Soil property differences among high‐ and average‐yielding soya bean areas in Arkansas,USA

Soya bean [Glycine max (L.) Merr] yields >6719 kg/ha (100 bu/ac) have only recently and infrequently been achieved. Quantifying soil property differences between high‐ and average‐yielding areas can help to further identify non‐plant‐related properties contributing to soya bean yield potential. The objective of this study was to evaluate the effects of region and soil depth on soil property differences between high‐ and average‐yielding areas. In each of the seven regions of the ‘Grow for the Green’ yield contest in Arkansas, prior to or just after harvest in 2014 and 2015, soil samples were collected from the top 20 cm of one contest high‐yield (HY ) area that was in close proximity to an average‐yield (AY ) area. Across all regions and both years, soya bean yields differed (P  <  0.05) between yield areas, averaging 4701 and 5498 kg/ha in AY and HY areas, respectively. Averaged across soil depth and years, numerous soil properties differed (P  <  0.05) between HY and AY areas within at least one of seven regions. Total soil C content was at least 20.2% greater in the HY than in the AY area in three of seven regions. Extractable soil P content was, on average, 19.4 kg/ha greater in HY than in AY areas in three of the seven regions. Results from this study have the potential to help producers better understand soil properties that contribute to or hinder achieving ultra‐high (>6719 kg/ha) soya bean yields.     

杭州余杭闲林村集体经济发展现状与对策

浙江省自2021年推进共同富裕示范区建设以来,一直将农村经济的高质量发展作为重点发力方向之一。租赁型城中村作为城市快速发展过程中形成的一种特殊经济体,如何摆脱低质量发展、破解转型升级瓶颈是一项重要课题。本文在给出农村分类和国内城中村发展概况基础上,以杭州市余杭区闲林街道的闲林村为案例,解读其发展现状、剖析其面临的困境和难点,并结合其发展阶段和资源禀赋,据此提出拓展产业合作、盘活闲置资金、优化村企治理与考核等推进租赁型城中村集体经济高质量发展的对策建议。     

凤庆茶叶种植与混林茶园生态系统研究

中国云南是世界茶树的原产地,而云南省凤庆县又是滇红的诞生地,具有悠久的茶树栽培种植历史,其混林茶园生态系统也具有较高的研究价值。本文通过对其茶叶种植史和混林茶园生态系统进行梳理和研究,厘清凤庆县茶叶种植的历史发展脉络,挖掘凤庆混林茶园生态系统的优势及其应用价值。     

Effects of Rice Variety and Growth Location in Cambodia on Grain Composition and Starch Structure简

The effects of variety and growth location on grain composition and starch structures were investigated using three rice (Oryza sativa L.) cultivars (Phka Romduol, Sen Pidao and IR66) with different amylose contents. All the three cultivars were planted in three different agro-climatic zones (Phnom Penh, Coastal and Plateau) of Cambodia. The protein content of polished grains increased when rice was planted at a location with higher average temperature, but their lipid content decreased. The amylose content and degree of branching were not greatly affected by the minor temperature differences among the growing locations. Starch fine structures characterized by the chain-length distribution were significantly different among the cultivars, but not significantly among different locations. The results suggested that protein and lipid biosyntheses were more sensitive to the environmental temperature than that of starch in rice grains.     

移动通信基站在森林防火工作中的应用

移动通信基站基于卫星系统和通信系统的相关技术已相对成熟,在森林防火工作中已逐渐推广应用。本文根据工程实例,简要阐述了移动通信基站在森林防火工程项目中的应用。     

Demographic trends in Claremont California’s street tree population

The aim of this study was to quantify street tree population dynamics in the city of Claremont, CA. A repeated measures survey (2000 and 2014) based on a stratified random sampling approach across size classes and for the most abundant 21 species was analyzed to calculate removal, growth, and replacement planting rates. Demographic rates were estimated using a hierarchical Bayesian framework. The community-level (all species) median growth rate was 1.41% per year (95% CI: 1.21–1.65%) with Pinus brutia and Pistacia chinensis growing significantly faster than the community-level median. The community-level median removal rate was 1.03% per year (95% CI: 0.66–1.68%), with no significant differences between species and the community-level medium. Once removed, only 7.2% (95% CI: 4.4–12.9%) were replaced annually. Presence of overhead utility lines influenced tree removal rates while age, diameter-at-breast-height, and prior tree condition influenced tree growth. Overall live aboveground biomass in sampled sites was 713.29 Mg in 2000 and increased to 877.36 Mg by 2014. Biomass gain from growth outweighed loss from removals nearly three-fold; replacement contributed 0.5% of the total biomass gain. We conclude that to increase the resilience of the street tree population will require 1) an increase in percent of full stocking or biomass stock and 2) a shift in the species palette to favor species less vulnerable to pests and expected disturbance from climate change and 3) ongoing monitoring to detect departures from baseline demographic rates.     

基于SWOT分析的三明市全域森林康养产业发展对策

利用SWOT分析方法,对三明市发展全域森林康养产业进行优势、劣势、机遇和威胁分析,并针对存在的劣势和威胁提出了初步的对策与建议,以期为推进三明全域森林康养产业发展提供参考。     

落叶松油松人工混交林经营技术探讨

通过研究落叶松、油松混交林整个发育过程中不同阶段相应的经营管理措施，总结提出了一套切实可行的落叶松、油松混交林经营管理技术。其技术能有效提高林木生长速率，调整林分结构，优化树种组成，提高木材质量，为落叶松、油松混交林的经营管理提供技术支持。     

板栗低产林嫁接换冠成效的初步研究

对嫁接换冠技术在寿宁县清源乡龟洋茶场板栗果园上的应用效果进行了调查，结果表明：对投产的低产劣种板栗进行嫁接换冠，改劣换优，可保持板栗品种的优良特性，使低产劣种板栗树嫁接换冠后的第3年，95％的板栗均可挂果投产，总产量增长幅度达8．265倍；挂果株数提高了3．8倍，良种挂果株数提高了4．75倍，平均单价提高了3．7元/kg ，总产值提高了13．83倍，经济效益十分显著。     

滇西北退耕还林后续政策分析及发展对策

滇西北是云南省最为贫困的少数民族聚集地区之一,实行退耕还林政策10多年来取得了巨大的成效,随着退耕还林政策补助陆续到期,部分退耕农户生计将出现困难。对退耕还林后续政策进行分析,认为退耕还林补偿标准与现有物价水平不符,套种的规定过于保守,针对政策上的不足与实施过程中存在的作业设计不够规范、监管不力、档案管理不够规范等问题提出相关对策和建议。