水土保持专家系统的探索与试验

本文介绍了黄土地区水土保护专家系统的建筑原理与方法，系统采用压缩编码方式存贮各种地学图形与遥感图象数据，具有数据与图象的存贮更新，查询检索，分析处理，图象显示和自动制图功能，该系统可对黄土地区的土壤侵蚀进行快速，准确的预测，预报，并对水土流失的综合治理，水土保护规划提出几种可行性建议供用户选择，用该系统对山西省离石县王家沟流域羊道沟的土壤侵蚀进行了试验研究，并对试验结果进行了系统评价。     

乙草胺在水中的光化学降解

以高压汞灯、氙灯、自然光为光源 ,研究了乙草胺在不同类型水中的光解动态。结果表明 :乙草胺的光量子产率低 ;高压汞灯光照下 ,乙草胺在水中的光解速度为纯水 >河水 >塘水 >稻田水 ,其光解率与水介质的 pH呈正相关 ;不同光源照射下 ,乙草胺于纯水中的光解速率有显著的差异 ,表现为高压汞灯 >氙灯 >自然光 ,同时其光解产物也存在明显的不同。     

三工河流域水量转换特征及水资源利用

三工河流域从源头至尾流经了不同的地质单元,在河流的不同地段上,水资源表现形式各不相同,或由地下水补给地表水,或由地表水给地下水。本文分析了不同地段上的水量转化特征,并在此基础上探讨了该区水资源利用现状,存在的问题,提出了有效的对策。     

岳普湖县水资源开发利用状况及发展方向

本文据野外实地考察和有关资料，论述岳普湖县水资源开发利用现状及存在的问题，探讨了水利发展方向及对策。     

Detection of race 1 strains of <Emphasis Type="Italic">Ralstonia solanacearum</Emphasis> in field samples in Taiwan using a BIO-PCR method

Bacterial wilt caused by race 1 strains of Ralstonia solanacearum is endemic on tomato produced in diverse agro-ecosystems in Taiwan. Using a new BIO-PCR protocol developed in this study, R. solanacearum was detected in soil, weed, and water samples collected from eight fields with different disease histories and cropping systems located in major tomato production areas. The sensitivity of the BIO-PCR was 1.9 CFU ml⁻¹ and 17 CFU g⁻¹ of soil for pure suspension and infested soil, respectively. The positive detection frequency of the BIO-PCR method was 66.6, 39.6, 23.1, and 31.8% for all tested samples of soil, weed rhizosphere soil, weed root, and water, respectively, and was higher than plating on MSM-1 medium. Detection of R. solanacearum from field soil indicated that spatial distribution of the pathogen in the field was not even regardless of the presence or absence of the disease and the different agro-ecosystems where the sampled fields were located, and the degree of unevenness was higher when tomato was absent from the field. Weed rhizosphere soils could be good sampling targets to monitor the pathogen in the field, because a higher positive detection proportion and population of R. solanacearum were found in the rhizosphere rather than the root of the collected weed samples. Symptomless weeds and contaminated irrigation, standing, or drainage waters were found to be important for the over-season survival and dissemination of R. solanacearum.     

干旱区潜水蒸发埋深及土质关系实验分析

潜水蒸发量是水资源分析评价中推算陆面总蒸发量的重要因素之一，尤其在缺乏资料地区更为重要。本文根据阜北农场地下水科研站多年积累的资料，在前人研究潜水蒸发的基础上，说明本地区潜水蒸发埋深与不同土质的关系及潜水蒸发量年内之间的变化规律。     

榆林市水资源可持续开发和利用研究

对榆林市水资源的基本特征和开发利用现状进行系统分析,通过科学合理的预测,提出了榆林市水资源可持续开发和利用的主要思路和途径。     

和田河流域水文特征及区域水资源评价

1.和田河流域自然地理概况和田河流域地处我国新疆塔里木盆地中西部,东经77°40′-81°40′,北纬35°00′-40°30′。和田河水系发源于昆仑山北坡,是塔里木河水系中仅次于叶尔羌河和阿克苏河的第三大河。其上游有两源;东源玉龙喀什河;西源喀拉喀什河。两河在阔什拉什会合后,横穿塔克拉玛干沙漠腹地,在阿瓦提县肖夹克之西与叶尔羌河、阿克苏河相汇构成塔里木河,形成     

Subsurface Drainage for Rehabilitation of Waterlogged Saline Lands: Example of a Soil in Semiarid Climate

