大安市L乡砖厂破坏水土植被案分析

大安市Ｌ乡砖厂破坏水土植被案分析吉林省水利厅王洪涛（案情简介）１９９３年初，大安市Ｄ乡林业大队群众Ｚ某和市Ｇ局在职干部Ｊ某会伙承包了Ｌ乡砖厂。砖厂开工后，未办理水土保持审批手续，任意取土，严重地破坏了自然地貌、植被，造成大面积的水土流失。（案件处理情...

黄河流域砒砂岩区典型水土保持植被生长特征及限制因素研究

以内蒙古砒砂岩区鲍家沟小流域为研究区,以该流域典型水土保持植被为研究对象,探究水土保持植被的生长特征及其限制性因子。结果表明:1)砒砂岩区典型小流域的水土保持植被种类相对单一,沙棘和柠条林生长发育状态相对稳定,油松,山杏林的生长发育状态受立地条件影响较大;2)各林地土壤有机质含量在2.45~6.23 g·kg^(-1),土壤容重在1.51~1.71 g·cm^(-3),土壤含水率在10%~18%,研究区土壤紧实,肥力条件较差;3)通径分析的结果表明,土壤有机质为限制砒砂岩区人工林生长发育的直接限制性因子,坡度和坡向因子为间接限制性因子。研究砒砂岩区水土保持植被的生长发育特征,建立其生长特征与环境因子的联系,对于深入解读生态恢复过程,减轻入黄泥沙有重要意义。

不同配置的多功能水土保持植被对黑土抗侵蚀特征的影响

以2014年在黑龙江省拜泉县(125°30′~126°31′E,47°20′~47°55′N)建立的“银中杨(Populus alba×P.berolinensis)+东风菜(Aster scaber)”、“银中杨+大叶芹(Pimpinella brachycarpa)”、“银中杨+老山芹(Ostericum sieboldii)”、“银中杨+龙牙楤木(Aralia elata)”4种配置的多功能水土保持植被样地土壤为研究对象,以传统水土保持植被银中杨纯林林地土壤为对照,以表层(0~10 cm)土壤粒径大于1.0 mm水稳性团聚体质量分数、平均质量直径、分形维数、水稳性指数、抗冲系数为评价指标,分析配置的多功能水土保持植被对黑土土壤抗侵蚀特征的影响。结果表明:与银中杨纯林相比,配置的“银中杨+东风菜”、“银中杨+大叶芹”2种多功能水土保持植被,不仅显著增加了土壤粒径大于1.0 mm水稳性团聚体质量分数、平均质量直径、水稳性指数,而且显著降低了团聚体分形维数(P<0.05);配置的“银中杨+老山芹”多功能水土保持植被,显著增加了土壤粒径大于1.0 mm水稳性团聚体质量分数、平均质量直径、水稳性指数(P<0.05);配置的“银中杨+龙牙楤木”多功能水土保持植被,仅显著增加了土壤水稳性指数(P<0.05)。配置的4种多功能水土保持植被土壤的抗冲系数,虽然与银中杨纯林相比均有所增加,但仅“银中杨+东风菜”土壤的抗冲系数显著提高(P<0.05)。综合研究结果表明,土壤的抗蚀性,是多功能水土保持植被对土壤抗侵蚀特征影响的主要评价指标;配置的“银中杨+东风菜”多功能水土保持植被,同时提高了土壤抗蚀性、抗冲性,具有较强的增强土壤抗侵蚀的能力。

岩溶石漠化综合治理水-土-植被关键技术分析

结合岩溶石漠化问题,分析综合治理技术,在具体研究中,以项目背景为出发点,分析项目所在地自然生态情况与问题,并提出治理重点和关键技术。本次治理的重点是红水河与左右江流域地区,有关人员通过改良土质、加快成土速度、重视自然恢复等多种技术手段,使该流域地区岩溶石漠化问题得到解决。另外,综合治理过程中,还应做好植被种类选择、采取种间配置方案,在保证治理效果的前提下,为同类项目积累宝贵经验。

