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Due to their simple layout and adaptability to various environments, straw checkerboards are widely used to control windblown sand in China. To fully understand the wind proofing and sand-fixing benefits of different board specifications, and to determine the restorative effects of straw checkerboard, we tested different sizes of checkerboard, determined their performance as a windbreak and in trapping shifting sand, and constructed models based on wind tunnel tests, enabling the wind speed flow field to be analysed. We also sampled the soil in areas where straw checkerboards had been established for several years and analysed the trends in soil physical and chemical properties over time. We found that all sizes of straw checkerboard effectively reduced the wind speed near the surface and formed a protected area, with the best protective effect achieved for a one-meter board. All sizes of straw checkerboard effectively intercepted windblown sand to form surface accumulation, with the one-meter board again showing the best performance. The use of a straw checkerboard also effectively improved the physical and chemical properties of soil and promoted ecological restoration. These results indicate that straw checkerboards are a low-cost engineering measure that could play an important role in desertification control and the ecological restoration of sandy land ecosystems.

Plant temperature is an indicator of stomatal conductance, which reflects soil moisture stresses. We explored the relationship between plant temperature and soil moisture to optimize irrigation schedules in a water-stress experiment using Firmiana platanifolia (L. f.) Marsili in an incubator. Canopy temperature, leaf temperature, and stomatal conductance were measured using thermal imaging and a porometer. The results indicated that (1) stomatal conductance decreased with declines in soil moisture, and reflected average canopy temperature; (2) the variation of the leaf temperature distribution was a reliable indicator of soil moisture stress, and the temperature distribution in severely water-stressed leaves exhibited greater spatial variation than that in the presence of sufficient irrigation; (3) thermal indices (Ig) and crop water stress index (CWSI) were theoretically proportional to stomatal conductance (gs), Ig was certified to have linearity relationship with gs and CWSI have a logarithmic relationship with gs, and both of the two indices can be used to estimate soil moisture; and (4) thermal imaging data can reflect water status irrespective of long-term water scarcity or lack of sudden rainfall. OPEN ACCESSForests 2015, 6 3749This study applied thermal imaging methods to monitor plants and develop adaptable irrigation scheduling, which are important for the formulation of effective and economical agriculture and forestry policy.

Plant temperature (Tp) is an important indicator of plant health. To determine the dynamics of plant temperature and self-cooling ability of the plant, we measured Tp in Artemisia ordosica in July, in the Mu Us Desert of Northwest China. Related factors were also monitored to investigate their effects on Tp, including environmental factors, such as air temperature (Ta), relative humidity, wind speed; and physiological factors, such as leaf water potential, sap flow, and water content. The results indicate that: 1) Tp generally changes in conjunction with Ta mainly, and varies with height and among the plant organs. Tp in the young branches is most constant, while it is the most sensitive in the leaves. 2) Correlations between Tp and environmental factors show that Tp is affected mainly by Ta. 3) The self-cooling ability of the plant was effective by midday, with Tp being lower than Ta. 4) Increasing sap flow and leaf water potential showed that transpiration formed part of the mechanism that supported self-cooling. Increased in water conductance and specific heat at midday may be additional factors that contribute to plant cooling ability. Therefore, our results confirmed plant self-cooling ability. The response to high temperatures is regulated by both transpiration speed and an increase in stem water conductance. This study provides quantitative data for plant management in terms of temperature control. Moreover, our findings will assist species selection with taking plant temperature as an index.

This study assessed the influence of rhizocompartment types (i.e., root, rhizosphere soil, root‐zone soil, and intershrub bulk soil) on the diversity of soil microbial communities under desert leguminous plant shrubs. Moreover, the influence and variations of soil physicochemical factors in interactions among leguminous plants, soil, and microbes were investigated. Both 16S rRNA high‐throughput genome sequencing and conventional soil physicochemical index determination were used to characterize both the bacterial diversity and soil physicochemical properties in the rhizocompartments of two Hedysarum species ( Hedysarum mongolicum and Hedysarum scoparium ) in the Mu Us Desert of China. All nutrient indices (except total phosphorus and available phosphorus) in rhizosphere soil were uniformly higher than those in both root‐zone soil and intershrub bulk soil ( p < .05). The bacterial community diversity in the root, undershrub soil (i.e., rhizosphere and root zone), and intershrub bulk soil also showed significant differences ( p < .05). The bacterial community in the root is mainly composed of Proteobacteria, Actinobacteria, Bacteroidetes, Tenericutes, and Chloroflexi, among which bacteria of the Proteobacteria genus are dominant. Root endophyte and rhizosphere soil microbiomes were mainly influenced by soil nutrients, while bacterial communities in root‐zone soil and intershrub bulk soil were mainly influenced by soil pH and NH 4 + ‐N. The rhizocompartment types of desert leguminous plants impose a significant influence on the diversity of soil microbial communities. According to these findings, nitrogen‐fixing rhizobia can co‐exist with nonsymbiotic endophytes in the roots of desert leguminous plants. Moreover, plants have a hierarchical filtering and enriching effect on beneficial microbes in soil via rhizocompartments. Soil physicochemical factors have a significant influence on both the structure and composition of microbial communities in various rhizocompartments, which is derived from the interactions among leguminous plants, soil, and microbes.