豆禾混播建植人工草地对牧草产量和草质的影响

以内蒙古锡林浩特内蒙古大学草地生态学研究基地为试验样地,通过对单播和混播情况下豆科牧草和禾本科牧草产量、竞争能力、牧草营养价值等测定分析,比较不同播种方式对牧草生长的影响。结果表明:豆禾混播情况下,牧草产量有较为明显的提高,尤其是第2年混播草地中禾本科牧草的产量较第1年有了提高。在豆禾播种比例1∶2的情况下,混播牧草在一定程度上避免了种间竞争,2 a内混播草地的相对产量总值均大于1,表明其生长较为协调,豆科和禾本科牧草双方均受益。豆禾混播时牧草的营养价值有所改变,豆禾混播草地粗蛋白含量增加,粗纤维含量下降,营养价值有所提高。因此,豆禾混播草地稳定性高,牧草产量和营养价值较高,有利于大面积推广,是建植人工草地的较好选择。     

近40年玛曲草地暖干化趋势及影响因子分析

通过利用Holdridge可能蒸散率(PER),对玛曲草地1971～2010年的干湿变化特征进行了分析,近40年玛曲草地PER呈明显的上升趋势,上升趋势达0.03/10a,20世纪90年代后,玛曲草地PER持续偏高,并在1993年出现了增大突变,降水量以7.4mm/10a的趋势减少,温度以0.46℃/10a的趋势上升,生物温度以0.25℃/10a的趋势上升,降水量与生物温度呈现出明显反向变化,玛曲草地有从极湿润区向湿润区过渡的趋势,出现了明显的暖干化趋势。主成分分析表明玛曲草地暖干化的主要原因是气温升高,同时日照时数增加、降水量减少、相对湿度下降和风速减小加剧了暖干化的趋势。受气候暖干化和人为因素的影响,玛曲草地出现了明显的退化和沙化,沼泽湿地的面积也呈明显的减少趋势,导致玛曲草地牧草产量下降,涵养水源能力急剧下降和生物多样性锐减。     

MERSI资料在内蒙古草原牧草产量估测中的应用研究

利用卫星遥感资料估测天然草地生产力是草地生态学和草地管理学的研究热点。内蒙古草原面积大、类型多、具有重要的生态和生产功能,实时监测其草地生产力变化十分必要。由于风云3号极轨气象卫星资料具有迅速、覆盖面广、不受地面条件限制等优点,文中将内蒙古自治区气象局42个生态监测站点2008～2010年6～8月份的风云3号卫星MERSI遥感数据和同步的牧草产量实测数据相结合,引入MERSI-NDVI概念,建立了基于MERSI-NDVI估测内蒙古草原牧草产量的估测模型,并对模型的可靠性进行了检验。结果表明:基于风云3号极轨气象卫星资料提取的MERSI-NDVI与内蒙古草原牧草产量具有较高的相关性,利用MERSI-NDVI遥感估测天然草地牧草产量是可行的;基于MERSI-NDVI构建的三个类型草地遥感估产模型精度在65.32%～88.84%之间,其精度可以满足宏观测产的要求。不仅适合大面积监测估产,还可用于局部地域牧草产量的定点估产。     

内蒙古地区与全球云水资源分布情况研究

利用ISCCP-D2云资料、内蒙古116个气象站地面降水资料、NCEP同化资料,分析研究了全球云水时空分布特征及内蒙古地区云水时空分布特征、降水分布特征,研究表明:20年年均变化来看,可降水量在波动过程中有增多的趋势;降水量从1984年到1998年有增多的趋势,1998年到2001年有明显的减少趋势;从24年实际降水量空间变化趋势来看,内蒙古东部地区有明显的减少趋势,中西部地区有增多趋势,尤其中部地区乌兰察布市、呼和浩特市、包头市等地区有明显的增多趋势。     

近40年内蒙古区域温度和降雨量变化的时空格局

在气候变化日益加剧的情形下,制定科学合理的气候变化应对策略,需要准确把握区域气候变化的时空特征与规律。文中以内蒙古为研究区域,分析了1969-2008年间区域温度和降雨量的年值和季节值变化趋势及时空格局,主要结论:1)年均温度明显升高,有54.82%地区累计升高1.6~2.4℃,有29.95%地区累计升高2.4~3.2℃,无降低区域,在空间上,温度升高区域主要集中在除阿拉善盟和鄂尔多斯市的大部分地区;从降雨量变化来看,63.05%区域变化在±1mm/a,27.58%地区40年来累计减少40mm以上,9.37%地区略有增加趋势,从空间上分析,降雨量减少地段主要集中在除阿拉善盟、鄂尔多斯市以及呼伦贝尔北4市旗之外的大部分地区。2)从季节日均温度、降雨量的变化来看,温度变化4个季节均以升高为主,增幅规律为春季冬季秋季夏季;降雨量增与减变化存在季节差异,春季有18.39%地段明显增多,而其它季节均以不同程度的减少为主,其中夏季减少最多,面积达35.86%。3)近40年来,温度变化存在明显的突变点,但是突变时间存在空间分异。4)总之,由于温度的明显升高和降雨量不同程度的减少,将驱使区域气候旱化程度增强,这将对农牧业生产带来不利影响,亟待制定科学有效的中长期应对方略。     

