河北片麻岩山地黄栌幼林集水保墒措施选择

采用完全随机区组试验设计,研究了河北平山片麻岩石质山区不同组合的翼式鱼鳞坑结合集水保墒处理对黄栌幼树林地水分以及黄栌光合速率和生长指标的影响。结果表明:1)集水保墒措施最高可使降水后土壤含水量较对照提高66.76%;2)施加集水保墒措施可使黄栌光合速率较对照提高16.54%~56.48%;3)集水保墒处理可分别显著提高黄栌地径及新梢生长量80.28%~102.82%和17.52%~76.96%,而防渗克漏王+保水剂+石块覆盖(F+B+S)处理则可提高材积生长量578.04%;4)综合考虑,防渗克漏王+保水剂+石块覆盖(F+B+S)、防渗克漏王+秸杆覆盖(F+J)、防渗克漏王+石块覆盖(F+S)、自然坡面+保水剂+秸杆覆盖(Z+B+J)为该区域栽植黄栌较好的集水保墒措施。     

渭北旱塬核桃经济林径流林业技术应用研究

针对渭北旱塬地区干旱少雨的气候条件,布设试验样地,采取不同覆盖材料和集水整地措施,从土壤温度、含水量等方面分析其对核桃经济林造林的影响。结果表明,造林时采取一定的微型集水工程和覆盖措施,在集流节水、抑制蒸发和保蓄土壤水分等方面是有效的,薄膜、麦秸和杂草3种覆盖材料中,以薄膜覆盖集水效果最好,含水量达到21．74％,对0～20 cm土层增温效果明显,能够显著提高造林成活率,从而提高核桃经济林的产量和质量。     

不同覆盖条件对陇东旱塬苹果园土壤水分及果实品质的影响

为了提高苹果园的水分利用效率和果实品质,以长富2号17年生苹果树为试材(基砧为山定子,中间砧为M26),覆盖条件共设覆黑膜+覆麦草(处理Ⅰ)、覆麦草(处理Ⅱ)、覆玉米秆(处理Ⅲ)、生草(处理Ⅳ)4种处理,以清耕为对照,就不同覆盖条件对苹果园土壤集雨保墒的影响情况进行了试验研究。结果表明:在5～7月干旱期的各测定日期,处理Ⅰ～Ⅲ这三种覆盖条件下土壤各层的绝对含水量均显著或极显著高于处理Ⅳ和对照;在干旱程度较重的6月中旬,不同覆盖条件下土壤全层(0～60 cm)的绝对含水量比生草处理Ⅳ和对照的提高13.54%～37.77%,其中0～20 cm土层的绝对含水量提高25.25%～55.92%,20～40 cm土层的绝对含水量提高了5.26%～26.13%,40～60 cm土层的绝对含水量提高了7.15%～33.82%,说明集雨保墒效果明显,但处理Ⅰ～Ⅲ这三种覆盖处理间保墒效果的差别不大。处理Ⅰ～Ⅲ的果实单果质量比处理Ⅳ和对照增加6%～10%;果实中的可溶性固形物含量,处理Ⅱ与对照接近,其他覆盖处理的均显著低于对照;果实去皮硬度,处理Ⅱ的最大,为10.69 kg·cm-2,极显著高于其他处理及对照。     

栽植沟不同防渗处理对土壤肥力和苗木生长的影响

在砾质粗砂土樟子松(Pinus sylvestris var.mongolica)栽植过程中,为了提高土壤保水保肥能力和苗木生长量,研究了栽植沟不同防渗处理对土壤肥力、土壤相对含水量和苗木生长量的影响。结果表明:栽植沟塑料薄膜防渗后均提高了土壤肥力、土壤相对含水量和苗木生长量,土壤速效氮、速效磷、速效钾、相对含水量和根系密度随着栽植沟防渗面积的增加而提高,主根长度随着栽植沟防渗面积的增加而降低。不同处理中沿栽植沟沟底中线预留25 cm间距不覆盖塑料薄膜处理(处理2)的苗木主根基部粗度、胸径、冠幅和株高最高,分别为14.20、8.47、138.12和152.48 cm,较对照(CK)不做任何防渗处理的主根基部粗度、胸径、冠幅和株高分别提高了70.67%、89.73%、24.66%和33.16%,差异均达到极显著水平(P0.01)。     

