不同铺设年限沙柳沙障的防风固沙效益研究

以铺设于2000年和2003年沙柳沙障为研究对象,研究了不同铺设年限的沙柳沙障对沙漠地区风速特征的影响,以探讨沙柳沙障的防风固沙效果。结果表明:随着沙柳沙障年限的增加,设障沙柳沙障样地的防风效能增大,2个设障年限样方的防风效能均在10cm处达到最大,100cm处最低;设障沙柳沙障使地表粗造度显著地提高,2000年试验样地与2003年试验样地的地表粗糙度值分别是对照粗糙度值的2.35倍和3.69倍;2000年铺设的沙柳沙障内的风速廓线曲线比2003年的变化更显著。     

野外栽培大球盖菇效益好

晚秋作物结束后 ,选择荫畦、背风向阳的田块栽培大球盖菇 ,既可大大提高土地利用率和养地效果 ,又可省土、省成本 ,获得高效 ,一举两得。具体栽培技术如下 :1　栽培场地与时间　选择近水源 ,便于排灌、背风向阳的冬闲田、菜园地、果园地等作栽培场 ,整成高 30cm、宽 1m ,长度不限的龟背形畦床 ,畦间人行道宽 40cm ,播前翻土晒白 ,使土壤熟化 ,再用农药除杂、灭虫。较为理想的播种时间 :秋菇 9月下旬至 1 0月上旬 ,春菇 2月中下旬。2　培养料选备与处理　①干纯稻草 1 0 0 % ;②干稻草 80 % ,干木屑 2 0 % ;玉米芯、玉米秆、豆秆等均可。播种…     

不同固沙植被下沙丘土壤水分动态比较

以毛乌素沙地覆盖度90%的油蒿、50%～60%的沙柳、35%～40%的樟子松固定沙丘为研究对象,流动沙丘为对照,采用自动监测系统实时监测降雨、0～200 cm土壤含水量及200 cm以下渗漏量,分析5—11月不同固沙植被下沙丘土壤水分动态差异,以期为固沙植被稳定性评价提供参考。结果表明:较低覆盖度樟子松与高盖度油蒿、沙柳相比更具固沙优势。3种固沙植被表层0～30 cm土壤水分受降雨影响大,对20 mm降雨均产生响应;60～200 cm土壤水分时间变化特征存在差异,樟子松与对照变化趋势一致,油蒿和沙柳仅对40 mm降雨产生响应;0～200 cm土壤水分垂直变化没有相同规律,变异性较大,樟子松变幅最大,为(5.03±3.09)%;深层渗漏特征基本一致,均有极少量水分渗漏到200 cm以下。     

横坡垄作和秸秆覆盖对坡耕地水土养分流失的影响

针对南方坡耕地的水土养分流失问题,通过田间小区试验,以顺坡垄作为对照(CK),研究横坡垄作(KF)和横坡垄作+秸秆覆盖(BMP)对坡耕地大豆产量、土壤和水分养分流失的影响。结果表明:与CK相比,BMP处理降低了径流量,并显著减少了径流水中总氮和硝态氮;BMP处理显著提高了土壤中的土壤含水率、有机质、硝态氮和铵态氮;BMP处理的大豆产量和秸秆产量分别增加了2.13%和1.94%;而单纯的横坡垄作(KF)对坡耕地的养分流失效果是有限的。综上,横坡垄作并加以秸秆覆盖可以更好地减少水土养分流失,提升土壤养分能力和作物产量,是适用于南方坡耕地的有效农耕措施。     

日光温室桃丰产优质栽培技术

1 日光温室的建造 日光温室栽培属设施栽培,需选在背风向阳,地势平坦,地下水位较低,土壤肥沃、疏松,有灌溉条件,交通便利的地块.温室一般要求坐北朝南,东西长50～100m,温室跨度6～8m,后墙厚60 cm,两侧山墙厚60 cm,中脊高3～3.2m,后墙高2.3～2.6m,后屋坡长1.3～1.5m,其仰角360,钢筋拉花成拱圆形采光面的间架前底脚670,至中脊高分别有三个采光角460、300、180,屋面坡的水平投影应在1～1.2m.     