In irrigated agriculture of arid and semiarid regions, soil salinity, coupled with waterlogging, is a serious problem. Provision of subsurface drainage seems to be a prerequisite for optimal crop production. A study was conducted to evaluate the long term (8-year) impact of a subsurface drainage system on soil properties and yields of wheat. The study was located in a severely affected, waterlogged, barren, sandy loamsaline soil (Comborthids). The subsurface drainage system was installed at a 1.75 m depth with three drain spacings (25, 50, and 75 m). The drains facilitated reclamation of the waterlogged saline land which had variations in salt removal with space and time. The removal of salts from the root zone varied initially with distance from the drain and with depth. However, after a few years, the variations were reduced and the land was reclaimed sufficiently to grow most of the crops of the region. Plots provided with a drain spacing of 75 m required more time for complete reclamation compared to plots provided with 25 m drain spacing. Leaching through subsurface drainage increased soil porosity, modulus of rupture, infiltration rate, organic carbon, available nitrogen, phosphorus, potassium, and available water, and decreased bulk density differently in the three drain spacings (20, 50, and 75 m). In the 75 m drain spacing plots, soil salinity (EC e ) and water content remained higher than in the 25 and 50 m drain spacing plots. Soil EC e and water content were less near the drains, were highest in areas midway between the drains, and the effects were more apparent in the summer season. Wheat grain yield decreased with increasing drain spacings in the initial years of reclamation. With the gradual improvement in soil salinity, yields from plots with a 75 m spacing reached those of the narrower drain spacing plots by the fourth year. It was concluded that by installing a subsurface drainage system in a monsoon climate, waterlogged saline soils can be reclaimed by the natural leaching that can take place from rainfall. The optimum yield can be attained with a drain spacing of 75 m, which is 50% more than the design spacing of 50 m. Faster reclamation and more yield were obtained with a 25 m drain spacing and was achieved at a higher cost for the more expensive drainage system.     

秦王川灌区水资源可持续利用潜力分析

水资源是秦王川灌区发展的重要支撑 ,水资源能够保证未来的可持续利用 ,可为整个秦王川灌区实现可持续发展的基本目标创造良好的条件、打下坚实的基础。本文基于对水资源四种变化率指标的计算 ,评判了未来较长一段时间内秦王川灌区水资源可持续利用的潜力大小 ,即 2 0 1 0年灌区主要供给水资源能否满足各方面的用水需求 ,从而为该区域水资源利用宏观决策提供依据     

渭干河灌区水盐动态变化及其耦合分析

渭干河是新疆著名大河之一,是渭干河绿洲的塑造者,该绿洲的生存和发展与灌区水资源利用关系密切。渭干河灌区环境恶化主要是在自然及人为因素共同作用下形成的。灌区分布于独立而封闭的冲积扇上,原生土壤普遍含盐,加之长期以来重灌轻排,土壤次生盐渍化严重。本文根据渭干河灌区多年水盐监测资料,探讨灌区多年来的水盐动态变化及其耦合关系。研究表明:灌区盐分来源主要为引水携盐,灌区排水是灌区盐分去处的主要途径;灌区地下水埋深,地下水水质存在时间和空间上的变化,地下水状况决定水化学类型。     

论干旱区绿洲的可持续发展与水资源的关系--以河西走廊绿洲为例

文章以地处干旱区内陆的河西走廊绿洲为例 ,阐述了绿洲的形成与发育分布特征 ;较为系统的分析了绿洲现状存在的主要问题 ;研究了河西走廊水资源及利用现状 ,提出了绿洲水资源开发利用的三个阶段 ;探讨了节水的必要性与绿洲水资源开发利用关系。     

新疆水土保持土壤侵蚀信息系统研究

新疆水土保持土壤侵蚀信息系统（ＳＥＩＳ）是新疆水土保持建设规划的一个子课题。是利用计算机及地理信息系统技术、数据库技术及地学编码研究设计新疆土壤侵蚀信息系统,用于分析研究新疆的水土流失状况及治理方法。     

荒漠草地植物稳定性氮同位素对水分变化的响应

水分是影响荒漠地区植被分布的重要因素,近年来,我国西部地区的气候正向暖湿化发展,降水的变化势必会对植物N同位素的吸收、分配产生影响。利用¹⁵N标记法,通过不同的增水处理,研究古尔班通古特沙漠南缘标记样地和未标记样地植物N同位素吸收和分配对水分变化的响应,得出以下结论：① 增水处理增加了对土壤水分的补给,显著提高了土壤水分含量;② 未标记样地植物稳定性N同位素的[WTBX]Ndff[WTBZ]值的变化范围为0.39～0.59,其最大值出现在30%增水处理,最小值出现在20%增水处理;③ 氮素标记后,样地植物稳定性N同位素Ndff值明显上升,其变化范围为15.27～31.24。从植物不同部位来看,植物吸收的氮素在植物茎中的分配比例最大,而在根中的分配比例最小。     

