Effects of Forest Thinning on the Long-Term Runoff Changes of Coniferous Forest Plantation

Forests and water are closely related to each other. Thus, forest management is crucial for the sustainable clean water supply. Forest thinning is one of the fundamental forest management practices, as it can change runoff by controlling the density of trees. In this study, the effect of forest thinning on long-term runoff changes was evaluated, based on the long-term rainfall-runoff data of a coniferous plantation forest catchment in Korea. From the double mass curve and Pettitt’s test, a statistically significant increase in runoff rates was identified. A simple linear regression model of the double mass curve can successfully quantify the net effect of forest thinning on the runoff increase. Furthermore, it was also confirmed that forest thinning does not significantly increase the risk of flooding. About ten years after forest thinning, crown closure rates of the coniferous plantation forest reached a level similar to the pre-thinning period, and runoff rates returned to the pre-thinning level, due to forest growth. As a result of this study, a proposed direction for Korea’s forest policy for water resource management is presented for the future.

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The long-term water balance (1972–2004) of upland forestry and grassland at Plynlimon, mid-Wales

Hydrology and Earth System Sciences ◽

10.5194/hess-11-44-2007 ◽

2007 ◽

Vol 11 (1) ◽

pp. 44-60 ◽

Cited By ~ 48

Author(s):

V. Marc ◽

M. Robinson

Keyword(s):

Water Balance ◽

Water Use ◽

Forest Cover ◽

Coniferous Forest ◽

Plantation Forest ◽

Age Related ◽

Additional Water ◽

Annual Evaporation ◽

The Difference

Abstract. This paper reviews research into the hydrological impacts of UK upland forestry and updates the water balance of the Plynlimon research catchments for the period 1972–2004. Comparison of this network of densely instrumented coniferous forest and grassland catchments builds upon previously reported differences in annual evaporation of the two land uses and, most crucially, provides evidence of systematic, age-related, variations in forest evaporation losses over a managed plantation forest cycle. In comparison with the grassland catchment, the additional water use of the 70% forested catchment fell from 250 to 150 mm yr−1 because of increasing forest age; this is equivalent to a decline from 370 mm to 210 mm extra evaporation from a complete forest cover. At present, with up to half of the forest area felled or only recently replanted, the difference in evaporation between the forest and grass catchments is negligible. Knowledge of the period of maximum tree water use may be critically important for the future management of multi-use forests. This is also being investigated by micro-meteorological measurements at the scale of the forest stand using eddy covariance, in conjunction with the long-term catchment monitoring.

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Long-term effects of evapotranspiration on the flow duration curve in a coniferous plantation forest over 40 years

Hydrological Research Letters ◽

10.3178/hrl.14.1 ◽

2020 ◽

Vol 14 (1) ◽

pp. 1-8

Author(s):

Kenji Tsuruta ◽

Yoshiko Kosugi ◽

Masanori Katsuyama ◽

Ken’ichirou Kosugi ◽

Masakazu Suzuki ◽

...

Keyword(s):

Flow Duration Curve ◽

Long Term Effects ◽

Plantation Forest ◽

Flow Duration ◽

Coniferous Plantation ◽

Over 40 Years

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Effect of Forest Growth and Thinning on the Long-term Water Balance in a Coniferous Forest

Korean Journal of Agricultural and Forest Meteorology ◽

10.5532/kjafm.2010.13.4.157 ◽

2011 ◽

Vol 13 (4) ◽

pp. 157-164 ◽

Cited By ~ 4

Author(s):

Hyung-Tae Choi

Keyword(s):

Water Balance ◽

Coniferous Forest ◽

Forest Growth

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Plantation forest leases: experiences of New Zealand Māori

Canadian Journal of Forest Research ◽

10.1139/x2012-113 ◽

2012 ◽

Vol 42 (9) ◽

pp. 1678-1686 ◽

Cited By ~ 1

Author(s):

Stephanie Rotarangi

Keyword(s):

Forest Management ◽

Document Analysis ◽

Third Parties ◽

Plantation Forest ◽

Plantation Forests ◽

Management Techniques ◽

Environmental Considerations ◽

Public Views ◽

Depth Interviews

Numerous scholars agree that to integrate stakeholder demands into forest management is the central challenge facing forestry science. A necessary step is to translate public views and expectations into forest management techniques. This study uses document analysis and in-depth interviews to understand the values and expectations of New Zealand’s indigenous people (Māori) who have exotic species forests planted on their ancestral land. The two case studies involve long-term forest lease arrangements where Māori families are the collective owners of the land but the forest is managed by third parties. The results suggest that the landowners’ overall view of forestry is more critically influenced by political frameworks than by forest management techniques. The structures of governance and tenure and the legislation affecting the land are viewed as complicated and constraining. However, after decades of experience, Māori have successfully incorporated plantation forests into their sense of people and place. Despite difficulties and disappointments, the land use of forestry and forest regimes are, overall, viewed favourably by the landowners, consistent with environmental considerations and their culture and values.

