Hijbeek (2026). Targeting yield constraints with soil carbon

Rapid #: -27738196

CROSS REF ID:

36824701190001865

LENDER:

KWC (University of the Cumberlands) :: Main Library

BORROWER:

ORE (Oregon State University) :: Main Library

TYPE:

Article CC:CCG

JOURNAL TITLE:

Nature food

USER JOURNAL TITLE:

Nature Food

ARTICLE TITLE:

Targeting yield constraints with soil carbon

ARTICLE AUTHOR:

Hijbeek, Renske

VOLUME:

7

ISSUE:

8

MONTH:

YEAR:

2026-08

PAGES:

742 - 743

ISSN:

2662-1355

OCLC #:

Processed by RapidX:

10/20/2026 7:34:13 AM

This material may be protected by copyright law (Title 17 U.S. Code)

|

|

|

User Name: =

Date and Time: = 2026-10-20

Job Number: = 299358327

Documents (1)

Client/Matter:

-None-

Search Terms:

Targeting yield constraints with soil carbon

Search Type:

NaturalAnd

Content Type

Narrowed by

news

-None-

1. Targeting yield constraints with soil carbon

Page 1 of 3

Targeting yield constraints with soil carbon

Targeting yield constraints with soil carbon

Nature Food

August 2026

Section: Pg. 742-743; Vol. 7; No. 8; ISSN: 2662-1355

Length: 1062 words

Byline: Renske Hijbeek;

11

Body

Yield benefits of increasing soil carbon observed in field trials are much less present on farmers’ fields.
Disentangling when and where soil organic matter functions address yield-limiting factors will allow the best use of
our organic resources.

It is obvious, is it not? Soil organic carbon (SOC) is a key indicator for soil fertility in all of its three dimensions. It
improves soil structure, enhances nutrient supply and supports soil biota functioning. Therefore, increasing SOC
should surely lead to higher crop yields. Indeed, fertile soils with good production capacities often — but not
always — have relatively high carbon content. As such, especially in the international policy arena, increasing SOC
is promoted as a means to improve the fertility of agricultural soils.

Perhaps, somewhat counter-intuitively, Zhao et al.1 report in Nature Food that benefits of SOC for maize yields
observed in field trials do not translate to real-world farms in northeast China. Across experimental trials (n =
1,246), maize yields increased 8–13% along a gradient of SOC up to a threshold of 30–40 g SOC per kg soil. By
contrast, on farmers’ fields (n = 192), maize yields only increased 5% up to a threshold of 10 g SOC per kg soil.
With SOC content above this latter value, maize yields decreased again to around initial yields in farmers’ fields.

These findings align well with earlier research in Europe2, where weak associations were found between SOC and
crop yields on farms across six countries (n = 1,264). Both studies raise the question as to which yield-limiting
factors are present on farms compared with field trials, and the extent to which SOC can mitigate these
constraints.

Zhao et al.1 suggest that the difference in nitrogen (N) application rates between field trials (151 kg N

ha−1)

and

farmers’ fields (225 kg N

ha−1)

is one cause of the discrepancy in observed benefits. With maize yields around 10 t

ha−1,

one can indeed question whether applying 151 kg N

ha−1

is sufficient. Assuming an N concentration of

around 2%, N offtake in the grains will be around 200 kg

ha−1.

No wonder soils with more SOC and therefore

higher N mineralization rates provided better crop yields. Moreover, with higher phosphorus and potassium
application, the relationship between SOC and maize yields in field trials approached the one observed on farmers’
fields.

1

Plant Production Systems group, Wageningen University and Research, Wageningen, , the Netherlands, 0000 0001 0791

5666, grid.4818.5,

https://ror.org/04qw24q55

renske.hijbeek@wur.nl

Page 2 of 3

Targeting yield constraints with soil carbon

A more pertinent question is whether supplying nutrients by building up soil organic matter, followed by
decomposition, is the most environmentally smart way of farming, compared with directly supplying nutrients in the
growing season. Especially for N, which is highly mobile and prone to losses to the surrounding environment.

Notwithstanding the lack of translation into yield benefits, increasing SOC improves soil functioning, but apparently
the  factors  improved  in  farmers’  fields  were  not  the  growth-limiting  ones3.  With  competing  claims  on  the  use  of
biomass resources (for example, biogas production or animal feed) when returning organic materials to soils, the
materials need to be directed to the soils that need them most. The study by Zhao et al.1 shows that fields with a
low  (less  than  approximately  20%)  or  a  high  (more  than  approximately  35%)  clay  content  are  the  most  likely  to
benefit.  For  such  soils,  increasing  soil  carbon  apparently  is  more  likely  to  alleviate  yield-limiting  factors.  In  a
similar vein, when asked if they perceived a deficiency in soil organic matter for crop production, European farmers
indicated that this was especially the case when cultivating crops under more extreme conditions4. Aside from soil
texture,  factors  such  as  field  slope,  climate  (either  very  dry  or  wet)  and  cultivation  of  specialized  or  horticultural
crops were relevant according to the European farmers.