中国温带草地草畜平衡动态监测系统的研究

<正> 中国温带草地约350万平方公里,它是重要的放牧畜牧业基地,这里四季分明,草地季节动态明显,牧草生长呈单峰型;冬季漫长,枯草期达半年以上。由于年际间降水变率大,导致草地初级生产力上下波动,一般波动幅度达±15%以上,遇极端年份达±200%或更高。随着畜牧业的发展,放牧压力日增,导致大面积草地退化,生产力下降、草     

近10年甘南牧区草地净初级生产力变化研究

以改进的CASA模型为基础,结合MODIS NDVI数据、气象资料,估算了甘南牧区草地2000、2005、2008年牧草生长旺季7月净初级生产力,并分析了其时空动态.结果显示:(1)甘南牧区草地净初级生产力(NPP)的空间分布基本格局是西南偏西和东北两区域最低,然后由西南-东北方向为轴心逐渐向内陆中心部分递增,该分布规...     

脊萤叶甲的生物学特性及其防治

脊萤叶甲Theone silphoides (Dalman)是新疆荒漠草地的重要害虫。近年在新疆局部地区受害严重,并有逐年加重的趋势。该虫发生严重的地区蒿草叶片被食光,影响了畜牧业发展。蒿类植物在草地牧草产量的构成中比例大,在营养价值上如蛋白质含量超过禾本科牧草,特别是粗脂肪含量高于禾本科、豆科草类0.5～1倍,是家畜春季催乳、秋季抓瞟、冬季保膘的优良牧草;它还能抗旱、抗风沙,具有较强的固沙能力。有关脊萤叶甲的研究在国内外均未见报道。作者于1991～1995年进行了调查和防治试验,结果如下。     

2000-2010年内蒙古防沙带草地NPP的变化特征

利用CASA模型计算得到2000-2010年净初级生产力(NPP)及2000年与2010年30 m分辨率的土地利用/覆被数据,探讨近年来内蒙古防沙带草地NPP的变化特征及其与自然因素之间的关系.结果表明:①2000-2010年,研究区草地转为建设用地成为草地流失的主要因素,而荒漠成为草地增加的主要来源,水体与耕地成为草地增加的第二来源.②内蒙古防沙带草地NPP表现为“整体改善,局部退化”的态势.NPP明显增加区主要为海拔低于500 m的东部科尔沁地区与东南部的宁城县、建平县等区域.NPP降低区西至固阳县东至正蓝旗呈带状分布.③从模型的回归结果看,影响草地NPP降低因素的重要性排序为:高程(DEM)＞降水量＞气温＞草地初始质量.草地NPP增加与降低面积在海拔1000m与1300m左右时达到峰值,而这两个海拔高度又恰好是人类活动活跃区,说明草地NPP受人类活动的影响也非常明显.降雨量对草地NPP有明显的正面影响,而气温则表现为负面影响.     

若干牧草在宁夏盐池干旱风沙区的引种试验

从美国和中国引进若干牧草品种,在宁夏盐池干旱风沙区对其进行了适应性、生长状况和生产性能的比较试验,目的是筛选出适合当地种植的牧草品种。结果表明:豆科牧草以宁苜1号、中苜1号和沙打旺的适应性强,产量高,可作为该地区推广种植的优良牧草;草木樨产量最高但越冬率较低,可作为轮作用牧草;禾本科牧草以圆柱披碱草和蒙农杂种冰草适应性较强,且产量较高,可作为当地种植的优良禾草;扁穗冰草和中间冰草存活率较低,适应性及生产性能一般,需采取保护措施提高其存活率才可推广种植;白三叶、金皇后、细茎冰草和高羊茅适应性较差,不宜种植。     

Effects of climate change on phenology and primary productivity in the desert steppe of Inner Mongolia

