68. Humus, satellites, and sandwiches

Hi. If you are new here, I am Rhishi Pethe, and I am excited you’re in the “Software is Feeding the World'' community. Every Sunday, you will receive this free newsletter at the intersection of technology and agriculture systems. I am a product manager at Project Mineral (focused on sustainable agriculture) at X, the moonshot factory. The views expressed in this newsletter are my personal opinions.

Programming Note: The newsletter will take a break for August 8th, 2021. It will return on August 15th, 2021.

Carbon and Soil

A major theme for carbon sequestration in agriculture involves paying farmers for sequestering carbon based on their farming practices. The actual payment will depend on the quantity of carbon sequestered. It requires careful and dependable measurement of the carbon sequestered, either using direct measurements, or using model based approaches (and most probably a combination of measurement and model based approaches.)

The measurement, and especially the models require the understanding of how soils carbon sequester carbon, what does the process look like, and what factors drive carbon sequestration. A majority of this has been based on a specific understanding of carbon within soil, and new research is thoroughly questioning the understanding. From a recent article, A Soil-Science Revolution Upends Plans to Fight Climate Change

...molecules, collectively called humus, have long been a keystone of soil science; major agricultural practices and sophisticated climate models are built on them.

What is humus? According to the National Geographic definition,

Humus is dark, organic material that forms in soil when plant and animal matter decays.

The thick brown or black substance that remains after most of the organic litter has decomposed is called humus.

New studies using modern microscopes, and imaging has shown that humus is not a long lasting substance. From a simplification standpoint, existing models completely ignore the microorganisms present in the soil, whereas it is required that soil models represent soil which reflects reality more closely, a complex, three-dimensional environment governed by a hyper-diverse community of carbon-gobbling bacteria, fungi and other microscopic beings.

Some of the implications of this are clear. The methods and processes to measure carbon stock and flow are nascent, and need to become much more consistent and reliable, to support an open, transparent and functional market. Some of the models used to predict GHG impacts of farming might be overly optimistic about soil’s ability to trap and sequester carbon. There is an opportunity for new science, and new startups (for example, Trace Genomics) that focus on a more comprehensive understand of soil characteristics.

My key takeaway in “36. Carbon Markets: The substack of ag” was,

Carbon market exuberance is good for the long term, as it has the potential to address multiple issues like farmer profitability, soil health, and climate change and food production systems have a role to play.

This is playing out in real time. The exuberance of carbon markets (and other factors) is making us look at the science of soil health, and climate change much more closely. It means: 

1. We will have to temper the euphoria behind carbon sequestration, and follow a scientific approach.

2. We should be careful to align incentives, and actions with the real impact to mitigate climate change.


Cropland reduction through productivity increases

As I highlighted in 67. Drivers for digital transformation,

According to the Breakthrough Institute, most of the GHG reductions come from land use change. It is based on the assumption that increased crop production in one location leads to a proportional decrease in production and related land-use change elsewhere.

Land use change is a key driver for GHG emissions. But this is a very complicated topic. Latest research based on data from 2008-2016, published in “Nature Communications” showed that “Cropland expansion in the United States produces marginal yields at high costs to life.1” About 7 out of 10 new cropland areas produced yields below the national average, with a mean yield deficit of 6.5%.

Fig. 1: Net cropland conversion 2008–16

Rates of net conversion calculated as gross cropland expansion minus gross cropland abandonment and displayed as a percentage of total land area within non-overlapping 3 km × 3 km blocks. Net conversion was most concentrated in the eastern halves of North and South Dakota, southern Iowa, and western portions of Kansas, Kentucky, and North Carolina.

Grasslands, including those used for pasture and hay, constituted 88% of the land converted to crop production across the US.

Expected corn and soybean yields were lowest in the expansion hotspots of the northern and southern Plains, where new croplands frequently achieved just half of the nationwide average yields of existing croplands

Fig. 3: Yield differentials of new croplands compared to existing croplands.

Yield differential values represent the yields of new croplands relative to the yields of existing croplands nationwide (a–c) or within immediate 10 km x 10 km neighborhoods (d–f).  Yields of new croplands planted to corn and soybeans were typically lower than the national average (a, b) and the nearby local average (d, e) of existing croplands for each crop. Yields of new croplands planted to wheat were generally higher than the corresponding national average (c) but lower than nearby existing croplands (f).

