State-led agricultural subsidies drive monoculture cultivar cashew expansion in northern Western Ghats, India

Agricultural commodity production constitutes an important livelihood source for farmers but significantly contributes to tropical deforestation and biodiversity loss. While the socioecological effects of agricultural commodities such as palm oil, cocoa and coffee are well studied, the effects for commodities such as cashew (Anacardium occidentale) have received less attention. Global cultivated area for cashew increased rapidly from 526,250 ha in 1980 to ~5.9 million ha in 2018. India is the world's second largest cashew producer, with cashew farms often occurring adjacent to remnant forests. To mitigate deforestation for cashew expansion, it is necessary to understand present-day land use policies and management practices that drive this expansion. Through semi-structured interviews (n = 65) and a literature review on agricultural policies in India, we evaluated the role of state-led land use policies in cashew expansion and characterised present-day cashew farming systems in the Sawantwadi-Dodamarg landscape in India. Agricultural subsidies introduced from 1980s to 1990s encouraged cultivar cashew expansion and influenced land use conversion from rice and privately owned forest to cashew. Farmers preferred cultivar cashew as they produced higher yields faster, although they required more agrochemical inputs and were susceptible to pests and wildlife depredation. About 80% of farmers had planted cashew farms by clearing forests in the past 30 years and expressed interest to continue the same. Farmers avoided applying for government-sponsored compensation for crop losses due to wildlife depredation and chose instead to expand cultivar cashew into forested areas. Our study deepens the understanding of how government-led agricultural subsidies drive farmers' uptake of cashew cultivars, farmers' cashew management practices, and how these factors drive deforestation in this landscape at the state and farm level. We recommend further research with equitable stakeholder participation in cashew farming systems to devise sound planning for forest conservation and sustainability standards for the cashew industry.Ministry of Education (MOE)National Research Foundation (NRF)Published versionThis work was supported by the Singapore Ministry of Education Academic Research Fund Tier 1 RG145/19 Grant secured by J.S.H.L. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. This research was supported by the Earth Observatory of Singapore via its funding from the National Research Foundation Singapore and the Singapore Ministry of Education under the Research Centres of Excellence initiative

Mammals make use of cashew plantations in a mixed forest-cashew landscape

Heterogeneous landscapes harboring mosaics of natural habitat and agriculture are increasingly gaining conservation focus in the tropics. While research on cash crops such as coffee, rubber, and oil palm has led to an understanding of their role as supplementary habitats, such has remained limited in cashew plantations despite it being a cash crop of global significance. We conducted a study to understand the occurrence of terrestrial mammal species in a mixed forest–cashew landscape in the northern Western Ghats, India. During January to April 2016, we used trail cameras to sample a total area of 25 km2 divided into 100 grid cells of 0.25 km2 each. We deployed six trail cameras for a 24 h period in each grid cell and obtained photo-captures of 11 species in forests, of which nine were detected in cashew plantations, but most species showed low capture rates. For three of these species—Indian crested porcupine, sambar, and wild pig—we modeled habitat use as a function of site-specific attributes. Wild pig showed a higher probability of use of cashew than forest, while porcupine and sambar did not show any pronounced differences between the two land uses. The probability of habitat use by sambar and porcupine was positively influenced by undergrowth but not for the wild pig. Wild pig habitat use was positively related to increased proximity of human settlements and increasing distance to forests, but the pattern was unreliable for sambar and porcupine. Our preliminary study demonstrates that a subset of terrestrial mammals in the forest makes use of cashew plantations and highlights the need for further research in forest–cashew landscapes to assess conservation opportunities.Ministry of Education (MOE)Published versionFunding for this work was provided by core grants to NCBS-TIFR by the Department of Atomic Energy (India) and a program grant from the Tata Trusts. AR received support from the Tier 1 project grant: Singaporean Ministry of Education Tier 1 RG145/19. This work comprises EOS contribution number 339

Mapping cashew monocultures in the Western Ghats using optical and radar imagery in Google Earth Engine

