晚熟蟠桃新品种‘瑞蟠24号’

‘瑞蟠24号’是从‘瑞蟠10号’自然实生后代中选出的晚熟蟠桃（Prunus persica var. platycarpa Bailey）新品种。花蔷薇形,有花粉。果实扁平形,平均单果质量226 g,最大406 g;果肉黄白色,硬溶质,风味甜,可溶性固形物含量12.6%。粘核。丰产。果实发育期135 d。     

不同处理方式对蟠桃常温运输及货架期品质的影响

以蟠桃为试材,研究蓄冷剂处理、蓄冷剂+1-MCP和蓄冷剂+乙烯吸收剂处理对常温(25~28℃)运输及货架期间果实品质的影响。结果表明,与纸箱和泡沫箱贮运相比,3种处理方式对降低蟠桃果实呼吸强度、失重率和腐烂率有明显作用,并可延缓果实硬度的降低,保持果实较好的感官品质,其中蓄冷剂处理、蓄冷剂+1-MCP处理可有效降低果实呼吸强度和延缓硬度的下降,蓄冷剂+1-MCP处理、蓄冷+乙烯吸收剂处理对降低果实失重率和腐烂率作用明显。蓄冷剂+1-MCP处理的蟠桃果实常温条件下货架期可延长至7 d。     

长江口崇明岛土地利用方式对滨海土壤中重金属和砷的分布和形态特征的影响

The reclamation of tidal flats has been one of the important approaches to replenish the arable lands in the coastal areas; pollution status of reclaimed soils has received wide attention recently, especially for the study of heavy metals due to the relative high pollutant concentrations in wetlands. To understand the impact of land use change on heavy metal and arsenic(As) geochemistry by the reclamation of wetlands for agriculture, surface soils and soil profiles were collected from the agricultural land reclaimed in the 1990 s and the intertidal flat wetland at Dongtan on Chongming Island in the Yangtze River Estuary, China. The soil samples were analyzed for total concentrations and chemical speciation of chromium(Cr), zinc(Zn), copper(Cu), lead(Pb), nickel(Ni), cadmium(Cd) and As using inductively coupled plasma mass spectrometry(ICP-MS). Results showed that soil properties(salinity, total organic carbon and grain-size distribution) and the concentrations of heavy metals and As in the soils differed under the different land use types. The conversion of wetland to forest had caused obvious losses of all the measured heavy metals. In paddy field and dryland with frequent cultivation, the concentrations of Cr, Zn, Cu, Ni and As were higher when compared to forest land which was disturbed rarely by human activities. Speciation analysis showed that Cr, Zn, Cu, Ni and As were predominated by the immobile residual fraction, while Pb and Cd showed relatively higher mobility. In general, metal(except Ni) and As mobility decreased in the following order: wetland dryland ≥ paddy field forest land, which suggested that the reclaimed soils had lower metal and As mobility than the intertidal flat wetland. The results of this study contribute to a better understanding of the effects of land use on heavy metals and As in the reclaimed soils of the study area and other similar coastal areas.     

Predicting the retreat and migration of tidal forests along the northern Gulf of Mexico under sea-level rise

Tidal freshwater forests in coastal regions of the southeastern United States are undergoing dieback and retreat from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. In many areas, tidal saltwater forests (mangroves) contrastingly are expanding landward in subtropical coastal reaches succeeding freshwater marsh and forest zones. Hydrological characteristics of these low-relief coastal forests in intertidal settings are dictated by the influence of tidal and freshwater forcing. In this paper, we describe the application of the Sea Level Over Proportional Elevation (SLOPE) model to predict coastal forest retreat and migration from projected sea-level rise based on a proxy relationship of saltmarsh/mangrove area and tidal range. The SLOPE model assumes that the sum area of saltmarsh/mangrove habitat along any given coastal reach is determined by the slope of the landform and vertical tide forcing. Model results indicated that saltmarsh and mangrove migration from sea-level rise will vary by county and watershed but greater in western Gulf States than in the eastern Gulf States where millions of hectares of coastal forest will be displaced over the next century with a near meter rise in relative sea level alone. Substantial losses of coastal forests will also occur in the eastern Gulf but mangrove forests in subtropical zones of Florida are expected to replace retreating freshwater forest and affect regional biodiversity. Accelerated global eustacy from climate change will compound the degree of predicted retreat and migration of coastal forests with expected implications for ecosystem management of State and Federal lands in the absence of adaptive coastal management.     

