Antelope adaptations to counteract overheating and water deficit in arid environments

Many arid areas have very severe climates with extremely high summer temperatures,strong solar radiation,and a lack of drinking water during the driest season.Therefore,antelopes living in arid areas are forced to solve two main problems:avoiding overheating and maintaining water balance.Generally,there are physiological,morphological,and behavioral mechanisms for antelope adaptations to arid environments.Among the mechanisms,behavioral adjustments have a minimal cost and are activated first,while physiological mechanisms are the most energetically costly and involve adaptations to high temperatures when other mechanisms are insufficient.In previous publications,some examples of the antelope behavioral adaptations have been described only rarely,while in this review,we try to clarify all available information on the adaptations of antelopes living in arid areas to their native environments,paying particular attention to behavioral adjustments.Behavioral mechanisms,especially daily activity,diet and microclimate selection,and migrations,are so important and commonly used by antelopes in natural conditions,in which physiological mechanisms are usually not involved.Antelopes adjust their behaviors according to environmental changes so successfully that purely physiological mechanisms are discovered under laboratory conditions;for example,adaptive heterothermia or selective brain cooling phenomenon is difficult to observe in their natural habitats.This review provides a better understanding of the main behavioral mechanisms of antelope adaptations to arid environments and allows for the identification of the key factors for successful conservation of antelopes in their natural habitats.

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by humans.To understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were investigated.These rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global average.The δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,respectively.The end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate gradients.Multiple isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid environment.Based on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely exposed.While the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier environment.Besides,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

Landsat satellite programme potential for soil erosion assessment and monitoring in arid environments:A review of applications and challenges

This review article presents a comprehensive overview of the current status of the Landsat program and its applications in soil erosion modelling and assessment within arid environments.Literature for the period between 1972 and 2022 was retrieved using directed search strategies and keywords.A total of 170 journal articles were gathered and analyzed.The literature analysis reveals that 27(16%)of the publications fall within the period from 2007 to 2011,marking the highest occurrence within a five-year interval.The scrutinized literature was classified into ten distinct periods,or“pentades,”to accommodate the evolving applications of the Landsat program in response to advancements in remotely sensed data quality.This review article underscores the substantial contribution of Landsat data to the monitoring and assessment of soil erosion attributed to the action of water.Numerous studies have been conducted to model soil erosion using the Revised Universal Soil Loss Equation(RUSLE)model,facilitated by Geographic Information Systems(GIS)and remote sensing technologies.Nonetheless,the integration of Landsat data does present some challenges.Notably,the limitations of coarse resolution and data loss,particularly the scan line issues affecting Landsat 7,have hindered the full potential of the affected satellite datasets.As a solution,a multi-source approach that amalgamates diverse datasets is advocated to bridge data gaps and address disparities in spatial and temporal resolutions.To conclude,the Landsat mission has indisputably emerged as an indispensable instrument for facilitating the assessment and monitoring of soil erosion in resource-constrained communities.To advance this field,there is need to bolster storage infrastructure to manage large datasets,ensuring continuity for these sensor outputs,presenting a promising path for future research.

Ecological-hydrological processes in arid environment： Past, present and future

Ecohydrology, aiming to study the interactions between terrestrial ecological systems and hydrological cycles as well as their impacts on water management, has been an emerging interdisciplinary research field since the 20th century. It hosts both natural and human regulated processes that are potentially coupled in complex ways. Understanding the ecological-hydrological processes, the fundamental mechanisms and the connections be- tween them is critical since these processes are not isolated but integrated to impact ba- sin-scale hydrological and biogeochemical functioning of a larger river system, especially in arid environment where water resources are considered to be the source of life. Thus, re- search on ecological-hydrological processes in arid environment is not only a scientific focus area but also important to sustainable development. Research projects and initiatives involved in observation, measurement, modeling and data assimilation have been well-developed for those purposes over the past 20 years. This review summarizes the historical development of ecohydrology science in China and the state-of-the-art tools available in the research framework. Five grand scientific challenges are listed as prospects and exciting opportunities for the scientific community. To advance the current ecological-hydrological processes research, scientists from multidisciplinary backgrounds （such as geography, geology, geomorphology, hydrology, geochemistry and ecology）, need to unite to tackle the many open problems in new dimensions.

