Hydro‐Morphological Disturbance and Suitability for Temporary Agriculture of Riverine Islands in a Tropical Wandering River

Abstract

Fluvial islands can be found both in natural and regulated rivers, creating fuzzy interfaces among the river corridor functional zones (Gurnell et al., 2016), characterized by varying magnitudes of inundation and sediment dynamics. Their patterns are a useful tool to infer the river history, dynamics (

Modelling of alluvial soil quality and production in permanent banana Harton plantations

“…Chemical indicators. Chemical indicators are neutral to medium alkaline soils, low levels of OM and N, low to medium levels of P, medium levels of Ca and low levels of K + , Mg 2+ , and CEC, showing significant differences, except for OM and N. There are decreasing trends in the mean values of pH, P, K + , Ca 2+ , Mg 2+ and CEC in 15 years of permanent cultivation, this decrease does not represent a risk in the pH level, but in the levels of the other indicators, although, considering the physical characteristics (high % of sand, low in clay and low Rp) of the area, there is a potential risk of decrease in the main bases and OM, typical behaviours registered in these types of soils (Olivares et al 2022b;Serrao et al 2022), also described in the main classification studies on Entisols soils of the Peruvian Amazon (ONERN 1972;Rodríguez 1990).…”

“…In general, river corridors have great potential for agriculture with particular characteristics (Serrao et al 2022), slightly acidic to neutral pH, medium to high levels of exchangeable bases (Chinchilla et al 2011;Rajkishore et al 2017), rich in nutrients and variable organic matter (Rudorff et al 2014;Serrao et al 2022), therefore, banana is a species that adapts very well to this type of soil (Zurbrügg et al 2012;Rajkishore et al2017;Serrao et al 2022), and plantations after 5 years of permanent cultivation under monoculture still maintain commercially acceptable soil conditions and production. However, in 15 years (T1) there is a tendency for the main macronutrients to decrease, generated by the high risk of flood erosion that these types of soils present (Rajkishore et al 2017;Olivares et al 2022a), compromising soil quality and crop production.…”

“…(b) Negative impact on pH (P < 0.01), the R 2 shows that age contributes 80.07% of the pH variation (Table 5). This behaviour expresses an acidification process, although the pH remains at a neutral level, a typical condition for this type of soil (Uribe et al 2002;Olivares et al 2022a;Serrao et al 2022), however, the reduction of pH is associated with the loss of Ca and Mg (Bohn et al 1993;Rajkishore et al 2017;Florida & Acuña 2020), which can be observed in the results (Table 2) and is possibly responsible for the reduction in crop yield. (c) Negative impact (P < 0.01) on P levels, the R 2 evidence that age contributes 79.20% to P variation (Table 6).…”

“…In addition, this order is characterised by presenting a high proportion of sand, clay contents less than 20%, slightly acid to neutral pH, and medium to high levels of exchangeable bases in the surface stratum (Chinchilla et al 2011), conditions https://doi.org/10.17221/22/2023-SWR that favour cultivation. These fertility conditions occur due to the hydrological exchange between a river and its floodplain, which drive nutrient turnover seasonally and turn river floodplains into highly valuable ecosystems (Zurbrügg et al 2012), with significant concentrations of nutrients, sediments and variable organic matter (Rudorff et al 2014) and great potential for agricultural development, which so far has not received adequate attention despite their unique characteristics (Serrao et al 2022).…”

“…Plantain presents great adaptability capacity (Rajkishore et al 2017) and alluvial soils excellent conditions for this crop (Serrao et al 2022). However, studies suggest evaluating the productive status (Martínez et al 2022) through soil quality monitoring (Olivares et al 2020a), taking into account that alluvial soils periodically present danger of flood erosion (Rajkishore et al 2017), in addition, regardless of management Entisols soils present a high risk of degradation in tropical regions, due to their climate characteristics, low soil stability and nutrient loss by washing (Uribe et al 2002;Olivares et al 2022b), which can limit growth and productivity.…”