本发明提供了一种封顶固坡锁边综合治理流动沙丘的方法，包括沙丘封顶、固坡和锁边。封顶是将覆网覆盖在沙丘顶部，保护了沙丘顶部原始形态特征，降低了沙丘区域整体风速，减小沙丘移动速率；固坡为一种固定沙丘边坡的固沙方格，可以有效防止沙埋和风蚀，降低地表风速，利于形成结皮及植被生长，促进沙丘边坡生态系统恢复，锁边为在丘间地设置三道阻沙栅栏，既起到拦截沙源，降低固坡措施及丘间地被沙埋，又降低了丘间地风速，保护了丘间地生态系统，本发明提供的封顶固坡锁边模式有效的阻止风沙活动，固定流动沙丘，从根本上治理了沙害，保护了生态，并且可持续，易于大面积推广应用。

Various remote-sensing methods are available to estimate soil moisture, but few address the fine spatial resolutions (e.g. 30-m grid cells) and root-zone depth requirements of agricultural and other similar applications. One approach that has been previously proposed to estimate fine-resolution soil moisture is to first estimate the evaporative fraction from an energy balance that is inferred from optical and thermal remote-sensing images [e.g. using the Remote Sensing of Evapotranspiration (ReSET) algorithm] and then estimate soil moisture through an empirical relationship to evaporative fraction. A similar approach has also been proposed to estimate the degree of saturation. The primary objective of this study is to evaluate these methods for estimating soil moisture and degree of saturation, particularly for a semi-arid grassland with relatively dry conditions. Soil moisture was monitored at 28 field locations in south-eastern Colorado with herbaceous vegetation during the summer months of 3 years. In situ soil moisture and degree of saturation observations are compared with estimates calculated from Landsat imagery using the ReSET algorithm. The in situ observations suggest that the empirical relationships with evaporative fraction that have been proposed in previous studies typically provide overestimates of soil moisture and degree of saturation in this region. However, calibrated functions produce estimates with an accuracy that may be adequate for various applications. The estimates produced by this approach are more reliable for degree of saturation than for soil moisture, and the method is more successful at identifying temporal variability than spatial variability in degree of saturation for this region. Copyright (C) 2015 John Wiley & Sons, Ltd.

Concentrations of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn) and lead (Pb) in dune sands from six urban and suburban Matanzas (Cuba) resorts and Varadero beach were estimated by X-ray fluorescence analysis. Ranges of metal contents in dune sands show a strong variation across the studied locations (in mg/kg(-1)): 20-2964 for Cr, 17-183 for Ni. 17-51 for Cu, 18-88 for Zn and 5-29 for Pb. The values of contamination factors and contamination degrees how that two of the studied Matanzas's resorts (Judio and Chirry) are strongly polluted. The comparison with Sediment Quality Guidelines shows that dune sands from Judio resort represent a serious risk for humans, due to polluted Cr and Ni levels, while sands from the rest of the studied resorts, including Varadero beach, do not represent any risk for public use. (C) 2015 Elsevier Ltd. All rights reserved.

Background: Obesity and other adverse health outcomes are influenced by individual-and neighbourhood-scale risk factors, including the food environment. At the small-area scale, past research has analysed spatial patterns of food environments for one time period, overlooking how food environments change over time. Further, past research has infrequently analysed relative healthy food access (RHFA), a measure that is more representative of food purchasing and consumption behaviours than absolute outlet density. Methods: This research applies a Bayesian hierarchical model to analyse the spatio-temporal patterns of RHFA in the Region of Waterloo, Canada, from 2011 to 2014 at the small-area level. RHFA is calculated as the proportion of healthy food outlets (healthy outlets/healthy + unhealthy outlets) within 4-km from each small-area. This model measures spatial autocorrelation of RHFA, temporal trend of RHFA for the study region, and spatio-temporal trends of RHFA for small-areas. Results: For the study region, a significant decreasing trend in RHFA is observed (-0.024), suggesting that food swamps have become more prevalent during the study period. For small-areas, significant decreasing temporal trends in RHFA were observed for all small-areas. Specific small-areas located in south Waterloo, north Kitchener, and southeast Cambridge exhibited the steepest decreasing spatio-temporal trends and are classified as spatio-temporal food swamps. Conclusions: This research demonstrates a Bayesian spatio-temporal modelling approach to analyse RHFA at the small-area scale. Results suggest that food swamps are more prevalent than food deserts in the Region of Waterloo. Analysing spatio-temporal trends of RHFA improves understanding of local food environment, highlighting specific small-areas where policies should be targeted to increase RHFA and reduce risk factors of adverse health outcomes such as obesity.