Analyses of environmental impacts of underground coal mining in an arid region using remote sensing and GIS

The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM＋ images with no cloud cover from July/August in different years （1990, 1995, 2000 and 2005） were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990＇s （70.61% in 1990, 71.43% in 1995）, to 43.64% in 2000 and 34.93% in 2005, respectively.

Influence of the Tibetan Plateau uplift on the Asian monsoon-arid environment evolution

As one of the most important geological events in Cenozoic era,the uplift of the Tibetan Plateau(TP)has had profound influences on the Asian and global climate and environment evolution.During the past four decades,many scholars from China and abroad have studied climatic and environmental effects of the TP uplift by using a variety of geological records and paleoclimate numerical simulations.The existing research results enrich our understanding of the mechanisms of Asian monsoon changes and interior aridification,but so far there are still a lot of issues that need to be thought deeply and investigated further.This paper attempts to review the research on the influence of the TP uplift on the Asian monsoon-arid environment,summarize three types of numerical simulations including bulk-plateau uplift,phased uplift and sub-regional uplift,and especially to analyze regional differences in responses of climate and environment to different forms of tectonic uplifts.From previous modeling results,the land-sea distribution and the Himalayan uplift may have a large effect in the establishment and development of the South Asian monsoon.However,the formation and evolution of the monsoon in northern East Asia,the intensified dryness north of the TP and enhanced Asian dust cycle may be more closely related to the uplift of the main body,especially the northern part of the TP.In this review,we also discuss relative roles of the TP uplift and other impact factors,origins of the South Asian monsoon and East Asian monsoon,feedback effects and nonlinear responses of climatic and environmental changes to the plateau uplift.Finally,we make comparisons between numerical simulations and geological records,discuss their uncertainties,and highlight some problems worthy of further studying.

ENVIRONMENTAL CHANGES IN NORTHWEST ARID CHINA DURINGRECENT 40 YEARS

The oases environment of arid lands in Northwest Chinahas been improved during recent 40 years, but the generalenvironments out of the oases have been deteriorating. This aniclediscusses the cause and effect of the environmental changes withthe aid of rich data and puts forward countermeasures fOr eco-enviromnental protection and improvement.

COLD AND ARID REGIONS ENVIRONMENTAL AND ENGINEERING RESEARCH INSTITUTE

The Cold and Arid Regions Environmental andEngineering Research Institute(CAREERI) wascreated in June 1999 as a result of the current PilotRroject of the Knowledge Innovation Program of theChinse Academy of Sciences (CAS). Formed onthe basis of three former CAS institutes,namely, theLanzhou Institute of Glaciology and Geocryology,the Lanzhou Institute of Desert Studies, and

砾石覆盖下的农田土壤环境效应:研究进展与展望

砾石覆盖是旱区特有的一种保护性耕作模式。长期的农业生产实践已经证明,地表覆砂能够很好地适应旱区严酷、恶劣的自然环境,并为当地农业发展和效益提升带来极大助力。然而,砾石覆盖农田退化所带来的一系列负面效应愈加凸显,成为当地农业发展的障碍因子。文章以砾石覆盖的土壤环境效应为脉络,归纳总结了砾石覆盖对土壤水热环境、土壤盐分、土壤有机质、土壤微生物和酶活性,以及水土保持等方面的影响效应和相关机制。同时,进一步指明旱区砂田当前所面临的问题与挑战,并提出该领域未来可持续深化和拓展的方向,主要包括:(1)砾石覆盖农田退化过程中土壤环境的综合演变机制;(2)“砾石-土壤-作物”系统间的协同作用机制;(3)应对砂田退化的农业修复模式及可持续发展路径;(4)砾石覆盖对局部区域气候的影响机制。

