The hydrological and soil impacts of forestation in the tropics

Scott, David F.; Bruijnzeel, L. A.; Mackensen, Jens

doi:10.1017/cbo9780511535666.032

Cited by 76 publications

(124 citation statements)

References 113 publications

(171 reference statements)

Supporting

Mentioning

120

Contrasting

Unclassified

Order By: Relevance

“…FAO, 2005;Bradshaw et al, 2007;Van Dijk et al, 2009) whereas the effect of forestation on tropical dry-season flows is also under debate (Calder, 2005;Scott et al, 2005). The general contention is that the net effect of an increase in forest cover on dryseason flow depends on the "trade-off" between increases in Q due to enhanced soil water recharge on the one hand (as forestation generally increases soil macro-porosity and infiltration characteristics; Ilstedt et al, 2007;Bonell et al, 2010;Zimmermann et al, 2006Zimmermann et al, , 2010Hassler et al, 2011), and decreases in soil water reserves and Q on the other hand due to the higher water use of trees compared to crops, pasture, or scrubs (Bruijnzeel, 1989(Bruijnzeel, , 2004Jackson et al, 2005;Scott et al, 2005). Reviews of micro-scale (< 1 km 2 ) experimental catchment studies (e.g.…”

Section: H E Beck Et Almentioning

confidence: 99%

“…Chandler and Walter, 1998;Zhou et al, 2002;Zhang et al, 2004) should be large enough to overcome the associated increases in forest water use (Chandler, 2006;cf. Bruijnzeel, 2004;Scott et al, 2005;Zhou et al, 2010). Indeed, as long-term Q records for large, once degraded catchment areas are becoming available, evidence of improved baseflows (Q bf ) following large-scale land rehabilitation is beginning to be documented (Wilcox and Huang, 2010;Zhou et al, 2010).…”

Section: H E Beck Et Almentioning

confidence: 99%

“…Chandler and Walter, 1998;Zhou et al, 2002). The direction and magnitude of the change in Q bf will depend on the trade-off between the changes in vegetation water use and infiltration associated with forest regeneration (Bruijnzeel, 1989;Scott et al, 2005).…”

Section: H E Beck Et Almentioning

confidence: 99%

“…If true, this would imply that in the investigated catchments the increase in Q due to enhanced rainfall infiltration during forest regrowth overrides the decrease in Q associated with the greater water use of the aggrading forests (cf. Bruijnzeel, 1989;Scott et al, 2005). The soils beneath young secondary forests in Puerto Rico show higher bulk density than beneath mature secondary forests (Weaver et al, 1987;Lugo and Scatena, 1995) and are less structured (Lugo and Helmer, 2004).…”

Section: Impacts Of Land-cover Change On Streamflowsmentioning

confidence: 99%

“…Table 6), although demonstrated decreases in the amounts of headwater-or hillslope stormflow generation after reforesting severely degraded land (Chandler and 1998; Zhou et al, 2002;Zhang et al, 2004;Sun et al, 2006) must be considered large enough to overcome the associated increases in forest water use (Chandler, 2006;cf. Bruijnzeel, 2004;Scott et al, 2005). Nevertheless, long-term Q data for large, once degraded but subsequently rehabilitated catchments in sub-humid Texas (Wilcox and Huang, 2010) and the humid Red Soils region of southern China (Zhou et al, 2010) have recently indicated gradually increased Q bf over prolonged periods of time following large-scale land rehabilitation and regreening, suggesting soil improvement to be the dominant factor in these cases.…”

Section: Impacts Of Land-cover Change On Streamflowsmentioning

confidence: 99%

See 4 more Smart Citations

The impact of forest regeneration on streamflow in 12 mesoscale humid tropical catchments

Beck

Bruijnzeel

Dijk

et al. 2013

Hydrol. Earth Syst. Sci.

Self Cite

106

View full text Add to dashboard Cite

Abstract. Although regenerating forests make up an increasingly large portion of humid tropical landscapes, little is known of their water use and effects on streamflow (Q). Since the 1950s the island of Puerto Rico has experienced widespread abandonment of pastures and agricultural lands, followed by forest regeneration. This paper examines the possible impacts of these secondary forests on several Q characteristics for 12 mesoscale catchments (23-346 km 2 ; mean precipitation 1720-3422 mm yr −1 ) with long (33-51 yr) and simultaneous records for Q, precipitation (P ), potential evaporation (PET), and land cover. A simple spatially-lumped, conceptual rainfall-runoff model that uses daily P and PET time series as inputs (HBV-light) was used to simulate Q for each catchment. Annual time series of observed and simulated values of four Q characteristics were calculated. A least-squares trend was fitted through annual time series of the residual difference between observed and simulated time series of each Q characteristic. From this the total cumulative change (Â) was calculated, representing the change in each Q characteristic after controlling for climate variability and water storage carry-over effects between years. Negative values ofÂ were found for most catchments and Q characteristics, suggesting enhanced actual evaporation overall following forest regeneration. However, correlations between changes in urban or forest area and values ofÂ were insignificant (p ≥ 0.389) for all Q characteristics. This suggests there is no convincing evidence that changes in the chosen Q characteristics in these Puerto Rican catchments can be ascribed to changes in urban or forest area. The present results are in line with previous studies of mesoand macro-scale (sub-)tropical catchments, which generally found no significant change in Q that can be attributed to changes in forest cover. Possible explanations for the lack of a clear signal may include errors in the land cover, climate, Q, and/or catchment boundary data; changes in forest area occurring mainly in the less rainy lowlands; and heterogeneity in catchment response. Different results were obtained for different catchments, and using a smaller subset of catchments could have led to very different conclusions. This highlights the importance of including multiple catchments in land-cover impact analysis at the mesoscale.

