Performance of Fatty Liver Development in Response to Brown Rice and Corn-Based Diets in Overfed Landes Geese(Anser anser)

The effect of brown rice and corn-based diets on fatty liver weight, carcass traits, lipids accumulation and liver composition of Landes geese (Anser anser) after feeding the same amount of each diet was investigated. After 2 weeks overfeeding, besides body weight and body weight gain increased significantly, the fatty liver weights were increased dramatically from 94.67 to 554.67 and 754.00 g in corn treatment and rice treatment, respectively, and the accumulation lipids in adipose tissues reached up to or close to 2 folds of initial weight in both treatments. Liver weight was greater in brown rice group than in corn group (P<0.05). Compared to before overfeeding, triacylglycerols (TG) in geese fatty liver increased dramatically and predominated (from 9.08% to close to or more than 90% of hepatic lipids), whereas phospholipids (PL) and cholesteryl esters (CE) decreased sharply in both treatments (P<0.05). However, the percentages of lipids, TG and PL in fatty liver were higher in brown rice treatment than in corn treatment, and that of CE was lower (P<0.05). It indicates that overfeeding chiefly results in lipids accumulation in goose fatty liver and adipose tissues. Brown rice-based diet induces greater fatty liver, and brown rice is one of high quality overfeeding ingredients instead of corn.

湖南耕地土壤和稻米重金属污染防控实践与思考

湖南省是我国主要产粮区之一。由于矿产经济活动及其他人类活动,大面积耕地土壤受到重金属污染,从而一些地方的稻米重金属含量超过国家食品卫生标准。本研究对湖南省耕地土壤与稻米重金属污染现状和成因进行剖析。结果表明:湖南耕地土壤重金属污染特征是复合污染为主,污染程度逐年上升,主要分布在湘江流域和工矿区,并逐渐蔓延至养殖区,稻米重金属污染主要以Cd为主,其次是As和Pb。针对湖南稻米重金属污染的各种防控措施,阐述其工作原理、应用实例和优缺点,然后对湖南省开展的土壤重金属污染修复措施和研究进行总结与思考,提出应当构建一种基于土壤组成的原味钝化材料耦合易操作农艺措施的经济、绿色、高效的综合性技术方案,以期来修复耕地土壤重金属污染和降低稻米重金属含量,保障粮食安全生产。

Suitable Land Assessment for Rice Crop in Burkina Faso Using GIS, Remote Sensing and Multi Criteria Analysis

In Burkina Faso, rice consumption is currently common and increasing in both, rural and urban areas. Although several efforts have been made by the state to develop land for rice cultivation, the population’s demand is still greater than the supply. Nevertheless, the country has great potential for rice cultivation. This study aims to analyze the suitability of land for rice cropping in the province of Nahouri. Field and satellite data were collected to map the rice crops developed areas. Furthermore, morphopedological, topographic, land use/cover, and accessibility to land data were collected and integrated into a Geographic Information System (GIS) based on simple Multi-Criteria Analysis (MCA). Land suitability for rice crop was performed. The results show that the total suitable area for rice cultivation in the province is 106,373 ha (28% of the province) where the most suitable areas cover 32,614 ha and the suitable areas cover 73,759 ha. Already 3144 ha of the province area had been developed for rice cultivation with 815 ha and 845 ha of most suitable and suitable areas respectively whereas more than 45% of the developed lands were not fit for the rice crop suitable land.

