Results 21 to 30 of about 25,197 (189)
Shuitu Baochi Xuebao, 2007 条桑在河北省东部平原沙地和丘陵梯田广泛种植,与农作物间作是其主要栽培模式。2006年在河北省迁安市进行了桑粮间作田条桑根系断面积、根量、根系直径分布特征及其对土壤水分、养分影响的研究。结果表明：根系分布主要集中在20～40 cm土层内,此范围内的根系重量占总根量的60%～80%。根系以直径小于3 mm的细根居多,占总根量的30%～40%,大于7 mm的粗根数量很少,占总根数的5%～15%。平原沙地条桑根系主要分布在距桑丛中心100 cm范围内,桑丛外缘100 cm处的根量仅为总根量的6.52 ...
张俊娥 +5 more
doaj
Conservation Biology, EarlyView.Abstract Human development is a driver of global change and a major threat to biodiversity. Protected areas maintain and support biodiversity, but outside stressors, such as climate change and land use change, can negatively influence natural resources within protected areas.
Leah J. Rudge +2 more
wiley +1 more source
Shuitu Baochi Xuebao, 1994 该文通过对海堤林带树木根系及土壤抗冲，抗蚀和渗透性的测定分析，发现同一地段土壤的抗冲，抗蚀指数表土层大于底土层。树木根系，尤其是根径≤２ｍｍ的细根有较强的固特土壤功能，抗冲指数与根长，根量间有明显的相关性，单相关系数分别为０．９３２６和０．８２５６。吸机质含量高的土壤抗蚀性强，抗蚀指数大，与有机含量间的相关系为０．８９３１，与细根的根长和根量的相关性相对较低，单相关系数分别为０．８２１６和０ ...
张金池 康立新
doaj +2 more sources
Influence of Root Secretion Flavonoids on the Biogeochemistry Behavior of Cadmium in Avicennia marina (Forsk.) Vierh Rhizosphere [PDF]
, 2015 红树林生态系统主要分布于热带和亚热带的海岸潮间带，其具有独特的生态学和生物学特性，为污染物的吸附治理提供了最佳场所。然而，近年来，随着工业化、城市化和地区经济的快速发展，导致大量生活污水和工业废水流向红树林湿地，使得红树林生态系统面临越来越严重的重金属污染，从而使得滨海湿地面临着日益严峻的重金属污染。进入红树林湿地的污染物最先在红树植物根际区进行一系列形态转化等过程，而后被植物吸收累积。因此，红树林根际区重金属化学行为已经成为近年来污染生态学的研究热点。 类黄酮是植物体内广泛存在的一类重要次生代谢产物 ...
李健
core
A more‐than‐human political ecology of Indonesian songbird trade
Conservation Biology, EarlyView.Abstract Since its inception, conservation science has considered wildlife trade a problem. In focusing on conservation outcomes, conservationists almost completely ignore the welfare of traded animals and plants and the harms they endure. We developed a political ecology approach that incorporates the interconnectedness of people with animals and ...
Sicily Fiennes +9 more
wiley +1 more source
International Journal of Applied Linguistics, EarlyView.ABSTRACT Research on English‐Medium‐Instruction (EMI) highlights inadequate support for students transitioning from L1‐medium‐instruction to EMI. To date, little research has focused on how L2 students’ adaptation to an EMI environment influences their L2 learning motivation (LLM).
Kevin W. H. Tai
wiley +1 more source
International Journal of Applied Linguistics, EarlyView.ABSTRACT This computational linguistic study analyzes 8743 Rednote posts to examine how sentiment, emotion, and content domain collectively shape social comparison dynamics on social media. We identify four key findings: (1) an emotional gradient, where upward comparison content exhibits the highest sentiment scores and downward comparison the lowest; (
Michelle Mingyue Gu +7 more
wiley +1 more source
Study on the nitrogen removal process and influencing factors in the rhizosphere of Sesuvium portulacastrum floating bed [PDF]
, 2016 大气是地球氮元素储量最大的氮库，由于氮气的三键结构十分稳定，打开它所需的能量较高，因此在工业革命以前，主要靠闪电固氮和生物固氮将其转化为人和生物可以利用的含氮化合物。然而随着人类社会的不断发展，为了满足人们生产生活的需要，大量氮元素被通过工业的方式固定下来，并随着化肥的滥用积累在环境中，造成氮循环的破坏，并产生水体富营养化现象。富营养化带来的恶果就是水体藻类大量繁殖，溶解氧急剧降低，造成鱼虾等水生生物的死亡等。因此，想要根除富营养化现象就必须将水体过量的氮、磷营养盐从水体脱除 ...
仇元
core
International Journal of Applied Linguistics, EarlyView.ABSTRACT This study examines how foreign language teachers’ beliefs about the medium of instruction and translanguaging evolve over time by revisiting three in‐service teachers twelve years after their initial interviews. Using a qualitative longitudinal design, the study traces how translanguaging was initially framed as pedagogically deficient but ...
Danping Wang
wiley +1 more source