Effects of excluding grazing on the vegetation and soils of degraded sparse-elm grassland in the Horqin Sandy Land, China

Livestock grazing is a crucial cause of vegetation degradation and desertification in sandy lands. The sparse-elm grassland of Horqin Sandy Land, China has suffered severe degradation of biodiversity and ecosystem services. Management to exclude grazing is often necessary for ecological restoration, especially in arid and semi-arid regions. We report effects on vegetation and soils in a 10-year experiment to exclude livestock, completely or seasonally, in comparison with a continuously grazed area in Horqin. Complete exclusion of grazing and restriction of grazing to summer both led to significantly increased plant cover and density relative to the grazed control. Species richness increased, reflected in higher Shannon-Wiener indices; only complete exclusion increased the Simpson diversity index, whereas Pielou evenness was significantly lowest under seasonal grazing. Exclosure treatments were also associated with improved soil texture, and increased water retention, available nitrogen, total nitrogen, total carbon and total phosphorus. Soil pH and C/N ratio were highest under the seasonal grazing regime. The results indicated that exclosure management indeed improved biodiversity and ecosystem services in an erosion-prone region. Although total exclosure was most effective in restoration of degraded sparse-elm grassland, seasonal grazing management was highly beneficial and represented a good compromise with resource utilization and economic development

Spatio-Temporal Patterns of Water Table and Vegetation Status of a Deserted Area

Understanding groundwater-vegetation interactions is crucial for sustaining fragile environments of desert areas such as the Horqin Sandy Land (HSL) in northern China. This study examined spatio-temporal variations in the water table and the associated vegetation status of a 9.71 km2 area that contains meadowland, sandy dunes, and intermediate transitional zones. The depth of the water table and hydrometeorologic parameters were monitored and Landsat Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) data were utilized to assess the vegetation cover. Spatio-temporal variations over the six-year study period were examined and descriptive groundwater-vegetation associations developed by overlaying a water table depth map onto a vegetation index map derived from MODIS. The results indicate that the water table depends on the local topography, localized geological settings, and human activities such as reclamation, with fluctuations occurring at annual and monthly scales as a function of precipitation and potential evapotranspiration. Locations where the water table is closer to the surface tend to have more dense and productive vegetation. The water table depth is more closely associated with vegetative density in meadowlands than in transitional zones, and only poorly associated with vegetation in sandy dunes

World Atlas of Desertification - Introductory Brochure

The brochure introduces the concept of the World Atlas of Desertification which relies on converging evidence of combined human-environment processes pointing out that land degradation cannot be modeled satisfactorily at global scales.The introductory brochure provides a short overview of the main land degradation issues, through illustration of a number key global datasets and some case study examples that reflect the global patterns and pathways to solutions. The brochure start with highlighting the human dominance that drives global environmental changes. The consequences of feeding a growing population include agriculture expansion and intensification, illustrated by maps and data on irrigation and nutrient use. Aridity and drought are important phenomena aggravating the already present human pressures on the environment. Other pressure patterns playing at global scale are illustrated with examples from China, India, S. America and the Sahel, along with a forward view on solutions.JRC.H.5-Land Resources Managemen

Quantitative Assessment of Desertification Using Landsat Data on a Regional Scale – A Case Study in the Ordos Plateau, China

Desertification is a serious threat to the ecological environment and social economy in our world and there is a pressing need to develop a reasonable and reproducible method to assess it at different scales. In this paper, the Ordos Plateau in China was selected as the research region and a quantitative method for desertification assessment was developed by using Landsat MSS and TM/ETM+ data on a regional scale. In this method, NDVI, MSDI and land surface albedo were selected as assessment indicators of desertification to represent land surface conditions from vegetation biomass, landscape pattern and micrometeorology. Based on considering the effects of vegetation type and time of images acquired on assessment indictors, assessing rule sets were built and a decision tree approach was used to assess desertification of Ordos Plateau in 1980, 1990 and 2000. The average overall accuracy of three periods was higher than 90%. The results showed that although some local places of Ordos Plateau experienced an expanding trend of desertification, the trend of desertification of Ordos Plateau was an overall decrease in from 1980 to 2000. By analyzing the causes of desertification processes, it was found that climate change could benefit for the reversion of desertification from 1980 to 1990 at a regional scale and human activities might explain the expansion of desertification in this period; however human conservation activities were the main driving factor that induced the reversion of desertification from 1990 to 2000

Historical Trends in Air Temperature, Precipitation, and Runoff of a Plateau Inland River Watershed in North China

