Assessing the effect of soil parameterization in land use change impact modeling

This study addresses the importance of integrating the effect of land use on soil infiltration rate into land use change impact modeling. Based on a validated version 9.05.04 of the Water balance Simulation Model-WaSiM (statistical quality measures > 0.7), and field measurement of the infiltration rate under cropland and fallow, sixteen model simulations were performed. The impact of land use change is computed comparing LULC status of years 1990 and 2013. The effect of soil parameterization is computed using a refined soil map integrating land use change impact of soil infiltration rate and a classic soil map not considering this interaction. The results show differences in model results as an effect of soil parameterization approaches, indicating that the model is sensitive to the integration of LULC related effects on soil hydraulic conductivity. These differences are more pronounced with increasing modeling time steps (24 and 28 h). The signal-to-noise-ratio indicates that, results achieved in LULC impact assessment with a classic and a refined soil parameterization are very comparable except for interflow.

Soil Infiltration Management on Perspective of Sustainable Development Goals (SDGs)

UB Forest is a Forest Area with Special Purpose (KHDTK) located on the slopes of Mount Arjuno. Before being managed by the University of Brawijaya, there was a change in land cover from natural forest to pine and mahogany production forest. This change was a result of the PHBM (Collaborative Forest Management) contract agreement between Perhutani and the community to carry out agricultural management. The input of organic matter with different quality and quantity will affect the organic matter content and in turn will affect the physical properties of the soil such as bulk density, density and soil porosity. Soil porosity is a physical property of soil that affects soil infiltration. The objective of this study is to identify and analyze the management of Forest Areas and to build a green economy model in the management of KHDTK University of Brawijaya Forest in the Perspective of Sustainable Development Goals (SDGs) in Malang Regency. The method used in this research is qualitative research. Implementation of green economy model in the management of KHDTK University of Brawijaya Forest in the concept of forestry sector contribution related to climate change; the concept of sustainable forest resource management; and the concept of environmental service providers. The results of the infiltration measurement using the single ring infiltrometer method can better describe the infiltration that occurs in the soil. The highest soil infiltration is in protected areas with a soil infiltration rate of 131.33 cm/hour (single ring infiltrometer). Meanwhile, the lowest infiltration was found in the pine production forest plot overlaid with seasonal crops with a soil infiltration rate of 12 cm/hour (single ring infiltrometer).

Non-potable Water Quality Assessment Methodology for Water Conservation in Arid Climates

This paper documents a non-potable water (NPW) quality assessment methodology for a decentralized non-potable water system in Abu Dhabi (AD), capital city of the United Arab Emirates (UAE), which is dominated by sandy and salty soil, high temperature, and humidity. The context is a medical facility case study (MFCS) in AD, which includes a landscape 50% as large as its building footprint. The project identified the need to investigate the impact of air handling unit (AHU) air conditioning (A/C) condensate water (CW) quality on soil health and building hydraulic systems. The aim of the research was to measure the impact of using recycled on-site NPW sources in a MFCS in AD, to alleviate the use of desalinated potable water and reduce associated energy consumption, operation cost, and greenhouse gas emissions for landscape irrigation (LI) and water feature (WF) use. CW has been tested in 2016 and in 2017 and analysed against local authority’s parameter limits to establish suitability for LI and WF use. The findings are that in AD CW classification and characterization is a gap in knowledge whereby salinity and toxicity concentration limits should be addressed by the local authority because CW has an impact on soil infiltration rate due its low dissolved salt content as evidenced by the water test results. The recommendations for this paper are to develop a sustainable water conservation and reuse (SWC) strategy forming the basis for a water protocol by the competent authority for regional medical facility including a methodology for assessing on-site NPW quality for outdoor reuse to reduce soil infiltration problems and consequently conserve water and associated energy. The next steps are to confirm if the MFCS soil infiltration rate is affected by the CW or other factors, and to test additional NPW types.

Developing a fuzzy logic model for predicting soil infiltration rate based on soil texture properties

The prediction of the soil infiltration rate is advantageous in hydrological design, watershed management, irrigation, and other agricultural studies. Various techniques have been widely used for this with the aim of developing more accurate models; however, the improvement of the prediction accuracy is still an acute problem faced by decision makers in many areas. In this paper, an intelligent model based on a fuzzy logic system (FLS) was developed to obtain a more accurate predictive model for the soil infiltration rate than that generated by conventional methods. The input variables that were considered in the fuzzy model included the silt and clay contents. The developed fuzzy model was tested against both the observed data and multiple linear regression (MLR). The comparison of the developed fuzzy model and MLR model indicated that the fuzzy model can simulate the infiltration process quite well. The coefficient of determination, root mean square error, mean absolute error, model efficiency, and overall index of the fuzzy model were 0.953, 1.53, 1.28, 0.953, and 0.954, respectively. The corresponding MLR model values were 0.913, 2.37, 1.92, 0.913, and 0.914, respectively. The sensitivity results indicated that the clay content is the most influential factor when the FLS-based modelling approach is used for predicting the soil infiltration rate.

Evaluation of the Water Conservation Function of Different Forest Types in Northeastern China

Water conservation is an important function of forest ecosystems, but it is still unclear which forest types function best in this regard. We investigated the water conservation function indicators including the water-holding rate of branches and leaves (BLwr), water-holding capacity of litter (Lwc), water absorption rate of litter (Lwr), soil infiltration rate (Ir), soil and water content (SWC), soil water storage (SWS), and soil organic matter (SOM) accumulation of five forest types (Larix gmelinii forests, Pinus koraiensis forests, Robinia pseudoacacia forests, Pinus tabulaeformis forests, and mixed forests) and evaluated them using the gray correlation method (GCM). The results indicate that the BLwr of five stands in the study area varied from 18.3% to 33.5%. The SWC and SWS of the R. pseudoacacia stand were 13.76% and 178.9 mm, respectively, which was significantly higher than that of the other stands (p < 0.05). The SOM was similar for the R. pseudoacacia (0.23%), mixed forest (0.22%), and L. gmelinii (0.22%) sites. The BLwr, Lwc, Lwr, SWC, and SWS values of broad-leaved tree species were higher than those of the mixed species, followed by those for coniferous tree species. Soil infiltration rate followed the order L. gmelinii > P. koraiensis > mixed forest > P. tabulaeformis > R. pseudoacacia. Based on our results, the R. pseudoacacia stand had the highest water conservation ability, while the lowest performance was found for the P. tabuliformis site. This suggests that, in order to enhance the water conservation function of forests in northeastern China, the focus should be on the establishment of R. pseudoacacia forests.