食品袋栽培平菇技术

随着食用菌的迅速发展,农作物的秸秆被广泛利用。玉米芯、玉米秆、豆秸、稻草、废棉等都视为栽培平菇价廉质优的原料,但由于这些原料颗粒性差,长度不等,硬度大,容量小,给常规塑料袋栽培带来不便。笔者几年来采取聚氯乙烯背心式食品袋,用废棉、玉米芯、豆秸、稻草等原料栽平菇,均收到了良好的效果,每1O0kg原料的塑料袋投资仅1.5～2.5元,每人每天可栽200～300kg。现将栽培要点介绍如下: (一)原料处理 整株玉米秆、稻草、高粱秆用铡草机或铡刀截成2～10cm小段。整玉米芯、整豆秸用车辊碾压,玉米芯碎成1～10cm小块,豆秸碾成杆揉软即可。原料粗细比例以4分细6分粗为宜,以防栽培料中空隙太大,菌丝长势弱。棉子壳、花生壳、豆角皮等颗粒性较好的原料,可不作处理直接使用。     

早熟葡萄日光温室栽培的关键技术

近年来随着市场经济的发展 ,生活水平的提高 ,塑料薄膜的应用 ,果品淡季供应的超高效益 ,使葡萄设施栽培得以迅速发展。现将葡萄日光温室栽培的关键技术介绍如下。1　温室建造1 .1　场地选择　温室的地点最好选择在地势平坦、背风向阳、土壤疏松肥沃、地下水位较低、排灌方便、交通便利、具温暖小气候的地方。1 .2　结构类型　目前我国日光温室的结构类型很多 ,但生产中应用较多的有两种 ,即南北走向的一斜一立式和坐北朝南东西走向的拱圆式。前者的优点是土地利用率高 ,室内光照分布比较均匀 ,缺点是固定薄膜的方法较复杂 ;后者的优点是可…     

无纺布在草莓育苗中的应用

草莓育苗主要采用匍匐茎繁殖的方法.繁殖过程中会滋生大量杂草.人工拔草用工量大,使用除草剂易造成土壤板结,且对子苗有不良影响.无纺布是一种柔软、轻质,能降解、环保、透水透气不透光的黑色膜,草莓地铺设后除草效果好.草莓苗在冬前或春季定植,定植后即可铺设无纺布,行间铺设无纺布,草莓苗位于两幅无纺布交接缝中间.无纺布宽度应略大于行距,以便相接的两幅无纺布互相压边.     

保护地蔬菜沙培试验

我国有广阔的沙漠、沙地、沿海沙滩及附近重盐碱地.在这些地区,用传统的土壤栽培法难以生产鲜菜,多靠长途调运供应当地市场,质次价高。这些地区吃菜非常困难。为解决此问题,我们于1987年春邀请美国亚利桑那州立大学著名的无土栽培专家来华讲学并帮我们建起了小型的滴灌式沙培设施并连续进行了7茬与土培的对比试验,均取得了很好的效果。根据我国国情,为了进一步提高沙培的效果及简化操作技术,我们于1988年秋又建起了“水气式”沙培设施,连续进行了5茬沙培试验,也取得了很好地栽培效果。历茬沙培黄瓜比土培的增产60％以上,比其它基质栽培增产6.5％以上,历茬沙培西红柿比土培的增产40.2％以上,比其它基质培增产12.1％以上。沙培叶菜类增产幅     

不同沙土比例对彩叶草嫩枝扦插的影响

以1a生彩叶草为试材,研究了全土、25％沙、50％沙、75％沙、全沙5种不同混合比例基质对其嫩枝插穗生长及叶片特性的影响,以期确定彩叶草嫩枝最佳的扦插沙土比例.结果表明:50％沙的处理效果较好,在叶绿素、株高、茎粗、生根数、根冠比、氮含量和成活率指标方面都优于其它处理,不仅能使插穗保持较高的生长量,而且叶片色素含量最高,商品价值高.     

压砂西瓜间套马铃薯油葵栽培试验

针对宁夏压砂西瓜产业发展的需要,探索压砂西瓜高效栽培模式技术(间套)。结果表明:压砂西瓜套种油葵共生期长,前期油葵与西瓜争光和肥水,西瓜坐瓜和大小受限制,影响西瓜产量;压砂西瓜套种马铃薯共生期长,马铃薯与西瓜争光、争肥水不明显,西瓜坐瓜和大小不受限制,西瓜产量不受影响,每667 m2套种马铃薯生产比对照多收入231.2元。     

三种灌木抢墒植苗临界土壤含水量的研究

为了定量确定宁夏中部干旱风沙区主要旱作造林树种植苗造林成活率与土壤墒情的关系,在宁夏盐池县人工模拟不同土壤墒情梯度,开展了常用旱作造林树种柠条、花棒、杨柴3种灌木裸根苗植苗试验。结果表明:在宁夏河东沙地盐池县,当沙地土壤含水量在≤5.5%时,3种灌木旱作植苗造林成活率及苗木生长受土壤含水量影响较大,不适宜造林;当土壤含水量≥9.32%时造林,3种灌木植苗造林成活率可以达到造林验收标准,苗木高生长虽然随土壤含水量的增加,有所提高,但受土壤水分影响的程度不再明显。     

