古尔班通古特沙漠植物雾凇凝结特征

古尔班通古特沙漠冬季稳定积雪期长,多雾凇天气.通过2007年11月~2008年3月在沙漠南缘的定位实验观测,发现植物雾凇凝结水总量平均为5.8 mm,占冬季降水量的21.8%,其中,沙漠区垄间和垄上植物雾凇凝结水总量分别是3.8 mm和9.1 mm,各占冬季降水量的14.4%和34.3%;植物雾凇凝结水量是雪面凝结水量的5倍;荒漠植物的雾凇凝结水可以增加古尔班通古特沙漠冬季植被分布区域水资源量.雾凇形成的最大风速一般小于3m/s;-15℃~-20℃是雾凇形成次数最多的气温区间,占全部雾凇日数的24.3%,气温低于-30℃时雾凇凝结量显著减少;观测期雾凇形成时大气最大相对湿度小于80%的日数占冬季雾凇日数的41%.低温、高湿、低风速的气象条件,加之梭梭枝条的细直径和针状叶特征,是古尔班通古特沙漠冬季具有丰富植物雾凇凝结水的重要原因.     

某灌区地下水变化规律研究

以新疆某灌区为研究对象分析地下水位变化,研究结果表明,渠道渗漏和深层渗漏分别占地下水年补给量的48%和44%。通过蒸发和植物根系吸收的地下水排放量占年度地下水总排放量的82%。经过对建立的模型校准和验证后,模型可被用于评估渠道和农场灌溉节水等方式对地下水和灌溉水造成的影响。     

覆盖与衬垫对沙地土壤水分影响的初步研究

通过对陕北毛乌素沙地不同农业措施土壤水分的观测分析,揭示出沙区土壤水分受补(灌)水量与农业措施如地下衬垫与地表覆盖的双重影响与控制,地下衬膜和地表覆膜抑渗、抑蒸保墒效应促进了土壤--作物--大气连续体系中水分有效循环,增加了耕层土壤贮水量,加大植物可利用的土层水分,从而使苜蓿增产,并可节水32%～40%,为沙区推广地下衬垫(膜)与地表覆盖(膜)节水技术提供科学依据.     

节水点滴

1)洗少量衣物不用洗衣机凑足一定量后再用;2)洗餐具不要让自来水常流;3)关紧龙头不使滴水,4)刷牙洗脸时不使龙头水常流;5)清除地面尘垢时,以扫代冲;9)汽车保洁先水刷,后水冲;7)绿化浇水宜选在日气温最低时;8)选种节水植物。     

氢化物发生-原子荧光光谱法测定植物样品中汞硒砷

植物样品经硝酸-高氯酸一次湿法消解后,用氢化物发生-原子荧光光谱法同时测定汞、硒、砷。测定时加入消泡剂磷酸三丁酯,可有效消除泡沫,降低记忆效应,提高精密度。方法精密度(RSD,n=12)为汞2.96%,硒0.96%,砷2.49%。经加标回收试验和国家一级标准物质验证,测定结果与标准值吻合。     

半透膜滴灌对节水灌溉技术的影响研究

半透膜滴灌是一种符合现代农业要求的滴灌手段,传统灌溉技术节水能力较差,导致大量水资源浪费,对农作物的生长速度和生长状态造成不良影响。为了检测半透膜滴灌对节水灌溉技术的影响,设计了对比实验。通过建立实验参数,选取喷灌方法、普通滴灌和半透膜滴灌三种方法进行了对比试验,分析三种方法的水资源使用率和植物生长状态,并进行对比。实验结果表明:半透膜滴灌能够最大程度的利用水资源,防止资源浪费,促进植物以最好的状态生长。降低农药使用量和农民的劳动量,以期为节水农业发展提供技术保障。     

