小麦出苗至抽穗期土壤湿度预报及喷灌量计算

以黑龙江省８５０农场的资料进行分析,５至６月份小麦出苗、拔节至抽穗阶段,经常出现干旱,是需水关键期,对产量影响极大。所以利用麦田土壤湿度资料,建立经验公式,对土壤墒情进行预测预报,从而获得最佳喷灌时间及喷灌量,为节约用水、计划用水提供了可靠依据。     

广武新灌区春小麦土壤水分变化规律研究

通过对广武新灌区春小麦土壤水分的垂直变化、季节变化和时空变化的研究,将广武新灌区０～１００ｃｍ土层划分为活跃层、贮水层、阻隔层和无效水分层,为寻找新灌区节水途径奠定了基础。     

The role of anthropogenic activities in karst spring discharge volatility

The traditional hydrological time series methods tend to focus on the mean of whichever variable is analysed but neglect its time‐varying variance (i.e. assuming the variance remains constant). The variances of hydrological time series vary with time under anthropogenic influence. There is evidence that extensive well drilling and groundwater pumping can intercept groundwater run‐off and consequently induce spring discharge volatility or variance varying with time (i.e. heteroskedasticity). To investigate the time‐varying variance or heteroskedasticity of spring discharge, this paper presents a seasonal autoregressive integrated moving average with general autoregressive conditional heteroskedasticity (SARIMA‐GARCH) model, whose the SARIMA model is used to estimate the mean of hydrological time series, and the GARCH model estimates its time‐varying variance. The SARIMA‐GARCH model was then applied to the Xin'an Springs Basin, China, where extensive groundwater development has occurred since 1978 (e.g. the average annual groundwater pumping rates were less than 0.20 m³/s in the 1970s, reached 1.20 m³/s at the end of the 1980s, surpassed 2.0 m³/s in the 1990s and exceeded 3.0 m³/s by 2007). To identify whether human activities or natural stressors caused the heteroskedasticity of Xin'an Springs discharge, we segmented the spring discharge sequence into two periods: a predevelopment stage (i.e. 1956–1977) and a developed stage (i.e. 1978–2012), and set up the SARIMA‐GARCH model for the two stages, respectively. By comparing the models, we detected the role of human activities in spring discharge volatility. The results showed that human activities caused the heteroskedasticity of the Xin'an Spring discharge. The predicted Xin'an Springs discharge by the SARIMA‐GARCH model showed that the mean monthly spring discharge is predicted to continue to decline to 0.93 m³/s in 2013, 0.67 m³/s in 2014 and 0.73 m³/s in 2015. Copyright © 2014 John Wiley & Sons, Ltd.     

Macroalgae in a spring stream in Shanxi Province： composition and relation to physical and chemical variables

Fourteen stream segments were investigated throughout the Xin’an Spring in Shanxi Province, China in 2004. The variation ranges in stream size, current velocity, discharge, dissolved oxygen, and specific conductance were large. Twenty-two macroalgae species were found in the stream. Major divisions in terms of species numbers were Chlorophyta (59.1%), Cyanophyta (22.8%), Xanthophyta (9.1%), Rhodophyta (4.5%) and Charophyta (4.5%). The most widespread species, Cladophora rivularis (50.0%), also Oedogonium sp. (42.9%) and Spirogyra sp. (42.9%) were well represented throughout the stream, whereas another 10 species were found in only one sampling site. Total percentage cover varied from <1% to 90%. Red algae Batrachospermum acuatum and the charophytes Chara vulgaris have the highest percentage cover. Among the parameters analyzed, the stream width, specific conductance and dissolved oxygen were the ones that more closely related to the species number and percentage cover of macroalgal communities. The species number of each site was negatively correlated with dissolved oxygen content. The total percentage cover of the macroalgae was negatively correlated with the stream width and the specific conductance.     