沙漠生物结皮层覆盖对风沙土水分蒸发特征的影响

生物结皮作为流动沙丘固定的标志之一,影响着风沙土水文的变化特征。本文研究结果表明：生物结皮覆盖直接影响着风沙土水分的再分配过程;不同类型生物结皮对土壤自然含水状况和降水再分配的影响不同。生物结皮覆盖对0～5cm土层的土壤自然含水量具有一定的保护作用。同时,随着土层深度的增加,不同覆盖状态下,土壤自然含水量发展趋势不同。沙土表层覆盖方式和降水条件不同时,生物结皮层覆盖均不能有效地阻止水分的蒸发过程,并因生物结皮类型的差异,表现出不同的变化趋势。     

干旱胁迫对荆芥的形态及其生理指标的影响

为掌握荆芥的耐旱性,以荆芥3年生幼苗为材料,研究干旱胁迫下荆芥的形态及其叶片含水量、丙二醛(MDA)、膜相对透性和脯氨酸含量等指标的变化。结果表明,干旱胁迫下,荆芥的株高、冠幅和叶面积均低于对照水平。随着干旱胁迫时间的增加,MDA、电导率和脯氨酸含量均呈现不断增加的趋势,干旱60d后,分别比对照高出35.56%(P0.05)、98.56%(P0.01)、174.37%(P0.05)。荆芥耐旱能力较强,可忍耐60d以上的自然干旱。     

兰州北山地区不同集水材料集水效率及对土壤水分变化的影响

1998—2002年在兰州北山人工林地进行了不同集水材料集水效率与集流效果对比试验，分析不同集水材料的使用期、成本，并对降水量与土壤下渗深度之间的关系进行了探讨。结果表明：7种集水材料的集水效率均大于对照，集水效率不受坡向的影响，石棉瓦、油毛毡是集水材料的首选；在有效降水的条件下，塑料膜、石棉瓦、处理土面集水效率明显高于对照黄土夯实；0—40cm土层，塑料膜、石棉瓦土壤含水量高于处理土面和黄土夯实，60cm以下土层，使用各种集水材料土壤含水量没有差异。     

旱坡地枣园集水增墒效果研究

晋西黄土丘陵区枣树集水栽培是解决干旱问题的主要措施。人工模拟径流蓄集试验表明 ,当径流集蓄至 4 0 mm～ 80 mm时 ,增墒持续时间就能维持 30 d左右 ;当径流集蓄超过 80 mm后 ,增墒持续时间能够稳定在 4 5d左右。一次天然降雨 1 5mm,集水枣园土壤水分有效增墒效果能够维持 1 0 d左右 ;1 5mm<降雨量 <4 0 mm,土壤增墒时间为 1 0 d～ 30 d。生长期内 ( 4月— 1 0月 )降雨量达 30 0 mm时 ,集水枣园水平沟集蓄效果开始显著 ,其土壤水分含量比对照平均提高 1 .30 %左右 ;低于 30 0 mm时 ,集流增墒效果不显著。当生长期降雨量超过 4 0 0 mm时 ,坡地枣园土壤水分含量比对照提高 1 .7个～ 1 .8个百分点 ,覆盖能提高土壤水分含量 1 %左右。     

油菜素内酯对沙棘抗旱生理的影响

采用盆栽控水、根系浸蘸和叶面喷施不同浓度油菜素内酯(BRS)的方法,对黄土丘陵区主要造林树种沙棘苗重要保护酶活性、重要渗透调节物质以及质膜稳定性进行了测定和分析.结果表明:沙棘苗经BRS0.1～0.4 mg/L处理后,SOD和CAT活性在轻度干旱(土壤含水量12%～13%)和重度干旱(土壤含水量7%～8%)下,虽较清水对照升高,但无显著差异;在轻度干旱下,POD活性0.3 mg/L处理显著高于对照,类胡萝卜素含量0.1～0.3 mg/L处理较对照极显著增加;在轻度和重度干旱下,脯氨酸含量较对照增加不显著,可溶性糖含量0.3和0.4 mg/L处理显著高于对照,质膜相对透性,较对照显著降低,丙二醛含量在轻度干旱下,较对照显著降低,重度干旱下降低不显著.综合以上结果:BRS处理提高了沙棘苗的抗旱性.     

