Land change effects on ecosystem degradation across Nigerian agro-ecological zones from 1975 through 2020

2021 ◽  
Author(s):  
Felicia Akinyemi ◽  
Chinwe Ifejika Speranza
Keyword(s):  
Land Use ◽  
Land Degradation ◽  
Vegetation Index ◽  
Land Change ◽  
Land Area ◽  
Degraded Land ◽  
Vegetation Productivity ◽  
Ecological Zones ◽  
Settlement Areas ◽  
Agro Ecological Zones

<p>Land system change is implicated in many sustainability challenges as its alteration impacts ecosystems and exacerbate the vulnerability of communities, particularly where livelihoods are largely dependent on natural resources. The production of a land use-cover map for year 2020 extended the time-series for assessing land use-cover dynamics over a period of 45 years (1975-2020). The case of Nigeria is examined as the land area encompass several agro-ecological zones. The classification scheme countries utilise for estimating Land Degradation Neutrality baseline and monitoring of the Sustainable Development Goal 15.3.1 indicator (proportion of degraded land over total land area) was used, based on seven land use-cover classes (tree-covered area, grassland, cropland, wetland, artificial surface area, otherland, and waterbody). Severity of land degradation, computed as changes in vegetation productivity using the Enhanced Vegetation Index (EVI), as well as changes in ecosystem service values were examined across the different land use-cover types, in areas of change and persistence. Land degradation is most severe in settlement areas and wetlands with declining trends in 34% of settlement areas and 29% in wetlands respectively. About 19% of tree-covered areas experienced increasing trends. In some areas of land use-cover persistence, vegetation productivity declined despite no land change occurring. For example, vegetation productivity declined in about 35% and 9% of persistent wetlands and otherland respectively between 2000 and 2020, whereas there was improvement in 22% of persistent grasslands, 18% of persistent otherlands and 12% of persistent croplands. In land change areas, about 12% and 8% of wetlands and tree-covered areas had declining vegetation trends respectively, whereas it improved the most in croplands (20%), and grasslands (16%). With some wetland, cropland and otherland areas degrading the most, protecting these critical ecosystems is required to sustain their functions and services. The finding that vegetation productivity may decline in areas of persistence underscores the importance of intersecting land use-cover (in terms of persistence and change) with vegetation productivity to identify pathways for enhancing ecological sustainability.</p>

scholarly journals SPATIAL-TEMPORAL CHANGES OF LAND DEGRADATION CAUSED BY NATURAL AND HUMAN INDUCED FACTORS: CASE STUDY OF BULGAN PROVINCE IN CENTRAL MONGOLIA

2021 ◽  
Vol XLIII-B4-2021 ◽  
pp. 79-85
Author(s):  
S. Dalantai ◽  
E. Sumiya ◽  
Y. Bao ◽  
M. Otgonbayar ◽  
U. Mandakh ◽  
...  
Keyword(s):  
Land Use ◽  
Land Degradation ◽  
Geographical Information ◽  
Land Use Type ◽  
Degraded Land ◽  
Gis And Remote Sensing ◽  
Central Mongolia ◽  
Temperature And Precipitation ◽  
Multi Temporal ◽  
Land Degradation And Desertification

Abstract. Land degradation and desertification have been ranked as a major environmental issue for arid and semi-arid regions is a comprehensive concept that depends on many factors. Detecting early land degradation is a significant issue of social and environmental with geographical information system (GIS) and remote sensing methods has been used for the interpretation of spatial-temporal data. In this study, the assessment of the current state of land degradation is influenced by several complexes of the natural and anthropological causes. The results of land degradation assessment carried out for Bulgan province of Mongolia using multi-temporal resourced data as climate condition (vegetation growing season of temperature and precipitation), land use type (density of seasonal camps of herder households, roads, cropland, settlements) and MODIS vegetation product data were used to estimate land degradation change period from 2000 to 2018 and accessed it’s for effecting on degradation over last 19 years. We obtained a prediction of land degradation integrated with indicators and based on the spatial pattern of human influence. One of the main indicators for land degradation was land use type as pasture usage of livestock husbandry in Bulgan province, overgrazing is the most widespread cause of land degradation, particularly around permanent location of herders and livestock affecting about moderately and slightly degraded land is 72.78% of study total area.