The study shows that croplands are moving to lower-quality land in less-suitable regions. It is a double whammy for yield gains and cropland expansion.

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Sandwich-sized satellites offer data connectivity

Sensors and IoT devices in agriculture are spawning at a great rate, and are expected to do so over the next decade. According to a report by the IoT World Congress,

BI Intelligence survey expects that the adoption of IoT devices in the agriculture industry will reach 75 million in 2020, growing 20% annually. At the same time, the global smart agriculture market size is expected to triple by 2025, reaching $15.3 billion (compared to being slightly over $5 billion back in 2016).

Smart farming based on IoT technologies enables growers and farmers to reduce waste and enhance productivity ranging from the quantity of fertilizer utilized to the number of journeys the farm vehicles have made, and enabling efficient utilization of resources such as water, electricity, etc.

These IoT devices will require connectivity, which is a challenge in rural areas. Different technologies, including satellite constellations continue to enhance the level of connectivity available in different parts of the world. Swarm technologies is sending sandwich sized devices up in the air, to provide connectivity for data gathering tools lie soil moisture probes, or weather stations. 

Swarm’s 1 one-pound satellites are launched in low earth orbit in groups. The company launched 28 satellites in orbit to provide almost comprehensive coverage of the world throughout the day.

The current data plan with an annual contract provides 750 data packets per device per month, with 192 bytes per packet and can cost $ 5 / month. This is about a tenth of an MB of data transferred for $ 5 per month. For comparison, a typical 4 minute song is about 4 MB and so the monthly quota at that price is 6 seconds of a typical song. This will require creative design, with the sensors only sending meta-data to send high priority and timely alerts, and will have to wait for other connectivity to transmit other low priority data later.

Talking about satellites, Earthdaily Analytics announced plans to construct a new generation of satellites launching in 2023. The new satellites will collect scientific-grade imagery of the planet in a unique combination of 21 spectral bands, many of which will be 5-meter resolution. The constellation will have an expected lifespan of over 10 years.

Earthdaily Analytics wants to provide a full stack of capabilities in data services, satellite processing, machine learning and actionable insights.

Drones in high value use cases

Ukraine is one of the world’s largest sunflower oil producers and exporters. Ukraine has also seen a much more rapid adoption of drone spraying compared to other markets in the world.  

The spray drones are widely used in cultivated sunflower crops which account for over 20% of Ukraine's arable land area. Ukraine is known as the world's largest sunflower oil producer and exporter.

Drones have a leg up (literally) compared to tractors in certain situations. They can react much faster, can perform spraying right after rains in inaccessible wetlands, use less chemicals and do not damage the soil. The pilot controlled XAG agricultural drones can spray from 4 meters above the canopy on the pre-programmed path. One drone can cover up to 18 hectares of sunflower farmlands in only one hour.

There are some clear conditions for adoption of drones:

  1. High value crops with high profitability (e.g. sunflowers).

  2. Unfavorable operating conditions for traditional farm machinery due to weather, crop growth stage etc.

  3. Lack of access to efficient farm machinery due to infrastructure or capital cost needs.

  4. Rapid response times required.

Acumen, climate and smallholder farmers

I have been a fan of Jaqueline Novogratz and the work done by Acumen over the last few years. It is great to see Acumen close a $ 58 million impact fund, which is one of the first to drive climate adaptation for smallholder farmers.

Poverty, climate change, and resilient agriculture are intrinsically linked: More than half of the people living in poverty are smallholder farmers. These farmers provide a third of the world’s food supply. In Africa, their role is even larger as they produce approximately 80% of the continent’s food. Soil degradation, severe storms, shifting weather patterns, and more have changed the nature of farming, threatening farmers’ livelihoods and their ability to feed communities worldwide. These challenges are intensified by structural inefficiencies and limited access to credit. By supporting agribusinesses that offer aggregation, digital platforms, and financial solutions to smallholder farmers, ARAF seeks to build an ecosystem that enables farmers to raise their incomes and increase their resilience.

So, what do you think?

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 Lark, T.J., Spawn, S.A., Bougie, M. et al. Cropland expansion in the United States produces marginal yields at high costs to wildlife. Nat Commun 11, 4295 (2020). https://doi.org/10.1038/s41467-020-18045-z