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91.
92.
[目的]遥感估算和分析2007年重庆市植被净初级生产力(NPP)。[方法]基于CASA模型,结合SPOT/VEGETATION NDVI S10数据、植被覆盖分类图、气象数据等,对2007年重庆市NPP进行遥感估算,在GIS及RS的支持下,进行数据的前期处理,对2007年重庆市NPP分布状况及年内变化情况进行分析。[结果]NPP平均值为112.343~799.391 g C/m~2,研究区植被净初级生产力区域变化明显,季相差异显著,其中高值主要出现在渝东南、东北区域,低值主要存在于渝西北区域;NPP值夏季(6~8月)﹥春季(3~5月)﹥秋季(9~11月)﹥冬季(12~2月),年内阔叶林植被NPP最高,水生植被NPP生产量最低。[结论]该NPP估算方法能较好地模拟重庆市的NPP及其时空格局,估算结果比较符合实际,能应用于NPP估算项目中。 相似文献
93.
甜瓜结实花初花节位QTL分析 总被引:2,自引:1,他引:2
以WI998为母本(纯雌株、厚皮网纹甜瓜品系),TopMark为父本(雄全同株纯合品系),配置杂交组合,利用单粒传得到171个株系的重组自交系(F2S4)群体构建甜瓜SSR分子标记遗传连锁图谱。该连锁图谱包含19个连锁群,覆盖基因组长度为1 414.2 cM,标记间平均距离为10.2 cM。对结实花初花节位开展QTL分析,共检测到9个QTL,分别分布在第1、9、10、11连锁群上,各QTL的LOD值在2.89 ~ 9.42之间,4个QTL贡献率超过10%。位于第9连锁群的QTL Fp9.4贡献率最大,为18.57%(2010秋季LOD = 9.17);位于第9连锁群的Fp9.3(2010春季8.64%,LOD = 6.44;2010秋季17.99%,LOD = 9.42),位于第10连锁群的Fp10.1(2010春季3.59%,LOD = 2.89;2010秋季6.20%,LOD = 3.43)在两季的位置都很稳定。获得与结实花初花节位紧密连锁(< 10 cM)的8个特异标记(SSR01737、MU141991、TJ105、GCM206、SSR04910、MU173563、NR52、MU146331),为进一步开展QTL精细定位提供参考。 相似文献
94.
应用高光谱数据定量反演查干湖水质参数研究 总被引:2,自引:0,他引:2
湖泊水质下降和富营养化问题日益严重,传统监测方法已经日益不能满足水质监测的需要。该文通过野外高光谱仪器测定查干湖水体反射光谱,分析研究水体反射光谱特征与水质参数叶绿素a含量、透明度和浊度之间的关系,运用多种半经验算法建立反演模型。结果表明:单波段光谱反射率与叶绿素a和浊度的相关系数较小,但与透明度相关系数较高;光谱反射率通过对数、比值转换,可以有效的提高叶绿素a和浊度估测模型的精度,却对透明度作用不大。总体来说,叶绿素a和浊度估测模型效果较好,透明度高光谱估测模型相对较差,需进一步研究。 相似文献
95.
96.
The Extended Kalman Filter Data Fusion Algorithm Based on Discrete Stationary Wavelet Transformation
It is difficult to establish precise mathematical model in extended Kalman filter data fusion algorithm for GPS/ DR integrated vehicle navigation system, an improved extended Kalman filter data fusion algorithm is put forward based on Discrete stationary wavelet transformation. The simulation results show that the algorithm is better than the extended Kalman filter data fusion algorithm, and is available for GPS/DR integrated vehicle navigation system. 相似文献
97.
An unwelcome side effect of the globalization of the world's economy and dramatic increase in human mobility and trade has been a marked increase in species invasions that have posed severe threats to the ecological, economic, and/or social stability of the introduced regions. In this review, we analyzed the application of molecular markers in invasion genetics of invasive alien insect pests (IAIPs) in China based on a bibliometric survey. Our report discusses the considerable progress that has been made during the past two decades in understanding the invasion genetics of IAIPs in China. We reviewed the major findings in the main topics including the effects of origin and routes of invasion on genetic structure, spatial and temporal genetic changes, factors contributing to the genetic changes of IAIPs, and genetic mechanisms involved in IAIPs' invasions. On the other hand, some of these research areas remain relatively unexplored in China, especially those pertaining to spatial and temporal genetic changes of IAIPs and genetic mechanisms of IAIPs' invasions. Finally, the future research prospects of IAIPs in China are discussed. We hope this review will stimulate an interest in and provide an increased understanding of the field of invasion genetics of IAIPs in China, and provide a basis for future research in this area. 相似文献
98.
【目的】研究小豆矮秆窄叶突变体(nld)的遗传行为及观察矮秆窄叶突变基因控制的农艺性状的变化。【方法】选用高秆小豆种质资源GM904与nld进行杂交,对亲本和F2、F3、F4各世代分离群体中个体形态进行调查统计,对株高、茎粗、主茎节数、第1至5节间长、前10节间长、单株粒数、百粒重、单株产量、荚长、荚宽、单株荚数等15个农艺性状进行调查分析。【结果】遗传分析结果表明,突变体中矮秆窄叶性状由一对隐性单基因控制。各性状间存在一定的显著或极显著差异,其中株高、茎粗、主茎节数、前10节间长、荚长、单株荚数的广义遗传力达到0.9以上,可作为小豆杂交育种的选择指标。【结论】矮秆窄叶突变基因导致株高变矮,叶变窄,茎变细,主茎节数减少,各节间长缩短,荚变小,产量显著降低。 相似文献
99.
100.
Astrid?P.?Vasquez James?L.?Regens James?T.?GunterEmail author 《Journal of Soils and Sediments》2004,4(3):151-156
Background and Goal A number of global events have generated intense scientific scrutiny and public concern of polychlorinated dibenzo-p-dioxins (dioxin). DIoxins have been associated with a range of adverse health effects. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is recognized as among the most dangerous of the dioxin compounds, and was a contaminant found In one of the
herbicides used for vegetation control during the Vietnam conflict: Agent Orange. As a result of purging spray systems and
leaking drums of Agent Orange concentrate, TCDD contamination occurred in the soils surrounding Hardstand 7 at Eglin Air Force
Base, Florida. This research uses a multimedia model to estimate the TCDD concentrations in surface soil around Hardstand
7 for a 70-year time Interval beginning with observed surface soil concentrations 1984.
Methods Hardstand 7 is a nearly 40-m circular concrete and asphalt aircraft parking area. The hardstand was used as a staging area
for spraying equipment used to disseminate herbicide In a test area called C-52A within EAFB. Concentrated herbicide was also
stored in 208-L barrels for use with the equipment, and later, for disposal. In 1984, a field investigation characterized
the extent of TCDD contamination in surface soils around Hardstand 7 using a radial sampling protocol. The 1984 observed concentrations
and locations was used in a multimedia model, CalTOX, as an initial source term concentrations and locations to estimate expected
concentrations during the subsequent 70-years.
Results The results indicate that more than 94% of the TCDD observed in surface soils 1984 will remain after a 70-year period. Access
restrictions and remediation activities at the site eliminate bar verification of the CalTOX estimates. Conclusions. TCDD
is highly persistent in the soil medium and natural attenuation may not produce a significant decrease In soil concentrations.
Recommendation Active remediation actions may be required to prevent exposure to TCDD contamination surface soils. Verifying CalTOX concentration
estimates an Important step that should be performed, however, the, model provides an easy to use tool to estimate TCDD surface
soil contamination at herbicide storage or dispersion staging sites. 相似文献