多措并举保障北京市昌平区设施草莓优质绿色生产

为了保障草莓的安全生产,打造昌平草莓产业的良性健康发展模式,主要从技术支撑、政府扶持及宣传3个方面阐述了其重要举措。具体措施包括通过注重提升田园清理、土壤消毒、田间管理等一系列技术措施,确保草莓安全生产;通过政府政策、资金支持及专业技术指导,打造强有力的后盾保障;建立绿色安全生产宣传模式,扩大品牌影响力,如多渠道、多方面进行宣传;组织培训,增强种植水平;充分利用互联网新媒体等。     

Application of molybdenum fertilizer enhanced quality and production of alfalfa in northern China under non-irrigated conditions

Molybdenum (Mo) is an essential micro-mineral nutrient for plant growth and development. As an important legume forage, alfalfa (Medicago sativa) is frequently planted in marginal lands of northern China where water scarcity and infertile soil are limiting factors for alfalfa production. Mo plays an important role in nitrogen (N) metabolism in general and N fixation in legume species in particular. To evaluate the role of Mo fertilizer in alfalfa quality and production in semi-arid areas of northern China, we conducted a three-year field experiment in Inner Mongolia from 2012 to 2014. Mo fertilizer at the doses of 0, 150 g hm^?2, 300 g hm^?2yr^?1 was applied consecutively across the three years. Application of Mo at 300 g hm^?2yr^?1 significantly increased dry yield of alfalfa in 2014. Crude protein (CP) content of alfalfa without application of Mo exhibited a decline trend from 2012 to 2014. Application of Mo significantly enhanced total CP in 2012 and 2014, and delayed the reduction in total CP across the three years. In contrast to CP, Mo fertilizer had no significant effects on neutral detergent fiber and acid detergent fiber content. In addition, we found that nitrate reductase activity of alfalfa was increased by Mo fertilizer, which may account for the enhanced CP content in alfalfa. These findings highlight that application of Mo fertilizer can be an effective way to improve alfalfa production and quality in semi-arid areas in northern China.     

基于启发式Johnson算法优化BP神经网络的水产养殖产量预测模型

针对水产养殖产量预测难的现状,提出一种基于启发式Johnson算法优化的反向传播神经网络(BPNN)的产量预测模型。该模型在传统BP神经网络的基础上,针对网络训练时间长、易陷入局部最优的问题,通过启发式Johnson算法降低输入神经元维度,再结合试凑法确定神经网络隐层个数,构建启发式Johnson反向传播神经网络(HJA-BPNN)学习预测模型。实验结果表明,该模型在山东省对虾海水养殖产量预测中,预测的均方根误差小于传统BP神经网络和GM(1,1),且学习效率相比传统BP神经网络有所提升。研究表明,该学习预测模型在大量历史数据的模型构造上有更大的优势,能够缩短建模时间,同时获得良好的预测效果,为水产养殖产量预测提供了一种可行的新方法。     

Conservation needs for the endangered New Zealand sea lion,Phocarctos hookeri

1. Understanding population size and trend is critical information in species management and conservation. To enable accurate population trend estimates, consistent robust monitoring of a species is essential, particularly for a species such as the New Zealand (NZ) sea lion, Phocarctos hookeri , which has experienced an almost continuous decline in pup production since the late 1990s.
2. This research examines the pup production estimates for all known breeding sites for this species, and using a stage‐structured matrix population model, estimates population size and trend between 1995 and 2015.
3. Overall, it is estimated that 2,316 pups were born in 2015, a decrease of 13% since 1995 and a 27% decline since the highest pup production estimate in 1998. This decline has been driven by the significant decline of 48% at the main breeding area, the Auckland Islands since 1998.
4. Using the stage‐structured matrix population model a total species population size of 11,767 sea lions (95% CrI: 10,790–12,923) was estimated. This is the lowest population size of any sea lion species. Trend data for the Auckland Islands indicated that pup and population numbers have decreased at 1.9% yr^?1 in the last 20 yr, while total species population decline is 0.6% yr^?1.
5. Estimates of population trends for this species have been hindered by inconsistent monitoring at most breeding sites. This study strengthens the growing field of research highlighting the need for consistent long‐term monitoring for the conservation management of endangered species.

