四川省植被覆盖时空演变及未来变化趋势分析

四川省地处长江上游,是长江流域重要的生态屏障;解析该区域植被覆盖的时空演变特征,对长江上游的生态环境修护与治理具有重要意义。基于长时间序列的MODIS NDVI数据,解析2000~2016年间四川省植被的空间分布格局与时间变化特征;采用趋势分析法和Hurst指数,预测未来植被的变化趋势及持续性。结果表明:(1)四川省NDVI多年平均值为0.50,植被覆盖整体上呈现川东高于川西的空间分布特征;(2)2000~2016年间,四川省的NDVI值在0.48至0.53之间波动,整体呈上升趋势,增长率为0.002 5/a;(3)植被覆盖度在未来变化将呈现改善大于退化的趋势;植被持续性改善的面积大于持续性退化的面积。     

Transfer learning between crop types for semantic segmentation of crops versus weeds in precision agriculture

Agricultural robots rely on semantic segmentation for distinguishing between crops and weeds to perform selective treatments and increase yield and crop health while reducing the amount of chemicals used. Deep‐learning approaches have recently achieved both excellent classification performance and real‐time execution. However, these techniques also rely on a large amount of training data, requiring a substantial labeling effort, both of which are scarce in precision agriculture. Additional design efforts are required to achieve commercially viable performance levels under varying environmental conditions and crop growth stages. In this paper, we explore the role of knowledge transfer between deep‐learning‐based classifiers for different crop types, with the goal of reducing the retraining time and labeling efforts required for a new crop. We examine the classification performance on three datasets with different crop types and containing a variety of weeds and compare the performance and retraining efforts required when using data labeled at pixel level with partially labeled data obtained through a less time‐consuming procedure of annotating the segmentation output. We show that transfer learning between different crop types is possible and reduces training times for up to 80%. Furthermore, we show that even when the data used for retraining are imperfectly annotated, the classification performance is within 2% of that of networks trained with laboriously annotated pixel‐precision data.     

相邻雷达回波强度差异分析

文章选用2017-12-13的青浦站和南通站体扫数据和单站格点CAPPI数据,利用时空一致性匹配法和单站格点数据等距离线法对两站雷达回波强度差异情况进行了研究,并分析了两种算法可能存在的误差,结果表明:单站格点数据等距离线法要优于时空一致性匹配法,更适用于单部雷达体扫数据的相邻雷达回波差异对比;在雷达基数据正确的情况下,时空一致性匹配法误差主要来源于做不到真正的时空匹配一致,格点数据等距离线法误差主要来源于生成格点数据时插值算法不完善。     

淹水区边坡的生态型护坡技法及其耐久性研究

通过植生袋状垫（一种新型生态植生材料）、生态混凝土（多孔、透水性混凝土）、卵石（自然石）等近自然界材料的不同组合，创作出的最新生态型护坡技法来对淹水区坡面进行设计、护坡，不仅可以充分保证护坡工程安全性、经济性，而且能起到对生态环境维持和改善的功能。针对国家863“十五”重大科技专项“镇江城市水环境质量改善与生态修复技术研究与示范”总课题第三分项中的生态堤淹水区坡面．采用三种不同的生态护坡技法进行了现场实施，同时对生态护坡技法中的生态混凝土的耐久性等进行了调查、研究和评价。结果表明：所提出的生态护坡技法能够谋求和保证与生态系统的调和或共生、创造舒适的环境，并且所用生态混凝土具有良好的耐久性。     

HYDRAULICS, WATER QUALITY AND VEGETATION CHARACTERISTICS OF GROUNDWATER-FED OPEN DITCHES

A novel peatland management strategy to utilise the high nutrient-retention potential of degenerated peatlands has been implemented in Northern Germany. The effect of raised water levels and extensive land-use management on hydraulic properties, water quality and vegetation characteristics of heavily vegetated and groundwater-fed open ditches, was investigated at the River Elder Valley - a nationally important wetland case study. A better understanding of the effect of vegetation on the temporal flow patterns and the hydraulic retention times is of high scientific interest, especially for improving nutrient standards in lowland rivers. Within-ditch vegetation and other hydraulic obstructions, including accumulated silt and organic debris, increase the hydraulic retention time and lead to an improvement of the water quality along the open ditch. Lower parts of the open ditches were flooded by the River Elder, due to the absence of a mowing scheme during late summer     

锚固土工网复合植被护坡技术及其工程应用

阐述了锚固土工网复合植被护坡技术的概念和原理,结合具体工程实例,通过稳定计算分析,从经济及安全等角度进行了综合研究,并提出了综合治理措施,收到了良好的效果。     

边坡绿化种植在香港的应用

概述了在边坡表面进行绿化种植的基本原理及其综合效应，详细介绍了香港地区的边坡绿化种植技术，包括设计思路、设计过程、施工技术和维护管理等几个方面，并为当前中国内地边坡绿化种植技术的推广和研究提出了建议。     

Olive mills wastewater treatment by combined membrane processes

The purpose of this work was to verify the combined application of membranes and adsorption processes to the treatment of vegetation waters coming from olive oil factories. The described pilot plant worked for about 6 months using polysulfone ultrafiltration membranes, absorbing polymers and polypiperazine amide reverse osmosis membranes. The process was optimized so that from wastewater entering with a COD content of about 90,000 ppm it was possible to obtain a COD reduction of about 99% with the recovery of polyphenols to use in alimentary industries and of a “concentrated paste” for oil extraction, phurphurale production or combustion. Also evaluated was the economical feasibility of industrial application calculating that the total cost of the treatment was close to 3 c per liter.     

植被增加边坡降雨入渗对边坡稳定性影响研究

植被根系提高土壤渗透性和抗侵蚀性,植被盖度越大径流起始时间越长,植被提高边坡的入渗率和减少土壤流失相互促进,共同作用的结果是保持水土,所以植被增加边坡降雨入渗的作用是十分显著的.大多数植物的根系分布在浅层,根际区土壤储水能力强,由于植被对根际区下层土壤的渗透性影响不大,而且认为植被对降雨入渗对根际区土壤水分的影响明显,而对边坡根际区下层土壤水分影响不明显,植被增加边坡降雨入渗不影响边坡深层稳定性.     

“食·疗·景”：岭南传统村落生活空间植被特征解析—以肇庆蕉园古村为例

传统村落人居环境生活空间植被与村民日常生活联系紧密。本文以广东肇庆地区蕉园古村为研究对象,采用现场调研及访谈法,分析其传统生活空间主要植被的"食·疗"功效及地域性景观价值。并就蕉园古村植被现状进行调查,结合岭南医学与中医养生理论,就其与村民日常"食·疗"生活的深层联系进行解析,包括"茶饮防病"、"食治调养"、"外治疗疾"3个层面。同时从物质性与精神性2个层面,就其生活空间植被所体现的地域性景观价值进行阐述,初步阐明了岭南传统村落生活空间植被之"食·疗·景"特征与应用机制,揭示了传统村落生活空间植被与村民日常养生保健的深层关系,为当代人居环境地域养生景观营造提供参照。