同仁县天然草地产草量调查报告

为核定草地载畜量,合理保护草地资源,实行草畜平衡,根据农业部草地资源监测新标准,利用典型抽样的方法,2004年对同仁县草地资源进行了监测。结果表明:2004年草地可食鲜草产量为3 065.8kg/hm2,超载7.4万个羊单位,超载率24.1%,牲畜超载较严重。     

尖扎县天然草地产草量地面监测报告

根据农业部草原监理中心《全国草原监测实施方案》和《青海省草地资源与生态监测实施方案》的要求,对尖扎县草地资源进行了监测。结果表明,2008年草地可食鲜草产量2048.49kg/hm2,草地理论载畜量为17.78万羊单位,草地现有载畜量为52.94万羊单位,超载35.16万羊单位,超载率为50.56%。     

青海省共和县2005年草地产草量监测报告

通过对共和县天然草地产草量的监测,2005年共和县天然草地饲草量达72 614.60万千克,理论载畜量为1410580个羊单位,现有载畜量为1344 077个羊单位.经畜草平衡分析表明:全县草畜基本达到动态平衡,但各乡草畜不平衡状态仍很突出.除廿地乡超载率达到24.53%以外.其余各乡饲草资源尚有盈余或有不同程度的超载.     

海南州天然草地产草量地面监测报告

监测结果表明，海南州天然草地产草量１９９７年、１９９８年属正常年范畴。经草畜平衡分析，１９９８年全州草地理论载畜量为５０１．８６万羊单位，草地现有载畜量为５１４．７７万羊单位，草地牲畜的超载量为１２．９１万羊单位．超载率为２．５７％．草地生产基本实现了草畜平衡。     

同仁县草地产草量动态监测报告

利用典型抽样的方法 ,对同仁县天然草地进行了 5年监测。结果表明 :1 996年、1 997年全县草地产草量较高 ,草畜基本平衡 ;1 998年、1 999年、2 0 0 0年为欠年 ,草地产量明显下降 ,草地超载严重 ,尤其是2 0 0 0年草畜矛盾尤为突出 ,其超载率达 60 %以上     

2006年尖扎县尖扎滩乡冬春草地资源监测结果分析

根据农业部草地资源监测新标准,利用典型抽样的方法,对2006年尖扎县尖扎滩乡冬春草地资源进行了监测。结果表明:2006年该地区冬春草地可食鲜草产量为6 610.9万千克,超载13.28万个羊单位,牲畜超载十分严重。     

同仁县草地资源监测及草畜平衡分析

利用典型抽样的方法,对同仁县天然草地进行了5年监测。结果表明:2000年、2003年全县草地草畜基本平衡;2001年、2002年、2004年草地出现不同程度的超载,尤其是2004年草畜矛盾尤为突出,其超载率达60%以上。     

2006年尖扎县尖扎滩乡冬春草地资源监测结果分析

根据农业部草地资源监测新标准，利用典型抽样的方法，对2006年尖扎县尖扎滩乡冬春草地资源进行了监测。结果表明：2006年该地区冬春草地可食鲜草产量为6610．9万千克，超载13．28万个羊单位，牲畜超载十分严重。     

同仁县草地资源监测及草畜平衡分析

利用典型抽样的方法，对同仁县天然草地进行了5年监测。结果表明：2000年、2003年全县草地草畜基本平衡；2001年、2002年、2004年草地出现不同程度的超载，尤其是2004年草畜矛盾尤为突出，其超载率达60％以上。     

湟中县天然草地产草量及载畜量调查

通过草地产草量的调查和测定,测出理论栽畜量,通过草畜平衡分析,2006年湟中县草地理论载畜量为47.163 4万个羊单位,全县实际载畜量达62.23万个羊单位,超载15.066 6万个羊单位,超载严重.     

草原补奖政策下牧户是否超载？谁在超载及影响因素——以内蒙古为例

本文以内蒙古自治区草甸草原、典型草原、荒漠草原、沙地草原、草原化荒漠草地的15个旗县791户牧户为调查样本，以可持续生计资本为视角，通过建立二元Logit模型和多元线性回归模型，分析第一轮草原生态补奖政策实施期结束后，牧民草场是否超载?超载牧户的特征是什么?超载的程度如何?调查结果表明：内蒙古自治区第一轮草原生态补奖政策实施结束后牧户草场超载率平均值为44.70%；牧户草场超载率与草场经营规模呈负向相关关系，其超载率由高到低依次为小牧户 > 中牧户 > 大牧户；牧户草场超载率与畜牧业生产依赖程度呈负向相关关系，其超载率由高到低依次为纯牧户 > 兼牧户 > 非牧户；草场经营面积、冬季牲畜和固定资产数量成为影响牧户草场超载行为的关键生计指标，牧户草场经营面积对其呈显著负向影响，冬季家畜和固定资产数量对其呈显著正向影响。综上，第一轮草原生态补奖政策实施结束后牧户草场超载现象依然存在，超载率与草场资源占有率呈负向关系，与其对草原的依赖程度呈正向关系。     

