No abstract

Landcover changes (LCC) are one indicator of an increase in population in a watershed area that demands the provision of housing locations, road infrastructure, and productive land to meet the needs of life. LCC can positively impact the form of increased land use values and incomes, while also negative impacts in the form of erosion, landslides, and floods. The watershed area should have a balance in its development. This research is important as a first step in overcoming changes in land cover that can threaten the sustainability and sustainability of the Kuranji watershed. The aim of the study is to reveal the LCC from 1985 to 2018 and its causal factors in the Kuranji watershed. The methodology used is descriptive qualitative with 60 respondents. Data were obtained by interviewing respondents. Respondents are those having agricultural land and working in the agricultural sector and this research was carried out in 2019. The results showed an increase in the type of land cover of settlements and mixed gardens, while forests, rice fields and shrubs have decreased. The main factor influencing changes in land cover is economical (59%), followed by social factors (25%) and political factors (16%). It was also found that local wisdom of the Minangkabau culture was able to reduce LCC. In Minangkabau, the land owned by the community, in general, is a legacy from generation to generation that cannot be sold without significant reasons.

Changes in land use in the Air Dingin watershed (DAS) area in Padang City, Indonesia, lead to a decrease in rainwater infiltration volume to the ground. Some land use in the Latung sub-watershed decrease in infiltration capacity with an increase in surface runoff. This research aims to determine the effect of land-use changes on infiltration capacity and surface runoff. Purposive sampling method was used in this research. The infiltration capacity was measured directly in the field using a double-ring infiltrometer, and the data was processed using the Horton model. The obtained capacity was quantitatively classified using infiltration zoning. Meanwhile, the Hydrologic Engineering Center - Hydrology Modeling System with the Synthetic Unit Hydrograph- Soil Conservation Service -Curve Number method was used to analyze the runoff discharge. The results showed that from the 13 measurement points carried out, the infiltration capacity ranges from 0.082 - 0.70 cm/minute or an average of 0.398 cm/minute, while the rainwater volume is approximately 150,000 m3/hour/km2. Therefore, the soil infiltration capacity in the Latung sub-watershed is in zone VI-B or very low. This condition had an impact on changes in runoff discharge in this area, from 87.84 m3/second in 2010 to 112.8 m3/second in 2020 or a nail of 22.13%. Based on the results, it is concluded that changes in the land led to low soil infiltration capacity, thereby leading to an increase in surface runoff.