本研究选取西乌珠穆沁旗巴彦胡舒苏木区域内不同围封年限(3a、5a、7a、10a)的草原作为研究对象,以未封育的草原为对照,通过野外调查结合室内分析,分析草原不同围封年限的植物组成和群落特征.结果表明:(1)随围封年限的增长,植物种总数持续增加,由未封育的17种增至26种;(2)植被高度、盖度和地上生物量都有所增加,围封10 a较未围封样地分别增加了110.63％、141.33％、743.81％;(3)随围封年限的增长,多年生草本植物的优势地位显著提高,1a生草本和半灌木的优势地位下降,围封5a后禾本科植物占据优势地位.围栏封育在短期内一定程度上有利于草原植被的恢复和群落结构的稳定.

为了解草原矿区土壤碳(C)、氮(N)、磷(P)含量及生态化学计量特征,以锡林浩特胜利煤田周围草原为研究对象,研究不同距离、不同方向土壤C、N、P含量及化学计量特征.结果表明:1)土壤有机碳、全氮、全磷含量在4.0 km处最高,碳磷比(C/P)、氮磷比(N/P)在4.0 km处最高,碳氮比(C/N)在0 km处最高;2)有机碳含量在东向最高,全氮含量在东向和北向最高,全磷含量在北向最高;3)土壤有机碳含量与全氮含量、全磷含量、碳氮比、碳磷比、氮磷比,全氮含量与全磷含量、碳磷比、氮磷比,碳氮比与碳磷比,碳磷比与氮磷比呈极显著正相关(P＜0.01);碳氮比与氮磷比呈显著负相关(P＜0.05).试验表明,土壤碳、氮、磷含量、碳磷比最高值出现在4.0 km处,碳氮比最高值出现在0 km处,而土壤中磷元素迁移速度较慢,因此推测露天开采煤炭形成的粉尘促进了无机碳的扩散和转换.

[Objective] The aim was to accurately and truly reflect the changes in structure and function of the desert steppe ecosystem in Inner Mongolia. [Method] The desert steppe in Damao Banner was taken as the object of study,the change of vegetation coverage,grassland produc-tivity and carrying capacity in recent more than 30 years was studied by using 3S technology. [Result] The coverage of grassland vegetation in Damao Banner was increased by 2% compared with in the initial period of 2000;the productivity of grassland in Damao Banner decreased from south to north,which was higher than that in 2003;the carrying capacity of Damao Banner grassland was increasing compared with the 1980s and in the initial period of 2000. [Conclusion] The result provides theoretical basis for Inner Mongolia to make up ecological management decision.

我国北方荒漠草原地区生态环境总体上具有结构简单、易受干扰、自我调节能力差等特点.因此,在全球气候变化的大背景下,由于农业与牧业之间的激烈竞争,加之区内气候波动、人类活动干扰等诸多因素,对荒漠草原地区的生态环境和结构产生了重大影响.为了能准确和真实的反映我国北方荒漠草原地区生态系统的结构和功能的变化,该文选定达茂旗为研究对象,通过对草地退化结构变化、草地等和级结构变化的研究,得出以下结论:(1)相比20世纪80年代达茂旗退化、沙化、盐渍化草地,以及重度退化和重度盐渍化草地相比20世纪80年代都有所减少;(2)达茂旗草地等级由低一级的草地向高一级的草地逐渐演变;(3)达茂旗草地质量相比20世纪80年代有所降低.

近年来剧烈的人类活动和自然因素变化致使生态系统退化,表现为草地植被退化、生物种类单一、土壤物理性质变差等.为了探讨内蒙古典型草地生态系统的结构和功能变化,以呼伦贝尔典型草原退牧还草工程区为研究对象,采用成对取样方法(围栏内-围栏外)对退牧还草工程区禁牧和休牧两种干扰方式下植被恢复过程中物种多样性、地上生物量、土壤容重和水分等的变化特征进行了研究,以期为草地的合理利用和管理提供理论依据.结果表明:(1)不同干扰方式对草地物种多样性和地上生物量有明显影响,物种的多样性指数和丰富度指数在禁牧区分别为1.73和7.59,在休牧区为1.47和5.70,全部表现为禁牧区>休牧区(P<0.05).地上生物量则相反,在禁牧区和休牧区分别为36.34 g·m-2和42.83 g·m-2,表现为禁牧区<休牧区;(2)不同干扰方式对草地土壤物理性状有明显影响,但不同指标对干扰方式的响应不同.禁牧有利于土壤含水量的积累,放牧导致土壤紧实、容重增加,同一土层深度土壤含水量表现为禁牧区>休牧区,例如0～10 cm处土壤含水量在禁牧区和休牧区分别为4.57％和2.80％,禁牧区显著高于休牧区(P<0.05);土壤容重则相反,表现为禁牧区<休牧区.综上所述,不同的生态工程措施对草原生态系统有明显影响,禁牧有利于维持较高的物种多样性和维持较好的土壤物理性质,休牧可提高草原生产力,退牧还草工程对恢复草原生态功能起到了积极的作用.

