桃树林间作鸡腿菇技术探讨

采用不同的培养料配方,对桃树林和大棚(CK)内栽培的鸡腿菇进行了研究。结果表明,各配方处理桃树林内枝培的鸭腿菇均能正常生长．且优于对照,但存在差异,配方B效果最佳,表现为菌丝生长快、洁白、健壮、出菇早、子实体性状优良、产量高。     

WaLIS—A simple model to simulate water partitioning in a crop association: The example of an intercropped vineyard

The introduction of cover crops in vineyards is being tested as it mitigates some undesirable environmental impacts of these cropping systems, such as surface runoff and soil erosion. In some cases, it could even reduce an excessive vegetative vigour of grapevine. However, most of time, wine growers are worried that severe competition for soil resources between the intercrop and grapevines could impair grape yield and quality. WaLIS (Water baLance for Intercropped Systems), a simple model simulating the water resource partitioning in such an association was designed to evaluate and optimize the water regime in intercropped systems.The model is presented and evaluated in this paper in three situations: the same grapevine cultivar (cv. Aranel) with either bare soil, or a temporary intercrop (barley) or a permanent intercrop (tall fescue). All three situations are located in the south of France. It is based on an existing model, designed to simulate the water regime of a bare soil vineyard, which was adapted to take into account the specific features of intercropped systems. Hence it includes a two-compartment representation of the soil particularly adapted to row crops. The simulation of a grass cover growth and its transpiration were added. Finally, particular importance was dedicated to the simulation of surface runoff which was the main source of the original model deviation during the winter period and made difficult multi-year simulations. Now, the model appears to be able to evaluate perennial cropping systems and provide decision support.The WaLIS model simulated the water available for both grapevine and intercrop well, and it proved to be efficient in most of the tested situations and years. The modelling of the water stress experienced by both crops was also generally good and all water fluxes simulated by the model were realistic. The main observed deviation in the simulation of the water soil content occurred during winter, i.e. outside the grapevine growth period. It was very likely due to the use of a constant parameter value for the surface runoff which did not take into account of changes in the soil surface and their effects on water infiltration.Finally, the analysis of sensitivity made on the WaLIS model showed that it is robust and sensitive to a few parameters, which drive the maximal grapevine transpiration and soil evaporation or are linked to the surface runoff simulation. The work also revealed how a good estimate of the total soil water available for each crop is crucial. This model, easy to use and parameterise, can provide sound management advice for designing valuable intercropped cropping systems.     

大棚番茄连续定位套蒜第3年度土壤微生物数量和酶活性的变化

【目的】明确大棚番茄连续定位套蒜第3年度土壤微生物数量和酶活性的变化及其相关性。【方法】试验设单作番茄、套作大蒜、套作青蒜3个处理,定期采集土样并分析微生物数量和酶活性的变化。【结果】套蒜可增加土壤的微生物数量,3个处理土壤微生物数量由多到少的顺序为套作青蒜>套作大蒜>单作番茄;与单作番茄相比,连续3年套蒜能显著提高土壤过氧化氢酶、蔗糖酶、脲酶和碱性磷酸酶4种酶的活性,过氧化氢酶活性表现为套作大蒜>套作青蒜>单作番茄,蔗糖酶、脲酶和碱性磷酸酶活性表现为套作青蒜>套作大蒜>单作番茄。套作大蒜和青蒜的土壤微生物数量与酶活性的相关性以及不同土壤酶之间的相关性较单作番茄土壤更显著。【结论】大棚番茄套蒜是丰富土壤微生物多样性和酶活性的有效措施,连续3年定位套蒜可以改善大棚番茄连作带来的土壤微生物数量少、土壤酶活性低的问题。     

间作小麦、蚕豆的产量和竞争力对供水量和化感物质的响应

为了寻求解决间作群体受化感物质抑制作用的理论依据, 本研究通过盆栽试验, 探讨了不同供水水平下(田间持水量的45%、60%和75%), 小麦根系分泌物间甲酚对单作小麦、单作蚕豆、小麦间作蚕豆生物产量、经济产量和两种作物共生期间竞争力的影响。结果表明: 60%和75%供水水平下, 间作小麦生物产量和经济产量较单作显著提高, 45%供水水平下间作小麦经济产量低于单作; 不同供水水平下, 间作蚕豆的生物产量与相应供水水平的单作相比, 增加显著。间甲酚对小麦、蚕豆的产量均具有化感负效应, 间作具有一定弱化间甲酚对蚕豆化感负效应的作用。45%、60%和75%供水水平下, 间甲酚使间作小麦相对于蚕豆的竞争力较无间甲酚处理时分别提高24.82%、19.26%和79.30%; 增加供水可弱化间作小麦的相对竞争力, 无间甲酚和间甲酚处理间作小麦的相对竞争力在75%供水水平下较45%供水水平分别降低158.08%和79.67%。     

