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1.
建立大青山国家级自然保护区，是自治区党委、政府统揽全局、着眼长远、与时俱进做出的战略决策，是应对全球气候变暖、生物多样性锐减和建设现代林业的科学把握，是实现建设祖国北方重要生态屏障战略目标的具体实践，深刻反映了落实科学发展观与构建和谐社会的时代要求，集中地体现了“生态优先”、“生态建设是内蒙古最大的基础建设”的指导思想，是建设和谐内蒙古的重要内容。 相似文献
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在老地方—村东大榆树下,翠枝早就来了。她左顾右盼还不见大柱子来。每天歇晌,他俩总是脚前脚后到,今天怎么了?翠枝踮起脚尖,手打眼罩,村里、田野、四下瞭望,都不见大柱子的身影。盛夏的中午,太阳烤得大地发烫,口干舌燥,要不是在大树荫下,简直能把人晒死。“该死的大柱子!”翠枝心里骂道。“等来了,非狠狠地擂他几拳头不可!都到什么时候了,还没个正形…。”她想着、怨着、气得把 相似文献
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推荐理由：
本文提出了人与森林资源和谐共处的重要性、必然性以及保护森林资源、科学发展林业产业的紧迫性。全文特色亮点在于以史为鉴．符合本刊100期里程碑式的史鉴价值诉求。 相似文献
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大兴安岭东部林区分布着大面积、多类型的湿地资源，这些湿地资源在大兴安岭地区的生态环境建设中发挥着重要作用。近年来，由于认识上的不足，在地方经济发展建设的过程中，存在着不同程度的破坏湿地生态环境现象。文章从几个方面加以论述，并就湿地资源的保护问题提出一些观点和看法。 相似文献
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2013年，地板和木门行业虽然没有发生翻天覆地之变化，但同样是一个不缺少精彩的江湖，有实力的老牌企业与异军突起的新锐、国产与进口、线上与线下，总有那么一些事件推动整个林业产业的进步，也正是这些创新和改变，不断影响着国人的日常生活。 相似文献
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一是要尽快完善保护区组织机构和管理机制建设。要尽快建立健全大青山自然．保护区管理局——管理分局——保护管理站三级机构管理体系。要进一步加快《内蒙古大青山自然保护区管理办法》的制订和修改工作，力争早日出台，使保护区尽快走上依法治理轨道。同时，保护区管理局要不断强化自身建设，实行规范化管理。 相似文献
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安雅 《绿色中国(A版)》2008,(8)
他们刚走出校门,步入工作岗位,既不用照顾父母,也没有妻儿牵挂;他们挣得不少,但花得更多,超前消费是他们现行的生活理念,所以他们的钱包里至少都有两张以上的信用卡;一边大肆享受生活,一边却喊着贫穷的口号,这就是80后职场新人的生活方式。但走过潇洒的单身期后,身无分文的新新人类们该如何建立家庭经济基础呢?今天我们就针对不同类型的新新人类的不同理财误区进行分析。 相似文献
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定植两年的幼树稳定成活后,在第3年跟踪29块10M×10M样地幼树各器官的生长情况,发现不同植株在不同月份的生长具有极显著的差异,各器官生长具有不同的相关性。树高生长与地径、总叶量、平均叶量、平均枝条大小、平均枝长等极显著相关,与分枝数负显著相关。不同植株的不同器官对树高的回归特征不同,种群中地径、总叶量对树高的回归系数较大,而分枝数对树高的回归系数最小,为-0.029。 相似文献
11.
不同林型土壤水、气、热及养分状况的观测分析 总被引：1，自引：0，他引：1
通过对20年生的人工阔叶油松混交林和油松纯林的土壤理化性质，水热状况的观测分析，试图了解不同林型对土壤条件的影响，为今后选择最佳的混交类型，保持良好的土壤生态环境，提供有益的数据。 相似文献
12.
Soil CO2 levels reflect CO2 production and transport in soil and provide valuable information about soil CO2 dynamics. However, extracting information from soil CO2 profiles is often difficult because of the complexity of these profiles. In this study, we constructed a simple numerical
model that simulated soil CO2 dynamics and performed sensitivity analyses for CO2 production rates, soil water content and temperature, and gas diffusivity at the soil surface to clarify the relationships
among these parameters. Increased soil surface CO2 flux did not always coincide with higher soil CO2 concentrations; increased CO2 production at shallow depths had little effect on soil CO2 concentrations, while the opposite may be true for high levels of soil water content. Higher soil CO2 concentration did not always coincide with greater soil surface CO2 flux; under high soil water conditions, soil surface CO2 flux sometimes decreased despite increased soil CO2 concentration. Increases in soil water content did not always enhance both soil surface CO2 flux and soil CO2 concentration. Under high soil water conditions, increases in soil water content could lower soil surface CO2 flux and increase soil CO2 concentration. Increases in soil temperature resulted in greater soil surface CO2 flux and higher soil CO2 concentration in our simulation (extremely high temperatures were not assumed in this study). Gas diffusivity in very shallow
layers did affect, albeit weakly, soil CO2 concentration. The findings of this study may help direct future observations and aid in the interpretation of their results. 相似文献
13.