Fencing is one of the important means of restoration and reconstruction of degraded grassland,and has been widely used in grassland ecological restoration programs in China.This study monitored fenced and free-grazed grassland plots,to evaluate the impacts of fencing on community plant species composition,compo-sition of functional groups,species diversity,aboveground biomass,soil organic carbon (C)and total nitrogen (N)contents of degraded grassland.The plant species number in fenced plots (22 species)was greater than that in free-grazed plots (17 species).Community diversity (H ),richness (Pa ),evenness (J P )indices and aboveground biomass did not differ significantly between fenced and free-grazed plots (P >0.05).Importance <br> value (IV),percentage,aboveground biomass,H ,Pa and J P indices of shrubs,semi-shrubs (SS)and peren-nial forbs (PF)in fenced plots were higher than those in free-grazed plots (P <0.05).Aboveground biomass of perennial grasses (PG)was higher in fenced plots than in free-grazed plots (P <0.05).Importance value (IV), percentage,aboveground biomass,H ,Pa and J P indices of annual or biennial herbs (AB)were lower in fenced plots than in free-grazed plots (P <0.05).The percentage and aboveground biomass of ecological func-tional groups did not differ significantly between fenced plots and free-grazed plots (P >0.05).Soil organic C and total N content were not significantly different between fenced plots and free-grazed plots (P >0.05).The soil organic C and total N contents decreased significantly (P <0.05)with increasing soil depth,but the rate of decrease with depth was less in fenced plots than in free-grazed plots.

The impacts of three kinds of human disturbances, i.e., non-grazing, reseeding and free-grazing, on plant community characters, i.e., species composition, composition of functional groups, species diversity, and aboveground biomass, were studied in a typical steppe in Inner Mongolia, China. The results showed that different disturbances had significant impacts on the structure and diversity of plant functional groups. The number of plant species, aboveground biomass, community diversity, and richness indices were the highest in the non-grazing treatment, with the fi-gures of 22, 171.32 g·m-2, 1.46 and 5.7, respectively. The importance value (IV), percentage, aboveground biomass, diversity, richness, and evenness indices of shrub and sub-shrub, and perennial grasses were also the highest in the non-grazing treatment. In contrast, the IV, species percentage, aboveground biomass, diversity, and evenness indices of perennial forbs were the lowest in the non-grazing treatment. The aboveground biomass of mesophyte, C3 and C4 plants was the highe-st with the figures of 22.22, 143.35 and 27.97 g·m-2 respectively in the non-grazing treatment. The aboveground biomass of mesoxerophyte was highest (13.60 g·m-2), the species percentage of xerophyte was lowest (48.5%) and that of C4 plants was highest (28.8%) in the reseeding treatment. The species percentage of annual or biennial herbs was highest (12.3%), while that of mesophyte and C4 plants was lowest (17.0% and 20.9%) in the free-grazing treatment. The non-grazing treatment showed a beneficial effect for restoration of degraded grassland system.

