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Plant functional traits is connected with vegetation adaptability to the environment. The trade-off between plant functional traits reflects resource reintegration and acquisition under grazing pressures. We summarized the differences of plant functional traits under grazing disturbance, focused on the linkages between grazing disturbance and plant functional traits. We introduced that the variation of plant functional traits resulted from the coordination between plant genetic characteristics and environmental filtration, summarized the effects of grazing on nutritional and reproductive traits, and noted that plants could use survival and reproductive strategies to adapt to the grazing disturbance. We mainly focused on the effects of grazing on plant population, community and ecosystem. The expression of plant functional traits was different under grazing disturbance. Therefore, plant functional traits could be used as indicators to explain population growth and reproduction, community assembly, and ecosystem function. In order to better serve the ecological environment of grassland with plant functional traits, reasonable grazing resis-tant species could be screened according to plant functional traits. Based on life history characteristics of grassland plant population, the scientific grazing mechanism should be formulated, and the responses of plant functional traits and resource allocation to grazing disturbance should be conducted from the perspective of individual-based level in the future.植物功能性状的表达和植被环境适应性相关,植物功能性状之间的权衡变化体现了植物在放牧胁迫下资源的重新整合和获取。本文总结了放牧干扰下植物功能性状表达的差异性,着重将放牧干扰与植物功能性状相结合,介绍了植物功能性状的变异来源是植物遗传特征与环境过滤相互协调的结果,归纳了放牧对植物营养性状、繁殖性状的影响,以及植物可以通过调整生存和繁殖策略以适应放牧干扰。本文集中于放牧对植物种群、群落和生态系统的影响。不同放牧干扰下植物功能性状的表达具有差异性,因此植物功能性状可作为解释种群生长和繁殖、群落构建过程和生态系统功能的指标。为使植物功能性状的研究更好地服务于草地生态环境,可依据植物功能性状筛选合理的草地抗牧物种;依据草地植物种群的生活史特征,制定科学的放牧机制;以植株为整体综合考虑植物功能性状变化,提出放牧研究中植物功能性状的发展方向。.

Litter crusts are integral components of the water budget in terrestrial ecosystems, especially in arid areas. This innovative study is designed to quantify the ecohydrological effectiveness of litter crusts in desert ecosystems. We focus on the positive effects of litter crusts on soil water holding capacity and water interception capacity compared with biocrusts. Litter crusts significantly increased soil organic matter compared to biocrusts and bare lands, by 2.4 times and 3.8 times, respectively. Higher organic matter content resulted in increased soil porosity and decreased soil bulk density. Meanwhile, soil organic matter can help to maintain maximum infiltration rates. Litter crusts significantly increased the water infiltration rate under high water supply. Our results suggested that litter crusts significantly improve soil properties, thereby influencing hydrological processes. Litter crusts play an important role in improving hydrological effectiveness and provide a microhabitat conducive to vegetation restoration in dry sandy ecosystems.

The degradation of soil and vegetation substantially damages ecosystem functions. Litter crusts play an active role in the vegetation restoration and management in desert ecosystems. In this study, the effects of litter crusts on surface microhabitats and species formation on sandy land were studied in the wind-water erosion crisscross region in the Mu Us Desert, northwest China. Soil microhabitat features including moisture, temperature, and organic matter content were measured in different positions of litter crusts and bare sand, seedling species richness, and total seedling number of all species were recorded in litter crusts on the sand's surface. The results showed that there were significant differences between litter crusts and bare sand in terms of soil moisture, temperature, organic matter content, and light intensity. Compared with that of bare sand, soil moisture below litter crusts was increased by an average of 17.0% overall, soil organic matter content was increased by 77.5% at the 0–5 cm depth and by 80.8% at the 5–10 cm depth. Litter crusts decreased soil temperature and light intensity by an average of 16.6% and 31.6%, respectively. Seedling species richness and total seedling number of all species were significantly higher in litter crusts than those in bare sand. Our findings revealed that litter crusts modify the surface microhabitats of sand by maintaining soil moisture, regulating soil temperature, increasing soil nutrients, and reducing light intensity, thus promoting species establishment in the wind-water erosion crisscross region.