辽宁某萤石矿捕收剂效果对比试验

以辽宁某萤石矿为研究对象,通过纯矿物、实际矿物浮选试验以及接触角测试、红外光谱分析对比2种不同植物油酸对萤石的浮选效果。纯矿物试验结果显示,植物油酸b对萤石的捕收性及选择性优于植物油酸a;接触角测试结果显示,植物油酸a与b作用于萤石纯矿物后接触角均由亲水角转变为疏水角,当植物油酸b用量为50mg/L时接触角为最大的112.7°,此时萤石可浮性最好。红外光谱测试结果显示植物油酸b能够在萤石表面发生较强的化学吸附。最终选择植物油酸b进行实际矿物浮选试验,拟定粗选磨矿细度为-0.074mm粒级含量占71.60%,粗选抑制剂为水玻璃,精选抑制剂为六偏磷酸钠,再磨细度为-0.043mm粒级含量占56.70%,进行一粗一扫六精,中矿顺序返回工艺流程。最终可获得CaF₂品位为97.89%回收率为79.61%的萤石精矿。     

中国西部、东北地区湖泊沉积物中碳酸盐碳、氧和有机碳同位素组成及与环境的响应

湖泊沉积物中碳酸盐碳、氧和有机质碳同位素组成受湖泊环境介质的控制,可以有效地指示环境演化过程。通过对中国东北和西部青藏高原、新疆现代湖泊表层沉积物的碳酸盐的碳、氧同位素组成(δ13C、δ18O)、有机碳同位素组成(δ13Corg),以及有机质含量(TOC)、C/N分析研究,发现当湖泊中以浮游植物来源有机母质为主时,其δ13Corg为-30‰~-23‰;以硅藻为主的藻类来源时,δ13Corg为-30‰~-16‰;以挺水植物来源,δ13Corg为-30‰~-24‰;沉水植物来源,δ13Corg为-24‰~-16‰;以水生植物和陆生植物来源为主时,δ13Corg为-30‰~-20‰;当以陆生植物来源为主时,其δ13Corg为-26‰~-24‰。当西北地区半封闭湖泊表层沉积物中碳酸盐含量大于30%时,湖泊表现出δ13C、δ18O之间较好的正相关性,TOC主要以内源有机质来源为主。     

磷处理粉煤灰可作农业土壤磷源

粉煤灰(简称CCP或ash)具有改良土壤,增加植物产量的功能。此外,由于它特殊的多孔结构,也可用作吸纳并承载植物养分的载体。用NaH2PO4配制成含磷0.10mol/L浓度的溶液,对采自加拿大西安大略省Sarnia地区Lambton电厂的底灰(bottomash)进行振荡浸渍处理。结果表明,振荡浸渍66h后的粉煤灰中磷含量可达784×10-6。以磷处理粉煤灰、未进行磷处理的粉煤灰和石英砂按比例混合,作为基本生长介质进行玉米种植实验,其中实验配方设计为生长介质中含磷量分别为标准含磷浓度(50×10-6)的10%、25%、50%、75%和100%。生长26、34和46d后分别与不含磷的空白配方、施加含氮-磷-钾为0-20-0标准磷肥并控制磷含量为标准浓度(50×10-6)配方进行生物产量对比。生长实验结果表明,以磷处理粉煤灰供磷的生长介质,当含磷量为标准浓度的25%至100%时,其植物生长量就比添加标准浓度磷肥的配方好。种植46d后的生物生长量统计结果显示,含磷分别为标准浓度50%、75%和100%的实验介质中,玉米杆的鲜重较施标准磷肥介质中玉米分别增长39.46%、42.73%和46.13%;玉米杆干重依次增加29.71%、13.39%和28.87%;根鲜重平均增加16.62%;根干重平均增加14.03%。上述实验结果启示,粉煤灰可以很好地吸纳承载磷养分,并持续供给植物吸收生长,如果采用吸纳磷(或其他养分)的粉煤灰改良砂质土壤将有重要意义。     

原子荧光光度法测定植物样品中的铋

植物样品经硝酸-高氯酸1次湿法消解后,用氢化物发生-原子荧光光谱法测定铋。测定时加入消泡剂磷酸三丁酯,可有效消除泡沫,降低记忆效应,提高精密度。方法精密度(RSD=12)铋1.50%。经加标回收试验和国家一级标准物质验证,测定结果与标准值吻合。     

