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861.
应用大量的调查和试验数据,论述了红壤区耕地有机物质资源的种类、数量及分布状况;分析了目前有机物质利用的现状及存在问题;探讨了开发有机肥料资源的对策。 相似文献
862.
对广东省平远县稀土矿开采对土地资源的影响进行了初步的调查和分析。同时在已进行的植被恢复措施的基础上,对其效应作了初步的分析,评价了恢复措施对水土流失和土壤理化性质的影响,并据此提出了比较适合的植被恢复措施。 相似文献
863.
864.
云南省土著民族在长期生产实践中积累了丰富的知识,形成了特有的习俗。这些知识和习俗对保护当地生态环境和资源发挥了重大作用。本文从宗教信仰、民俗、耕作制度、栽培、选种等方面进行归纳,以期从中汲取有益于农业持续发展的精华。 相似文献
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866.
Lucas Ferrante Augusto Getirana Fabricio Beggiato Baccaro Jochen Schöngart Ana Cristina Monteiro Leonel Renato Gaiga Michel Varajão Garey Philip Martin Fearnside 《Conservation biology》2023,37(3):e14033
Given the speed at which humans are changing the climate, species with high degrees of endemism may not have time to avoid extinction through adaptation. We investigated through teleconnection analysis the origin of rainfall that determines the phylogenetic diversity of rainforest frogs and the effects of microclimate differences in shaping the morphological traits of isolated populations (which contribute to greater phylogenetic diversity and speciation). We also investigated through teleconnection analysis how deforestation in Amazonia can affect ecosystem services that are fundamental to maintaining the climate of the Atlantic rainforest biodiversity hotspot. Seasonal winds known as flying rivers carry water vapor from Amazonia to the Atlantic Forest, and the breaking of this ecosystem service could lead Atlantic Forest species to population decline and extinction in the short term. Our results suggest that the selection of morphological traits that shape Atlantic Forest frog diversity and their population dynamics are influenced by the Amazonian flying rivers. Our results also suggest that the increases of temperature anomalies in the Atlantic Ocean due to global warming and in the Amazon forest due to deforestation are already breaking this cycle and threaten the biodiversity of the Atlantic Forest hotspot. 相似文献
867.
K. A. Rosentrater T. L. Richard C. J. Bern R. A. Flores 《Resources, Conservation and Recycling》2003,39(4):341-367
Increasing production of corn masa for tortillas, chips, and related snack foods is resulting in large quantities of organic residuals requiring environmentally sound management. These byproduct streams appear suitable for use as livestock feed material, thus eliminating landfilling costs. Possibilities for developing livestock feed include direct shipping to livestock feeding facilities, blending prior to shipping, extrusion processing, pellet mill processing, and dehydration. To assess the viability of these options for reprocessing masa byproducts as livestock feed materials, an economic model was developed and applied to each of these alternatives. Through a series of simulation runs with this model, it was determined that direct shipping was by far the most inexpensive means of recycling masa processing residuals (10–57 $/Mg). Other alternatives examined in increasing order of costs included blending prior to shipping, extrusion, pellet mill processing (3–15, 5–18, and 4–18 times greater than direct shipping, respectively), while dehydration was clearly cost-prohibitive (33–81 times greater). Bagged feed was slightly more expensive to produce than bulk feed (1.1 times greater), and reprocessing costs increased as delivery distance increased, due to increased labor, equipment, and fuel costs, but decreased as byproduct generation rate increased, due to the development of the economies of scale. Alternately, based on a tipping fee of 50 $/Mg, the total estimated cost to landfill ranged from 65 to 112 $/Mg. Based on this cost analysis, direct shipping and feeding to livestock is the recycling option of choice for masa processing byproducts. Although specific details of process configurations and associated costs will vary, similar results are likely for other high moisture food processing residuals destined for utilization as livestock feed or components thereof. 相似文献
868.
869.
山西根瘤菌资源多样性与特异性研究 总被引:10,自引:0,他引:10
从山西不同生态条件下,采集豆科植物根瘤,经分离、纯化、回接原寄主,获得来自31属71种豆科植物寄主的纯根瘤菌株212株.对154株进行了BTB反应和生长速度测定,在YMA培养基上产酸快生型占97.4%.选用了其中50株,以快生型苜蓿根瘤菌(R.meliloti)和豌豆根瘤菌(R.leguminosarum)各3株为CK,进行了其它生理生化鉴定.结果表明,56株参试菌株均不产生3-酮基乳糖.山西分离的菌株能在蛋白胨肉汤上生长的13株;能利用柠檬酸盐的7株;石蕊牛奶反应,产酸的12株,其中酸凝的8株,产碱的30株,其中胨化的11株,石蕊还原的7株.唯一碳源和氮源利用比CK更广泛.对温度的适应范围宽.比CK有更强的耐盐、耐碱和对抗菌素的耐受能力 相似文献
870.
IntroductionWatershortageproblemisquiteseriousinmanycitiesofChina .Thereuseofmunicipalwastewaterisoneofthekeymethodstoreleasethisproblem .Makeupwaterforrecirculatingcoolingsystemisthelargestwaterusageinmanyfactories .Thewaterqualitystandardsforreclaimedwa… 相似文献