all aspects of lab processing of collected specimens. This is interesting but mostly repetitive laboratory tasks that include sorting and labeling specimen samples, pinning insects, identifying insects to order and family, using GIS software to quantify land cover data and entering data. If there is interest, the undergraduate could be involved in identifying some groups of insects to family or genus/species (most likely tropical ants). The student will be given time at the beginning of their tenure to read summaries, questions and review preliminary results in order to understand the project in a larger context.

For the literature review: With the support of a senior biologist, the student will help to compile the database of papers used in this comprehensive review and meta-analysis. The undergraduate will read abstracts and articles in order to determine if journal articles should be included in the review and to harvest pertinent information from the articles.

Day-to-day supervisor for this project: Emily Kearney, Ph.D. candidate

Qualifications: Interest in entomology, agroecology and conservation. Working familiarity with insect orders and taxonomic keys preferred for the lab position but not required. Some experience critically reading scientific articles and a basic knowledge of statistics is preferred for the agroforestry project but not required. Initiative, attention to detail, patience, and self-motivation are essential.

Weekly Hours: to be negotiated

Closed (3) Below- and aboveground connections in pollination

Applications for Spring 2018 are now closed for this project.

Belowground organisms influence pollinator behavior. Soil communities are extremely diverse, and when their interactions with plants influence floral characteristics, they have the potential to alter pollinator attraction and visitation. Plant–pollinator interactions have been neglected in studies of the direct and indirect effects of soil organism–root interactions.

Our research will explore these belowground interactions, focusing on the effects of arbuscular mycorrhizal fungi (AMF) and their effects on floral traits, specifically on strawberry plants. We will maintain strawberry plants inoculated with various AMF strains in the greenhouse and determine the effect of AMF on pollinator traits (floral display, pollen and nectar composition, and fruit and seed set). This study will further our understanding of ecological processes between soil microbes, plants, and pollinators that can inform land management strategies in agriculture and conservation biology.

Undergraduate students will be mostly involved in helping prepare and maintain the greenhouse experiment and collecting samples in the field. In addition, they will be required to collect various pollinator traits measurements (floral display, pollen and nectar composition, and fruit and seed set) and soil composition measurements (nutrients and mycorrhizal colonization) throughout the experiment. This an excellent opportunity for students interested in gaining experience in plant ecology research in controlled environments.

Day-to-day supervisor for this project: Aidee Guzman, Graduate Student

Qualifications: Interest in plant ecology, soil science, microbial ecology, and agroecology. Past experience in greenhouse management or field work is good but not required.

Weekly Hours: 6-9 hrs

Closed (4) Meta-analysis: ecosystem services in diversified agriculture

Applications for Spring 2018 are now closed for this project.

A number of case studies have demonstrated that diversifying agriculture has the potential to provide ecosystems services including pollination, pest and disease control, agricultural yield, and potentially a buffer against climate change. However, which species are responsible for diversity effects and the generality of effects across systems is unclear. Synthesis of the published literature is needed. This project will focus on reviewing the published literature and conducting a meta-analysis to determine how diversifying agriculture can suppress insect pests and diseases of crop species. The approach will take advantage of phylogenetic relatedness and functional trait diversity of plants in fields to better understand effects of disease and pest pressure.

This is a special project that is looking for skilled, enthusiastic, and motivated students. Students will mostly be involved in conducting a standard literature review, extracting data from published papers that meet our inclusion criteria, and helping with statistical analysis of the extracted data.

This project will be a unique opportunity for students to experience the process of conducting meta-analyses, which is seldom offered to students at the undergraduate level. Students will also be exposed to the process of designing literature searches using ISI web of science, designing inclusion criteria, statistical analysis, scientific writing, and publishing. Students will have the potential for authorship, if they show dedication to the project and substantially contribute to the different stages.

Day-to-day supervisor for this project: David Gonthier, Post-Doc

Qualifications: Applicants need to have experience and enjoy reading the scientific literature and be able to scrutinize the details of published studies. Applicants should also have experience with the use of excel. We are seeking students with high enthusiasm for biodiversity science, agroecology, and sustainable food systems.

Weekly Hours: to be negotiated