卡山保护区核心区璃眼蜱空间格局及成因

璃眼蜱是一类能够传播多种病原体的吸血媒介节肢动物。近年来璃眼蜱在新疆卡拉麦里山有蹄类保护区(简称“卡山保护区”)的泛化,对当地野生动物甚至保护区管护人员构成的威胁日渐突出。于2021、2022年在该保护区核心区设置25km^(2)样地,探究了璃眼蜱的空间分布及其影响因素,重点围绕璃眼蜱与普氏野马及啮齿类动物之间的空间关系展开。通过半方差变异函数分析璃眼蜱空间分布相关性;以双变量空间自相关方法评估璃眼蜱与宿主动物的空间聚集程度;采用结构方程模型拟合璃眼蜱数量与环境因素的关系。结果表明:1)璃眼蜱的块金基台比值大于0.75,显示璃眼蜱具有较低的空间相关性,表明其分布更易受到宿主及所处环境的影响;2)璃眼蜱与宿主的双变量梯度LISA聚集图表明,璃眼蜱与普氏野马之间的空间聚集关系强于璃眼蜱与啮齿类之间的空间聚集关系。3)多元混合结构方程模型的拟合效果较好(R^(2)=0.70),模型发现气候、植被、宿主三种因子均能影响璃眼蜱数量。综上,本研究发现影响卡山保护区核心区的璃眼蜱分布的最主要因素是宿主,其中普氏野马与璃眼蜱的空间聚集关系强于啮齿类动物。璃眼蜱随大型宿主的扩张性分布,对同域,特别是核心区其他野生动物构成了直接威胁。野生动物的重引入可能会对生态链中其他物种产生间接影响。随着普氏野马的重引入,该地区的寄生虫分布发生了变化,可能是因为寄生虫适应了新的环境条件,且这种适应性又依赖于普氏野马的分布。这种现象表明,生态系统中的各个组成部分都会相互关联,生态链的变化可能会导致其他生物适应性发生改变。该问题显示开展濒危野生动物重引入监测工作的重要性,研究结果拓展了野生动物蜱传疾病控制和管理思路。

The climatic and hydrological changes and environmental responses recorded in lake sediments of Xinjiang,China

Based on the analyses of environmental proxy data in lake sediments and instrumental records of Xinjiang in northwest China, the Holocene climate and hydrological variability and its environmental responses were studied in different time scales and regions. The results showed that the Holocene climate variability had obvious differences between the north and south of Xinjiang. In northern Xinjiang, the Holocene climate was dry in the early period, humid in the middle period, and then changed to dry in the late period. However, the climate transition times were not consistent in different regions. In southern Xin- jiang, although there were many different types of climate change patterns inferred from different catch- ments, the warm and wet climate was recorded in most lake sediments in the middle Holocene. According to comparisons of some millennium scale records in lake sediments, the climate was warm and dry in the past 100 years. It can be concluded the climate showed a trend of aridity in Holocene. Especially in recent 50 years, the lake area has been shrinking rapidly because of the population growth and social economic development, which brings some environmental problems. Lake level and area changes were sensitively affected by the climate variation in geological history of Xinjiang and the lake level will continue to shrink because of the drought climate and strengthened human activities.