Wetland degradation has become a serious global environmental issue. The agriculture and pasture interlaced zone (APIZ) in China is often close to the transition zone between arid and semi-arid regions, and it is extremely ecologically sensitive and vulnerable to global change. However, reports on changes in wetland areas in such zones are rarely available. Here, we analyzed remote sensing images to quantify the historical change in the wetland area of the Huangqihai Lake Basin located in the APIZ in China. The comparison indicated an excellent agreement between the results from remote sensing images and historical records for the lake area. Our results showed that 73% of wetland area had disappeared during 1976-2010. About 86% of the lost wetland area was converted to grassland, forest, and bare fields, while 14% was converted to cropland and built-up land use types. The largest lake in this basin, the Huangqihai Lake, was in a state of contraction during this period, and it has been completely dry since 2008. A large share (54%) of the lost area of the lake has become marshes, while about 97% of the original marsh area within the basin disappeared during 1976-2010. Without substantial efforts in wetland management and protection, this trend in natural wetland degradation is likely to continue. Mapping wetland areas with remote sensing images is an effective approach to providing wetland area information in a spatially and temporarily explicit way in regions where monitoring programs are not available. Such information is useful for understanding wetland degradation processes, and is helpful for investigating the driving forces of wetland degradation. (C) 2014 Elsevier B.V. All rights reserved.

本发明涉及一种冻结粘土空心圆柱试样制样装置，其结构特征是齿状的上下压头卡在对接内筒与外筒之间，位于空心圆柱试样的上下端、外筒利用紧箍圈将其固定，带齿的上压头的正上方是加力杆，它与压样机的压头相接、负责将压力均匀地传递给带齿的上压头。外筒的中间部位是带耳朵的紧箍圈，与一个不锈钢支架相连接。其制样方法是首先将整个装置固定好，将搅拌均匀的湿土分层导入制样筒内，利用压样机对土体进行两头压实。本发明不仅操作简便，节省时间，原理简单，而且能够制成干密度、含水率分布均匀，初始损伤较小、上下表面都是齿状的饱和空心圆柱粘土试样，为进一步研究冻结粘土在复杂应力路径条件下的力学性质提供技术支持。

本发明涉及一种冻土空心圆柱压力室温度控制系统，其特征是压力室外壁上刻有双螺旋冷浴循环槽，冷浴在循环槽中循环降低压力室内部承压传热介质的温度。空心圆柱试样内腔中有一倒U形紫铜管和一温度传感器，三个温度传感器分布于试样外壁的上、中、下位置，中部温度传感器在监测中部位置温度变化的同时，将温度数据反馈给冷浴控制器，上、下部的温度传感器监测相应位置温度的波动。压力室置有上、下冷板，减少压力室内腔承压传热介质与外界的热交换，通过冷板中冷浴的运动，调节压力室温度。本发明能使试样快速降温，保证试样温度在整个试验期间均匀、恒定，不受外界室内温度变化的影响，为揭示冻土在复杂应力路径作用下的力学性质提供了技术保证。