耕地经营规模对农户水稻生产生态效率的影响——以常德市为例

提高水稻生产生态效率是协同实现保障粮食产量稳增长与减少粮食生产环境损耗双目标的关键路径,耕地作为农业生产活动最基本的生产资料之一,探索耕地经营规模对农户水稻生产生态效率的影响对促进农业适度规模化经营和耕地可持续利用具有重要意义。本文基于粮食生产微观主体——农户的视角,从理论上揭示耕地经营规模对农户水稻生产生态效率的影响,并利用常德市416份农户问卷调查数据,运用随机前沿分析法构建效率测算模型和影响模型进行实证检验。研究表明:农户耕地规模化水平和水稻生产生态效率均有待提升,样本农户中较小规模农户数量最多,占总样本的94.95%,较小规模农户仍是农业生产的主力;农户水稻生产生态效率均值为0.830,还存在0.170的提升空间。耕地经营规模对农户水稻生产生态效率有显著影响,二者并非简单线性关系而是呈“倒U型”关系,且拐点所在区间为1.2~1.4 hm2;农户水稻生产生态效率还受到户主受教育程度、抚养比、农业收入占比的显著正向影响和户主年龄的显著负向影响。因此,应在尊重较小规模农户将长期存在这一现实的基础上,进一步推进耕地适度规模经营并培育新型农户,以促进水稻生产生态效率提高。

盐碱胁迫水稻根系研究

我国盐碱地面积约为1×108 hm2,其中可利用的盐碱地约0.37×108 hm2,盐碱地是重要的耕地后备资源,开发利用潜力巨大。开发种稻是盐碱地改良和利用的有效措施,水稻根系研究对挖掘盐碱水田增产潜力具有重要意义。本文概述了国内外盐碱胁迫水稻根系的研究现状,重点从盐碱胁迫对水稻根系表型、抗逆生理及产量形成的影响等方面的研究进展进行了综述,并对该研究领域未来发展进行了展望。以期多角度全面解析盐碱胁迫水稻根系逆境形态和生理机理,明确土壤-根系-产量的互作机制,基于优良种质资源结合育种技术构建理想根系构型,为挖掘盐碱地水稻增产潜力提供参考。

我国主要粮食产区土壤有效态钙镁硫的变化特征及其对作物产量的影响

中量元素钙、镁、硫对农业生产的作用日益突出,研究土壤有效态钙镁硫的变化特征及其对作物产量的影响,可为全国和区域尺度耕地土壤中量元素管理和合理施肥提供理论依据。基于覆盖全国697个耕地质量监测点的监测数据,对比分析2016和2021年全国及六大粮食产区(东北区、华北区、西北区、西南区、长江流域和华南区)的土壤有效态钙镁硫含量的变化特征及其对主要粮食作物产量的影响。与2016年相比,2021年697个监测点的土壤交换性钙和交换性镁平均含量变化不显著,有效硫平均含量显著下降了27.3%,全国交换性钙、交换性镁和有效硫主要与土壤pH和有机质(OM)相关。六大粮食产区土壤有效态钙镁硫含量的年际变化特征有所不同。与2016年相比,2021年东北区交换性钙和镁含量分别显著增加了25.5%和52.4%,主要与pH相关;有效硫含量显著下降了47.8%,主要与速效钾相关。华北区交换性钙含量显著下降了11.8%,主要与pH相关。西北区交换性钙、镁和有效硫含量分别显著下降了64.0%、54.0%和30.4%,钙主要与总钾相关,镁主要与全磷相关,硫与土壤其他理化性质不存在显著相关。西南区有效硫含量显著下降了30.0%,主要与pH和OM相关。长江流域交换性镁和有效硫含量分别显著下降了52.0%和15.7%,主要与pH和OM相关。华南区3种有效态中量元素含量变化不显著,三者主要与pH和OM相关。在全国尺度下,水稻产量与土壤交换性钙和镁含量呈显著正相关,玉米产量与交换性镁和有效硫含量呈显著正相关,小麦产量则与3种中量元素不存在显著相关性;当pH≤7.0时,小麦产量与交换性钙和镁含量呈显著正相关,当pH>7.0时则不存在显著相关性;无论土壤呈酸性还是碱性,小麦产量均与有效硫含量不存在显著相关性。综上,2016—2021年的5年间,我国耕地土壤交换性钙、镁含量变化不显著,有效硫含量显著降低,这些中量元素主要与土壤pH和OM相关。六大粮食产区中量元素含量变化特征和影响因素及其对主要粮食作物产量的影响存在较大差异,针对性施用中量元素肥料有助于提升区域粮食产量。

