A comparison of two models with Landsat data for estimating above ground grassland biomass in Inner Mongolia,China

Two models, artificial neural network (ANN) and multiple linear regression (MLR), were developed to estimate typical grassland aboveground dry biomass in Xilingol River Basin, Inner Mongolia, China. The normalized difference vegetation index (NDVI) and topographic variables (elevation, aspect, and slope) were combined with atmospherically corrected reflectance from the Landsat ETM+ reflective bands as the candidate input variables for building both models. Seven variables (NDVI, aspect, and bands 1, 3, 4, 5 and 7) were selected by the ANN model (implemented in Statistica 6.0 neural network module), while six (elevation, NDVI, and bands 1, 3, 5 and 7) were picked to fit the MLR function after a stepwise analysis was executed between the candidate input variables and the above ground dry biomass. Both models achieved reasonable results with RMSEs ranging from 39.88% to 50.08%. The ANN model provided a more accurate estimation (RMSE_r = 39.88% for the training set, and RMSE_r = 42.36% for the testing set) than MLR (RMSE_r = 49.51% for the training, and RMSE_r = 53.20% for the testing). The final above ground dry biomass maps of the research area were produced based on the ANN and MLR models, generating the estimated mean values of 121 and 147 g/m², respectively.     

Impacts of changes in rangeland management laws and policies on grazing flexibility and pastoral livelihoods in Inner Mongolia,China

Inner Mongolia is an autonomous region of China and has a long history of pastoralism. It is a predominately arid and semi-arid region with annual precipitation of 20–500 mm from the west to east. Prior to intervention of modern rangeland management laws and policies, the pastoralists in Inner Mongolia responded to variability in ecological condition and patchiness of rangeland resources via flexible rangeland management. However, since the 1950s, some rangeland management laws and policies have affected the flexibility of rangeland management in Inner Mongolia. This study investigated the impacts of changes of rangeland management laws and policies on grazing flexibility in Inner Mongolia, and discussed whether it is desirable to allow flexibility of grazing management in Inner Mongolia, and what are the possible directions to encourage the flexibility. First, the study investigated the historical and current policies of rangeland management in Inner Mongolia from the perspective of property rights. Second, the study identified and analysed how some of the previous collectivisation and privatisation policies of the rangeland resources and livestock have affected grazing flexibility in this region. Third, this study discussed whether a higher level of flexibility of grazing management is desirable in Inner Mongolia and gave recommendations on the possible directions to encourage the flexibility of grazing management. The study drew on theories of rangeland management in Inner Mongolia, Mongolia and parts of Africa and has increased the understanding of grazing flexibility in Inner Mongolia. It is a step towards more sustainable rangeland management and development in Inner Mongolia.     

内蒙古沙尘气溶胶浓度及其输送特性——朱日和春季情形的个例研究

利用WPS宽范围粒径谱仪对朱日和春季0.01～10μm的沙尘气溶胶观测资料,以及20m梯度塔气象要素资料,对沙尘天气日和非沙尘天气日的气溶胶浓度、谱分布以及输送特性进行了个例研究.结果表明:沙尘气溶胶浓度有明显的日变化特征,不同粒径段粒子的变化特征有所不同;沙尘气溶胶浓度在沙尘天气和非沙尘天气存在较大差别,粒径越大,这种差别越明显;气象要素对沙尘气溶胶浓度的分布有较大的影响,风速、气温、相对湿度与不同粒径段粒子的相关性不同;沙尘暴过程对不同粒径段粒子的输送特性不同,不同粒径段对应的输送距离和输送量有较大差别.     

草原旅游资源深度开发研究——以内蒙古自治区为例

旅游资源是构成旅游业发展的基础，草原旅游资源的合理利用与深度开发具有重要意义。着眼于内蒙古草原旅游现状，通过分析内蒙古草原旅游资源的特征和深度开发的必要性与可行性，提出开发理念、开发模式、区域合作和产品开发方面的设想，尤其基于资源的状况提出3种资源开发模式：依托市场模式、组合集聚模式和依托资源模式。     