滇西北松口蘑菌塘的生态因子调查

以滇西北丽江市拉市乡松口蘑(Tricholoma matsutake)产地为例,进行了松口蘑菌塘生态因子的调查。结果发现:(1)松口蘑菌塘多集群分布于狭窄的山脊及西南坡,坡面坡度在30~60°之间,上层云南松荫蔽度0.4~0.6,下层高山栎、黄背栎等灌木丛荫蔽度达0.7~0.9,落叶层及腐质层1~6 cm;(2)出菇期间菌塘地表附近空气的平均温度14.1℃,平均相对湿度78.7%;(3)出菇期间菌塘的地下温度在15.0~20.5℃之间,西南坡的菌塘温度相对较高;(4)菌塘土壤的含水量比非菌塘土壤的含水量低,出菇期间平均低16.7%;(5)菌塘土pH约为5.5,比非菌塘土低7.9%;(6)菌塘土除全钾的含量比非菌塘土高之外,其余营养成分均比非菌塘的低。     

Sod establishment and turfgrass growth as affected by urea–formaldehyde resin foam soil amendment

Urea–formaldehyde resin foam (UFRF) has recently been introduced as a soil amendment for turfgrass culture. A field study was performed to evaluate the impact of UFRF on soil physical and chemical properties, sod establishment and turfgrass shoot and root growth. Treatments included a non-amended, sandy loam soil and the same soil amended with UFRF at a rate of 20% (v/v) incorporated into the upper 0.1 m of the substrate. Physical and chemical analyses of the two substrates involved the determination of bulk density, total porosity, air-filled porosity at 0.4 m, moisture release curve, pH and electrical conductivity. Turfgrass growth was determined through several measurements that included shoot growth rate, root growth rate and monitoring of three root architecture parameters namely, total root length, total root area and mean root diameter. Turfgrass establishment was evaluated by measuring the vertical force applied to detach the sod from the substrate.UFRF amendment did not influence pH and EC and provided minimal alterations (non-significant) in soil physical properties by slightly increasing total porosity, easily available water and air-filled porosity, and by reducing bulk density. The impact of UFRF amendment improved cumulative clipping yield in five sampling dates but root growth and sod establishment rate were better than the control only on one sampling date. There appears to be limited benefit in amending soil with UFRF.     

毛乌素沙地沙芥和斧形沙芥根系分布特征

以毛乌素沙地沙芥和斧形沙芥为试材,采用全挖法,研究了其根系周围土壤含水量变化、根系分布及水平根系空间分布特征。结果表明:在自然生境中,沙芥和斧形沙芥1a生植株根系周围的平均土壤含水量分别为(2.68±0.11)%、(2.50±0.45)%;2a生的分别为(3.13±0.46)%、(1.90±0.68)%。沙芥和斧形沙芥主根垂直,水平根系数目较少、但长度极其发达。沙芥和斧形沙芥2a生主根长均约为120cm,最长水平根分别为380、400cm,水平根累计总长分别为1 590、3 340cm。沙芥和斧形沙芥2a生水平根系均在深度40～60cm、距主根0～40cm的空间范围内分布最多,均在40～60cm的土层深度分布最大,因此,沙芥和斧形沙芥主要依靠延长水平根系寻找远距离水源来适应低土壤含水量环境,斧形沙芥比沙芥更能适应低土壤含水量。     

The influence of moisture regime on greenhouse rose production in various growth media

The effect of irrigation regimes and growth media on the production and quality of ‘Baccara’ roses was examined in a greenhouse during the 1969/70 and 1970/71 seasons. The media tested were (a) sandy loam, (b) sandy loam mixed with peat moss, (c) vulcanic scoria (tuff), (d) sandy loam placed on top of the local soil; all except (d) were in raised benches. Two levels of fertilizers were examined in the tuff media. The irrigation treatments in the soil media were established according to pre-irrigation water suction in the range 5 to 50 centibars (cb). In the tuff media the irrigation treatments were scheduled at different frequencies ranging from eight irrigations per day to one irrigation every 2–3 days.Maximum flower production was obtained in sandy loam which was placed on top of the local soil and irrigated so that the soil water suction did not rise above 5 cb. Flower length was unaffected by the irrigation regime in this growth medium.Flower production in the raised benches dropped when the water suction was kept below 20 cb or when it was allowed to rise to 50 cb. On the other hand, the highest percentage of long-stem flowers was obtained when the water suction was maintained below 5 cb.No significant difference in flower production was found between 5–8 and 2 irrigations per day in the tuff media. Maximum yield from these treatments was significantly lower than that in the non-raised soil benches. An increase in fertilizer level had no effect on flower production or quality.The flowering buds were relatively small at the beginning of winter and became larger toward spring. Only minor effects of growth media and moisture regimes on bud weight were found.     