寒地水稻增氧浸种催芽方法试验研究

浸种催芽是种植水稻过程中决定性的一环,其要素是水、气、热条件。现在的寒区水稻浸种催芽过程中,农户仅对水、热条件进行经验性控制,智能化程度低,劳动强度大,且浸种效果相对较差。采用正交设计方法试验分析了温度、曝气间隔、浸种时长的耦合试验,得到这3个因素对水稻种子发芽率、芽长及其均匀度的影响程度从大到小依次为曝气间隔、浸种时长、温度,且理想的一组因素水平为浸种温度30℃、曝气间隔1h、浸种时间46h。

江苏省滨海盐碱地籼粳杂交稻产量优势形成特征

旨在探明滨海盐碱地大田条件下籼粳杂交稻产量优势形成特征。2021—2022年,在江苏省滨海盐碱地择取中度盐碱地(medium saline-alkali soil,MS,土壤电导率平均2.7 dSm^(-1))和重度盐碱地(high saline-alkali soil,HS,土壤电导率平均7.2 dSm^(-1))两类典型田块,以籼粳杂交稻(甬优2640和甬优4949)、常规粳稻(南粳9108和淮稻5号)、杂交籼稻(丰优香占和Y两优372)3种类型水稻品种为试材,探究实地条件下盐胁迫对不同类型品种产量及其形成特征的影响。与中度盐碱地相比:(1)重度盐碱地下各类型品种的穗数、每穗粒数、结实率和千粒重均显著低于中度盐碱地。中度和重度盐碱地下,籼粳杂交稻的产量均显著高于常规粳稻和杂交籼稻,这主要是由于其较高的每穗粒数。(2)重度盐碱地下各类型品种关键生育期(拔节、抽穗和成熟期)的群体茎蘖数及茎蘖成穗率均显著下降。中度和重度盐碱地下,常规粳稻和杂交籼稻关键生育期的群体茎蘖数及茎蘖成穗率均高于籼粳杂交稻。(3)重度盐碱地下各类型品种关键生育期的干物重均显著下降。中度及重度盐碱地下,籼粳杂交稻抽穗期和成熟期干物重、拔节期—抽穗期和抽穗—成熟期作物生长速率均显著高于常规粳稻和杂交籼稻。重度盐碱地下各类型品种的收获指数呈上升趋势。籼粳杂交稻在重度盐碱地下的收获指数高于常规粳稻和杂交籼稻。(4)重度盐碱地下各类型品种关键生育期的叶面积指数、播种期—拔节期、拔节期—抽穗期和抽穗期—成熟期光合势均显著下降。中度和重度盐碱地下,籼粳杂交稻成熟期叶面积指数和抽穗期—成熟期光合势均显著高于常规粳稻和杂交籼稻,抽穗期—成熟期叶面积指数衰减率则呈相反趋势。(5)重度盐碱地下各类型品种株高、上三叶叶长和叶宽、叶片SPAD值和光合速率均显著下降。中度和重度盐碱地下,籼粳杂交稻上三叶叶长和叶宽、叶片SPAD值和光合速率均高于常规粳稻和杂交籼稻。本研究结果表明,滨海盐碱地实地条件下,盐胁迫显著影响水稻产量及其形成特征。与常规粳稻和杂交籼稻相比,籼粳杂交稻在滨海盐碱地仍具有较高的产量优势,这主要得益于其较高的每穗粒数;此外,较高的作物生长速率、较大的上三叶叶面积及其较强的叶片持绿性也是籼粳杂交稻在滨海盐碱地具有较好产量优势的重要特征。