内蒙古河套灌区排水干沟微塑料赋存特征及质量估算

陆地径流中微塑料污染因其与人类联系更紧密已越来越受到人们的广泛关注,为分析内蒙古河套灌区排水干沟和总排水干沟微塑料的赋存特征并对其质量进行估算,通过现场采样、密度悬浮法分离、显微镜观察、傅里叶红外光谱测定和比例流量法等,鉴定了河套灌区排水干沟和总排水干沟水体和沉积物中微塑料的丰度分布、形状、颜色、粒径和化学成分,并估算了总排水干沟日输送微塑料的质量.结果表明,河套灌区排水干沟和总排水干沟水体中微塑料丰度值范围为2880~11200 n ·m^-3,沉积物中微塑料丰度值范围为100~292 n ·kg^-1;纤维状为最常见的微塑料形态,分别占据水体和沉积物的34.98%~70.39%和42.24%~58.56%;微塑料颜色以透明为主,分别占据水体和沉积物的46.43%~61.51%和40.41%~57.44%;微塑料粒径以<0.5 mm粒径最多,分别占据水体和沉积物微塑料的46.43%~61.51%和43.27%~54.79%;利用傅里叶红外光谱得出聚乙烯是最常见的类型（43%）,其次是聚苯乙烯（34%）和聚丙烯（16%）;通过估算得出河套灌区总排水干沟每天可向乌梁素海排放的微塑料质量达到116.06 kg,并在乌梁素海积蓄后产生严重的微塑料污染效应.本研究可为内蒙古河套灌区微塑料的污染提供参考和借鉴.     

A grassland ecosystem model of the Xilingol steppe, Inner Mongolia, China

The natural grassland ecosystem of the Xilingol steppe has traditionally been the source of the most productive and highest quality agriculture in northern China. Unfortunately, the area is now experiencing degradation due to resource overuse. In an attempt to forecast grassland production and to sustain the ecosystem, we built a time-dependent simulation model of the ecosystem based on long-range weather forecasts (several weeks to several months). The model incorporated five state variables including above- and belowground biomass, the amount of standing dead plant material, livestock (sheep) weight, and the amount of excrement per unit ground area. Within the model, solar light energy is fixed by grassland vegetation and flows through the other variables via a variety of organism-environment interactions. The model was written using a set of simultaneous differential equations and was numerically analyzed. The values of the time-dependent parameters controlling energy flow were determined based on data accumulated in experiments and field surveys executed at a grassland experimental station located in Xilingol, as well as by reference to related literature. We used daily meteorological data including air temperature and rainfall recorded at the Xilinhot Meteorological Observatory. Simulated results for several stocking densities coincided well with the data of aboveground plant biomass observed at the experimental station in 1990, 1993, and 1997. We obtained reasonable simulation results for five stocking densities, three air temperature patterns, and five rainfall patterns. When a month-long drought, which sometimes occurs in this area, was forecast by a local weather station, a decrease in grassland production was forecast by the model. Such forecasts will assist in the management of livestock, forage preservation, and grassland conservation.     

内蒙古主要作物农田优化灌溉动态预报方法

灌溉是预防或减轻旱灾的有效手段，适时适量灌溉是节约日益匮乏的有限水资源的主要途径之一。从土壤一作物一大气连续体角度出发，根据田间试验资料和气象资料，确定出春小麦、春玉米不同生长阶段土壤水分控制的下限标准，提出了两种作物根系生长动态模拟方程和蒸散系数模拟方程，在土壤水分平衡理论的基础上，建立了预报灌溉日期的方法，并以春小麦、春玉米农田为例进行了检验，结果比较理想。     

发动机燃烧室内壁材料热环境的气动热试验模拟技术研究

利用超声速矩形湍流导管和等离子电弧加热器模拟了发动机燃烧室内流和高超声速飞行器外壁面外流热环境,进行了平板表面冷壁热流测量和燃烧室内壁材料考核试验。结果表明:由于辐射换热的影响,在选取的两个典型来流条件下,发动机燃烧室内流热环境下的冷壁热流比外流热环境下的高出21%和40%,但是冷壁热流的增量基本相当,约为0.70~0.80MW/m²。随着冷壁热流的增加,辐射换热产生的热流增量的影响力会逐渐减小。材料考核时,相同配方的C/SiC复合材料在内流热环境下的表面温度高出约400℃,背面温度高出约90℃,这种差异对于发动机燃烧室内壁面材料考核至关重要,必须在材料考核试验中加以考虑。      

内蒙古草地资源与生态环境

内蒙古自治区是我国三大牧区之一。处在我国北方干旱和半干旱地区，地理位置和在陆地生态系统中的地位十分重要。是内蒙古生态环境保护和建设的主体。但当前草地环境问题十分严峻，危肋着人们生存环境和经济社会的可持续发展，必须加强对其保护和建设。     

中国东北、内蒙古地区茶藨属果树资源的研究

本文对东北、内蒙古地区茶属果树资源进行了调查，初步查明有１９种、２变种、１变型，并对其特征、特性、生境、分布及利用价值进行了研究，总结了驯化栽培的研究结果，提出了开发利用的建议。