Jiayao Zhuang Jinchi Zhang Bo Zhang Hongyan Luo Xiaying Huang Jun Fu 《Frontiers of Forestry in China》2009,4(3):323-329
The distribution of root biomass was studied in different soil layers (0–10, 10–20, 20–30, 30–40 cm) by means of a “study
plot” method for various plant species in the Shangshe Catchment area in the Dabie Mountains, Anhui Province. The number and
lengths of root samples were recorded. In each study plot, anti-scourability of soils in corresponding soil layers was measured
with a C.C. Suoboliefu anti-scourability instrument. The results showed the following: 1) The root system was largely distributed
in the 0–40 cm soil layer and the number of roots was the largest in the surface soil layer. Fine roots<1 mm in diameter predominated
in root length. 2) In the same section, the anti-scourability indices of the surface soil layer were larger than those of
other soil layers in the various plant species. The tree root system, especially the fine roots<1 mm in diameter, are highly
instrumental in controlling soil losses. Correlation coefficients of length, number and density of fine roots and the anti-scourability
index were 0.8173, 0.7159 and 0.6434, respectively. The length of fine root is a key factor in the anti-scourability soil
index. This index is closely correlated with the non-capillarity of each soil type, indicating that forests have a strong
soil stabilizing function, because their root systems improve physical soil properties and ultimately are responsible for
the establishment of a biosoil system with an anti-scourability index.
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Translated from Science of Water and Soil Conservation, 2007, 5(6): 15–20 [译自: 中国水土保持科学] 相似文献
14.
Glomalin-related soil protein(GRSP)sequesters large amounts of carbon and plays important roles in maintaining terrestrial soil ecosystem functions and ecological restoration;however,little is known about GRSP variation in 1-m soil profiles and its association with stand characteristics,soil properties,and climatic conditions,hindering GRSP-related degraded soil improvement and GRSP evaluation.In this study,we sampled soils from 1-m profiles from poplar(Populus spp.)shelterbelts in Northeast China.GRSP contents were 1.8–2.0 times higher in the upper 40 cm soil layers than at 40–100 cm.GRSP-related soil organic carbon(SOC)sequestration in deeper soil layers was*1.2 times higher than in surface layers.The amounts of GRSP-related nutrients were similar throughout the soil profile.A redundancy analysis showed that in both surface and deeper layers,soil properties(pH,electrical conductivity,water,SOC,and soil nutrients)explained the majority of the GRSP variation(59.5–84.2%);the second-most-important factor in GRSP regulation was climatic conditions(temperature,precipitation,and altitude),while specific shelterbelt characteristics had negligible effects(<5%).Soil depth and climate indirectly affected GRSP features via soil properties,as manifested by structural equation model analysis.Our findings demonstrate that GRSP is important for carbon storage in deep soils,regardless of shelterbelt characteristics.Future glomalin assessments should consider these vertical patterns and possible regulating mechanisms that are related to soil properties and climatic changes. 相似文献
15.
Oliveira Fernanda C. C. Ferreira Gabriel W. D. Santos Rafael S. Aubrey Doug P. Araújo Elias F. Silva Ivo R. 《New Forests》2021,52(5):737-757
Relatively few studies have documented the impacts of afforestation, particularly production forestry, on belowground carbon dioxide (CO2) effluxes to the atmosphere. We evaluated the changes in the soil CO2 efflux—a proxy for soil respiration (Rs)—for three years following a native grassland conversion to eucalypt plantations in southern Brazil where minimum tillage during site preparation created two distinct soil zones, within planting row (W) and between-row (B). We used root-exclusion and carbon (C)- isotopic approaches to distinguish Rs components (heterotrophic-Rh and autotrophic-Ra respirations), and a CO2 profile tube (1-m deep) to determine the concentration ([CO2]) and isotopic C signature of soil CO2 (δ13[CO2]). The soil CO2 efflux in the afforested site averaged 0.37 g CO2 m?2 h?1, which was 56% lower than the soil CO2 efflux in the grassland. The δ13CO2 in the afforested site ranged from ? 14.1‰ to ? 29.4‰, indicating a greater contribution of eucalypt-derived respiration (both Rh and Ra) over time. Higher soil CO2 efflux and lower [CO2] were observed in W than B, indicating that soil preparation creates two distinct soil functional zones with respect to C cycling. The [CO2] and δ13[CO2] decreased in both zonal positions with eucalypt stand development. Although the equilibrium in C fluxes and pools across multiple rotations is needed to fully account for the feedback of eucalypt planted forests to climate change, we provide quantitative information on soil CO2 dynamics after afforestation and show how soil preparation can leverage the feedback of planted forests to climate change.
