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1

Desertification in the light of sedimentological features of dune deposits

100%
Mycielska-Dowgiallo E.
Geographia Polonica
|
1992
|
tom 60
2

Temporal-spatial distribution of sand storms in the Xilim Gol area of Inner Mongolia

86%
Gou M. M., Li G. T., Li X., Zuo H. J.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 2
309-314
The Xilin Gol area is located in central Inner Mongolia, China. It had been a fertile prairie in northern China, but desertification and sand storms have increased in past decades. This study shows the spatial and temporal distribution of sand storms in the Xilin Gol area. The results of the analysis show: (i) Factors such as strong winds (usually beyond seven levels), rain and temperature have an impact on sand storms. The correlation coefficient between sand storm days and strong wind days is 0.89. (ii) There are more sand storm days in the west than in the east. (iii) In the last 30 years, the frequency of sand storms have been consistently decreasing.
3

Changes in soil organic carbon and its density fractions after shrub-planting for desertification control

86%
Liu J.-B., Zhang Y.-Q., Wu B., Qin S.-G., Lai Z.-R.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 2
Planting shrubs on sand land and degraded pasture are two main measures for desertification control particularly in northwest China. However, their effects on soil organic carbon (SOC) and its fractions remain uncertain. We assessed the changes in stocks of SOC, light fraction of SOC (LF–SOC) and heavy fraction of SOC (HF–SOC) after planting Artemisia ordosica (AO, 17 years), Astragalus mongolicum (AM, 5 years) and Salix psammophila (SP, 16 years) in sand land and planting Caragana microphylla (CM, 24 years) on degraded pasture. Results show that: 1) after planting AO, AM and SP on sand land, SOC stocks increased by 162.5%, 45.2% and 70.8%, respectively, and LF–SOC accounted for a large proportion in the increased SOC. Dry weights of LF–SOC, rather than carbon concentrations, were higher in shrublands than that in sand land; 2) after planting CM on degraded pasture, SOC stock decreased by 9.3% and all the loss was HF–SOC in 60–100 cm soil layer where both herbaceous fine root biomass (HFRB) and soil water content (SWC) also decreased. The results indicate that planting shrubs can result in an increase of SOC in sand land, whereas that can lead to a decrease of SOC in degraded pasture. The increase of SOC in sand land mainly bases on the accumulation of dry weight of LF–SOC. The loss of SOC in degraded pasture is caused by the decrease of carbon concentrations of HF–SOC, which can be related to the reduction of HFRB and SWC in deep soil layer. Therefore, shrub-planting for desertification control not always improve the quantity and stability of SOC in northwest China.
4

Influence of grazing exclusion on soil macro-invertebrate diversity in degraded sandy grassland (Inner Mongolia, China)

72%
Liu R.-T., Zhao H.-L., Zhao X.-Y.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 2
In arid and semi-arid areas, heavy grazing combined with climate change cause land degradation (e.g., desertification). Grazing management is essential for ecosystem recovery and desertification control in these areas, including Northern China’s Horqin Sandy Land. However, the recovery of soil faunal community during grazing exclusion is unknown. We examined plant and soil macro-invertebrate community structure together with soil properties in three treatments in a representative degraded Horqin sandy grassland: exclosure for 15 and 10 years (15EX and 10EX) and long-term continuous grazing (CG). The vegetation cover and height increased significantly and soil bulk density decreased significantly along the gradient from CG to 15EX, but there were no significant differences in soil pH, electrical conductivity, organic carbon and total nitrogen. Soil macro-invertebrate abundance, group richness and diversity increased along the gradient from CG to 15EX, with significant differences in invertebrate abundance and group richness between CG and 15EX; there was no significant differences between CG and 10EX. There were no significant differences in soil macro- invertebrate diversity and evenness between these three treatments. These results suggested that grazing exclusion for at least 15 years might be necessary for the recovery of these fauna. The vegetation height and the soil electrical conductivity, organic carbon, and total nitrogen determined the distribution and community structure of soil macro-invertebrates. Some faunal groups lived in specific habitats due to strong adaptation to different management practices. For example, the Thomisidae, Philodromidae, Salticidae, and Rhopalidae tended to live in habitats with tall vegetation. The Lygaeidae, Miridae, Teneberionidae, and Linyphiidae adapted to live in soil with low soil organic carbon and nitrogen (ungrazed grassland).
5

