and Ultisols, the majority of P is associated with or precipitated by secondary soil minerals e.g.
The two main soil types in Emusutswi are humic nitosols and ferralsols
and Nyabeda and Nyalgunga have ferralsols
and acrisols (Gachene and Kimaru, 2003).
Soil profiles derived from I-type granites were classified as eutric Regosols (dry and sub-humid zone) and hypereutric chromic lixisols (humid zone), whereas those developed from S-type granites were classified as eutric regosols (dry zone), dystric regosols (sub-humid zone) and dystric xanthic ferralsols
(humid zone) according to the World Reference Base for Soil Resources (IUSS Working Group WRB, 2014).
The soil was classified as a clay loam Ferralsols
Attributes Details of Studied District Representing Agro-ecological Zones Agroecological zone West Nile District Moyo Location 03[degrees]39N 31[degrees]43,E Geographical location North Western Uganda Land area ([km.sup.2]) 2,059 Altitude (masl) 900-1,500 History District formed in 1956 Major geological formations Gneiss, alluvial deposits, & schist, quartzite & marble Major soil types Vertisols, Leptosols, alluvial deposits & Ferralsols
Economic activities Subsistence agriculture Rainfall (mm) 1,500-1,700 Rainfall patterns March-June; August-November Dry season Late November to early March Min.
Eutric NITISOLS: with nito-chromic CAMBISOLS and chromic ACRISOLS and LUVISOLS, partly lithic, pisoferric or petroferric phase UM 4 LB1 Well drained, very deep, dark red, very friable clay: Nito-rhodic FERRALSOLS
. Table 3: Coordinates of data collection points for all the AEZs.
Se encontraron 19 Grupos de suelos, la superficie ocupada por cada grupo en porcentaje con respecto a la superficie total del estado (2 466 100 ha), en orden decreciente fueron: Gleysols (20.5 %), Histosols (13.4 %), Fluvisols (10.4 %), Acrisols (9.73 %), Vertisols (7.48 %), Leptosols (7.07 %), Alisols (6.97 %), Luvisols (6.49 %), Cambisols (5.77 %), Arenosols (2.1 %), Lixisols (1.56 %), Solonchaks (1.6 %), Calcisols (0.83 %), Nitisols (0.39 %), Ferralsols
(0.29 %), Plintosols (0.06 %), Tecnosols (0.04 %), Phaeozems (0.03 %) y Regosols (0.03 %) (Figura 1).
Carbon accumulation at depth in Ferralsols
under zero-till subtropical agriculture.
In Nova Olinda do Norte, the dominant vegetation is classified as evergreen lowland tropical moist forest and the predominant soils are Xanthic Ferralsols
(allic yellow latosol in the Brazilian system), which are heavily weathered, acidic, and very poor in nutrients such as P, Ca, and K.
are the predominant soil type, in which Xanthic Ferralsols
dominate the 1 000-1 800 m altitudinal zones, and Rhodic Ferralsols
are dominant below 1 000 m altitudinal zones (Tran 1991, Vo et al.
The site is on gentle slope (<10%); the soils are deep, well-drained, mostly stone-free, and high in ferralsols
, acrisols, and nitosols, with site index of 20 m at 25 years for Pinus kesiya .
Soil types include mostly Humic Acrisols and Plinthic Ferralsols
(accounting for around 80% of the total area), Rhodic Ferralsols
, Lithic Leptosols, and Eutric Fluvisols.