Applying spent coffee grounds directly to urban agriculture soils greatly reduces plant growth

There are frequent anecdotal recommendations for the use of locally produced spent coffee grounds in urban agriculture and gardens, either through direct soil application or after composting with other urban organic wastes. This study investigates the scientific basis for direct application of spent coffee grounds (SCG) and the influence of different: (i) plant pH and nitrogen preferences, (ii) soil types, and (iii) application rates. We specifically consider impacts upon plant growth, soil hydrology and nitrogen transformation processes.We grew five horticultural plants (broccoli, leek, radish, viola and sunflower) in sandy, sandy clay loam and loam soils, with and without SCG and fertilizer amendments. The same horticultural plants were grown in the field with 0, 2.5, 5, 10 and 25% SCG amendment rates. Plant biomass growth was related to soil pH, soil moisture, nitrogen concentration and net mineralization, as was weed growth after harvesting.All horticultural plants grew poorly in response to SCG, regardless of soil type and fertiliser addition. Increasing SCG amendment significantly increased soil water holding capacity, but also decreased horticultural plant growth and subsequent weed growth. There was evidence of nitrate immobilization with SCG amendment. Growth suppression was not explained by soil pH change, or nitrogen availability, so is more likely due to phytotoxic effects.Fresh SCG should not be used as a soil amendment in ‘closed loop’ urban food production systems without consideration of potential growth suppression. Further research is required to determine the optimal composting conditions for SCG and blends with other organic wastes.     

板栗树体水分与土壤水分动态变化的相关分析

通过观测板栗的根、枝、叶及栗园土壤水分含量的动态变化发现：根、枝、叶组织水分含量的变化随着栗园土壤含水量的变化而变化；30cm土层为板栗根系的主要吸水层；北方山地栗园，春季每15－20天需要进行一次灌水，以满足板栗树体生长发育对水分的需求。     

Yield and quality of carrots as affected by soil moisture and N-fertilization

Summary

High yield and quality are important factors for growers of carrots (Daucus carota L.). The objective of this study was to determine optimum soil moisture and N-fertilization to maximize carrot yield and external quality (i.e. the quantity of split and forked roots). The experiment was carried out in a microplot field installation with three levels of soil moisture (75, 50 and 25 vol% available field capacity (AFC)) on a sandy and a loamy soil over the last 16 and 11 weeks of the cropping period, respectively. Two movable roofs covered with polyethylene foil were used to maintain the three soil moisture levels, which were measured in all combinations with two levels of nitrogen fertilization (0 and 150 kg N ha^-1). The highest total yields were reached at both soil types at 75 vol% AFC and 150 kg N ha^-1. The quantity of forked carrots was more affected by reduced soil moisture on the sandy soil than on the loamy soil. The mass fraction of split roots increased with increasing soil moisture on both soil types and a significant interaction was calculated between soil type and fertilization. The mass of split roots on the sandy soil was significantly increased by fertilization.     

Assessing topographic patterns in moisture use and stress using a water balance approach

Through its control on soil moisture patterns, topography’s role in influencing forest composition is widely recognized. This study addresses shortcomings in traditional moisture indices by employing a water balance approach, incorporating topographic and edaphic variability to assess fine-scale moisture demand and moisture availability. Using GIS and readily available data, evapotranspiration and moisture stress are modeled at a fine spatial scale at two study areas in the US (Ohio and North Carolina). Model results are compared to field-based soil moisture measurements throughout the growing season. A strong topographic pattern of moisture utilization and demand is uncovered, with highest rates of evapotranspiration found on south-facing slopes, followed by ridges, valleys, and north-facing slopes. South-facing slopes and ridges also experience highest moisture deficit. Overall higher rates of evapotranspiration are observed at the Ohio site, though deficit is slightly lower. Based on a comparison between modeled and measured soil moisture, utilization and recharge trends were captured well in terms of both magnitude and timing. Topographically controlled drainage patterns appear to have little influence on soil moisture patterns during the growing season. In addition to its ability to accurately capture patterns of soil moisture in both high-relief and moderate-relief environments, a water balance approach offers numerous advantages over traditional moisture indices. It assesses moisture availability and utilization in absolute terms, using readily available data and widely used GIS software. Results are directly comparable across sites, and although output is created at a fine-scale, the method is applicable for larger geographic areas. Since it incorporates topography, available water capacity, and climatic variables, the model is able to directly assess the potential response of vegetation to climate change.