不同水土保持植被对典型黑土微团聚体稳定性的影响

以典型黑土区落叶松人工林、水曲柳人工林和草地等水土保持植被以及耕地土壤为研究对象,通过土壤微团聚体分散系数、粒径组成以及不同粒径微团聚体有机碳质量分数的测定计算和分析。结果表明:(1)与耕地相比,所研究的3种水土保持植被均可显著增加(0.05mm<d≤0.25mm)大粒径微团聚体组成比例、降低(d≤0.002mm)小粒径微团聚体组成比例(P<0.05),并表现出乔木植被对增加土壤大粒径微团聚体比例的作用显著强于草地植被(P<0.05);(2)所研究的3种水土保持植被总体上均不同程度地较耕地增加了土壤微团聚体有机碳质量分数,尤其是乔木植被显著增加了土壤中各个粒径的微团聚体有机碳质量分数,且增加幅度显著高于草地植被(P<0.05);(3)水土保持植被均显著降低了土壤分散系数(P<0.05)。可以认为,水土保持植被通过改善土壤微结构和增加微团聚体有机碳质量分数,进而实现增强微团聚体的稳定性,以微团聚体有机碳质量分数增加的贡献大于微团聚体组成的改变。

城市湿地公园建设中水土保持的对策探究

伴随着我国城市化进程的加快,在很大程度上促使我国的城市湿地面积迅速缩减,在一定程度上造成湿地的社会生态效益受到极大的侵害。随着人们对环境保护和生态恢复意识的增强,国家和政府开始对城市湿地公园的建设更加重视,加大了城市湿地的建设、功能的恢复与保护力度。公园建设过程中,保持水土及维护土壤活力是关乎景观生态可持续性的一项关键因素,主要对建设过程中水土保持的方式方法进行探讨,旨在为更好地建设湿地公园作贡献。

青海高原湿地特征及其保护

青海省地处青藏高原东北部 ,是我国长江、黄河和澜沧江的发源地 ,素有“江河源”之称 .青海高原湿地类型包括自然湿地和人工湿地两大类型 ,湿地总面积约 5 5 6 6 2 .7km2 ,占全省土地总面积的7 7% .高原湿地分布特点主要表现为 3种形式 :1)以湖泊或浅塘为中心的环带状分布 ;2 )以河流为中心的条带状分布 ;3)河源区的斑块状镶嵌分布 .高原湿地生物种类较为丰富 ,有湿地种子植物约 4 2 8种 ;湿地动物约 15 1种 ,其中鸟类约 73种、鱼类约 5 5种、哺乳类约 14种以及两栖类 9种 .湿地植被有水生植被、沼泽植被和沼泽草甸 3大基本类型 .近几十年来 ,青海高原湿地出现湖泊水位下降、湖泊面积萎缩、河流出现断流以及沼泽湿地退化等方面的明显变化 .鉴于高原湿地的生态功能和作用 。

Effect of Different Vegetation Types on Soil Erosion by Water

The C factor in Universal Soil loss Equation reflecting the effect of vegetation on soil erosion by water is one of the important parameters for estimating soil erosion rate and selecting appropriate land use patterns. In this study, the C factor for nine types of grassland and woodland was estimated from 195 plot-year observation data of six groups of soil erosion experiments on Loess Plateau. The result indicates that the effects of woodland and grassland on soil erosion keep approximately uniform after two or three years' growth. The estimated woodland C factor ranges from 0.004 to 0.164, and the grassland C factor ranges from 0.071 to 0.377, showing that the effect of woodland and grassland on soil conservation is greatly better than that of cropland. The study results can be used to compare or estimate the soil loss from land with different vegetation cover, and are the useful references for land use pattern selection and the project of returning cropland to forest or grassland.

Effect of Typical Vegetation Restoration Pattern on Soil and Water Conservation in Yuanmou Dry-hot Valley of Yunnan Province

In Yuanmou dry-hot valley of Yunnan Province,three typical vegetation restoration patterns including production forest transformed from sloping fields to terracing,ecological afforestation within the gully and ecological aforestation in gully head and slope were selected to compare their effects on soil and water conservation.Soil and water loss,soil infiltration rate and the soil moisture dynamics of soil profile with the depth of 0-100 cm of these three patterns and their controls were observed by established standard observation plots in rainy season.The results showed that the soil and water loss of ecological afforestation and production forest terrace reduced by over 30% and 60% compared with their controls（without growth of any vegetation）respectively,showing significant control effect on the soil and water loss.Vegetation restoration also apparently increased the infiltration rate of soil（increased by 100%-200%）.In rainy season,the soil moisture content of ecological afforestation and production forest terrace increased by over 30% and 100% compared with their controls.This indicated that vegetation restoration will not lead to soil aridity during the rainy season;vegetation restoration not only reduced the loss of surface water and soil fine particles,but also enhanced the infiltration of precipitation.These two effects made the soil moisture content increase throughout the profile.