该文主要利用科尔沁左翼后旗地区2008-2012年土地利用变更调查数据，进行了土地类型动态度分析，研究该地区土地利用变化，从而了解其动态变化特点。

该文以科尔沁左翼后旗为例，通过研究科尔沁左翼后旗城乡建设用地结构和布局，对其特征及原因进行了分析，进而提出城乡建设用地结构和布局优化对策。

本研究在原来CASA模型的基础上,对模型参数最大光能利用率和水分胁迫系数的算法进行了改进,利用改进后的CASA模型模拟了2010年内蒙古锡林郭勒盟草原植被净初级生产力(NPP),并用地面实测样方数据对改进后的模型进行精度验证.结果表明:改进的CASA模型可应用于内蒙古草原小尺度植被NPP的估测,模拟NPP值与地面实测值之间的相关性达到显著水平(R2=0.829,P＜0.05);2010年内蒙古锡林郭勒盟草原植被生长季(4-10月)NPP为284.64gC·m-2·a-1,不同地区年均NPP相差较大,东北部东乌珠穆沁旗草原NPP高达411.11 g C·m-2·a-1,而西北部的二连浩特市草原NPP仅为158.87 g C·m-2·a-1;整体上,锡林郭勒盟草原的NPP由东向西逐步递减,这与该区域水热条件限制基本一致;由于降水量的时滞效应,该年度内NPP出现两次峰值;2010年锡林郭勒境内草原NPP集中分布在250～350 g C·m-2·a-1,草甸草原的NPP最大,典型草原次之,荒漠草原最小.

To accurately understand the effect of“Grassland ecological protection and restoration program”and to provide effective scientific support for northern grassland's ecological protection and optimal management, a typical grassland of“Returning Grazing Land to Normal Grassland Project”was chosen as the research site for grassland condition monitoring. The integrating method of outdoor sampling (in-fence&out-fence) and indoor analyzing was used to analyze the impacts of three kinds of human interference, non-grazing, reseeding and free-grazing on soil density, soil moisture content, organic carbon and the total nitrogen content. The results showed that with the increase of soil layer from 0~30 cm, soil moisture, organic carbon and total nitrogen contents ranked in different treatments as reseeding>non-grazing>free-grazing (P<0.05);the soil density ranked as free-grazing>non-grazing>reseeding (P<0.05). With the increase of soil depth, the soil density showed no significant change (P<0.05), while soil organic carbon and total nitrogen contents decreased significantly (P<0.05);soil moisture content was opposite. The soil density was significantly negatively correlated to the soil moisture, soil organic carbon and total nitrogen contents at each layer (P<0.000 1), whereas the soil moisture , organic carbon and total nitrogen contents were positively correlated each other (P<0.000 1). To sum up, different treatments of interference got significant effects on the physical and chemical properties of the soil. Free-grazing accelerated the loss of the soil organic carbon and total nitrogen, while non-grazing and reseeding played an effective role in halting the grassland degradation and recovering grassland function.

Typical steppe of Inner Mongolia was chosen as the research site for grassland condition monitoring.The integrating method of outdoor sampling and indoor determination was used to analyze the correlation between soil or?ganic carbon(C)and soil physic-chemical properties.The results showed that the soil organic C was significantly pos?itively correlated to the soil total nitrogen and soil moisture content(P<0.01),while soil density was significantly negatively correlation with soil organic C(P<0.01).Soil total nitrogen was significantly positively correlated to the soil moisture content(P<0.01),and was significantly negatively correlation with soil density(P<0.01).The results also indicated that the nutrients in grassland ecosystem were organic whole of interrelationship and interaction.

Study on vegetation change of the degraded grasslands can provide knowledge on the restoration processes and mechanism,reveal the factors limiting restoration,and is further a base for making ecological measures for fast restoration with the lowest input.The natural restoration of a degraded grassland were researched in the desert steppe zone,Inner Mongolia.The results showed that,through eight years banning grazing,the height of grassland community greatly increased;and its coverage,biomass and species had an increase,but species had a decrease in banning grazing five years.The species diversity and community evenness had a marked increase at first,and then a decrease;species richness and ecological dominance had a complex wavy change,the reason of this change was the grassland feature and people actions.Early in the banning grazing,intrusion of some annual and biennial plants and restoration of dominant species made plants community feature had an increase.Banning grazing seven years later,structure of the community tends to be more stable.

Taking Pinus tabulaeformis,Platycladus orientalis,Robinia pseudoacacia and Ouercus liaotungensis forests in the same period in the Beijing low mountain area as a case,this paper studied evaluation on health conditions of different tree species and different standing forests for soil and water conservation.Through the construction of the evaluation system,the establishment of a comprehensive evaluation model,calculation of the stand comprehensive evaluation index,different forest stands were evaluated.Then the soil and water conservation forest was divided into four classes： the first class forests for soil and water conservation with comprehensive evaluation value of S≥8;the second class with 5≤S〈8;the third class with 2≤S〈5;the fourth class with S〈2.Then growth conditions and site characteristics of the different types of forest for soil and water conservation was discussed,and a reasonable improvement measures was proposed.