Impact Of Land Use Land Cover Research Articles

Impact of LUCC on landscape pattern in the Yangtze River Basin during 2001–2019

Evaluating the influences of LUCC (Land Use/Land Cover Change) on landscape pattern is significant for understanding and improving ecological environment system management. This study used landscape pattern as an important indicator to estimate the impacts of the LUCC in the Yangtze River Basin from 2001 to 2019. Based on the remote sensing images of LULC (Land Use/Land Cover) in the Yangtze River Basin in 2001–2019, the dynamic attitude and transfer matrix of LULC, and landscape pattern indices were employed to analyze the LUCC and the impact of LULC on the landscape pattern of the Yangtze River Basin. The results of LUCC show that the main LUCC in the Yangtze River Basin during 2001–2019 is mainly manifested by the increase of water body, forest, wetland, crop/natural vegetation mosaic (NVM) and urban, among which the forest increased the most by 62,635 km2. The areas of grassland and cropland are decreasing, with the grassland decreasing the most. Forest, crop/NVM and cropland are transformed into grassland, which complements the lack of grassland to some extent. LUCC in the Yangtze River Basin is most intense between grassland and forest. Landscape pattern shows: Grassland occupies an important advantage in the whole landscape structure. Forest, grassland and urban landscapes are seriously fragmented, and their LSI (Landscape Shape Index) is more complex than others. The connectivity between various landscape types is weakened, and the degree of landscape fragmentation is increased, but the LULC structure is becoming more and more abundant. The areas with high landscape fragmentation value have richer landscape diversity and diverse LULC types. There is a strong correlation between grassland and the four landscape pattern indices. The change of landscape pattern in the Yangtze River Basin is influenced by natural factors and LUCC in the Yangtze River Basin, and the change caused by human activities is the main driving factor of LUCC.

Impact of Land Use-Land Cover and Climatic Pattern on Sediment Yield of Two Contrasting Sub-Catchments in Upper Tapi Basin, India

Abstract Long-term and short-term assessments of sediment yield from river basins are required in planning soil conservation measures, water storage in reservoirs and prediction of morphological responses in rivers. In present study, detailed quantification of land-use land-cover and climate variabilityin two contrasting subcatchments of Upper Tapi basin, India, are reported for period 1980-2010. The pattern of measured sediment concentration, decadal and intra-annual variations of sediment yield at the outlets of boththe sub-catchments are presented and attributed with land-use land-cover and climate variability of the relevant periods. Higher sediment and water yields observed at the outlet of Burhanpur sub-catchment are due to steep and hilly topography, excessive deforestation and relatively high simple daily monsoonal intensity index (SDMII) within the sub-catchment versus Purna sub-catchment. In both the sub-catchments, maximum and minimum sediment concentrations are in July and September months respectively. Higher sediment concentration at the outlet of Purna sub-catchment is due to excessive alluvial deposits, extensive agricultural activities and generation of correspondingly less runoff within the sub-catchment. The observed reduction in sediment yield pattern in recent years is due to development of minor hydraulic structures (water area), decrease in scrub lands, increased planned agricultural land and decrease in the SDMII within both sub-catchments. The correlation analyses have indicated that total monsoonal basin average rainfall (TMBAR), rainy days (RD) and SDMII have been found to be significantly correlated with sediment yield for Burhanpur sub-catchment visà-vis SDMII and TMBAR for the Purna sub-catchment. Also, the sediment yield from the sub-catchments in the past have been found to be excessively higher than planned reservoir sedimentation of Hatnur reservoir, located at the outlet of the Upper Tapi basin.

Assessing and Predicting Changes of the Ecosystem Service Values Based on Land Use/Land Cover Changes With a Random Forest-Cellular Automata Model in Qingdao Metropolitan Region, China

With the rapid development of economy, the land use/land cover (LULC) in Qingdao Metropolitan Region had undergone tremendous changes, thus causing negative effects on ecosystem functions and services. Based on the analyses of remote sensing images and statistical yearbook data, the ecosystem service value (ESV) was quantitative monetary accounted by using the equivalent factor method, and the impact of LULC on ecosystem services was analyzed. A random forest-cellular automata (RF-CA) model and the multiscenario simulation were employed to forecast the LULC changes for 2032. Our results showed that the total ESV of Qingdao Metropolitan Region decreased from 26.17 billion RMB in 1990 to 20.86 billion RMB in 2017. Based on the validation of RF-CA model, the total ESV in 2032 might continuously decline compared with that in 2017, while the ESV under ecological protection priority scenario was higher than business-as-usual scenario. The reduction of ESV was mainly caused by the LULC changes, such as the loss of land with high ecological value. This research provided the useful information for the intensive utilization of land resources and the sustainable development of ecological environment in Qingdao Metropolitan Region.