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Planning a system of permanent sample plots for integrated long-term studies of community-based forest management

Banko Janakari ◽

10.3126/banko.v16i2.965 ◽

1970 ◽

Vol 16 (2) ◽

pp. 3-11 ◽

Cited By ~ 10

Author(s):

H Meilby ◽

L Puri ◽

M Christensen ◽

S Rayamajhi

Keyword(s):

Forest Management ◽

Key Words ◽

Research Note ◽

Managed Forests ◽

Community Based ◽

Permanent Sample Plots ◽

Long Term Studies

To monitor the development of four community-managed forests, networks of permanent sample plots were established in 2005 at sites in Chitwan, Kaski and Mustang Districts, Nepal. This research note documents the procedures used when preparing for establishment of the plot networks, evaluates the applied stratification of the forest on the basis of data gathered in pilot surveys conducted in the early 2005, and provides a discussion on the implications of the choices made. Key words: Community-managed forests; permanent sample plots; stratification; allocation; estimates Banko Janakari Vol.16(2) 2006 pp.3-11

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Shedding New Light on Mountainous Forest Growth: A Cross-Scale Evaluation of the Effects of Topographic Illumination Correction on 25 Years of Forest Cover Change across Nepal

Remote Sensing ◽

10.3390/rs13112131 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2131

Author(s):

Jamon Van Den Hoek ◽

Alexander C. Smith ◽

Kaspar Hurni ◽

Sumeet Saksena ◽

Jefferson Fox

Keyword(s):

Remote Sensing ◽

Geographic Distribution ◽

Classification Accuracy ◽

Forest Cover ◽

Forest Growth ◽

Forest Cover Change ◽

Scale Evaluation ◽

Beneficial Effects ◽

Affect Detection

Accurate remote sensing of mountainous forest cover change is important for myriad social and ecological reasons, but is challenged by topographic and illumination conditions that can affect detection of forests. Several topographic illumination correction (TIC) approaches have been developed to mitigate these effects, but existing research has focused mostly on whether TIC improves forest cover classification accuracy and has usually found only marginal gains. However, the beneficial effects of TIC may go well beyond accuracy since TIC promises to improve detection of low illuminated forest cover and thereby normalize measurements of the amount, geographic distribution, and rate of forest cover change regardless of illumination. To assess the effects of TIC on the extent and geographic distribution of forest cover change, in addition to classification accuracy, we mapped forest cover across mountainous Nepal using a 25-year (1992–2016) gap-filled Landsat time series in two ways—with and without TIC (i.e., nonTIC)—and classified annual forest cover using a Random Forest classifier. We found that TIC modestly increased classifier accuracy and produced more conservative estimates of net forest cover change across Nepal (−5.2% from 1992–2016) TIC. TIC also resulted in a more even distribution of forest cover gain across Nepal with 3–5% more net gain and 4–6% more regenerated forest in the least illuminated regions. These results show that TIC helped to normalize forest cover change across varying illumination conditions with particular benefits for detecting mountainous forest cover gain. We encourage the use of TIC for satellite remote sensing detection of long-term mountainous forest cover change.

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Development and Verification of the Available Number of Water Intake Days in Ungauged Local Water Source Using the SWAT Model and Flow Recession Curves

Water ◽

10.3390/w13111511 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1511

Author(s):

Jung-Ryel Choi ◽

Il-Moon Chung ◽

Se-Jin Jeung ◽

Kyung-Su Choo ◽

Cheong-Hyeon Oh ◽

...

