Friday, July 1, 2022

July 2022 science summary

Bromeliad fly (Copestylum) on spiderwort (Tradescantia)


This month is another grab bag: one paper on equity in fire management, two on biodiversity data, one asking how much conservation has helped species, and one pretty bad one on how ag practices impact nutrients.

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Anderson et al. 2020 found that rich white communities who had a fire nearby tend to get additional prescribed fire (even when not needed). This is partly due to their ability to self-advocate at relevant planning meetings. It raises equity and social justice concerns about how we could instead base fire management on factors like social and/or ecological vulnerability. As context, here is a map showing how wildfire risk varies across the U.S.:

Saran et al. 2022 has a good overview of biodiversity information portals, 16 global (Table 1) and 5 country-specific (from Australia, Canada, India, and the U.S., Table 2). It's a great complement to Nicholson et al. 2021 (an overview of ecosystem indicators) by providing actual data sources and some info about what each portal includes. The paper certainly isn't "comprehensive" as the title advertises, but it's a great start and I learned about some new useful resources by reading it.

Before threatened species can get protection, they need to be assessed to document how vulnerable they are. But there is a substantial backlog of species waiting to be assessed. Levin et al. 2022 offers a fairly simple (but ultimately unsuccessful) way to re-prioritize unassessed species for the IUCN red list to allow a better chance of assessing the ones that are in trouble so they can get protection. They use a rapid estimate of "extent of occurrence" (the species' range and spatial distribution of threats) as a proxy for vulnerability. At first it's exciting to see that it was 92% accurate at identifying which species were of the Least Concern (showing potential to flag species not worth assessing). But two questions are more relevant (and Fig 1 has the answers): what % of vulnerable species does it correctly recommend assessing (40%) and what % of recommendations for assessment are for species that are actually vulnerable (23%). The discussion has interesting notes on some of the aspects that confused the model (like 5 ash app threatened by Emerald Ash Borer and the American Chestnut threatened by blight) - widespread spp. hit hard by invasives are challenging to accurately assess using simple approaches like this. Hopefully the next iteration of the tool will be more successful, if they could substantially reduce false negatives for vulnerable species it could provide assessment priorities directly, or if they could substantially reduce false positives for vulnerable species it could help by indicating species that likely shouldn't be assessed.

Jellesmark et al. 2022 is a global (see Fig 1 map) preprint looking at how conservation has impacted targeted vertebrate species (by comparing pairs of populations targeted for conservation with those in the same country that did not receive conservation attention). I honestly don't know enough about the underlying data source (Living Planet Database) to speak to the reliability of their results (I'll wait for peer review for that, there is at least one very important typo where they use "invertebrate" when they clearly mean "vertebrate"). They found that population size of assessed vertebrates dropped 24% over 46 years, but estimate that without conservation it would have dropped 32% (and this likely underestimates the impact of conservation). They split out conservation actions into 7 groups (land/water protection, land/water mgmt, species mgmt, education/awareness, law/policy, livelihoods/incentives, and external capacity building), and capacity building followed by the first three showed the strongest results (Fig 5).

Montgomery et al. 2022 asks how nutrients from ‘regenerative’ farms (that use no-till, crop  rotations, and cover crops) differ from other farms, but I wouldn't recommend it. This paper is pretty weak methodologically, results were inappropriately highlighted and over-interpreted, and the results I initially planned to write about didn’t hold up when I looked at raw data. Some key caveats: it is a very small sample size, 4/5 authors have financial interests the paper furthers, only one author appears to be a scientist (a geomorphologist), and the methods are thin and read like they may have gone looking for pairs of farms that would support the desired narrative (plus they used a very rough method to measure organic matter). At first I thought the most interesting / meaningful results are for cabbage: 10 assessed nutrients were substantially higher on regenerative farms, compared to 4 that were the same, 4 that were substantially lower, and 3 not assessed. But when you dive in, that 70% difference in vitamin E is from 0.004 to 0.007 mg/100g (essentially nil). Ditto with wheat results, 50% more calcium than “almost none” is still almost none. The animal results are hard to interpret because they don’t provide enough detail on differences between ‘regenerative’ vs. ‘conventional’ (although findings that grass-finished beef have more nutrient content have been reported in other lit, in alignment w/ results here). Some results look more meaningful (20% more vitamin C in cabbage is worthwhile) but there is such variation in the soil organic matter and soil health across the farms it’s really hard to know what is significant and what is accidental. One last note - 'regenerative' here almost certainly means 'genetically modified’ for most crops, since it’s hard to do no-till without them.


Anderson, S., Plantinga, A., & Wibbenmeyer, M. (2020). Inequality in Agency Responsiveness: Evidence from Salient Wildfire Events (Issue December).

Jellesmark, S., Blackburn, T. M., Dove, S., Geldmann, J., Visconti, P., Gregory, R. D., McRae, L., & Hoffmann, M. (2022). Assessing the global impact of targeted conservation actions on species abundance. BioRxiv, 2022.01.14.476374.

Levin, M. O., Meek, J. B., Boom, B., Kross, S. M., & Eskew, E. A. (2022). Using publicly available data to conduct rapid assessments of extinction risk. Conservation Science and Practice, November 2020, 1–9.

Montgomery, D. R., Biklé, A., Archuleta, R., Brown, P., & Jordan, J. (2022). Soil health and nutrient density: preliminary comparison of regenerative and conventional farming. PeerJ, 10, e12848.

Saran, S., Chaudhary, S. K., Singh, P., Tiwari, A., & Kumar, V. (2022). A comprehensive review on biodiversity information portals. Biodiversity and Conservation, 0123456789.

p.s. This photo is of what I think is a bromeliad fly (Copestylum) on a Tradescantia flower in my garden. First time I have seen one!

No comments:

Post a Comment

Questions, comments, suggestions, and complaints welcome.