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Diurnal and seasonal dynamics of soil respiration in desert shrubland of Artemisia Ordosica on Ordos Plateau of Inner Mongolia, China

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Journal of Forestry Research 2007年第3期18卷 231-235页

作者： JIN Zhao QI Yu-chun DONG Yun-she Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China

The diurnal and seasonal dynamics of soil respiration in the A. ordosica shrubland on Ordos Plateau were investigated in the growing season （May-October） of 2006 and their environmental driving factors were also analyzed, Results indicated that diurnal dynamics of soil respiration rate and its temperature dependence showed some discrepancy in two different growth stages （the vegetative growth stage and the reproductive growth stage）. During the vegetative growth stage, the diurnal variation of soil respiration was slight and not correlated with the daily temperature change, but during the reproductive growth stage, the daily respiration variation was relatively large and significantly correlated with the diurnal variation of air and soil temperature. In the growing season, the peak value of soil respiration occurred at July and August because of the better soil water-heat conditions and their optimal deployment in this period. In the shrubland ecosystem, precipitation was the switch of soil respiration pulses and can greatly increase soil respiration rates after soil rewetting. Moreover, the soil respiration rates in the growing season and the air temperature and soil surface water content were closely correlated （p〈0.05） each other. The stepwise regression model indicated that the variation of soil surface moisture accounted for 41.9% of the variation in soil respiration （p〈0.05）.

关键词： Soil respiration shrubland Artemisia ordosica Ordos Plateau

Absence of tree seeds in shrubland stage impeding forest secondary succession in Southern China

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Absence of tree seeds in shrubland stage impeding forest sec...

Anthropogenic impact on the shrubland habitat of the Spiny Babbler,an endemic of Nepal

广东省植物学会第十七期学术研讨会

作者： Chris Zou Department of Natural Resource Ecology and Management Oklahoma State UniversityStillwaterOK 74078USA

Change in land use in Southern China has resulted in retiring over 40 million hectares of degraded grazing and farmlands,which have consequently converted to *** is now the dominant vegetation type in three southeaste... 详细信息

关键词： Seed banks Seed dispersal Degraded grassland shrubland Secondary succession Restoration

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Anthropogenic impact on the shrubland habitat of the Spiny B...

Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

23rd International Ornithological Congress

作者： Tej K.Shrestha Central Department of Zoology Tribhuvan University P.O. Box 6133 Kathmandu Nepal

＜正＞ This paper examines the impact of water use practices on the distribution and status of the Spiny Babbler Turdoides nipalensis in Nepal. Details of required food, vegetation cover and reproductive success are given against the background of a well-documented scenario of present and past habitat changes. Suggestions are made for appropriate habitat management by enhancing escape cover, roosting cover and emergency food resources. This paper also addresses in some detail the impact of agricultural pesticides and pollution on the food resources of the Spiny babbler. A long-term management plan to conserve this Nepal endemic is given, and areas of future research are highlighted.

关键词： shrubland habitat change reproductive success food resources

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Journal of Arid Land 2024年第7期16卷 925-942页

作者： DU Lan TIAN Shengchuan ZHAO Nan ZHANG Bin MU Xiaohan TANG Lisong ZHENG Xinjun LI Yan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Fukang Station of Desert Ecology Chinese Academy of SciencesFukang 831505China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community ***,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem ***,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in *** salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community *** results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total ***,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in *** mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical *** soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness ***,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these ***,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil *** results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

关键词： soil salinization halophytes shrubland climate change biodiversity drylands Northwest China

Impacts of Overgrazing and Reclamation on Soil Resources in Rangeland Ecosystems in Huailai Basin, Hebei, China

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Wuhan University Journal of Natural Sciences 2005年第4期10卷 721-729页

作者： ZHANGHong HEWei-ming JIANGShi-zhong SchoolofResourceandEnvironmentScience SichuanNormalUniversityChengdu610066SichuanChina LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing100093China

The soil constituents and relations between the variation of soil resources and plant communities in three adjacent sites representing the overgrazing, reclamation and comparatively undisturbed communities respectively were quantified and examined in study area in Huailai Basin, Hebei Province, China. There have been significantly greater constituent of C, N, P in the soils of shrubland site. Corg, Ntotal, Navail and Pavail were between 1.18 and 3.90 times more concentrated in the soils of shrubland site in comparison with the other two sites. Although the Ptotal concentration was lower in shrubland soils than in overgrazed rangeland soils, the Pavail concentration, however, was significantly greater in the soils of shrubland site, and increased by 59.1% and even 289.6% in the soils of shrubland site comparing to those in the soils of range-land and millet field sites. Among the three sites, CV exceeding 40% were found for SO4, Cl, and F ion. The CV of organic carbon also exceeded 40% but only in the soils of millet field site. The highest CV were found for F, SO4 ion in the soils of shrubland and overgrazed rangeland sites, while for Cl and SO4 ion in those of millet field site. The results also showed that the introductions of shrubs are of vital importance for the accumulation of soil nutrients and maintenance of soil fertilities, and also for the restoration and reconstruction of desertified ecosystems.

关键词： soil resources rangeland ecosystem overgrazing reclamation shrubland millet field Huailai basin

Landsat Time Series Analysis of Vegetation Changes in Solar Energy Development Areas of the Lower Colorado Desert, Southern California

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Journal of Geoscience and Environment Protection 2016年第2期4卷 1-6页

作者： Christopher Potter CASA Systems 2100 Los Gatos California USA

Land cover change from renewable energy development in southern California is receiving increasing attention due to potential impacts on protected area conservation, endangered species, and greenhouse gas emissions. This study was designed to quantify and map, for the first time, variations desert vegetation canopy density and related growth rates using 30 consecutive years of Landsat satellite image data across the Lower Colorado Desert. The time-series for mean normalized difference vegetation index (NDVI) values sampled from each of the three major land cover types (shrubland, barren sand dune, and developed urban) showed no significant positive or negative trend in vegetation canopy density. Three periods of significant decrease in NDVI were detected during the drought periods of 1989-1990, 2002-2003, and 2013-2015, indicating that annual precipitation has been the main controller of shrubland canopy growth and green cover. shrubland canopy cover has been relatively stable in renewable energy development zones since the mid-2000s. NDVI change in the period after nearly all southern California solar energy developments were initiated (post-2010) could be attributed largely to topographic water flow pathways through canyons and desert washes, both in and around all solar energy development zones.

关键词： Landsat shrubland Solar Energy Development Lower Colorado Desert DRECP