Effect of Vegetation Changes on Soil Erosion on the Loess Plateau

Vegetation is one of the key factors affecting soil erosion on the Loess Plateau. The effects of vegetation destruction and vegetation restoration on soil erosion were quantified using data from long-term field runoff plots established on the eastern slope of the Ziwuling secondary forest region, China and a field survey. The results showed that before the secondary vegetation restoration period (before about 1866-1872), soil erosion in the Ziwuling region of the Loess Plateau was similar to the current erosion conditions in neighboring regions, where the soil erosion rate now is 8000 to 10000 t km-2 year-1. After the secondary vegetation restoration, soil erosion was very low; influences of rainfall and slope gradient on soil erosion were small; the vegetation effect on soil erosion was predominant; shallow gully and gully erosion ceased; and sediment deposition occurred in shallow gully and gully channels. In modern times when human activities destroyed secondary forests, soil erosion increased markedly, and erosion rates in the deforested lands reached 10000 to 24000 t km-2 year-1, which was 797 to 1682 times greater than those in the forested land prior to deforestation. Rainfall intensity and landform greatly affected the soil erosion process after deforestation. These results showed that accelerated erosion caused by vegetation destruction played a key role in soil degradation and eco-environmental deterioration in deforested regions.

Degradation of Wetlands on the Qinghai-Tibet Plateau:A Comparison of the Effectiveness of Three Indicators

The Qinghai-Tibet Plateau encompasses a large quantity of wetlands, some of which have been degraded to varying severity levels. In the literature, a number of degradation indicators have been proposed to evaluate ecological health of wetlands, but their effectiveness in the plateau environment remains unknown. In this study, we assessed the effectiveness of three degradation indicators, soil moisture content at lo em deep, vegetative cover, and density of pika burrows. The degradation severity of wetlands in Maduo County on the Qinghai-Tibet Plateau is enumerated at four levels, intact, slight, moderate and severe. Analysis of xo6 samples collected in the field demonstrates that the density of pika burrows is the least reliable indicator. By comparison, vegetative cover and underlying soil moisture content are more reliable, even though neither is a perfect indicator as the difference among adjacent levels of severity as revealed by t-test is not always statistically significant. The imperfection of vegetative cover as an indicator is due to its variation among different types of wetlands. The limitation of moisture content is attributed to its non-linear relationship with wetland degradation. Above the threshold of about 50% in moisture content wetlands are unlikely to be degraded. It is recommended that moisture be measured at the point near the surface and vegetative cover be further differentiated by species in order to improve their effectiveness.

Effects of fire disturbance on forest hydrology

Fire is quite a common natural phenomenon closely related to forest hydrology in forest ecosystem. The influence of fire on water is indirectly manifested in that the post fire changes of vegetation, ground cover, soil and environment affect water cycle, water quality and aquatic lives. The effect varies depending upon fire severity and frequency. Light wildland fires or prescribed burnings do not affect hydrology regime significantly but frequent burnings or intense fires can cause changes in hydrology regime similar to that caused clear cutting.

Vegetation/Soil Synthesis Water Index Using MODIS Data

In consideration of the spectral character of MODIS (Moderate Resolution Imaging Spectroradiometer) dataand the reflective spectrum of vegetation and soil, NDVI (Normalized Difference Vegetation Index) and NDWI (Nor-malized Difference Water Index) are deduced using one visible band (0.66μm) and two near-infrared bands (0.86μm,1.24 μm). Vegetation canopy temperature is derived using two thermal infrared bands (8.6 μm and 11μm). Then thevegetation/soil synthesis water index (VSWI) is acquired through analyzing the coupling character of three indexeswhich can reflect the water condition of vegetation. Finally, the synthesis index is verified by equivalent water contentof a single leaf. The matching results show that the synthesis index is directly proportional to the modeled data,which means that the vegetation water content can be reflected using the synthesis index effectively.

Effects of Water-table Depth and Soil Moisture on Plant Biomass, Diversity, and Distribution at a Seasonally Flooded Wetland of Poyang Lake, China

