1、The New Rangeland Ecology: A Bud that Blossomed to a Flower新草场生态学：学科发芽的过程,Lynn HuntsingerUniversity of California, Berkeley,Main Points要点,Understanding of the dynamics of rangeland ecosystems have changed.对草场生态的多变性有新的认识The models used in the United States have been shaped by social and economic cond
2、itions unique to U.S. history.美国的草场管理模型纳入社会和经济的变量Understanding rangeland ecological dynamics, and using the right model, is essential for good policy.了解草场生态系统的多变性以及使用适合的模型决定着政策的成败,Outline汇报内容,Definitions: what is rangeland ecology and why models?定义：什么是草场生态学？为什么模型？Linear Succession Model based on suc
3、cession theory基于演替的线性演替模式New Rangeland Ecology: States and Transitions Model based on non-equilibrium theory新草场生态学：基于非平衡理论的状态-过渡模型Influences on development policy对发展政策产生的影响,Rangelands草场,Rangelands: lands that are not cultivated, not artificially irrigated, not timber forests. They include grasslands
4、, deserts, alpine areas, montane meadows, tundra, woodlands, savanna, shrublands.草场：没有种植，灌溉和用材木的土地，包括草地，沙地，高寒草原，山地草甸，冻原，林地，热带草原，灌丛带About 2/3 of the land surface of the earth,Central question: What is the impact of management on rangelands?核心问题：管理对草场带来的影响,Grazing：放牧No Grazing：没有放牧Fire：燃烧Weather：天气See
5、ding, plowing, etc.：种、耕,We usually manage at the “plant community” scale平常在植物群落的尺度上进行管理,The “steppe” vegetation type：高寒草原的植被类型A needle grass (Stipa spp.) grassland ：针茅属为主的草地,Ecosystem Models:生态系统模型,Show some of the many interactions among organisms and environment阐述生物与环境之间的一些关系Help us organize infor
6、mation整理信息Can help predict management outcomes预测管理结果Should help to explain the system说明系统Should help us understand how things work, which interactions are important了解不同变量之间的关系，提出那些关系相对重要,Why do scientists create models?科学家为什么建立模型？Why do managers want models? 管理者为什么需要模型？,-organize information and que
7、stions：整理信息和问题,-understand how a system works：认识系统的运作,-predict outcomes of management：预测管理的结果,-test effects of variables：试验变量的影响,What causes vegetation change?那些因素导致植被的变化？,Models, based on theories of what drives vegetation change, are created to “explain” what happens on rangelands, and how rangela
8、nds will respond to management.基于导致植被变化的理论，建立模型来解读草场发生了什么？草场对管理的反馈？What explanatory model(s) fits rangelands best?那些解释模型最适合草场？,Models for Vegetation Change at Management and Plant Community Scales在植物群落与管理尺度上的植被动态模型,Succession Model演替模型,Succession is the change in an ecosystem or community over time.
9、 The time scale is years.演替指群落或生态系统在时间尺度上的辩护，其时间尺度指年份The classical model describes plant succession as:古典模型模型解读植被演替： 1) linear 线性2) reversible 可逆的 3) predictable 能预测的4) biotically controlled 靠生物技术可控制的 5) with a stable end point. 稳定的状态,Clements: Space for Time Study in the Tallgrass Prairie克莱门茨：高杆草原在
10、空间上的时间分析,10 grasslands never plowed10个从未种耕的草地,10 grasslands plowed20 years ago10个种耕20年的草场地,10 grasslands plowed last year10个去年种耕的草地,10 grasslands Plowed 50 years ago10个种耕50年以前的草地,A way of studying vegetation change over time在时间尺度上研究植被变化的方法,(Clements, 1916),Assemble into “successional sere”归结到生态演替系列,
11、Disturbance : reverses the progression to the endpoint, starts the process over as “secondary succession” 干扰：逆转演替发展到终点，重新开始次级演替,Never plowed/plowed 50 years ago,Plowed 10 years ago,Freshly Plowed,Plowed 20 years ago,Linear, deterministic (Clementian) succession for a specific climate具体气候下的线性的、确定性的演替
12、,Succession (plant interactions, competition),Disturbance (fire, grazing, plowing),Stable, climax, endpoint for climate,Develops like an organism to maturity.,Linear succession model线性演替模型,Seral stage1,Seral stage2,Seral stage3,“Equilibrium”4Stable End Point,“CLIMAX”,“MID-SERAL”,“PIONEER”,Tall grass
