人与自然和谐相处的水土保持理念探讨

人与自然不和谐相处就会加剧环境恶化、危及国家生态安全、制约经济社会可持续发展 ,因此要转变观念 ,调整思路 ,突出水土资源的高效利用、有效保护和优化配置 ,分类指导、整体推进 ,高度重视生态自我修复 ,应用社会化机制 ,加快新技术的研究和推广 ,促进人与自然和谐相处。     

构建优质水土生态环境 促进人与自然和谐发展——福建省三明市水土保持工作简况

三明市水土保持委员会及其办公室成立于1981年，市、县(市、区)两级设立13个水土保持委员会及其办公室，13个水土保持监督站，2个水土保持试验站，2个水土保持监测站，现有水土保持工作人员62人。     

以人与自然和谐相处的理念为指导 正确把握人工治理与生态自我修复的关系

生态自我修复同人工治理一样 ,都是促进人与自然和谐相处的重要手段 ,无论从社会角度还是从技术上来看 ,都存在着优势和劣势 ,只有把二者有机结合起来 ,才能更好地防治水土流失。生态修复作为一项新的工作 ,需要我们统一认识、制定规划、加强协调、增加投入、搞好示范、配套法规、开展监测等积极探索 ,大力推进     

牢固树立和认真落实科学发展观 努力促进长江上中游人与自然和谐发展

"长治"工程自1989年实施以来,初步摆脱了长江上游严重的水土流失困境,显著改善了治理区群众生产生活条件,加快了广大治理区群众脱贫致富的步伐,人为水土流失得到有效遏制,共治理水土流失面积8万多km2。工程建设的宝贵经验是:强化行政推动,加强统筹协调;强化科学防治,拓宽工作思路;强化项目管理,不断创新机制;强化预防保护,坚持依法行政。新时期和新形势下,要充分认识长江上中游水土保持重点防治工作的艰巨性、重要性和紧迫性,以科学发展观为指导,提高认识,明确目标,创新思路,加快发展。提出了当前应抓好的四项工作。     

建立"人与自然和谐度指标评价体系"的构想

人与自然和谐共处是可持续发展最核心的问题,是科学发展观在工作中的具体体现,对我国人际关系、人与自然关系的思想意识领域有着影响的深远。因此,建立人与自然和谐度指标评价体系是很有必要的。     

Heavy metal accumulations in forest soils along an urban- rural gradient in Southeastern New York,USA

Water, Air, & Soil Pollution - Heavy metal contents and concentrations of forest floor and mineral soil were determined in nine oak stands situated along an urban-rural gradient. Twelve...     

美国俄勒冈州有机与传统农业生态系统间土壤生物区的比较

Soil samples at 0--10 cm in depth were collected periodically at paired fields in Corvallis, Oregon, USA to compare differences in soil microbial and faunal populations between organic and conventional agroecosystems Results showed that the organic soil ecosystem had a significantly higher (P < 0.05) average number or biomass of soil bacteria; densities of flagellates, amoebae of protozoa; some nematodes, such as microbivorous and predaceous nematodes and plant-parasitic nematodes; as well as Collembola. Greater numbers of Rhabditida (such as Rhabditis spp.), were present in the organic soil ecosystem while Panagrolaimus spp. Were predominant in the conventional soil ecosystem. The omnivores and predators of Acarina in the Mesostigmata (such as Digamasellidae and Laelapid), and Prostigmata (such as Alicorhaiidae and Rhagidiidae), were also more abundant in the organic soil ecosystem. However, fungivorous Prostigmata (such as Terpnacaridae and Nanorchestidae) and Astigmata (such as Acarida) were significantly higher (P < 0.05) in the conventional soil ecosystem, which supported the finding that total fungal biomass was greater in the conventional soil ecosystem. Seansonal variations of the population depended mostly on soil moisture condition and food web relationship. The population declined from May to October for both agroecosystems. However, higher diversities and densities of soil biota survived occurred in the organic soil ecosystem in the dry season.     

Cumulative estimates of sea turtle bycatch and mortality in USA fisheries between 1990 and 2007

Sea turtles interact with a variety of fishing gears across their broad geographic distributions and ontogenetic habitat shifts. Cumulative assessments of multi-gear bycatch impacts on sea turtle populations are critical for coherent fisheries bycatch management, but such estimates are difficult to achieve, due to low fisheries observer effort, and a single-species, single-fishery management focus. We compiled the first cumulative estimates of sea turtle bycatch across fisheries of the United States between 1990 and 2007, before and after implementation of fisheries-specific bycatch mitigation measures. An annual mean of 346,500 turtle interactions was estimated to result in 71,000 annual deaths prior to establishment of bycatch mitigation measures in US fisheries. Current bycatch estimates (since implementation of mitigation measures) are ∼60% lower (137,800 interactions) and mortality estimates are ∼94% lower (4600 deaths) than pre-regulation estimates. The Southeast/Gulf of Mexico Shrimp Trawl fishery accounts for the overwhelming majority of sea turtle bycatch (up to 98%) in US fisheries, but estimates of bycatch in this fishery are fraught with high uncertainty due to lack of observer coverage. Our estimates represent minimum annual interactions and mortality because our methods were conservative and we could not analyze unobserved fisheries potentially interacting with sea turtles. Although considerable progress has been made in reducing sea turtle bycatch in US fisheries, management still needs improvement. We suggest that sea turtle bycatch limits be set across US fisheries, using an approach similar to the Potential Biological Removal algorithm mandated by the Marine Mammal Protection Act.     

Correlation between Microcrustaceans and Environmental Variables along an Acidification Gradient in Sudbury, Canada

Multivariate methods were used to relate microcrustacean (pelagic and littoral) richness and composition (presence/absence) to water quality and other environmental variables. All acidification variables (pH, aluminium, ANC) showed significant correlation with both species richness and composition. The variation in microcrustacean richness was best explained by the combination of dissolved organic carbon (DOC), fish species richness and lake area. Of 16 variables tested, pH showed strongest correlation with the main gradient in the crustacean composition explaining between 13 and 16% of the variance in the species data (CCA). pH, elevation, lake area, average depth, DOC, conductivity and fish species richness explained 30–54% of the total variance. Stronger correlation was obtained between species composition and environmental data in analyses which included the between-year differences than analyses based on the cumulative species records. Analyses based on the pelagic species exclusively gave similarly stronger correlation than analyses based on all crustacean species. Small changes in the species composition during the three years of study may be an indication of recovery of microcrustaceans in Killarney lakes.     

Sedimentary profiles of pollution marker chemicals along a large tributary of Chesapeake Bay (mid-Atlantic USA)

Journal of Soils and Sediments - Molecular markers in environmental geochemistry include natural product or pollutant chemicals in sediments that are indicative of discharge sources or emission...     

土壤微量元素与人类活动强度的对应关系

本文以天津地区为例 ,在分析影响土壤中微量元素含量各种人为因素的基础上 ,利用天津地区人类活动强度对土壤微量元素含量变化的联系、不同土地利用方式土壤微量元素含量的变化规律 ,探讨土壤微量元素含量变化与人类活动强度之间的联系。研究发现 ,Hg、Cd、Se元素是最敏感的地球化学因子 ,能够反映天津地区土壤环境受人类活动的影响程度 ,利用土壤环境中Hg、Cd、Se的变化特征 ,可以确定本地区土壤环境受人类影响程度的大小