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Plant propagules are crucial flora memory materials in restoration practice. Awakening flora memory from plant propagules (i.e. seeds, root fragments, rhizomes, corms, and tubers) in the translocated topsoil from a donor site is a rapid method for forest restoration on degraded sites globally. However, it remains unclear to what extent manageable measures, such as light reduction and watering, affect flora memory awakening. We employed a quadratic saturation D‐optimal design in a forest topsoil translocation experiment to quantify the effects of light reduction and watering on flora memory awakening. We used the cumulative number and richness of plantlets emerging from plant propagules to represent the extent of flora memory awakening. Our results show that any combinations of light reduction and watering significantly increased both the cumulative number and richness of plantlets across different life forms. Light reduction had a significantly more positive effect on flora memory awakening than watering. Different life forms exhibited different parabolic or positive linear relationships in responses to light reduction and watering. Light reduction of about 60% of the degraded site and watering of about 80% of the donor site resulted in the highest number and richness of plantlets. We concluded that light reduction and watering combinations were effective in kick‐starting the flora memory awakening in a semiarid subtropical forest after topsoil translocation. [ABSTRACT FROM AUTHOR]

Shading and water addition are essential management measures to improve seed germination and early seedling survival; however, little is known about their effects on leaf stoichiometry and nutrient status. We established 90 plant communities with shading and water addition gradients on a rocky hill; leaves of their dominant woody plant species were collected to measure elemental concentrations, and then, stoichiometric variation and nutrient status were analysed. The results showed that the overall effects of shading and water addition significantly altered the concentrations and ratios of nutrient elements; shading largely affected leaf K and P, while water addition mainly affected leaf N and P. The interactions between shading and water addition were significant for most species but disappeared at the community level. Consequently, the nutrient status in leaves was improved by promoting the concentrations and balances of nutrient elements. However, the responses to shading and water addition were marked by species-specific differences, with some plants forming a sensitive group and others distinguished by conservatism. Our findings show that management of the physical environment could improve nutrient element utilization in leaves and alleviate the nutrient limitations. For our site conditions, mild shading (25–35%) and adequate water addition (30 L·m−2) in the early stage of vegetation restoration is recommended to advance community assembly by improving nutrient physiology, directly diminishing the stress of water scarcity and excessive irradiation. These findings explore the underlying mechanisms of shading and water addition that could promote community development and provide guidance for restoration practice. [ABSTRACT FROM AUTHOR]

Yunnan of southwestern China supports an extremely rich biodiversity and various vegetation types dominated by evergreen broad-leaved forest. The floristic composition, species diversity, physiognomy and biogeography of three major types of the evergreen broad-leaved forest in Yunnan were surveyed using 1-ha plots. The three forest types are very diverse in species composition, diversity, physiognomy and biogeography, although they are commonly dominated by species of the families Fagaceae, Theaceae and Lauraceae. The lower montane evergreen broad-leaved forest (LMEB) in southern Yunnan is extremely rich in species and is characterized by a tropical physiognomy and dominated by tropical Asian species, similar to the tropical lower montane evergreen forest commonly in southeast Asia. The semi-wet evergreen broad-leaved forest (SWEB) on plateaus and the upper montane evergreen broadleaved forest (UMEB) in central and northern Yunnan are characterized by a subtropical physiognomy and are dominated by Sino-Himalayan and Chinese endemic species, and are unique in southwestern China. The SWEB and the UMEB should be given high conservation values due to their uniqueness and abundant Chinese endemic species. Especially, the SWEB should be given the highest protection because most remnants of this forest have lost due to heavily human disturbance. Keywords Evergreen broad-leaved forests * Floristic composition * Species diversity * Physiognomy * Biogeography * Conservation * Southwestern China, Introduction The Yunnan Province of southwestern China lies between 21[degrees]09' and 29[degrees] 15' N, 97[degrees]32' and 106[degrees] 12' E (Fig. 1) and occupies an area of 394,100 [km.sup.2]. It has [...]