Hydrological regime has been widely recognized as one of the major forces determining vegetation distribution in seasonally flooded wetland. Poyang Lake, the largest freshwater lake in China, has been encountering dramatic changes in hydrological conditions in last decade, which greatly influenced the wetland vegetations. To explore the relationships between hydrology and vegetation distri- bution, water-table depth, soil moisture, species composition, diversity and biomass were measured at a seasonally flooded wetland section at Wucheng National Nature Reserve. Three plant communities, Artemisia capillaris, Phragmites australis and Carex cineras- cens communities, were examined which are zonally distributed from upland to lakeshore with decreasing elevation. Canonical corre- spondence analysis （CCA）, spearmen correlation and logistic regression were adopted to analyze the relationships between vegetation characteristics and hydrological variables of water-table depth and soil moisture. Results show that significant hydrological gradient exist along the wetland transect. Water-table demonstrates a seasonal variation and is consistently deepest in A. capillaris community （ranging from q）.5 m above ground to ＋10.3 m below ground）, intermediate in P. australis community （-2.6 m to ＋7.8 m） and shallow- est in C. cinerascens community （-4.5 m to ＋6.1 m）. Soil moisture is lowest and most variable in A. capillaris community, highest and least variable in P. australis community, and intermediate and moderate variable in C. cinerascens community. The CCA ordination indicated that variables of water-table depth and soil moisture are strongly related to community distribution, which explained 81.7% of the vegetation variations. Species diversity indices are significantly positively correlated with soil moisture and negatively correlated with moisture variability, while above- and belowground biomass are positively correlated with moisture. Above- and belowground biomass present Gaussian models along the gradient of average water-table depth in growing season, while species diversity indices show bimodal patterns. The optimal average water-table depths for above- and belowground biomass are 0.8 m and 0.5 m, respectively, and are 2.2 m and 2.4 m for species richness and Shannon-Wiener indices, respectively. Outcomes of this work improved the under- standings of the relationship between hydrology and vegetation.

Soil Organic Matter Fractions under Different Vegetation Types in Permafrost Regions along the Qinghai-Tibet Highway, North of Kunlun Mountains, China

As a key attribute of soil quality, soil organic matter(SOM) and its different fractions play an important role in regulating soil nutrient cycling and soil properties.This study evaluated the soil carbon(C) and nitrogen(N) concentrations in different SOM fractions(light– and heavy fractions,microbial biomass) under different vegetation types and analyzed their influencing factors in continuous permafrost regions along the Qinghai-Tibet Highway in the North of Kunlun Mountains, China.Soil samples were collected in pits under four vegetation types — Alpine swamp meadow(ASM), Alpine meadow(AM), Alpine steppe(AS) and Alpine desert(AD) — at the depth of 0-50 cm.The vegetation coverage was the highest at ASM and AM, followed byAS and AD.The results indicated that the concentrations of light fraction carbon(LFC) and nitrogen(LFN), and microbial biomass carbon(MBC)and nitrogen(MBN) decreased as follows: ASM > AM >AS > AD, with the relatively stronger decrease of LFC,whereas the heavy fraction carbon(HFC) and nitrogen(HFN) concentrations were lower in AS soils than in the AD soils.The relatively higher proportions of LFC/SOC and MBC/SOC in the 0-10 cm depth under the ASM soils are mainly resulted from its higher substrate input and soil moisture content.Correlation analysis demonstrated that aboveground biomass, soil moisture content, soil organic carbon(SOC) and total nitrogen(TN) positively correlated to LFC, LFN, HFC, HFN, MBC and MBN, while p H negatively correlated to LFC, LFN, HFC, HFN, MBC and MBN.There was no relationship between active layer thickness and SOM fractions, except for the LFC.Results suggested that vegetation cover, soil moisture content, and SOC and TN concentrations were significantly correlated with the amount and availability of SOM fractions, while permafrost had less impact on SOM fractions in permafrost regions of the central Qinghai–Tibet Plateau.

Variation of Soil and Water Volumes in Riparian Jungle Soils of Brazil

The objective of this work is to study the relation between humidity, density, porosity and shrinkage of the floodplain soil and riparian vegetation and their ability to store water. For this purpose, two locations for every type of soils were evaluated. Both were placed at the Agronomy University （Faculdade de Cidncias Agron6micas） in SAo Manuel, State of SAo Paulo, Brazil. The floodplain soil was vegetated with Southern Cattail （Typha domingensis）. In both places, soil samples were collected from several depths： 0, 30, 60 and 100 cm. Results show that lower soil density values （0.15 g/cm3） with organic texture and high porosities values （up to 86.2%） were found in samples with the highest organic material content in the floodplain soil. For this field experiment, flood plains soils （characterised as basin gley soils） presented high volumetric instability with a retratibility of 67.49% and higher water storage capacities compared to riparian stands soils （characterised as fluvic neosoils）.

