太湖流域典型地区农田土壤有机碳变化状况研究

以太湖流域某一典型区为例,研究了上世纪50年代至本世纪初农田土壤有机碳变化状况.研究结果表明,上世纪50年代至上世纪80年代初,由于大量施用化肥、有机肥用量急剧减少等原因,农田土壤有机碳含量显著降低;上世纪80年代初至2004年,由于大量粮食作物转变为蔬菜等经济作物的种植,而蔬菜等经济作物有机肥施用量较大,导致典型区农田土壤有机碳基本保持稳定甚至略有增加.肥料施用策略的变化以及种植制度的改变是导致太湖流域典型区农田土壤有机碳发生变化的主要原因.     

云南省化肥施用现状及减量增效的途径研究

针对云南省化肥用量偏高、施肥结构不合理、肥料利用率较低、施肥方式落后,且化肥施用量逐年增长的问题。收集了全省《测土配方施肥农户施肥情况调查表》信息410095份,统计了全省16个州市的351194块地块410095季作物的施肥情况,综述了过量施用化肥的危害。建议采取适类、适时、适量、科学的施肥方法和技术,科学的田间管理,“化肥 ”三方面的措施,实现我省化肥零增长的目标。为农业生产提供指导,以保证我省粮食安全。     

Effect of Oil Palm Fly Ash on Soil Properties and Yield of Sweet Corn in the Tropical Zone of Thailand

Disposal of oil palm fly ash (OPFA) into the environment causes environmental pollution. A field experiment was conducted to evaluate the effects of OPFA and mineral fertilizer on soil properties and yield of sweet corn. A total of six treatments were applied that included 2, 4, and 6 t ha^–1 OPFA, 200 kg ha^–1 nitrogen, phosphorus, and potassium (NPK), 100 kg ha^–1 NPK + 2 t ha^–1 OPFA as well as the control. A significant increase in soil pH and available P was observed with the sole OPFA treatments at 2, 4, and 6 t ha^–1, while a significant increase in exchangeable cations [K, magnesium (Mg)] was detected only at the 6-t ha^–1 OPFA treatment. The highest grain yield of 4220 kg ha^–1 was obtained at the 100-kg ha^–1 NPK + 2 t ha^–1 OPFA-treated plots, which was statistically similar with the grain yield of 3800 kg ha^–1 received at the 200-kg ha^–1 NPK-treated plots. The practical implication of this study is that OPFA can be used as a liming material to increase soil pH and it has a synergetic effect in combination with inorganic fertilizer.     

Response of soil multifractal characteristics and erodibility to 15-year fertilization on cropland in the Loess Plateau,China

Understanding the influence of long-term fertilization on the multifractal characteristics and erodibility of soil of cultivated land on the Loess Plateau of China could help prevent soil erosion and promote the sustainable development of agriculture. We collected 27 soil samples from 0 to20 cm layers of nine fertilizer treatments. Rényi spectrum (D_q) and singularity spectrum (?(α)) were applied to characterize soil particle-size distribution (PSD). The multifractal parameters of capacity dimension (D₀), entropy dimension (D₁), Hölder exponent of order zero (α₀), and erodibility K and anti-erodibility indices (aggregate state and degree) were used to determine the effect of fertilization on soil properties and erodibility. The multifractal models could characterize the PSDs in the various fertilizer treatments well. Treatments receiving manure had higher D₀, D₁, α₀, soil organic carbon (SOC) content, aggregate state and degree and lower erodibility. It was concluded that D₀, D₁, and α₀ could clearly discriminate among the various treatments, and the combined application of mineral fertilizers and organic manure greatly improved soil quality and structure of the cultivated land in the Loess Plateau. Furthermore, changes of multifractal parameters D₀, D₁, and α₀, especially D₁, was mainly due to the reduced soil erosion and the increase of SOC.     