Tropical deforestation is increasingly driven by the expansion of agricultural commodity production. Mapping commodity crops is an important step towards monitoring commodity-driven deforestation. Advances in remote sensing technology, such as the availability of high-resolution imagery and the combination of optical and radar imagery have enabled the detection of the tree-like crops which are difficult to distinguish from forest cover. Cashew is an example of a tree-like crop that grows in areas with high forest cover and biodiversity. Cashew is reported to occupy ∼7.1 million ha globally yet mapping it has been constrained by unclear boundaries due to spatial mixing with forests, an indistinct spectral signature, and structural composition that resembles forests. We employed optical, radar, and a combination of the two imagery types to detect and map cashew monocultures in south Maharashtra, India for 2020. We performed a land cover classification on Google Earth Engine using Random Forest, Classification And Regression Trees and Support Vector Machine algorithms. The combination of Sentinel-2 and Sentinel-1 SAR imagery using Random Forest algorithm yielded the highest unbiased overall accuracy (83%) and unbiased producer's and user's accuracies of 71% and 86% respectively for cashew land cover and was considered the best approach. According to our best approach, monoculture cashew plantations occupy 53,350.37 ha of total land area in the Sawantwadi- Dodamarg landscape in India. This study shows that a combination of optical and radar imagery can be used for cashew land cover classification in the Western Ghats, and future studies could modify these methods for cashew mapping in other landscapes. This study contributes to a growing body of literature supporting the use of both optical and radar imagery for detecting tree-like crop cover.Ministry of Education (MOE)National Research Foundation (NRF)Published versionFunding for the study was provided by the Singaporean Ministry of Education Academic Tier 1 Research Funds (RG145/19 (NS)) and the Navjot Sodhi Conservation Research Award 2021. This research was supported by the Earth Observatory of Singapore via its funding from the National Research Foundation Singapore and the Singapore Ministry of Education under the Research Centres of Excellence initiative

How activist should scientists be?

On a Friday evening in late September 2019, 21 PhD students from every continent but Antarctica gathered in a dimly lit room on the second floor of Sophienstraße 22a in Berlin. This was the climax of a week-long summer school on ‘Transformative Human-Environment Research & Participatory Methods’ organised by the IRI THESys at Humboldt University. The preceding week’s lectures, discussions, and practicums on the democratization of knowledge production were fresh in everyone’s minds. Should scientists strive to be objective? Is it possible (not) to align our values with our scientific practice? What counts as ‘science’? The summer school students and faculty, as well as a handful of members of the public, took their seats among a few rows of chairs. At the front of the room were five chairs arranged in a semicircle facing the audience. The moderator, Krystin Unverzagt, welcomed the audience and explained how the event would proceed. Unlike a typical panel, this would be a ‘fishbowl’ discussion; the moderator would take the central chair, and each time an audience member wanted to add to the discussion, they would walk to the front, take a seat, and make their point. They were then free to stay for a few responses or return to the audience. Regardless of the direction of the conversation, one seat in the front would remain open, so there was always the opportunity for someone new to join. The following is a reconstruction of the ensuing conversation, collaboratively assembled by the participants the following day. The editors—themselves participants of the event—have added headings and made slight changes to wording for stylistic consistenc

Crop and landscape heterogeneity increase biodiversity in agricultural landscapes: A global review and meta‐analysis

Agricultural intensification not only increases food production but also drives widespread biodiversity decline. Increasing landscape heterogeneity has been suggested to increase biodiversity across habitats, while increasing crop heterogeneity may support biodiversity within agroecosystems. These spatial heterogeneity effects can be partitioned into compositional (land-cover type diversity) and configurational heterogeneity (land-cover type arrangement), measured either for the crop mosaic or across the landscape for both crops and semi-natural habitats. However, studies have reported mixed responses of biodiversity to increases in these heterogeneity components across taxa and contexts. Our meta-analysis covering 6397 fields across 122 studies conducted in Asia, Europe, North and South America reveals consistently positive effects of crop and landscape heterogeneity, as well as compositional and configurational heterogeneity for plant, invertebrate, vertebrate, pollinator and predator biodiversity. Vertebrates and plants benefit more from landscape heterogeneity, while invertebrates derive similar benefits from both crop and landscape heterogeneity. Pollinators benefit more from configurational heterogeneity, but predators favour compositional heterogeneity. These positive effects are consistent for invertebrates and vertebrates in both tropical/subtropical and temperate agroecosystems, and in annual and perennial cropping systems, and at small to large spatial scales. Our results suggest that promoting increased landscape heterogeneity by diversifying crops and semi-natural habitats, as suggested in the current UN Decade on Ecosystem Restoration, is key for restoring biodiversity in agricultural landscapes