Keyword(s):

Water Supply ◽

Water Intake ◽

Water Resource Management ◽

Assessment Tool ◽

Swat Model ◽

High Water ◽

Coefficient Of Determination ◽

Severe Drought ◽

Regional Government

Climate change significantly affects water supply availability due to changes in the magnitude and seasonality of runoff and severe drought events. In the case of Korea, despite high water supply ratio, more populations have continued to suffer from restricted regional water supplies. Though Korea enacted the Long-Term Comprehensive Water Resources Plan, a field survey revealed that the regional government organizations limitedly utilized their drought-related data. These limitations present a need for a system that provides a more intuitive drought review, enabling a more prompt response. Thus, this study presents a rating curve for the available number of water intake days per flow, and reviews and calibrates the Soil and Water Assessment Tool (SWAT) model mediators, and found that the coefficient of determination, Nash–Sutcliffe efficiency (NSE), and percent bias (PBIAS) from 2007 to 2011 were at 0.92, 0.84, and 7.2%, respectively, which were “very good” levels. The flow recession curve was proposed after calculating the daily long-term flow and extracted the flow recession trends during days without precipitation. In addition, the SWAT model’s flow data enables the quantitative evaluations of the number of available water intake days without precipitation because of the high hit rate when comparing the available number of water intake days with the limited water supply period near the study watershed. Thus, this study can improve drought response and water resource management plans.

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Evaluating Machine Learning and Geostatistical Methods for Spatial Gap-filling of Monthly ESA CCI Soil Moisture in China

Remote Sensing ◽

10.3390/rs13142848 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2848

Author(s):

Hao Sun ◽

Qian Xu

Keyword(s):

Machine Learning ◽

Soil Moisture ◽

Water Resource Management ◽

Large Scale ◽

Gap Filling ◽

Spatial Continuity ◽

Study Results ◽

Data Gaps

Obtaining large-scale, long-term, and spatial continuous soil moisture (SM) data is crucial for climate change, hydrology, and water resource management, etc. ESA CCI SM is such a large-scale and long-term SM (longer than 40 years until now). However, there exist data gaps, especially for the area of China, due to the limitations in remote sensing of SM such as complex topography, human-induced radio frequency interference (RFI), and vegetation disturbances, etc. The data gaps make the CCI SM data cannot achieve spatial continuity, which entails the study of gap-filling methods. In order to develop suitable methods to fill the gaps of CCI SM in the whole area of China, we compared typical Machine Learning (ML) methods, including Random Forest method (RF), Feedforward Neural Network method (FNN), and Generalized Linear Model (GLM) with a geostatistical method, i.e., Ordinary Kriging (OK) in this study. More than 30 years of passive–active combined CCI SM from 1982 to 2018 and other biophysical variables such as Normalized Difference Vegetation Index (NDVI), precipitation, air temperature, Digital Elevation Model (DEM), soil type, and in situ SM from International Soil Moisture Network (ISMN) were utilized in this study. Results indicated that: 1) the data gap of CCI SM is frequent in China, which is found not only in cold seasons and areas but also in warm seasons and areas. The ratio of gap pixel numbers to the whole pixel numbers can be greater than 80%, and its average is around 40%. 2) ML methods can fill the gaps of CCI SM all up. Among the ML methods, RF had the best performance in fitting the relationship between CCI SM and biophysical variables. 3) Over simulated gap areas, RF had a comparable performance with OK, and they outperformed the FNN and GLM methods greatly. 4) Over in situ SM networks, RF achieved better performance than the OK method. 5) We also explored various strategies for gap-filling CCI SM. Results demonstrated that the strategy of constructing a monthly model with one RF for simulating monthly average SM and another RF for simulating monthly SM disturbance achieved the best performance. Such strategy combining with the ML method such as the RF is suggested in this study for filling the gaps of CCI SM in China.

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Long-term changes of river discharge regime in Latvia

Hydrology Research ◽

10.2166/nh.2008.033 ◽

2008 ◽

Vol 39 (2) ◽

pp. 133-141 ◽

Cited By ~ 5

Author(s):

Maris Klavins ◽

Valery Rodinov

Keyword(s):

Climate Variability ◽

River Discharge ◽

Water Resource Management ◽

Regional Climate ◽

Hydrological Regime ◽

High Water ◽

Regime Changes ◽

Long Term Changes ◽

Discharge Regime

The study of changes in river discharge is important for regional climate variability characterization and for development of an efficient water resource management system. The hydrological regime of rivers and their long-term changes in Latvia were investigated. Four major types of river hydrological regimes, which depend on climatic and physicogeographic factors, were characterized. These factors are linked to the changes observed in river discharge. Periodic oscillations of discharge, and low- and high-water flow years are common for the major rivers in Latvia. A main frequency of river discharge regime changes of about 20 and 13 years was estimated for the studied rivers. A significant impact of climate variability on the river discharge regime has been found.

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