Recycling of Chicken and Duck Litter Ash as a Nutrient Source for Japanese Mustard Spinach

ABSTRACT

Recycling combusted poultry litter ash as a soil amendment would potentially ameliorate problems normally associated with poultry waste management. We evaluated the effect of chicken litter ash (CLA) and duck litter ash (DLA) as nutrient sources for Japanese mustard spinach (Brassica rapa L. var. perviridis) grown on a sand dune soil. Chicken and duck litter were ashed at five temperatures: 200, 400, 600, 800, and 900°C and the resulting ash samples were applied at the rate of 100 kg phosphorus (P) ha^?1. Laboratory analysis showed the highest P extraction with citric acid from CLA and DLA obtained at 600°C. Chicken litter ash was richer in P and potassium (K) than DLA but the later contained more calcium (Ca) and magnesium (Mg). The amount of ammonium acetate soluble calcium (Ca), magnesium (Mg), and K recovered increased with increasing temperature except for Ca and Mg at the highest temperatures, 800 and 900°C. Plants grown in pots with the CLA and DLA obtained at 400°C had the highest P concentration, yielding significantly more biomass with dense green leaf color but on average, the DLA amended soil had greater biomass. However, the P level was higher in CLA treated plants than DLA due to the higher available P level (citric acid soluble). Increases in electrical conductivity and pH of the soil were noted after harvest due to litter ash application. Our experiment demonstrated that poultry litter is potential source of P and other nutrients for horticutural crops.     

乌珠穆沁沙地生物基可降解聚乳酸(PLA)沙障防风固沙效益

为了探究PLA沙障对乌珠穆沁沙地沙化治理的效果,以方格状铺设不同规格(方格边长0.5 m×0.5 m, 1 m×1 m, 2 m×2 m和3 m×3 m)PLA沙障,以不同规格沙障影响的风蚀特征为研究对象,裸沙地设置对照(CK),采用美国HOBO便携式风速采集仪观测距地表10,20,50,100,200 cm高度的风速,同时使用自动旋转集沙仪收集近地表0—30 cm高度输沙量,分析了防风效能、固沙效益和风沙流挟沙粒径的变化特征。结果表明：(1) PLA沙障规格小于3 m×3 m时,风速廓线呈“S”型变化趋势;PLA沙障平均的地表粗糙度为0.64 cm, CK的平均粗糙度为0.51 cm,粗糙度提高了25.48%。(2)铺设PLA沙障后输沙量降低了38.72%～75.69%;PLA沙障输沙率随高度呈现良好的指数关系(R²>0.77);1 m×1 m和2 m×2 m沙障的固沙效益高于其他2种规格沙障,3 m×3 m规格的固沙效益最低,基本接近CK。(3)乌珠穆沁沙地风蚀物颗粒大小介于2～500μm,且大部分颗粒为100～250μm的细沙;铺设PLA沙障后,障格内...     

起沙风速的观测方式及其影响因素研究综述

起沙风速作为研究风沙运动规律、解决风沙工程问题的关键指标之一受到广泛关注。学者们根据研究目的及内容的不同总体主要采用两种研究方法:一是利用风速仪在野外进行直接测量;二是在之前学者研究的基础上,利用理论模型,通过计算临界摩擦速度等求得起沙风速。学者们在选择研究方法时会以研究内容作为参考,而起沙风速的影响因素是其中重要的一项。起沙风速受多种因素的影响,通常情况下:①起沙风速随粒径的增大而增大,但含水量变化会使这种现象发生改变;②植被覆盖度越大、植被类型越丰富、组合模式越复杂起沙风速越大;③地表结皮率、砾石覆盖度、地表粗糙度等均会对起沙风速产生影响。     

豫东平原砂土地种植强筋小麦氮肥施用技术

为了在次适宜种植区的砂土地上栽培强筋小麦提高产量并改善品质,采用常规田间试验及统计分析方法并结合品质测定进行研究。结果表明,在豫东平原砂土地上种植强筋小麦,在施用一定量磷钾肥的基础上,施氮75～375 kg/hm2,增产19.7%～63.5%,平均增产47.7%;籽粒蛋白质含量提高0.9～2.5个百分点,平均相对提高15.7%。以300 kg/hm2施氮量增产效应及对籽粒品质和面粉加工品质性状的改善作用最优,该施氮量的氮磷钾配比(N:P2O5:K2O)为2:1:1.2。在施氮总量均为300 kg/hm2的试验条件下,采取"底追均衡供应"(底、追肥量各占50%)、"追肥两次分配"(拔节期追施30%、孕穗期追施20%),即"532"施肥模式,使强筋小麦产量和品质因素更为协调,在豫东砂土区现行生产、生态及技术条件下,可作为种植强筋小麦实现高产优质目标,氮肥合理分配和运筹的主要技术措施。     

Audiogram measurement based on the auditory brainstem response for juvenile Japanese sand lance <Emphasis Type="Italic">Ammodytes personatus</Emphasis>

In this study, the auditory thresholds for juvenile Japanese sand lance Ammodytes personatus were measured based on its auditory brainstem response (ABR). The amplitude of the ABR waveforms to a sound stimulus were larger than that of the electric background noise caused by general brainwaves and myogenic signals after the averaging procedure. Japanese sand lance responded to low frequency sounds between 128 Hz and 512 Hz with a sound pressure level of 115–125 dB. As the test frequency decreased, so did the auditory threshold level, and the level was about 116 dB at 128 Hz and 181 Hz. These results indicate that Japanese sand lance can detect low frequency sound but are less sensitive than other fish species. These high thresholds are probably caused by the lack of a swim bladder.     