Atmospheric nitrogen (N) deposition is an important component that affects the structure and function of different terrestrial ecosystem worldwide. However, much uncertainty still remains concerning the magnitude of N deposition on grassland ecosystem in China. To study the spatial and temporal patterns of bulk N deposition, the levels of N (NH4+-N and NO3--N) concentration in rainfall were measured at 12 sites across a 1200 km grassland transect in Inner Mongolia, China, and the respective N deposition rates were estimated. The inorganic N deposition rates ranged from 4.53 kg N ha(-1) to 12.21 kg N ha(-1) with a mean value of 8.07 kg N ha(-1) during the entire growing season, decreasing steadily from the eastern to the western regions. Inorganic N deposition occurred mainly in July and August across meadow steppe, typical steppe, and desert steppe, which corresponded to the seasonal distribution of mean annual precipitation. A positive relationship was found between inorganic N deposition and mean annual precipitation (R-2 = 0.54 similar to 0.72, P < 0.0001) across the grassland transect. Annual estimation of inorganic N deposition was 0.67 Pg yr(-1) in Inner Mongolia, China based on the correlation between N deposition rates and precipitation. N deposition was an important factor controlling aboveground biomass and ecosystem respiration, but has no effect on root biomass and soil respiration. We must clarify that we used the bulk deposition samplers during the entire sampling process and estimated the dissolved NH4+-N and NO3--N deposition rates during the entire growing season. Long-term N deposition monitoring networks should be constructed to study the patterns of N deposition and its potential effect on grassland ecosystem, considering various N species, i.e., gaseous N, particle N, and wet N deposition.

本发明公开一种寒区微型蒸渗仪测量系统及其对环境温度的补偿方法，其特征是外围护井通过连接柄与副桶体连接，底部置有可升降的称重底盘，不锈钢桶体放置在称重底盘之上；测量电路板放置在外围护井的副桶体中下部，自动排水泵放置在外围护井副桶体的底部；数据采集器放置在外围护井副桶体的中上部；测量电路板连接在数据采集器上，称重底盘上的称重传感器信号电缆连接到测量电路板上，微处理器控制继电器，继电器控制水泵，将微处理器中嵌入有称重信号的温度补偿程序，在每次对称重传感器的信号进行测量后，会读取温度传感器，取得当前的环境温度，并使用这个温度对称重测量的零点漂移和灵敏度漂移分别进行修正，以减小测量结果受环境温度变化的影响。

Irrigated oases are the main water consumers in arid and semi-arid regions. As plant evapotranspiration (ET) in these regions mainly depends on irrigated water, accurate quantification of evapotranspiration (ET) on the irrigated oases is crucial for allocation and management of irrigation water resources. In this study, we integrated the soil moisture retrieved from Polarimetric L-band Multibeam Radiometer (PLMR) into the Surface Energy Balance System (SEBS) model for improving ET estimates under water stress conditions. The study area is the irrigated oasis in the middle reaches of the Heihe River where airborne and satellite-borne remotely sensed data as well as in situ observations are available through the Heihe Watershed Allied Telemetry Experimental Research (Hi WATER). The main goal of this experiment is to monitor the energy-water exchange between near-surface atmosphere and land surface, and to assess its influencing factors within the oasis-desert ecosystem. The soil moisture data were retrieved using the L-band Microwave Emission of the Biosphere (L-MEB) model fed with the airborne dual-polarized and multi-angular viewing of PLMR. The comparison of soil moisture retrieval from PLMR data with the soil moisture measured by a wireless sensor network (WSN) showed good consistency, with an absolute mean error (ME) <0.004 cm(3) cm(-3) and a root mean square error (RMSE) value <0.05 cm(3) cm(-3). Further, the actual daily evapotranspiration was estimated using the soil moisture integrated (SM-integrated) SEBS algorithm fed with the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) images and soil moisture data retrieved from PLMR data. The sensible heat fluxes and daily evapotranspiration-(ETdatiy) obtained by the SM-integrated SEBS and the original SEBS were compared with the eddy correlation (EC) measurements collected from HiWATER experiment. The results indicate an obvious improvement when soil moisture information is integrated into the SEBS. This method overcomes the weakness of remote sensing based (RS-based) surface energy balance models of overestimating evapotranspiration particularly in semi-arid and arid regions. It shows a prospect that the combination of optical and microwave remote sensing can further improve the RS-based ET estimation. (C) 2015 Elsevier B.V. All rights reserved.