黑土区水土保持生态修复模式探讨

从黑龙江省水土流失现状出发,阐述了水土流失的原因,对目前已经应用的水土保持生态修复模式进行总结,并提出了今后黑土区水土保持生态修复的对策。     

黑龙江省黑土丘陵侵蚀区产业结构关系的研究

文章阐述了黑土丘陵区水土流失的状况,水土流失的面积占该地区总土地面积的44%,土壤侵蚀模数高达3 500 t.km-2.a-1,每年减少黑土层0.4～0.5 cm。总结了水土流失的原因,并根据该地区的自然、经济因素,制定了治理水土流失的原则和方法,为该地区的水土流失治理提供了科学依据。     

黑土区水土保持生态修复模式探讨

本文从黑龙江省水土流失现状出发,阐述了水土流失的原因,对目前已经应用的水土保持生态修复模式进行总结,并提出了今后黑土区水土保持生态修复的对策。     

论生态修复在黑龙江省水土流失治理工程中的优化作用

通过对生态修复的涵义、理论、实践及模式的论述，研究分析了生态修复对黑龙江省黑土区水土流失重点治理工程中的优化作用，指出了水土流失治理工程与生态修复相结合，既有利于对治理工程的保护，又有利于生态环境的改善，可以实现水土流失治理工程的可持续发展。     

沙棘在黑土区恢复生态、治理水土流失中的作用

黑土区种植沙棘，对水土流失治理、遏制土地沙漠化起到极大的作用。种植沙棘具有投资少、产量高、效益好、技术易掌握等优点，获得了很好的经济效益和社会效益。是农村调整产业结构，农民脱贫致富的好途径。     

东北黑土地水土流失问题分析及对策

由于人口的急剧增长和人类的过度开垦,东北黑土地的生态环境日益恶化,黑土资源流失严重.从东北黑土地的现状入手,分析了水土流失的原因:不合理开垦、耕作方式不科学、农业比较收入低致抛荒严重.提出了解决问题的对策:政府要加强领导、开展深入地宣传、建立管护责任、因地制宜采取治理措施等.     

黑龙江省西部农田林网区水土流失成因与防治对策

本文针对黑龙江省西部农田林网区水土流失日趋严重状况的调查 ,对水土流失现状进行了论述 ,并对水土流失的成因及危害进行了详细阐述 ,提出了防治水土流失的对策 ,为黑龙江省西部农田林网区水土流失治理工作提供理论参考     

浅议晋西地区水土保持与农业经济发展

1　晋西地区水土环境形势严峻晋西水土流失区地处黄土高原东部 ,黄河中游晋陕峡谷东岸 ,西以黄河为界 ,东至晋中盆地 ,南抵汾河入黄河之滨 ,北达山西边境 ,行政区包括 2 8县。目前这里水土资源紧缺 ,水土流失加剧 ,生态环境恶化。依据地貌特征 ,晋西水土流失区可分为晋西黄土高原沟壑区、晋西黄土丘陵沟壑区、晋西黄土缓坡丘陵区 3个类型区。晋西水土流失区土地总面积 4 .6万 km2 ,占全省总面积的 2 9.6 %。其中 ,耕地为 86 .5万 km2 ,人口36 2 .6万 ,区内广泛为黄土所覆盖 ,植被稀疏 ,水土流失面积达 3.3万 km2 ,占总面积的 71.7% ,土壤侵…     

防护林空间密度分布与水土流失强度关系分析

利用高分二号卫星影像并通过差值植被指数(DVI)提取防护林空间信息,通过网格分析法计算防护林的空间密度,基于Landsat 8 OLI数据,运用USLE水土流失方程测水土流失强度,分析德惠市防护林空间密度分布与水土流失强度的相关性,结果表明:德惠市防护林空间密度的最小值为0、最大值为0. 213、平均值为0. 007、标准差为0. 014;水土流失强度的最小值为0、最大值为17 278、平均值为1 045、标准差为836。有防护林分布的网格内水土流失强度比无防护林分布的网格低788,差异显著。水土流失强度随防护林空间密度呈先下降后上升的趋势,当防护林空间密度分布在0. 04～0. 06时,网格内水土流失强度达到最小值,占研究区0. 032%,无防护林分布的网格占研究区的68. 2%。     

扩大林草比重 防止水土流失

凉城县总土地面积3,455平方公里,其中山区占54.4％,丘陵区占20％。全县水土流失面积达2,434平方公里,占总土地面积的70％。每年平均流失表土3毫米,使黑土变成黄土,黄土变成沙土,沙土流成沟壑。水土流失严重的地方,种地没有土,发展牧业没有草场。全县土地多为疏松的沙质土,坡地多在25度     

用土壤养分系统研究法评价杨树人工林土壤养分状况

A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach(SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P,K, Zn), -N(P, K, Zn), -P(N, K, Zn), -K(N, P, Zn), Mg(N, P, K, Zn, Mg), -Zn (N,P,K), 2P(N, 2P, K, Zn), 2K(N, P, 2K, Zn), and 2N 2P 2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar.The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform perfectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation.     