Comparison of invertebrate abundance in a seagrass bed and adjacent coral and sand areas at Amitori Bay,Iriomote Island,Japan

ABSTRACT:   To examine whether or not reef-associated seagrass beds harbor abundant food resources for resident and visiting fishes, the invertebrate density and biomass in a seagrass bed were compared with those in adjacent coral and sand areas at Amitori Bay, Iriomote Island, Japan, in June 2002. The vegetation within the bed was dominated by Enhalus acoroides , the coral area comprising primarily Acropora spp. Epifaunal density was greater on the seagrass than on the corals, whereas biomass was greater on the latter. Tanaids, chironomid larvae, errant polychaetes, and gammaridean amphipods were dominant taxa on the seagrass; larger crustaceans, such as crabs and shrimps, being abundant on the corals. The density of infauna was greatest in the seagrass bed, followed by the coral and sand areas, whereas biomass was greatest in the coral area, followed by the seagrass bed and sand area. Each of the three habitats was dominated by harpacticoid copepods and errant polychaetes, although the density of each taxonomic group differed among the habitats. Important food items of seagrass bed fishes, such as harpacticoid copepods, gammaridean amphipods, errant polychaetes, and tanaids, were abundant in the seagrass bed, the density of each being greater than in the other two habitats.     

新型高效过滤器的研究

对过滤器的结构、过滤机理、过滤材料、过滤速度及过滤精度等项目进行了试验研究。对过滤器的有关性能进行了测试。研制的过滤器结构新颖、体积小、快速快滤，过滤与反冲效果好，过滤速度达到80m／h，过滤精度达到杂质污物去除率90％以上。     

中国爬沙虫资源的开发利用现状及物种问题

首次对中国爬沙虫资源化利用的地区和方式、爬沙虫的资源量及研究现状等进行了综述,并在分析以往资料中对爬沙虫的定义和各地对爬沙虫的称谓的基础上,结合民间调查和幼虫分类研究,建议将爬沙虫狭义定义为“广翅目巨齿蛉属和部分大型齿蛉属幼虫的俗称”或广义定义为“广翅目齿蛉科昆虫幼虫的俗称”.对加快爬沙虫的产业化开发提出了几点建议,即加快科研尤其是人工养殖和产品研发力度,保护物种资源,开拓国内外市场.     

乙草胺采用药砂法防除玉米地杂草的效果

[目的]探讨芽前土壤处理除草剂采用药砂法防除玉米地杂草的使用技术。[方法]通过小区试验研究芽前土壤处理除草剂乙草胺采用药砂法防除玉米地杂草的效果。[结果]芽前乙草胺采用药砂法防除玉米地杂草,不仅具有同常规药液喷雾封闭法相同的防除效果,而且还具有工作效率高、使用成本低、对玉米安全、操作劳动强度低等特点,药砂法选用的干燥粗砂直径为0.2~0.3 mm,粗砂使用量以30 kg/hm2为宜。[结论]该技术是适合农村留守老人操作的新技术。     

不同生态区域沙地建群种油蒿的钙组分特征

为探索同一物种在不同生态区域钙组分特征的差异,选择我国北方沙地重要建群种油蒿(Artemisia ordosica)为研究对象,采集了内蒙古杭锦旗、乌审旗、阿拉善左旗以及宁夏盐池县和陕西榆林市榆阳区不同沙地类型、不同生长阶段的油蒿样品,利用连续组分法测定分析了油蒿的钙组分特征.结果表明,在油蒿的不同器官中,叶水溶性钙和醋酸溶性钙均显著高于枝和根,叶与根盐酸溶性钙均显著高于枝.在不同生态区域,降水量较多的地区油蒿体内水溶性钙含量较多,降水量较少的地区油蒿体内盐酸溶性钙含量较高.分析得知,降水条件较好的地区较高的水溶性钙主要体现在油蒿的叶中,而降水条件较差的地区较高的盐酸溶性钙主要体现在油蒿的叶和根中.油蒿在不同生长阶段钙组分没有显著差异,但不同类型沙地上油蒿的钙组分却有显著差异.可见,不同生态区域的油蒿,生境条件越好体内水溶性钙含量越高,生境条件越差体内盐酸溶性钙含量越高.