荒漠藻人工生物结皮固沙成效调查

本文探讨了荒漠藻人工生物结皮和固沙措施的关系,结果表明：固沙措施不同,生物结皮形成特征不同。单纯的人工造林固沙措施,生物结皮出现的样方概率平均为66.5%,生物结皮盖度平均为68.8%。而采取沙障固沙造林措施,生物结皮出现的样方概率平均为86.3%,生物结皮盖度平均为70.2%。     

Influence of various in situ rainwater harvesting methods on soil moisture and growth of Tamarix ramosissima in the semiarid loess region of China

The influence of different in situ rainwater harvesting and moisture conservation methods on soil moisture storage and growth of Tamarix ramosissima was studied in the semiarid loess region of China from 2002 to 2004. The treatments included control (T1), trench (T2), saucer covered by plastic film (T3), bare ridge and bare furrow (T4), plastic-covered ridge and bare furrow (T5), and plastic-covered ridge and gravel-covered furrow (T6). The results indicated that soil water storage for the T5 and T6 was significantly higher than the control. The T6 treatments produced the highest amount of soil water storage, 18–137 mm more than the controls at soil depth of 0–100 cm and 40–75 mm at soil depth of 100–200 cm. No significant differences in soil water storage were found between the T2, T3, T4 and the control treatments at soil depth of 0–100 cm, but soil water storage at soil depth of 100–200 cm was significantly higher for the T2, T3, T4 treatment than the control.Rainwater harvesting and moisture conservation treatments increased growth of T. ramosissima, tree height was significantly higher for the rainwater harvesting and moisture conservation treatments than the controls. Tree height, crown diameter and collar girth for the T6 treatments increased by 70, 57 and 79% as compared to the controls. No significant differences in crown diameter and collar girth were observed between T1, T2 and T3 or T4 and T5 treatments in some years. The effectiveness of the different treatments for the tree height, crown diameter and collar girth was in the order of T6, T5, T4, T3, T2 and T1.     

Influence of rain water harvesting and conservation practices on growth and biomass production of Azadirachta indica in the Indian desert

A field experiment was conducted to investigate the influence of various rain water harvesting and conservation techniques on soil moisture storage, growth and biomass production of Azadirachta indica (neem) in the Indian desert. The treatments were as follows: control; weed removal; weed removal plus soil working; saucers of 1.0 m diameter; saucers of 1.5 m diameter; saucers of 1.5 m diameter covered with mulch around the trees; bunding around each tree in a checkerboard design; inter-row slopes of 20%. The treatment with inter-row slopes of 20% produced the highest amount of soil moisture storage, a four times increase in total biomass of a 26-month-old neem plantation (from 1.69 to 6.39 t ha⁻¹), a 4.5 times increase in root mass (from 0.43 to 1.92 t ha⁻¹) and a 70% increase in tree height, as well as an appreciable enhancement in all the growth parameters. The treatment with larger saucers (1.5 m diameter) combined with a surface mulch was equally effective. Growth increases owing to the other water harvesting treatments were lower, though significantly better when compared with the control. The various treatments significantly improved the water use efficiency of neem.     

不同土壤水分管理措施对油茶生长的影响

为给油茶林地土壤水分管理和节水灌溉提供技术支撑,以6年生长林4号油茶林为试验材料,设置自然状况、干旱胁迫、干旱覆盖这3个处理措施,就不同土壤水分管理措施对油茶果实、花苞、叶片解剖结构的影响情况进行了试验研究。结果表明:在自然状况、干旱胁迫、干旱覆盖这3种处理下,油茶果高、果径、花径、花高的生长量间均存在极显著差异;在自然状况及干旱覆盖处理下,油茶叶片各解剖结构参数与不同深度土层的土壤含水率间均呈弱相关;在干旱胁迫处理下,油茶叶片解剖结构中的下表皮及叶片总厚度与不同深度土壤含水率间均呈中度相关(0.5r0.8)。在自然状况下,不同深度土层的土壤含水率与油茶果径、花径、花高生长量间均呈弱相关,而与其果高生长量呈中度负相关(0.5r0.8);在干旱胁迫与干旱覆盖处理下,其花径、花高与4种深度的土壤含水率间均呈高度负相关(0.8r1.0);在干旱覆盖处理下,其果径与4种深度土层的土壤含水率间均呈中度负相关(0.5r0.8);在干旱胁迫处理下,其果高与4种深度土层的土壤含水率间均呈中度正相关(0.5r0.8)。     