土壤温度和水分对长白山3种温带森林土壤呼吸的影响

为了研究土壤温度和土壤含水量对阔叶红松林(山地暗棕壤)、云冷杉暗针叶林(山地棕针叶林土壤)和岳桦林(生草森林土)的土壤呼吸的影响,于2001年9月在长白山进行了土壤实验。利用增加土壤样柱的含水量,将土壤含水量分为9%,、21%、30%、37%和43%5个等级,土壤样品分别在0、5、15、25和35的温度下保持24小时。阔叶红松林土壤在0~35范围内,土壤呼吸速率与温度呈正相关。在一定的含水量范围内(21%~37%),土壤呼吸随含水量的增加而升高,当含水量超出该范围,土壤呼吸速率则随含水量的变化而降低。土壤温度和水分对土壤呼吸作用存在明显的交互作用。不同森林类型土壤呼吸作用强弱存在显著差异,大小顺序为阔叶红松林>岳桦林>云冷杉暗针叶林.红松阔叶林土壤呼吸作用的最佳条件是土壤温度35,含水量37%;云冷杉暗针叶林下的山地棕色针叶土壤呼吸作用的最佳条件是25,21%;岳桦林土壤呼吸作用的最佳条件是35,含水量37%。但是,由于长白山阔叶红松林,云冷杉林和岳桦林处在不同的海拔带上,同期不同森林类型土壤温度各不相同,相差4~5,所以野外所测的同期的山地棕色针叶林土呼吸速率应低于暗棕色森林土呼吸速率,山地生草森林土呼吸速率应高于山地棕色针叶林土的呼吸速率。图2表1参25。     

PAHs在樟树根际和非根际土壤中的分布特征

对樟树根际土与非根际土壤中PAHs分布特征进行了研究。结果表明:根际土壤中与非根际土壤中共检测出16种PAHs组分,非根际土中PAHs质量分数呈现21～40 cm41～60 cm0～20 cm的分布规律,而根际土中PAHs质量分数呈现21～40 cm0～20 cm41～60 cm的分布规律;根际土和非根际土中多环芳烃的总含量的最高值均在21～40 cm土层,平均值分别为2.622 9和2.292 6 mg.kg-1;2环和3环低分子量PAHs的迁移能力强于4～6环多环芳烃。     

浅谈盐碱地植树造林

通过对盐碱地的类型、特点和盐碱地造林作用的分析,提出了盐碱地植树造林的措施,对指导盐碱地植树造林颇有益处。     

毛竹鞭根根际与非根际土壤养分含量特征

以毛竹鞭根根际和非根际土壤为研究对象,研究不同生长期竹鞭根际与非根际土壤养分含量。结果表明:毛竹鞭根根际土壤p H值、水解氮、速效钾、有效磷含量明显高于非根际土壤,其中p H值平均提高0.82、水解氮含量平均提高111.63 mg/kg、有效磷含量平均提高0.57 mg/kg、速效钾含量平均提高92.33 mg/kg;毛竹鞭根根际与非根际土壤有效锌、有效铜、有效硼含量差异不显著。毛竹鞭根根际土壤水解氮和速效钾含量在不同生长期存在显著差异,表现为在行鞭期较高,在孕笋期和出笋期偏低。     

不同海拔毛竹土壤酶活性与土壤理化性质关系的研究

以江西省大岗山地区的毛竹林为研究对象,利用相关分析和主成分分析对不同海拔(300、400、500、600、700m)土壤纤维素酶、蔗糖酶、淀粉酶、β-葡糖苷酶和多酚氧化酶活性的变化特征进行了分析,探讨了其与土壤理化性质的关系。结果表明:土壤化学指标表现出随海拔的升高而增加的变化特征,除碱解氮外,其他各指标均处于较低水平,但物理指标的变化各不相同;随海拔升高,β-葡糖苷酶与多酚氧化酶活性呈现出增加的趋势,而纤维素酶、蔗糖酶和淀粉酶活性无明显变化规律;几种土壤酶对土壤肥力的指示效果不同,β-葡糖苷酶在评价毛竹林土壤肥力上具有重要指示效果,其后依次为蔗糖酶和多酚氧化酶、纤维素酶,但淀粉酶不适宜用来评价土壤肥力状况;通过主成分分析计算综合得分,不同海拔毛竹土壤肥力随海拔的升高而增加。     