发酵农林废弃物对镉污染耕地安全利用效果及持效性研究

为探讨以针叶类树皮为主的农林废弃物发酵后对镉污染耕地大米中镉含量的影响,通过耕地修复实验室小试、盆栽及大田试验,系统研究FBA(修复材料)对耕地镉污染土壤的钝化效果,考察修复材料对作物生长情况、农作物产量、作物中镉吸收、土壤中镉有效态含量和土壤中其他理化指标的影响。研究表明:①FBA对水溶液中镉的去除率均在93.3%以上;②添加1%FBA能够促进了农作物分蘖发生;③添加1%FBA土壤中全氮增加30.85%,有机质增加26.61%,有效提高了土壤的肥力;④添加1%FBA的处理组当季稻米中的镉含量均低于0.2 mg/kg。通过研究结果可知,FBA无生物毒性,对种子发芽率、根伸长均有促进作用,不仅能够有效降低稻米中的镉含量,添加材料后的当季水稻镉含量即刻达标,同时修复效果保持稳定,而且具有一定的肥效作用。

Soil Resources and Land Use in Tropical Asia

Tropical Asia is a region comprising South and Southeast Asia and under strong influence of the Asianmonsoon climate. It is characterized by an extremely high population density and by high land use intensity.Paddy rice cultivation is the most important form of agriculture in the greater part of the region. Soilresources of tropical Asia have a specific feature in comparison with tropical Africa and America. Ultisolsdominate in uplands, and lowland soils like Inceptisols and Histosols are relatively abundant. The latterpoint is made clearer if we take the landforms of the region with a vast extent of lowlands into consideration.Geologically, tropical Asia with the Himalayan orogeny and active volcanism exhibits a conspicuous contrastto tropical Africa and America with the dominance of the shield structure. This along with the monsoonclimate should have determined the basic features of landforms and soil, and accordingly all the agriculturaland social characteristics of tropical Asia today. Although paddy rice cultivation in the lowland is highlysustainable, upland cultivation in extensive Ultisol areas tends to be handicapped by low fertility and higherodibility of the soil, resulting in low sustainability. Land shortage is compelling people to exploit slopelandsin hills and mountains, on the one hand, and thus far unutilized coastal lowlands, on the other. Both ofthese new reclamations are facing to serious land degradation problems today. Tropical Asia will continueto be the most densely populated region of the world with ever-increasing population. In order to meet theincreasing food demand lowland rice cultivation should be intensified by the infrastructure development toease the stresses on slopelands and vulnerable coastal lowlands. At the same time, upland crop productionin Ultisol areas should be stabilized and enhanced, providing integrated nutrient management and measuresfor soil conservation.

Land-use induced changes in topsoil organic carbon stock of paddy fields using MODIS and TM/ETM analysis:A case study of Wujiang County,China

Topsoil soil organic carbon (SOC) that plays an important role in mitigating atmospheric carbon dioxide (CO_2) buildup is greatly affected by human activities.To evaluate the influence of land-use changes on SOC stocks in paddy soils,a new algorithm was developed by integrating MODIS (moderate resolution imaging spectral-radiometer) and TM/ETM data for timely monitoring the land-use change in Wujiang County.Thereafter,the land-use class-maps derived from MODIS and TM/ETM analyses were further used to estima...

Do Land Characteristics Affect Farmers' Soil Fertility Management?

Soil fertility management （SFM） has important implications for sustaining agricultural development and food self-sufifciency. Better understanding the determinants of farmers’ SFM can be a great help to the adoption of effective SFM practices. Based on a dataset of 315 plots collected from a typical rice growing area of South China, this study applied statistical method and econometric models to examine the impacts of land characteristics on farmers’ SFM practices at plot scale. Main results showed that in general land characteristics affected SFM behaviors. Securer land tenure arrangements facilitated effective practices of SFM through more diversiifed and more soil-friendly cropping pattern choices. Plot size signiifcantly reduced the intensities of phosphorus and potassium fertilizer application. Given other factors, 1 ha increase in plot size might reduce 3.0 kg ha-1 P2O5 and 1.8 kg ha-1 K2O. Plots far from the homestead were paid less attention in terms of both chemical fertilizers and manure applications. Besides, plots with better quality were put more efforts on management by applying more nitrogen and manure, and by planting green manure crops. Signiifcant differences existed in SFM practices between the surveyed villages with different socio-economic conditions. The ifndings are expected to provide important references to the policy-making incentive for improving soil quality and crop productivity.