Groundwater recharge in irrigated semi-arid areas: quantitative hydrological modelling and sensitivity analysis

For semi-arid regions, methods of assessing aquifer recharge usually consider the potential evapotranspiration. Actual evapotranspiration rates can be below potential rates for long periods of time, even in irrigated systems. Accurate estimations of aquifer recharge in semi-arid areas under irrigated agriculture are essential for sustainable water-resources management. A method to estimate aquifer recharge from irrigated farmland has been tested. The water-balance-modelling approach was based on VisualBALAN v. 2.0, a computer code that simulates water balance in the soil, vadose zone and aquifer. The study was carried out in the Campo de Cartagena (SE Spain) in the period 1999–2008 for three different groups of crops: annual row crops (lettuce and melon), perennial vegetables (artichoke) and fruit trees (citrus). Computed mean-annual-recharge values (from irrigation+precipitation) during the study period were 397 mm for annual row crops, 201 mm for perennial vegetables and 194 mm for fruit trees: 31.4, 20.7 and 20.5% of the total applied water, respectively. The effects of rainfall events on the final recharge were clearly observed, due to the continuously high water content in soil which facilitated the infiltration process. A sensitivity analysis to assess the reliability and uncertainty of recharge estimations was carried out.     

Assessment of heavy metal accumulation in macrophyte, agricultural soil, and crop plants adjacent to discharge zone of sponge iron factory

The present study deals with the characterization of effluent released from sponge iron industries and distribution of heavy metals in soil and macrophytes near to effluent discharge channel. Apart from this, accumulation of heavy metals in nearby soil and vegetation system irrigated with effluent-contaminated water is also the subject of this study. Physico-chemical analysis of effluent reveals that the concentration of total suspended solids (TSS), total hardness (TH), iron (Fe²⁺), and oil and grease are greater than the IS (1981) norms for discharge of water into inland water body. The soil along the sides of the effluent channel also shows higher concentration of heavy metals than the background soil. The enrichment of the heavy metals are in the order of Chromium (Cr) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Copper (Cu) > Cadmium (Cd). Macrophytes growing along the sides of the effluent channel also show significant accumulation of heavy metals almost in the same order as accumulated in soil. Higher uptake of heavy metals by these varieties reveals that these species can be used for future phytoremediation. The effluent as well as contaminated water is extensively used for irrigation for growing vegetables like tomato (Lycopersicon esculatum) in the surrounding areas. Heavy metal accumulation in this agricultural soil are in the sequence of Cr > Fe > Mn > Zn > Cu > Cd. More or less similar type of accumulation pattern are also found in tomato plants except Fe and Zn exceeding Cr and Mn. Transfer Factor of heavy metals from soil to tomato plants (TF_S) shows average value of <1, suggesting less uptake of heavy metals from soil. Among the plant parts studied, fruit shows least accumulation. Although tomato plants show some phenotypic changes, the survival of tomato plants as well as least accumulation of metals in fruit reveals their tolerance to heavy metals. Therefore it may be suggested that this plant can be grown successfully in the heavy metal contaminated soil. Further research work on in situ toxicity test will be necessary in order to identify the most resistive variety on this particular type of contaminated site.     

RETRACTED ARTICLE: Physiological comparative study of six wild grapevine (<Emphasis Type="Italic">Vitis sylvestris</Emphasis>) accession responses to salinity

Salinity problems for vineyards are in concerns, especially in coastal areas where several aquifers are reported to be affected by seawater intrusion and agricultural contamination. Saline irrigation affects growth, yield, and fruit quality of grapevines. Exploring germplasm base through wild ancestors of the target species is a novel adopted strategy to increase crop tolerance to irrigation with saline water. The effects of salt on growth, organic and inorganic solute accumulations, and chlorophyll florescence were studied on 3-month-old plants of six Tunisian wild grapevines with the objective to identify salt tolerance mechanisms and select tolerant genotypes. Potted plants were grown under controlled conditions and irrigated for 14 days with 0, 100, and 150 mM NaCl nutrient solution. Parameters analyzed were related to growth, water relations, mineral nutrition, and chlorophyll fluorescence. Several processes are operating either at the whole plant or at cell level. They appear to be involved in salt tolerance of wild grapevines and are more efficient in tolerant accessions. Salt adversely affects plant growth and plant nutrition. Reductions of shoot growth rate (relative growth rate, day^?1) reached 49% of control since 100 mM NaCl. They were assigned to stomatal closure and alteration of potassium nutrition and photochemistry. There were significant differences (P < 0.05) within accessions, Tebaba was the most tolerant and Houamdia the most sensitive, while the others were intermediate.     