奎屯,乌苏,独山子地区水资源污染现状

通过对本区水质监测资料,废水排放资料的分析,评价区域水资源污染情况,找出目前主要的水环境问题,提出解决区水环境问题的途径或措施。     

林业除草剂咪唑烟酸在土壤、水及杂草植株中的残留检测

采用HPLC建立了一种林业常用除草剂咪唑烟酸在土壤、水及杂草植株中的残留检测方法。土壤及杂草植株样品用甲醇+0.1mol/L的NH4HCO3水溶液(体积比70∶30)提取,水溶液样品直接用二氯甲烷萃取。 添加法测定结果表明:当添加水平为0.1~5 mg/kg时,平均回收率为86.9%~103.5% 。在土壤及杂草植株中的最小检知浓度分别为0.05、0.1 mg/kg;水中最小检知浓度为0.01 mg/L。     

黄土区小流域水沙对降雨及土地利用变化响应研究

降雨和土地利用/覆被变化是流域径流、泥沙的两个主要影响因子。本研究采用SWAT模型,用固定其中一个影响因子而改变另一个影响因子的方法,对研究区降雨变化与土地利用/覆被变化对径流泥沙影响进行估算,目的在于从年月不同时间尺度上确定黄土高原小流域水沙对降雨和土地利用变化的响应状况。结果表明,在年尺度上降雨变化对径流影响的贡献率为84.20%,土地利用变化对径流影响的贡献率为28.63%;在月尺度上,降雨对径流贡献率也大于土地利用对径流的贡献率,尤其在雨季降雨对径流的影响程度和土地利用对径流影响程度的比值最大可以达到4.5。因此,不论在年尺度还是月尺度上,降雨对径流的贡献率都远远大于土地利用对径流的贡献率。此外,研究结果也表明流域年降水量和流域森林植被盖度均与流域径流模数或输沙模数呈指数关系。     

绿洲水土资源协调开发的SD模型：以哈密为例

本文以节水措施的实施、供需水系统的完善和农业结构的调整为前提,通过对哈密市水资源系统、供需各要素的相互关系及其所隐含的反馈信息的考察,建立了哈密市水土资源协调开发的SD模型。通过模型求解,得出了哈密市在一定水资源利用状况下的土地开发规模,并确立了与之相适应的耗水结构及作物种植结构。     

稻田除草剂水体残留对水生植物大薸的影响

采用模拟方法研究了稻田3种常用除草剂丁草胺、苄嘧磺隆、2甲4氯钠残留水体对大薸生长的影响。结果显示:(1)3种除草剂水体残留对大薸植株形态影响以苄嘧磺隆处理最为明显,残留浓度大于0.01 mg/L可导致大薸植株大量死亡。4.25 mg/L的丁草胺和3.36 mg/L的2甲4氯钠残留对大薸的生长均有一定的抑制作用,但短期内不能致死。当水体除草剂残留降低至田间常规管理施用浓度的1/8时,即丁草胺0.53 mg/L、苄嘧磺隆0.01 mg/L、2甲4氯钠0.42 mg/L,大薸植株形态的药害影响已经明显减轻。(2)苄嘧磺隆水体残留大于0.01 mg/L时大薸干物质产量显著降低,分株生长受到严重抑制。丁草胺残留浓度为0.53 mg/L时促进大薸干物质积累和分株生长,当残留浓度大于1.06 mg/L时大薸干物质积累和分株生长受到抑制。2甲4氯钠残留浓度低于3.36 mg/L对大薸的干物质产量、分株数及植株含水率影响一般。     

Target-site basis for resistance to acetolactate synthase inhibitor in Water chickweed (Myosoton aquaticum L.)

Water chickweed is a widespread and competitive winter annual or biennial weed of wheat in China. One Water chickweed population (HN02) resistant to several acetolactate synthase (ALS) inhibitors was found in Henan province of China. Whole-plant bioassays showed that HN02 was high resistance to tribenuron (292.05-flod). In vitro ALS assays revealed that resistance was due to reduced sensitivity of the ALS enzyme to tribenuron. The I₅₀ value for HN02 was 85.53 times greater respectively than that of susceptible population (SD05). This altered ALS sensitivity in the resistant population was due to a mutation in the ALS gene resulting in a Pro197 to Ser substitution. Cross-resistance experiments indicated that HN02 exhibited various resistance patterns to pyrithiobac-sodium, florasulam and pyroxsulam, without resistance to imazethapyr. This is the first report of tribenuron-resistant Water chickweed in Henan province of China, target-site based resistance was established as being due to an insensitive form of ALS, resulting from a Pro to Ser substitution at amino acid position 197 in the ALS gene.