Science - USA (2021-12-10)

reservoir in human-modified landscapes and
should be conserved ( 17 ). This will also lead to
greater connectivity for plants and animals in
fragmented, human-modified landscapes.
Although SFs show, on average, a rapid re-
covery, there is also substantial variation across
the study region (see credibility intervals in
Fig. 3), which indicates that some areas may
show arrested succession because of a lack of
seed sources or dominance of invasive grass,
ferns, or woody species. Under such condi-
tions, management practices for assisted natu-
ral regeneration—such as weeding, controlling
invasive species, enrichment planting, and
the establishment of ecological corridors—are
needed to safeguard multidimensional recovery.
Given the local and global importance of SFs
and their substantial R20y(on average, 78%;
range, 33 to 100%; Fig. 3B), we urge the em-
brace of SFs as a low-cost, nature-based solu-
tion to meet the United Nations’Sustainable
Development goals and the United Nations’
Decade on Ecosystem Restoration goals ( 42 ).
Enabling policies combined with careful land-
scape planning should identify areas where
SFs are best conserved and provide the most
co-benefits while minimizing socioecological
conflicts [e.g., ( 3 , 4 )]. SFs should feature pro-
minently in restoration portfolios, where older
SFs and OGFs are conserved, severely de-
graded areas are actively restored, and young
regrowth is protected from deforestation. For
example, SFs can only deliver their full con-
servation potential if they are conserved for
a sufficient amount of time, such that tree
species can attain reproductive maturity and
maintain viable populations ( 43 ). In addition,
substantial gains are made when young,
20-year-old SFs are conserved for 20 years
more, because AGB, SR, and similarity with
OGFs increase by 15 to 22% (fig. S1C). All OGFs
should be conserved because little remains;
they harbor many distinctive OGF species and
provide seed sources and dispersers to assure
landscape resilience ( 17 , 40 ). To monitor pas-
sive and active restoration success, we re-
commend using simple indicators in different
phases of succession, in which SH can be used
for the first 25 years (Fig. 3D) and Dmax and SR
in the following 25 years.

Conclusions

Our analysis shows that tropical forests and
theirsoilsarehighlyresilientbecauseallat-
tributes recover within 12 decades after low- to
moderate-intensity land use. Recovery of soil
attributes (<1 decade) and plant functional at-
tributes (<2.5 decades) is very fast, followed by
recovery of structure and diversity (2.5 to 6 dec-
ades), and recovery of AGB and SC is slowest
(12 decades). Network analysis shows that re-
covery is multidimensional, with three clus-
ters of attributes related to structure, SR, and
SC. Monitoring of forest restoration could use

Dmax, SH, and SR as complementary indica-

tors of multidimensional recovery.

REFERENCES AND NOTES

1. Food and Agricultural Organization of the United Nations
   (FAO),“Global forest resources assessment 2020–
   Key findings”(FAO, 2020).


2. R. L. Chazdonet al.,Sci. Adv. 2 , e1501639 (2016).


3. P. H. S. Brancalionet al.,Sci. Adv. 5 , eaav3223 (2019).


4. B. B. N. Strassburget al.,Nat. Ecol. Evol. 3 , 62– 70
   (2019).


5. S. Carpenter, B. Walker, J. M. Anderies, N. Abel,Ecosystems 4 ,
   765 – 781 (2001).


6. S. L. Pimm,Nature 307 , 321–326 (1984).


7. B. Ayala-Orozcoet al.,Land Degrad. Dev. 29 , 315– 325
   (2018).


8. J. P. Grime,Plant Strategies, Vegetation Processes, and
   Ecosystem Properties(Wiley, 2006).


9. N. Nordenet al.,Proc. Natl. Acad. Sci. U.S.A. 112 , 8013– 8018
   (2015).


10. D. Tilman,Plant Strategies and the Dynamics and Structure of
    Plant Communities(Monographs in Population Biology,
    Princeton Univ. Press, 1988).


11. J. H. Connell,Science 199 , 1302–1310 (1978).


12. C. D. Oliver, B. C. Larson,Forest Stand Dynamics: Updated
    Edition(Wiley, 1996).


13. L. R. Walker, D. A. Wardle, R. D. Bardgett, B. D. Clarkson,
    J. Ecol. 98 , 725–736 (2010).


14. R. L. Chazdon,Second Growth: The Promise of Tropical Forest
    Regeneration in an Age of Deforestation(Univ. Chicago
    Press, 2014).


15. M. Geiet al.,Nat. Ecol. Evol. 2 , 1104–1111 (2018).


16. L. Poorteret al.,Nature 530 , 211–214 (2016).


17. D. M. A. Rozendaalet al.,Sci. Adv. 5 , eaau3114 (2019).


18. See supplementary materials.


19. E. Veldkamp, M. Schmidt, J. S. Powers, M. D. Corre,Nat. Rev.
    Earth Environ. 1 , 590–605 (2020).


20. P. A. Martin, A. C. Newton, J. M. Bullock,Proc. Biol. Sci. 280 ,
    20132236 (2013).


21. P. H. Nye, D. J. Greenland,The Soil Under Shifting Cultivation
    (Technical Communication No. 51, Commonwealth Agricultural
    Bureau, 1960).


