美国冬小麦产量遥感预测方法

介绍了依据时序遥感植被指数数据进行产量预测的方法。通过美国冬小麦产量的历史趋势分析去除趋势产量 ,得到气象产量。利用区域作物生长过程线 ,提取曲线的各个特征参数 ,并将各参数与气象产量的值进行相关分析 ,得到美国冬小麦产量遥感敏感因子 ,采用一次线性拟合的方法建立回归方程 ,估算当年的冬小麦产量。依据此方法对美国 2 0 0 3年各州的冬小麦单产进行了预测 ,并将最终的预测结果与美国农业统计局的数据进行了对比 ,两者间的误差在 - 11 4 2 %至 11 10 %之间 ,相关系数为 0 89。     

成都地区居民疾病死亡率与元素背景关系初探

通过对成都市居民高死亡率的疾病类型和生命元素关系的探讨,并将其结果与成都市深、浅层土样相应元素背景值对比。结果表明:居民高死亡率的疾病与浅层土样中的有毒及过量有毒必需元素的含量成正相关,而与深层土样的生命元素偏低有关。     

保水剂在作物抗旱栽培中的应用

应用小麦、花生的田间小区试验资料，分析了保水剂在抗旱栽培中的作用，结果表明：保水剂是一种十分有效的抗旱剂，确定起到保墒增湿的作用，而且价格低廉，技术容易掌握，是一种经济有效、增产节能的栽培措施，可推广使用。     

水分影响作物发育进程的研究

不分是影响作和发育进程的重要因子，作者在田间试验的基础上，研究了不同阶段干旱处理对作物发育进程的影响，这对于指导田间灌溉，节约水资源，调节作物发育进程，提高作物产量及品质有重要意义。     

大面积农作物苗情长势的气象卫星遥感统计方法研究

农作物苗情长势是指导农业生产、预测农作物产量的重要参考，本文研究利用气象卫星绿度值资料统计农作物三类苗情的技术方法。首先根据１９８６—１９９４年地面苗情观测资料分析了淮北平原小麦苗情的统计特征，提出４条假设，以此４条假设作为苗情统计方程的边界条件，并结合其它订正条件对绿度值进行聚类分析，获得各地作物苗情的判别标准，从而获得农作物苗情长势遥感分布图     

The Impact of Erosion on Soil Productivity—An Experimental Design Applied in São Paulo State, Brazil

Soil erosion is the principal threat to agricultural sustainability, affecting both the characteristics of the in situ soil and its productive potential. However, soils vary in their resilience and there are very few empirical data upon which to appreciate the degree and type of impact on the soil caused by erosion. This paper describes an experiment designed to generate such data based on soil loss and runoff plots, and it reports on nearly nine years of experience with the design at the Instituto Agronômico, Campinas, Brazil on a Latosol (Oxisol). After seven years of erosion induced by four levels of artificial cover, the effective rainfall on the most eroded soil was 20 percent less than on the control full cover. Crop yields were also found to be significantly affected: in 1995 by nearly 700 kg/ha and in 1996 by over 1000 kg/ha—a 50% decline in yield, amounting to a loss of 4 kg/ha of maize per tonne of cumulative soil loss. Losses of nutrients (organic C, P, K, Ca and Mg) in the runoff and eroded soil were also significant with far higher levels of loss associated with the eroded sediment. Changes in the in situ soil were less clear, but a test of trends showed that the decreases in organic matter and increases in acidity could unambiguously be attributed to soil erosion. Average enrichment ratios of the eroded sediment were 1.3 for organic C, 2.6 for P, 0.7 for K, 1.3 for Ca and 1.2 for Mg. Erosion has also affected the maize quality—mainly N, Ca and B nutrient content. Through these various measures, we conclude that seven years of induced erosion has had a marked effect on soil productivity, and for the first time we are now in a position to begin calculating the financial impact of the erosion process on future yields and farmer livelihoods.     

塔里木河上游地区土壤水盐变化与作物的关系

本文利用塔里木河上游灌区阿克苏水平衡站的有关试验观测资料，对绿洲农田地下水，土壤中水和盐的运动及植物耐盐性进行了对比分析，总结了土壤水盐运动的某些规律。．     

农业地质的研究现状及发展动向

文章讨论了农业地质的基本概念,提出了农业地质是研究制约大农业的地质背景条件和拓宽地质服务领域的地学与农学之间的交叉学科,对其研究现状和有关成果作了介绍,在此基础上对农业地质的发展动向和存在问题进行了分析。     

气候变化对作物产量影响的动态统计评价模式

气候变化对作物产量影响的动态统计评价模式，主要是运用积分回归原理，探索作物生育期内以旬为时间单位的气候变化对作物产量形成的影响规律。由于该模式能及时连续地进行气候影响评价，使评价工作能直接的为农业生产进行跟踪服务。在建模过程中引用了三项式产量预报模型、特殊影响因子诊断分析和选取最佳积分因归方程等方法，并在试用中取得了较满意的结果。     

陕西潼关金矿区农田土壤Hg污染的环境效应

以潼关金矿区农田土壤Hg污染区的小麦、蔬菜、水果中的Hg含量为重点研究对象,与尚未污染的农田土壤区进行对比,研究土壤Hg污染的农作物效应.评价区小麦样本Hg的超标率为78.57%,小麦Hg超标与土壤Hg污染的关系明显.评价区萝卜样本超标率为40%,叶菜、西红柿、苹果、红薯中样本超标率均为100%,对照区果蔬类也全部超标,但明显低于评价区.评价区农作物Hg超标倍数从大到小依次为:青菜＞油麦菜＞萝卜叶＞西红柿＞苹果＞红薯＞小麦＞萝卜.土壤Hg污染的环境效应极为严重,矿区环境污染防治刻不容缓.