南方平原灌区稻田涝水过程模拟

基于高邮灌区典型区域降雨涝水过程监测,根据灌区特点对水箱模型进行改进,构建了适合于平原稻区稻田涝水过程模拟模型,采用自适应遗传算法对模型参数进行了率定,并对模型在水稻灌区的适应性进行评价.结果表明:稻田水箱模型对稻田涝水过程模拟具有较高精度.率定期,降雨径流模拟值与实测值均方根误差RMSE为0.17~0.28 mm/h,相关系数r大于0.95,模型纳什系数NSE为0.79~0.96.验证期,降雨径流模拟值与实测值之间均方根误差RMSE为0.06~0.29 mm/h,相关系数r超过0.88,模型模拟纳什系数NSE为0.73~0.93;对稻田蓄水深的模拟,均方根误差RMSE为15~20 mm,相关系数均大于0.95,纳什系数NSE为0.84~0.90.因此,改进的稻田水箱模型能够反映稻田的水循环过程,可为南方平原水稻灌区防洪除涝减灾对策的制定提供决策支持.     

高纬寒地不同玉米栽培模式对土壤水分、温度及产量的影响

为探究玉米品种相配套的栽培技术,通过玉米在平作、常规垄作和大垄双行三种模式下的栽培试验,研究其对土壤水分、温度及玉米产量的影响。结果表明:平作比垄作具有较好的保墒作用,但增温效果差;大垄双行不但具有良好的保墒和增温效果,还达到了一定的增产效果,是一种适合高纬寒地的栽培模式。     

秸秆和植被覆盖对滩涂围垦区土壤盐分和肥力性质的影响

为探明不同地面覆盖对滩涂围垦区土壤盐分变化和肥力性质的影响,于2014年5月~2015年5月,在江苏如东东凌垦区开展了秸秆和植被覆盖的田间试验,设置对照(CK,裸地)、15 t/hm~2秸秆覆盖(SM)、植被覆盖(PC,田菁-野生芥菜种植)和植被覆盖结合7.5 t/hm~2秸秆覆盖(PC+1/2SM)4种试验处理。结果表明:(1)与CK处理相比,覆盖处理半年后(12月),SM处理0~40 cm土壤含盐量下降了91.0%以上(P0.05),而PC和PC+1/2SM处理0~40 cm没有明显的降盐效果(P0.05);SM、PC和PC+1/2SM处理1年后滩涂围垦区0~100 cm各土层土壤含盐量均有明显地下降,SM、PC和PC+1/2SM处理0~40和40~100 cm土壤含盐量分别下降了97.0%和83.0%以上,40.0%和30.0%以上,54.0%和33.0%以上;(2)SM和PC+1/2SM处理0~100 cm土壤pH值均显著高于CK和PC处理(P0.05),而CK与PC处理间pH变化没有明显差异;(3)PC和PC+1/2SM处理显著增加了表层(0~20 cm)土壤有机碳、全氮、碱解氮含量及孔隙度,显著降低了表层土壤容重(P0.05),但SM处理对土壤容重、有机碳、全氮、碱解氮、有效磷等均没有明显的影响。因此,相比PC和PC+1/2SM处理,虽然15 t/hm~2秸秆覆盖措施对滩涂围垦区土壤降盐效果更为明显,但综合考虑土壤培肥和降盐效果,种植耐盐植被结合适量秸秆覆盖(如15 t/hm~2秸秆覆盖)是滩涂围垦区降盐改土的重要措施之一。     

三工河流域蟠桃栽培水分管理技术探讨

通过对三工河流域阜康地区典型蟠桃园田间土壤水分监测和适宜灌水量试验研究,探讨蟠桃栽培的水分管理,提出了当地适宜的灌溉方式,为北疆蟠桃栽培管理提供技术参考.     

基于TerraSAR-X/TanDEM-X数据的森林高度反演算法研究

基于RVoG模型,对传统三阶段算法及其改进算法进行研究,以云南省西双版纳州勐腊县为研究区,以TerraSAR-X/TanDEM-X数据为数据源进行森林高度反演算法研究,并结合野外实测数据进行结果验证。结果表明,三阶段改进算法对森林高度反演精度优于传统三阶段算法。三阶段改进算法对天然林高度反演精度较高;三阶段算法对橡胶林高度反演精度较高。     

不同施肥水平对扁穗雀麦种子产量的影响

采用二次回归旋转组合设计,研究了N肥、P肥、K肥和有机肥4因子对扁穗雀麦种子产量的影响,建立了相应的数学模型,结果表明:N肥用量在15.98~19.02 kg/667m2、P肥用量在22.83~27.17 kg/667m2、K肥用量在9.23~10.69 kg/667m2、有机肥用量在2 350.77~2 497.04 kg/667m2时,扁穗雀麦种子产量大于192.5 kg/667m2,是较适宜的处理组合。