Carbon accumulation in the bulk soil and different soil fractions during the rehabilitation of desertified grassland in Horqin Sandy Land (Northern China)

72%
Li Y., Zhao X., Wang S., Zhang F., Lian J., Huang W., Mao W.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 1
Desertification, which affects more than two-thirds of the world's arid and semi-arid regions, is a significant global ecological and environmental problem. There is a strong link between desertification of the drylands and emission of CO₂ from soil and vegetation to the atmosphere. The Horqin Sandy Land is a severely desertified area in China's agro-pastoral ecotone due to its fragile ecology, combined with unsustainable land management. We estimated changes of organic carbon content in the bulk soil (0–5 cm), in the light-fraction of soil organic matter (based on density fractionation), and in the various particle-size fractions in areas with mobile sand dunes after implementing grazing exclusion (12 and 27 years) and tree and shrub planting (22 and 24 years). Carbon stocks in the bulk soil and all soil density and particle-size fractions increased significantly in the exclosure and plantation plots. The average rates of carbon accumulation in the bulk soil in the exclosure and plantation plots were 16.0 and 17.8 g m⁻² y⁻¹, respectively, versus corresponding values of 2.3 and 7.1 g m⁻² y⁻¹ for the light fraction, 4.3 and 8.0 g m⁻² y⁻¹ for the coarse fraction, 5.0 and 3.4 g m⁻² y⁻¹ for the fine sand, 4.5 and 4.2 g m⁻² y⁻¹ for the very fine sand, and 1.8 and 1.8 g m⁻² y⁻¹ for the silt clay fraction. The older the exclosure and plantation, the more carbon accumulated in the bulk soil and in each fraction. The carbon pool exceeded the level in non-desertified grasslands after 27 years of grazing exclosure and 24 years of the shrub plantation. Our results suggest that both grazing exclusion and planting trees and shrubs can restore desertified grassland, creating a high potential for sequestering soil carbon, but that the plantations appeared to accumulate soil carbon faster than the exclosures.
6
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The use of Pigeon pea (Cajanus cajan) for drought mitigation in Nigeria

58%
Emefiene M. E., Salaudeen A. B., Yaroson A. Y.
International Letters of Natural Sciences
|
2013
|
tom 01
Drought poses one of the most important environmental constraints to plant survival and productivity and by implication-food insecurity in the tropics. Pigeon pea (Cajanus cajan) has the potential of fertilizing the soil thereby improving agricultural production and ensure green environmental and ecosystem stability. Despite the ability of the plant to improve soil fertility and promote greening environment, it has not attracted adequate awareness as a soil improvement plant. This paper highlights the information on the plant in order to intensify awareness for its widespread adoption to achieve the much desired sustainable resource use for greening our economy and environmental management. The successful widespread adoption of the plant will translate to effective drought, desertification and sustainable climate change mitigation approach in Nigeria.
7

A new model for desertification assessment using Geographic Information System (GIS) − a case study, Runiz Basin, Iran

58%
Masoudi M., Jokar P.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 2
The present paper attempts to evolve a new model by considering various indicators of different types of land degradation or desertification, namely, water erosion, soil salinity, vegetation degradation, and lowering of ground water table for finding areas with higher rate of degradation. The Runiz basin, located in the southern Iran, has been selected as a study area to assess the hazard of desertification. The thresholds for the severity classes of indicators were established and then the hazard map for each indicator of types of desertification has been prepared in a GIS. The risk classes of different risk maps were calculated on the basis of classification of risk scores derived by cumulative effect of all the attributes of indicators after overlying them in the GIS. It was possible to distinguish the areas under ‘actual risk’ from areas under ‘potential risk’ of desertification types. Also areas under potential risk were classified to subclasses with different probability level to show a statistical picture of risk in future. The final map of risk of desertification was produced by overlaying all four maps of degradation types. Results show that potential risk areas and areas under actual risk are almost equal, indicating further threat of desertification in future in the half of the region. Also severe condition in the half of region shows environmentally bad situation in the study area. It is hoped that this attempt using GIS will be found applicable for other regions of the world.
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