放牧生态系统中的组织物质循环及其在牧场管理中的应用

综述了组织物质循环的理论及其在牧场管理中的应用。放牧过程中牧地草丛内的物流和能流循环是维持放牧生态系统平衡的重要基础,进行牧地草丛中植物组织循环,特别是其生长和萎蔫死亡的动态分析,为草地的有效利用提供了理论依据。文中对于牧地草丛内及刈牧过程中的组织物质循环,连续放牧及间断放牧条件下的组织物质循环进行了重点分析论述。建议在中国各类型草地上应用组织物质循环理论开展放牧管理研究,以推动草地管理理论和实践的发展。     

Plant and sward response to patch grazing in the Highland Sourveld

Abstract

Selective grazing by livestock inevitably results in patch grazing. This study was initiated to determine the effects of patch grazing on (1) the vigour of a single grass species, Themeda triandra, and of the sward, and (2) sward species composition. The generally held idea that a full season's rest followed by an early spring burn would prevent preferential grazing of patch grazed areas which had developed in the seasons before the rest was also tested. The vigour of 71 triandra was estimated from etiolated growth of marked tufts while sward vigour was indexed by above‐ground herbage production (AGHP). Etiolated growth of T. triandra and AGHP of the sward within patches were negatively affected by three seasons of grazing, but a full season's rest appeared sufficient to restore both the etiolated growth of T. triandra and the AGHP of the sward to a level similar to that in the non‐patches. A full season's rest followed by spring burning did not, however, prevent preferential grazing of grazed patches which had developed in the seasons prior to the rest. Species composition within patches (characterised by Increaser II species) differed significantly from the species composition of non‐patches (characterised by Increaser I species). Patch grazing may therefore initiate the rangeland degradation process in Highland Sourveld and patch grazing may be the focus from which rangeland degradation proceeds.     

The role of grazing in creating suitable sward structures for breeding waders in agricultural landscapes

French wet grasslands support important populations of lapwings and other waders. Grazing management is a key issue in the use of grasslands by these birds since they are very sensitive to sward structure (height and heterogeneity). To assess the impact of different grazing regimes on sward structure during spring, sward height was repeatedly measured in a coastal marsh for 2 years. Sward structure was characterised by variables related to height classes and an index of heterogeneity. Grazing regimes were described by stocking rates per period and N fertilisation level. Heterogeneity index was quadratically related to mean sward height both years. Four types of sward structures were characterised through principal component analysis. Co-inertia analysis showed a strong relationship between grazing regimes and sward structure. However, during spring, the relationship between stocking rate and sward structure differed according to year, impact of grazing being greater during drought year. Suitable sward structures were observed for both lapwings and redshanks. Wader habitat management through grazing calls for more attention to be paid to the delayed effects of autumn and winter grazing regimes. Sward heterogeneity emerges as a new characteristic to control, because it may introduce new constraints for livestock production.     

补播和划破草皮对退化亚高山草甸植被恢复的影响

在甘肃省甘南州临潭县研究围栏内补播和划破草皮对退化亚高山草甸植被的高度、总盖度、地上生物量和功能群物种多样性总指数的影响。结果表明,在各划破草皮处理中,牧草总盖度、地上生物量和功能群物种多样性总指数随着补播量的增加而增加,植被高度随着补播量的增加呈先增加后降低的趋势。补播和划破草皮有显著互作效果,补播量3[垂穗披碱草(Elymus nutans)播量为49.1 kg·hm-2,老芒麦(Elymus sibiricus) 播量为67.5 kg·hm-2,紫花苜蓿甘农1号(Medicago sativa cv.Gannong No.1)播量为23.3 kg·hm-2]和划破草皮组合的牧草地上生物量(201.5 g·m-2)、总盖度(88.2%)和功能群物种多样性总指数(1.203)达到最大值,补播量1（垂穗披碱草播量为26.7 kg·hm-2,老芒麦播量为37.5 kg·hm-2,紫花苜蓿甘农1号为0）和划破草皮组合的植被高度(11.7 cm)达到最大值。就各补播水平平均值而言,划破草皮植被高度、总盖度、地上生物量和功能群物种多样性总指数显著高于未划破草皮。综合考虑高度、总盖度、地上生物量和功能群物种多样性总指数,经关联度分析可知,补播量2（垂穗披碱草播量为37.5 kg·hm-2,老芒麦播量为52.5 kg·hm-2,紫花苜蓿甘农1号18.3 kg·hm-2）和划破草皮为最优组合。     