scholarly journals Multicriteria decision-support system to assess the potential of exclosure-based conservation in Ethiopia

2020 ◽  
pp. 1-15 ◽  
Author(s):  
Kefyalew Sahle Kibret ◽  
Amare Haileslassie ◽  
Wolde Mekuria Bori ◽  
Petra Schmitter
Keyword(s):  
Land Use ◽  
Decision Support ◽  
Ecosystem Services ◽  
Land Degradation ◽  
Decision Support Tool ◽  
River Basins ◽  
Land Area ◽  
Support Tool ◽  
Ex Ante ◽  
Multicriteria Decision Support

Abstract Land degradation is a global challenge that affects lives and livelihoods in many communities. Since 1950, about 65% of Africa's cropland, on which millions of people depend, has been affected by land degradation caused by mining, poor farming practices and illegal logging. One-quarter of the land area of Ethiopia is severely degraded. As part of interventions to restore ecosystem services, exclosures have been implemented in Ethiopia since the 1980s. But the lack of tools to support prioritization and more efficient targeting of areas for large-scale exclosure-based interventions remains a challenge. Within that perspective, the overarching objectives of the current study were: (i) to develop a Geographic Information System-based multicriteria decision-support tool that would help in the identification of suitable areas for exclosure initiatives; (ii) to provide spatially explicit information, aggregated by river basin and agroecology, on potential areas for exclosure interventions and (iii) to conduct ex-ante analysis of the potential of exclosure areas for improving ecosystem services in terms of increase in above-ground biomass (AGB) production and carbon storage. The results of this study demonstrated that as much as 10% of Ethiopia's land area is suitable for establishing exclosures. This amounts to 11 million hectares (ha) of land depending on the criteria used to define suitability for exclosure. Of this total, a significant proportion (0.5–0.6 million ha) is currently under agricultural land-use systems. In terms of propriety river basins, we found that the largest amount of suitable area for exclosures falls in the Abay (2.6 million ha) and Tekeze (2.2 million ha) river basins, which are hosts to water infrastructure such as hydropower dams and are threatened by siltation. Ex-ante analysis of ecosystem services indicated that about 418 million tons of carbon can be stored in the AGB through exclosure land use. Ethiopia has voluntarily committed to the Bonn Challenge to restore 15 million ha of degraded land by 2025. The decision-support tool developed by the current study and the information so generated go toward supporting the planning, implementation and monitoring of these kinds of local and regional initiatives.

scholarly journals Spatial distribution of soil morphology and physicochemical properties to assess land degradation under different NDVI and TRI in North Halmahera, Indonesia

2021 ◽  
Vol 9 (1) ◽  
pp. 3137-3154
Author(s):  
R Rofita ◽  
Sri Nuryani Hidayah Utami ◽  
Azwar Maas ◽  
Makruf Nurudin
Keyword(s):  
Land Use ◽  
Land Degradation ◽  
Morphological Characteristics ◽  
Biomass Productivity ◽  
Soil Surface ◽  
International Standards ◽  
Soil Types ◽  
Soil Morphology ◽  
Degraded Land ◽  
Rock Fragments

Land degradation is currently a major environmental problem that can lead to decreasing biomass productivity. The causes of land degradation have been widely reported. However, the soil morphological characteristics and its detailed properties related to land degradation need to be investigated further. The research was conducted in North Halmahera Regency in March-April 2020. The study started with an overlay of basic maps such as rainfall, land use, topography, and soil types to map the degraded land units. Several land units classified from slightly damaged to severely damaged will be validated based on field observations and supported by laboratory measurements. Characterization of soil morphology and soil sampling was carried out according to USDA international standards. Sentinel 2A image and SRTM image from March to April 2020 were used to determine NDVI and TRI. The characteristics of the soils that have not been degraded tend to be found in volcanic landscapes, while those of the degraded soils tend to be found in structural and karst hills. The thickness of the degraded soil horizons tends to be shallower with an incomplete horizon arrangement, and many rock fragments are found in the soil surface layer. SOC gradually decreases in degraded soils, while the essential nutrients (N, P, and K) are relatively more varied across soil types. The improper land use without conservation on steep slopes causes the soils to be easily degraded. The soil degradation index has a linear relationship with NDVI and TRI. Thus, the revitalization of degraded lands needs to pay attention to the layout and types of vegetation with different slope levels according to the geomorphological zone.