Root characteristics of Alhagi sparsifolia seedlings in response to water supplement in an arid region,northwestern China

The effect of variation in water supply on woody seedling growth in arid environments remain poorly known.The subshrub Alhagi sparsifolia Shap.（Leguminosae）,distributed in the southern fringe of the Taklimakan Desert,Xinjiang,northwestern China,has evolved deep roots and is exclusively dependent on groundwater,and performs a crucial role for the local ecological safety.In the Cele oasis,we studied the responses of A.sparsifolia seedling roots to water supplement at 10 and 14 weeks under three irrigation treatments （none water supply of 0 m3/m2 （NW）,middle water supply of 0.1 m3/m2 （MW）,and high water supply of 0.2 m3/m2 （HW））.The results showed that the variations of soil water content （SWC） significantly influenced the root growth of A.sparsifolia seedlings.The leaf area,basal diameter and crown diameter were significantly higher in the HW treatment than in the other treatments.The biomass,root surface area （RSA）,root depth and relative growth rate （RGR） of A.sparsifolia roots were all significantly higher in the NW treatment than in the HW and MW treatments at 10 weeks.However,these root parameters were significantly lower in the NW treatment than in the other treatments at 14 weeks.When SWC continued to decline as the experiment went on （until less than 8％ gravimetric SWC）,the seedlings still showed drought tolerance through morphological and physiological responses,but root growth suffered serious water stress compared to better water supply treatments.According to our study,keeping a minimum gravimetric SWC of 8％ might be important for the growth and establishment of A.sparsifolia during the early growth stage.These results will not only enrich our knowledge of the responses of woody seedlings to various water availabilities,but also provide a new insight to successfully establish and manage A.sparsifolia in arid environments,further supporting the sustainable development of oases.

半干旱草原露天矿区生态累积效应:评估模型与应用

为揭示半干旱草原露天矿区生态环境质量状况,分离矿区人类活动生态累积效应并识别其演变态势,在厘清矿区生态累积效应概念的基础上,构建适用于半干旱草原的露天矿区生态环境质量评估指数(Surface Mining Areas Eco-environmental Evaluation Index,SMAEEI)以及矿区生态累积效应定量评估模型。选取内蒙古胜利矿区为研究区,量化分析1986—2020年区域生态环境质量和生态累积效应的时空分布规律,以及主要人类活动的生态累积效应差异。结果表明:①SMAEEI适用于半干旱草原露天矿区,能客观呈现各地类生态环境质量高低顺序。35 a间研究区生态环境质量呈极显著下降趋势,且其空间差异显著减弱。露天矿场、城镇扩张区、锡林河湿地及北侧草地生态环境质量出现极显著、显著的退化趋势。②半干旱草原露天矿区生态累积效应定量评估模型能剔除气候因素对生态系统的耦合影响,分离并量化人类活动对矿区生态系统的累积效应,揭示累积的方向、程度和空间范围。35 a间研究区生态服务价值累积量(Change of Ecosystem Service Value Cumulant,COESVC)共减少1186157.03万元,出现负向生态累积效应,生态系统服务功能下降。高度、中度负向累积区集中在湿地和草地退化区、城镇区、露天矿场。③露天开采、城镇建设造成的单位面积负向生态累积效应最明显,前者在单位时间内带来的负向累积变化最剧烈,后者负向累积效应的局部影响程度和偏离度最大;放牧活动引起的负向生态累积效应影响范围最广、总量最大,但局部影响程度最小,生态系统服务功能较其余人类活动更稳定。研究成果可将矿区人类活动引起的生态环境实物量变动转化为价值量描述,为采用货币形式测算矿区生产生活行为的环境损害成本提供可行方法。