23 Pags.- 7 Figs. The definitive version is available at: https://onlinelibrary.wiley.com/journal/10991085, Soil water content (SWC) is a key factor for successful vegetation restoration in arid and semiarid regions, and vegetation has significant influences on the spatial patterns and temporal dynamics of SWC. The aim of this study was to investigate the temporal stability of SWC under different restored grasslands in an arid hilly area of Central China. SWC was measured in the 0‐ to 300‐cm soil profile in the natural grassland (Stipa capillata) and three typical planted grasslands (Medicago sativa, Agropyron cristatum, and Caragana korshinskii) over two growing seasons (from June to October 2015 and 2016) under natural rainfall conditions. The results showed that the mean SWC in the natural grassland was approximately 30% higher than those in the planted grasslands. The SWC consumption of the planted legume grasslands in the deepest soil layers (below 200 cm) was higher than that of the natural grassland, owing to the deep root system of the legumes. Both natural and planted grasslands had low SWC temporal stability in the top soil layers (0–50 cm), whereas more stable conditions were gradually observed with increasing the soil depth. The mean value of the mean relative differences of SWC in natural grassland (ca. 15%) was lower than that in the planted grasslands (A. cristatum grasslands) and much lower than that in the scrubland, highlighting the stronger temporal stability of SWC in the natural grassland. In conclusion, natural grassland could maintain higher and stable SWC and is recommended to be used for achieving sustainable vegetation restoration in arid and semiarid regions., This research was funded by the National Natural Science Foundation of China (NSFC41722107, 41525003, 41390463), the West Light Foundation of the Chinese Academy of Science (XAB2015A04), the Youth Innovation Promotion Association of the Chinese Academy of Sciences (2011288), and the Youth Talent Plan Foundation of Northwest A & F University (2452018025), and Open Project Program of Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration of North‐western China/Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in North‐western China of Ministry of Education (2017KF002, 2018KF05).

How to understand the interactive influence of environmental changes on the total grasshopper density (TGD) becomes an urgent issue in grassland ecosystems. Large-scale studies are ideal for assessing the relative contributions of multiple factors on grasshopper community dynamics. Using data from 634 sites, linkages of community habitats (plant functional groups (PFGs), vegetative litter (VT) and soil types (ST)) and grasshopper occurrence were studied in a farming-pastoral zone across Inner Mongolia. Each of the three primary grassland ecosystem drivers influenced total grasshopper density. The absence of VT (VTabsence) can decrease the total grasshopper density by degrading the habitat conditions. Similarly, grasshopper communities prefer to feed on legumes and forbs rather than grasses due to the plant-trait variance in PFGs. Moreover, total grasshopper density was driven by complex interactions, caused by PFGs, soil types and vegetation litter. Our results improve the understanding of where grasshoppers might occur and provide helpful strategies to prevent the outbreak of grasshoppers.

Afforestation as an effective measure to control soil erosion has achieved remarkable effects in northern China. However, large scale of artificial afforestation can increase soil water consumption and induce soil desiccation in arid and semi-arid areas. This study analyzed the variations of soil water storage following the conversion of croplands into forests with different species and stand ages on the Loess Plateau. Three most common artificial forests dominated by Salix matsudana, Populus cathayana, and Sophora japonica with stand ages of 5, 10, and 15 years were investigated to determine the variations in soil water storage. The results showed that soil water storage decreased with increasing afforestation ages and soil depth. Salix matsudana mainly consumed shallow soil water (0–100 cm), P. cathayana mainly consumed deep soil water (100–150 cm), while S. japonica had relatively lower water consumption than the other two species. Converting cropland into forest resulted in a significant water deficit. Soil water deficit in the 0–100 cm soil profiles was significantly higher under S. matsudana than under the other two artificial forests. Severe soil water depletion and obvious soil desiccation occurred after 12 years of afforestation. Therefore, artificial forests with less water consumption, e.g. S. japonica, should be given priority in future afforestation practice. To maintain the sustainability of vegetation, changes in land-use patterns should be considered after 12 years of afforestation.

Litter crusts are integral components of the water budget in terrestrial ecosystems, especially in arid areas. This innovative study is to quantify the ecohydrological effectiveness of litter crusts in desert ecosystems. We focus on the positive effects of litter crusts on soil water holding capacity and water interception capacity compared with biocrusts. Litter crusts significantly increased soil organic matter, which was 2.4 times the content in biocrusts and 3.84 times the content in bare sandy lands. Higher organic matter content resulted in increased soil porosity and decreased soil bulk density. Meanwhile, soil organic matter can help to maintain maximum infiltration rates. Litter crusts significantly increased the water infiltration rate under high water supply. Our results suggested that litter crusts significantly improve soil properties, thereby influencing hydrological processes. Litter crusts play an important role in improving hydrological effectiveness and provide a microhabitat conducive to vegetation restoration in dry sandy ecosystem.