scholarly journals Evaluation and attribution analysis of land degradation and development in Hainan Island, China

2021 ◽  
Author(s):  
Wenyin Wu ◽  
Jianan Yu ◽  
Bohao He ◽  
Yamin Jiang ◽  
Tianyan Su ◽  
...  
Keyword(s):  
Land Use ◽  
Influencing Factors ◽  
Land Degradation ◽  
Structural Equation ◽  
Vegetation Index ◽  
Net Primary Productivity ◽  
Hainan Island ◽  
Mean Annual Temperature ◽  
Land Restoration ◽  
Normalised Difference Vegetation Index

Studies on land degradation and development (LDD) and the underlying factors can help land restoration. In this study, the LDD of Hainan Island from 2000 to 2018 were measured by change vector analysis using the normalised difference vegetation index and net primary productivity (NPP). The underlying factors of LDD were selected from seven potential factors (nature factors: mean annual temperature, mean annual drought intensity, human disturbances: gross domestic product (GDP), population, population urbanisation, accumulated afforestation area, construction area) based on structural equation modelling. The results showed that 1) the degree of land-use changes into water area and construction land were higher than for the other land-use types; 2) Compared to 2000, the most serious degradation occurred in 2015, which accounting for 68.98% of the total land degradation as well as more than three-quarters of the land degradation in all surveyed years was driven by NPP; 3) The proportion of land degradation (PLD) was negatively correlated with the mean value of the land degradation and development (MLDD) in the period of five years, 2000-2018 (P<0.01); 4) The key influencing factors of PLD were temperature, accumulated afforestation area, population urbanisation, in 2000–2005, 2005–2010 and 2010–2018, respectively; 5) The key influencing factors of MLDD were temperature, GDP, population urbanisation, in 2000–2005, in 2005–2010 and in 2010–2018, respectively. Therefore, to minimise land degradation it is necessary to limit the speed of population urbanisation occurs and to improve the island environment’s adaptability to extreme climates.

scholarly journals LAND SALINIZATION DYNAMICS BASED ON FEATURE SPACE COMBINATIONS FROM LANDSAT IMAGE IN TONGYU COUNTY, NORTHEAST CHINA

2020 ◽  
Vol V-3-2020 ◽  
pp. 25-32
Author(s):  
F. Huang ◽  
P. Wang ◽  
Y. Liu ◽  
H. Y. Li
Keyword(s):  
Land Degradation ◽  
Northeast China ◽  
Surface Albedo ◽  
Vegetation Index ◽  
Feature Space ◽  
Bare Soil ◽  
Remote Sensing Images ◽  
Degraded Land ◽  
Physical Conditions ◽  
Modified Soil

Abstract. Land salinization is one of the most common land degradation processes. Tongyu county exemplifies all the forms of land degradation in Northeast China and is prone to land salinization due to its fragile physical conditions. In this study, Landsat remote sensing images are adopted to invert surface albedo, MSAVI (modified soil adjusted vegetation index), and salinity index (SI) data. The feature space models of albedo-SI and MSAVI-SI, considering the bare soil and vegetation information respectively, are constructed and compared. Land salinization changes for the period of 1998–2017 are investigated using the salinization monitoring index (SMI) and salinization detection index (SDI) extracted from the feature space models. Our results show that the land salinization situation in Tongyu county have tended to improve, associated with the biological, ecological and engineering means for the degraded land rehabilitation. The feature space models is applicable for the extraction of salinization information, and albedo-SI may evaluate land salinization levels with higher accuracy.

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