中中新世气候适宜期全球变暖背景下亚洲内陆干旱区古气候演化特征及驱动机制

中中新世气候适宜期是新生代全球降温趋势下一次强烈的全球升温事件,其气候状态被认为是未来全球变暖最可能达到的状态。亚洲内陆干旱区是全球典型的中纬度干旱区,其干旱化过程对人类生存环境影响最为深刻、最为直接。在全球变暖背景下,叠加人类活动的影响,干旱区变得更加脆弱,其扩张或变迁都会直接影响人类的生存和可持续发展。探讨亚洲内陆干旱区在中中新世全球气候变暖背景下的气候演化历史,对未来气候变暖模式下干旱区的气候变化预估提供重要参考。本文梳理了亚洲内陆干旱区典型盆地现有中中新世期间古气候演化研究结果,通过环境磁学参数、孢粉、同位素等多种气候代用指标的综合分析,发现在中中新世期间,多数地区呈现湿润化,但开始的时间有所差异,同时,少量地区呈现持续干旱化的现象。另一方面,对中中新世适宜期形成的主控因素依然存在较大争议,有的学者认为哥伦比亚玄武岩喷发是主要因素,有的学者认为构造活动是主要因素。要解决上述争议,需要获取更多具有精确年代控制的高分辨率记录,以确定中中新世升温事件的起始响应时间。通过正确解译气候代用指标,特别是对古气候变化响应最为直接和敏感的孢粉,以及环境磁学参数和地球化学比值等蕴含的古环境信息,厘清各种因素对气候变化造成的影响,揭示亚洲内陆干旱区中中新世气候适宜期气候演化的驱动机制。

Observations of Red-billed Spurfowl(Pternistis adspersus) in the arid Molopo Nature Reserve,North West Province,South Africa

Field work was conducted in the southern half of the Molopo Nature Reserve(MNR) near Vostershoop in the North West Province of South Africa to(1) describe the past and present distribution of Red-billed Spurfowl(Pternistis adspersus) in South Africa and(2) to describe the dispersion of Red-billed Spurfowl at waterholes in the MNR.The Red-billed Spurfowl did not colonize this area from Bo-tswana in the 1990s as reported in Hockey et al.(2005) and their distribution status and population sizes are not determined by long distance(30-100 km) and/or seasonal movements between the two countries.Red-billed Spurfowl are sparsely distributed and mainly occur in clusters near man-made waterholes.Waterholes provide water and food found in and around antelope droppings.The movement of the Red-billed Spurfowl between waterholes over short distances of 2-5 km was probably encouraged by the sinking of more boreholes since the 1980s(and the creation of 'veeposte'(game/livestock camps) around them).Low rainfall that results in limited insects is probably the single most important factor limiting populations of the Red-billed Spurfowl in South Africa.

Assessment of impact of water diversion projects on ecological water uses in arid region

In arid regions, large-scale water diversion from rivers leads to significant changes in river flow regimes, which may have large impacts on ecological water uses of river-dependent ecosystems, such as river, lake, wetland, and riparian ecosystems. To assess the integrated impact of water diversion on ecological water uses, we proposed a hierarchy evaluation model composed of four layers representing the evaluation goal, sub-areas of the influenced region, evaluation criteria, and water diversion schemes, respectively. The evaluation criteria for different types of ecological water uses were proposed, and the analytical hierarchy process was used for the integrated assessment. For a river ecosystem, the percentage of mean annual flow was used to define the grade of environmental flow. For a lake ecosystem, water recharge to the lake to compensate the lake water losses was used to assess the ecological water use of a lake. The flooding level of the wetland and the groundwater level in the riparian plain were used to assess the wetland and riparian ecological water uses, respectively. The proposed model was applied to a basin in northern Xinjiang in northwest China, where both water diversion and inter-basin water transfer projects were planned to be carried out. Based on assessment results for the whole study area and two sub-areas, an appropriate scheme was recommended from four planning schemes. With the recommended scheme, ecological water uses of the influenced ecosystems can be maintained at an acceptable level. Meanwhile, economical water requirements can be met to a great extent.

ISSUES CONCERNING THE MANAGEMENT AND THE DEVELOPMENT OF ARID AND SEMIARID LAND IN CHINA

The arid and semiarid land in China covers a vast area, about 3.5 million km^2(not coun-ting the Tibet Plateau),where natural resources are very aboundant. In this area, the totalsolar radiation is as high as 140--160 kilocalorie / cm^2. a. There are about 167 million ha ofvarious grasslands, accounting for nearly 60% of the national grassland area.