13、 Prairie(50 yearsago or never plowed),Taller, perennial grasses(20 yearsago),Early grasses (10 years ago),Pioneer species(just plowed),Controversial among scientists, with other ideas promoted, but no big change until the 90s.科学家之间的争议，直到90年代没有变化,But, a perfect fit to management needs at the time.但，很
14、好地适应与当时的管理需求,Fit the social and ecological conditions of the United States：适应与当时的美国社会和生态的条件Most rangelands owned and managed by the government, needed a “scientific” way to make decisions 大部分草场都由政府管理拥有和管理，需要“科学性”的决策First government agency to start managing rangelands established in 1911 Clements pub
15、lished in 1916. 第一次草场管理机构建立与1911，而克莱门茨出版与1916年Use science as a reason for allocating resources among livestock producers 科学作为依据来把资源分配给各畜牧业生产者,Adopted for Management管理者的采取,Increasing grazing pressure (disturbance),“CLIMAX”,“MID-SERAL”,“PIONEER”,Tall grass Prairie,Taller, perennial grasses,Early grass
16、es,Pioneer species(just plowed); annuals, weeds,Carrying capacity,# animals allowed,Used for “Range Condition”,“CLIMAX”,“MID-SERAL”,“PIONEER”,Increasing grazing pressure,Measure management outcomes by measuring how similar the species composition is to climax. 利用与测量管理的影响：测量物种的结构与顶级群落的相似性,“Degraded”,
17、“Pristine”,Excellent,Poor,Good,Fair,Condition,“Rangeland Condition”草场情况,Linear-succession based method of assessing rangeland condition was used widely in the west until recently.基于线性演替模型的方法在西方草场状况研究中常用Climax = “excellent condition” 顶级群落：最好的的状态Early successional stage = “poor condition”初期延期阶段：不好的状态,
18、Management goal: Find the right level of grazing to maintain “good” or better condition based on succession theory管理目标：基于演替理论，需要合适的放牧程度来保持较好的草场状态,The closer to climax, the better the “condition”离顶级群落越接近，状态越好Condition measured by species composition: “climax” species vs. “pioneer” species 状态评估采取物种结构：
19、顶级物种与初期物种的比较Establish and regulate fixed “carrying capacity”: number of animals/mu for the year. 建立与规划承载量：每亩草场能养的牲畜数量,For government managers对于政府的决策者,A way to create rules for herders, allocate use：建立规则和资源分配的方法A way to measure affects of management测量管理影响的方法Predicted management outcomes 预测管理结构Only ma
20、nagers had the “scientific capacity” to measure condition, set stocking rates：只有管理者具有“科学依据”来衡量状况，并制定承载率Helped consolidate government authority 帮助统一政府权利,20th Century: Four assumptions for rangeland development in U.S.20世纪：管理美国草场发展提出四个设想,Professional experts should be in charge, need “scientific” mana
21、gement-locals know nothing, they are backward 专家领导管理，需要“科学性”的管理而当地人无知、落后Technology is the way to solve problems 技术是解决问题的方法Goal for rangelands is to maximize livestock production at a sustainable carrying capacity草场管理的目标是基于可持续承载率，畜牧业生产加大化Comprehensive rational planning is key-locals are self-interest
22、ed and short-sighted 综合理性的规划是关键当地人目光短浅、自利,Outcome: Stronger government control,Management Method管理方法,Establish a fixed number of animals for a fixed area: carrying capacity 固定区域里限制牲畜数量：承载率Divide rangelands into areas used by individual households and regulate carrying capacity to sustain “rangeland
23、condition” 草场分配到各户来管理承载率，实现可持续的草场状态,Thanks to M. Fernndez-Gimnez for figure,Change in land tenure from shared land to individual land,Land shared,Land used separately,Clementian succession: does the model fit arid rangelands?克莱门茨演替：该模型是否适合用在干旱草场?？,Clements research in Tall Grass Prairie 高杆草原Predicta
24、ble, high rainfallGrasses compete to drive succession,Clementian succession: does the model fit arid rangelands?克莱门茨演替：该模型是否适合用在干旱草场？,“Linear Deterministic Succession”,Seral stage1,Seral stage2,Seral stage3,“Stable Equilibrium”4,“CLIMAX”,“MID-SERAL”,“PIONEER”,Excellent,Poor,Good,Increasing grazing p
25、ressure, disturbance,Fair,Range Condition,A way to predict results of disturbance/grazing.,“Degraded”,“Pristine”,Problem I: Not Linear问题：非线性,Seral stage1,Seral stage2,Seral stage3,“Stable Equilibrium”4,“CLIMAX”,“MID-SERAL”,“PIONEER”,Reality: There are multiple pathways, and multiple stable states. 现
