基于多源数据和模糊k-均值方法的农田土壤管理分区研究

以近地传感器(EM38)快速获取的土壤表观电导率数据(ECa)、高分遥感影像提取的归一化植被指数(NDVI)和雷达影像提取的后向散射系数为数据源,以滨海滩涂区为研究对象,利用聚类法进行农田土壤管理分区研究.在对不同的数据源进行空间变异分析的基础上,结合滨海滩涂区土壤盐分的空间变异规律,利用非监督分法一模糊k-均值聚类方法进行特征相似性归类,划分不同的管理分区.结果表明,最佳的分区数目为3个.根据每一分区的特点,可以采取相应的管理措施进行土壤改良和农田精确管理.分区结果不但可以指导采样,而且可用于实施变量投入和精确施肥推荐,为样区大面积农田土壤管理提供科学的决策依据.     

岱岳区春季低温发生特点及风险评价

利用岱岳区1981～2010年近30a春季的低温气象资料,分析当地春季晚霜冻发生的特点,对下辖的10个乡镇气象站2006—2010年共5a的气象资料进行插值和年代外推,并进行春季低温风险评价和区划。结果表明：岱岳区3月和4月低温灾害综合风险的分布大致相同,北部和东部山区的祝阳镇、徂徕镇等乡镇（街道）为高度风险区,马庄镇、房村镇等城市近郊为中度风险区,粥店街道、满庄镇、大汶口镇等乡镇（街道）多为轻度风险区。研究结果可为因地制宜制定防灾减灾规划和农业种植规划提供科学依据。     

Suitable climate for rubber trees affected by the South American Leaf Blight (SALB): Example for identification of escape zones in the Colombian middle Magdalena

South American Leaf Blight (SALB), caused by the fungus Pseudocercospora ulei, is the major constraint for rubber tree cultivation in Latin America, continent of origin of the rubber tree. The use of resistant tree cultivars and the identification of escape zones seem to be the best disease control measures. In order to characterize the climate and the pedological parameters in the region of Middle Magdalena, Colombia, we used temperature, relative humidity and annual rainfall records for a 20-year period (1990–2010) from 19 weather stations distributed across the region, together with definitions of the soil units for the area. With the recorded data, we calculated annual and monthly averages of temperature and relative humidity, annual rainfall, annual water balance, annual potential evapotranspiration, number of months with rainfall lower than 50 mm and 100 mm, and number of months with relative humidity lower than 75%. To determine the suitable climate for the rubber crop facing SALB, these results were interpolated through Inverse Distance Weighting with the software ArcGis 9.3 for each variable and their combinations, having as references the plant requirements and the disease escape areas. Regarding the annual rubber tree evapotranspiration requirement, the map showed that the region of Middle Magdalena is suitable for the rubber cultivation. However, La Gloria (Cesar), Regidor (Bolívar) and Gamarra (Cesar) are not suitable for rubber cultivation owing to the high soil hydric deficit (>500 mm). When we considered the rubber tree's requirements, the region was divided into the following types of areas: two unsuitable, two marginal and one suitable. However, considering the disease escape requirements, this region was divided into one unrestricted area and six preferential areas with different restrictions to the SALB control. The most important area of the Middle Magdalena Region is not an escape zone, hence in these areas, the use of highly productive clones resistant to P. ulei is suggested.     

毕节市植烟土壤分析与区划研究

[目的]探讨毕节市不同区域植烟土壤对烟叶品质的影响。[方法]对8个县市的土壤类型、土壤质地、土壤pH、土壤有机质、土壤元素、耕作层的特性进行分析。[结果]毕节市烤烟种植区可划分最适宜区、适宜区、次适宜区和不适宜区。[结论]该研究可为毕节烤烟生产合理布局提供理论依据。     

昆明丘陵地区烤烟气候区划指标研究

在分析昆明地区烤烟气候资源优势及数值模拟温度场基础上,因地制宜地制定了该地区（包括广大丘陵地区）的烤烟气候区划指标。