春季水华对南黄海总溶解态无机砷生物地球化学行为的影响

利用氢化物发生-原子荧光光谱法(HG-AFS)对2007年3月30日至4月23日南黄海海域总溶解态无机砷(TDIAs,[TDIAs]=[As5+]+[As3+])的含量进行了测定,其中针对水华中心区域(BM1站)进行了25h的连续观测,以探讨春季水华对有毒类金属元素砷的生物地球化学行为的影响。结果表明,TDIAs的浓度范围为7.9~22.3nmol/L,平均值为(17.8±1.9)nmol/L。TDIAs在南黄海的分布主要表现为由近岸向外海逐渐升高的趋势,最大值出现在南部海域底层海水中。近岸海域表、底层TDIAs的含量相当,而中、南部海域由于存在明显的密度跃层,表、底层TDIAs的浓度具有显著性差异。2007年3月31日至4月1日研究区域西南部受到沙尘天气和降雨的影响,表层海水中TDIAs的含量显著升高。研究区域中、南部海域在观测期间暴发了典型的黄海春季水华,通过大面观测和对重点区域的连续观测可以发现,水华期间TDIAs的分布和磷酸盐类似,与Chl a呈现出较好的负相关关系(r=0.51,P0.05,n=39)。经初步计算,浮游植物水华对10m以上表层水体中TDIAs的清除量约为2.4nmol/L,占表层保有量的15%左右。通过箱式模型计算得出黄海TDIAs的停留时间约为(18.2±8.5)a,远远低于大洋。通过对该海域砷、磷摩尔比值的计算可以发现,南黄海砷、磷摩尔比值约为大洋中的20倍左右,这可能会引起浮游生物对砷酸盐的大量吸收和转化,从而带来潜在的生态危机,需要引起足够的重视。     

利用不同方法反演冬小麦叶面积指数研究

基于高光谱数据的叶面积指数监测是快速获取冬小麦叶面积指数的重要方法。为了探究回归方法和高光谱数据变换对冬小麦叶面积指数反演精度的影响,采用逐步回归和偏最小二乘回归方法,分别建立基于冬小麦拔节期冠层高光谱数据、一阶导数光谱数据、二阶导数光谱数据和对数光谱数据的叶面积指数多元线性回归模型。结果显示,导数和对数变换能够提高冬小麦LAI反演精度,以蓝紫光、绿光、红光和近红外波段建立的一阶导数光谱数据逐步回归模型最优,建立回归模型的决定系数R2为0.974,交叉验证的RMSE为0.131,可为冬小麦LAI估算的方法选择和数据处理提供依据和参考。     

甘肃省黑河干流中游地区泉水动态特征及预报

在简述区域水文地质条件的基础上,依据1986～2007年泉水流量系列观测资料,详细论述了区内下降泉、上升泉的年内和多年动态变化特征,对比分析了1967年、1984年、2006年测区各泉域泉水量和泉水总量的时空分布规律和变化特征。利用已有的潜水二维流水量数学模型,推递并建立了利用泉点周围节点水头(水位)预报泉水流量的数学模型,并对测区泉水总量未来15年的变化趋势进行了预报。结果表明,在现状节水灌溉条件下,由于出山径流量的增加和地下水开采量的减少,未来黑河干流中游地区的泉水资源基本处于稳定状态。     

黑龙江四平山金矿深部矿体预测

四平山热泉型金矿床成矿的地质条件和产出的大地构造背景优越,具有非常好的浅成低温热液矿床的成矿环境,其深部存在新矿体的可能性较大。本文对照该类矿床的成矿模式,结合区域地质特征及钻探和物探工程的揭露情况对矿区深部可能存在的矿体位置进行了预测,结果表明矿区148线ZK927孔和ZK914孔之间,有断层通过的电、磁异常套合部位,深度300～500m处可能有新矿体存在。     

中国温泉之乡巢湖市的地热资源及其开发利用

巢湖市内汤池、半汤、香泉、昭关等四大温泉,水温42—63℃,日出水量达1万m~3,储量丰富,水质优良。近年来,不断提升巢湖市温泉资源的开发利用和保护水平,温泉度假旅游已成为巢湖旅游业的拳头产品。2009年12月,经国土资源部和中国矿业联合会专家评审,巢湖市被命名为中国温泉之乡。