平原井灌区地下水位监测站代表性分析

平原井灌区可划分为两类区块:村镇驻地区块和农田区块,两类区块地下水位动态特征存在明显差异.通常村镇驻地区块地下水位高于农田区块,形成地下水丘;村镇驻地区块地下水位年变幅小于农田区块;村镇驻地区块地下水位变化相对平缓,而农田区块地下水位常有陡坎,呈阶梯状.根据不同类型区块地下水位动态特点,提出了平原井灌区地下水位监测站点代表性的差异,和选取监测站点的方法.     

白城市水稻种植区灌溉用水的地球化学特征与水稻产量

本文对白城市水稻种植区灌溉用水的物理和化学特征进行了系统研究。结果表明：白城市水稻种植区的灌溉用水水源可以分为地表自流灌溉水、浅井灌溉水、深井灌溉水三种;不同水源的灌溉用水水质存在一定差异;灌溉用水的水质成分与土壤的元素组成存在着一定关系,且影响水稻的产量。     

Effects of long-term irrigation with treated wastewater. Part I: Evolution of soil physico-chemical properties

The long-term impact of irrigation on a Mediterranean sandy soil irrigated with Treated wastewater (TWW) since 1980 was evaluated. The main soil properties (CEC, pH, size distribution, exchangeable cations and chloride, hydraulic conductivity) as well as the organic matter and Cu, Cr and Pb speciation in an irrigated soil and a non-irrigated control soil at various soil depths were monitored and compared during a 2 years experiment. In this first part, the evolution of the physico-chemical soil properties was described. The irrigation with TWW was beneficial with regard to water and nutrient supplying. All the exchangeable cations other than K⁺ were higher in the irrigated soil than in the reference one. A part of the exchangeable cations was not fixed on the exchange complex but stored as labile salts or in concentrated soil solution. Despite the very sandy soil texture, both saturated and unsaturated hydraulic conductivity exhibited a significant diminution in the irrigated soil, but remained high enough to allow water percolation during rainy periods and subsequent leaching of accumulated salts, preventing soil salinization. In the irrigated soil, exchangeable sodium percentage (ESP) exhibited high values (20% on average) and the soil organic C was lower than in the reference. No significant effect was noticed on soil mineralogical composition due to irrigation.     

A comparative study on energy balance and economical indices in irrigated and dry land barley production systems

This study was conducted to determine how energy balances and economical indices of barley production are affected by irrigated and dry land farming systems. Data were collected from 26 irrigated and 68 dry land barley farms. The complimentary data were collected through questionnaires filled by farmers in face-to-face interviews during 2010. The results indicated that total energy input for irrigated barley was 19,308.96 MJ ha^?1 and for dry land barley was 7,867.82. The non-renewable energy was about 66.83 and 71.02 % in irrigated and dry land systems while the renewable energy was 33.17 and 28.98 %, respectively. Energy use efficiency is energy output MJ ha^?1 divided by energy input MJ ha^?1. Energy use efficiency was 5.3 and 3.96 in dry land and irrigated systems, respectively. Although net return in the irrigated system (266.13$ ha^?1) was greater than that in the dry land system (208.64) but the benefit to cost ratio in irrigated system (1.38) was lower than that in the dry land system (1.58). Results showed that human labor as well as machinery energy inputs were the most important inputs influencing the dry land and irrigated barley production systems, respectively. The second important input in the irrigated barley was electricity (with 0.16) which was followed by water for irrigation and diesel fuel (0.14 and 0.13, respectively). In total energy consumption, the ratio of non-renewable energy was greater than that of renewable energy. Since the main non-renewable energy input was diesel, electricity, and chemical fertilizers; therefore, management and improvement in the application of these inputs would increase the proportion of renewable energy.     