Understanding historical trends in temperature, precipitation, and runoff is important but incomplete for developing adaptive measures to climate change to sustain fragile ecosystems in cold and arid regions, including the Balagaer River watershed on the Mongolian Plateau of northeast China. The objective of this study was to detect such trends in this watershed from 1959 to 2017. The detection was accomplished using a Mann-Kendall sudden change approach at annual and seasonal time scales. The results indicated that the abrupt changes in temperature preceded that in either runoff or precipitation; these abrupt changes occurred between 1970 and 2004. Significant (α = 0.05) warming trends were found at the minimum temperatures in spring (0.041 °C a−1), summer (0.037 °C a−1), fall (0.027 °C a−1), and winter (0.031 °C a−1). In contrast, significant decreasing trends were found in the precipitation (−1.27 mm a−1) and runoff (−0.069 mm a−1) in the summer. Marginally increasing trends were found in the precipitation in spring (0.18 mm a−1) and fall (0.032 mm a−1), whereas an insignificant decreasing trend was found in the runoffs in these two seasons. Both precipitation and runoff in the wet season exhibited a significant decreasing trend, whereas in the dry season, they exhibited a marginally increasing trend. Sudden changes in spring runoff and sudden rises in temperature are the main causes of sudden changes in basin rainfall

Staple Economies and Social Integration in Northeast China: Regional Organization in Zhangwu, Liaoning, China

The emergence of specialized mobile herding is long been thought to have taken place in Northeast China during the Late Bronze Age (1200 to 600 BCE). It is theorized that the interaction between specialized herders and sedentary farmers was the catalyst for increased social complexity in the region. However, in Northeast China there is little direct settlement and subsistence evidence which appears to indicate the emergence of mobile pastoralism. Therefore, theories based on the interaction between herders and farmers remain tenuous. This research is designed to answer two questions. Did reliance on grazing animals and residential mobility increase in some Late Bronze Age communities located in areas where such subsistence strategies would have been attractive alternatives to grain cultivation under warming and drying conditions? Does such a subsistence shift, if documented, show the artifactual evidence and settlement patterning consistent with economic complementarity? This dissertation outlines the changes in settlement patterns of 173 square kilometer region from 4500 BCE to 1200 CE. The Early and Late Bronze Age (2000 to 1200 BCE and 1200 to 600 BCE) is given special attention because this is when this substantial economic change is thought to have taken place. During the Bronze Age locational evidence and use-wear evidence is taken in concert to evaluate the notion of Late Bronze Age specialized mobile herders either dominating the landscape or part of a settlement system which includes sedentary farmers. Results from this study call into question the emergence of specialized herders during the Late Bronze Age. Despite environmental conditions that would be conducive to herding economies and a warmer and dryer climate from the Early to Late Bronze Age, this dissertation finds evidence that local communities favored a mixed economy throughout the Bronze Age. The local environmental conditions tempered the degree to which communities carried out certain economic practices. However, economic specialization, which was previously thought to have characterized the region, does not appear to be at all consistent with the evidence

Procjena korištenja zemljišta i preobrazbe zemljišnog pokrova i urbane dinamike koristeći viševremenske satelitske podatke

Assessment of Land use and land cover (LULC) transformations at different spatial levels is crucial in several areas, including protection of the environment, resource utilization, planning and sustainability. The present work is an attempt to carry out a detailed study of LULC transformations and to analyze urban areas in Srinagar city (India) using multi-temporal Landsat satellite data for the year 1995 to 2019. Seven different LULC classes were delineated for the selected periods by a supervised method using maximum likelihood classifier algorithm in ERDAS Imagine 14. The findings indicate that over the specified periods substantial changes have occurred in terms of LULC. Overall seven categories were identified and, throughout studies, three trends of LULC change were observed (1) continuous expansion of the area under the class of built-up, barren, horticulture (2) agriculture, water and marshy class are continuously decreasing (3) increase (1995–2010) and decrease (2010–2019) in forest classes between two periods. During the study period, in built-up (+), horticulture (+), agriculture (–) water (–) and marshes (–) most significant changes have been observed, referencing to change in percentage within each class, the maximum variability was observed in built-up (148.07%), horticulture (40.87%), marshes (–58.37%), water (–22%) and agriculture (–35.38%). For quantitative assessment changes Land Consumption Rate (LCR) and Land Absorption Coefficient (LAC) were introduced. The overall research scenario shows that the LULC transition in the city is very evident. The rapid change of LULC in the ecologically sensitive Srinagar city is driven mainly by anthropogenic sources and has a negative environmental influence.Procjena korištenja zemljišta i preobrazbe zemljišnog pokrova (LULC) na različitim prostornim razinama važna je u nekoliko područja uključujući zaštitu okoliša, iskorištavanje prirodnih izvora, planiranje i održivost. U ovom radu pokušava se provesti detaljna studija LULC preobrazbi i analizirati urbana područja u gradu Srinagar (Indija) koristeći viševremenske satelitske podatke Landsat za razdoblje od 1995. do 2019. godine. Iscrtano je sedam različitih LULC klasa za odabrano razdoblje uz pomoć nadzirane metode koristeći algoritam klasifikatora najveće vjerojatnosti u ERDAS Imagine 14. Rezultati ukazuju na to da su se u određenim razdobljima dogodile znatne promjene u smislu LULC-a. Svih sedam kategorija je identificirano te su kroz studije promatrana tri trenda izmjene LULC-a (1) stalno širenje područja u klasi izgrađenosti, neplodnosti, hortikulture (2) poljoprivreda, vode i močvarno tlo se stalno smanjuju (3) porast (1995–2010) i smanjenje (2010–2019) u klasi šuma između dva razdoblja. Tijekom razdoblja provođenja studije, u klasi izgrađenosti (+), hortikulture (+), poljoprivrede (–) voda (–) i močvarnog tla (–) opažene su najznačajnije promjene izražene u postocima unutar svake klase, najveća varijabilnost je uočena u klasi izgrađenosti (148,07%), hortikulture (40,87%), močvarnog tla (–58,37%), vode (–22%) i poljoprivrede (–35,38%). U svrhu kvantitativne procjene promjena uvedene su stopa korištenja zemljišta (LCR) i koeficijent apsorpcije zemljišta (LAC). Sveukupan istraživački scenarij pokazuje da je LULC tranzicija u gradu vrlo očita. Brze izmjene LULC-a u ekološki osjetljivom gradu Srinagaru vođene su uglavnom antropogenim izvorima te imaju negativan utjecaj na okoliš