26、实：多重渠道和多重稳定状态,“Range Condition”草场状态,Seral stage1,Seral stage2,Seral stage3,“Stable Equilibrium”4,“CLIMAX”,“MID-SERAL”,“PIONEER”,Excellent,Poor,Good,Increasing grazing pressure, disturbance,Fair,Range Condition,A way to measure management outcomes.测量管理结构的方法,“Degraded”,“Pristine”,=,Problem II: “condit
27、ion” is a value judgment,Excellent,Poor,Good,Fair,Reality: Each “state” or potential vegetation community, has value. “Lower” stages may be more productive, or more biodiverse, than later stages. Earlier stages may be more useful to herders, and in some cases, more “natural”.,The concept of degradat
28、ion is highly subjective退化的观点的是主观性强,Change in species? : are there “good” and “bad” species? 物种的变化？:是否有“好的”和“不好”的物种Whether a species is good or bad depends on your goals and point of view 物种的好坏取决于个人的目标和观点Linear succession models create “false normative value” 线性演替模型提出“错的规范价值” Change in bare areas? 裸
29、地变化Weather , drought, rodents, or grazing? 天气、干旱、啮齿类动物、还是放牧Loss of soil? 土壤的变化Influences long term productivity 影响长期的生产“Natural” or caused by management? “自然”的还是管理导致的Some arid lands have flood/drought cycles 有些干旱去有干旱、洪水的循环,Major driver of change is grazing放牧是变化的主导,Seral stage1,Seral stage2,Seral sta
30、ge3,“Stable Equilibrium”4,“CLIMAX”,“MID-SERAL”,“PIONEER”,Excellent,Poor,Good,Increasing grazing pressure,Fair,Reduce grazing to “improve” vegetation state.减少放牧来提高植被状态,“Degraded”,“Pristine”,Problem III: Major driver of change is abiotic factors非生物因素是变化的主导,Increasing grazing pressure,Reducing grazing
31、may not lead to a return to climax state, and heavy grazing may not lead to “degradation”. Climate/weather overwhelms impacts of grazing on arid rangelands.减少放牧并非能重回顶级状态，而大量的放牧压力不会导致“退化”。在干旱草场，气候、天气的影响比放牧重要,“Degraded”,“Pristine”,Ecological Site: Soils, slope, aspect, etc.,Plant Community,Ecological
32、Site: Soils, slope, aspect, etc.,Plant Community,No stabilizing feedbacks, uncoupled system,Problems with the model: it is not a good fit 模型的问题：不匹配,Change can be set off on different trajectories by disturbance, weather conditions, seed availability, etc. and this change may not be reversible, and m
33、ay lead to an alternate stable state of vegetation. 干扰、天气、种子的利用性等多种因素使变化进入不同的轨道Abiotic factors may be major drivers of system change.非生物因素也许是系统变化的主因Includes a value judgment: the end state (climax) is “good”, everything else is not so good.包含价值评估：顶级的终点号，而其它都不好？Non-climax states have their own set of
34、 values for biodiversity, aesthetics, carbon, etc. 非顶级状态都有自己的生物多样性、美观、碳汇等价值,Building a better model.建立更好的的模型,Non-equilibrium theory seeks to explain: 非平衡理论解读,Biotic interactions may not be the major driver 生物的相互作用并非主要的驱动因素Multiple possible stable states, not just one climax (Clements, etc) 有多重的状态，并非
35、只有一个顶级状态Disturbance, such as grazing and fire, may have a positive role in ecosystems 干扰、包括放牧、燃烧等对生态系统具有积极作用Management outcomes are not very predictable 管理结果很难预测,Non-Equilibrium Dynamics 非平衡动态,There are many possible “stable” stages of vegetation for a given ecological site. 在摸个生态系统中有多个植被稳定状态 The pr
36、imary driver of vegetation change is abiotic factors.植被变化主因是非生物因素：Not manageable 难以管理Not responsive to grazing 与放牧并非相应的Unpredictable (e.g. rainfall) 难以预测Management must be for uncertainty. A fixed “carrying capacity” cannot be set. 管理必须基于不确定性：很难建立固定的承载率,Management Model: States and Transitions 管理模型：
37、状态-过渡模型,Identify an “Ecological Site”: environmental conditions define a sitesoils, climate, site history. 识别一个生态系统点：环境特征定义一个点土壤、气候、该点的历史Identify possible vegetation states 识别可能的植被状态Identify the transitions among states 识别不同状态之间的过渡What causes a particular transition? What led to a particular state?