Film-mulched rock outcrops are a proven way to effectively prevent preferential flow at the rock–soil interface in rocky karst areas, but the impact on rainwater redistribution and maize growth in farmland areas has never been studied. This paper used the dye tracer method at a sprinkling intensity of 1 mm min−1 to study the rainwater redistribution in soils for three different treatments: away from rock (AR), close to rock (CR), and close to film-mulched rock (CFMR). The growth situation of maize (Zea mays L.) according to the different treatments was also studied. It was shown in the study that the rainwater gathered by rock outcrops was mainly confined only within a narrow flow path at the rock–soil interface in the CR treatment, with a preferential flow fraction of 35.78~55.54% and dyeing depth of 15.37~20.00 cm across the three dye application amounts (850 mL, 1700 mL, and 3400 mL) in contrast to the uniform distribution of the rainwater in the soil of the AR treatment, with a preferential flow fraction of 12.31~37.15% and dyeing depth of 6.93~14.00 cm. Interestingly, in the CFMR treatment, there was no preferential flow at the rock–soil interface benefiting from the film's blocking action, and the redistribution of rainwater was mainly based on the matrix flow, with a preferential flow fraction of 24.93~39.62% and dyeing depth of 10.27~18.00 cm, indicating that the film-mulched rock outcrops improved the rock's output capability for gathering rainwater into the surrounding soil. In addition, film-mulched rock outcrops can promote the growth of maize, as indicated by the results for plant height, stem diameter, maximum leaf area, SPAD value, and floral development of maize, which increased in order from AR, CR, to CFMR. Our study suggests that film-mulched rock outcrops have important implications for the efficient use of rainwater and the growth of crops in rocky karst areas, as well as in regions with similar geological characteristics. [ABSTRACT FROM AUTHOR]

Rock outcrops (ROCs), a widespread surface component in karst landscape, play a uniquehydrological role in the infiltration and redistribution of precipitation. We researched theoutcrop runoff infiltration in three directions (i.e., lateral flow into the soil, vertical flowand lateral spread at soil-rock interface) differed greatly at the three sides of theROCs, by applying dye tracer Brilliant Blue FCF, combined with soil loss survey andsoil property measurements. Deep-but-narrow vertical flow was the most commoninfiltration pattern at the uphill sides; long-but-shallow lateral flow towards downslopedominated the ways of outcrop runoff movements at the lateral sides. However, at thedownhill sides, the vertical flow at soil-rock interface was quantitatively equal tothe lateral flow to soil. The difference of outcrop runoff infiltration at the threesides of ROCs may help to reveal the mechanisms of soil erosion as well as rocks’dissolution and biodiversity in a karst environment. Besides, ROCs exert importantfunction in the dynamics of soil stored in between ROCs, especially for soil moisturespatial patterns (SMSP) and its temporal stability. that where ROCs emerged, soilmoisture displayed higher spatial heterogeneity than reported from other terrestrialecosystems, but this area also maintained high temporal stability in the SMSP, as indicatedby the low standard deviation of relative difference σ(δi) and highly significantSpearman rank correlation (rs) found. Linear-fitting analysis demonstrated thefeasibility of using a single representative location to estimate large-scale soil waterconditions in karst rocky ecosystems (R2-values ≥ 0.88). More importantly, thespatiotemporal dynamics of SMSP were apparently driven by the joint effects of soildepth, vegetation, and precipitation. The SMSP was markedly homogeneous andstable in the deep soil layer, as well as during the rainy season; however, with theonset of the dry season, the vegetation tended to induce a temporary change in theroot-zone SMSP. Our study suggests that the multifactor-influenced soil moistureand high temporal stability of SMSP offer both a challenge and an opportunity forbetter understanding the hydrological models and dynamics of rocky ecosystems. [ABSTRACT FROM AUTHOR]

Jinshajiang dry-hot volley has the characteristics of extremely hot and dry climate due to its specific local climate, where universally exists moisture deficit and the problem of soil water environment of artificial vegetation becomes more serious than other arid and semi-arid areas. The environmental determination in the typical sector of dry-hot volley Yuanmou showed that the existed arboreous forests evidently showed the characteristics of soil drying. Soil was short of moisture for a long term. In November after the rain season was over, soil water content in two-meter-deep soil layer was only 15% (equal to 35% of field capacity). Later on, soil water content continued decreasing and reached the lowest point in May (9%), which was near to wilting moisture of trees (the wilting moisture of surface eroded dry red soil of Yuanmou was 9.0%). As a result, trees grew slowly. As for Radonaea wiscosa shrubbery, its soil water content at the same layer was relatively 42.68% higher than that of arboreous trees. The soil moisture of natural grass slope was evidently better than that of arboreous trees and shrubbery, and was 34.36% and 22.22% higher, respectively. This kind of soil drying problem didn't come into notice in the vegetation restoration of Jinshajiang dry-hot volley, which would greatly restrict the sustainable development of artificial vegetation.