Dynamics of Selected Soil Quality Indicators in Response to Land Use/Cover and Elevation Variations in Wanka Watershed, Northwestern Ethiopian Highlands

Abstract Soil quality (SQ) dynamics assessment vis-à-vis land use/land cover (LULC) and elevation variations in Ethiopia is desirable as elevation impact on land use is highly pronounced. This study examined SQ indicators dynamics across LULC and elevation variations. For this, surface soil samples (0−20 cm) were collected from the recognized LULC categories of different elevations in Wanka watershed, northwestern Ethiopian highlands. Both disturbed and undisturbed soil samples that were taken from three adjacent LULC (natural forest, grazing and cultivated lands) and elevation (2238–2300, 2400–2600, and 2700–2800) classes analysed for the selected physico-chemical SQ indicators. Two-way ANOVA, Tukey’s multiple comparison test and SQ deterioration index were computed. The impact of LULC and elevation was found significant on key SQ indicators. In cultivated and grazing lands, soil organic matter (SOM) and soil nutrients like total nitrogen declined significantly (p < 0.01). Conversely, bulk density increased significantly (p < 0.01). The divalent basic cations (Ca2+ and Mg2+), cation exchange capacity and pH significantly (p < 0.01) decreased in upper elevation. Synergetic effect of LULC and elevation variations was found significant (p < 0.01) on SOM, total nitrogen, available phosphorus, water content at field capacity and soil particle distribution (silt and clay). Thus, elevation specific land management strategies that improve these SQ indicators need to be emphasized.

Modeling and assessing land-use and hydrological regimes to future land-use scenario for sustainable watershed management in a semi-arid region of southern India

The present study investigates impact of land use land cover (LULC) change and water harvesting interventions in Kanva watershed, a rural catchment in Kaveri basin, located in semi arid region of southern India. Remote sensing data and Soil and Water assessment Tool hydrological model was used to assess changes in total water yield, groundwater recharge, percolation and evapotranspiration. Post classification change detection technique was used for LULC change analysis in 1992, 2001, 2008 and 2014. Modelling was also performed to assess potential impact of LULC using predicted land use scenario of 2022. A comparison between 1995–2003 (pre-watershed management) and 2004–2016 (post-watershed management) simulations indicated an increase of 1.01%, 4.65% and 1.74% in average runoff coefficient, groundwater recharge coefficient and percolation coefficient respectively, and decrease in evaporation coefficient by 0.51%. The results showed that LULC changes and water harvesting accounted for a difference in hydrological components between these two periods. Scenario analyses were performed for different adoption rates of rain water harvesting (RWH) interventions in sub-watersheds of Kanva watershed and its impact on hydrological parameters, especially on total water yield was identified. The analysis indicated that average runoff coefficient was 9.16% during pre-watershed period and 9.25% during post-watershed period. Further up-scaling of RWH would reduce the flow and runoff coefficient may decrease to 6.07% if RWH is adopted in whole of Kanva watershed. The results suggested that if extensive RWH is carried out in the Kanva watershed, it would result in unsustainable water management due to reduced flow downstream. The study found that the sustainability of watersheds in arid and semi-arid regions is very important given the uncertainties in future hydrologic regimes due to changes in land cover and changes in extreme rainfall patterns thus requiring suitable management interventions.

Model-based study of the role of rainfall and land use–land cover in the changes in the occurrence and intensity of Niger red floods in Niamey between 1953 and 2012

Abstract. Since 1950, the Niger River basin has gone through three main climatic periods: a wet period (1950–1960), an extended drought (1970–1980) and since 1990 a recent partial recovery of annual rainfall. Hydrological changes co-occur with these rainfall fluctuations. In most of the basin, the rainfall deficit caused an enhanced discharge deficit, but in the Sahelian region the runoff increased despite the rainfall deficit. Since 2000 the Sahelian part of the Niger has been hit by an increase of flood hazards during the so-called red flood period. In Niamey city, the highest river levels and the longest flooded period ever recorded occurred in 2003, 2010, 2012 and 2013, with heavy casualties and property damage. The reasons for these changes, and the relative role of climate versus land use–land cover (LULC) changes are still debated and are investigated in this paper. The evolution of the Niger red flood in Niamey from 1950 to 2012 is analysed based on long-term records of rainfall (three data sets based on in situ and/or satellite data) and discharge, and a hydrological model. The model is first run with the present LULC conditions in order to analyse solely the effect of rainfall variability. The impact of LULC and drainage area modification is investigated in a second step. The simulations based on the current surface conditions are able to reproduce the observed trend in the red flood occurrence and intensity since the 1980s. This has been verified with three independent rainfall data sets and implies that rainfall variability is the main driver for the red flood intensification observed over the last 30 years. The simulation results since 1953 have revealed that LULC and drainage area changes need to be invoked to explain the changes over a 60-year period.