Procjena korištenja zemljišta i preobrazbe zemljišnog pokrova i urbane dinamike koristeći viševremenske satelitske podatke

Assessment of Land use and land cover (LULC) transformations at different spatial levels is crucial in several areas, including protection of the environment, resource utilization, planning and sustainability. The present work is an attempt to carry out a detailed study of LULC transformations and to analyze urban areas in Srinagar city (India) using multi-temporal Landsat satellite data for the year 1995 to 2019. Seven different LULC classes were delineated for the selected periods by a supervised method using maximum likelihood classifier algorithm in ERDAS Imagine 14. The findings indicate that over the specified periods substantial changes have occurred in terms of LULC. Overall seven categories were identified and, throughout studies, three trends of LULC change were observed (1) continuous expansion of the area under the class of built-up, barren, horticulture (2) agriculture, water and marshy class are continuously decreasing (3) increase (1995–2010) and decrease (2010–2019) in forest classes between two periods. During the study period, in built-up (+), horticulture (+), agriculture (–) water (–) and marshes (–) most significant changes have been observed, referencing to change in percentage within each class, the maximum variability was observed in built-up (148.07%), horticulture (40.87%), marshes (–58.37%), water (–22%) and agriculture (–35.38%). For quantitative assessment changes Land Consumption Rate (LCR) and Land Absorption Coefficient (LAC) were introduced. The overall research scenario shows that the LULC transition in the city is very evident. The rapid change of LULC in the ecologically sensitive Srinagar city is driven mainly by anthropogenic sources and has a negative environmental influence.Procjena korištenja zemljišta i preobrazbe zemljišnog pokrova (LULC) na različitim prostornim razinama važna je u nekoliko područja uključujući zaštitu okoliša, iskorištavanje prirodnih izvora, planiranje i održivost. U ovom radu pokušava se provesti detaljna studija LULC preobrazbi i analizirati urbana područja u gradu Srinagar (Indija) koristeći viševremenske satelitske podatke Landsat za razdoblje od 1995. do 2019. godine. Iscrtano je sedam različitih LULC klasa za odabrano razdoblje uz pomoć nadzirane metode koristeći algoritam klasifikatora najveće vjerojatnosti u ERDAS Imagine 14. Rezultati ukazuju na to da su se u određenim razdobljima dogodile znatne promjene u smislu LULC-a. Svih sedam kategorija je identificirano te su kroz studije promatrana tri trenda izmjene LULC-a (1) stalno širenje područja u klasi izgrađenosti, neplodnosti, hortikulture (2) poljoprivreda, vode i močvarno tlo se stalno smanjuju (3) porast (1995–2010) i smanjenje (2010–2019) u klasi šuma između dva razdoblja. Tijekom razdoblja provođenja studije, u klasi izgrađenosti (+), hortikulture (+), poljoprivrede (–) voda (–) i močvarnog tla (–) opažene su najznačajnije promjene izražene u postocima unutar svake klase, najveća varijabilnost je uočena u klasi izgrađenosti (148,07%), hortikulture (40,87%), močvarnog tla (–58,37%), vode (–22%) i poljoprivrede (–35,38%). U svrhu kvantitativne procjene promjena uvedene su stopa korištenja zemljišta (LCR) i koeficijent apsorpcije zemljišta (LAC). Sveukupan istraživački scenarij pokazuje da je LULC tranzicija u gradu vrlo očita. Brze izmjene LULC-a u ekološki osjetljivom gradu Srinagaru vođene su uglavnom antropogenim izvorima te imaju negativan utjecaj na okoliš