 Variations in temperature and precipitation affect local ecosystems. Considerable spatial and temporal heterogeneity exists in arid ecosystems such as desert steppes. We analyzed the spatiotemporal dynamics of climate and vegetation phenology in the desert steppe of Inner Mongolia, China, using meteorological data from 11 stations (1961–2010) and phenology data from 6 ecological stations (2004–2012). We also estimated the gross primary production for the period of 1982–2009 and found that the annual mean temperature increased at a rate of 0.47ºC/decade during 1961–2010, with the last 10 years being consistently warmer than the 50-year mean. The most significant warming occurred in winters. Annual precipitation slightly decreased during the 50-year period, with summer precipitation experiencing the highest drop in the last 10 years, and spring precipitation, a rise. Spatially, annual precipitation increased significantly in the northeast and eastern central area of the region next to the typical steppe. From 2004 to 2012, vegetation green-up and senescence date advanced in the area, shortening the growing season. Consequently, the primary productivity of the desert steppe decreased along precipitation gradient from southeast to northwest. Temporally, productivity increased during the period of 1982–1999 and significantly decreased after 2000. Overall, the last decade witnessed the most dramatic climatic changes that were likely to negatively affect the desert steppe ecosystem. The decreased primary productivity, in particular, decreases ecosystem resilience and impairs the livelihood of local farmers and herdsmen.     

Topographical and hydrological effects on meso-scale vegetation in desert steppe,Mongolia

This study investigated the seasonal variations of the normalized difference vegetation index(NDVI) and its relationships with climatic variables and topography in a small-scale(20 km×20 km) area(i.e., Tsogt-Ovoo village) within the desert steppe zone of Mongolia using in-situ observed climate data and satellite remote sensing data. We found that the topography is very important for vegetation growth in the desert steppe although the summer precipitation is the constraining factor. The unexpectedly high NDVI(up to 0.56), as well as the high aboveground biomass, in the valley bottom was primarily resulted from the topography-modulated redistribution of overland flow after relatively heavy precipitation events during the growing season. This makes the valley bottoms in desert steppes not only reliable feeding resources for livestock but also heavens for wild lives. But, the detected large standard deviation of annual maximum NDVI(NDVI_(max)) from 2000 to 2013 in the valley bottom in response to rather variable precipitation implies that the valley bottoms under desert steppe climates are more vulnerable to climatic change.     

Spatiotemporal patterns of the forage-livestock balance in the Xilin Gol steppe,China:implications for sustainably utilizing grassland-ecosystem services

Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol steppe is an important native grassland resource in Inner Mongolia Autonomous Region,China.This study aimed to elucidate the dynamics of the forage-livestock balance in the Xilin Gol steppe during the period 2000–2015.We evaluated the forage production and corresponding livestock carrying capacity(LCC)in the growing seasons of 2000–2015 using remote sensing data and field surveys.The spatiotemporal patterns of the forage-livestock balance were then assessed at regional,city(including city,county and banner),and village scales using statistical and household survey data.The results showed that both forage production and LCC decreased in the Xilin Gol steppe from east to west.During the period 2000–2015,the regional average forage production and corresponding LCC fluctuated without following a distinct trend,but were consistent with the variations in precipitation.The forage-livestock balance varied with time,space,and scale.At the regional scale,steppes were overgrazed in the early 2000s,but a forage-livestock balance or even grazing potential was achieved in other years.At the city scale,approximately half of the region exhibited a"forage-livestock balance"since 2000.However,about half of the region still experienced overgrazing,which mainly located in the southwest sandy zones.Such changes may have been affected by the variations in grassland quality,forage production,compensation payment,and so on.We suggest a location-specific management scheme for grazing constraints,ecological compensation payment,and industry development to aid in harmonizing animal husbandry and environmental restoration,while promoting sustainable development goals by 2030.     

Spatiotemporal characteristics and influencing factors of ecosystem services in Central Asia

Land use/land cover (LULC) change and climate change are two major factors affecting the provision of ecosystem services which are closely related to human well-being. However, a clear understanding of the relationships between these two factors and ecosystem services in Central Asia is still lacking. This study aimed to comprehensively assess ecosystem services in Central Asia and analyze how they are impacted by changes in LULC and climate. The spatiotemporal patterns of three ecosystem services during the period of 2000-2015, namely the net primary productivity (NPP), water yield, and soil retention, were quantified and mapped by the Carnegie-Ames-Stanford Approach (CASA) model, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, and Revised Universal Soil Loss Equation (RUSLE). Scenarios were used to determine the relative importance and combined effect of LULC change and climate change on ecosystem services. Then, the relationships between climate factors (precipitation and temperature) and ecosystem services, as well as between LULC change and ecosystem services, were further discussed. The results showed that the high values of ecosystem services appeared in the southeast of Central Asia. Among the six biomes (alpine forest region (AFR), alpine meadow region (AMR), typical steppe region (TSR), desert steppe region (DSR), desert region (DR), and lake region (LR)), the values of ecosystem services followed the order of AFR>AMR>TSR>DSR> DR>LR. In addition, the values of ecosystem services fluctuated during the period of 2000-2015, with the most significant decreases observed in the southeast mountainous area and northwest of Central Asia. LULC change had a greater impact on the NPP, while climate change had a stronger influence on the water yield and soil retention. The combined LULC change and climate change exhibited a significant synergistic effect on ecosystem services in most of Central Asia. Moreover, ecosystem services were more strongly and positively correlated with precipitation than with temperature. The greening of desert areas and forest land expansion could improve ecosystem services, but unreasonable development of cropland and urbanization have had an adverse impact on ecosystem services. According to the results, ecological stability in Central Asia can be achieved through the natural vegetation protection, reasonable urbanization, and ecological agriculture development.     

