Root biomass, turnover and net primary productivity of a coffee agroforestry system in Costa Rica: effects of soil depth, shade trees, distance to row and coffee age

被引：40

作者：

Defrenet, Elsa ^{[1
,2
]}

Roupsard, Olivier ^{[1
,2
]}

Van den Meersche, Karel ^{[1
,2
]}

Charbonnier, Fabien ^{[1
,3
,4
]}

Pastor Perez-Molina, Junior ^{[2
]}

Khac, Emmanuelle ^{[1
]}

Prieto, Ivan ^{[5
]}

Stokes, Alexia ^{[6
]}

Roumet, Catherine ^{[5
]}

Rapidel, Bruno ^{[2
,7
]}

Virginio Filho, Elias de Melo ^{[2
]}

Vargas, Victor J. ^{[8
]}

Robelo, Diego ^{[5
]}

Barquero, Alejandra ^{[9
]}

Jourdan, Christophe ^{[1
]}

机构：

[1] CIRAD, UMR Eco & Sols Ecol Fonct & Biogeochim Sols & Agr, 2 Pl Viala, F-34060 Montpellier 2, France

[2] CATIE Trop Agr Ctr Res & Higher Educ, Turrialba 7170, Costa Rica

[3] El Colegio Frontera Sur, Dept Agr Sociedad & Ambiente, Unidad San Cristobal Casas, Chiapas, Mexico

[4] Consejo Nacl Ciencia & Technol, Mexico City, DF, Mexico

[5] Univ Montpellier 3, Univ Montpellier, CNRS, CEFE,UMR 5175,EPHE, 1919 Route Mende, F-34293 Montpellier 5, France

[6] INRA Bot & Bioinformat Architecture Plantes AMAP, Bd Lironde,TA A-51-PS2, F-34398 Montpellier 5, France

[7] CIRAD, UMR, SYSTEM, 2 Pl Viala, Montpellier, France

[8] CICAFE, Unidad Invest, ICAFE Prod Sostenible, Heredia, Costa Rica

[9] Cafetalera Aquiares SA, POB 362-7150, Turrialba, Costa Rica

来源：

ANNALS OF BOTANY | 2016年 / 118卷 / 04期

关键词：

Allometry; sequential coring; fine root decomposition; NPP; agroforestry; growth rings; Coffea arabica; Erythrina poeppigiana; BELOW-GROUND BIOMASS; LITTER DECOMPOSITION; ORGANIC-MATTER; ARABICA L; NITROGEN AVAILABILITY; SEASONAL-VARIATION; FOREST ECOSYSTEMS; FINE ROOTS; DYNAMICS; EUCALYPTUS;

D O I：

10.1093/aob/mcw153

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

Background and Aims In Costa Rica, coffee (Coffea arabica) plants are often grown in agroforests. However, it is not known if shade-inducing trees reduce coffee plant biomass through root competition, and hence alter overall net primary productivity (NPP). We estimated biomass and NPP at the stand level, taking into account deep roots and the position of plants with regard to trees. Methods Stem growth and root biomass, turnover and decomposition were measured in mixed coffee/tree (Erythrina poeppigiana) plantations. Growth ring width and number at the stem base were estimated along with stem basal area on a range of plant sizes. Root biomass and fine root density were measured in trenches to a depth of 4 m. To take into account the below-ground heterogeneity of the agroforestry system, fine root turnover was measured by sequential soil coring (to a depth of 30 cm) over 1 year and at different locations (in full sun or under trees and in rows/inter-rows). Allometric relationships were used to calculate NPP of perennial components, which was then scaled up to the stand level. Key Results Annual ring width at the stem base increased up to 2.5 mm yr(-1) with plant age (over a 44-year period). Nearly all (92 %) coffee root biomass was located in the top 1.5 m, and only 8 % from 1.5 m to a depth of 4 m. Perennial woody root biomass was 16 t ha(-1) and NPP of perennial roots was 1.3 t ha(-1) yr(-1). Fine root biomass (0-30 cm) was two-fold higher in the row compared with between rows. Fine root biomass was 2.29 t ha(-1) (12 % of total root biomass) and NPP of fine roots was 2.96 t ha(-1) yr(-1) (69 % of total root NPP). Fine root turnover was 1.3 yr(-1) and lifespan was 0.8 years. Conclusions Coffee root systems comprised 49 % of the total plant biomass; such a high ratio is possibly a consequence of shoot pruning. There was no significant effect of trees on coffee fine root biomass, suggesting that coffee root systems are very competitive in the topsoil.

引用

页码：833 / 851

页数：19