减量施氮与大豆间作对蔗田土壤温室气体排放的影响

采用静态箱 气相色谱法对常规施氮(N2, 525 kg·hm^-2)y和减量施氮(N1, 300 kg·hm^-2)处理下甘蔗与大豆按行数比1∶1(SB1)和1∶2(SB2)间作、甘蔗单作(MS)、大豆单作(MB)种植模式下蔗田土壤CO₂、N₂O、CH₄排放通量及土地当量比(LER)进行观测和对比分析, 以探讨不同间作模式及施氮水平下甘蔗//大豆间作农田土壤温室气体排放的动态变化规律及对作物产量的影响, 为制定农田温室气体减排措施提供合理的依据。研究结果表明, 减量施氮处理甘蔗//大豆(1∶2)间作模式(SB2-N1)农田土壤CO₂排放总量较甘蔗单作(MS)显著降低35.58%, N₂O累积排放总量较甘蔗单作降低56.36%, CH₄累积排放总量较甘蔗单作升高7.02%; 不同种植模式和施氮处理蔗田土壤均表现为CO₂和N₂O的排放源, CH₄吸收汇, 追施氮肥后土壤对CH₄的吸收速率降低, 但CO₂和N₂O的排放速率增加。MS-N1、SB1-N1、SB2-N1、MS-N2、SB1-N2、SB2-N2和MB处理土壤CO₂年累积排放总量(kg·hm^-2·a^-1)分别为5 096.89、6 422.69、3 283.20、4 103.29、4 475.84、4 775.31和4 780.35, 土壤N₂O年累积排放总量(kg·hm^-2·a^-1)分别为4.61、5.11、2.15、3.13、3.72、5.60和3.11, 土壤CH₄年累积排放总量(kg·hm^-2·a^-1)分别为 13.68、 21.78、 12.72、 5.53、 11.36、 4.77和 9.97。甘蔗//大豆间作系统2009-2012年土地当量比(LER)均大于1, 且减量施氮水平下, 甘蔗//大豆(1∶2)间作模式优势最明显。     

间作苜蓿棉田节肢动物群落结构及时间格局

应用多样性指数、均匀性指数、丰富度、主分量分析方法和最优分割法,研究了不同时期敦煌间作苜蓿棉田节肢动物群落结构及时间格局。结果表明,间作苜蓿棉田节肢动物群落的物种丰富度、多样性和均匀性指数在时间过程中的变化有明显的差异性和规律性。在时间变化过程中,影响节肢动物群落的主导因素和时间格局分化明显,将间作苜蓿棉田节肢动物群落在时间动态中的变化分为5个阶段,并结合气候、物候变化,分析了各阶段内主要害虫和天敌的发生特点。     

Nitrogen fixation efficiency,interspecies N transfer,and root growth in barley-field pea intercrop on a Black Chernozemic soil

Summary Barley-field pea intercrops have been shown to increase N yield when grown under cryoboreal subhumid conditions. In this study, we extended previous research by testing the hypotheses that (1) the intercropped field pea fixes a greater proportion of its shoot and root N than does sole-cropped field pea; (2) N is transferred from the annual legume to the cereal during the growing season; and (3) root production is greater under intercropped than sole-cropped conditions. Unconfined microplots seeded to barley, field peas, or a barley-field pea intercrop were fertilized with N at 10 kg ha^-1 as (NH₄)₂SO₄ (5.21 atom % ¹⁵N excess). Both the intercropped and sole-cropped barley derived more than 93% of their N from the soil. In contrast, 40% of N in the intercropped field pea was derived from soil. This study provided no evidence for transfer of N from the legume to the cereal. On average, the proportion of N derived from air by both pea intercrops was 39% higher than that derived by the sole-cropped pea. Root length determined by a grid intersection method following digitization using an image analyzer tended to be higher under intercropping than in sole crops. We conclude that even on fertile soils benefits may accrue from annual intercropping that includes a legume. The benefits arise from (1) increased N production, (2) greater N-fixation efficiency, and/or (3) more shoot and root residue-N mineralization for subsequent crops.     

梨园套种松阳大红袍赤豆效果研究

研究梨园套种松阳大红袍赤豆的效果,结果表明:松阳大红袍赤豆对土壤具有明显的培肥、保水和降温的效果,改善了土壤理化性状,促进梨树的生长,提高优质果的生产比例。     

基于ISAREG模型的小麦间作玉米灌溉制度设计

将ISAREG模型与种植模式相结合研究小麦间作玉米的灌溉制度。对间作条件下灌溉制度模拟所需的各项参数进行了预处理和验证,分析评价了小麦间作玉米的实际灌溉制度,在此基础上根据小麦间作玉米的需水特性进行了多组合方案设计,分别得到了现状供水状况下和不受灌水日期约束时的优选灌溉制度。     

Soil nitrate dynamics in relation to nitrogen source and landscape position in Malawi

Nitrogen is normally the nutrient most limiting production of maize (Zea mays) — the main staple food crop — in southern Africa. We conducted a field study to determine the effect of N sources on soil nitrate dynamics at three landscape positions in farmers' fields in southern Malawi. The landscape positions were dambo valley or bottomland, dambo margin, and steep slopes. The N sources were calcium ammonium nitrate fertilizer applied at 120 kg N ha^–1, biomass from Sesbania sesban, and no added N. Sesbania biomass was produced in situ in the previous season from sesbania relay cropped with maize. Nitrate in the topsoil (0 to 15 cm depth) increased to 85 days after maize planting (mean = 48 kg N ha^–1) and then decreased markedly. Application of N fertilizer and sesbania biomass increased soil nitrate, and nitrate-N in topsoil correlated positively with amount of incorporated sesbania biomass. The strongest correlation between sesbania biomass added before maize planting and topsoil nitrate was observed at 85 days after maize planting. This suggests that the sesbania biomass (mean N content = 2.3%) mineralized slowly. Inorganic N accumulated in the subsoil at the end of the maize cropping season when N fertilizer and sesbania were applied. This study demonstrated the challenges associated with moderate quality organic N sources produced in smallholder farmer's fields. Soil nitrate levels indicated that N was released by sesbania residues in the first year of incorporation, but relay cropping of sesbania with maize may need to be supplemented with appropriately timed application of N fertilizer.This revised version was published online in November 2005 with corrections to the Cover Date.