38、那些因素导致过渡？什么导致特定的状态,States and transition models must be for specific “Ecological Sites” based on abiotic factors 状态-过渡模型必须在特定生态系统点，基于非生物的因素,Soils 土壤Climate 气候Aspect, topography 方向、地貌,State and Transition Models状态-过渡模型,“States”: relatively stable ecosystem within temporal scale of interest “状态”：在指定的时
39、间尺度上的相对稳定的系统2. “Transitions”: changes among states within spatial and temporal scale of interest “过渡”：在指定的时空尺度，不同状态的变化,S1,S2,T1,T2,Westoby et al. 1989,1 Ecological Site, 3 States,State 1,State 2,S1,S2,Why are states stable? 为什么状态是稳定的？ Ball and Cup Diagram for States and Transitions,Transitions,Thres
40、hold (need to cross it for a state change),T1: Long droughtT2: Human action,T1T2,States and Transition Models状态-过渡模型,Based on data, not assumptions 基于数据而不是设想Can incorporate both equilibrium and non-equilibrium dynamics 可以包含平衡与非平衡动态Can be changed as we learn more 随着学习可以变动States and transitions are si
41、te specific 状态-过渡是基于个体案例地,Vetter 2005: The debate between Equilibrium vs Non-equilibrium平衡与非平衡之间的争议,Most arid and semi-arid rangeland systems have both equilibrium and non-equilibrium dynamics depending on scale and site. 基于不同的尺度和案例地，干旱半干旱草场系统有平衡与非平衡两者的动态Coefficient of variation in rainfall greater
42、than approximately 30% = mostly non-equilibrium, arid lands 降雨量的差异系数大于30%= 大部分是非平衡、干旱区,Coefficient of variation in precipitation降水量的差异系数,(von Wehrden et al. 2012),Implications for Development Policy发展政策的含义,OLD: Four principles of rangeland development 草场管理的四个原则,Professional experts should be in char
43、ge, need “scientific” management-locals know nothing, they are backward 专家领导管理，需要“科学性”的管理而当地人无知、落后Technology is the way to solve problems 技术是解决问题的方法Goal for rangelands is to maximize livestock production at a sustainable carrying capacity草场管理的目标是基于可持续承载率，畜牧业生产加大化Comprehensive rational planning is ke
44、y-locals are self-interested and short-sighted 综合理性的规划是关键当地人目光短浅、自利,Four principles for non-equilibrium systems 非平衡系统的四个原则,Local knowledge is site specific and important: culture incorporates long term learning about adapting to unpredictable conditions 本土知识是区域特性的和重要的：文化包含适应不确定性的长期的经验Institutions, g
45、overnance may be most important in solving problems 制度、治理也许是解决问题的关键Multiple goals for rangelands 草场的多重目标Collaborative, adaptive management to maximize flexibility, sources of knowledge to cope with unpredictability 合作性、适应性的管理加大弹性和知识的来源应付不确定性,OLD: Management Method管理方法,Establish a fixed number of ani
46、mals for a fixed area: carrying capacity 固定区域里制定牲畜数量：承载率Divide rangelands into areas used by individual household and regulate carrying capacity to sustain “rangeland condition”草场分配到各户来管理承载率，实现可持续的草场状态,Management Method管理方法,Mobility (herding) across large landscapes allows herds to escape unpredicta
47、ble drought, find new pastures, we must not fragment rangelands 在更大景观区域上的牲畜移动使牧民更好地躲避难以预测的干旱，寻找新的草场，并不能破碎草场Social norms of reciprocity and sharing facilitate mobility and lower the costs and risks of herding 社会的互惠关系和分享促进移动和将定放牧的风险和成本Technological applications limited by lack of water, poor soils: we
48、 must adapt to the ecosystem, rather than changing it.贫瘠土壤和水源短期限制技术的实用性：必须适应生态，而并非改变生态,Whites ride,Thanks to M. Fernndez-Gimnez for figure,Non-equilibrium Strategy : Restore connections after privatization of land,More shared knowledge and governance,Conclusions: The ecological model used结论：应用的生态模型,Reflects the social and ecological conditions of the times. 体现当时的社会和生态状态Has a huge impact on policy and management. 对政策和管理产生巨大的影响Has a huge impact on the lives of herders and ranchers on rangelands. 对牧民的生活和牧场主产生巨大的影响,