Impacts of land use–land cover change and urbanization on flooding: A case study of Oshiwara River Basin in Mumbai, India

In the present study, the impact of land use–land cover (LULC) change and urbanization on floods are investigated for an expanding urban catchment of the Oshiwara River in Mumbai, India. For the study area, the land use change was estimated between 1966, 2001 and 2009 by using the topographic map and satellite images. The analysis of LULC change revealed that the change between 1966 and 2001 was slower than that between 2001 and 2009. The LULC analysis revealed a 74.84% increase in the built up area with a 42.8% decrease in open spaces between the years 1966 and 2009, with substantial increase in urbanization. The impact of LULC on flood hydrograph for different return periods was ascertained by using the HEC-GeoHMS and HEC-HMS models. In the past 43years, the increase in peak runoff and runoff volume is marginally varied by 3.0% and 4.45% for the 100-year return period and 10.4% and 12.2% for the 2-year return period respectively, although the built-up area increased by 74.84%. The flood inundation area is increased by 5.61% for the 100-year return period and 6.04% for the 10-year return period between the same time period. The results showed that lower return periods led to a maximum change in peak discharge/volume of runoff compared to higher return periods for change in land use conditions. Further, a flood hazard analysis has been carried out and it showed that the area in highly hazardous zone is increased by 64.29% as compared to less hazardous zone where it is decreased by 32.14%. Overall, the total flood hazard area is increased by 22.27%. The developed flood plain and flood hazard maps can be used by the local Municipal body to prepare flood mitigation and early evacuation management plans during floods and as a criteria for insurance of any property by insurance organizations.

Detecting the effects of land use/land cover on mean annual streamflow in the Upper Mississippi River Basin, USA

Summary The effects of land use/land cover (LULC) along with other climate and geomorphologic factors on mean annual streamflow in the Upper Mississippi River Basin (UMRB) were explored using a nonlinear model applied to a spatial dataset of more than 180,000 catchments. The model was linearized and solved via a geospatial regression model to deal with spatial dependency in data. Results show that LULC is a very important agent with respect to its impact on mean annual streamflow in UMRB. Compared with other climate and geomorphologic factors, the signature of LULC on streamflow which was shown through various measures in this study is evident and significant. The magnitude of the impact on streamflow varies from one LULC to another. It is not a simple function of a LULC’s spatial extent but arguably a result of complex interactions among various LULCs as well as other climate and geomorphologic factors. Our analysis indicates that caution needs to be taken in comparing different studies or in generalization across scales regarding the impact of LULC on streamflow. It is because the result of a study is not only the outcome of the geophysical processes observed at a particular spatial and temporal scales but also a product of the approach, model, variables, and/or measures used in the study. Methodologically the proposed model provided an effective way to utilize an extensive spatial dataset of various climatic, geomorphologic, and LULC variables for a large region like UMRB to assess and compare the impact of various factors on mean annual streamflow at regional scale. Furthermore, the model was able to handle spatial dependency in data while avoiding the common problem of nested input in hydrologic modeling.

Assessment of urban heat island effect for different land use–land cover from micrometeorological measurements and remote sensing data for megacity Delhi

Urban heat island intensities (UHI) have been assessed based on in situ measurements and satellite-derived observations for the megacity Delhi during a selected period in March 2010. A network of micrometeorological observational stations was set up across the city. Site selection for stations was based on dominant land use–land cover (LULC) classification. Observed UHI intensities could be classified into high, medium and low categories which overall correlated well with the LULC categories viz. dense built-up, medium dense built-up and green/open areas, respectively. Dense urban areas and highly commercial areas were observed to have highest UHI with maximum hourly magnitude peaking up to 10.7 °C and average daily maximum UHI reaching 8.3 °C. UHI obtained in the study was also compared with satellite-derived land surface temperatures (LST). UHI based on in situ ambient temperatures and satellite-derived land surface temperatures show reasonable comparison during nighttime in terms of UHI magnitude and hotspots. However, the relation was found to be poor during daytime. Further, MODIS-derived LSTs showed overestimation during daytime and underestimation during nighttime when compared with in situ skin temperature measurements. Impact of LULC was also reflected in the difference between ambient temperature and skin temperature at the observation stations as built-up canopies reported largest gradient between air and skin temperature. Also, a comparison of intra-city spatial temperature variations based UHI vis-a-vis a reference rural site temperature-based UHI indicated that UHI can be computed with respect to the station measuring lowest temperature within the urban area in the absence of a reference station in the rural area close to the study area. Comparison with maximum and average UHI of other cities of the world revealed that UHI in Delhi is comparable to other major cities of the world such as London, Tokyo and Beijing and calls for mitigation action plans.