REGULATING THE INDUSTRIAL STRUCTURE IS AN PRINCIPAL APPROACH TO THE ENVIONMENT ADMINISTRATION IN ARID AND SEMI-ARID AREAS

1. The crux of the environment administration problem is theeconomic development As we Know that the evolution of environment is not only due to Nature itself, but al-so to human being particularly. In the course of history, the Loess Plateau in China, oncewoody and rich in plants has now become a serious soil-erosion area on which lies thou-

Grazing exclusion-induced shifts,the relative importance of environmental filtering,biotic interactions and dispersal limitation in shaping desert steppe communities,northern China

Grazing exclusion is one of the most efficient approaches to restore degraded grassland but may negatively affects the recovery of species diversity. Changes in plant species diversity should be a consequence of the ecological assembly process. Local community assembly is influenced by environmental filtering, biotic interactions, and dispersal. However, how these factors potentially contribute to changes to species diversity is poorly understood, especially in harsh environments. In this study, two management sites within a Stipa breviflora desert steppe community（typical natural steppe） were selected in northern China. In one of the two management sites, grazing has been excluded since 2010 and in the other with open grazing by sheep. In August 2016, three plots were established and 100 sampling units were created within each plot in a 5 m×5 m area at the two management sites. To assess the effects of grazing exclusion on S. breviflora steppe, we analyzed the vegetation biomass, species diversity,soil organic carbon, and soil particle size distribution using paired T-tests. In addition, variation partitioning was applied to determine the relative importance of environmental filtering and dispersal limitation. Null mode analysis was used to quantify the influence of biotic interactions in conjunction with Eco Sim niche overlap and co-occurrence values. Our results demonstrated that（1） species diversity significantly decreased and the main improvements in soil quality occurred in the topsoil 0–10 cm after the grazing exclusion;（2） environmental filtering was important for community assembly between grazed and fenced grassland and this appears particularly true for soil particle size distribution, which may be well correlated with soil hydrological processes; and（3） however, competitive exclusion may play a significant role within the exclusion. The multiple pathways of assembly may collectively determine negative effects on the restoration of species diversity. Therefore, designers should be aware of the risk of reducing grazing exclusion-induced species diversity and account for manipulating processes. This in turn will reduce dominant species and promote environmental heterogeneity to maximize species diversity in semi-arid regions.

Multiple Impact of Integrated Watershed Management in Low Rainfall Semi-Arid Region: A Case Study from Eastern Rajasthan, India

The agriculture in low rainfall areas of eastern Rajasthan, India is characterized by high risks from drought, degraded natural resources and pervasive poverty, food insecurity and malnutrition. In this region, water is the main limiting factor for upgrading rainfed agriculture. For such areas integrated watershed management is recognized as a potential approach for agriculture growth and rehabilitation of fragile and degraded lands. At Gokulpura-Goverdhanpura village in Bundi eastern Rajasthan, India an integrated watershed project was implemented using the holistic systems approach. This paper discusses the impacts of this watershed program on bio-physical, socio-economic, environmental and ecological parameters. Results indicate that due to watershed interventions the groundwater availability has substantially increased which brought changes in cropping patterns with high value crops. Significant increases in irrigated area, cropping intensity along with diversification of crops from traditional to commercial cash crops were recorded. The watershed program also significantly improved the socio-economic status of the watershed community. It has increased the income and reduced poverty of the people in the watershed. The watershed interventions generated good employment opportunities and significantly reduced the migration of both skilled and unskilled labor from the watershed village to urban areas. It has also improved the environmental quality and ecological status in the watershed. The watershed interventions increased the vegetative index or greenery, reduced runoff, soil loss, and land degradations and improved the bio-diversity in fragile ecosystems. Overall, the integrated watershed program at Gokulpura-Goverdhanpura provided resilience by ensuring continued and sustainable multiple outputs, besides soil and water conservation and other positive environmental effects.