工商资本下乡对农地流转及利用的影响分析——基于南京市锁石村的调研实证

基于南京市锁石村的调研,运用对比分析法、极大化法、极小化法、熵值法,通过对暂无与存在工商资本下乡地区的对比,探究工商资本下乡对农地流转及利用(包含经济效益、生态效益)的影响。结果表明,工商资本下乡会促使农地加速流转,而农地的大面积流转会吸引工商资本;工商资本下乡在带来经济效益的同时,农药化肥的过量使用可能会导致土壤质量下降。工商资本在考虑经济收益同时应约束农药、化肥的用量,以促进农地的可持续利用。     

绿色富硒不知火高产优质栽培与管理

阐述了绿色富硒不知火的品质优势和价格优势,并根据不知火的生态特性和生长习性,从园地选择、土壤改良、开垦定植、整形修剪、肥水管理、杂草管理、病虫害防治、结果期管理整个栽培流程8个方面进行了详细的阐述,以期通过严格科学的管理技术获得高产优质的富硒绿色不知火产品。     

粤优938在缅甸的高效栽培技术研究

[目的]研究粤优938在缅甸的高效栽培技术。[方法]对粤优938进行不同密度的栽插试验与肥料用量和运筹试验。[结果]粤优938在缅甸生育期明显缩短,为保证产量,以每穴栽插4苗带蘖壮秧,栽插密度控制在20万穴/hm~2为宜;采用复合肥80%为基肥、20%为分蘖肥+尿素80%为分蘖肥、20%为促花肥的肥料运筹方法,基肥于插秧前施用,分蘖肥于插秧后4、10 d分2次均匀施用,促花肥在叶龄余数3左右时施用为好。[结论]根据缅甸稻谷收购价格低而肥料成本高的实际,在缅甸进行粤优938高效栽培时,肥料施用量以复合肥+尿素商品用量300 kg+450 kg/hm~2为好。     

河北省昌黎县赤霞珠葡萄产区土壤养分及施肥状况分析

试验采用实地调查和土壤测定的方法,研究了河北省昌黎县赤霞珠葡萄产区土壤养分和施肥状况。结果表明,在施足氮肥和磷肥的基础上,加大有机肥和钾肥的投入对提高酿酒葡萄的产量和品质作用较大;各调查点土壤养分含量之间的差异与施肥量和土壤质地有关。     

肥料增效剂对夏玉米植物学性状、产量构成及土壤中NH4+-N和NO3--N的动态影响

2014、2015年夏季,试验采用单因素随机区组设计,以先玉335为材料,设置两种肥料增效剂、7种施肥方式,研究大喇叭口期和抽雄期植物学性状、施肥后0、14、28、42 d时0~30 cm和31~60 cm土壤中NH_4~+-N和NO_3~--N含量以及收获时玉米穗部性状和产量差异。结果表明,分期施肥比全部氮肥作底肥更能促进夏玉米茎粗、叶面积、气生根数量、穗长、穗行数和行粒数等增加。与对照和不施用肥料增效剂相比,0~30 cm和31~60 cm土层中施用两种肥料增效剂的NH_4~+-N含量较高,NO_3~--N含量较低,控制了NH_4~+/NO_3~-比例。两种肥料增效剂相比,Entrench效果明显优于NMAX。     

减量施肥对越夏番茄产量、品质及土壤养分的影响

为研究减量施肥对大棚越夏番茄栽培的影响,采用田间试验,研究常规施肥(CK)和3个减量施肥处理(T1、T2和T3)对番茄产量、营养品质和土壤养分的影响。3个减肥处理分别为:降低CK磷肥用量50%的处理T1、降低T1处理肥料用量20%和50%的处理T2和T3。结果表明,减肥处理番茄单果质量、产量和养分携出量与CK差异不显著。与CK相比,减肥处理均显著提高番茄根冠比、2mm根数、番茄果实还原性糖质量分数和糖酸比,增幅分别为23.8%～27.0%、35.7%～103.6%、9.3%~16.5%和16.4%～25.8%。减肥处理尤其T3处理显著降低收获后表层土壤NO-3-N、速效磷、0～40cm土层土壤速效钾累积量及表层土壤电导率的增幅。因此,在当前农民常规氮磷钾肥施用量下,减少氮磷钾用量不会导致番茄减产,反而具有改善果实品质和土壤养分过量累积的效果。其中在本试验条件下N-P_2O_5-K_2O用量为424.8-222.8-607.3kg/hm~2时,番茄品质和土壤养分累积情况最佳。