对阴山北麓地区水土保持植被建设的经济播种量的研究

文章对阴山北麓地区不同播种量对牧草生长速度、植被盖度、生物量进行了研究。

Adopting A.pintoi as Live Mulch for Peach Orchards in China:Benefits of Soil and Water Conservation and Comprehensive Eco-service

Soil erosion occurred in orchards has often attracted extensive attentions from the society with environmental considerations,as orchard is one of major methods of agricultural production in China.In the hilly red soil region of China,many orchards are established on slope lands with a lack of grass covers,leading to severe soil losses.In order to mitigate this common environmental problem and evaluate the efficiency of erosion-control approaches,four treatments were set in field plots in this study,including terraced peach orchard with Arachis pintoi cv.Amarillo as mulch and Paspalum natatu and Digitariasmutsii as hedgerows(TTM),terraced peach orchard without conservation measures(TTW),sloping peach orchard with A.pintoi as mulch and P.natatu and Digitariasmutsii as hedgerows(STM),and sloping peach orchard without conservation measures(STW).The surface runoff,sediment yields and the contents of soil nutrients and organic carbon were monitored in the four treatments and the comprehensive eco-service benefits were further evaluated.The results indicate that available phosphorus(AP),available potassium(AK),total nitrogen(TN) and organic matter(OM) in the soils of the TTM treatments and STM were significantly higher than those of the treatments TTW and STW,suggesting positive effects of the vegetation covers on the soil nutrients.Mean annual surface runoff and coefficient ranged from 0.86 to 34.79 m^3,and 0.007 to 0.282,respectively;the treatment TTM exhibited the best water conservation benefits and the treatment STW was the worst.Soil erosion modulus of the plots were 0-28.76t/hm^2 per year in average,and the treatments TTM and STM reduced significantly soil loss in comparison of the treatments TTW and STW;(d) total organic carbon in the vegetation covers ranged from 130.23 to 195.93 kg per year,and that for TTM and STM treatment significantly higher than TTW and STW treatment;comprehensive eco-service values of the orchards were evaluated considering all the factors including water conservation,soil fertility conservation,CO_2 fixation and O_2 supply,ranging from 563.35 $/y to 765.51 $/y.As expected,the treatments TTM and STM had significantly greater eco-service values than the treatments TTW and STW.In summary,we concluded that terraced orchard with A.pintoi as live mulch plus Paspalum natatu and Digitariasmutsii as hedgerows is a highly sustainable land use practice for the slope lands in red soil hilly region of China.

The Relationship Between Vegetation Characteristics and Altitudes in Transitional Permafrost Zone in Xidatan, Qinghai-Tibetan Plateau

Many studies showed that permafrost has profound influence on alpine ecosystem. However, former researches were mainly focused on typical points by temporal scales. There were few studies about the correlation between vegetation characteristics and different altitudes covering a large region in spatial pattern, especially in transitional permafrost(TP). There were continuous permafrost(CP) discontinuous permafrost(DCP) and seasonal frozen ground(SFG) in this study region. The types of permafrost changed from SFG to DCP, and finally become CP as the altitudes of Xidatan increase. In this paper, 112 845 points interpreted by HJ1-B(environment and disaster monitoring and prediction small satellite constellation), vegetation investigation points, thawing layer thickness research sites, ground temperature and water content observation plots were used to examine the spatial pattern of vegetation which were located in different altitudes in Xidatan, a typical TP region, in Qinghai-Tibetan Plateau. Vegetation characteristics, soil moisture content(SMC) and thaw depths were collected in 15 August to 25 August2012. Characteristics of vegetation were mainly represented by fractional vegetation cover(FVC) derived from the normalized difference vegetation index(NDVI), as well as above ground biomass(AGB). In this paper, we analyzed that the distinction of vegetation characteristics in each range through statistics data. These ranges were divided by varied altitudes. For examples, the ranges were divided into 50 m or 100 m. In this study we use a large area plots method to further discuss the relationship between the features of vegetation and the different regions of permafrost based on altitudes shifts in Xidatan. A diagram described the vegetation characteristics variability with rising altitudes in transitional permafrost region was drawn in this paper. Our results illustrated the FVCs first increased in SFG region and then decreased in DCP zone slowly, and in CP region FVCs soared then dropped dramatically. With the altitudes increased, the curve of FVCs indicated a parabolic distribution except a little difference in the first 200 m range.

Water Yield of Xitiaoxi River Basin Based on InVEST Modeling

Water yield calculation and mapping are of great importance to water resource planning and management and hydropower station construction. A water yield model based on InVEST was employed to estimate water runoff in the Xitiaoxi River basin. The data included land use and land cover, average annual precipitation and potential evapotranspiration, soil depth, and plant available water content. In order to test model accuracy the natural runoff of Xitiaoxi River was estimated based on linear regression relation of rainfall-runoff in a ‘reference period’. After repeated validation, when the Z value was 6.5 the water yield was 8.30 E＋8 m3 and this was a smaller difference with natural runoff. From the distribution of water yield, south and southwestern areas of the watershed had higher water yield volumes per hectare.