天山北坡中段草地类型α多样性研究

定量比较天山北坡中段乌鲁木齐地区各草地植被垂直带中具代表性的16个主要草地类型的植物多样性指数、物种丰富度指数和均匀度指数。从各草地类型多样性指数大小来看,山地草甸>草甸草原>典型草原>荒漠草原>亚高山草甸>高寒草甸>荒漠。其中分布于山地草甸的鸭茅+草原老鹳草+杂类草的草地类型和草原老鹳草+杂类草+禾草的草地类型的物种多样性指数最大,而分布于荒漠带土质生境的散枝猪毛菜+角果藜的草地类型和小蓬草地类型的物种多样性指数最小。其结果反映了生境异质性沿着水、热生态梯度变化的规律;从草地物种多样性的角度,揭示了不同草地类型在组成、结构、功能和动态的差异;通过指数间相关关系的分析,探讨草地类型多样性与草地生产力的相互影响,可为该地区的生物多样性资源保护提供科学依据。     

围栏封育对新疆山地退化草原植物群落特征的影响

围栏封育作为一种有效的退化草原管理措施,近年来在我国退化草原恢复中得到极为广泛的应用。以新疆巴里坤县退化温性荒漠草原为研究对象,通过连续4 a围栏封育样地和自由放牧样地的植被调查资料,对比分析围栏封育样地和自由放牧样地的植被群落组成和地上生物量的动态特征。结果表明:(1)通过围栏封育措施,退化草原的物种多样性和群落生态优势度与自由放牧样地相比略有提高,群落均匀度略有降低,但通过t检验,差异均未达到显著水平(P0.05)。(2)随着封育措施的实施,总体上草原群落优势种为沙生针茅和伊犁绢蒿,反映出西部内陆半干旱地区温性荒漠草原特有的特征;自由放牧样地,沙生针茅和伊犁绢蒿在群落中的优势地位发生变化。(3)围栏封育措施提高了植物群落的平均高度、地上生物量。随着围封时间的延长,群落地上生物量增加,且显著高于自由放牧区,然而4 a围栏封育并不能使温性荒漠草原产草量达到最高水平,也不能使植物群落的多样性指标与自由放牧样地形成显著差异。     

Spatial and temporal variability in vegetation cover of Mongolia and its implications

In this paper, we attempted to determine the most stable or unstable regions of vegetation cover in Mongolia and their spatio-temporal dynamics using Terra/MODIS Normalized Difference Vegetation Index(NDVI) dataset, which had a 250-m spatial resolution and comprised 6 periods of 16-day composited temporal resolution data(from 10 June to 13 September) for summer seasons from 2000 to 2012. We also used precipitation data as well as biomass data from 12 meteorological stations located in 4 largest natural zones of Mongolia. Our study showed that taiga and forest steppe zones had relatively stable vegetation cover because of forest characteristics and relatively high precipitation. The highest coefficient of variation(CV) of vegetation cover occurred frequently in the steppe and desert steppe zones, mainly depending on variation of precipitation. Our results showed that spatial and temporal variability in vegetation cover(NDVI or plant biomass) of Mongolia was highly dependent on the amount, distribution and CV of precipitation. This suggests that the lowest inter-annual CV of NDVI can occur during wet periods of growing season or in high precipitation regions, while the highest inter-annual CV of NDVI can occur during dry periods and in low precipitation regions. Although the desert zone received less precipitation than other natural zones of the country, it had relatively low variation compared to the steppe and desert steppe, which could be attributed to the very sparse vegetation in the desert.     

利用强度对荒漠草原土壤氮循环系统的影响

随着气候的变化和人类的干扰,草原退化日趋严重。文中研究了内蒙古荒漠草原不同利用强度下土壤中4类氮素转化菌,以及土壤的固氮作用、氨化作用和硝化作用强度。结果表明,轻牧区土壤中4类氮素转化菌的数量显著增加（P〉0.05）,也显著加强了土壤中的固氮作用、氨化作用和硝化作用。有利于促进土壤的氮循环;重度利用则导致草原土壤中氮素...     

影响盐池县半荒漠风沙区草畜平衡的因素分析

本文全面论述了影响宁夏盐池半荒漠风沙区草畜不平衡的自然因素和人为因素，将为该区进行草畜资源平衡调控研究提供依据。