Impact of tree species on soil carbon stocks and soil acidity in southern Sweden

Abstract

The impact of tree species on soil carbon stocks and acidity in southern Sweden was studied in a non-replicated plantation with monocultures of 67-year-old ash (Fraxinus excelsior L.), beech (Fagus silvatica L.), elm (Ulmus glabra Huds.), hornbeam (Carpinus betulus L.), Norway spruce (Picea abies L.) and oak (Quercus robur L.). The site was characterized by a cambisol on glacial till. Volume-determined soil samples were taken from the O-horizon and mineral soil layers to 20?cm. Soil organic carbon (SOC), total nitrogen (TN), pH (H₂O), cation-exchange capacity and base saturation at pH 7 and exchangeable calcium, magnesium, potassium and sodium ions were analysed in the soil fraction?<?2 mm. Root biomass (<5 mm in diameter) and its proportion in the forest floor and mineral soil varied between tree species. There was a vertical gradient under all species, with the highest concentrations of SOC, TN and base cations in the O-horizon and the lowest in the 10–20?cm layer. The tree species differed with respect to SOC, TN and soil acidity in the O-horizon and mineral soil. For SOC and TN, the range in the O-horizon was spruce?>?hornbeam?>?oak?>?beech?>?ash?>?elm. The pH in the O-horizon ranged in the order elm?>?ash?>?hornbeam?>?beech?>?oak?>?spruce. In the mineral soil, SOC and TN ranged in the order elm?>?oak?>?ash?=?hornbeam?>?spruce?>?beech, i.e. partly reversed, and pH ranged in the same order as for the O-horizon. It is suggested that spruce is the best option for fertile sites in southern Sweden if the aim is a high carbon sequestration rate, whereas elm, ash and hornbeam are the best solutions if the aim is a low soil acidification rate.     

Effect of soil air volume change on CH4 consumption in brown forest soil

The relationship between soil air volume and CH₄ consumption in brown forest soils was investigated. The CH₄ consumption was negatively affected when the soil air volume decreased in experiments carried out bothin situ and in the laboratory. A strong dependence of the CH₄ consumption on the soil air volume was found in the laboratory experiment. These results indicate the possibility that the soil air volume is the primary rate-limiting factor for the CH₄ consumption in forest soil. Thus our work suggests that the other factors by which CH₄ consumption might be affected should be examined under the same air volume condition in the soil. To obtain accurate data, we need to be careful not to change the air volume by trampling or disturbing during the measurement of the natural methane fluxin situ.     

Effects of plant roots on soil preferential pathways and soil matrix in forest ecosystems

To characterize effects of plant roots on preferential flow(PF),we measured root length density(RLD)and root biomass(RB) in Jiufeng National Forest Park,Beijing,China.Comparisons were made for RLD and RB between soil preferential pathways and soil matrices.RLD and RB declined with the increasing soil depth(0–10,10–20,20–30,30–40,40–50,50–60 cm) in all experimental plots.RLD was greater in soil preferential pathways than in the surrounding soil matrix and was 69.5,75.0 and72.2 % for plant roots of diameter(d) \1,1 \ d \ 3 and3 \ d \ 5 mm,respectively.Fine root systems had the most pivotal influence on soil preferential flow in this forest ecosystem.In all experimental plots,RB content was the sum of RB from soil preferential pathways and the soil matrix in each soil depth.With respect to 6 soil depth gradient(0–10,10–20,20–30,30–40,40–50,50–60 cm) in each plot,the number of soil depth gradient that RB content was greater in soil preferential pathways than in the soil matrix was characterized,and the proportion was68.2 % in all plots.     

不同类型用地水土流失的对比研究

采用设置径流场、集水区等观测方法，经2～3年研究，发现裸地的土壤侵蚀剧烈，坡耕地土壤侵蚀达中度以上，而有林地仅为微度或轻度侵蚀。裸地的地表径流量最大，其次是坡耕地，有林地地表径流量仅为坡耕地的13.8%，裸地的6.9%。影响地表径流量的主要因子是降雨量和降雨强度，蒸发量、间隔期有负效应。