22. L. Poorter, M. van de Plassche, S. Willems, R. G. A. Boot,Plant
    Biol. 6 , 746–754 (2004).


23. S. A. Battermanet al.,Nature 502 , 224–227 (2013).


24. L. Poorteret al.,Nat. Ecol. Evol. 3 , 928–934 (2019).


25. B. Finegan,Trends Ecol. Evol. 11 , 119–124 (1996).


26. M. F. Barroset al.,For. Ecol. Manage. 482 , 118881 (2021).


27. M. Lohbeck, L. Poorter, M. Martínez-Ramos, F. Bongers,
    Ecology 96 , 1242–1252 (2015).


28. J. W. F. Sliket al.,Glob. Ecol. Biogeogr. 22 , 1261– 1271
    (2013).


29. F. Bongers, L. Poorter, W. D. Hawthorne, D. Sheil,Ecol. Lett. 12 ,
    798 – 805 (2009).


30. E. A. Johnson, K. Miyanishi,Ecol. Lett. 11 , 419–431 (2008).


31. E. Lebrija-Trejos, J. A. Meave, L. Poorter, E. A. Pérez-García,
    F. Bongers,Perspect. Plant Ecol. Evol. Syst. 12 , 267– 275
    (2010).


32. R. L. Chazdonet al.,Philos. Trans. R. Soc. London Ser. B 362 ,
    273 – 289 (2007).


33. G. Yarranton, R. Morrison,J. Ecol. 62 , 417–428 (1974).


34. A. E. N’Guessanet al.,For. Ecol. Manage. 433 , 325– 331
    (2019).


35. A. D. Manning, J. Fischer, D. B. Lindenmayer,Biol. Conserv. 132 ,
    311 – 321 (2006).


36. T. H. Oliveret al.,Trends Ecol. Evol. 30 , 673–684 (2015).


37. T. Juckeret al.,Glob. Change Biol. 23 , 177–190 (2017).


38. B. Sakschewskiet al.,Nat. Clim. Change 6 , 1032– 1036
    (2016).


39. C. C. Jakovac, M. Peña-Claros, T. W. Kuyper, F. Bongers,
    J. Ecol. 103 , 67–77 (2015).


40. V. Arroyo-Rodríguezet al.,Biol. Rev. Camb. Philos. Soc. 92 ,
    326 – 340 (2017).


41. L. Poorteret al.,Glob. Ecol. Biogeogr. 26 , 1423– 1434
    (2017).


42. UN Environment Assembly (UNEA),“Resolution 73/284:
    United Nations Decade on Ecosystem Restoration
    (2021–2030)”(UNEA, 2019); https://undocs.org/A/RES/73/
    284.


43. M. van Breugelet al.,PLOS ONE 8 , e82433 (2013).


44. D. Craven, dylancraven/MultiDimensional Recovery, Zenodo
    (2021); https://doi.org/10.5281/zenodo.4988848.

ACKNOWLEDGMENTS

This paper is a product of the 2ndFOR collaborative research

network on SFs (www.2ndFOR.org) and the sDiv working group

sUCCESS and is paper no. 7 of 2ndFOR. We thank the owners of

the SF sites for access to their forests, all the people who have

established and measured the plots, the institutions and funding

agencies that supported them (see below), and M. Aide for data

use.Funding:This research was supported by European Research

Council-ERC (Advanced Grant PANTROP 834775 to L.P.); German

Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig

(sDIV W7.20 sUCCESS to L.P., N.R., and M.v.B.) funded inter alia by the

Deutsche Forschungsgemeinschaft (DFG; FZT-118); Netherlands

Organisation for Scientific Research - NWO (ALW.OP241 to L.P., M.T.v.

d.S., and C.C.J.; ALWOP.457 to F.B. and R.Mu.; ALW 863.15.017 to

M.L.; and Veni.192.027 to M.T.v.d.S.); NWO-Fundação de Amparo á

Pesquisa do Estado de São Paulo 17418 (NEWFOR) to P.H.B., F.B., and

M.P.-C.; Agencia Nacional de Investigación y Desarrollo (FONDECYT

Regular No. 1201347) to D.C.; Conselho Nacional de Desenvolvimento

Científico e Tecnológico-CNPq (to A.C.F., I.C.G.V.; 308471/2017-2

to M.M.E.-S.; 308877/2019-5 to Y.R.F.N.; #312178/2019-0 to B.A.S.;