     

韩国稻作技术创新与转型

随着社会经济的发展及农业劳动力的转移,韩国水稻种植方式发生了转型。从上世纪70年代末期开始,韩国水稻机插秧比例快速上升,手插秧比例下降,到90年代基本实现了水稻种植的机械化;省工节本的直播稻产量受不确定因素影响较大,且稻米品质不如机插秧和手插秧,其种植面积出现了波动,现只占韩国水稻种植面积的4%左右。本文介绍了韩国水稻机插秧、湿润直播和旱直播技术的作业流程。     

青海八里桥绿萝卜品种提纯复壮技术

为解决八里桥绿萝卜由于长期种植导致部分地区品种退化的问题,通过长期的生产实践,采用原种提纯复壮、良种生产、栽培管理等综合技术,实现了品种的提纯复壮,对维持青海八里桥绿萝卜品种的特殊品质具有重要意义。     

鄂尔多斯市主要农业气象灾害及气象服务措施

结合鄂尔多斯市农业生产实际,重点分析了主要气象灾害及其对农业生产的影响,并提出了气象服务措施,以增强农作物产量和品质,提升农民收入水平。     

有机肥对酿酒葡萄土壤微生物、酶活性及产量的影响

为明确施用不同有机肥对土壤有机质、酶活性和微生物以及酿酒葡萄产量的影响,采用田间小区设计,以5 a生赤霞珠酿酒葡萄为试验材料,研究不同有机肥对土层0～20、20～40 cm和40～60 cm中土壤有机质、酶活性和微生物的影响。以不施用有机肥为对照(CK),设置沼渣(BR)、羊粪有机肥(SMOF)、牛粪有机肥(CMOF)、猪粪有机肥(PMOF)、牛粪+沼渣有机肥(CMOF+BR)5个处理进行大田试验。结果表明:不同有机肥施用后与CK相比,土壤有机质增加6.79%～44.97%,土壤微生物碳增加19.78%～91.53%,微生物氮增加2.22倍～3.93倍,碱性磷酸酶增加57.78%～512.55%,过氧化氢酶增加53.45%～240.48%,增产15.12%～46.89%。不同土层施用牛粪有机肥相对于其它有机肥处理土壤有机质含量增长8.49%～33.29%;土壤中微生物碳、氮的含量分别增加5.30%～42.46%和6.12%～49.65%;碱性磷酸酶增大8.01%～184.63%,过氧化氢酶增加5.14%～84.27%,脲酶提高25.58%～410.70%,蔗糖酶升高6.00%～107.65%;微生物总数增多5.99%～56.56%。施用牛粪有机肥相比较其它有机肥增产7.08%～27.60%。说明在宁夏地区施用有机肥可有效提高土壤有机质的含量,增加微生物的数量,增加土壤酶活性,促进酿酒葡萄的生长发育,提高产量,其中以牛粪效果最为显著。     

河套灌区盐渍化土壤玉米水氮耦合效应

为了探求适用于盐渍化地区的节水、施肥优化模式，采用大田试验，以玉米为研究对象，选取了轻度和中度两种盐分土壤，设置了10种不同水、氮处理，建立不同盐分土壤玉米产量与灌水量及施氮量之间的回归模型并对其进行了分析，研究不同盐分土壤水、氮用量对玉米产量的影响。结果表明：在轻度和中度盐分土壤条件下，灌水和施氮对玉米均有增产效应，水、氮交互作用为正效应，水分的作用大于施氮的作用。通过边际效应分析可知，轻度和中度盐分土壤施氮肥的增产速率没有明显差异，轻度盐分土壤灌水的增产效率明显高于中度盐分土壤。轻度和中度盐分土壤玉米最高产量分别为13 581 kg·hm^-2和11 115 kg·hm^-2，对应的水、氮配比均为灌水编码为0.77（全生育期灌水量2 250 m³·hm^-2），施氮编码为0.69（总施氮量225 kg·hm^-2）。通过模型寻优，得到轻度和中度盐分土壤种植玉米的最佳水、氮配比方案均为全生育期灌水量为1 900.95~2 389.08m³·hm^-2，总施氮量为174.04~240.7 kg·hm^-2。优化方案的水、氮用量分别比当地灌水量（2 925 m³·hm^-2）节水18.2%~35%, 施氮量（325 kg·hm^-2）节肥26.0%~46.4%。优化范围包含了轻度和中度盐分的最高产量水、氮用量，产量与当地产量基本一致，符合当地灌水施肥要求。但从维持目前玉米产量和长期盐碱地改良的角度看，建议中度盐化土壤应选取水、氮优化范围中中等偏上灌水量和中等偏下的施肥量，以便于从根本上降低土壤盐分背景值，便于长期产量的提高；轻度盐分土壤选取优化范围适中的水、氮用量。     

Effect of transferring lignocellulose-degrading bacteria from termite to rumen fluid of sheep on in vitro gas production,fermentation parameters,microbial populations and enzyme activity

The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.