show abstract

Section: H E Beck Et Almentioning

confidence: 99%

Section: H E Beck Et Almentioning

confidence: 99%

Section: H E Beck Et Almentioning

confidence: 99%

Section: Impacts Of Land-cover Change On Streamflowsmentioning

confidence: 99%

Section: Impacts Of Land-cover Change On Streamflowsmentioning

confidence: 99%

See 3 more Smart Citations

The impact of forest regeneration on streamflow in 12 mesoscale humid tropical catchments

Beck

Bruijnzeel

Dijk

et al. 2013

Hydrol. Earth Syst. Sci.

Self Cite

106

View full text Add to dashboard Cite

show abstract

Reforesting severely degraded grassland in the Lesser Himalaya of Nepal: Effects on soil hydraulic conductivity and overland flow production

Ghimire

Bonell

Bruijnzeel

et al. 2013

J. Geophys. Res. Earth Surf.

View full text Add to dashboard Cite

[1] Severely degraded hillslopes in the Lesser Himalaya challenge local communities as a result of the frequent occurrence of overland flow and erosion during the rainy season and water shortages during the dry season. Reforestation is often perceived as an effective way of restoring predisturbance hydrological conditions but heavy usage of reforested land in the region has been shown to hamper full recovery of soil hydraulic properties. This paper investigates the effect of reforestation and forest usage on field-saturated soil hydraulic conductivities (K fs ) near Dhulikhel, Central Nepal, by comparing degraded pasture, a footpath within the pasture, a 25 year old pine reforestation, and little disturbed natural forest. The hillslope hydrological implications of changes in K fs with land-cover change were assessed via comparisons with measured rainfall intensities over different durations. High surface and near-surface K fs in natural forest (82-232 mm h À1 ) rule out overland flow occurrence and favor vertical percolation. Conversely, corresponding K fs for degraded pasture (18-39 mm h À1 ) and footpath (12-26 mm h À1 ) were conducive to overland flow generation during medium-to high-intensity storms and thus to local flash flooding. Pertinently, surface and near-surface K fs in the heavily used pine forest remained similar to those for degraded pasture. Estimated monsoonal overland flow totals for degraded pasture, pine forest, and natural forest were 21.3%, 15.5%, and 2.5% of incident rainfall, respectively, reflecting the relative ranking of surface K fs . Along with high water use by the pines, this lack of recovery of soil hydraulic properties under pine reforestation is shown to be a critical factor in the regionally observed decline in base flows following large-scale planting of pines and has important implications for regional forest management.Citation: Ghimire, C. P., M. Bonell, L. A. Bruijnzeel, N. A. Coles, and M. W. Lubczynski (2013), Reforesting severely degraded grassland in the Lesser Himalaya of Nepal: Effects on soil hydraulic conductivity and overland flow production,

show abstract

Effect of land cover and use on dry season river runoff, runoff efficiency, and peak storm runoff in the seasonal tropics of Central Panama

et al. 2013

View full text Add to dashboard Cite

[1] A paired catchment methodology was used with more than 3 years of data to test whether forests increase base flow in the dry season, despite reduced annual runoff caused by evapotranspiration (the ''sponge-effect hypothesis''), and whether forests reduce maximum runoff rates and totals during storms. The three study catchments were : a 142.3 ha old secondary forest, a 175.6 ha mosaic of mixed age forest, pasture, and subsistence agriculture, and a 35.9 ha actively grazed pasture subcatchment of the mosaic catchment. The two larger catchments are adjacent, with similar morphology, soils, underlying geology, and rainfall. Annual water balances, peak runoff rates, runoff efficiencies, and dry season recessions show significant differences. Dry season runoff from the forested catchment receded more slowly than from the mosaic and pasture catchments. The runoff rate from the forest catchment was 1-50% greater than that from the similarly sized mosaic catchment at the end of the dry season. This observation supports the sponge-effect hypothesis. The pasture and mosaic catchment median runoff efficiencies were 2.7 and 1.8 times that of the forest catchment, respectively, and increased with total storm rainfall. Peak runoff rates from the pasture and mosaic catchments were 1.7 and 1.4 times those of the forest catchment, respectively. The forest catchment produced 35% less total runoff and smaller peak runoff rates during the flood of record in the Panama Canal Watershed. Flood peak reduction and increased streamflows through dry periods are important benefits relevant to watershed management, payment for ecosystem services, water-quality management, reservoir sedimentation, and fresh water security in the Panama Canal watershed and similar tropical landscapes.

show abstract

The hydrological and soil impacts of forestation in the tropics

Cited by 76 publications

References 113 publications

The impact of forest regeneration on streamflow in 12 mesoscale humid tropical catchments

The impact of forest regeneration on streamflow in 12 mesoscale humid tropical catchments

Reforesting severely degraded grassland in the Lesser Himalaya of Nepal: Effects on soil hydraulic conductivity and overland flow production

Effect of land cover and use on dry season river runoff, runoff efficiency, and peak storm runoff in the seasonal tropics of Central Panama

Contact Info

Product

Resources

About