CNPq 308778-2017-0 to I.C.G.V.; CNPq to G.W.F.; Universal 01/2016 to

H.M.T.; 309659/2019-1 to S.C.M.; and SinBiose-REGENERA 442371/

2019-5 to C.C.J. and R.Me.); Corredor Biológico La Gamba

(COBIGA) to F.O.; Deutsche Forschungsgemeinschaft DFG (RU

1536/3-1 to N.R.); Fondo Mixto CONACYT-Gobierno del estado de

Yucatán (FOMIX YUC-2008-C06-108863 to J.M.D. and J.L.H.-S.);

Fundacão de Amparo à Pesquisa de Minas Gerais-FAPEMIG (to G.W.F.;

PPM-00627-16 to Y.R.F.N.; PPM-00726-16 to M.M.E.-S.; PPM-00623-16

to M.D.M.V.; and APQ-03348-16 to H.M.T.); Fundação de Amparo à

Pesquisa do Estado do Rio Grande do Sul-FAPERGS (2218–2551/ 12-2

to S.C.M.); Fundación Jardín Botánico de Medellín to A.I.; GEF/FONACIT

to P.M.V.; German Centre for Integrative Biodiversity Research (iDiv)

Halle-Jena-Leipzig, a research center of the German Research

Foundation (DFG–FZT 118) (iDiv-Flexpool grant nos. 34600967 and

34600970 to N.R. and S.K.); Herbario JAUM to A.I.; Rainforest

Luxemburg to F.O.; Secretaría de Educación Pública-Consejo Nacional

de Ciencia y Tecnología, Ciencia Básica (SEP-CONACYT 2015-255544

to P.B. and F.M.); Stichting Het Kronendak to H.M.T. and H.F.M.V.;

STRI, ForestGEO, Heising–Simons Foundation, HSBC Climate

Partnership, Stanley Motta, Small World Institute Fund, the Hoch family,

to J.S.H. and M.v.B.; Universidad de Antioquia to J.J.-M., Universidad

Nacional Autónoma de México, Programa de Apoyo a Proyectos de

Investigación e Innovación Tecnológica (DPAGA–PAPIIT IN218416,

DPAGA–PAPIIT IN217620 to J.A.M., E.A.P.-G. and R.Mu.; PAPIIT-UNAM

IN211417 to P.B. and F.M.); Rufford Small Grants 19426-2 to F.M.;

SENACYT Panama Grant (COL10-052) to D.H.D.; Tropenbos

Foundation to H.F.M.V.; US National Science Foundation (no. 9208031

to D.H.D. and S.J.D.; EAR-1360391 to M.v.B.; and Graduate Fellowship to

S.G.L.); Wageningen University and Research Interdisciplinary Research

and Education Fund (FOREFRONT program) to F.B. and H.M.T.; and

Yale-NUS College and MOE (through a startup grant and grant IG16-

LR004) to M.v.B. A.H.-J. was supported by the LICCI project, funded by

the European Research Council (FP7-771056-LICCI). This work

contributes to the“María de Maeztu”Programme for Units of

Excellence of the Spanish Ministry of Science and Innovation (CEX2019-

000940-M).Author contributions: L.P., B.H., D.C., C.C.J., M.T.v.d.S.,

L.A., F.B., C.E.F., R.L.C., S.K., J.A.M., R.Mu., N.N., N.R., and

M.v.B. conceived the idea; all authors but C.E.F., S.K., and N.R.

contributed data; B.H., D.C., C.C.J., M.T.v.d.S., and L.P. analyzed the

data; L.P. led the writing of the manuscript with the help of B.H.,

D.C., C.C.J., and M.T.v.d.S.; L.A., F.B., C.E.F., R.L.C., S.K., J.A.M., R.Mu.,

N.N., N.R., M.v.B., A.M.A.Z., B.A., J.L.A., P.B., P.H.S.B., E.N.B.,

H.d.F., D.H.D., G.D., S.J.D., J.M.D., S.M.D., A.C.F., C.E.F., B.F., A.H.-J.,

J.L.H.-S., P.H., A.H.-J., J.K., S.G.L., M.L., R.L.-C., M.M.-R., F.P.L.M.,

F.M., S.C.M., A.E.N., F.O., E.O.-M., E.A.P.-G., B.X.P., D.P., J.S.P.,

S.R.-B., D.M.A.R., J.R., M.T., H.M.T., E.V.d.S.B.S., H.F.M.V., H.v.d.W.,

P.M.V., and G.W.F. commented upon the results and the manuscript;

and all authors approved submission of the manuscript.Competing

interests:The authors declare no competing interests.Data and

materials availability:Data on relative recovery of 12 attributes and

the code are available at Zenodo ( 44 ).

SUPPLEMENTARY MATERIALS

science.org/doi/10.1126/science.abh3629

Materials and Methods

Supplementary Text

Figs. S1 to S5

Tables S1 to S3

References ( 45 Ð 70 )

10 March 2021; accepted 6 October 2021

10.1126/science.abh3629

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