Evaluation of amendments used to prevent sodification of irrigated fields

Gypsum and S are applied to soils being irrigated with Na–HCO₃ dominated coalbed natural gas (CBNG) produced water to protect soil structure and fertility. Wyoming law requires beneficial use of produced water and irrigation with CBNG produced water in the semi-arid Powder River Basin is becoming more common. Strontium isotopes were used to evaluate the effectiveness of the gypsum and S applications in preventing sodification of these irrigated soils. The isotope ratio of Sr on the cation exchange complex of irrigated soil falls between that of the gypsum amendment (0.7074) and that of local soil (0.712–0.713). Strontium isotopes indicate that, to a depth of 30 cm, as much as 50% of the Sr on the irrigated soil cation exchange sites originated from the applied gypsum amendment on a field irrigated for 3 a. This was also true to a depth of 5 cm on a field irrigated less than 1 a. Strontium isotope ratio measurements of vegetation illustrate plant utilization of Sr from gypsum amendments, thereby reinforcing the conclusions about the presence of Sr from gypsum on the soil’s exchange sites. This Sr tracing technique may be useful in a wide variety of settings where monitoring soil health is necessary, especially in settings where poor quality water is used for irrigation: a more common occurrence as demand for fresh water increases.     

Salt and nitrate exports from the sprinkler-irrigated Malfarás creek watershed (Ebro river valley,Spain) during 2010

Irrigated agriculture is a clear source of non-point pollution by salts and nitrogen species. The impact of such pollution should be quantified according to specific cases. The case of the Malfarás creek basin, a sprinkler irrigation district located in the semiarid Ebro valley in northeast Spain, has been evaluated. The main crops in the district were corn, barley and alfalfa, occupying 93 % of the irrigated area. The fate of water, salts and nutrients was evaluated by a daily water balance developed at a field scale for the natural year 2010. The yearly data of the whole set of 101 irrigated fields plus the non-irrigated area compared to the measured drainage produced a basin water balance with a low degree of error. The basin consumed 90 % of the total water input of which 68 % was used for crop evapotranspiration and the rest was lost due to non-productive uses. 16 % of the incoming water left the irrigation area as drainage water. The irrigated area was responsible for 87 % of the drainage. The average volume of drained water was 152 mm year^?1 for the whole basin area. The irrigated area drained 183 mm year^?1. The basin exported 473 kg of salt per hectare during 2010. This value was the lowest of the sprinkler irrigation areas in the Ebro valley, mainly due to the lower soil salinity. All the crops except barley received a nitrogen surplus of 10–50 % above their needs. The extra nitrogen entered the water cycle increasing the nitrate concentration in the aquifer water (150 mg L^?1) and drainage water (98 mg L^?1). In 2010 the mass of nitrogen exported by drainage was 49 kg per irrigated hectare. This value is too high for this type of irrigation system and implies that 17 % of nitrogen applied as a fertilizer was lost to drainage water. The key to decreasing the nitrogen leaching and pollution that it causes could be appropriate time-controlled fertigation along with better irrigation scheduling.     

甘肃陇中黄土高原农业灌溉耗水系数监测试验研究

选择甘肃省临洮县洮惠渠灌区为试验研究区,通过直接观读、自动监测等技术手段,获取试验灌区的引水量、退水量、土壤墒情、降水量及蒸发量等水文基础数据。以水文监测基础数据为依据,采用引排差法、水分平衡法等相结合的方法,开展了农业灌溉耗水系数试验研究。初步试验结果表明:试验灌区灌溉期平均耗水系数为0. 730,典型地块灌溉期平均耗水系数为0. 671,2016年试验灌区降水量较常年偏少13. 0%~26. 3%,总体上属轻度干旱年份。该研究成果可为甘肃陇中黄土高原区水资源管理提供技术支撑。