干旱、半干旱黄土区庭院果园节水灌根技术效应研究

水分是制约西北干旱、半干旱区农林业发展的一个关键因子。由于该区天然降雨量少,且时、空分布极不均匀,再加上地下水资源严重匮乏,给当地群众的生活和生产带来了极大困难（陈昌毓,１９９５;赵松龄,１９９６）。通过雨水集流措施,把大气降水贮纳起来,结合节水灌溉和抗旱栽培等综合配套技术,在无灌溉条件的农村建立以优质果树为主的家庭生态果园,不仅提高了土地和水资源的使用效率,而且也给农户带来了一定的经济效益。本文对插管（瓶）灌根、双瓶渗灌（赵岷阳等,１９９６;初长海,１９９７）等新型节水灌溉方法及果带覆膜等配套…     

国内外土壤蓄水保墒技术研究动态

本文在研究分析国内外大量文献的基础上介绍了集水节水技术和土壤蓄水保墒技术的研究概况,为干旱半干旱地区水资源的合理开发利用提供了科学依据。     

干旱半干旱沙区人工植被与土壤水分环境相互作用关系研究进展

土壤水分在干旱、半干旱沙区人工植被恢复、植物生长和群落演替过程中起着重要作用。文中综述了我国主要沙化地区人工固沙植被土壤水分状况和动态的研究现状, 分析了土壤水分的时空格局及其影响因子; 探讨植被冠层、生物结皮、植物根系对土壤水分的调控作用和影响机理以及干旱、半干旱沙区人工植被土壤水分空间异质性及相关问题; 最后提出人工植被区的土壤水分动态模拟预测、土壤—植被—大气系统水量平衡和水分循环以及空间尺度扩展等问题应是未来的研究重点。     

Water harvesting in a ‘runoff-catchment’ agroforestry system in the dry lands of Ethiopia

A major production constraint in arid and semiarid areas of Ethiopia is a lack of water for crop growth. Run off water can be harvested by channeling it into micro- catchments (MC) where it slowly infiltrates into the soil. The increased moisture provides more plant growth in these dry lands. An experiment using MC was conducted in eastern Ethiopia to study the growth of four multipurpose tree species intercropped with grass. Trees and grass were grown in 25 m² and 100 m² MC. Plant height, root collar diameter, and mortality rate of trees were determined 12 months after planting. Dry matter yield of grasses and trees were measured and nutrient analysis of plant tissues was determined. In a separate experiment the biomass of trees was determined after 2.5 years of continuous growth without grass competition. Soil moisture, organic matter, texture and bulk density of the soils were also determined. Mean tree height was 10% greater in the 100 m² than in the 25 m² MC. Root collar diameter and survival rate showed similar increase with 13% and 7.8% respectively. Acacia saligna and Leucaena leucocephala showed better growth in both plot sizes than the indigenous Acacia seyal and Acacia tortilis. The dry matter yield of grass (Panicum maximum) was over 12 tons/ha and 8 tons/ha in the 100 m2 and 25 m2 plots respectively. Soil moisture content was greater in MC than in control plots with no water harvesting structures with 31% and 24% during the wet and dry seasons respectively. The use of water harvesting can improve fodder production and carrying capacity of the dry lands of Ethiopia.     

