无定河流域农田与草地生态承载力变化及其限制因素分析

随着自然资源有限性与人类需求无限性之间的矛盾日益加剧,如何实现生态环境与社会经济可持续发展、维护区域生态安全成为人类面临的重大挑战。本研究以无定河流域为研究区,基于食物营养供给与消耗、牧草供给与消耗估算了2000–2020年各县域农田与草地生态系统的承载力与承载状态指数,评估了流域生态承载状态及其变化,识别了关键生态承载限制类型,并基于水资源承载力进一步分析水资源供给的制约作用。结果表明,近20年无定河流域草地牧草供给与消耗均呈增长趋势;农田食物供给增长,而人均消耗略有下降;各县域草地与农田承载状态以转好为主。总体上流域生态承载状况明显转好,80%的县域综合生态承载指数减轻,而北部杭锦旗与东南部县域承载状态加重,牧草供给是其主要限制类型;鄂托克旗与鄂托克前旗水资源生态承载状态加重,水资源是北部县域农牧业生产主要限制性因素。未来发展中需重视生态保护与修护、合理安排种植业与畜牧业规模,减轻草地生态系统承载压力。

基于供给—消耗关系的蒙古高原草地承载力时空变化分析

在全球气候变化与人类活动加剧的双重影响下,蒙古高原草地放牧超载与草地退化问题不断凸显。如何从畜牧业生产对草地利用强度角度揭示草地生态系统的人地关系,对草地资源可持续利用对策研究至关重要。基于生态系统供给与消耗平衡关系,利用卫星遥感数据与畜牧业统计数据,分析蒙古高原草地生态系统的生态承载状态,研究不同政策背景和资源禀赋条件下草地生态系统承载压力的区域差异特征。研究结果表明:(1)内蒙古自治区和蒙古国两地不同的政策和习俗深刻影响了牧民对草地的利用方式,使得两地畜牧业生产结构产生显著差异,内蒙古自治区牲畜类型组成区域差异性大、总量相对平稳,而蒙古国牲畜数量增加显著、牲畜类型组成区域分布更为均匀。(2)内蒙古自治区和蒙古国草地消耗量均呈现出明显的上升趋势,蒙古高原草地资源消耗总量在2014年超出了供给量,其中内蒙古自治区草地资源消耗量在2005年超出了供给量,而近年来蒙古国的草地资源消耗量也逐渐逼近供给量。(3)2000-2016年间,蒙古高原草地承载压力不断增大,整体从盈余状态变为临界超载状态,持续严重超载地区主要出现在荒漠草原地区,并逐渐向典型草原及农牧交错区推进;蒙古国自2003年起富富有余状态区逐步减少且严重超载区逐步增多,内蒙古自治区则受生态保护政策的影响呈波动性变化。通过定量分析内蒙古自治区和蒙古国草地承载状况的时空差异性,所揭示出的不同社会经济背景下畜牧业生产结构与强度的变化规律可为草地资源管理提供科学依据。

Assessing the Ecological Carrying Capacity of Countries along the Belt and Road

The Belt and Road Initiative(B&R Initiative)is a crucial strategy to promote regional sustainable development in the new era.However,the realization of the B&R Initiative faces huge challenges because of the dual characteristics of a fragile eco-environment and strong dependence on ecological resources for economic development in the Belt and Road(B&R)countries.The ecological carrying capacity(ECC)is a crucial indicator for evaluating regional sustainable development.From the perspective of the relationship between the supply and consumption of ecological resources,this study uses net primary productivity data to measure the supply capacity of ecological resources,and it uses the agricultural production and trade data provided by the United Nations Food and Agriculture Organization to measure the level of ecological resource consumption.These supply and consumption data are then used to assess the ECC and ecological carrying status(ECS)of the B&R countries in 2017.The results show that:(1)The ECC of the B&R is 11.097 billion people;the ecosystem can also support 6.433 billion people,and the ECC is in a state of rich and surplus.(2)The ECS is polarized among the regions and countries along the B&R.Of the 65 countries,the ECC of 40 countries is in a rich and surplus state,mainly in Mid-East Europe and Southeast Asia,while the ECC of 19 countries is in severe overload,mainly in West Asia/Middle East.(3)Although the ecosystems still have ample carrying space in countries along the B&R,ecological protection is still facing enormous challenges during the implementation of the B&R Initiative combined with the internationally recognized ecological protection standards as well as the forecasts of the population and economic development.As the core content of building a new international trade network,the B&R Initiative will help to solve the spatial mismatch between the supply and consumption of ecological resources,which provides a new opportunity to coordinate the contradiction between the ecological protection and social demands of the B&R countries.

Research on Ecological Carrying Pressure in the Greater Dunhuang Region based on the Relationship between Supply and Consumption

The Greater Dunhuang Region has experienced ecological degradation in the past 100 years caused by human factors such as ecological immigration, expansion of arable land, and the construction of reservoirs. At present, through the restoration of various ecological projects, the progress of ecological deterioration has slowed down. Ensuring that the development and construction of the Greater Dunhuang Region Cultural Tourism Economic Circle does not threaten ecological security is the top priority of the regional sustainable development plan. Based on the balance between supply and consumption of the ecosystem, this study assesses the pressure of ecological consumption in the Greater Dunhuang Region, and analyzes the patterns and trends in the ecological carrying status. The results reveal three important aspects of the ecological carrying pressure in this Region.(1) After 2000,the ecological supply in the Greater Dunhuang Region experienced a fluctuating growth trend. In the entire ecosystem, the farmland ecosystem provides more than 55% of the ecological supply, and areas with relatively high supply capacity are concentrated in a small number of valleys.(2) The Greater Dunhuang Region is under greater production pressure and there is less pressure from living consumption. The production consumption intensity has exceeded the ecological supply since 2014. The production and consumption structure of the Greater Dunhuang Region is dominated by animal husbandry production and consumption, accounting for more than 65% of the total production and consumption.(3) The Greater Dunhuang Region has been in a state of rich and surplus from 2000 to 2017. However, Dunhuang City turned into a surplus state in 2017 due to the pressure of the fast-growing tourist population. The Greater Dunhuang Region urgently needs to alleviate the ecological pressure through the development of eco-friendly industries. It is necessary to develop an ecological protection resource utilization model that focuses on the development of ecological and cultural services in pastoral areas to ease the pressure on the ecosystem from animal husbandry production.