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While the impacts of cigarette smoking on human health are widely known, a less recognized impact of tobacco product use and disposal is environmental pollution. This review discusses the current literature related to cigarette and e-cigarette contamination in the context of environmental sources and impacts, with a focus on the documented influences on biota, ranging from bacteria to mammals. Cigarette butts and electronic cigarette components can leach contaminants into soil, water, and air. Cellulose acetate cigarette filters comprising the butts are minimally degradable and are a source of bulk plastic and microplastic pollution, especially in aquatic ecosystems where they tend to accumulate. Cigarette combustion and aerosol production during e-cigarette use result in air contamination from sidestream, exhaled, and thirdhand pathways. The chemical byproducts of tobacco product use contaminate wastewater effluents, landfill leachates, and urban storm drains. The widespread detection of nicotine and cotinine in the environment illustrates the potential for large-scale environmental impacts of tobacco product waste. Studies show that cigarette butt leachate and nicotine are toxic to microbes, plants, benthic organisms, bivalves, zooplankton, fish, and mammals; however, there remain critical knowledge gaps related to the environmental impacts of tobacco product waste on environmental health and ecosystem functioning.

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Riding the global waves of decriminalization, medical or recreational use of cannabis (Cannabis sativa spp.) is now legal in more than 50 countries and U.S. states. As governments regulate this formerly illegal crop, there is an urgent need to understand how cannabis may impact the environment. Due to the challenges of researching quasi-legal commodities, peer-reviewed studies documenting environmental impacts of cannabis are limited, slowing the development of policies and agricultural extension guidelines needed to minimize adverse environmental outcomes. Here we review peer-reviewed research on relationships between cannabis and environmental outcomes, and identify six documented impact pathways from cannabis cultivation (land-cover change, water use, pesticide use, energy use, and air pollution) and consumption (water pollution). On the basis of reviewed findings, we suggest policy directions for these pathways. We further highlight the need to formalize existing traditional and gray literature knowledge, expand research partnerships with cannabis cultivators, and ease research restrictions on cannabis. Finally, we discuss how science might contribute to minimize environmental risks and inform the development of regulations for a growing global cannabis industry.

ABSTRACT. Despite extensive research focused on increasing the sustainability and productivity of agricultural systems in the tropics, adoption rates of improved management solutions often remain low among smallholder farmers. To address this, we evaluated how local knowledge and perceptions influenced decision-making processes among smallholder cocoa farmers. We conducted individual semistructured interviews with 72 cocoa farmers in Southeast Sulawesi and documented local knowledge about soil fertility indicators, nutrient cycling processes, and the interactions among shade trees, cocoa trees, and soils in cocoa agroforests. We further collected data regarding farmers' fertilizer preferences, additional income sources, and perceived barriers to improved cocoa production. We found that farmers' understanding of biophysical interactions in Southeast Sulawesi was comprehensive, mostly accurately aligned with scientific literature, and sometimes provided additional complementary knowledge. Cocoa farmers in Southeast Sulawesi approached decision making in a holistic way, integrating personal observations, information from external sources, and socioeconomic limitations and priorities. This finding highlights the value of flexible conservation farming approaches that allow farmers to minimize trade-offs and prioritize their households' needs. Finally, we identify a "dual" knowledge gap on the part of farmers and scientists regarding the direct benefits of shade tree inclusion for improved yields and income security. Addressing this through further research and targeted knowledge dissemination could contribute to an increase in the long-term adoption rates of more sustainable cocoa cultivation practices.

Despite the increasingly widespread use of the term agroecology by farmers, scientists, agrarian social movements, and lawmakers, the definition of the concept is still the object of controversies. Current interpretations range widely, from fully transdisciplinary and interdisciplinary definitions integrating ecological, socioeconomic, and political dimensions of agriculture, to more narrow definitions of agroecology as a discipline bridging ecology and agronomy. No less importantly, few actors have developed criteria and methodologies to identify and evaluate agroecological systems based on both ecological and socioeconomic dimensions. The lack of consistency in the study and application of "agroecology," resulting from varying definitions for agroecology and the absence of standardized methodologies to identify agroecological systems, is problematic. It limits the recognition of associated benefits and disadvantages of different agroecological systems, as well as the identification of drivers that favor the implementation of agroecological practices. While lessons learned from individual case studies are valuable and showcase the potential of agroecology, results are not always relevant to other contexts. Here, we review existing theoretical and empirical agroecological literature. The major points that emerge are the following: (1) we integrate six historical ecological principles with seven socioeconomic principles to propose an overarching framework for recognizing systems oriented towards agroecology; (2) the implementation of different principles may vary greatly across spatial scales or governance contexts; (3) there are numerous barriers that farmers may face in their transition towards an agroecological "ideal"-this highlights the need for improved recognition of systems in transition, as well as the need for supportive policies to scale up agroecology. The application of two complementary methodological approaches presented in our review has the potential to help practitioners evaluate to what extent a system can be considered as agroecological based on ecological and socioeconomic principles.

griculture in the United States has undergone massive consolidation over the past 50 years and the same is true in California. Several economic and market factors have contributed to farm consolidation, but new regulations on agriculture have also played a role (Dunn 2003; Howard 2015). Compliance costs associated with increased regulatory burdens can decrease producer profits and limit market entry (Thilmany and Barrett 1997). Small producers may be particularly harmed by the need to achieve compliance, as economies of scale provide larger producers an advantage (Dean et al. 2000). Small firms may lack sufficient capital to change production methods to comply with regulations, or even to manage the burdens associated with reporting. (See McCullough et al. 2017 for a more comprehensive discussion of regulatory costs to California farmers.) The cannabis industry has historically resisted widespread farm consolidation, perhaps due to its

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