降雨对干旱半干旱地区土壤微生物影响研究进展

未来气候变化预示着降雨时间和数量的变化。降雨是干旱半干旱地区最重要的水分来源,降雨格局的变化将直接影响该区域生态系统的稳定性,而土壤微生物作为敏感指标多用来监测生态系统的稳定性。文中综述了降雨对干旱半干旱地区土壤微生物生物量、多样性的直接影响,以及其通过改变土壤水分、土壤空气和植被生长等对土壤微生物产生的间接影响,其中还可能伴随着其他因素的干扰,如土地利用方式、温度、海拔等。通过了解降雨格局变化对干旱半干旱地区土壤微生物的影响,可以更好地预测未来气候变化对该地区生态稳定性的影响。指出了降雨对干旱半干旱地区土壤微生物影响研究中存在的问题,并对未来研究进行了展望。     

土壤温度和水分变化对川西云杉幼苗氮和磷含量的影响

【目的】研究不同梯度的土壤温度和水分对川西云杉幼苗生长性状和各器官氮和磷含量的影响,以期为全球气候变暖背景下解释川西云杉树线形成的原因提供参考和数据积累。【方法】以5年生川西云杉幼苗为试验材料,采用人工气候室结合嵌套设计,设置5个土壤温度梯度(2、7、12、17、22℃)和3个土壤水分梯度(干旱处理、正常水分含量处理、饱和水分含量处理)。每处理9株幼苗,共135株幼苗。实验处理4个月后,测定并比较分析不同梯度的土壤温度和水分对幼苗的生长性状、各器官干物质含量、各器官全氮、全磷浓度和含量以及土壤全氮和全磷浓度的影响。【结果】土壤温度处理对幼苗基径和株高生长量均无显著影响,而土壤水分处理对幼苗株高生长量有显著影响;在2℃和7℃土壤温度干旱处理下显著降低了幼苗的株高生长量,但随着土壤温度的升高其影响效应不显著。土壤温度处理对土壤氮和磷浓度无显著影响,而干旱处理显著升高了土壤氮和磷浓度。川西云杉幼苗各器官的氮和磷浓度以及当年生叶氮含量随土壤温度降低显著降低;干旱和饱和水分处理显著降低了当年生叶和当年生枝的氮浓度,饱和水分处理显著降低了当年生叶的磷浓度,干旱处理显著降低了当年生枝、茎和根的磷浓度,干旱和饱和水分处理显著降低了当年生叶和根的氮和磷含量,且随着土壤温度升高影响效应更显著。【结论】在短期内,土壤低温对川西云杉幼苗的生长性状没有明显的制约作用,但对川西云杉幼苗各器官的氮和磷浓度及含量影响显著,尤其是当年生叶和根的氮和磷浓度及含量。在川西地区,低温、干旱等极端气候胁迫导致的云杉幼苗氮、磷含量的不足很可能是限制川西云杉垂直分布的重要因素。此外,土壤温度和水分处理存在显著的交互作用,随着土壤温度的降低,水分胁迫对幼苗各器官氮和磷含量的影响由显著变得不再显著,说明随着海拔升高,与水分因子相比,土壤低温成为造成云杉各器官营养元素亏缺的主导因子。     

Performance of Drought Tolerant Maize Varieties under Water Harvesting Technologies in the Coastal Region of Kenya

The average annual rainfall in coastal Kenya is 450–700?mm per annum in most places while the total annual evapotranspiration is 1200–1800?mm. In arid and semi-arid lands (ASALs), farmers grow maize varieties for medium to high rainfall zones without considering the need for water harvesting to enhance crop yield. To address the moisture constraint, a study was conducted to evaluate the performance of drought tolerant maize varieties under different water harvesting technologies (Zai pits, tied ridges and conventional). The treatments were laid out in a split - plot design with water harvesting methods as the main plots and maize varieties as the sub-plots. The response of four maize varieties (DK8031, DUMA 43, KDV1 and PH4) to three water harvesting technologies was evaluated. Variety Duma 43 produced the highest grain yield (P < 0.05) compared to the other varieties whereas yields for Zai pits and tied ridges were higher (P < 0.05) than for conventional treatment. Economic analysis revealed a higher gross margin for tied ridges than for Zai pits. Conventional planting showed a negative gross margin under the ASAL conditions. The variety DUMA 43 was selected for yield and cob size components whereas PH4 was selected for grain recovery when pounded and high stover biomass.