吉林省西部盐碱地水稻直播现状、存在问题及发展建议

介绍了吉林省西部地区的土壤、气候特点及水稻直播现状,对直播水稻品种、配套栽培技术、理论指导与实际操作的协调性等方面存在的问题进行了初步分析,并对今后该区域水稻直播的发展提出针对性建议。

从嘉禾到杂草:东北地区的稗子种植与低湿地开发

稗在中国主流农业历史叙事中多为稻田伴生杂草或灾荒年份的救荒作物,但在传统时期的东北地区却是一种主粮作物,地位不次于“五谷”,耐寒、耐湿的抗逆性特征使其成为东北地区历史上低湿地开发的主力。当地农民在长期栽培实践中,培育出一批高产、抗涝性状好的品种,形成了一整套颇具特色的种植技术。近代以来,随着东北地区农田水利兴起、抗寒性水稻品种次第引入,先前植稗的沮洳之地被整治为水田,优质高产的水稻成为低湿地开发的主角。稗子作为一种谷物逐渐淡出人们的视野,沦为一种饲料作物。某种程度上说,稗子退却的历史,即近代以来东北亚中高纬度地区低地开发与农业发展的缩影。

基于Longley-Rice模型的着陆场通信覆盖性能仿真分析研究

本文在Longley-Rice模型基础上,通过分析构建有效模型,选择相关系统参数和环境参数,对着陆场三种典型架设基站环境进行仿真,并与实测结果进行比较分析,该模型可以很好预测信号衰减,可以作为系统方案设计技术依据。

鄂北岗地水稻病虫害绿色防控技术研究

鄂北岗地水稻全生育期病虫害较严重,为有效防控水稻病虫害,切实提高粮食产量和品质,选取农业生态防控、理化诱控和生物防控三种绿色技术及其防效进行研究,提出了绿色防控技术集成的有效实施路径。

华南区稻田耕地质量空间分布与产能提升潜力

为了明确华南区稻田耕地质量空间分布及其提升潜力,为实现华南区水稻高产稳产提供科学依据,本研究基于2017年农业农村部耕地质量监测保护中心在华南区开展的耕地质量区域汇总评价数据,分析华南区稻田耕地质量空间分布情况及其与产能对应关系,并利用随机森林模型明确影响产能提升的主要限制因子。华南区稻田耕地质量等级呈现“中间高,四周低”的空间分布规律;利用半方差函数拟合结果表明,华南区稻田耕地质量等级呈中度空间相关性(R2=0.95),以广东(3.82)最高,海南(5.32)最低。华南区耕地质量评价指标中,土壤养分指标空间分布差异较大,土壤全氮和缓效钾含量空间分布呈强烈的空间相关性,分别呈现“西高东低”和“北高南低”空间分布规律;土壤有机质、有效磷、速效钾含量呈中度空间分布相关性,分别呈现由西向东、由东向西、由北向南不断降低的空间分布趋势;土壤pH整体呈弱酸性(5.40)。土壤物理性状、立地条件、土壤管理情况及土壤健康状况以东部较好,西部较差。华南区稻田耕地质量等级与单产整体呈显著正相关性(R2=0.9140),水稻产量随耕地质量等级提升呈先迅速增加后趋于平缓趋势;华南区稻田耕地质量等级与水稻产量可持续指数呈显著正相关(R^(2)=0.9333)。随机森林模型的重要性分析结果表明,土壤有效磷含量、灌溉能力和土壤有机质含量是影响华南区水稻产量的最关键因素。情景模拟表明,若华南区稻田耕地质量等级分别提升0.5、1.0、1.5个等级,则水稻将增产14.93%、22.39%、29.86%,相当于节约耕地面积31.77万hm^(2)、56.35万hm^(2)、75.95万hm^(2)。华南区稻田耕地质量和产能仍有较大提升潜力,通过提升耕地质量来提升产能对保障粮食安全、促进农业绿色生产具有重大意义。