相似文献16.
17.
The effect of thinning on microbial biomass C, N and basal respiration in black pine forest soils in Mudurnu, Turkey 总被引：1，自引：0，他引：1
İlyas Bolat 《European Journal of Forest Research》2014,133(1):131-139
Reducing the canopy cover (e.g., forest thinning) is one of the most commonly employed forest silvicultural treatments. Trees are partially removed from a forest in order to manage tree competition, thus favoring the remaining and often the most valuable trees. The properties of the soil are affected by forest thinning as a result of changes in key microclimatic conditions, microbial communities and biomass, root density, nutrient budgets and organic matter turnover. The aim of this study was to determine the soil microbial biomass C, N and respiration (basal respiration) in a black pine (Pinus nigra Arn. subsp. pallasiana) forest in the Mudurnu district of Bolu Province (Western Black Sea Region, Turkey). Whereas forest thinning was found to cause increases in the soil temperature, microbial biomass C and N and organic C, it was found to decrease the soil moisture, basal respiration and metabolic quotient (qCO2). As expected, soil organic C exhibited a strong impact on soil microbial biomass C, N and basal respiration. It was concluded that the influence of forest thinning on the microbial biomass and soil respiration was the combined result of changing microclimatic conditions and soil properties, such as forest litter, soil temperature, soil moisture, soil pH and soil organic matter. 相似文献
18.
Growth and yield of 12-year-old loblolly pine (Pinus taeda L.) plantations were compared among five subsoil textures, seven site preparation methods, with and without phosphorus fertilizer. Phosphorus broadcast before planting increased the mean size of the loblolly pine trees. However, soil differences significantly influenced stand survival, and the method of site preparation significantly affected total stand yield. Therefore, the influence of phosphorus on total stand yield depended on soil type and site preparation method. The site preparation-fertilizer combinations yielding the most volume per soil type were: on the Lucy, Ruston, and Wagram soils, shear-windrow site preparation with phosphorus; on the Kirvin and Shubuta soils, chop-burn-harrow site preparation without phosphorus; on the Calloway and Henry soils, double chopping without phosphorus; on the Sawyer soil, chopburn-harrow site preparation with phosphorus; and on the Boswell, Cadeville, Gore, and Susquehanna soils, shear-windrow-harrow site preparation without phosphorus. Soil differences and phosphorus fertilization influenced the incidence of fusiform rust in 12-year-old stands of loblolly pine. 相似文献
19.
The effects of soil organic matter, soil moisture, shading and ash on white pine (Pinus strobus L.) emergence were investigated using soil monoliths in greenhouse experiments. White pine seedling emergence increased with soil organic matter removal, and levelled with the elimination of the litter and fermentation layers, where seedling emergence did not significantly increase further. Increased shade and soil moisture levels also improved seedling emergence whereas ash had no or little impact on white pine seedling emergence. The silvicultural implications of these findings are discussed with regard to white pine management. 相似文献
20.
Shoji Noguchi Abdul Rahim Nik Zulkifli Yusop Makoto Tani Toshiaki Sammori 《Journal of Forest Research》1997,2(3):125-132
Field observations were conducted at Bukit Tarek Experimental Watershed in Peninsular Malaysia to investigate the relationship
between rainfall-runoff responses and variation in soil moisture in a tropical rain forest. Stormflow depended strongly on
the antecedent wetness as represented by the initial runoff rate. Though heavy rains fell in almost every month, the soil
moisture decreased when fair weather was sustained. The soil moisture depleted and became dry at 160 cm depth during occasional
dry spells. During dry conditions, streamflow responded quickly to rain events but declined rapidly after the rain stopped,
and the soil moisture of surface soil (≤20 cm) increased but remained dry at lower depths (≽80 cm). This suggests that the
rain water was mostly retained in the soil and only small proportions appeared as stormflow. As soil moisture conditions became
wetter, the recession limb of the storm hydrograph was more gradual. Stormflow volume increased with increasing soil moisture.
During wet conditions, the soil profile was moist at all parts of the slope. The hydraulic gradient was around 1.0 and there
was downward soil water flux, which followed the pressure gradient. This suggests that subsurface flow from the upper part
of the slope might also be important for stream-flow production. Positive pressures were observed at 10 cm and 160 cm depths
during large storms. The behavior of the subsurface flow might be an important determinant of stormflow. 相似文献