Desertification is one of the major issues in global environmental change, and it is of great concern to scientists and policy‐makers in the world. Litter crusts can be of great importance for the restoration and management of desert ecosystems. The formation of litter crusts and its ecological effects on desert surface microhabitats were studied in a wind–water erosion crisscross desert region. It was found that litter crusts, especially the four‐year litter crusts, exhibited a better soil storage capacity and temperature regulating ability when compared to the bare land, biocrusts, and two‐year litter crusts; the four‐year litter crusts significantly increased soil total porosity, soil water storage, and soil organic carbon content, but reduced soil bulk density. Furthermore, species richness, coverage, and plant height of seedlings in litter crusts were significantly greater than those in bare land and biocrusts. Although the bare land had the greatest total number of seedlings, the survival rate of seedlings was lowest there. Our findings revealed that litter crusts had significantly positive effects on soil moisture, soil temperature, soil physicochemical properties, and seedling establishment. The multifunctional ecological effects of litter crusts are more positive than lichen‐ and moss‐dominated biocrusts in desert ecosystems.

To evaluate the effects of different forest plantations on rainfall redistribution, we measured throughfall, stemflow, interception loss, surface runoff and soil loss from July 2004 to September 2005 in the three types of forest plantations Eucommia ulmoides, Vernicia fordii and Pinus massoniana. The results showed that differences in throughfall and stemflow between the three forest plantations were significant (p 120 cm than in the other forests, but the difference was not significant between E.ulmoides and V.fordii. Moreover, the difference in throughfall at stem distances 60-120 em was not significant between the different forest plantations. For E.uhnoides, throughfall under the peripheral crown part was 16.1% higher than that close to the stem. In contrast to E.uhnoides, Rmassoniana had 26-8% lower throughfall under the peripheral crown part than close to the stem. No significant difference was found in throughfall for the various stem distances underneath V.fordii. Stemflow in E.ulmoides was 2-3 times higher than in the other forests (p < 0.01). Interception loss accounted for 19.9% of gross rainfall for E.ulmoides, 20.8% for V.fordii and 27.2% for Rmassoniana. Surface runoff and soil loss differed considerably among the three types of forest plantations. Annual runoff and total soil loss were lowest in the Pmassoniana forest and highest in the V.fordii forest. This study indicated that P.massoniana, as a reforestation tree species, had the most positive effect on soil and water conservation among the three forest plantations. Copyright (c) 2008 John Wiley & Sons, Ltd.

The stability and function of a soil ecosystem depends on the cycling of nutrients by the soil microbial community. To evaluate the effects of regenerating forest cover on the function of microbial community, the differences of four forest restoration approaches, including plantations of slash pine, Chinese fir, tea-oil camellia and natural secondary forest, in soil microbial community size, activity and metabolic diversity were measured by microbial biomass and metabolic diversity (BIOLOG) assays in a hilly red soil region, Southern China. Native soils were sampled and assessed with 0-20 and 20-40 cm layers. Results showed that significant differences (p < 0.05) were found in soil microbial biomass among four forest restoration approaches. It was highest in the soil of natural secondary forest, medial in the plantations of tea-oil camellia and Chinese fir and the least in slash pine plantation. Principal component analysis (PCA) further revealed consistent differences of the metabolic diversity patterns in 0-20 cm soil, but not for Chinese fir plantation, tea-oil camellia plantation and natural secondary forest in 20-40 cm soil. Average well colour development (AWCD) and indices of richness and diversity showed significant difference in the four forest restoration approaches. The variable tendency of the indicators was the same as microbial biomass. These suggested that the ability to utilize sole-carbon-source and functional diversity (metabolic diversity) for soil microbial community were stronger in natural secondary forest than that in plantations. Altogether, microbial biomass and metabolic diversity patterns in 020 cm soil of natural secondary forest were dominant, comparing with that of three plantations, viz. slash pine plantation, Chinese fir plantation and tea-oil camellia plantation. While in 20-40 cm soil there were no recognizable differences for above indicators among four vegetation types. Factors affecting the structure and function of soil microbial community appeared to be linked closely with artificial tending, soil and water loss, root biomass and litter production. The information gathered from the studies can be used to baseline data for forest restoration projects. (c) 2005 Elsevier B.V. All rights reserved.

Significant differences were found in soil physicochemical and biological effects between various forest restoration approaches of a hilly red-soil region, southern China. Soil quality was the highest in natural secondary forest (0.95), while in sites revegetated with tea-oil camellia (Camellia oleifera), Chinese fir (Cunninghamia lanceolata) and slash pine (Pinus elliottii) and control sites, integrated soil quality indices were 0.68, 0.55, 0.36 and 0.04 respectively. The lower soil quality of plantations and controls resulted from increased disruption of soil physical structure, lower quality litter fall, lower litter fall production, reduction in microbial biomass, decline of microbial function and loss of soil nutrients due to periodically artificial tending and accelerated soil erosion. Improvement in soil physicochemical properties and enhanced soil microbial function at a natural secondary forest site demonstrated the inherent restoration of these soils. Hence, natural restoration, as well as reducing human disturbance, is a better approach to improving soil properties than returning farmland to planted woodlands. Copyright (c) 2005 John Wiley & Sons, Ltd.