Climate Change and Water: Impacts & Management Needs 气候变化与水资源: 影响与管理需求 Roger Calow Water Policy Programme, ODI 罗杰
Overview 概述 1.The big picture 概括 1.Irrigation – surface water systems 灌溉 — 地表水系统 3.Irrigation - groundwater economies 灌溉 — 地下水节约 4. Conclusions 总结
The most vulnerable? 最脆弱群体?
Drivers of change & management challenges 变化动因 & 管理挑战 Major drivers? 主要动因? …urbanisation, industrialisation, consumption...with climate change overlay A water ‘crisis’? 水危机? …who gets what (Q, Q, R) in a variable climate: farms vs cities, upstream vs downstream, environmental vs human Adaptation challenge? 适应挑战? …mediating between competing claims: range of different scales Agricultural futures? 农业未来?...agriculture will lose water. How? Impacts on poorer households?
Agriculture & irrigation 农业 & 灌溉 Two stories: Surface water irrigation (IDs) –Development - state sponsored, driven –Management - increasingly commercial Groundwater irrigation –More recent, increasingly farmer-led & opportunistic –Boreholes 1949 (0) – today (>5M)...concentrated in water scarce north –Controllability, affordability...impacts
Water withdrawals in Hebei by sector, 1990 – 2003 河北省分部门采水量 Source: Hebei provincial WRD Statistical Yearbooks
Yellow River flows 黄河水流量
Prov.QHSCGSNXIMSA HNSDHBTot Alloc Yellow River Allocation Plan ( billion m 3 ) Water allocation in the Yellow River Basin 黄河流域水资源配给 Permit 1 Hangjin ID: 0.41 bcm Permits 2&3 Hetao ID: 4.77 bcm Defined under the YRCC’s Water Allocation Plan (long term) and adjusted under Annual Regulation Plans (annual) Defining and protecting farmers’ rights?
Irrigation diversion 灌溉
Water allocation – basin to household 水资源分配 — 从流域到用户 Basin Allocation Agreement ProvinceQHSCGSNXIMSAASAHNSDHBTotal Alloc Hangjin Irrigation District 280GL ( abstraction) Hetao Irrigation District Abstraction permits Water User Associations Channel Losses Other users Group water entitlements Water certificates Household
Hangjin - channel lining 夯井 — 分渠灌溉
Channel lining and water transfer: winners…and losers? 分渠灌溉与水资源转移:赢家与输家? MuganBalahaiJianshe Gross permit before trading 410 mcm Return flow before trading 35 mcm Saving after trading 130 mcm Return flow after trading 35 mcm Gross diversion after trading 280 mcm Water Permit of 5860 mcm Water diverted before trading 375 mcm Water diverted after trading 245 mcm
Key messages – IDs & water transfers 关键点 —IDs 与水资源配给 1.Irrigation will lose market share 2.Supply will fluctuate...variability will increase 3.Deepening rights reform (basin to farmer) will grow in importance 4.Protecting the interests of poorer households as water is reallocated will depend on: –Informal claims (WUAs, contracting) –Sound science – basin efficiencies, consumptive rights –Willingness to recognise effects on ‘3 rd parties’ & environmental flows
‘Water & Agricultural Management in Hebei’ 河北省水资源与农业管理
Total water withdrawals in Bashang counties, 1995 – 2005 坝上县水资源抽取总量 Surface water Ground water Surface water Ground water Surface water Ground water Year Withdrawal (m 3 x 10 3 ) Zhangbei Guyuan Shangyi Kangbao Source: personal communication, Zhangjiakou City Water Affairs Bureau 2005.
Groundwater level changes recorded for three Bashang counties, 2003 – 2005 地下水水位变化记录 Source: Zhangjiakou City Water Affairs Bureau, 2006.
Predicted groundwater level declines in the Bashang 可预测地下水位下降情况 Source: WAMH Note: drawdown modelled over a 10 year period based on 2003 estimates of groundwater abstraction and recharge.
Irrigation development and control areas in the Bashang
Control areas - well drilling in the Bashang 控制区 — 井水抽取
Groundwater management challenge 地下水管理挑战 CountryAnnual groundwater use (km 3 ) No. of groundwater structures (million) Extraction/ structure (m 3 /year) % of population dependent on groundwater India ,000-10, Pakistan , China , Iran , Mexico , USA ,000<1-2 Source: Shah, 2004
WUAs & quotas In the long-term: 长期 Scale-up to reduce free- riding Tie quotas to variable shares of aquifer safe yield Progress: 进展 Shared allocations Conservation incentives Devolved management
A farm economy? 农业经济?
Shifting livelihoods 生活水平变化 Rural jobs – RNFE, migration Rural incomes – diverse, dispersed Dependence on CPRs - declining Drivers of change – small push, big pull Sources of vulnerability – income shocks Nature of community – boundaries blurring Rural development narrative – income, employment Vulnerable are locked in to the ‘old’ economy
Key messages – protecting high value aquifers & services 主要信息 — 保护高价值地下蓄水层 & 服务 Groundwater access – key role in poverty reduction But monitoring patchy, numbers uncertain, impacts of climate change unclear Protecting the interests of poorer households will depend on: –Extending access to GW irrigation –Prioritising domestic water –Protecting key reserves –A different approach to management…devolving tasks and functions…supported by sound science
Adaptation & development 适应与发展
Conclusions 结论 Adaptation as development 发展型适 应 Climate as one pressure… 气候压力 Agriculture as a water bank 农业 = 水资源银行 Rural households as winners & losers…who are the losers? 谁才是赢家与输家?
Thank you 谢谢 Beijing, February