A second explanation provided by the authors why benefits observed in field trials do not translate to real farms is
the  sub-optimal  implementation  of  soil  conservation  practices  (such  as  returning  residues  when  implementing  no
tillage or manure management) on farms compared with field trials. Indeed, farmers sometimes struggle with time
planning  and  logistics  to  include  conservation  practices,  especially  during  field  preparations5.  Yet,  the  benefits  of
soil carbon for crop yields cannot be assessed in isolation, they always depend on the agro-ecological conditions,
practices used to increase soil carbon6 and complementary farm management (Fig. 1). Already in the 1990s, yield
benefits  of  SOC  were  related  to  an  intensification  gradient,  with  more  extensive  farms  benefiting  the  most  and
intensive  farms  the  least,  as  technical  replacements  such  as  external  nutrient  inputs,  irrigation,  (non-inversion)
tillage and pest and disease control are more easily available within more intensive farming systems7.

Fig. 1

Yield benefits of soil organic matter depend on agro-ecological conditions and farming systems.

Boxes with dashed lines indicate soil organic matter functions for crop production. Dashed arrows show potential
replacement or complement with technical management options, namely irrigation, external nutrient inputs, (non-
inversion) tillage, and chemical or biological pest and disease control7. Potentials for replacement depend on agro-
ecological conditions (for example, soil texture and climate) and crops cultivated1,4. N, nitrogen; P, phosphorus; K,
potassium.

Ideally then, soil organic matter functions and technical options complement each other, in ways that ensure crops
thrive most and environmental impacts are lowest. Given the diversity of agro-ecological conditions and farming
systems, global or continental soil carbon thresholds8,9 will have little practical meaning for farmers, as shown by
Zhao et al1. At global scales, latitude and related climate is a major driver of SOC content. While reaching 2% SOC
content in the upper layer of tropical soils might be nearly impossible, most boreal soils are already above such a
value. At local scales, current yield limitations will determine whether increasing SOC will benefit crop yields and
how. Disentangling the contexts in which soil organic matter functions complement technical options can provide
guidance on how to make the best use of our organic resources.

Acknowledgements

I thank K. Descheemaeker and K. Giller (Wageningen University and Research) for reading a draft version and the
useful suggestions.

Bibliography

[1].Zhao, S. Nat. Food (2026).

Page 3 of 3

Targeting yield constraints with soil carbon

[2].Vonk, WJ. Nutr. Cycl. Agroecosyst. (2020). Vol. 118. Pg 325-334.

[3].Janssen, B. H. Organic matter and soil fertility. Syllabus, Wageningen Agricultural University (2002).

[4].Hijbeek, R. Ecol. Indic. (2017). Vol. 83. Pg 390-403.

[5].Morant, MV. Eur. J. Agron. (2026). Vol. 172.

[6].Moinet, GYK. Hijbeek, R. van Vuuren, DP. Giller, KE. Glob. Change Biol. (2023). Vol. 29. Pg 2384-2398.

[7].van Noordwijk, M. Cerri, C. Woomer, PL. Nugroho, K. Bernoux, M. Geoderma (1997). Vol. 79. Pg 187-225.

[8].Ma, Y. Nat. Geosci. (2023). Vol. 16. Pg 1159-1165.

[9].Oldfield, EE. Bradford, MA. Wood, SA. Soil (2019). Vol. 5. Pg 15-32.

Classification

Language: ENGLISH

Publication-Type: Magazine

Journal Code: 43016

Subject: SOIL HEALTH (92%); SOIL CONSERVATION (90%); CORN FARMING (90%); CROP PRODUCTION
(89%); CROP RESEARCH (89%); AGRICULTURE (78%); MANUFACTURING OUTPUT (76%);
INTERNATIONAL RELATIONS & NATIONAL SECURITY (74%); SOIL HEALTH (93%); INTERNATIONAL
RELATIONS & NATIONAL SECURITY (75%); MANUFACTURING OUTPUT (76%); SOIL CONSERVATION
(90%); CROP RESEARCH (90%)

Organization: Plant Production Systems group; Wageningen University and Research

Industry: SOIL HEALTH (93%); MANUFACTURING OUTPUT (76%); CORN FARMING (90%); AGRICULTURE
(78%); CROP PRODUCTION (89%); CROP RESEARCH (90%)

Geographic: NORTHEAST CHINA (56%); NORTHEAST CHINA (56%); CHINA (76%); EUROPE (69%);
EUROPE (74%); CHINA (79%)

Load-Date: August 20, 2026

End of Document

Hijbeek (2026). Targeting yield constraints with soil carbon

Page 1

Page 2

Page 3

Page 4

Page 5

Document Outline