Accumulation of mycotoxins in forage of winter pasture during prolonged utilisation of sward

The concentration of mycotoxins in sward depending on time of pre-utilisation in summer and date of harvest in winter was analysed during the 2000-2002 vegetation seasons. Additionally, the yield of pasture sward was estimated. Higher concentrations of ochratoxin A--respectively: 0.55 and 050 ng/g DM--were found in the pasture sward harvested in December and January when compared to the sward collected in November (0.36 ng/g DM). The average concentration of zearalenone varied from 2.74 ng/g DM in December, to 6.00 ng/g DM in November and 9.77 ng/g DM in January. The highest concentration of ochratoxin A was 1.82 ng/g DM and zearalenone 47.89 ng/g DM. The highest number of samples in which ochratoxin A exceeded the level of 0.3 ng/g DM was noted in sward harvested in January (61.1%), while in the case of zearalenone, the number of samples containing this mycotoxin at a level exceeding 3.0 ng/g DM varied from 55.6% in December to 66.7% in November and January. It seems that the percentage of ochratoxin A positive samples and the toxin concentration level in the sward of winter pastures increased during the time of sward regrowth.     

刘家峡库区生态承载力研究

刘家峡库区自然条件严酷,生态环境脆弱,水土流失严重,亟需加快治理步伐。本研究通过计算分析刘家峡库区、库区南部三坪沟流域、库区北部碾子沟流域的生态承载力状况,为库区水土保持生态环境建设提供理论支撑。研究以生态承载力理论与方法为指导,建立了生态弹性度、资源承载力、资源承压度3级层次的生态承载力综合评价指标体系。分析表明,刘家峡库区目前生态弹性度为不稳定状态,水资源承载指数为低承载,土地承载饱和度为严重超载,库区处于不可持续的发展状态。应以提高库区生态承载力为目标,开展库区水土流失综合治理。     

草地植被恢复措施对高寒草甸有毒植物的影响

通过对高寒草甸天然草地实施划破、补播、施肥及综合处理,探讨了不同草地植被恢复措施对高寒草甸有毒植物物种组成、多样性及生物量的影响。结果表明,不同处理草地中,有毒植物的组成及比例差异显著(P<0.05)。与对照相比,补播、划破和施肥均不同程度地降低了群落中有毒植物的物种数和Shannon Wiener指数(P<0.05),不同处理草地有毒植物物种数和Shannon Wiener指数排序分别为补播<施肥=综合处理<划破<对照,补播<划破<施肥<对照<综合处理。补播、施肥和综合处理均可有效降低群落中有毒植物的地上生物量(P<0.05),而草地划破在一定程度上增加了有毒植物的地上生物量(P>0.05),不同处理草地有毒植物地上生物量排序为补播<综合处理<施肥<对照<划破。补播形成的垂穗披碱草(Elymus nutans)单一优势群落使有毒植物物种数、物种多样性及地上生物量均下降到最低值,对于毒杂草型退化草地的改良,草地补播是可供参考的有效恢复措施之一。     

划破草皮对不同地形高寒草甸草原植被特征的影响

在青藏高原东缘东祁连山高寒草甸草原开展平地和坡地划破草皮试验,研究了划破草皮对植物群落特征及地下生物量的影响。结果表明:划破处理对平地土壤含水量的改良效果显著优于坡地。划破处理增加了平地禾本科优势度而降低了坡地莎草科优势度。增加了平地禾本科高度,降低了坡地莎草科高度。平地和坡地划破区杂类草密度显著低于对照区,平地禾本科密度显著增加。与对照区相比,两种地形划破草皮都能减少杂类草生物量,平地划破区禾本科生物量显著增加,地下生物量/地上生物量显著大于对照区。说明划破草皮在平地是一种有效的改良措施,而在坡地改良效果不显著,建议在使用划破草皮技术改良高寒草甸草原时,应因地制宜,充分考虑制约条件。